WO2009139503A1 - Electric power conversion device - Google Patents

Abstract

Provided is an electric power conversion device for supplying an AC oscillation current to an induction load.  The electric power conversion device has a simple circuit configuration requiring a small number of inverse-conductive semiconductor switches.  Moreover, the inverse-conductive semiconductor switches perform soft switching operation, which causes only a small conduction loss of the inverse-conductive semiconductor switches.  Furthermore, it is possible to change the frequency of the AC oscillation current supplied to the induction load.

Description

 Specification

 Technical field of power conversion equipment

 The present invention relates to a power conversion device that converts DC power to AC power, and to a power conversion device that uses a magnetic energy regenerative switch to change the frequency of the output AC power and reduce the conduction loss of semiconductor elements used for switching. Is related to the position. Background art

 Conventionally, various methods for converting DC power to AC power have been put into practical use. Miniaturization and high efficiency of equipment are desired, and there are also demands for fewer components and simple control. If the switching frequency is increased to reduce the size of parts such as an insulation transformer, the loss due to switching generally increases. In high-speed switching where the switching frequency exceeds 10 KHz, the loss caused by the voltage X current is much larger than the conduction loss of the semiconductor element in the on-off transient state of the semiconductor element used for switching. Yes.

 Although the advent of semiconductor elements that support high-speed switching is desired, on the other hand, as a circuit technology, either or both of the voltage and current applied to the semiconductor element when the semiconductor element used for switching is turned on / off is abbreviated. Zero-switching soft switching technology is an important solution.

On the other hand, a circuit technology called magnetic energy regenerative switch (hereinafter referred to as “MERS”) has been proposed and has already been established as a patent (see Patent Document 1). MERS does not have reverse blocking capability, that is, uses a reverse conduction type switching circuit / "semiconductor element. As a reverse conduction type switching circuit / semiconductor element, for example, a self-extinguishing element and a diode are used. A circuit consisting of a positive element side connected to the negative electrode side of a diode and a negative electrode side of a self-extinguishing element connected to the positive electrode side of a diode, or a semiconductor such as a power MOSFET with a built-in parasitic diode during manufacturing (Hereinafter, these reverse conduction type switching circuit Z semiconductor elements are simply referred to as “reverse conduction type semiconductor switches”).

 MERS consists of a negative-electrode side of the self-extinguishing element constituting the first reverse-conducting semiconductor switch (hereinafter simply referred to as “the negative-electrode side of the reverse-conducting semiconductor switch”) and a second reverse-conducting semiconductor switch. The first reverse-conducting semiconductor switch leg and the third alternating-current terminal are connected to the positive-electrode side of the self-extinguishing element (hereinafter simply referred to as the “positive-electrode side of the reverse-conducting semiconductor switch”). The second reverse-conducting semiconductor switch leg is connected to the first reverse-conducting semiconductor switch leg with the second AC terminal at the point where the negative-electrode side of the reverse-conducting semiconductor switch and the positive-electrode side of the fourth reverse-conducting semiconductor switch are connected. Connect the positive poles of the semiconductor switch and the third reverse conducting semiconductor switch to the positive terminal, and connect the negative poles of the second reverse conducting semiconductor switch and the fourth reverse conducting semiconductor switch to the negative pole. Full blister configured as a terminal A circuit, and a capacitor connected between the positive terminal and the negative terminal of the full bridge circuit.

 Connect the circuit to be controlled by M E R S between the first AC terminal and the second AC terminal of the full bridge circuit.

The first reverse-conducting semiconductor switch and the fourth reverse-conducting semiconductor switch are the first pair, the second reverse-conducting semiconductor switch and the third reverse-conducting semiconductor switch are the second pair, and the first The self-extinguishing element constituting the two reverse conducting semiconductor switches in the pair is in a conducting state (hereinafter simply referred to as “reverse conducting semiconductor”). When the switch is in the “on state”, the self-extinguishing element constituting the two reverse conducting semiconductor switches of the second pair is blocked (hereinafter simply referred to as “switch-on state”).

When the first pair is off, the reverse conduction semiconductor switch is turned on and off so that the second pair is on. By controlling the state, MERS allows the capacitor to absorb the “snubber energy” stored in the entire bridge circuit and the controlled circuit when the circuit current is cut off. It functions as a bidirectional current switch circuit that can be regenerated in the circuit. The direction of the current flowing in the control target circuit can be switched between forward and reverse depending on the purpose and range of the control.

 When a circuit in which an inductive load and an AC power source are connected in series as the control target circuit between the first AC terminal and the second AC terminal of MERS, the AC power supplied to the inductive load is controlled. can do. Resonance between the condenser and the inductance component of the inductive load causes the capacitor to absorb the “magnetic energy” stored in the inductance component of the inductive load (the capacitor is charged) and regenerate the inductive load (the capacitor is This is realized by discharging. This has been proposed as an AC power supply device using M E R S and has already been granted as a patent (see Patent Document 2).

In the AC power supply using MERS, the capacitance of the capacitor is the capacitance that resonates with the inductance of the inductive load, and the capacitance is selected according to the purpose and range of control. In particular, by selecting the capacitance of the capacitor so that the resonance frequency determined by the capacitance of the capacitor and the inductance of the inductive load is equal to or higher than the switching frequency of the reverse-conducting semiconductor switch, the reverse-conducting semiconductor When the switch is turned on, the self-extinguishing element constituting the reverse conducting semiconductor switch has substantially zero voltage and zero current. Further, when turned off, the self-extinguishing element constituting the reverse conducting semiconductor switch can perform a soft switching operation with substantially zero voltage.

 In the AC power supply using MERS, when the first pair of reverse conducting semiconductor switches is in the on state, the second pair is in the off state, and when the first pair is in the off state, The ON / OFF state of the reverse conducting semiconductor switch is controlled so that the pair 2 is turned on. The time ratio (duty ratio) between the on time and off time of the reverse conducting semiconductor switch is 0.5, that is, the on time and the off time are equal. When the reverse conduction type semiconductor switch ON / OFF state expressed on the time axis is the control signal, the phase of the control signal is synchronized with the voltage phase of the AC power supply, and the phase of the control signal is the voltage phase of the AC power supply. Control is performed so as to proceed from (a state in which the phase of the control signal changes first in time). The AC power supplied to the inductive load can be controlled by changing the phase difference between the voltage phase of the control signal and the AC power supply in accordance with the purpose / range of control.

 Furthermore, the power converter circuit (hereinafter referred to as the “MERS resonant inverter” circuit) that takes advantage of the features of the AC control device using MERS, such as resonance of inductive load and capacitor, and soft switching operation of reverse conducting semiconductor elements. Has been proposed and published, and is already publicly known (see Patent Document 3).

 The M E R S resonant inverter circuit uses a direct current source as a power source and can provide alternating vibration current to an inductive load. That is, it can be used as a direct current / AC power conversion circuit.

The MERS resonant inverter circuit includes a first reverse conducting semiconductor switch leg having a first AC terminal at a point connecting the negative side of the first reverse conducting semiconductor switch and the positive side of the second reverse conducting semiconductor switch. A second reverse conducting semiconductor switch leg having a second AC terminal at a point where the negative side of the third reverse conducting semiconductor switch and the positive side of the fourth reverse conducting semiconductor switch are connected, The positive side of the first reverse conduction type semiconductor switch and the positive electrode of the third reverse conduction type semiconductor switch are connected to each other as a positive terminal, and the second reverse conduction type semiconductor switch and the fourth reverse conduction type semiconductor are connected. It consists of a full-bridge circuit configured as a negative terminal by connecting the negative electrodes of the switch, and a capacitor connected between the positive and negative terminals of the full-bridge circuit. The capacitance of the capacitor is the capacitance that resonates with the inductance of the inductive load, and the resonance frequency determined by the capacitance of the capacitor and the inductance of the inductive load is the target AC oscillation current. The capacity is selected so as to be equal to or higher than the frequency. The first reverse-conducting semiconductor switch and the fourth reverse-conducting semiconductor switch are the first pair, the second reverse-conducting semiconductor switch and the third reverse-conducting semiconductor switch are the second pair, and the first pair When the first pair is on, the second pair is turned off. When the first pair is off, the second pair is turned on. Controls the on / off state of.

 Assuming that the switching frequency of the reverse conducting semiconductor switch is equal to or less than the frequency of the target AC oscillating current, when the reverse conducting semiconductor switch is turned on, the self-extinguishing element constituting the reverse conducting semiconductor switch is When the switch is turned off, the self-extinguishing element constituting the reverse conduction type semiconductor switch can perform a soft switching operation with a substantially zero voltage.

In the MERS resonant inverter circuit, the DC current source is connected between the positive and negative terminals of the full-bridge circuit (both ends of the capacitor), and the inductive load is between the first AC terminal and the second AC terminal of the full-bridge circuit. It takes the form of connecting to. The ON / OFF time ratio (duty ratio) of the reverse conducting semiconductor switch is 0.5, that is, the ON time and OFF time are equal. The DC current source can be realized by rectifying a commercial AC power supply and then connecting it via a smoothing DC reactor, or by connecting a DC voltage source via a DC reactor. In the ME RS resonant inverter circuit, a current in phase with the voltage phase flows. When a DC current source is created from a commercial AC power supply, a circuit close to a power factor of 1 is connected from the commercial AC power supply.

 In the ME RS resonant inverter circuit, the capacitor absorbs the magnetic energy stored in the inductive load due to resonance between the capacitor and the inductance component of the inductive load (the capacitor is charged) and regenerates to the inductive load (capacitor Is discharged) and reused. In addition, since the power supplied from the DC current source only needs to be consumed by the resistance component of the inductive load, the current capacity of the feeder line from the DC current source to the ME RS resonant inverter circuit can be small. There is also.

 [Patent Document 1] Japanese Patent No. 3 6 3 4 9 8 2

 [Patent Document 2] Japanese Patent No. 3 7 3 5 6 7 3

 [Patent Document 3] International Application Publication Number WO 2 0 0 8 Z 0 4 4 5 1 2 Pan Fretz の Summary of the Invention

Problems to be solved by the invention

The ME RS resonant inverter circuit is highly controllable and can operate stably. The capacitor is charged and discharged by resonating with the inductance component of the inductive load. When the capacitor charges and discharges, current flows through at least two reverse conducting semiconductor switches. When the power factor of the inductive load is poor (the phase difference between the voltage and current is large), the current passing through the reverse conducting semiconductor switch is the current equivalent to the apparent power flowing through the inductive load (hereinafter referred to as “load current”). Amount). Induct the ME RS resonant inverter circuit When applied to a device that requires a large amount of power because the power factor of an inductive load such as a power supply for heating is low, the conduction loss in the reverse conduction type semiconductor switch increases, and the low loss characteristic of soft switching operation May reduce the benefits of low heat generation.

 The present invention has been made to alleviate the above-described problems, and an object of the present invention is to provide a M E R S resonant inverter circuit having a simple circuit configuration by reducing the number of reverse conducting semiconductor switches to be used. Means for solving the problem

 The present invention relates to a power conversion device that converts DC power into AC power.

