SU1465206A1 - Generator of unipolar pulses - Google Patents

Abstract

The invention relates to power converter technology, in particular, to pulse generators for EDM machines, and can be used in the metalworking industry. The purpose of the invention is to increase reliability. The generator contains thyristors 1-4, 17-21, diodes, chokes, capacitors and resistors, as well as sources 16 and

Description

: .one

: The invention relates to a power reforming technique, in particular to a pulse generator for electrical erosion machines, and can be used in the metalworking industry and in other national economic sectors.

The purpose of the invention is to increase the reliability of work.

In the drawing there is an electrical schematic diagram of the proposed generator.

The generator of unipolar impunces contains the first, second, third and fourth thyristors 1-4, the first, second, third and fourth, fifth and sixth diodes 5-10, the first and second capacitors 11 and 12, the first and second chokes 13 and 14 , output terminals - We are 15 electroerosive gap, the first power source 16, the anodes of the first and second thyristors shunted by the corresponding first and second diodes 5 and 6, inserted into the opposite direction, are interconnected, the cathode of the first thyristor 1 is connected to the anode of the third thyristor 3, the cathode third diode 7 and black In series, the first capacitor 11 and the first choke 13 are connected to the cathode of the second thyristor 2, the anode of the fourth thyristor 4 and to the cathode of the fourth diode 8, the anode of which is connected to the anode of the third diode 7, the first electrode 15 of the electroerosal gap and the anode of the fifth diode 9 whose cathode is connected to the first plate of the second coN of the capacitor 12 and the anode of the sixth diode 10, the cathode of which is connected to the cathode of the third and fourth thyristors 3 and 4, fifth, sixth, seventh, eighth and ninth thyristors 17-21,

the third capacitor 22, the second power source 23, the seventh and eighth diodes 24 and 25, the third inductor 26, the positive bus of the first power source 16 is connected to the second plate of the second capacitor 12 and the anode of the first thyristor 1, the negative bus of the first power source 16 is connected to the seventh anode the diode 24, the cathode of which is connected to the anode of the sixth diode, and the connector through the second choke 14 with the anode of the fifth diode and the negative bus of the second power source 23, the positive bus of which is connected to the anodes of the fifth

and sixth thyristors 17 and 18, the cathodes of which are interconnected via a third capacitor 22 and connected to the anodes of the seventh and eighth thyristors 19 and 20, respectively, the cathodes

which are interconnected and connected to the anodes of the eighth diode and ninth thyristors, the cathode of the eighth diode 25 is connected to the cathode of the fourth thyristor 4 and through the third choke 26 to the cathode of the ninth thyristor 21.

The control unit can be performed on the first and second formers 27 and 28 antiphase pulses

and a driver 29 of control pulses connected respectively to the control inputs of the first, second, third, fourth t-4, fifth, sixth, seventh

and the eighth thyristor 17-20, and the ninth thyristor 21. The inputs of the first

20

25

and the second formers 27 and 28 of antiphase pulses are connected via the corresponding ninth and tenth diodes 30 and 31 with the corresponding first and second oscillators 32 and 33, the first trigger inputs of which through the corresponding first and second switch 34 and 35 are connected to the output trigger 36 and the first input element I 37, the output of which is connected through the eleventh diode 38 to the input of the second driver 28 antiphase pulses, and the second input of the element I 37 connected to the input of trigger 36 and through the driver 39 of the emergency pulse to the inverter pin 40 connected in series with the first choke 13, the S input of the trigger 36 is connected via the Start button 41 and through the resistor 42 respectively to the first and second power buses 43, 44, the input of the control pulse generator 29 is connected via the twelfth diode 45 to the output the second master oscillator 33 and, through the one-vibration 46, to the second trigger input of the first master oscillator 32,

The generator in the steady state works as follows.

At this time, let the capacitors 11, 12, and 22 be charged with the polarity indicated in the drawing. With

turning on the Start button 41 to the S input of the trigger 36 is applied O, and the keys 34, 35 are locked. As a result, the generator 33 starts up, the driver of the driver 28, which generates control pulses. At the same time, a pulse from the master oscillator 33 starts: the driver 29, which controls the thyristor 21, and the one-oscillator 46. As a result, the master generator 32 starts, the antiphase pulse driver 27 will generate the control pulses for a time determined by the output time pulses of one-shot 46, which can be controlled within wide limits. The duration of the pulses of the one-shot 46 determines the duration of the output pulses of the generator, the repetition frequency of which is determined by the frequency of the setting of the generator 33.

