| 摘要 |
PURPOSE:To perform the interrupting operation of a semiconductor element by forming a series circuit of a switch connected in parallel with the semiconductor element and a condenser to compose a closed circuit of the semiconductor element, a switch element and the condenser. CONSTITUTION:A condenser 10 is charged by a charger 11, and a series circuit with a switching element 12 shortcircuits a gate turn-off thyristor (GRO)4a. When an overcurrent flows through the GTO4a, a detection signal is fed to a switch element 12 by the signal from a current detector 9. The element 12 is conducted, the energy stored in advance in the condenser 10 is discharged sequentially through the condenser 10, a flywheel diode 4b, the switch element 12 and the condenser 10, and the GTO4a is interrupted by applying a reverse voltage to the GTO4a. |