A circuit in which the self-extinguishing element and the diode are connected to the positive side of the self-extinguishing element and the negative side of the diode, and the negative side of the self-extinguishing element is connected to the positive side of the diode, or An equivalent semiconductor element is a reverse-conducting semiconductor switch (hereinafter simply referred to as “reverse conducting semiconductor switch”), and a first capacitor short-circuit circuit in which a first reverse-conducting semiconductor switch and a first capacitor are connected in parallel. And a second capacitor short circuit, in which the second reverse conducting semiconductor switch and the second capacitor are connected in parallel, are connected to the negative side of the self-extinguishing element constituting the first reverse conducting semiconductor switch ( (Hereinafter referred to simply as “the negative side of the reverse conducting semiconductor switch”) and the negative terminal of the second reverse conducting semiconductor switch, the two-capacitor horizontal half-type MERS circuit having the negative terminal and the first DC reactor Toru The DC reactor circuit with the positive DC terminal connected to the second DC reactor is connected to the positive side of the self-extinguishing element constituting the first reverse conducting semiconductor switch (hereinafter simply referred to as “reverse conducting type”). The point where the positive electrode side of the semiconductor switch is connected to the other end of the first DC reactor is the first AC terminal, and the positive side of the second reverse conducting semiconductor switch is connected to the second DC terminal. A two-capacitor horizontal half-bridge circuit configured as a second AC terminal at the point where the other end of the flow reactor is connected,

 A DC voltage source connected between the positive terminal and the negative terminal of the two-capacitor horizontal half-type bridge circuit;

 An inductive load connected between the first AC terminal and the second AC terminal of the two-capacitor horizontal half bridge circuit;

 A control means, and

 When the self-extinguishing element constituting the first reverse conducting semiconductor switch is in the conducting state (hereinafter simply referred to as “the reverse conducting semiconductor switch is turned on”), the control means When the self-extinguishing element constituting the conductive semiconductor switch is in the blocking state (hereinafter simply referred to as “the reverse conductive semiconductor switch is turned off”), and the first reverse conductive semiconductor switch is in the off state, The second reverse conducting semiconductor switch is turned on so that the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are not turned on at the same time. Control the Z-off state,

Furthermore, the control means is that the switching frequency (fsw) of on-off of the reverse conducting semiconductor switch is determined by the inductance (L) of the inductive load and the capacitance (C 1) of the first capacitor. The lower frequency of the resonance frequency (fres 1) and the second resonance frequency (fres 2) determined by the inductance (L) of the inductive load and the capacitance (C 2) of the second capacitor When the reverse conducting semiconductor switch is turned on by controlling the ON / OFF state of the reverse conducting semiconductor switch so that the following is true, the self-extinguishing element constituting the reverse conducting semiconductor switch is substantially zero. The self-extinguishing element that constitutes the reverse conducting semiconductor switch is turned off by a power conversion device characterized by performing a soft switching operation of substantially zero voltage when it is turned off. It is made. Also, the above object of the present invention is to

 A first capacitor short circuit in which the first reverse conduction type semiconductor switch and the first capacitor are connected in parallel, and a second capacitor short circuit in which the second reverse conduction type semiconductor switch and the second capacitor are connected in parallel A two-capacitor horizontal half-type ME RS circuit with the negative terminal connected to the negative side of the first reverse conducting semiconductor switch and the negative side of the second reverse conducting semiconductor switch, and the first inductive The inductive load circuit with the positive terminal as the point where the load and the second inductive load are connected is the point where the positive side of the first reverse conducting semiconductor switch and the other end of the first inductive load are connected. A two-capacitor horizontal half that is configured as a second AC terminal that is the first AC terminal and the point where the positive electrode side of the second reverse conducting semiconductor switch is connected to the other end of the second inductive load Type bridge circuit,

 A DC current source connected between the positive terminal and the negative terminal of the two-capacitor horizontal half-type bridge circuit;

 A control means, and

 When the first reverse conducting semiconductor switch is on, the control means sets the second reverse conducting semiconductor switch to off, and when the first reverse conducting semiconductor switch is off. The second reverse conducting semiconductor switch is turned on so that the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are not turned on at the same time. Control the on / off state of the

In addition, the control means is such that the switching frequency (fsw) of the reverse conduction type semiconductor switch on Z-off is the inductance (L 1) of the first inductive load and the inductance (L 2) of the second inductive load. The first resonant frequency (fresl) determined by the combined inductance (L 1 + L 2) and the capacitance of the first capacitor (C 1), and the combined inductance (L 1 + L 2) Control the ON / OFF state of the reverse conducting semiconductor switch so that it is below the second resonance frequency (fres 2) determined by the capacitance (C 2) of the second capacitor. When the reverse conducting semiconductor switch is turned on, the self-extinguishing element constituting the reverse conducting semiconductor switch is at substantially zero voltage and zero current, and when turned off, the reverse conducting semiconductor is The self-extinguishing element constituting the switch is achieved by a power conversion device characterized by performing a soft switching operation of substantially zero voltage.

 Also, the above object of the present invention is to

 When a field-effect transistor or a semiconductor element having an equivalent structure is used as the self-extinguishing element constituting the reverse conducting semiconductor switch, the control means This can also be achieved by a power converter characterized by controlling the arc extinguishing element to be in a conductive state.

 Also, the above object of the present invention is to

The first reverse-conducting semiconductor switch and the second reverse-conducting semiconductor switch are connected to the negative terminal of the point where the negative side of the first reverse-conducting semiconductor switch is connected to the negative side of the second reverse-conducting semiconductor switch. The first AC terminal is the point where one end of the capacitor is connected to the positive side of the first reverse-conducting semiconductor switch, and the other end of the capacitor is the second reverse polarity. The point where the point connected to the positive side of the conductive semiconductor switch is used as the second AC terminal, and the point where the 1-capacitor horizontal half-type MERS circuit is connected to the first DC reactor and the second DC reactor. Connect the other end of the first DC reactor to the first AC terminal, and connect the other end of the second DC reactor to the second AC terminal. 1 capacitor And the half-type bridge circuit, 1 DC voltage source connected between the positive terminal and the negative terminal of the capacitor horizontal half-type wedge circuit;

 1 An inductive load connected between the first AC terminal and the second AC terminal of the capacitor horizontal half-ply circuit,

 A control means, and

 When the first reverse conducting semiconductor switch is in the on state, the control means sets the second reverse conducting semiconductor switch in the off state, and when the first reverse conducting semiconductor switch is in the off state. The second reverse conducting semiconductor switch is turned on so that the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are not turned off at the same time. Control the on / off state of the

 Furthermore, the control means is that the switching frequency (fsw) of the reverse conducting semiconductor switch is determined by the resonance frequency (fres) determined by the inductance (L) of the inductive load and the capacitance (C) of the capacitor. When the reverse conducting semiconductor switch is turned on and off by controlling the on / off state of the reverse conducting semiconductor switch so that the following is true, the self-extinguishing element constituting the reverse conducting semiconductor switch is: This is achieved by a power conversion device characterized by performing a soft switching operation at substantially zero voltage.

 Also, the above object of the present invention is to

The first reverse-conducting semiconductor switch and the second reverse-conducting semiconductor switch are connected to the negative terminal of the point where the negative side of the first reverse-conducting semiconductor switch is connected to the negative side of the second reverse-conducting semiconductor switch. The first AC terminal is the point where one end of the capacitor is connected to the positive side of the first reverse-conducting semiconductor switch, and the other end of the capacitor is the second reverse polarity. A 1-capacitor horizontal half-type MERS circuit configured as the second AC terminal at the point connected to the positive side of the conductive semiconductor switch, and the first induction Connect the inductive load circuit with the positive terminal at the point where the conductive load and the second inductive load are connected, connect the positive side of the first reverse conducting semiconductor switch and the other end of the first inductive load, And a 1-capacitor side-by-side bridge circuit configured by connecting the positive electrode side of the second reverse conducting semiconductor switch and the other end of the second inductive load;

 1 DC current source connected between the positive and negative terminals of the capacitor horizontal half-type

 A control means, and

 When the first reverse conducting semiconductor switch is in the on state, the control means sets the second reverse conducting semiconductor switch in the off state, and when the first reverse conducting semiconductor switch is in the off state. The second reverse conducting semiconductor switch is turned on so that the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are not turned off at the same time. Control the on / off state of the

 Furthermore, the control means is such that the switching frequency (: fsw) of the ON-Z OFF of the reverse conducting semiconductor switch is such that the inductance (L 1) of the first inductive load and the inductance (L 2) of the second inductive load By controlling the on / off state of the reverse conducting semiconductor switch so that it is less than the resonance frequency (fres) determined by the combined inductance (L 1 + L 2) and the capacitance (C) of the capacitor, When the reverse conducting semiconductor switch is turned on / off, the self-extinguishing element constituting the reverse conducting semiconductor switch is achieved by a power conversion device characterized by performing a soft switching operation of substantially zero voltage. .

Furthermore, the above object of the present invention is to This is achieved by a power converter characterized by using polar capacitors for the first capacitor and the second capacitor of the power converter described above.

 Furthermore, the above object of the present invention is to

Reverse the connection polarity of the DC voltage source of the above power converter,

The connection polarity of the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are reversed,

 Furthermore, when the first capacitor and the second capacitor are polar capacitors, this can also be achieved by a power converter characterized by reversing the connection polarity of each.

 Furthermore, the above object of the present invention is to

Reverse the connection polarity of the direct current source of the above power converter,

The connection polarity of the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are reversed,

 Furthermore, when the first capacitor and the second capacitor are polar capacitors, this can also be achieved by a power converter characterized by reversing the connection polarity of each.

 Furthermore, the above object of the present invention is to

In place of the inductive load circuit having the positive terminal at the point where the first inductive load and the second inductive load of the power converter described above are connected,

This is achieved by a power converter characterized by replacing an inductive load with a tap and using one tap as the positive terminal.

 Furthermore, the above object of the present invention is to

In place of the inductive load circuit having the positive terminal at the point where the first inductive load and the second inductive load of the power converter described above are connected, This is achieved by a power conversion device characterized in that it is replaced with a coupling transformer with taps, and one tap is used as a positive terminal, and matching is performed with an inductive load that does not have a tapping.

 Furthermore, the above object of the present invention is to

In place of the direct current source of the above power converter,

A DC voltage source;

A DC reactor connected to a DC voltage source;

This is achieved by a power conversion device characterized in that

 Furthermore, the above object of the present invention is to

In place of the direct current source of the above power converter,

AC power supply,

A rectifier circuit;

It is achieved by a power conversion device characterized by replacing with an AC reactor connected between an AC power source and an AC terminal of a rectifier circuit.

 Furthermore, the above object of the present invention is to

In place of the direct current source of the above power converter,

AC power supply,

A Siris evening AC power adjustment device, one end of which is connected to an AC power source,

 A high-impedance transformer whose primary side is connected to the other end of the AC power regulator,

Replace the AC terminal with a rectifier circuit connected to the secondary side of the high-impedance transformer,

 Further, the power conversion device is characterized in that the control means sends a control signal to the thyris AC power adjustment device and adjusts the amount of AC oscillating current supplied to the inductive load.

Furthermore, the above object of the present invention is to In place of the DC voltage source of the above power converter,

A rectifier circuit;

An AC power source connected between AC terminals of the rectifier circuit;

This is achieved by a power conversion device characterized in that

 Furthermore, as an inductive load of the above-described power converter, an induction coil for inductively heating an object to be heated is used.

It is possible to provide an induction heating power supply device characterized in that the frequency of the AC oscillating current supplied to the induction coil is variable according to the object and purpose of the object to be heated.

 In addition, an induction coil for induction heating the object to be heated,

A power supply device for induction heating described above,

It is possible to provide an induction heating device that performs induction heating by supplying an alternating vibration current to the induction coil from the power supply device for induction heating. The invention's effect

 According to the power conversion device of the present invention, an AC oscillating current having a variable frequency can be supplied to an inductive load only by a magnetic energy regenerative switch.

 Also, only two reverse conducting semiconductor switches are required.

Also, in a circuit with two capacitors, when turning on the reverse conducting semiconductor switch, the self-extinguishing element constituting the reverse conducting semiconductor switch is turned off at substantially zero voltage and zero current. The self-extinguishing element that constitutes the reverse conducting semiconductor switch is a soft switching operation with substantially zero voltage, and in a circuit with one capacitor, the reverse conducting semiconductor switch is turned on z off. The self-extinguishing element that constitutes the reverse conducting semiconductor switch is assumed to have a soft switching operation with a substantially zero voltage. It is possible to reduce switching loss in a reverse conducting semiconductor switch.

 Also, with one capacitor, the current flowing through the reverse conducting semiconductor switch is reduced, and conduction loss can be reduced.

 Further, in any configuration, since the negative electrode sides or the positive electrode sides of the two reverse conducting semiconductor switches are common, there are many effects that the control means for driving the reverse conducting semiconductor switches can be simplified. Brief Description of Drawings

 FIG. 1 is a circuit block diagram showing the configuration of the first embodiment according to the present invention.

 FIG. 2 is a circuit block diagram showing the configuration of the second embodiment according to the present invention.

 FIG. 3 is a circuit block diagram showing the configuration of the third embodiment according to the present invention.

 FIG. 4 is a circuit block diagram showing the configuration of the fourth embodiment according to the present invention.

