CN201142658Y - Motor drives for washing and drying machines - Google Patents

Abstract

In the motor driving device of the washing and drying machine, the first, second, and third inverter circuits respectively drive the compressor motor of the heat pump, the rotating drum driving motor, and the blower fan motor. A plurality of inverter circuits are arranged in parallel between the positive and negative DC power bus bars, and the control circuit is arranged near the inverter circuits.

Description

Motor drives for washing and drying machines

technical field

The utility model relates to a motor drive device for a heat pump type washing and drying machine and the like which utilizes multiple inverter circuits to simultaneously drive multiple motors.

Background technique

As an example of such a motor drive device, Japanese Patent Application Laid-Open No. 2006-116066 discloses a washing and drying machine in which a rotary drum motor is driven by a first inverter circuit and a compressor motor of a heat pump is driven by a second inverter circuit. .

In such a motor driving device, since a plurality of inverter circuits share a DC power supply, the current detection circuit of each inverter circuit will be affected by the current of other inverter circuits and switching noise. As a result, there is a problem that the detection accuracy of the inverter current decreases.

Contents of the invention

The motor driving device of the present utility model comprises: positive and negative DC power supply busbars for supplying DC power, a plurality of inverter circuits for driving the motor, shunt resistors connected to terminals on each negative voltage side of the plurality of inverter circuits, and A control circuit that controls multiple inverter circuits. A plurality of inverter circuits are arranged in parallel between the positive and negative DC power bus bars. Furthermore, the processor of the control circuit is arranged near the inverter circuit.

The motor driving device of the present utility model comprises: a DC power supply; positive and negative DC power supply busbars that supply DC power from the above-mentioned DC power supply; convert the DC power of the above-mentioned DC power supply into AC power, and drive the compressor motor of the heat pump, rotating The first, second, and third inverter circuits of the drum motor and the blower fan motor; a plurality of current detection circuits connected to the plurality of inverter circuits; and a control circuit for controlling the plurality of inverter circuits, wherein the above-mentioned A plurality of inverter circuits are arranged in parallel between the positive and negative DC power bus bars.

With the above configuration, the influence of the general impedance of the DC power supply and the influence of switching noise are reduced, thereby preventing the detection accuracy of the inverter current from deteriorating.

Description of drawings

FIG. 1 is a block diagram of a motor drive device according to Embodiment 1 of the present invention.

FIG. 2 is a circuit diagram of an inverter circuit of the motor drive device.

FIG. 3 is a circuit diagram of a current signal amplifier circuit of the motor drive device.

4 is a timing chart of carrier signal, PWM control signal, and current detection A/D conversion of the control unit of the motor drive device.

FIG. 5 is a block diagram in which an overcurrent detection circuit is added to the current detection circuit of the motor drive device.

FIG. 6 is a circuit diagram of an overcurrent detection circuit of the motor drive device.

7 is a layout diagram of a power supply unit, a current detection unit, and a processor on a control board of the motor drive device.

8 is a block diagram of a processor of a motor drive device according to Embodiment 2 of the present invention.

9 is a layout diagram of a power supply unit, a current detection unit, and a processor on a control board of the motor drive device.

10 is a configuration diagram of a processor of a motor drive device according to Embodiment 3 of the present invention.

11 is a layout diagram of a power supply unit, a current detection unit, and a processor on a control board of the motor drive device.

Detailed ways

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)

Fig. 1 is a block diagram of a motor drive device for a washing and drying machine according to a first embodiment of the present invention.

In Fig. 1, from AC power supply 1 to the rectification circuit that is made up of full-wave rectification circuit 20 and electrolytic capacitor 21, apply AC power to form DC power supply 2 converted into DC power, from DC power supply 2 positive and negative DC power bus 2A, 2B supplies DC power, and converts DC power into three-phase AC power through the first, second and third inverter circuits 3A, 3B and 3C, and simultaneously drives the compressor motor 4A of the heat pump, the rotating drum driving motor 4B and the blower fan Motor 4C. The motors 4A, 4B are detected by the first, second, and third current detection circuits 5A, 5B, 5C and the control circuit 6 connected to the emitter terminals of the switching transistors of the lower arms of the respective inverter circuits to detect the motor currents. , 4C each motor current and sensorless vector control, vector control or sensorless sine wave drive.

The first inverter circuit 3A drives the motor 4A, and the refrigerant is sent from the condenser 7 to the evaporator 8 for heat exchange. The second inverter circuit 3B drives the motor 4B to rotate and drive the rotating drum 9 for washing or drying clothes. The inverter circuit 3C drives the motor 4C to rotate the blower fan 10 , and sends warm air from the condenser 7 into the rotary drum 9 to dry the clothes in the rotary drum 9 . The high-temperature and high-humidity exhaust air from the rotary drum 9 passes through the evaporator 8 for dehumidification and heat exchange, and returns to the suction side of the blower fan 10 .

The control circuit 6 drives the inverter circuit 3B by the position signal from the rotor position detection circuit 40b of the rotary drum drive motor 4B and the motor current signal detected by the current detection circuit 5B and vector controls the rotary drum drive motor 4B, and passes the current detection circuit 5A and 5C detect the respective motor currents of heat pump compressor motor 4A and blower fan motor 4C, respectively control inverter circuits 3A and 3C, and perform sensorless sine-wave drive for low-noise, high-efficiency operation.

