| 摘要 |
PURPOSE:To dispense with an auxiliary power source and simplify a gate circuit for a gate turn-off thyristor, by charging the capacitor of the gate circuit by the discharging current of a capacitor coupled in parallel with the thyristor. CONSTITUTION:The cathode of the gate turn-off thyristor 11 is connected in series with the primary winding of a current transformer 21. The capacitor 14 of the gate circuit for supplying a negative gate signal to the thyristor 11 by a current flowing through the secondary winding of the current transformer 21 is charged by the discharging current of the capacitor 23 coupled in parallel with the series circuit consisting of the cathode of the thyristor and the primary winding of the current transformer. Since the capacitor 14 which stores energy for turning off the thyristor 11 is charged by the discharging current of the capacitor 23 through the current transformer 21, the auxiliary power source for charging the capacitor 14 is not needed. Therefore, the gate circuit is simplified. |