FIG. 5 is a circuit block diagram showing a configuration in which the positive electrode sides of two reverse conducting semiconductor switches are shared in the first embodiment according to the present invention. FIG. 6 is a circuit block diagram showing a configuration in which the positive electrode sides of two reverse conducting semiconductor switches are shared in the second embodiment according to the present invention. FIG. 7 is a circuit block diagram showing a configuration in which the positive electrode sides of two reverse conducting semiconductor switches are shared in the third embodiment according to the present invention. FIG. 8 is a circuit block diagram showing a configuration in which the positive electrode sides of two reverse conducting semiconductor switches are shared in the fourth embodiment according to the present invention. FIG. 9 is a circuit block diagram showing a case where the first inductive load and the second inductive load are replaced with inductive loads having taps in the second embodiment according to the present invention.

 FIG. 10 is a circuit block diagram showing a case where the DC current source is replaced with a DC voltage source and a DC reactor connected to the DC voltage source in the second embodiment according to the present invention.

 FIG. 11 is a circuit block diagram showing a case where the direct current source is replaced with a direct current voltage source and a direct current reactor connected to the direct current voltage source in the fourth embodiment according to the present invention.

 FIG. 12 (A) is a circuit block diagram showing another configuration of the direct current source in each of the power conversion devices of the second and fourth embodiments according to the present invention.

 FIG. 12 (B) is a circuit block diagram showing still another configuration of the direct current source in each of the power conversion devices of the second and fourth embodiments according to the present invention.

 FIG. 12 (C) is a circuit block diagram showing a DC voltage source.

 FIG. 12 (D) is a circuit block diagram showing another configuration of the DC voltage source.

 FIG. 13 is a diagram showing a computer simulation result (switching frequency is 500 Hz) of the configuration of the first embodiment and the second embodiment according to the present invention.

 FIGS. 14 (A) to (F) are circuit block diagrams for explaining the operation principle of the first embodiment according to the present invention.

FIGS. 15 (A) to (F) are circuit block diagrams for explaining the operation principle of the second embodiment according to the present invention. FIG. 16 is a diagram showing a computer simulation result (switching frequency is 500 Hz) of the configuration of the third embodiment and the fourth embodiment according to the present invention.

 FIGS. 17 (A) to (F) are circuit block diagrams for explaining the operation principle of the third embodiment according to the present invention.

 FIGS. 18 (A) to (F) are circuit block diagrams for explaining the operation principle of the fourth embodiment according to the present invention.

 FIG. 19 is a diagram showing computer simulation results (switching frequency is 200 Hz) of the configuration of the first embodiment and the second embodiment according to the present invention.

 FIG. 20 is a view showing a computer simulation result (a switching frequency is 200 Hz) of the configuration of the third embodiment and the fourth embodiment according to the present invention.

 FIG. 21 is a circuit block diagram showing the M E R S resonant inverter circuit.

 Figure 22 shows the results of computer simulation of the M E R S resonant inverter circuit. Explanation of symbols

 DC voltage source

 DC current source

 AC source

 Control means

 Inductive load

 First inductive load

Second inductive load 8 Inductive load with tap

1 0 Full bridge circuit

 1 1 2 3Denser horizontal half-fridge circuit

 1 2 2 Other side of the capacitor-side bridge-another type of bridge circuit

2 1 1 3 sensor horizontal half-type bridge circuit

 2 2 1 Another aspect of capacitor horizontal half bridge circuit

AC 1 _i AC terminal

 A C 2 Second AC terminal

 D C P Positive terminal

 D C N Negative electrode

G 1 i reverse conduction semiconductor switch gain control signal

G 2 Second reverse conducting semiconductor switch gain control signal

G 3 Gate control signal for the third reverse conducting semiconductor switch

G 4 reverse conducting semiconductor switch

^4th glance control signal

S W 1 i reverse conducting semiconductor switch

 S W 2 Second reverse conducting semiconductor switch

 S W 3 3rd reverse conducting semiconductor switch

 S W 4 reverse conducting semiconductor switch

^4th

L a c AC reactor

HIT r high impedance transformer L dc DC reactor

 L d c 1 First DC reactor

 L d c 2 Second DC reactor

C capacitor

 C 1 first capacitor

 C 2 Second capacitor

 R B Rectifier circuit

 T h Thyristor AC Power Conditioner

L Inductive load inductance component

 L 1 Inductance component of the first inductive load

 L 2 Inductance component of the second inductive load

 L 1 + L 2 Combined inductance component of the inductance component of the first inductive load and the inductance component of the second inductive load

R Resistance component of inductive load

R 1 Resistance component of the first inductive load

R 2 Resistance component of the second inductive load

R 1 + R 2 Combined resistance component of the resistance component of the first inductive load and the resistance component of the second inductive load

I s w 1 Current passing through the first reverse conducting semiconductor switch

 I s w 2 Current passing through the second reverse conducting semiconductor switch

I 1 oad Inductive load / inductive load circuit Current flowing through an inductive load with Z tap (load current) V c Voltage across capacitor

 V c 1 Voltage across first capacitor

 V c 2 Voltage across the second capacitor

V I o a d Inductive load Z Inductive load circuit Voltage applied to inductive load with Z tap

V s w 1 Voltage applied to the first reverse conducting semiconductor switch

 V s w 2 Voltage applied to the second reverse conducting semiconductor switch

 V s w 3 Voltage applied to the third reverse conducting semiconductor switch

 V s w 4 Voltage applied to the 4th reverse conducting semiconductor switch

(f s w) Switching frequency of reverse conducting semiconductor switch

 (f r e s) Resonance frequency

 (f r e s 1) 1st resonance frequency

 (f r e s 2) Second resonance frequency

 (C) Capacitor capacitance

 (C 1) Capacitance of the first capacitor

 (C 2) Capacitance of the second capacitor

 (L) Inductive load inductance

 (L 1) Inductance of the first inductive load

 (L 2) Inductance of second inductive load

 (L 1 + L 2) Combined inductance of the inductance of the first inductive load and the inductance of the second inductive load

 (R) Inductive load equivalent resistance

(R 1) Equivalent resistance of the first inductive load (R 1) Equivalent resistance of second inductive load

 (R 1 + R 2) Combined equivalent resistance of the equivalent resistance of the first inductive load and the equivalent resistance of the second inductive load

 (L d c) Inductance of DC reactor

 (L d c l) Inductance of the first DC reactor

 (L d c 2) Inductance of second DC reactor Mode for carrying out the invention

 Embodiments according to the present invention will be described below with reference to the drawings. The same components, members, and processes shown in the drawings are given the same reference numerals, and repeated descriptions are omitted as appropriate. Further, the embodiments are examples, not limiting the invention, and all features and combinations described in the embodiments are not necessarily essential to the invention. .

 In the following, a self-extinguishing element indicates an electronic component capable of controlling the forward conduction state and blocking state of the element by applying a control signal to the gate of the element.

 [Embodiment 1] Two-capacitor horizontal half-type M ERS resonant inverter circuit FIG. 1 is a circuit block diagram showing a configuration of a power converter according to a first embodiment of the present invention.

In more detail, Fig. 1 shows the connection between the self-extinguishing element and the diode, the positive side of the self-extinguishing element and the negative side of the diode, and the negative side of the self-extinguishing element and the positive side of the diode. The connected circuit or equivalent semiconductor element is formed as a reverse conducting semiconductor switch (hereinafter simply referred to as “reverse conducting semiconductor switch”), and the first reverse conducting semiconductor switch SW 1 and the first capacitor C 1 are connected in parallel. A first capacitor short circuit connected to the second reverse conducting half The second capacitor short circuit, in which the conductor switch SW2 and the second capacitor C2 are connected in parallel, is connected to the negative side of the self-extinguishing element constituting the first reverse conducting semiconductor switch SW1 (hereinafter simply “ 2 capacitor lateral half type ME RS circuit with the negative terminal DCN as the point connecting the negative side of the second reverse conducting semiconductor switch SW 2 and the first DC A DC reactor circuit with the positive terminal DCP at the point where reactor L dc 1 and second DC reactor L dc 2 are connected is connected to the self-extinguishing element constituting the first reverse conducting semiconductor switch SW 1. The point at which the positive electrode side (hereinafter simply referred to as “the positive electrode side of the reverse conducting semiconductor switch”) and the other end of the first DC reactor L dc 1 are connected is the first AC terminal AC 1, and the second Reverse conduction type semiconductor switch SW2 positive side and second DC rear Two-capacitor horizontal half-type bridge circuit 1 1 and two-capacitor horizontal half-type bridge circuit 1 1 are configured as the second AC terminal AC 2 at the point where the other end of the coil L dc 2 is connected DCP DC voltage source 1 connected between the DCN and the negative terminal DCN, and inductivity connected between the first AC terminal AC 1 and the second AC terminal AC 2 of the 2-capacitor horizontal half-bridge circuit 1 1 Load 5 and control. Means 4 and

When the self-extinguishing element constituting the first reverse conducting semiconductor switch SW 1 is in the conducting state (hereinafter simply referred to as “the reverse conducting semiconductor switch is turned on”), the control means 4 The self-extinguishing type semiconductor switch constituting the reverse conducting semiconductor switch SW 2 is blocked (hereinafter simply referred to as “the reverse conducting semiconductor switch is turned off”), and the first reverse conducting semiconductor switch SW 1 is in the off state. In this case, the second reverse conducting semiconductor switch SW2 is turned on, and the first reverse conducting semiconductor switch SW1 and the second reverse conducting semiconductor switch SW2 are not turned on at the same time. To control the ON / OFF state of the reverse conducting semiconductor switch, Furthermore, the control means 4 has an on / off switching frequency (fsw) of the reverse conducting semiconductor switch that is determined by the inductance (L) of the inductive load 5 and the capacitance (C 1) of the first capacitor C 1. Determined first resonance frequency

 (fresl, l / 27 T (L) (C 1)), and the second resonant frequency (which is determined by the inductance (L) of the inductive load 5 and the capacitance (C 2) of the second capacitor C 2 ( fres 2, \ / 2% (L) (C 2)) The reverse conduction type semiconductor switch is controlled by controlling the ON Z-off state of the reverse conduction type semiconductor switch so that it is lower than the lower frequency. The self-extinguishing element that constitutes the reverse conducting semiconductor switch is turned on at substantially zero voltage and zero current, and the self-extinguishing element that constitutes the reverse conducting semiconductor switch when turned off. Is characterized by soft switching operation at approximately zero voltage.

 Next, the operation principle of the power conversion device according to the first embodiment of the present invention will be described with reference to FIG. 13 and FIGS. 14 (A) to 14 (F).

 Figure 13 is the circuit block diagram shown in Figure 1 and shows the computer simulation results when the following circuit constants are used.

<Circuit constants in Fig. 13>

DC voltage source 1 voltage: 1 0 0 V,

Inductance of first DC reactor L d c l (L d c l): 1 m H,

Inductance of second DC reactor L d c 2 (L d c 2): 1 m H,

Capacitance of the first capacitor (C 1): 5 0 0 micro F,

Capacitance of the second capacitor (C 2): 500 micro F,

Inductive load 5 inductance (L): 1 0 0 micro H

Inductive load 5 equivalent resistance (R): 0.0 4 3 ohm, Switching frequency (fsw) of reverse conducting semiconductor switch: 5 0 00 Hz. More specifically, Fig. 13 shows the current flowing through the inductive load (load current) I load, the voltage VI oad applied to the inductive load, the voltage V applied to the first reverse conducting semiconductor switch SW 1 sw 1 (equal to the voltage V c 1 across the first capacitor C 1), the voltage V sw 2 applied to the second reverse conducting semiconductor switch SW 2 (the voltage V c 2 across the second capacitor C 2 Current I sw 1 passing through the first reverse conducting semiconductor switch SW 1, current I sw 2 passing through the second reverse conducting semiconductor switch SW 2, and the first reverse conducting semiconductor switch SW 1 The waveforms of the gate control signal G 1 and the gate control signal G 2 of the second reverse conducting semiconductor switch SW 2 are shown. The current flowing through the inductive load (load current) I 1 oad expresses the direction flowing from the first AC terminal AC 1 to the second AC terminal AC 2 as positive. The DC voltage source 1 continuously supplies a DC current to the inductive load 5 through the first DC reactor L dc 1 and the second DC reactor L dc 2 (hereinafter simply referred to as “supply current”). "). Each section divided by (a) to (f) in Fig. 13 corresponds to the respective states in Fig. 14 (A) to Fig. 14 (F). FIGS. 14 (A) to 14 (F) are for explaining the principle of operation, and the control means 4 is not shown. Inductive load 5 shows only an inductance component L and a resistance component R. The arrow indicates the current and its direction, and the thickness of the arrow indicates the magnitude of the current. However, the arrow thickness is relative.

