超多断口500kV快速隔离开关均压设计及试验

Voltage-sharing Design and Test of 500 kV Fast Isolation Switch with Multi-break

快速隔离开关作为混合式直流断路器的关键器件之一,其分断速度、稳定性等参数直接关系到断路器的整机性能。迄今为止,为满足在2 ms内建立绝缘能力的快速隔离需求,高压断路器用隔离开关普遍采用多断口方案,断口数目甚至多达8~12个,且其结构复杂,对多断口均压提出更高的要求。该文分析了500 kV混合式直流断路器用快速隔离开关的需求,结合10断口隔离开关的结构布局,提出了一套基于场路耦合的超多断口隔离开关均压设计方法,同时对断口均压进行优化,并完成了相关试验验证。该方案提高了隔离开关性能、减少了断口数目,并提高了整机运行的可靠性。

The breaking speed and stability of fast disconnector,which is one of the key components of hybrid direct current(DC)circuit breaker,are directly related to the performance of whole circuit breaker.Up to now,in order to meet the requirements of fast isolation,the multi-break scheme is generally adopted for an isolator for high voltage circuit breaker,the isolator has 8~12 breaks,and its structure is complex,which proposes higher requirements for multi-break voltage sharing.Consequently,we analyzed the requirements of fast disconnector for 500 kV hybrid DC circuit breaker.Combining with the structure layout of 10-break disconnector,we proposed a method of voltage sharing based on field-circuit coupling,which optimizes the voltage sharing of the fast isolation switch and completes the relevant test verification.It improves the performance disconnector,decreases the number of breaks and improves the reliability of the whole machine.