SU401461A1 - PULSE CURRENT GENERATOR INVERTER TYPE - Google Patents

Description

one

The present invention relates to the field of electrophysical processing methods and, in particular, concerns a current pulse generator for electroerosive metal processing.

Inverter-type current pulse generators with a capacitive drive and throttles connected in series with controllable keys are known.

A disadvantage of the known generators is that they do not provide an average voltage on the load equal to 1 bar, which leads to a decrease in the efficiency factor. generator.

The purpose of the present invention is to provide an average voltage at a load of zero.

The supply is achieved by the fact that the chokes are provided with additional windings with oppositely directed magnetic fluxes, respectively, included in the opposite shoulders of the inverter.

The drawing shows the electrical circuit of the proposed generator.

The generator consists of a power supply 1, two controllable keys (thyristors) 2 and 3 connected in series with throttles 4 and 5, capacitive storage 6 and erosion gap 7. Throttles 4 and 5 in thyristors penes 2 and 3 are made of multiwinding. Choke 4 has three windings 8-10, and choke 5 -

two windings 11 and 12. As can be seen from the diagram, the magnetized flows created by windings 8 and 9, I and 12, are directed oppositely.

With a reduction in the dimensions of the chokes 4 and 5, the number of turns Ws and Wg of windings 8 and 9 and, accordingly, the number of turns Wn and Wi of windings 11 and 12 are different:

.

This selection of BITKET chokes provides

the mode of complete reversal of their magnetic circuits.

The generator works as follows. When opening the thyristor 2 from the power source 1 by the penalty: thyristor 2, winding 8, choke 4, capacitor 6, secondary winding 9 droplets 4, erosion gap 7 - the charge current pulse passes, causing the capacitor to charge and thyristor 2 to close. After restoring the locking

the properties of thyristor 2, a signal is given to open thyristor 3 and along the circuit: capacitor 6, winding 11 droplets 5, thyristor 3, erosion gap 7, secondary winding 12 drossels 5 - a discharge current pulse passes, after which the thyristor 3 closes. Further, the operation of the generator circuit is repeated.

Since the magnetic fluxes generated by the windings 8 and 9, 11 and 12 are directed oppositely, when opening, for example, the thyristor 2

choke 4 practically does not limit the amplitude of the current. The current pulse through the erosion gap 7 when it passes through the circuit. If the erosion gap does not penetrate when the thyristor 2 is opened, then the current circuit through the thyristor 2 closes on the winding 12 droplets 5. To the erosion gap, the sum of voltages is applied, equal to the voltage drop on the winding 12 droplets 5 and the voltage induced in the winding 9 Drossel 4.

To limit the overvoltage on the elements of the heater circuit, the choke 4 is equipped with a third winding 10 connected via a valve 13 to the power supply. The degree of limitation of overvoltage on the circuit elements is determined by the magnitude of the transformation ratio between the windings 8 and 10 of the choke 4.

Subject invention

Claims (2)

1. An invertor-type current pulse generator for electrical erosion of metal processing, with a capacitive drive and throttles connected in series with controllable keys, characterized in that, in order to ensure an average voltage on a load equal to zero, the chokes are equipped with additional windings oppositely directed magnetic fluxes, respectively, included in the opposite shoulders of the inverter. 2. The generator according to claim 1, characterized in that, in order to limit overvoltages to the circuit elements, the choke, turned on in the adjacent circuit, is supplied with a third winding connected to the SOURCE of the power supply.