 As an initial condition, it is assumed that the first capacitor C 1 and the second capacitor C 2 are not charged and the inductive load 5 stores the magnetic energy of the current.

1) When the control means 4 turns on the first reverse conducting semiconductor switch SW1 and at the same time turns off the second reverse conducting semiconductor switch SW2, 1 Section (a) in Figure 3 and state in Figure 14 (A). The second capacitor C2 is charged by the supply current. Furthermore, the current flowing by the magnetic energy of the inductive load 5 is interrupted by the second reverse conducting semiconductor switch SW 2, and as a result, the second capacitor C 2 is charged.

 2) Eventually, the section shown in Fig. 13 (b) and Fig. 14 (B) is reached. Due to resonance between the inductance component L of the inductive load 5 and the second capacitor C 2, the electric power stored in the second capacitor C 2 is discharged to the inductive load 5. When the electric power stored in the second capacitor C2 is discharged and disappears, the voltage across the second capacitor C2 becomes approximately 0 [V], and no current flows through the second capacitor C2.

 3) Then, the section (c) in Fig. 13 and the state shown in Fig. 14 (C) are obtained. The current that flows due to the magnetic energy stored in the inductive load 5 flows as shown by the arrow indicating the load current in Fig. 14 (C). At this time, a load current flows through the self-extinguishing element of the first reverse conducting semiconductor switch SW1 and the diode of the second reverse conducting semiconductor switch SW2.

 4) Subsequently, when the control means 4 turns off the first reverse conducting semiconductor switch SW 1 and at the same time turns on the reverse conducting semiconductor switch SW2, the section (d) in FIG. The state shown in (D) is obtained. The first capacitor C 1 is charged by the supply current. Furthermore, the current flowing by the magnetic energy of the inductive load 5 is interrupted by the first reverse conducting semiconductor switch SW2, and as a result, the first capacitor C1 is charged.

5) Eventually, the section shown in Fig. 13 (e) and Fig. 14 (E) is reached. Due to the resonance between the inductance component L of the inductive load 5 and the first capacitor C 1, the electric power stored in the first capacitor C 1 is discharged to the inductive load 5. The power stored in the first capacitor C 1 is not discharged Then, the voltage across the first capacitor C 1 becomes approximately 0 [V], and no current flows through the first capacitor C 1.

 6) Then, the section shown in Fig. 13 (ί) and the status shown in Fig. 14 (F) are obtained. The current that flows due to the magnetic energy stored in the inductive load 5 flows as shown by the arrow indicating the load current in Fig. 14 (F). At this time, a load current flows through the diode of the first reverse conducting semiconductor switch SW 1 and the self-extinguishing element of the second reverse conducting semiconductor switch SW 2.

 7) Subsequently, when the control means 4 turns on the first reverse conducting semiconductor switch SW 1 and at the same time turns off the second reverse conducting semiconductor switch SW 2, the section shown in FIG. (A) The state shown in Fig. 14 (A) is obtained. The power conversion device according to the first embodiment of the present invention can apply the alternating vibration current to the inductive load 5 by repeating the above-described operation in a steady state.

Next, features of the power conversion device according to the first embodiment of the present invention will be described. The capacitance (C 1) of the first capacitor C 1 and the capacitance (C 2) of the second capacitor C 2 are in resonance with the inductance (L) of the inductive load 5, respectively. An extremely small capacity is sufficient to absorb and release 5 magnetic energy. In other words, the first capacitor C 1 and the second capacitor C 2 have a capacity suitable for absorbing and discharging only half the period of the AC oscillation current supplied to the inductive load 5. The capacity and purpose are completely different from the large-capacity smoothing capacitor used to stably supply the DC voltage used in the inverter circuit. Since the first capacitor C 1 and the second capacitor C 2 are alternately charged and discharged, the current duty per capacitor is halved compared to the MERS resonant inverter circuit. The first capacitor C 1 and the second capacitor Since the polarity of the capacitor C 2 is always constant when the capacitor is charged and discharged, a polar capacitor can be used.

 The on / off switching frequency (fsw) of the reverse conducting semiconductor switch is determined by the inductance (L) of the inductive load 5 and the capacitance (C 1) of the first capacitor C 1. Resonance frequency (fresl, 1/2 (L) (CI)), second resonance frequency determined by inductance (L) of inductive load 5 and capacitance of second capacitor C2 (C2)

 The reverse conducting semiconductor switch is turned on by controlling the on / off state of the reverse conducting semiconductor switch so that it is below the lower frequency of (fres 2, \ / 2 (L) (C 2)). The self-extinguishing element constituting the reverse conducting semiconductor element is substantially zero voltage and substantially zero current, and the self-extinguishing type element constituting the reverse conducting semiconductor element when turned off. The element can be in a soft switching operation at approximately zero voltage. As long as this condition is satisfied, the frequency of the alternating oscillating current supplied to the inductive load 5 can be made variable by controlling the switching frequency of the reverse conducting semiconductor switch.

 Also, the AC oscillating current supplied to the inductive load 5 consumes energy in the resistance component R of the inductive load 5 and the current is attenuated. Injection of the consumed energy is performed by the DC voltage source 1 that has been made “DC current source” via the first DC reactor L dc 1 and the second DC reactor L dc 2. That is, since the power supplied from the DC voltage source 1 only needs to be consumed by the resistance component R of the inductive load 5, the power converter of the first embodiment according to the present invention from the DC voltage source 1 The current capacity of the power supply line to is small.

Further, the power conversion device according to the first embodiment of the present invention has as few as two reverse conducting semiconductor switches. In addition, the first reverse conducting semiconductor switch SW Since the negative electrode side of 1 and the negative electrode side of the second reverse conducting semiconductor switch SW 2 are connected, there is no need to insulate the circuits that drive the gates of the respective reverse conducting semiconductor switches. You can also share power.

 In addition, the DC voltage source 1 has a feature that half of the voltage of the DC current source 2 of the M E R S resonant inverter circuit is sufficient to obtain the voltage of the AC oscillating current supplied to the inductive load 5.

 Furthermore, when a field effect transistor or a semiconductor element having an equivalent structure is used as a self-extinguishing element constituting a reverse conduction type semiconductor switch, the control means is configured such that when the diode becomes conductive in the forward direction. If the self-extinguishing element is controlled to be in a conductive state, a synchronous rectification method can be used to reduce conduction loss.

 [Example 2] Two-capacitor horizontal half-shaped M E R S resonant inverter circuit deformation pattern

 FIG. 2 is a circuit block diagram showing the configuration of the power conversion device according to the second embodiment of the present invention.

More specifically, FIG. 2 shows a first capacitor short-circuit circuit in which a first reverse conducting semiconductor switch SW 1 and a first capacitor C 1 are connected in parallel, a second reverse conducting semiconductor switch SW 2, and Connect the second capacitor short circuit with the second capacitor C 2 connected in parallel to the negative side of the first reverse conducting semiconductor switch SW 1 and the negative side of the second reverse conducting semiconductor switch SW 2. The inductive load circuit with the positive terminal DCP as the point where the two-capacitor horizontal half-type MERS circuit with the negative terminal DCN and the first inductive load 6 and the second inductive load 7 are connected The point where the positive polarity side of the reverse conduction type semiconductor switch SW 1 is connected to the other end of the first inductive load 6 is the first AC terminal AC 1 and the second reverse conduction type semiconductor switch SW 2 Positive side and second invitation The point where the other end of the conductive load 7 is connected is the second AC terminal AC 2, and the positive terminal of the 2-capacitor horizontal half-bridge circuit 1 2 and 2-capacitor horizontal-half bridge circuit 1 2 DCP A direct current source 2 connected between the negative terminal DCN and a control means 4, and

 When the first reverse conducting semiconductor switch SW 1 is in the on state, the control means 4 sets the second reverse conducting semiconductor switch SW 2 in the off state, and the first reverse conducting semiconductor switch SW 1 is in the off state. In the off state, the second reverse conducting semiconductor switch SW2 is turned on, and the first reverse conducting semiconductor switch SW1 and the second reverse conducting semiconductor switch SW2 are turned on simultaneously. The ON / OFF state of the reverse conducting semiconductor switch is controlled so that the

 Further, the control means 4 is configured such that the switching frequency (fsw) of the on-off of the reverse conducting semiconductor switch is such that the inductance (L 1) of the first inductive load 6 and the inductance of the second inductive load 7 The first resonance frequency (fres 1, 1/2 (L 1 + L 2) determined by the combined inductance (L 1 + L 2) of (L 2) and the capacitance (C 1) of the first capacitor C 1 ) (C

1)) and the second resonant frequency (fres 2, 1/2 π (L 1 + L 2) determined by the combined inductance (L 1 + L 2) and the capacitance (C 2) of the second capacitor C 2 ) (C 2) When the reverse conducting semiconductor switch is turned on by controlling the on / off state of the reverse conducting semiconductor switch so that it is lower than the lower frequency, the reverse conducting semiconductor switch The self-extinguishing element that constitutes the power supply is substantially zero voltage and zero current, and when turned off, the self-extinguishing element constituting the reverse conducting semiconductor switch is soft switching that is substantially zero voltage. It is characterized by operation. The operation of the power converter of the second embodiment according to the present invention is the same as that of the power converter of the first embodiment according to the present invention, except that the amount of current differs from the path through which the supply current flows.

 FIG. 10 is a circuit block diagram in which the DC current source 2 in FIG. 2 is replaced with a DC voltage source 1 and a DC reactor.

 In Fig. 10, the following circuit constants are used, which agrees with the computer simulation results shown in Fig. 13. The DC voltage source 1 continuously supplies a direct current to the first inductive load 6 and the second inductive load 7 through the DC reactor L dc (hereinafter simply referred to as “supply current”). ) Note that the load voltage is measured at both ends of the inductive load circuit.

<Circuit constants in Fig. 10>

DC voltage source 1 voltage: 1 0 0 V,

Inductance of DC reactor L d c (L d c): l mH,

Capacitance of the first capacitor (C 1): 5 0 0 micro F

Capacitance of the second capacitor (C 2): 5 0 0 micro F,

Inductance of first inductive load 6 (L 1): 50 micro H, equivalent resistance of first inductive load 6 (R 1): 0.0 2 2 ohm,

Inductance of second inductive load 7 (L 2): 50 micro H, equivalent resistance of second inductive load 7 (R 2): 0.0 2 2 ohm,

Switching frequency of reverse conducting semiconductor switch (f sw): 5 0 0 Hz. Next, the operation principle of the power conversion device according to the second embodiment of the present invention will be described with reference to FIG. 13 and FIGS. 15 (A) to 15 (F).

The sections delimited by (a) to (ί) in Fig. 13 correspond to the respective states in Figs. 15 (Α) to 15 (F). FIG. 15 (Α) to FIG. 15 (F) are for explaining the principle of operation, and the control means 4 is not shown. Also, the first inductive load 6 and the second Conductive load 7 shows only the inductance and resistance components. DC current source 2 is composed of DC voltage source 1 and DC reactor L dc, and is the same as FIG. The arrow indicates the current and its direction, and the thickness of the arrow indicates the magnitude of the current. However, the thickness of the arrows is relative.

 As an initial condition, magnetic energy with current is accumulated in the first inductive load 6 and the second inductive load 7 in a state where the first capacitor C 1 and the second capacitor C 2 are not charged. Assuming that

 1) When the control means 4 turns on the first reverse conducting semiconductor switch SW1 and at the same time turns off the second reverse conducting semiconductor switch SW2,

1 Section (a) in Fig. 3 and state in Fig. 15 (A). The second capacitor C2 is charged by the supply current. Furthermore, the current flowing by the magnetic energy of the first inductive load 6 and the second inductive load 7 is interrupted by the second reverse conduction type semiconductor switch SW 2, and as a result, the second capacitor C 2 is connected. Charge.

 2) Eventually, the section shown in Fig. 13 (b) and Fig. 15 (B) is reached. Resonance between the inductance component L 1 of the first inductive load 6 and the inductance component L 2 of the second inductive load L 2 and the resonance of the second inductance C 2 The electric power stored in the second capacitor C 2 is discharged to the first inductive load 6 and the second inductive load 7. When the electric power stored in the second capacitor C 2 is discharged and disappears, the voltage across the second capacitor C 2 becomes approximately 0 [V], and no current flows through the second capacitor C 2.