Let at a given moment of time the control pulses are fed to the corresponding diagonal Tiris pairs.

thirty

40

45

55

20

25

Yu

„

465206

torus 17-20, thyristor 21 and thyristors 1.4. Initially, an ignition part of the output pulse is formed with a high steepness of the leading edge and a large amplitude, since at the first moment the thyristor 21 and thyristors 17, 20 are turned on and the total voltage on the capacitor 22 and the power source 23 is applied to the load. There is a breakdown of the electroerosive gap (load) 15, the voltage on it begins to fall off exponentially, and the capacitor 22 starts to recharge on the opposite side.

polarity Further, when the voltage decreases at the load 15, thyristors 1.4 turn on and the oscillating current of capacitor 11 overcharges 11 through the elements 12, 1, 11, 13, 4, 26.15, 9, and 12 begins to flow through it. 11, counter-diodes 5, 8 are turned on, and a current through the load flows in the same direction along the circuit of elements 11, 5, 12, .10, 26, 15, 8, 13 and 1.1. Further, when the diodes 5, 8 are turned off, the thyristors 2, 3 are turned on and the process is repeated, thereby forming the working part of the generator pulses, the duration of which is determined by the duration of the output pulse of the single-vibrator 46. In the process of forming the working part when the thyristors current decreases and oncoming diodes, the first diode 24 is turned on, and then the current of the throttles 14 is closed along the circuit of elements 14, 24, 10, 26, 15 and 14, i.e. there is a discharge of energy stored in throat village 14 into the load circuit. The energy accumulated in the inductance of droplets 26 is also released, and the current can be closed along the circuit of elements 26, 15, 9, 10 and 26. All this allows to obtain a smoothed working part of the pulse, which allows to increase efficiency and reliability generator. After the formation of the working part is completed, after some time determined by the frequency of operation of the master oscillator 33, the control pulses are applied to the next thyristors of the bridge, the thyristor 33 and the thyristors of the first bridge, and the formation of the second pulse of the generator begins.

In the event of a breakdown of the inversion, for example, when the th

40

45

55

Ristors 1 and 3, the sensor 40 generates a signal to start the emergency pulse shaper 39, which generates signals with the required parameters. These signals are sent to the R input of the trigger 3j6 and the second input of the element 37, to the first input of which a signal from the trigger output 36, which, when applying an emergency impulse to the R input, unlocks the trigger K: keys 34 and 35, as a result of which the control pulses of the first and second bridges are blocked (thyristors 1–4 17–20). At the same time, the output signal m | rigger 36 is fed to the first input of the epimete. And 37, when the signal & B coincides, it gives a signal to once form the next control pulses of the corresponding thyristors 1: 7-20 of the bridge, As a result - P1; the thyristors 1, 3 apply a reverse voltage equal to the sum of the voltages of the source 23 and the capacitor 22, and these thyristors are turned off and the ai capacitor 22 is recharged by a Cherkez diode 25, a choke 26 and a load 1S.

; The introduction of additional elements into the generator significantly improves the reliability of operation and expands the functionality of the generator by completely limiting emergency currents, by impulses of high-torque rise and amplitude of the igniting part, and by the smoothed working part, regulation. frequency and duration of pulses in a wide range.

Claims (2)

1. A generator of unipolar W pul-GOBJs containing the first, second, third and fourth thyristors included in the thyristor bridge, the first, second, third, fourth, fifth and sixth diodes, the first and second capacitors, first and second chokes, electroerosion gap electrodes, first power source, first and second thyristors, pnunted respectively by the first and second diodes connected in the opposite direction, the cathode of the first thyristor eoed1-shen with the anode of the third thyristor cathode of the third diode and through dia-- - 1 onal thyristor bridge in series connected to the first capacitor and the first choke The second thyristor cathode, the fourth thyristor anode and the fourth diode cathode, the anode of which is connected to the anode of the third diode, the first electrode of the electroerosion gap and the anode of the fifth diode, the cathode of which is connected to the first plate of the second capacitor and the anode of the sixth diode whose cathode is connected to the cathodes The third and fourth thyristors, characterized in that, in order to increase the reliability of operation, the fifth, sixth, seventh, eighth and ninth thyristors, third capacitor, second power supply, seventh and eighth diodes, third choke, positive bus of the first power source connected to the second plate of the second capacitor and anode of the first thyristor, negative bus of the first power source connected to the anode of the seventh diode, the cathode of which is connected to the anode the sixth diode, and through the second choke is connected to the anode of the fifth diode and the negative bus of the second power source, the positive bus of which is connected to anodes of the fifth and sixth thyristors, the cathodes of which are interconnected through a third capacitor and connected to the anodes of the seventh and eighth thyristors, respectively, the cathodes of which are interconnected and connected to the anodes of the eighth diode and the ninth thyristor, the cathode of the eighth diode is connected to the fourth cathode thyristor and through the third choke - with the cathode of the ninth thyristor and the second electrode of the electroerosion gap. 2. Generator pop, 1, is different from that, in order to increase reliability, the control unit is made on the first and second antiphase pulse generator and the control pulse generator connected respectively to the control inputs of the first, second , third, fourth thyristors, fifth, sixth, seventh and eighth thyristors and ninth thyristors, the inputs of the first and second forphase impulses are connected through the corresponding ninth and tenth diodes with the corresponding first and second master gene ato. 1 1A652068 frames that start up the inputs in sequence of the corresponding first and second axes into the thyristor cut diagonal, the S-input of the trigger connectors are connected to the output triggered by the Start button and through the re- and first input of the output resistor respectively with the first and which is connected through one hand - the second power bus, the input of the formed diode to the input of the second driver for controlling impulses of the antiphase impulse connectors, and the second through the twelfth diode with the input of the element AND connected to the input of the second master for generators and through the row latch and driver, through a second monostable multivibrator with zapuska- emergency impulse - a sensor EASURES yuschim-input of the first master gene- va inverting included pos-operators.