高压直流换流器单阀触发导通的基本电路分析

Analysis of Basic Circuit of Single Valve Conduction of HVDC Converter

高压直流输电工程调试是建设的最后环节,对期间的电气量录波进行分析涉及到单阀触发导通及电流不连续工况的理论问题。高压直流输电系统晶闸管的触发采用单脉冲等间隔触发方式,解锁期间出现换流器单阀间歇导通等情况,需配置补脉冲功能才能使两阀导通产生连续电流。开路电压试验时换流器以单阀间歇导通工况为主。特高压的第二阀组投入时,换流器在出口端由旁路开关短路时进行解锁,也会出现单阀间歇导通及两阀歇导通的电流不连续工况。结合实际工程的设备参数,特别是缓冲RC回路参数,并考虑阀控的补脉冲功能,对此进行分析研究,得出换流器单阀导通的等效电路。

The commissioning of HVDC transmission project is the final step of the construction.The analysis of electrical recording involves the theoretical problems of single valve triggered conduction and current discontinuity.The triggering of the thyristor of the HVDC transmission system adopts a single-pulse equal-interval triggering mode.During the unlocking period,the single-valve intermittent conduction of the converter occurs,and the function of complementary pulse is required to enable the two valves to conduct continuous current.In the open line voltage test,the converter is mainly operated by a single valve intermittent conduction.When the second valve group of the UHVDC is put into operation,the converter is unlocked when the outlet end is short-circuited by the bypass switch,and there is also a discontinuous current condition in which the single valve intermittent conduction and the two valve rest conduction.This paper combines the project equipment parameters,especially the buffer RC loop parameters,and considers the valve-controlled complementary pulse function,which is analyzed and studied,and the equivalent circuit of the single-valve conduction of the converter is obtained.