The control circuit 6 is made of at least one high-speed processor with a built-in multiple PWM control circuit (not shown) and a high-speed A/D conversion circuit (not shown) for PWM control of the inverter circuits 3A, 3B, and 3C. The inverter circuits 3A, 3B, and 3C are driven by sine waves to control the compressor motor 4A, the rotary drum drive motor 4B, and the blower fan motor 4C at different rotational speeds.

The first inverter circuit 3A carries out sensorless vector control to the compressor motor 4A, detects the motor current of the compressor motor 4A by the first current detection circuit 5A, and performs sensorless sine wave drive, compares the motor current stored in the control circuit 6 The motor parameters and the voltage applied to the motor are used to calculate the current and detected current to estimate the rotor position, correct the virtual d-q axis in the control program, and perform rotor phase control. Due to the structure of the compressor motor 4A, the mechanical rotor position and torque fluctuate due to the structure of the compression mechanism. Therefore, it is necessary to perform position estimation and calculation as accurate as possible. In timing control (field weakening control), the accuracy of position estimation calculation becomes a problem, and therefore, ensuring the accuracy of current detection, ensuring the accuracy of motor parameters, and the position estimation algorithm become issues.

The second inverter circuit 3B carries out vector control to the rotary drum drive motor 4B, detects the position of the permanent magnet of the rotor by the position detection circuit 40b, detects the motor current of the rotary drum drive motor 4B by the second current detection circuit 5B, and converts the coordinates (d-q ) is converted into a vector in the q-axis direction at right angles to the d-axis direction of the permanent magnet of the rotor, and vector control is performed on the rotary drum drive motor 4B.

In addition, when the rotary drum driving motor 4B is a surface magnet motor, it may be driven by a sine wave by open-loop vector control without current detection, and the current value may be obtained by calculation for control. Since the torque current Iq and the d-axis current Id are obtained instantaneously by vector control of the rotary drum drive motor 4B or vector calculation of the motor current, the instantaneous torque can be detected and the load state or unbalanced state of the rotary drum 7 can be determined. Moreover, the timing of timing control can be accurately controlled based on current detection during high-speed dehydration operation.

The third inverter circuit 3C performs position sensorless sine wave drive on the blower fan motor 4C through the constant value control of the reactive current, the sine wave current flows through the blower fan motor 4C, and the integral control stabilizes the reactive current of the voltage applied to the motor control. If the rotational speed of the permanent magnet synchronous motor keeps the driving frequency f constant, the rotational speed of the blower fan motor 4C is constant regardless of the fluctuation of the power supply voltage or the fluctuation of the load. Therefore, if the reactive current constant value control is performed, the driving frequency can be adjusted. Fixed value control, so that the variation of the number of revolutions can be almost zero. In the case of carrying out the open-loop driving frequency constant value control (V/f control mode) such as the reactive current constant value control to the blower fan motor 4C, it is possible to drive the blower fan 10 without being affected by the fluctuation of the DC power supply voltage. Since the rotation speed of the blower fan motor 4C is constant, the fan noise of the blower fan 10 does not change, and it is possible to eliminate harsh fan noise fluctuations caused by changes in the rotation speed.

As described in detail later, the current detection circuits 5A, 5B, and 5C adopt a three-shunt current detection method, which is composed of three or two shunt resistors and a current signal amplification circuit. The basic structures of the current detection circuits 5A, 5B, and 5C are exactly the same , by making the carrier frequencies of all the inverter circuits an integer multiple, the carrier signals are synchronized, and the switching noises during current detection can be prevented from interfering with each other.

Since the output of the compressor motor 4A is 600 to 750W, the number of rotations is 1000 to 6500r/m, and the maximum output current is 3 to 5Arms; the output of the rotary drum drive motor 4B is 50 to 500W, the number of rotations is 30 to 1600r/m, and the maximum output The current is 5 to 8Arms; the output of the fan motor 4C is 30 to 150W, the number of rotations is 4000 to 6000r/m, and the maximum output current is 0.5 to 1.5Arms, so the output of the inverter circuit is the inverter circuit 3A, 3B, 3C Order. If the rotary drum drive motor 4B rotates at a low speed for washing or drying, the motor output is very small, about 50W, and if it is dehydrating at a high speed, it becomes the maximum output of 250 to 500W, but the operation time is shorter than other strokes.

However, since the output of the compressor motor 4A for driving the heat pump is large and the operation time is very long, several hours, a problem of temperature rise occurs. In particular, heat generation and heat dissipation of shunt resistors, wiring patterns, and power semiconductors have become issues. In addition, since the switching noise of the inverter circuit is large, in order to reduce the radiated noise, it is necessary to reduce the ring area through which the current of the inverter circuit flows as much as possible to reduce the generation of electromagnetic fields.

The control circuit 6 is composed of a microcomputer or a digital signal processor (abbreviated as DSP) with a built-in PWM control circuit (not shown) and a high-speed A/D conversion circuit (not shown) for performing PWM control on the inverter circuits 3A, 3B, and 3C. ) and other high-speed processors (not shown), use the grid signal GA to control the inverter circuit 3A to control the compressor motor 4A, use the grid signal GB to control the inverter circuit 3B and drive the rotary drum drive motor 4B, The inverter circuit 3C is controlled by the grid signal GC to drive the blower fan motor 4C, and the control is performed simultaneously at different rotational speeds. Current signals flowing from the current detection circuits 5A, 5B, and 5C to the A/D conversion circuit built in the processor are not shown in the figure.

