高压直流断路器在张北柔性直流电网中的应用

Application of HVDC Circuit Breaker in Zhangbei Flexible DC Power Grid

高压直流断路器是柔性直流换流站构成直流电网的核心设备,但±500 kV电压等级的高压直流断路器尚无应用经验。为了验证±500 kV高压直流断路器在实际应用中的开断特性,介绍了机械式、耦合负压式、混合式3种不同技术路线的高压直流断路器的拓扑结构,在张北柔性直流电网中通过现场实际短路接地故障,验证了±500 kV高压直流断路器能够在3 ms内可靠切断故障电流,最后对3种不同技术路线的高压直流断路器工作特性进行对比分析,指出了不同技术路线的高压直流断路器在分合闸过程中存在的问题,为大容量高压直流断路器的研制与应用提供一定参考。

HVDC circuit breaker is the core equipment of flexible DC converter station to form DC power grid,but there is no application experience of±500 kV HVDC circuit breaker of voltage-grade.In order to verify the on-off characteristics of±500 kV HVDC circuit breaker in practical application,it introduces the topological structures of HVDC circuit breakers with three different technical routes like mechanical type,coupled negative pressure type and hybrid type.In Zhangbei flexible DC power grid,through the practical short-circuit grounding fault on site,it verifies that the±500 kV HVDC circuit breaker can reliably cut off the fault current within 3 ms.Finally,the operating characteristics of the HVDC circuit breaker of three different technical routes are compared and analyzed,and the problems existing in the process of switching and closing of the HVDC circuit breaker of different technical routes are pointed out,which provide reference for the development and application of the high-capacity HVDC circuit breaker.