3) Then, the section (c) in Fig. 13 and the state shown in Fig. 15 (C) are obtained. The current flowing by the magnetic energy stored in the first inductive load 6 and the second inductive load 7 is as shown by the arrow indicating the load current in Fig. 15 (C). Current flows through At this time, load current flows through the self-extinguishing element of the first reverse conducting semiconductor switch SW 1 and the diode of the second reverse conducting semiconductor switch SW 2.

 4) Subsequently, when the control means 4 turns off the first reverse conducting semiconductor switch SW 1 and simultaneously turns on the reverse conducting semiconductor switch SW 2,

1 Section (d) in Fig. 3 and state shown in Fig. 15 (D). The first capacitor C 1 is charged by the supply current. Furthermore, the current flowing by the magnetic energy of the first inductive load 6 and the second inductive load 7 is interrupted by the first reverse conducting semiconductor switch SW 2, and as a result, the first capacitor C 1 is turned off. Charge.

 5) Eventually, the section shown in Fig. 13 (e) and Fig. 15 (E) is reached. The resonance of the inductance component L 1 of the first inductive load 6 and the combined inductance component L 1 + L 2 of the inductance component L 2 of the second inductive load 7 and the first capacitor C 1 The electric power stored in the first capacitor C 1 is discharged to the first inductive load 6 and the second inductive load 7. When the electric power stored in the first capacitor C 1 is discharged and disappears, the voltage across the first capacitor C 1 becomes approximately 0 [V], and no current flows through the first capacitor C 1.

6) Then, the section (f) in Fig. 13 and the state shown in Fig. (F) are obtained. The current flowing by the magnetic energy stored in the first inductive load 6 and the second inductive load 7 flows as shown by the arrow indicating the load current in Fig. 15 (F). At this time, a load current flows through the diode of the first reverse conducting semiconductor switch SW 1 and the self-extinguishing element of the second reverse conducting semiconductor switch SW 2. 7) Subsequently, when the control means 4 turns on the first reverse conducting semiconductor switch SW1 and at the same time turns off the second reverse conducting semiconductor switch SW2, the section shown in FIG. a) The state shown in Fig. 15 (A) is obtained. The power conversion device according to the second embodiment of the present invention can apply the AC oscillating current to the first inductive load 6 and the second inductive load 7 by repeating the above-described operation in a steady state.

 Next, features of the power conversion device according to the second embodiment of the present invention will be described. The power conversion device according to the second embodiment of the present invention can obtain substantially the same AC oscillating current as that of the power conversion device according to the first embodiment of the present invention, based on the operation principle described above.

Further, the capacitance (C 1) of the first capacitor C 1 and the capacitance (C 2) of the second capacitor C 2 are respectively the inductance (L 1) of the first inductive load 6 and Synthesis of inductance (L 2) of second inductive load 7 Resonance with inductance (L 1 + L 2) absorbs and releases the magnetic energy of first inductive load 6 and second inductive load 7 An extremely small capacity is sufficient. In other words, a capacity that only absorbs and releases the magnetic energy of the half cycle of the AC oscillating current supplied to the first inductive load 6 and the second inductive load 7 is sufficient. The first capacitor C 1 and the second capacitor C 2 are a large-capacity smoothing capacitor for stably supplying the DC voltage used in the conventional voltage-type PWM chamber circuit, and its capacitance · The purpose is completely different. Since the first capacitor C 1 and the second capacitor C 2 are alternately charged and discharged, the current duty per capacitor is halved compared to the ME RS resonant inverter circuit. Since the first capacitor C 1 and the second capacitor C 2 always have the same polarity when the capacitor is charged / discharged, polar capacitors can be used. On-off switching frequency of reverse conducting semiconductor switch

(fsw) is the combined inductance (L 1 + L 2) of the inductance (L 1) of the first inductive load 6 and the inductance (L 2) of the second inductive load 7. The first resonant frequency (fres 1, \ / 2% (L 1 + L 2) (C 1)) determined by the capacitance (C 1) of the capacitor C 1 of 1 and the combined inductance component (L 1 + L 2) or the second resonance frequency (fres 2, 1/2 π f (L 1 + L 2) (C 2)), whichever is determined by the capacitance (C 2) of the second capacitor C 2, whichever is lower When the reverse conducting semiconductor switch is turned on by controlling the Z-off state of the reverse conducting semiconductor switch so that the frequency is equal to or lower than this frequency, the self-extinguishing type that constitutes the reverse conducting semiconductor switch When the element is turned off at substantially zero voltage and substantially zero current, the self-extinguishing element constituting the reverse conducting semiconductor switch is a soft switch that is at substantially zero voltage. It can be a bridging operation. As long as this condition is satisfied, the frequency of the AC oscillating current supplied to the first inductive load 6 and the second inductive load 7 can be made variable by controlling the switching frequency of the reverse conducting semiconductor switch. it can.

 The AC oscillation current supplied to the first inductive load 6 and the second inductive load 7 is the resistance component R 1 of the first inductive load 6 and the resistance component R of the second inductive load 7. Energy is consumed by the combined resistance component R 1 + R 2 of 2, and the current is attenuated. The consumed energy is injected by the direct current source 2. That is, since the power supplied from the DC current source 2 only needs to be consumed by the combined resistance component of the first inductive load 6 and the second inductive load 7, the current from the DC current source 2 is Another feature is that the current capacity of the power supply line to the power conversion device according to the second embodiment of the invention can be small.

Further, the power conversion device of the second embodiment according to the present invention has as few as two reverse conducting semiconductor switches. In addition, the first reverse conducting semiconductor switch SW Since the negative electrode side of 1 and the negative electrode side of the second reverse conducting semiconductor switch SW 2 are connected, it is not necessary to insulate the circuits that drive the gates of the respective reverse conducting semiconductor switches from each other. You can also share power.

 In addition, the DC current source 2 is used to obtain the voltage of the AC oscillating current supplied to the first inductive load 6 and the second inductive load 7, and There is also a feature that may be half of the voltage.

 Further, when a field effect transistor or a semiconductor element having an equivalent structure is used as a self-extinguishing element constituting a reverse conducting semiconductor switch, the control means is configured so that the diode becomes conductive in the forward direction. If the self-extinguishing element is controlled to be in a conductive state, a synchronous rectification method can be used to reduce conduction loss.

 [Example 3] 1-capacitor horizontal half-type M ERS resonant inverter circuit FIG. 3 is a circuit block diagram showing a configuration of a power converter according to a third embodiment of the present invention.

More specifically, FIG. 3 shows that the first reverse conducting semiconductor switch SW 1 and the second reverse conducting semiconductor switch SW 2 are connected to the negative side of the first reverse conducting semiconductor switch SW 1 and the second reverse conducting semiconductor switch SW 1. A reverse-conducting semiconductor switch circuit with the negative terminal DCN as the point where the negative electrode side of the conductive semiconductor switch SW 2 is connected, and a capacitor (1) and one end of the capacitor C are connected to the first reverse-type semiconductor switch SW 1 The point connected to the positive side is the first AC terminal AC 1, and the point where the other end of the capacitor C is connected to the positive side of the second reverse conducting semiconductor switch SW 1 is the second AC terminal AC 2. A DC reactor circuit with a positive terminal DCN at the point where the 1-capacitor horizontal half-type MERS circuit, the first DC reactor L dcl and the second DC reactor L dc 2 are connected is connected to the first DC Connect the other end of the reactor L dc 1 to the first AC terminal AC 1 1 capacitor horizontal half bridge circuit 2 1 and 1 capacitor horizontal half type, which are configured by connecting the other end of the second DC reactor L dc 2 to the second AC terminal AC 2 DC voltage source 1 connected between the positive terminal DCP and the negative terminal DCN of the bridge circuit 2 1 and 1 1 side AC terminal AC 1 and 2nd AC terminal AC 2 An inductive load 5 connected between the control means 4 and

 When the first reverse conducting semiconductor switch SW1 is on, the control means 4 turns off the second reverse conducting semiconductor switch SW2 and turns off the first reverse conducting semiconductor switch SW1. In this state, the second reverse conducting semiconductor switch SW2 is turned on, and the first reverse conducting semiconductor switch SW1 and the second reverse conducting semiconductor switch SW2 are not simultaneously turned off. Control the ON / OFF state of the reverse conducting semiconductor switch

 Furthermore, the control means 4 has a resonance frequency (f r e s, \ / 2) determined by the inductance (L) of the inductive load 5 and the capacitance (C) of the capacitor C.

 (L) (C)) When the reverse conducting semiconductor switch is turned on / off by controlling the ON / OFF state of the reverse conducting semiconductor switch with the following switching frequency (fsw), the reverse conducting semiconductor switch The self-extinguishing element that constitutes the switch is characterized by a soft switching operation with substantially zero voltage.

 Next, the operation principle of the power conversion device according to the third embodiment of the present invention will be described with reference to FIG. 16 and FIGS. 17 (A) to 17 (F).

 Figure 16 is the circuit block diagram shown in Figure 30 and shows the results of computer simulation when the following circuit constants are used.

<Circuit constants in Fig. 16>

DC voltage source 1 voltage: 1 0 0 V, 1st DC reactor L dcl inductance (L dcl): 1 mH,

Inductance of second DC reactor L d c 2 (L d c 2): 1 m H,

Capacitor C capacitance (C): 5 0 0 micro F,

Inductive load 5 inductance (L): 1 0 0 micro H

Inductive load 5 equivalent resistance (R): 0.0 4 3 ohm,

Switching frequency of reverse conduction type semiconductor switch (f sw): 5 0 0 Hz.

 More specifically, Fig. 16 shows the current flowing through the inductive load (load current) I load, the voltage applied to the inductive load V 1 oad (equal to the voltage V c across the capacitor C), the first inverse Voltage V swl applied to conductive semiconductor switch SW 1, voltage V sw 2 applied to second reverse conductive semiconductor switch SW 2, current I swl passing through first reverse conductive semiconductor switch SW 1, The current I sw2 passing through the second reverse conducting semiconductor switch SW2, the gate control signal G1 of the first reverse conducting semiconductor switch SW1, and the gate control signal G2 of the second reverse conducting semiconductor switch SW2 The waveform is shown. The current flowing through the inductive load (load current) I l o a d is expressed as positive in the direction flowing from the first AC terminal A C 1 to the second AC terminal A C 2. The DC voltage source 1 continuously supplies a DC current to the inductive load 5 via the first DC reactor L dcl and the second DC reactor L dc 2 (hereinafter simply referred to as “supply current”). ) From (a) of Fig. 16

Each section delimited by (f) corresponds to each state in Fig. 17 (A) to Fig. 17 (F). FIGS. 17 (A) to 17 (F) are for explaining the principle of operation, and the control means 4 is not shown. Inductive load 5 has an inductance component L and a resistance component. Only R is shown. The arrow indicates the current and its direction, and the thickness of the arrow indicates the magnitude of the current. However, the arrow thickness is relative.

 As an initial condition, it is assumed that the magnetic energy of the current is stored in the inductive load 5 while the capacitor C is not charged.

 1) When the control means 4 turns on the first reverse conducting semiconductor switch SW1 and at the same time turns off the second reverse conducting semiconductor switch SW2, the section (a) in FIG. The state shown in Fig. 17 (A) is obtained. Capacitor C is charged by the supply current. Furthermore, the current flowing by the magnetic energy of the inductive load 5 is interrupted by the second reverse conducting semiconductor switch SW 2, and as a result, the capacitor C is charged.

 2) Eventually, the section shown in Fig. 16 (b) and Fig. 17 (B) is reached. Resonance between the inductance component L of the inductive load 5 and the capacitor C discharges the power stored in the capacitor C to the inductive load 5. When the electric power stored in the capacitor C is discharged and lost, the voltage across the capacitor C becomes approximately 0 [V], and no current flows through the capacitor C.

 3) Then, the section (c) in Fig. 16 and the state shown in Fig. 17 (C) are obtained. The current that flows due to the magnetic energy stored in the inductive load 5 flows as shown by the arrow indicating the load current in Fig. 17 (C). At this time, load current flows through the self-extinguishing element of the first reverse conducting semiconductor switch SW 1 and the diode of the second reverse conducting semiconductor switch SW 2.