The structure of the processor will be described later, however, at least one processor incorporates multiple PWM control circuits and multiple A/D conversion circuits, and by synchronizing multiple carrier signals inside the processor, it is possible to realize a The processor has three inverter drive modes. In the case of using two processors and three inverters, it is necessary to synchronize the carrier signal between the processors. However, it has the advantage of reducing the workload of the processors, making the complex sensorless vector control Effectiveness made easy.

FIG. 2 is a detailed circuit diagram of the inverter circuit in the first embodiment of the present invention, and the inverter circuit is formed by a power supply assembly composed of six transistors, diodes, and a control IC.

Here, one U-phase bridge arm 30A of the three-phase bridge arm will be described, a parallel connection body of an upper arm transistor 31a1 composed of an insulated gate bipolar transistor (hereinafter referred to as IGBT) and an antiparallel diode 32a1, and a parallel connection body composed of an IGBT The formed lower bridge arm transistor 31a2 is connected in series with the parallel connection body of the antiparallel diode 32a2, the collector terminal of the upper bridge arm transistor 31a1 is connected with the positive terminal DC power bus terminal P of the inverter circuit, and the emitter terminal of the upper bridge arm transistor 31a1 The terminal is connected to the output terminal U to the motor 4, and the emitter terminal Nu of the lower arm transistor 31a2 is connected to the negative terminal DC power bus 2B through the U-phase shunt resistor 50a constituting the current detection circuit 5. In addition, the ground terminal N of the control IC (gate drive circuit) is connected to the negative-side DC power supply bus 2B.

The upper arm transistor 31a1 is driven by the upper arm gate drive circuit 33a1 according to the upper arm drive signal Up, and the lower arm transistor 31a2 is turned on and off by the lower arm gate drive circuit 33a2 according to the lower arm drive signal Un. The upper bridge arm gate drive circuit 33a1 has a built-in RS flip-flop (flip-flop) circuit that is set or reset by a differential signal. The rise of the upper bridge arm drive signal Up causes the upper bridge arm transistor 31a1 to turn on, and the upper bridge arm drive signal Up rises. Falling makes the high-side transistor 31a1 turn off. The RS flip-flop circuit is not required in the lower arm gate drive circuit 33a2 and is not built in.

The voltage applied to the gate of the IGBT must be 10 to 15V. If the lower-side transistor 31a2 is turned on, the bootstrap capacitor 36a is charged from the 15V DC power supply control terminal VB through the bootstrap resistor 34a and the bootstrap diode 35a. Therefore, by The accumulated energy of the bootstrap capacitor 36a can turn on and off the upper arm transistor 31a1. Also, even when the antiparallel diode 32a2 of the lower arm is turned on, the bootstrap capacitor 36a is charged similarly.

When an overcurrent detection signal is applied to the disconnection signal terminal Of of the inverter circuit 3 , each of the U-phase, V-phase, and W-phase lower-arm transistors of the inverter circuit 3 is instantaneously turned off.

The V-phase arm 30B and the W-phase arm 30C are also connected in the same manner, and the emitter terminals Nv and Nw of the lower arm transistors of each arm are connected to the V-phase shunt resistor 50b and the W-phase shunt resistor 50c constituting the current detection circuit 5 The other terminals of the V-phase shunt resistor 50b and the W-phase shunt resistor 50c are connected to the negative potential terminal N of the DC power supply. If an IGBT or a power MOSFET is used to form the lower-side transistor, switching control can be performed by controlling the gate voltage, so if it is connected to the emitter terminal in the case of an IGBT, or to the source terminal in the case of a power MOSFET If the resistance value is selected so that the voltage of the shunt resistor is 1V or less, there will be almost no influence on the switching operation, and the on and off control can be performed by voltage control, and the voltage of the shunt resistor 50a, 50b, 50c of each UVW phase can be detected. veu, vev, vew can detect the output current of the inverter circuit, that is, the motor current.

Fig. 3 is the detailed circuit diagram of the current signal amplifying circuit that adopts single power supply amplifying circuit to constitute the current detecting circuit 5 of the present utility model, and it utilizes the non-inverting amplifier to pass through the alternating current signal detected by UVW each phase shunt resistance 50a, 50b, 50c Conversion amplification is performed, and the level is converted to a DC voltage level Vcc that can be detected by an A/D converter built in the processor.

Since the UVW phase current signal amplifier circuits 51a, 51b, and 51c are the same circuit, the U-phase current signal amplifier circuit 51a will be described. The peak value of the voltage veu generated in the U-phase shunt resistor 50a corresponds to the U-phase output current of the inverter circuit 3, and the voltage veu of the U-phase shunt resistor varies positively and negatively relative to the ground potential of the current signal amplifying circuit. Since the A/D converter built into a microcomputer etc. operates with a predetermined DC voltage Vcc, it is necessary to set the center value (1/2·Vcc) of the DC voltage Vcc to zero current and follow the change of the relative center value. mode to shift the amplification level. In other words, it is set so that the motor current signal changes within the input dynamic range of the A/D converter.

