FORCED SWITCHING UNIT FOR POWER THYRISTORS OF OFF-LINE THREE-PHASE VOLTAGE INVERTER Russian patent published in 1998 - IPC

FIELD: converter engineering; three-phase voltage supply to resistive-inductive loads. SUBSTANCE: forced switching unit has circuit set up of series-connected first controlled switch, switching capacitor, and second controlled switch, this circuit being inserted between inverter poles, and three-phase bridge of switching thyristors whose poles are connected through respective switches to respective inverter poles and its phase leads are connected to respective phase leads of inverter; newly introduced in unit is choke coil inserted in series circuit and connected to switching capacitor. Circuit obtained from choke coil and capacitor is shorted out by thyristor connected for recharging. Thyristors are used as controlled switches. EFFECT: simplified design of unit dispensing with switching capacitor in charging source; reduced switching loss. 1 dwg