4) Subsequently, when the control means 4 turns off the first reverse conducting semiconductor switch SW 1 and at the same time turns on the reverse conducting semiconductor switch SW 2, the section (d) in FIG. The state shown in Fig. (D) is obtained. Capacitor C is charged by the supply current. Further, the current flowing by the magnetic energy of the inductive load 5 is interrupted by the first reverse conducting semiconductor switch SW 2, and as a result, the capacitor C is charged. 5) Eventually, the section shown in Fig. 16 (e) and Fig. 17 (E) is reached. Due to the resonance between the inductance component L of the inductive load 5 and the capacitor C, the electric power stored in the capacitor C is discharged to the inductive load 5. When the power stored in the capacitor C is discharged and lost, the voltage across the capacitor C becomes approximately 0 [V], and no current flows through the capacitor C.

 6) Then, the section (f) in Fig. 16 and the state shown in Fig. 17 (F) are obtained. The current that flows due to the magnetic energy stored in the inductive load 5 flows as shown by the arrow indicating the load current in Fig. 17 (F). At this time, a load current flows through the diode of the first reverse conducting semiconductor switch SW1 and the self-extinguishing element of the second reverse conducting semiconductor switch SW2.

 7) Subsequently, when the control means 4 turns on the first reverse conducting semiconductor switch SW 1 and at the same time turns off the second reverse conducting semiconductor switch SW 2, the section shown in FIG. (A) The state shown in Fig. 17 (A) is obtained. The power conversion device according to the first embodiment of the present invention can apply the alternating vibration current to the inductive load 5 by repeating the above-described operation in a steady state.

 Next, features of the power conversion device according to the third embodiment of the present invention will be described. The capacitance (C) of the capacitor C may be a very small capacitance that only absorbs and releases the magnetic energy of the inductive load 5 by resonance with the inductance (L) of the inductive load 5. In other words, a capacity that is sufficient for absorbing and releasing the half-cycle magnetic energy of the AC oscillation current supplied to the inductive load 5 is sufficient. Capacitor C is completely different from the large-capacity smoothing capacitor for stably supplying the DC voltage used in conventional voltage-type PWM inverter circuits.

 On / off switching frequency of reverse conducting semiconductor switch

(fsw) is the inductance (L) of inductive load 5 and capacitor C Resonance frequency determined by capacitance (C) (fres, 1/2 (L)

(C)) When turning the reverse conducting semiconductor switch on and off by controlling the on / off state of the reverse conducting semiconductor switch so that The shape element can be soft-switching with a substantially zero voltage. Within this range of conditions, the frequency of the AC oscillating current supplied to the inductive load 5 can be varied by controlling the switching frequency of the reverse conducting semiconductor switch.

 Also, if the switching frequency (fsw) of the reverse conducting semiconductor switch is less than or equal to the resonance frequency (ires) determined by the inductance (L) of the inductive load 5 and the capacitance (C) of the capacitor C, The current flowing through the conductive semiconductor switch is significantly reduced, and the conduction loss of the reverse conductive semiconductor switch is greatly reduced. While the capacitor C is being charged / discharged, the load current does not pass through the reverse conducting semiconductor switch. During this period, the reverse conduction type semiconductor switch has a current corresponding to the active power consumed by the resistance component R of the inductive load 5 and is supplied from the DC voltage source 1 to the first DC reactor L dc 1 and the second DC. Only the current supplied to the inductive load 5 through the reactor L dc 2 flows. When the voltage across capacitor C is approximately 0 [V], a load current flows through the reverse conducting semiconductor switch. When the switching frequency (fsw) is made lower than the resonant frequency (ires), the period during which the voltage across the capacitor C is approximately 0 [V] increases, and as a result, the load current flows through the reverse conducting semiconductor switch. Will increase. Therefore, the range of change in the frequency of the AC oscillating current supplied to the inductive load 5 is selected according to the purpose / range of control.

Also, the AC oscillating current supplied to the inductive load 5 consumes energy in the resistance component R of the inductive load 5 and the current is attenuated. The consumed energy is injected into the first DC reactor L dc 1 and the second DC reactor. This is performed by the DC voltage source 1 which is “direct current source” via L dc 2. That is, since the electric power supplied from the DC voltage source 1 only needs to be consumed by the resistance component R of the inductive load 5, the power converter of the third embodiment according to the present invention from the DC voltage source 1 There is also a feature that the current capacity of the power supply line to can be reduced.

 Further, the power conversion device of the third embodiment according to the present invention has as few as two reverse conducting semiconductor switches. Also, in order to connect the negative side of the first reverse conducting semiconductor switch SW1 and the negative side of the second reverse conducting semiconductor switch SW2, the circuits that drive the gates of the respective reverse conducting semiconductor switches are insulated from each other. You can share the power supply of the circuit that drives the gate.

 Further, the DC voltage source 1 has a feature that it can be half the voltage of the DC current source 2 of the M E R S resonant inverter circuit in order to obtain the voltage of the AC oscillating current supplied to the inductive load 5.

 [Embodiment 4] Deformation pattern of one-capacitor horizontal half-type M E R S resonant inverter circuit

 FIG. 4 is a circuit block diagram showing the configuration of the power conversion device according to the fourth embodiment of the present invention.

More specifically, FIG. 4 shows that the first reverse conducting semiconductor switch SW 1 and the second reverse conducting semiconductor switch SW 2 are connected to the negative side of the first reverse conducting semiconductor switch SW 1 and the second reverse conducting semiconductor switch SW 1. Conductive semiconductor switch SW 2 Reverse-conducting semiconductor switch circuit with the negative terminal DCN connected to the negative side and capacitor C, one end of capacitor C on the positive side of the first reverse-conducting semiconductor switch SW 1 The point connected to the first AC terminal AC 1 and the other end of the capacitor C connected to the positive side of the second reverse conducting semiconductor switch SW 2 are configured as the second AC terminal AC 2. 1 capacitor horizontal half type ME The inductive load circuit with the positive terminal DCP at the point where the RS circuit and the first inductive load 6 and the second inductive load 7 are connected is connected to the positive side of the first reverse conducting semiconductor switch SW 1. 1 capacitor that is configured by connecting the other end of the first inductive load 6 and connecting the positive side of the second reverse conducting semiconductor switch SW 2 and the other end of the second inductive load 7 A horizontal half-type bridge circuit 2 2, and a DC current source 2 connected between a positive terminal DCP and a negative terminal D CN of a 1-capacitor horizontal half-type bridge circuit 2 2, a control means 4, and a control means 4. When the first reverse conducting semiconductor switch SW 1 is in the on state, the second reverse conducting semiconductor switch SW 2 is in the off state, and the first reverse conducting semiconductor switch SW 1 is in the off state. In this case, the second reverse conduction type semiconductor switch SW2 is turned on and the first reverse conduction type semiconductor switch SW2 is turned on. Controls the state of the conductor switch SW 1 and the second reverse conducting semiconductor Suitsuchi SW 2 is turned off the reverse conducting semiconductor Suitsuchi so as not to state at the same time on Z off,

 Further, the control means 4 has an on / off switching frequency (fsw) of the reverse conducting semiconductor switch so that the inductance (L 1) of the first inductive load 6 and the inductance of the second inductive load 7 (L 2 By controlling the on / off state of the reverse conducting semiconductor switch so that it is less than the resonance frequency (fres) determined by the combined inductance (L 1 + L 2) and the capacitance (C) of the capacitor C, When the reverse conducting semiconductor switch is turned on and off, the self-extinguishing element that constitutes the reverse conducting semiconductor switch is characterized by performing a soft switching operation that is a substantially negative voltage.

The operation of the power converter of the fourth embodiment according to the present invention is the same as that of the power converter of the third embodiment according to the present invention, except that the amount of current differs from the path through which the supply current flows. FIG. 11 is a circuit block diagram in which the DC current source 2 in FIG. 4 is replaced with a DC voltage source 1 and a DC reactor L dc.

 In Fig. 11, when the following circuit constants are used, the computer simulation results shown in Fig. 16 agree. The DC voltage source 1 continuously supplies a direct current to the first inductive load 6 and the second inductive load 7 via the DC reactor L dc (hereinafter simply referred to as “supply current”). ) Note that the load voltage is measured at both ends of the inductive load circuit.

<Circuit constants in Fig. 11>

DC voltage source 1 voltage: 1 0 0 V,

Inductance of DC reactor L d c (L d c): l mH,

Capacitor C capacitance (C): 5 0 0 micro F,

Inductance of first inductive load 6 (L 1): 50 micro H, equivalent resistance of first inductive load 6 (R 1): 0.0 2 2 ohm, inductance of second inductive load 7 (L 2): 50 micro H, equivalent resistance of second inductive load 7 (R 2): 0.0 2 2 ohm,

Switching frequency (i sw) of reverse conducting semiconductor switch: 5 0 0 Hz. Next, the operation principle of the power conversion device according to the fourth embodiment of the present invention will be described with reference to FIGS. 16 and 18 (A) to 18 (F).

Each section divided by (a) to (f) in Fig. 16 corresponds to the respective states in Fig. 18 (A) to Fig. 18 (F). FIG. 18 (A) to FIG. 18 (F) are for explaining the principle of operation, and the control means 4 is not shown. Also, the first inductive load 6 and the second inductive load 7 show only the inductance component and the resistance component, respectively. The DC current source 2 uses a DC voltage source 1 and a DC reactor L dc, and is the same as Fig. 11. Arrows indicate current and direction The thickness of the arrow indicates the magnitude of the current. However, the thickness of the arrows is relative.

 As an initial condition, it is assumed that the magnetic energy of the current is accumulated in the first inductive load 6 and the second inductive load 7 while the capacitor C is not charged.

 1) When the control means 4 turns on the first reverse conducting semiconductor switch SW1 and at the same time turns off the second reverse conducting semiconductor switch SW2, the section (a) in FIG. The state shown in Fig. 18 (A) is obtained. Capacitor C is charged by the supply current. Furthermore, the current flowing due to the magnetic energy of the first inductive load 6 and the second inductive load 7 is interrupted by the second reverse conducting semiconductor switch SW 2 and as a result, the capacitor C is charged. .

 2) Eventually, the section shown in Fig. 16 (b) and Fig. 18 (B) is reached. The inductance component L 1 of the first inductive load 6 and the inductance component L 2 of the second inductive load L 2 are stored in the capacitor C due to the resonance of the combined inductance component L 1 + L 2 and the capacitor C. Electric power is discharged to the first inductive load 6 and the second inductive load 7. When the electric power stored in the capacitor C is discharged and lost, the voltage across the capacitor C becomes approximately 0 [V], and no current flows through the capacitor C.

 3) Then, the section (c) in Fig. 16 and the state shown in Fig. 18 (C) are obtained. The current flowing by the magnetic energy stored in the first inductive load 6 and the second inductive load 7 flows as shown by the arrow indicating the load current in FIG. 18 (C). At this time, a load current flows through the self-extinguishing element of the first reverse conducting semiconductor switch SW1 and the diode of the second reverse conducting semiconductor switch SW2. '

4) Subsequently, when the control means 4 turns off the first reverse conducting semiconductor switch SW 1 and simultaneously turns on the reverse conducting semiconductor switch SW 2, 16 Section (d) in Figure 6 and state shown in Figure 18 (D). Capacitor C is charged by the supply current. Furthermore, the current flowing by the magnetic energy of the first inductive load 6 and the second inductive load 7 is interrupted by the first reverse conducting semiconductor switch SW 2, and as a result, the capacitor C is charged.

 5) Eventually, the section shown in Fig. 16 (e) and Fig. 18 (E) is reached. The inductance component L 1 of the first inductive load 6 and the inductance component L 2 of the second inductive load 7 are stored in the capacitor C due to the resonance of the combined inductance component L 1 + L 2 of the L 2 and the capacitor C. Electric power is discharged to the first inductive load 6 and the second inductive load 7. When the power stored in capacitor C is discharged and lost, the voltage across capacitor C is approximately 0.

 [V] and no current flows through the capacitor C.

 6) Then, the section (f) in Fig. 16 and the state shown in Fig. 18 (F) are obtained. The current flowing by the magnetic energy stored in the first inductive load 6 and the second inductive load 7 flows as shown by the arrow indicating the load current in FIG. 18 (F). At this time, a load current flows through the diode of the first reverse conducting semiconductor switch SW1 and the self-extinguishing element of the second reverse conducting semiconductor switch SW2.