Connect the capacitor 500a in parallel to the U-phase shunt resistor 50a, connect the first input resistor 501a and the second input resistor 502a in series from the U-phase shunt resistor 50a, and connect the second input resistor 502a to pull up the U-phase current signal On the DC power supply terminal 55 of the amplifier circuit 51a. The connection point of the first input resistor 501a (resistance value R2) and the second input resistor 502a (resistance value R1) is connected to the non-inverting input terminal of the operational amplifier 503a, and between the output terminal of the operational amplifier 503a and the inverting input terminal A feedback resistor 504a (resistance value R4) is connected between them, and a resistor 505a (resistance value R3) is connected between the inverting input terminal and the ground potential to form a non-inverting amplifier. If the resistance value of the U-phase shunt resistor 50a is Ro, then the voltage veu of the shunt resistor 50a becomes the product of the resistance value Ro and the current Iu (veu=Ro*Iu), if the first input resistor 501a and the second input resistor 502a The voltage division ratio k is k=R2/(R1+R2), and the feedback amplification factor K is K=R4/R3, then the output voltage vau of the current signal amplifying circuit 51a is shown in formula 1.

vau=K×veu(1-k)+K×k×Vcc

＝Ro×Iu(K-0.5)+0.5×Vcc (Formula 1)

Here, if the product of the voltage division ratio k and the feedback amplification factor K, that is, k×K=0.5, it is converted to a value corresponding to the current Iu around 1/2 of the DC power supply voltage Vcc of the A/D converter. voltage signal.

For example, assuming that the voltage division ratio k=0.1, the feedback amplification factor K=5, the shunt resistance value Ro=0.2Ω, and the voltage Vcc=5V applied to the DC power supply terminal, the output voltage of the current signal amplifying circuit 51a is vau=0.9 ×Iu+2.5 means. That is, when the DC voltage of the A/D converter is 5V, the central value of 2.5V corresponds to 0A, and the dynamic range can detect a current of approximately ±2.5A relative to ±2.5V.

Resistor 506a and diodes 507a, 508a are connected for overvoltage protection of A/D conversion circuit.

In the current signal amplifying circuit 51a using a non-inverting amplifier illustrated in FIG. If the product (k×K) of the voltage division ratio k of the second input resistor connected to the pull-up and the feedback amplification factor K is approximately 0.5, it can be level-shifted to the center value of the DC power supply voltage (Vcc) of the A/D conversion circuit .

As described above, the current detection circuit of the present invention can perform current detection easily and cheaply with a small number of parts and an operational amplifier with a single power supply. In addition, the current signal of the shunt resistor is amplified by the operational amplifier, so even a low-resistance shunt resistor can detect current, and the loss of the shunt resistor can be reduced, and the shunt resistor can be miniaturized so that the shunt resistor and the current signal amplification circuit can be integrated. miniaturization of current sensing components.

In addition, since the wiring of the shunt resistor and the operational amplifier can be shortened, current detection errors caused by the wiring can be almost eliminated. Furthermore, since the current signal amplifying circuit acts as a buffer, high-speed switching noise is not directly input into the A/D converter, so there is no concern about malfunction or latch-up of the A/D converter. In addition, since the non-inverting amplifier shown in FIG. 3 operates with a single power supply, it is possible to simplify the control circuit DC power supply.

FIG. 4 is a timing chart of carrier signal, PWM control signal, and current detection A/D conversion of the control circuit of the motor drive device shown in FIG. 1 . Ca represents the carrier signal of the inverter circuit 3A, Cb represents the carrier signal of the inverter circuit 3B, Cc represents the carrier signal of the inverter circuit 3C, the carrier frequencies of the carrier signals Cb and Cc are identical and synchronous, and the carrier signals of the carrier signals Ca and Cb Frequency synchronization is set to an integer ratio of 1:4.

Gpa1 and Gna1 are the PWM control signals of the U-phase upper bridge arm and the lower bridge arm of the inverter circuit 3A, and A/Da represents the trigger signal of the A/D conversion circuit that detects the current signal of the current detection circuit 5A. The A/D conversion operation is performed at time t3 of the peak value. Gpb1 and Gnb1 are the PWM control signals of the U-phase upper bridge arm and the lower bridge arm of the inverter circuit 3B, and A/Db represents the trigger signal of the A/D conversion unit that detects the current signal of the current detection circuit 5B. A/D conversion is performed for times t1, t3, and t5 of peak values. Gpc1 and Gnc1 are the PWM control signals of the U-phase upper bridge arm and the lower bridge arm of the inverter circuit 3C, and A/Dc represents the trigger signal of the A/D conversion circuit for detecting the current signal of the current detection circuit 10c. The A/D conversion operation is performed for peak times t2 and t4. The inverter circuit 3B and 3C alternately A/D convert the carrier signal, and the A/D conversion time of the inverter circuit 3A is A/D converted at the time of the peak value (t3) of the carrier signal of the inverter circuit 3B, 3C. Therefore, Mutual interference caused by switching noise can be eliminated.

In the timing diagram of FIG. 4 , there are cases where the A/D conversion times t2 and t4 of the inverter circuit 3C coincide with the switching times of the inverter circuit 3A. If the shunt resistance of the inverter circuit 3C is increased, the common Current sense error due to impedance. In other words, by reducing the output current of the inverter circuit 3C and increasing the shunt resistance compared with the inverter circuits 3A and 3B, the A/D conversion time can be shifted. When the output currents of all the inverter circuits 3A, 3B, and 3C are large, switching noise can be completely eliminated if the A/D conversion time of the inverter circuits 3A, 3B is set to any one of t1, t3, and t5 Current detection error caused by mutual interference.

