| 摘要 |
PURPOSE:To prevent the generation of overvoltage into AC system by a method wherein, when a trouble happens at one end of AC-DC converter connected to an AC system, the cnverter at the trouble side is turned in bypass pair to stop the converter after zero power-factor operation. CONSTITUTION:The DC transmission system is formed so that DC and AC may be converted from each other by means of connecting the converters 3, 3' comprising multiple thyristors with AC, buses 1, 1' to control each thyristor through the intermediary of the transformers 2, 2'. When a trouble happens in the AC systems 1', the power inverter 3' is turned in a bypass pair actuating level detector 24 to transfer switches 22, 23 and a control angle of lag of setter 21 is provided to put the system into zero-power factor operation disconnecting SC 17 later to gate block the power rectifier 3. Through these procedures, when a trouble happens, said converters 3, 3' may be very rapidly stopped without generating overvoltage in AC system. |