 7) Subsequently, when the control means 4 turns on the first reverse conducting semiconductor switch SW 1 and at the same time turns off the second reverse conducting semiconductor switch SW 2, the section shown in FIG. (A) The state shown in Fig. 18 (A) is obtained. The power conversion device according to the fourth embodiment of the present invention can repeat the above-described operation in a steady state, and can provide an AC oscillating current to the first inductive load 6 and the second inductive load 7.

Next, features of the power conversion device according to the fourth embodiment of the present invention will be described. The power converter of the fourth embodiment according to the present invention is based on the above operating principle. Almost the same AC oscillating current as that of the power conversion device according to the third embodiment of the present invention can be obtained.

 The capacitance (C) of the capacitor C is the combined inductance of the inductance (L 1) of the first inductive load 6 and the inductance (L 2) of the second inductive load 7. An extremely small capacity is sufficient to absorb and release the magnetic energy of the first inductive load 6 and the second inductive load 7 by resonance with (L 1 + L 2). In other words, the capacity may be sufficient to absorb and release half the magnetic energy of the AC oscillating current supplied to the first inductive load 6 and the second inductive load 7. Capacitor C is completely different in capacity and purpose from the large-capacity smoothing capacitor that stably supplies the DC voltage used in the conventional voltage-type PWM inverter circuit.

 On / off switching frequency of reverse conducting semiconductor switch

(fsw) is the resonance frequency determined by the inductance (L 1) of the first inductive load 6, the combined inductance (L 1 + L 2) of the second inductive load 7, and the capacitance (C) of the capacitor C (Ires, 1/2 (L 1 + L

2) (C)) When the reverse conducting semiconductor switch is turned on and off by controlling the on / off state of the reverse conducting semiconductor switch so that The arc extinguishing element can be configured to perform a soft switching operation with substantially zero voltage. Within this range of conditions, the frequency of the AC oscillating current supplied to the first inductive load 6 and the second inductive load 7 can be made variable by controlling the switching frequency of the reverse conducting semiconductor switch. .

In addition, the switching frequency (: f SW) of the reverse conducting semiconductor switch is set to the combined inductance of the inductance (L 1) of the first inductive load 6 and the inductance (L 2) of the second inductive load 7 ( L 1 + L 2) and the resonance frequency (ires) determined by the capacitance (C) of the capacitor C, and If it is in the vicinity, the current flowing through the reverse conducting semiconductor switch will be greatly reduced, and the conducting loss of the reverse conducting semiconductor switch will be greatly reduced. Capacitor

During the period when C is being charged and discharged, the load current does not pass through the reverse conducting semiconductor switch. During this period, the reverse-conducting semiconductor switch is effectively consumed by the combined resistance component R 1 + R 2 of the resistance component R 1 of the first inductive load 6 and the resistance component R 2 of the second inductive load 7. Only the current supplied from the DC current source 2 to the first inductive load 6 and the second inductive load 7 flows at a current equivalent to electric power. When the voltage across capacitor C is approximately 0 [V], the load current flows through the reverse conducting semiconductor switch. When the switching frequency (fsw) is made lower than the resonant frequency (; fres), the period during which the voltage across the capacitor C is approximately 0 [V] increases, and as a result, the load current flows to the reverse conducting semiconductor switch. The flowing time increases. Therefore, the frequency change range of the AC oscillating current supplied to the first inductive load 6 and the second inductive load 7 is selected according to the purpose and range of control.

 In addition, the AC oscillation current supplied to the first inductive load 6 and the second inductive load 7 is the resistance component R 1 of the first inductive load 6 and the resistance component R of the second inductive load Ί. Energy is consumed by the combined resistance component R 1 + R 2 of 2, and the current is attenuated. The consumed energy is injected by the direct current source 2. That is, since the power supplied from the DC current source 2 only needs to be consumed by the combined resistance component of the first inductive load 6 and the second inductive load 7, the current from the DC current source 2 is There is also a feature that the current capacity of the feeder line to the power converter of the fourth embodiment according to the invention can be small.

In addition, the power converter of the fourth embodiment according to the present invention has as few as two reverse conducting semiconductor switches. Also, since the negative electrode side of the first reverse conducting semiconductor switch SW 1 and the negative electrode side of the second reverse conducting semiconductor switch SW 2 are connected, the circuits that drive the gates of the respective reverse conducting semiconductor switches SW 2 It is possible to share the power supply of the circuit that drives the gate.

 Furthermore, the DC current source 2 obtains the voltage of the AC oscillating current to be supplied to the first inductive load 6 and the second inductive load 7 by half the voltage of the DC current source 2 of the ME RS resonant inverter circuit. There are also good features.

 [Example 5] Confirmation of variable frequency

 FIG. 19 is a diagram showing computer simulation results of the configurations of the power conversion device of the first embodiment and the power conversion device of the second embodiment according to the present invention. FIG. 20 is a diagram showing a computer simulation result of the configuration of the power conversion device of the third embodiment and the power conversion device of the fourth embodiment according to the present invention.

 More specifically, FIG. 19 shows the case where the switching frequency (fsw) of the reverse conducting semiconductor switch is set to 200 Hz in the circuit constants of FIG. 13 and the contents shown in FIG. 1 Same as Figure 3. Similarly, FIG. 20 shows the case where the switching frequency (fsw) of the reverse conducting semiconductor switch is 2 0 00 Hz in the circuit constants of FIG. 16, and the contents shown in FIG. Same as Figure 6.

 From FIG. 19 and FIG. 20, the power converter of the first embodiment according to the present invention to the power converter of the fourth embodiment according to the present invention supplies alternating frequency alternating current. It is possible to confirm that soft switching operation is performed with approximately zero current when turning on the reverse conducting semiconductor switch and approximately zero voltage when turning off.

 [Example 6] Circuit configuration with common positive electrode side (Part 1)

FIG. 5 and FIG. 6 are circuit block diagrams showing the configurations of the power conversion devices of the fifth and sixth embodiments according to the present invention. More specifically, FIGS. 5 and 6 show that in each of the power converters of the first and second embodiments according to the present invention, the connection polarity of the DC voltage source 1 or the DC current source 2 is reversed, In this configuration, the connection polarity of the first reverse conducting semiconductor switch SW 1 and the second reverse conducting semiconductor switch SW 2 is reversed.

 Further, when the first capacitor C 1 and the second capacitor C 2 are polar capacitors, the connection polarity is reversed. The positive terminal DCP is the point where the positive side of the first reverse conducting semiconductor switch SW1 and the positive side of the second reverse conducting semiconductor switch SW2 are connected, and the positive side is common. The power conversion device of the fifth embodiment according to the present invention includes the power conversion device of the first embodiment according to the present invention and the power conversion device of the sixth embodiment according to the present invention. It has the same functions, actions, and effects as the second power converter.

 The same configuration can be used when a reverse-conducting semiconductor switch uses a P-channel power MOS FET, or an anti-parallel connection circuit of a transistor and a diode.

 [Example 7] Circuit configuration with common positive electrode side (Part 2)

 FIGS. 7 and 8 are circuit block diagrams showing the configurations of the power conversion devices according to the seventh and eighth embodiments of the present invention.

More specifically, FIGS. 7 and 8 show that in each of the power converters of the third and fourth embodiments according to the present invention, the connection polarity of the DC voltage source 1 or the DC current source 2 is reversed, In this configuration, the connection polarity of the first reverse conducting semiconductor switch SW 1 and the second reverse conducting semiconductor switch SW 2 is reversed. The point where the positive electrode side of the first reverse conducting semiconductor switch SW1 and the positive electrode side of the second reverse conducting semiconductor switch SW2 are connected is the positive terminal DC が あ る, and the positive electrode side is common. The power conversion device according to the seventh embodiment of the present invention is related to the power conversion device according to the third embodiment of the present invention and the present invention. The power converter of the eighth embodiment has the same functions, operations, and effects as the fourth power converter according to the present invention. .

 The same configuration can be used when using a reverse channel semiconductor switch with P-channel power M O S F E T, 逆 Ν 逆 transistor and diode parallel connection circuit.

 [Embodiment 8] Inductive load with tap / inductive load without tap FIG. 9 is a circuit block diagram showing the configuration of the power converter of the ninth embodiment according to the present invention.

 More specifically, FIG. 9 shows that the first inductive load 6 and the second inductive load 7 of the power conversion device according to the second embodiment of the present invention are replaced with a tapped inductive load 8. The tap is the positive terminal DC Ρ and the DC current source 2 is connected. It has the same function, operation, and effect as the second power converter according to the present invention.

 The same applies when the first inductive load 6 and the second inductive load 7 of the power conversion device according to the fourth embodiment of the present invention are replaced with a tapped inductive load 8.

 In the case of an inductive load without a tap (not shown), an inductive load (not shown) without a tap to be supplied with AC vibration current using a tapped coupling transformer (not shown) is used. You may be allowed to match with

 [Example 9] Another configuration of DC current source (Part 1)

 FIG. 10 and FIG. 11 are circuit block diagrams showing the configurations of the power converters according to the 10th and 11th embodiments of the present invention.

More specifically, FIG. 10 and FIG. 11 show that the DC current source 2 is connected to the DC voltage in each of the power converters of the second and fourth embodiments according to the present invention. The source 1 and the DC reactor L dc connected to the DC voltage source 1 are replaced.

 In order to create the DC current source 2 from the DC voltage source 1, it is necessary to increase the impedance to make it a current source, and this can be handled by connecting via the DC reactor Ldc.

 [Example 10] Another configuration of DC current source (Part 2)

 FIG. 12 (A) is a circuit block diagram showing another configuration of the DC current source 2 in each of the power conversion devices of the second and fourth embodiments according to the present invention.

 More specifically, FIG. 12 (A) shows a direct current source 2, an alternating current power source 3, a rectifier circuit RB, and the like in each of the power converters of the second and fourth embodiments according to the present invention. It is replaced with the AC reactor L ac connected between the AC power supply 3 and the AC terminal of the rectifier circuit RB.

 The AC power source 3 is converted into a current source by the AC reactor L a c and is converted to DC by the rectifier circuit R B.

 [Example 1 1] Another configuration of DC current source (Part 3)

 FIG. 12 (B) is a circuit block diagram showing still another configuration of the DC current source 2 in each of the power conversion devices of the second and fourth embodiments according to the present invention.

More specifically, FIG. 12 (B) shows a DC current source 2, an AC power source 3, and an AC power source device at one end in each of the power converters of the second and fourth embodiments according to the present invention. AC power conditioner T h connected to 3 thyristor AC power conditioner on the primary side 高 High impedance transformer HIT r connected to the other end of 1Ί, and AC terminal is high impedance transformer HIT It is replaced with a rectifier circuit RB connected to the secondary side of r. Furthermore, the control means 4 can send a control signal to the thyris AC power adjusting device Th to adjust the amount of AC oscillating current supplied to the inductive load.

 [Example 1 2] Another configuration of DC voltage source

 FIG. 12 (D) is a circuit block diagram showing another configuration of the DC voltage source 1 according to the present invention.

 More specifically, DC voltage source 1 (Fig. 12 (C)) is replaced with rectifier circuit RB and AC power supply 3 connected between AC terminals of rectifier circuit RB (Fig. 12 (D) ).

 In order to create the DC current source 2 from another configuration of the DC voltage source 1 according to the present invention, it can be handled by connecting the DC reactor L dc to the positive terminal of the rectifier circuit RB. '

 Further, in the power converters of the sixth and eighth embodiments according to the present invention, the DC reactor L dc is connected to the negative terminal of the rectifier circuit RB.

 [Example 1 3] Variable frequency induction heating power supply

 When the above-described power conversion device according to the present invention and an induction coil for induction heating of an object to be heated are used as an inductive load, an AC oscillation current supplied to the induction coil according to the object and purpose of the object to be heated It is possible to provide a power supply apparatus for induction heating that can vary the frequency of the power supply.

The power conversion device according to the present invention described above has only two reverse conducting semiconductor switches. It is also characterized by low switching loss due to soft switching operation. This is advantageous when using a high frequency of several Ι Ο Κ ζ ζ or higher. In an induction heating power supply device for home use that requires a high frequency of 30 KHz or more to heat an aluminum pan by induction heating, an air cooling fan is required due to the radiation of the switching element. Pertaining to If an induction heating power supply using a power converter is used, a fanless design is expected to be possible.

