带并联电抗器的超高压输电线路自适应重合闸新判据

A New Criterion for Adaptive Single Pole Auto-reclosure of EHV Transmission Lines with Shunt Reactor Compensation

对带并联电抗器线路发生瞬时性单相接地故障时跳开相的恢复电压特征进行了分析,应用拉普拉斯变换对恢复电压中的各种暂态分量进行了定量求解,从原理上揭示了恢复电压中衰减周期分量的产生原因。通过瞬时性故障与永久性故障时故障相端电压波形的对比,提出了识别永久性单相接地故障的跳开相端电压衰减周期分量幅值判据,并给出一种从跳开相端电压中提取低频衰减周期分量幅值的实用方法,该方法计算简单,判定迅速准确,且不受过渡电阻影响,可有效应用于带并联电抗器的超高压输电线路单相自适应重合闸故障性质的识别及重合时刻的选择。

Based on the research on characteristics of the recovery voltage of the opened phase when a transient single phase fault occurs on a shunt reactor compensated transmission line, quantitative analysis is performed on the transient components of the recovery voltage by s-domain analysis. The cause of the decaying periodic component of the recovery voltage is revealed. Based on the comparison between the wave form of the terminal voltage of the faulted phase of a transient fault and that of a permanent fault, a criterion for identifying the magnitude of the decaying periodic component of the terminal voltage on the opened phase caused by the permanent single-phase fault is proposed and a practical method for extracting the magnitude is presented. The method is simple and fast, and not subject to the influence of transition resistance. It can be applied to fault nature identification in an adaptive single pole auto-reclosure scheme for transmission lines with shunt reactor compensation and selection of proper reclosure time instance.