针对现有输电线路中采用固定时限的单相重合闸存在盲目重合于永久性故障的问题,研究了一种重合前可靠识别严重永久性故障不重合的重合闸新方案。结合带并联电抗器的超/特高压线路的提高供电可靠性和减小重合过电压的要求,提出了以单相故障可靠选相为基础、严重永久性故障可靠不重合、瞬时性故障可靠重合的单相重合闸新方案。利用测量精度高的并联电抗器电流量实现单相重合闸的故障识别,采用跳开相并联电抗器电流拍频特性和线路电容参数识别2种方法相结合的单相故障性质识别判据,保证了严重永久性故障的可靠判别和瞬时性故障时最大的重合机会。大量仿真数据验证了所提单相重合闸方案的正确性和有效性,能够兼顾输电线路单相重合闸快速性和成功率。
A reclose scheme is proposed for EHV/UHV transmission lines with shunt reactors,which detects the serious permanent faults based on reliable single faulty phase identification and blocks reclosing.It applies the currents accurately measured by the shunt reactors and adopts the criterion combining the oscillation characteristic of open-phase current and the line capacitance parameter to identify the faulty phase.Simulative data show both the quickness and success rate of transmission lines sing-phase reclose are ensured,which proves its validity and effectiveness.