 In addition, since the AC oscillating current applied to the induction coil is variable, it is expected that materials with different frequencies for induction heating, such as iron, copper, and aluminum, can be heated in a single circuit. . This is a problem that has been difficult to solve with an induction heating power supply using a conventional inverter having a separate resonant capacitor.

Claims

The scope of the claims 1 A power conversion device that converts DC power into AC power, the power conversion device comprising:  A circuit in which a self-extinguishing element and a diode are connected to a positive electrode side of the self-extinguishing element and a negative electrode side of the diode, and a negative electrode side of the self-extinguishing element and a positive electrode side of the diode are connected, or The equivalent semiconductor element is a reverse conduction type semiconductor switch (hereinafter simply referred to as “reverse conduction type semiconductor switch”), and the first capacitor short circuit is formed by connecting the first reverse conduction type semiconductor switch and the first capacitor in parallel. A self-extinguishing type comprising the first reverse-conducting semiconductor switch, and a second capacitor short circuit comprising a circuit and the second reverse-conducting semiconductor switch and the second capacitor connected in parallel. Two capacitors with the negative electrode terminal at the point where the negative electrode side of the element (hereinafter simply referred to as “the negative electrode side of the reverse conducting semiconductor switch”) and the negative electrode side of the second reverse conducting semiconductor switch are connected A self-conducting semiconductor switch constituting the first reverse conducting semiconductor switch includes a horizontal half-type MERS circuit, and a DC reactor circuit having a positive terminal at a point where the first DC reactor and the second DC reactor are connected. The point at which the positive electrode side of the arc-extinguishing element (hereinafter simply referred to as “the positive electrode side of the reverse conducting semiconductor switch”) and the other end of the first DC reactor are connected is defined as the first AC terminal, and A two-capacitor horizontal half-type ply circuit configured as a second AC terminal at a point where the positive electrode side of the second reverse conducting semiconductor switch and the other end of the second DC reactor are connected;  A DC voltage source connected between the positive terminal and the negative terminal of the two-capacitor horizontal half-type bridge circuit;  An inductive load connected between the first AC terminal and the second AC terminal of the two-capacitor horizontal half-ply circuit; 55 Corrected is paper (m ^ i) A control means, and  When the self-extinguishing element constituting the first reverse conducting semiconductor switch is in a conducting state (hereinafter simply referred to as “a reverse conducting semiconductor switch is in an on state”), the control means The self-extinguishing element constituting the reverse conducting semiconductor switch is set to a blocking state (hereinafter simply referred to as “the reverse conducting semiconductor switch is turned off”), and the first reverse conducting semiconductor switch is turned off. In the state, the second reverse conducting semiconductor switch is turned on so that the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are not turned on at the same time. Controls the on-off state of the reverse conducting semiconductor switch,  Furthermore, the control means includes The switching frequency of on-off of the reverse conducting semiconductor switch is a first resonant frequency determined by the inductance of the inductive load and the capacitance of the first capacitor, and the inductance of the inductive load And the second resonance frequency determined by the capacitance of the second capacitor, whichever is lower, by controlling the on / off state of the reverse conducting semiconductor switch, When the conductive semiconductor switch is turned on, the self-extinguishing element constituting the reverse conductive semiconductor switch has a substantially zero voltage and a substantially zero current, and when the conductive semiconductor switch is turned off, the reverse conductive semiconductor switch The power extinguishing device according to claim 1, wherein the self-extinguishing element performs a soft switching operation of substantially zero voltage. 2 First capacitor short circuit with first reverse conducting semiconductor switch and first capacitor connected in parallel; second capacitor with second reverse conducting semiconductor switch and second capacitor connected in parallel A short circuit is connected between the negative side of the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch. 2-capacitor horizontal half-shaped ME • RS circuit with the negative electrode side connected as the negative electrode terminal, and the inductivity with the positive electrode terminal connected to the first inductive load and the second inductive load The load circuit is a point where the positive electrode side of the first reverse conducting semiconductor switch and the other end of the first inductive load are connected as a first AC terminal, and the second reverse conducting semiconductor A 2-capacitor horizontal half-type bridge circuit configured as a second AC terminal by connecting the positive electrode side of the switch and the other end of the second inductive load;  A direct current source connected between the positive terminal and the negative terminal of the two-capacitor horizontal eight-ridge circuit;  A control means, and When the first reverse conducting semiconductor switch is in an on state, the control means sets the second reverse conducting semiconductor switch in an off state, and the first reverse conducting semiconductor switch is in an off state. In this case, the second reverse conducting semiconductor switch is turned on so that the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are not turned on at the same time. The on-Z-off state of the reverse conducting semiconductor switch is controlled, and the control means is further characterized in that the switching frequency of the reverse conducting semiconductor switch on Z-off is the inductance of the first inductive load. A first resonance frequency determined by a combined inductance of the inductance of the second inductive load and a capacitance of the first capacitor; the combined inductance and the second capacitor; By controlling the ON / OFF state of the reverse conducting semiconductor switch so as to be lower than the lower one of the second resonance frequencies determined by the capacitance of the reverse conducting semiconductor switch, When turning on, the self-extinguishing element constituting the reverse conducting semiconductor switch is at substantially zero voltage and substantially zero current. The power converter according to claim 1, wherein the self-extinguishing element constituting the reverse conducting semiconductor switch performs a soft switching operation at substantially zero voltage. 3 When a field-effect transistor or a semiconductor element having an equivalent structure is used as the self-extinguishing element constituting the reverse conducting semiconductor switch,  The control means according to claim 1 or 2, wherein the control means controls the self-extinguishing element to be in a conductive state when the diode is in a conductive state in a forward direction. The power converter described. 4 The first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are connected to the negative side of the first reverse conducting semiconductor switch and the negative side of the second reverse conducting semiconductor switch. A reverse conducting semiconductor switch leg having a negative electrode terminal; a capacitor; and a point where one end of the capacitor is connected to the positive electrode side of the first reverse conducting semiconductor switch as a first AC terminal; and the capacitor 1 capacitor side-half type MERS circuit configured as a second AC terminal, the point where the other end of the second reverse conduction type semiconductor switch is connected to the positive electrode side, the first DC reactor and the second A DC reactor circuit having a positive electrode terminal at a point where the DC reactor is connected, the other end of the first DC reactor is connected to the first AC terminal, and the second DC reactor is connected. The other end of the second 1 capacitor lateral half-type bridge circuit connected to the current terminal,  A DC voltage source connected between the positive terminal and the negative terminal of the one-capacitor horizontal half-ply circuit; 58 Corrected Akatsuki (Fine 1191) An inductive load connected between the first AC terminal and the second AC terminal of the one-capacitor horizontal half-type bridge circuit;  A control means, and  When the first reverse conducting semiconductor switch is in an on state, the control means sets the second reverse conducting semiconductor switch in an off state, and the first reverse conducting semiconductor switch is in an off state. In this case, the second reverse conducting semiconductor switch is turned on so that the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are not turned off at the same time. The on-off state of the reverse-conducting semiconductor switch is controlled, and the control means further includes an on-Z-off switching frequency of the reverse-conducting semiconductor switch, wherein the inductive load inductance and the capacitor are The reverse conducting semiconductor switch is turned on / off by controlling the ON / OFF state of the reverse conducting semiconductor switch so that the resonance frequency is less than or equal to the resonance frequency determined by the capacitance of the reverse conducting semiconductor switch. The self-extinguishing element constituting the reverse conducting semiconductor switch performs a soft switching operation of substantially zero voltage. 5 The first reverse conduction type semiconductor switch and the second reverse conduction type semiconductor switch are connected to the negative side of the first reverse conduction type semiconductor switch and the negative side of the second reverse conduction type semiconductor switch. A reverse conducting semiconductor switch leg having a negative electrode terminal; a capacitor; and a point where one end of the capacitor is connected to the positive electrode side of the first reverse conducting semiconductor switch as a first AC terminal; and the capacitor 1 capacitor lateral half type MERS circuit configured as a second AC terminal, the point where the other end of the second reverse conduction type semiconductor switch is connected to the positive electrode side, the first inductive load and the second induction An inductive load circuit having a positive electrode terminal at a point where an inductive load is connected is connected to the first reverse conduction type semiconductor switch. And the other end of the first inductive load, and the other end of the second inductive load is connected to the other end of the second inductive load. 1 capacitor horizontal half-type bridge circuit,  A direct current source connected between a positive terminal and a negative terminal of the one-capacitor horizontal half-type ply circuit;  A control means, and  When the first reverse conducting semiconductor switch is in an on state, the control means sets the second reverse conducting semiconductor switch in an off state, and the first reverse conducting semiconductor switch is in an off state. In this case, the second reverse conducting semiconductor switch is turned on so that the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch are not turned off at the same time. The control means controls the on-Z-off state of the reverse conducting semiconductor switch, and the control means determines whether the switching frequency of the reverse conducting semiconductor switch on-Z off is equal to the inductance of the first inductive load. The on / off state of the reverse conducting semiconductor switch so that the resonance frequency is determined by the combined inductance of the inductance of the second inductive load and the capacitance of the capacitor. When the reverse conducting semiconductor switch is turned on / off by controlling the self-extinguishing type semiconductor switch, the self-extinguishing element constituting the reverse conducting semiconductor switch performs a soft switching operation of substantially zero voltage. A power converter. 6. The power converter according to claim 1, wherein a polar capacitor is used for the first capacitor and the second capacitor of the power converter. 7 Reverse the connection polarity of the DC voltage source of the power converter, The connection polarity between the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch is reversed,  Furthermore, when the said 1st capacitor | condenser and the said 2nd capacitor | condenser are polar capacitors, each connection polarity was reversed, Claim 1 or 4 characterized by the above-mentioned. Power converter. 8 Reverse the connection polarity of the DC current source of the power converter, The connection polarity between the first reverse conducting semiconductor switch and the second reverse conducting semiconductor switch is reversed,  Furthermore, when said 1st capacitor | condenser and said 2nd capacitor | condenser are polar capacitors, each connection polarity was reversed, Claim 2 or 5 characterized by the above-mentioned. Power converter. 9 In place of the inductive load circuit having a positive terminal at the point where the first inductive load and the second inductive load of the power converter are connected, Any one of claims 2, 5, 6, or 8 characterized in that it is replaced with an inductive load having a step and one tap is used as a positive terminal. The power converter device described in 1. 1 0 Instead of the inductive load circuit having a positive terminal at the point where the first inductive load and the second inductive load of the power converter are connected, a tapped coupling transformer is used. Any one of claims 2, 5, 6, or 8 characterized in that the tap is a positive terminal and matching is performed with an inductive load having no tapping. The power conversion device according to item 1. 1 1 In place of the DC current source of the power converter, The DC voltage source; A DC reactor connected to the DC voltage source; The power conversion device according to any one of claims 2, 5, 6, 8, 9, and 10, wherein the power conversion device is replaced by 1 2 In place of the DC current source of the power converter, AC power supply, A rectifier circuit; An AC reactor connected between the AC power source and the AC terminal of the rectifier circuit; The power conversion device according to any one of claims 2, 5, 6, 8, 9, and 10, wherein the power conversion device is replaced by 1 3 In place of the DC current source of the power converter, The AC power source; and A Siris evening AC power adjustment device having one end connected to the AC power source; A high-impedance amplifier whose primary side is connected to the other end of the AC power regulator. —Dance transformer, The AC terminal is replaced with the rectifier circuit connected to the secondary side of the high impedance transformer, and Further, the control means sends a control signal to the thyristor AC power adjustment device to adjust the amount of AC oscillating current supplied to the inductive load. The power conversion device according to any one of items 5, 6, 8, 9, or 10. 1 4 In place of the DC voltage source of the power converter, The rectifier circuit; The AC power source connected between the AC terminals of the rectifier circuit; The power conversion device according to any one of claims 1, 4, 6, 7, or 11, wherein the power conversion device is replaced by 1 5 As the inductive load of the power conversion device according to any one of claims 1 to 14, Induction heating characterized by using an induction coil for induction heating of an object to be heated, and varying the frequency of the alternating vibration current supplied to the induction coil according to the object and purpose of the object to be heated. Power supply. 1 6 the induction coil for induction heating the object to be heated; An induction heating characterized in that the induction heating power supply device according to claim 15 is provided, and the induction heating is performed by supplying an alternating vibration current to the induction coil from the induction heating power supply device. apparatus.