采用同步变化量的超高压线路保护启动判据研究Research on the Criterion of UHV Line Protection Based on Synchronous Variation
金超杰,陈晓明,李德利
JIN Chaojie,CHEN Xiaoming,LI Deli
摘要(Abstract)：
超高压线路保护在运行中受负荷波动影响,负荷不对称的线路在正常运行时,都存在较大零序电流,为防止频繁启动不得不提高启动值,从而降低了启动元件的灵敏度,导致现有的零序电流判据对经高阻接地的故障无法灵敏判别,不能满足超高压线路保护对启动元件快速性的要求。提出一种采用线电压、同相间电流同步变化量开放的相间启动判据和零序电流、相电流同步变化量比较方式的零序启动判据。通过PSCAD/EMTDC仿真表明,如果使用同步变化量的启动判据,保护的灵敏度、快速性和可靠性均有一定程度的提高。
UHV line protection devices are easily affected by load fluctuation. Lines with asymmetric load carry larger zero-sequence current in normal operation. So the starting value has to be increased to prevent frequent starts. Therefore, sensitivity of starting components is reduced and faults due to high resistance grounding cannot be sensitively determined by existing criterion of zero-sequence current, which fails to meet the requirement of UHV lines on rapidity of starting component. This paper puts forward a new starting algorithm,in which interphase startup criterion is based on phase-to-phase synchronous current variation value with synchronous current variation value abrupt change, zero sequence startup criterion is based on the mutations current synchronous variation value of zero sequence compare with the abrupt change of phase current value. It is proved by PSCAD/EMTDC simulation that starting criterion based on synchronous variation can improve sensitivity, rapidity and reliability of UHV line protection devices.
关键词(KeyWords)：
高压输电线路;保护;启动元件;变化量
HV transmission line;protection;starting component;variation
基金项目(Foundation):
作者(Author):
金超杰,陈晓明,李德利
JIN Chaojie,CHEN Xiaoming,LI Deli
DOI: 10.19585/j.zjdl.2015.01.001
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