FIG. 5 shows a block diagram of a current detection assembly with an overcurrent detection circuit added to the current detection circuit. An overcurrent detection circuit 56 is added to the current detection circuit 5 shown in FIG. The overcurrent of the inverter circuits 3A, 3B, and 3C or the motors 4A, 4B, and 4C is thereby detected, and an overcurrent detection signal Fo is output. The overcurrent detection signal Fo is supplied to the external insertion input terminal IRQ of the processor 60a and the output prohibition terminal Of of the inverter circuit, and the output of the inverter circuit is momentarily disconnected. The other structures are the same as those in Fig. 3, and detailed descriptions are omitted.

The current detection circuit 5a is additionally provided with an overcurrent detection circuit 56, an overcurrent output signal terminal 57 and an overcurrent setting terminal 58 on shunt resistors 50a, 50b, 50c, current signal amplifier circuits 51a, 51b, 51c and other terminals as Assemblies, the processor 60a applies a signal Vref corresponding to the overcurrent setting value to the overcurrent setting terminal 58. If the current above the overcurrent setting value flows through the shunt resistor, the overcurrent detection circuit 56 detects the overcurrent, and the overcurrent The current output signal terminal 57 applies an overcurrent signal Fo to the abnormal signal insertion terminal IRQ of the control unit 60a, and the control circuit 60a closes the control signal GA (Up, Un, Vp, Vn, Wp, Wn) of the inverter circuit 3A according to the abnormal insertion signal. .

In addition, since the overcurrent signal Fo is also applied to the disconnection signal terminal Of of the inverter circuit 3A as described in FIG. 2, the output of the inverter circuit 3A is instantaneously stopped. 6. The double protection function constituted by the circuit breaking function of the abnormal insertion signal realizes the overcurrent protection. For the overcurrent caused by the overload of the motor 4 or the overcurrent caused by the out of step, there is no problem with the disconnection response speed of the abnormal insertion signal from the control circuit 6, but in the case of a short circuit between the upper and lower arms of the inverter circuit 3A, it is necessary to If there is a response speed within a few microseconds, the inverter circuit 3A is directly disconnected through the overcurrent signal Fo.

FIG. 6 is a detailed circuit diagram of the overcurrent detection circuit 56 . The overcurrent detection circuit 56 detects the respective terminal voltages of the shunt resistors 50 a , 50 b , and 50 c through voltage comparators, connects the output terminals OR of the three voltage comparators, and outputs an arbitrary overcurrent signal to the overcurrent output signal terminal 57 .

The U-phase overcurrent detection circuit 56a that detects the current of the U-phase shunt resistor 50a converts the voltage signal to veu is applied to the inverting input terminal of the voltage comparator 560a, compared with the set voltage signal Vref applied to the non-inverting input terminal of the voltage comparator 560a, if the voltage signal veu is higher than the set voltage signal Vref, output The terminal voltage drops to Lo. Connect the resistor 563a to the inverting input terminal of the voltage comparator 560a and the circuit power supply voltage terminal Vcc. By applying a positive bias voltage, the abnormal current will flow through the motor and will not be on the inverting input terminal of the voltage comparator 560a. A negative abnormal voltage of -0.3V or more is applied.

The output stage of the voltage comparator 560a is generally constituted by an open-collector transistor, and the output resistor 564a is pulled-up connected so that a logical OR circuit can be easily constituted. The V-phase overcurrent detection circuit 56b and the W-phase overcurrent detection circuit 56c (not shown) are also connected in the same manner, and an OR circuit can be formed by directly connecting the output terminals. In addition, since the set voltage signal Vref is applied to each non-inverting input terminal, if the voltage of any one of the shunt resistors 50a, 50b, and 50c of the UVW phase becomes higher than the set voltage signal Vref, the overcurrent of the effective Lo The signal Fo is output to the overcurrent output signal terminal 57 .

As mentioned above, the current detection circuit of the present invention integrates multiple shunt resistors, multiple operational amplifiers for current signal amplification, multiple voltage comparators for overcurrent detection, and circuit components such as resistors and capacitors. The current detection component, thereby shortening the wiring between the shunt resistor and the operational amplifier, and the wiring between the shunt resistor and the voltage comparator, can not only reduce the pattern wiring impedance, but also reduce the noise caused by the wiring pattern. Therefore, It is possible to reduce malfunction due to noise and perform accurate current detection and overcurrent detection.

Fig. 7 shows the actual installation and configuration diagram of the power supply assembly, power detection assembly and processor on the control substrate of the motor drive device of the washing and drying machine, which is the wiring pattern for the positive and negative DC power supply busbars 2A, 2B, and constitutes the inverter circuit 3A , 3B, 3C of the power supply components 3a, 3b, 3c, each current detection component 5a, 5b, 5c, and the processor 60a of the control circuit 6, the configuration diagram viewed from the component surface. Wherein, the wiring patterns of the positive and negative DC power supply buses 2A, 2B and the processor 60a are usually mounted on the soldering surface, but they may also be on the component surface in the case of reflow soldering.

Electrolytic capacitors constituting a DC power supply (not shown) are arranged on the left side of the front of the figure, and between the positive and negative DC power supply busbars 2A and 2B, in accordance with the order of the output of the inverter circuit, that is, the first inverter for driving the compressor motor 4A. The power supply assembly 3a of the variable circuit 3A, the power supply assembly 3b of the second inverter circuit 3B that drives the rotary drum drive motor 4B, and the power supply assembly 3c of the third inverter circuit 3C that drives the blower fan motor 4C are arranged in order to control the power supply. Assemblies 3a, 3b and the processor 60a that drives the compressor motor 4A and the rotary drum motor 4B are arranged close to the vicinity of the power supply assemblies 3a, 3b, and the negative power supply terminal of the control IC built in the power supply assemblies 3a, 3b is connected to the processor 60a. The grounding terminal of the terminal is connected to the negative DC power supply bus 2B and is wired in a common grounding manner.

