SU1584045A1 - Dc voltage-to-pulsing voltage converter - Google Patents

Abstract

The invention relates to electrical engineering and can be used as a pulsed current source. The purpose of the invention is to enhance the functionality and improve the quality of the output voltage. The device includes a capacitive energy storage (ENE) 1 connected to a constant voltage source 2 and a load 3 connected in series and a switching bridge on controlled power switches 4-7. The forming line (FL) 8 is connected to the diagonal of this bridge 8. Keys 4 , 5 are shunted by reverse diodes 9, 10. The load is shunted by key 11, the anode of which is connected to the positive terminal of ЕНЭ 1, through resistive-diode chains. In normal operation, the formation of current fronts in the load occurs by switching on keys that commute almost non-inductive circuits, and the steepness of the fronts is limited only by the parameters of the instruments used. The width of the current pulse in the load is controlled smoothly within the width of the pulse of the current FL 8. When the load resistance decreases or during a short circuit in the load circuit, the key 11 does not turn on and the current pulse in the load is limited by the width of the FL pulse 8, the process of recharging and limiting the voltage as in the case of feeding a normal load. 3 hp f-ly, 3 ill.

Description

(L

with

This bridge is turned on forming line (PL) 8. Keys 4, 5 are shunted by reverse diodes 9, 10. The load is biased by key 1I, the anode of which is connected to the positive terminal ЕНЭ 1, through resistive-diode chains In normal mode and front formation the current in the load occurs by switching on keys that commute almost inductive circuits8 and the steepness of the fronts is limited only by parameters

used pribpol. The width of the current pulse to the load is adjusted smoothly in the limit of the current width of the fluorescence fluorescent fluorescent fluorescent light source. When the load resistance decreases during a short circuit in the load circuit, the key i1 does not turn on and the current fluorescence pulse is limited by the pulse width of the fluence happens as in the case of writing normal ngrueki. 3 з.п about f-ly, 3 ill.

The invention relates to electrical engineering and is intended for use as a source of a sequence of short unipolar high-power rectangular current pulses of adjustable duration with a limited amplitude of current pulses at a predetermined level with a sudden increase in load resistance.

The purpose of the invention is to develop non-functional capabilities for improving the quality of the output voltage.

FIG. 1 and 2 are schematic diagrams of a voltage-to-pulse voltage converter; n FIG. 3, diagrams, long descriptive operation of a converter,

The converter (FIGS. I and 2) contains a capacitive energy storage device 1 (THNE) powered from a constant voltage source z, and a load circuit HLJ 3 and a switching bridge akz of controlled power switches 4-7. The bridge and the load are connected in series. The cathode pole is connected to the negative output of the EH3S. The positive output of the EHE is connected to the load. The forming line 8 (FL) “Controllable keys 4 to 5 of the cathode group of the shuntyrose bridge are connected with the opposite side of the diode 9 and 10. a controlled power switch 11, the anode of which is connected to the positive terminal of the UNE 1. Both ends of the FL 8 are connected to the positive terminal of the UNE 1 through resistor-diode chains 12-13 and 14-1b. Anodes of diodes 12 and 14

connected to the FL

and cathodes - with resis0

3

0

five

0

five

five

with tori 13 and 15, respectively. The driver of the control pulses 16 (FIU) is connected to the control unit of the power switches 4-7 and 11.

The value of the capacitance of the ENE 1 is determined from the condition of providing a given pulse shape over the entire range of possible loads.

The type of FL 8 is selected according to the requirements for the pulse parameters at the load and taking into account the technological efficiency of the line construction. The parameters of the PL, such as the number of links, the values of the reactivities of each link, the ratio of the wave resistance of the PL and the load, determine the pulse duration, its front, the cut, and the oscillations on the top. The manufacturability of the construction of the PL dictates the need to select this type of line, where the reactivity values of all the units are the same. It is advisable to provide a correction FL element to obtain a pulse shape that is closer to a rectangular one.

FIG. 3, on axis 17, narrow m.pulses of control are shown that unlock x..guards 4–7 and 11; on axis 18, the fluorescence flux and ca. flowing through the key. 7, 8 or 6, respectively, in the first or second cycle of the converter, the time tT j corresponds to the beginning of the pulse

current in the FL, time tg - the beginning of the current pulse in the load, the time te - the moment-shunting of the load, the time t 4 to the moment the FL current passes through

Zero axis 19 shows the current pulse ij in the load, the duration Ti of the current pulse of the load. The axis 20 shows the voltage U fflf, the voltage

v u is the initial voltage on

with

PL, voltage Ue / v, is the maximum voltage on the PL after it is recharged, the voltage 4U corresponding to the difference of the maximum voltage to which the PL can be recharged and the initial voltage on it. Charts 21-24 are diagrams showing the operation of the converter when the amplitude of the current pulse in the load is limited when the load resistance deviates from the specified value or during a short circuit in the load circuit. On axis 21, narrow control pulses are shown, unlocking the keys 4-7 and 11. On the lights 22 and 22, the currents i-fl of the forming line and the current i 7 are shown, keys 7 and 6, time t g- start of the current FL pulse, time 11 - the current pulse in the load, time t7 is the moment of load shunting with the controlled key 14, time tg is the moment of the transition of the FL current through zero. On axis

shows the current pulse i in load23

ke, the current pulse i e (ke) in the load at short circuit in whose. On axis 24 showed voltage.

