一起220kV终端线路单瞬故障特重失败行为分析

Analysis on a Special Reclosing Failure of Single-phase Transient Fault in a 220 kV Terminal Line

针对一起220 kV终端线路发生单相瞬时故障时保护装置未按特殊重合闸逻辑三跳三重的行为,通过对比不同装置厂家重合闸逻辑原理,论述了RCS-900系列线路保护装置闭锁重合闸条件与其他主流厂家的差异。然后,以典型单回终端线拓扑结构为例,详细推导单相故障时相间测量阻抗元件动作特性,并结合整定软件、录波结果进行验证。最后,对于当前终端线路特重方式下存在单相故障三跳不重的风险给出改进措施。

Aiming at the behavior of the relay protection,which failed to follow the special reclosing logic of three jumps and three repetitions,during a single-phase transient fault in a 220 kV terminal line,the reclosing logic principles of different device manufacturers are compared and the differences in the reclose locking conditions of the RCS-900 series line protection device compared to other mainstream manufacturers are discussed.Taking the typical topology structure of a single-loop terminal line as an example,the action characteristics of interphase impedance measuring elementunder single-phase fault are derived in detail and verified by the setting software and the fault recording.Finally,improvement measures are proposed for the risk of single-phase fault with three jumps and no reclosing under current special reclosing mode of terminal line.