The power supply modules 3a and 3b are composed of the components shown in FIG. 2 (excluding capacitors), and are of DIP (Dual In Line) type, and terminals are arranged on both ends of the package. Set high-voltage DC power supply terminal P, U-phase output terminal U, V-phase output terminal V, W-phase output terminal W, lower bridge arm transistor emitter terminals Nu, Nv, Nw on one side of the package, and set on the opposite package side Each gate control terminal Up, Un, Vp, Vn, Wp, Wn, an off signal terminal Of (not shown), and a control IC power supply terminal VB (not shown). Each current detection component 5a, 5b is disposed close to the power supply components 3a, 3b, and the processor 60a controlling the power supply components 3a, 3b is disposed at the shortest position relative to the power supply components 3a, 3b.

The power module 3c of the third inverter circuit 3C that drives the blower fan motor 4C has a built-in current detection circuit 5C, etc., and a motor control IC that drives the motor with a sine wave. The direct current power and the rotational speed control signal applied from the processor 60a constitute an intelligent power supply unit capable of driving the blower fan motor 4C with a sinusoidal wave. In the case of driving the blower fan motor 4C, since the current detection shunt resistor has a large value and the torque fluctuation is small, the fan motor control is relatively easy, because it is not necessary to correctly connect other inverter circuits and carrier signals. Because of synchronization, it is possible to constitute an intelligent power supply module with a built-in motor control IC, and the processor 60a can exclusively control the compressor motor 4A and the rotary drum motor 4B.

In the case of wiring from the emitter terminal of the transistor on the lower arm of the inverter circuit to the negative DC power bus 2B through the shunt resistor, if the wiring becomes longer, the inductance will increase, and the counter electromotive force at the time of switching due to stray inductance will cause IGBT or MOSFET latch-up and damage. In addition, if the wiring between the shunt resistor and the amplifier circuit becomes longer, switching noise will easily enter the signal line, and the detection accuracy will decrease due to the current of the inverter circuit that operates simultaneously through the common impedance.

However, by arranging a plurality of power supply components 3a, 3b, 3c between the wiring patterns of the positive and negative DC power supply busbars 2A, 2B, all of the multiple power supply components are connected from the emitter terminal of the lower-side transistor to the negative DC power supply through the shunt resistor. Wiring on the bus bar 2B becomes easy, and the wiring distance to the processor that simultaneously drives multiple power supply components can be minimized, wiring impedance such as stray inductance can be reduced, and there is almost no general-purpose impedance. The wiring of the /D conversion circuit is also shortened, and the accuracy of current detection can be improved.

Furthermore, by arranging the processor near the power supply unit to shorten the wiring, since it is not easily affected by the high-frequency electromagnetic field generated from the negative DC power bus 2B, there is almost no connection to the gate signal wiring on the power supply unit. Advantages of induced noise (di/dt noise) overlapping with the current signal wiring from the current detection circuit.

As mentioned above, the utility model arranges the compressor motor drive inverter circuit, the rotating drum motor drive inverter circuit, and the blower fan motor drive inverter circuit in parallel relationship between the positive and negative DC power bus bars of the heat pump washing and drying machine. , and a current detection circuit connected to each inverter circuit, at least one processor that simultaneously controls a plurality of inverter circuits is arranged near the compressor motor drive inverter circuit and the rotary drum motor drive inverter circuit, shortening the inverter circuit Ground wiring with the processor and reduce the general impedance, shorten the wiring distance of the gate signal and current detection signal between the inverter circuit and the processor.

In this way, if the wiring distance between multiple inverter circuits and the processor that simultaneously controls multiple inverter circuits and the inverter circuits is shortened, the common ground potential and the reduction of the general impedance can be realized at the same time, and the inverter circuits can be reduced. The superimposition of the induced noise (di/dt noise) caused by switching on the signal line can prevent the malfunction of the overcurrent detection circuit or the A/D conversion circuit built in the processor, and reduce the overlap of switching with the current detection signal. Noise, and can prevent mutual interference when multiple inverter circuits are driven at the same time. In addition, since the wiring distance between the processor and the inverter circuit can be shortened, switching noise superimposed on the gate drive signal from the processor can be reduced, and malfunction of the inverter circuit or damage due to noise can be prevented.

In addition, by detecting the overcurrent of the motor or the overcurrent of the inverter circuit, the malfunction caused by the noise of the overcurrent detection circuit of the momentary shutdown inverter circuit can be reduced, and an accurate overcurrent protection operation can be performed.

Among them, the current detection circuit is described using the three-shunt current detection method, but the effect is basically the same even with the single-shunt method. In order to reduce the influence of switching noise, it is also possible to synchronize the carrier cycles of all inverter circuits for current detection. . In addition, the rotary drum drive motor has a position sensor, so when current estimation is performed based on the applied voltage and the number of rotations, current detection is not necessary, and sufficient control can be achieved with a single-shunt method.

(Embodiment 2)

Fig. 8 shows the processor structure of the control circuit of the motor drive device of the washing and drying machine in the second embodiment of the present invention, and Fig. 9 shows the control board of the motor driving device of the washing and drying machine in the second embodiment of the present invention The actual installation configuration diagram of the power supply components, current sensing components and processor.