In the standard mode of operation, the formation of a current pulse in the load is performed by the converter as follows.

With charge of FL 8 in the polarity shown in FIG. 1, prior to the voltage of the power source 2 from the FIU 16, a trigger pulse is applied to the key 4. An FL circuit 8 is formed - a key 4 - a diode 10 FL 8, in which the current i AL has the form shown in FIG. 2 (axis 18). With some delay, the smallest value of which is determined by the capacitance of the leading edge of pulse i, switch 7 is turned on, and the current in load 3 and switch 7 quickly increases to the steady state value of the ENE circuit 1 - load 3 - switch 7 - diode 10 - ENE 1. In normal mode, the resistance of the load 3 is greater than the resistance of the forming line, which is why the diode 10 does not turn off. After a time interval Tn, equal to the specified pulse width tola in the load, at time tj switches on key II, to which the load current passes at high speed determined by the switch-on time of switch 11. Current in switch I stops i, and current through switch 7 increases to the amplitude of the current

ten

40456

FL i FL through the circuit ЕНЭ 1 - key 11 - key 7 - diode 10 - ЕНЭ 1. When the current i l and 17 are reached, diode 10 is turned off and FL is inserted into the circuit instead of it, limiting the current at the reached level of current amplitude. In the future, there is an ENEA circuit 1 - a key 11 - a key 7 - FL 8 - a key 4 - ENE 1, on which the recharge of the FL to the voltage of the AC / I is completed to a higher initial value Ufr0 (axis 20), since the charging circuit has an oscillatory character Thus, in normal operation, the formation of current fronts in the load occurs by turning on keys that switch almost non-inductive circuits, and the steepness of the fronts is limited only by the parameters of the instruments used. The width of the current pulse in the load is adjusted smoothly within the width of the current pulse FL.

15

20

At time t4, the current i RL changes direction, since the PL begins to discharge the diode 14 through the circuit - the resistor 15 reaches the value of the voltage of the ENEA 1 power source. When the PL voltage is established, the first cycle of the converter operation ends. The second cycle of work is identical to the first, but other elements participate in the work (in Fig. 3 are shown in parentheses),

Consider the process of limiting the amplitude of a current pulse in a load when deviating to the side of decreasing the load resistance from a given value or when a short circuit occurs in the load circuit, which is illustrated by diagrams on axes 21-24 (Fig. 3).

At time ts, key 4 is unlocked and a current i occurs in the FL circuit 8 - key 4 - diode 10 FL 8

M

At time t

unlock key 7 and in the circuit ЕНЭ 1 - load 3 - key 7 - diode 10 - ЕНЭ 1 increases the current to the magnitude of the amplitude 1fl. Upon reaching equality of these currents, the diode 10 is turned off, and the current 1E in the load 3, and the current i in the switch 7 are limited at the achieved level of the amplitude of the current i FL. There is an ENEA circuit 1 - load 3 - switch 7 - FL 8 - switch 4 - ENE 1. At time t7, switch 11 that shunt the load is unlocked, and if the load resistance is noticeably different from zero, current 13 (axis 23) switches to switch 11, and the impulse in the load ceases. In the event of a short circuit in the load, the switch 11 does not turn on and the current pulse in the load is limited by the width of the PL pulse.

The process of overcharging and limiting the voltage of the PL occurs as in the case of feeding a normal load.

The converter is designed to operate in the entire power range to form a current rectangular | Muls on a previously unknown load with a limited amplitude of current pulses. Since the duration of the current pulse in the load cannot be longer than the duration of the recharge of the PL, the converter is designed to form short current pulses.

Claims (4)

1. DC-to-pulse voltage converter, containing a capacitive energy storage device connected to a DC voltage source, controllable power switches, a bridge control system of power switches and reliable terminals for connecting, a load, and a cathode pole the bridge of the power switches is connected to the negative terminal of the capacitive energy storage, the positive terminal of which forms one of the output terminals and the other output terminal is formed by the anode pole of the specified bridge, which distinguishes in that, in order to expand functional and capabilities and improving the quality of the output voltage; a line is additionally introduced into the diagonal bridge; a line is formed, and each of the power switches, whose cathode is connected to the negative pole of the capacitive energy storage device, is shunted by one of the additionally introduced reverse diodes. 2. The converter according to claim 1, is whether it is between the output terminals for connecting the load circuit to include an additionally introduced controllable power switch, the anode of which is connected to the positive pole of the capacitive energy storage device. 3. The Converter in PP. 1 and 2, characterized in that, in order to limit the overvoltages on the condensate of the forming line during the formation of sequences of pulses, both ends of the forming line are connected to the positive pole of the capacitive energy storage through the corresponding additionally introduced resistive-diode circuits. 4. The converter according to claims 1-3, characterized in that the controlled power switches of the bridge, the anodes of which are combined, and the controlled power switch connected between the output terminals made in the form of reversible switches, and the power switches, in which the cathodes are combined, are made in the form of thyristors. 17 Fig.Z