| 摘要 |
PURPOSE:To increase a conrollable anode current, by applying a DC power to the gate when a gate turn-off thyristor (GTO) is turned off and by dividing this DC power and applying it to the gate. CONSTITUTION:When a turn-off signal is outputted from a turn-off signal generating circuit 30, an output voltage of a DC power source 24 higher than the breakdown voltage is applied across a gate G and a cathode K of a GTO10. Then, a gate current iG is flowed, and an anode current iT and a voltage VG-K between the gate G and the cathode K drop. Next, a turn-on driving signal of a transistor 28 disappears, and a voltage of the DC power source 24 divided by resistances R1 and R2 is applied across the gate G and the cathode K of the GTO10. This divided voltage is set to a voltage lower than the breakdown voltage. |
