超高压线路保护零序电流变化量启动判据研究

Research of Starting Criteria on Zero-sequence Current Variation of UHV Line Protection

提出采用零序电流变化量、相电流变化量比较为基础的零序电流变化量启动判据,在系统负荷较大波动或纯振荡下能可靠闭锁启动,同时在振荡过程中发生故障能可靠开放,分析了零序电流变化量启动判据在单相、两相经较大过渡电阻接地动作机理,并在PSCAD/EMTDC建立仿真模型,仿真数据表明,该判据能提高零序启动元件的灵敏度和快速性。

This paper proposes a starting criteria of zero-sequence current variation based on comparing zero-sequence current variation with phase-current variation,it can blocking start when system load has larger fluctuation or oscillation and can opening in the process of oscillation after developing a fault. Larger fault resistance group operation mechanism for starting criteria of zero-sequence current variation in one-phase and two- phase systems are analyzed,simulation model is set up by using PSCAD / EMTDC. Results demonstrate that this criteria can increase sensitivity and rapidity of zero-sequence starting component.