| 摘要 |
PURPOSE:To reduce the load voltage at interruption and to decrease the dielectric strength at load side, by performing off-operation of a plurality of thyristor switch circuits in series connection when a load is interrupted, through shifting timewise. CONSTITUTION:A DC power supply 1 is constituted with a load branching circuit where a main switch circuit 3, loads 21-2n in parallel with the circuit 3, a series circuit of auxiliary switch circuits 41-4n in series. In this case, a load opening signal SCB turns off the main switch circuit 3 by giving a trigger current of an axuiliary thyristor 32 to the circuit 3 from a control circuit 7 via gate trigger circuit 5 and 61-6n. In this case, a load voltage is the sum of a voltage eC1 of a commutating capacitor 33 and a power supply voltage EC. Next, after the voltage eC1 is discharged through the interruption of the circuit 3, for example, the auxiliary switch circuit 41 turns off to make the load voltage to be the sum of the voltage eC2 and the EC. |
