METHOD AND DEVICE FOR PULSE-PHASE CONTROL OF CONVERTER THYRISTORS Russian patent published in 2012 - IPC H02M1/08 

FIELD: electricity.

SUBSTANCE: in the method of pulse-phase control of converter thyristors consisting in generation of pulses of thyristor control at the moments of comparing sinusoidal sweep voltages with permanent control voltage, in antiphased channels of the device for pulse-phase control of thyristors one and the same sinusoidal sweep voltage is applied, at the same time in one channels of the device control pulses are generated at the moments of comparing ascending branches of sinusoidal voltage curves with one control voltage, and in antiphased channels - at the moments of comparing descending branches of curves of the same sinusoidal voltages with the other control voltage, which is proportionate to the first control voltage and has an opposite polarity relative to it. The device for pulse-phase control of converter thyristors, comprising windings of transformer synchronisation, filters, double-input comparators, and a unit for matching of control voltage, additionally comprises an analog inverter, which is connected to an output of the unit for matching of control voltage, at the same time some inputs of each pair of comparators of antiphased channels of the device are connected via the common filter to one and the same winding of transformer synchronisation, besides, the second inputs of some antiphased channels from each pair of comparators are connected to the output of the unit for matching of the control voltage, and the second inputs of other ones from each pair of comparators - to the output of the analog inverter. Using the proposed method of pulse-phase control in a multi-channel device of converter thyristor control makes it possible to produce a technical result - to simplify its circuit implementation. Thus in a six-channel version of the device, instead of six windings of transformer synchronisation and six filters, only three synchronisation windings and three filters are used. At the same time using one and the same sinusoidal sweep voltage in two antiphased channels of the control device makes it possible to increase symmetry of thyristor control pulses in these channels. Besides, using the additional input of the analog inverter of the control device makes it possible to provide for symmetrical current load of antiphased thyristors of a high-current converter even in case of a non-symmetrical structural version of its power circuit. The specified advantages are most substantially evident, when the proposed device is used for control of thyristors of a six-phase (double three-phase) rectification circuit with a paralleling reactor, which found wide application in high-current low-voltage converters to supply electroplating baths.

EFFECT: implementation of the proposed method for pulse-phase control makes it possible to simplify the circuit technology of the thyristor control device and to increase reliability of operation of the entire converter as a whole.

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