TWO-LEVEL FREQUENCY CONVERTER ON SHUTOFF VALVES Russian patent published in 2012 - IPC H02M5/297 

FIELD: electricity.

SUBSTANCE: unlike the traditional current inverter design, the proposed circuit is based on transistor keys with unidirectional conductance and a damping device connected parallel to the motor stator windings. The device core element is a polar capacitor participating in two-stage performance of phase currents commutation with the help of additional transistors.

EFFECT: one achieves the effect of smooth current variation at a limited level of commutation overvoltage, reduction of weight and dimension indicators and elimination of charge accumulation on the damping capacitor armature without excessive commutation energy dispersion in the discharge resistor.

5 dwg