Figure 8 shows a dual-processor structure, the first processor 60A1 controls the first inverter circuit (compressor motor drive inverter circuit) 3A and drives the compressor according to the current detection signal (not shown) from the first current detection circuit 5A For the motor 4A, the second processor 60B1 controls the second inverter circuit (rotating drum motor drive inverter circuit) 3B and the third inverter circuit according to the current detection signals (not shown) from the second and third current detection circuits 5B, 5C. The inverter circuit (blower fan motor drive inverter circuit) 3C drives the rotary drum drive motor 4B and the blower fan motor 4C.

Applying the same clock signal ck from the clock circuit 61 to the first and second processors 60A1, 60B1 respectively, by applying the carrier synchronization signal syc from the second processor 60B1 to the plug-in terminal of the first processor 60A1, as shown in FIG. 4, The carrier signal of all PWM control circuits can be synchronized with the A/D conversion circuit. Normally, the carrier frequency of the rotary drum drive motor 4B and the blower fan motor 4C is set to 16kHz, and the carrier frequency of the compressor motor 4A is set to exactly 1/4 of 4kHz. One side applies a synchronization signal, which can improve the synchronization time accuracy.

In Fig. 9, a DC power supply (not shown) is arranged on the left side of the front of the figure. Same as Fig. 7, between the positive and negative DC power busbars 2A and 2B, the compressor is driven according to the order of the output of the inverter circuit. The power supply assembly 3a of the first inverter circuit 3A of the motor 4A, the power supply assembly 3b of the second inverter circuit 3B that drives the rotary drum drive motor 4B, and the power supply assembly 3c1 of the third inverter circuit 3C that drives the blower fan motor 4C The configuration is performed in sequence, the current detection components 5a, 5b, 5c are connected between the power supply components 3a, 3b, 3c1 and the negative DC power bus 2B, the power supply component 3a is controlled by the processor 60a1 and the compressor motor 4A is driven, and the compressor motor 4A is driven by the processor 60b1 The power supply units 3b, 3c1 are controlled to drive the rotary drum drive motor 4B and the blower fan motor 4C. The processor 60a1 is arranged near the power supply unit 3a and between the power supply units 3a, 3b, and the processor 60b1 is arranged near the power supply unit 3b and between the power supply units 3b, 3c1, thereby enabling the processor 60a1 and the power unit The wiring distance of 3a and the wiring distance of the processor 60b1 and the power supply modules 3b and 3c1 are the shortest, so the influence of switching noise or the mutual interference of the inverter circuits can be reduced.

As mentioned above, the utility model arranges the compressor motor drive inverter circuit, the rotating drum motor drive inverter circuit, and the blower fan motor drive inverter circuit in parallel relationship between the positive and negative DC power bus bars of the heat pump washing and drying machine. , and the closest DC power supply is the inverter circuit driven by the compressor motor, the inverter circuit driven by the rotating drum motor, and the inverter circuit driven by the blower fan motor, and the control compressor is arranged near the inverter circuit driven by the compressor motor The first processor of the machine motor, the second processor for controlling the rotating drum driving motor and the air blowing fan motor is arranged near the rotating drum motor driving inverter circuit and the air blowing fan motor driving inverter circuit, so the inverter circuit and the air blowing fan motor are shortened. The grounding wiring of its processor reduces the general impedance and shortens the wiring distance of the gate signal and current detection signal between the inverter circuit and the processor.

Therefore, the common mode noise to the processor and the normal mode noise between the inverter circuit and the processor can be reduced, thereby preventing the malfunction of the inverter circuit, reducing the noise overlapping with the current detection signal, and improving the current detection accuracy. In addition, a plurality of inverter circuits can be actually mounted on one control board, and an inexpensive and highly reliable control board can be realized.

In addition, by shortening the wiring distance between the DC power supply and the inverter circuit for driving the compressor motor, heat generation and common impedance of the wiring pattern can be reduced, so noise tolerance can be improved, temperature rise of the control board can be reduced, and highly reliable heat pump washing can be realized The control board of the dryer.

(Embodiment 3)

Fig. 10 shows the processor structure of the control circuit of the motor drive device of the washing and drying machine in the third embodiment of the present invention, and Fig. 11 shows the control board of the motor driving device of the washing and drying machine in the third embodiment of the present invention The actual installation configuration diagram of the power supply components, current sensing components and processor.

Figure 10 shows a dual processor structure, the first processor 60A2 controls the second inverter circuit (rotary drum motor drive inverter circuit) 3B and drives the rotary drum drive motor 4B according to the grid signal GB, and the second processor 60B2 controls the first The gate signals GA and GC of the inverter circuit (compressor motor driving inverter circuit) 3A and the third inverter circuit (blowing fan motor driving inverter circuit) 3C drive the compressor motor 4A and the blowing fan motor 4C. Applying the same clock signal ck from the clock circuit 61 to the first and second processors 60A2, 60B2 respectively, by applying the carrier synchronization signal syc from the first processor 60A2 to the plug-in terminal of the second processor 60B2, as shown in FIG. 4, A/D conversion circuits of all PWM control circuits can be synchronized with carrier signals. Of course, the sending end of the synchronization signal syc may also be the second processor 60B2.

