基于故障相电压功率谱的高压输电线路单相自适应重合闸

分析了带并联电抗器的高压输电线路发生单相接地故障时故障相恢复电压的特性，结果表明：单相瞬时性故障时的恢复电压由自由分量与工频分量叠加而成，其功率谱有2条谱线；而单相永久性故障时的恢复电压中只包含工频分量，其功率谱有1条谱线。文章据此提出一种基于输电线路故障相电压功率谱的单相接地故障识别方法，该方法利用故障相电压功率谱中谱线在基频附近的分布状态来区分瞬时性和永久性故障。该判据不需要高频参量，易于整定和实现。针对超高压输电线路单相接地故障的仿真结果验证了判据的准确性和可行性。

Single-Phase Adaptive Reclosure for EHV/UHV Transmission Line Based on Power Spectrum of Faulty Phase Voltage

The recovery voltage characteristic of faulty phase under single-phase earth fault occurred in extra high voltage/ultra high voltage (EHV/UHV) transmission lines with shunt reactors is analyzed. Analysis result shows that the recovery voltage of single-phase temporary fault is superposed by free component and power frequency component, and its power spectrum possesses two spectral lines; yet the recovery voltage of single-phase permanent fault contains power frequency component only, and its power spectrum possesses one spectral line. On this basis, an identification method of single-phase earth fault based on power spectrum of faulty phase voltage is proposed, which distinguishes temporary fault from permanent fault by the distribution of spectral line in the power spectrum of faulty phase voltage near fundamental frequency. This criterion need not high frequency parameters, so the proposed method is easy to set and implemented. Simulation results of single-phase earth fault occurred in UHV transmission line validate the accuracy and feasibility of the proposed criterion.