| 摘要 |
PURPOSE:To prevent in advance the damage of a gate turn-OFF thyristor GTO and to enable stable operation of the GTO by always supplying the ON gate current of the GTO in a zone where the GTO is desired to be conducted ON. CONSTITUTION:ON and OFF gate generators 21, 22 are composed of DC power sources 211, 221, resistors 212, 222, photocouplers 213, 223, and transistors TR214, 224, and an ON gate power source 23 of a gate turn-OFF thyristor GTO28, OFF- gate power source 25, resistors 24, 27 and current amplifying TR26 are provided. The output current of the power source 23 flowed through the resistor 24 is all flowed through the resistor 27, the power source 25 and the TR26, and the ON- gate current flowed to the GTO28 is eliminated, the output current of the power source 25 is instead flowed as the OFF gate current to the GTO28 through the resistor 27 and the TR26. |