In Fig. 11, a DC power supply (not shown) is arranged on the left side of the front of the figure, between the positive and negative DC power supply busbars 2A, 2B, according to the order of the instantaneous current of the inverter circuit, that is, to drive the rotary drum drive motor 4B The power supply assembly 3b of the second inverter circuit 3B, the power supply assembly 3a of the first inverter circuit 3A driving the compressor motor 4A, and the power supply assembly 3c1 of the third inverter circuit 3C driving the blower fan motor 4C are arranged in order, The current detection components 5a, 5b, 5c are connected between the power supply components 3a, 3b, 3c1 and the negative DC power supply bus 2B, the power supply component 3b is controlled by the first processor 60a2 and the rotating drum drive motor 4B is driven by the second processor 60b2 controls the power supply units 3a, 3c1 and drives the compressor motor 4A and the blower fan 4C. The first processor 60a2 is arranged near the power supply unit 3b and between the power supply units 3a and 3b, and the processor 60b2 is arranged near the power supply unit 3a and between the power supply units 3a and 3c1, so that the processor 60a2 and The wiring distance of the power supply module 3b and the wiring distance between the processor 60b2 and the power supply modules 3a and 3c1 are the shortest, so the influence of switching noise and mutual interference of inverter circuits can be reduced.

As mentioned above, the motor driving device of the washing and drying machine in the third embodiment of the present invention is the rotating drum motor driving inverter circuit, the compressor motor driving inverter circuit, and the blower fan motor driving inverter circuit according to the closest DC power supply. Arranging in the order of the rotary drum motor driving inverter circuit, the first processor controlling the rotating drum driving motor is arranged near the rotating drum driving inverter circuit, and the compressor controlling compressor is arranged near the compressor motor driving inverter circuit and the blower fan motor driving inverter circuit The second processor of the motor and the blower fan motor, thus shortening the grounding wiring of the inverter circuit and its processor and reducing the common impedance, shortening the wiring distance of the grid signal and the current detection signal between the inverter circuit and the processor.

Since the current of the washing or dehydration stroke of the rotating drum driving motor is much larger than the driving current of the compressor motor, the voltage drop of the negative DC power bus 2B is also large. However, in the drying operation of the compressor motor, the rotating drum driving motor The current is small, so the impact of switching noise on the inverter circuit driven by the compressor motor is small, and the current detection accuracy of the inverter circuit driven by the compressor motor hardly decreases. In order to reduce the switching noise during the washing or dehydration process, it can be configured so that the rotating drum motor drive inverter circuit is closest to the DC power supply.

As mentioned above, the utility model arranges the compressor motor drive inverter circuit, the rotating drum motor drive inverter circuit, and the blower fan motor drive inverter circuit in parallel relationship between the positive and negative DC power bus bars of the heat pump washing and drying machine. , and in the order of the closest DC power supply to the compressor motor drive inverter circuit, the rotary drum motor drive inverter circuit, the blower fan motor drive inverter circuit, or the rotary drum motor drive inverter circuit, the compressor motor drive inverter circuit Circuits, blower fan motor drive inverter circuits are arranged in sequence, by disposing the processor near each inverter circuit driven, the grounding wiring of the inverter circuit and its processor is shortened and the general impedance is reduced, and the connection between the inverter circuit and the inverter circuit is shortened. The wiring distance between the gate signal and the current detection signal between the processors.

Therefore, the common mode noise to the processor and the normal mode noise between the inverter circuit and the processor can be reduced, thereby preventing the malfunction of the inverter circuit, reducing the noise overlapping with the current detection signal, and improving the current detection accuracy. In addition, a plurality of inverter circuits can be actually mounted on one control board, and an inexpensive and highly reliable control board can be realized.

In addition, by shortening the wiring distance between the DC power supply and the inverter circuit for driving the compressor motor or the inverter circuit for driving the rotary drum motor, it is possible to reduce the heat generation and general impedance of the wiring pattern, and to reduce the radiation noise caused by the large current loop. Noise tolerance and reduced temperature rise of the control board can realize a heat pump type washer-dryer control board with high reliability even if multiple inverter circuits operate at the same time.

Claims (5)

1. the motor drive of a scrubbing-and-drying unit is characterized in that, comprising:

DC power supply;

DC power supply bus from the positive and negative of described direct-current power supply direct current power;

Convert the direct current power of described DC power supply to alternating electromotive force, and drive air compressor motor, the swing roller motor of heat pump, first, second, third inverter circuit of Air Blast fan motor respectively;

The a plurality of current detection circuits that are connected with described a plurality of inverter circuits; With

Control the control circuit of described a plurality of inverter circuits, wherein,

Described a plurality of inverter circuit parallel connection is configured between the DC power supply bus of described positive and negative.

2. the motor drive of scrubbing-and-drying unit according to claim 1 is characterized in that:

Described first inverter circuit is configured to the most approaching described DC power supply.

3. the motor drive of scrubbing-and-drying unit according to claim 1 is characterized in that:

Described control circuit has a directly processor of described first and second inverter circuits of control at least,

Described processor be configured in described first and second inverter circuits near.

4. the motor drive of scrubbing-and-drying unit according to claim 1 is characterized in that:

Described control circuit has the first processor of described first inverter circuit of direct control and directly controls second processor of the described second and the 3rd inverter circuit,

Described first processor be configured in described first inverter circuit near,

Described second processor be configured in the described second and the 3rd inverter circuit near.

5. the motor drive of scrubbing-and-drying unit according to claim 1 is characterized in that:

Described control circuit has the first processor of described second inverter circuit of direct control and directly controls second processor of the described first and the 3rd inverter circuit,

Described first processor be configured in described second inverter circuit near,

Described second processor be configured in the described first and the 3rd inverter circuit near.

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