提出一种基于模型识别的带并联电抗器输电线路三相重合闸永久性故障判别方法。该方法以选相结果为基础,以瞬时性故障π形模型为识别模型,将并联电抗器电流作为已知量,求取本端及对端线模电压和电容电流的线模分量,进而求解两端并联电抗器电流和电容电流线模分量之和。瞬时性故障时,故障模型与识别模型一致,求解值等于0;永久性故障时,故障模型与识别模型不一致,求解值不等于0。据此可以判别是否为永久性故障。电磁暂态分析程序(EMTP)仿真表明,该方法能够有效识别永久性故障,可靠实现带并联电抗器输电线路的三相自适应重合闸。
A novel permanent fault discrimination method for three-phase auto-reclosing of transmission lines with shunt reactors is proposed. The method takes phase selection results as basis and considers the transient fault model as the reference. It takes currents of shunt reactors as known quantities and calculates the aerial modal component of capacitive currents and voltages of both terminals. The formula is further established for summing the currents of shunt reactors and aerial modal component of capacitive currents of both terminals. In case of a transient fault,the result of the formula is zero because the actual fault model is consistent with the reference. But in case of a permanent fault,the result of the formula is non-zero because the actual fault model is inconsistent with the reference. EMTP simulation results show that the proposed method can reliably and effectively distinguish permanent faults from transient faults and apply to three-phase adaptive reclosure scheme on transmission lines with shunt reactors.