基于并联电抗器差模电流波形特征的三相自适应重合闸永久性故障识别  

Identification of Permanent Faults for Three-Phase Adaptive Reclosure Based on Waveform Characteristics of Differential Mode Currents in Shunt Reactors

作　　者：王庆庆[1] 王慧芳[1] 林达[1] 何奔腾[1] 

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027

出　　处：《电网技术》2015年第4期1127-1132,共6页Power System Technology

摘　　要：针对带并联电抗器的超高压输电线路,详细分析了发生两相或三相瞬时性及永久性故障时,故障相并联电抗器差模电流的特征:在线路两端三相跳闸以后,对于瞬时性故障,故障点熄弧以后,差模电流中只存在衰减周期分量,对于永久性故障,差模电流中只存在衰减直流分量。利用差模电流的这一特性可以提出适用于三相自适应重合闸中相间故障性质识别的新判据,该判据只需利用单端并联电抗器电流即可实现,并且可以判定熄弧时刻。大量ATP/EMTP电磁暂态仿真表明,该方法能够快速准确地识别故障性质,且基本不受故障位置、过渡电阻、采样频率、负荷电流、故障时刻、跳闸时刻、故障点熄弧时刻等因素的影响,且同时适用于单端和双端带并联电抗器的输电线路。When two-phase temporary or permanent fault or three-phase temporary or permanent fault occurred in UHVAC transmission line with shunt reactor, the characteristics of differential mode current of shunt reactor in fault phase is analyzed in detail. After the three-phase tripping out at both ends of the transmission line, for temporary fauk since the arc blowout at the fault point there is only the decaying periodic component in the differential mode current of shunt reactor, and for permanent fault there is only decaying DC component in the differential mode current of shunt reactor. Utilizing such a characteristic of the differential mode current of shunt reactor, it is possible to propose a new criterion that only suits to the identification of phase-to-phase fault characteristic during the three-phase adaptive reclosure, and this criterion can be realized by using the current in the shunt reactor current at one end and the moment of arc blowout can be judged as well. A lot of ATP/EMTP based simulation results show that using the proposed method the fault type can be distinguished rapidly and accurately, and basically the recognition is not affected by such factors as fault position, transition resistance, sampling frequency, load current, the moment when the fault occurred, the moment when the circuit breaker tripped out, and the moment of arc blowout at the fault point, besides, the proposed method is suitable for the transmission lines connected with shunt reactors at single end or both ends.

关 键 词：并联电抗器 三相自适应重合闸 瞬时性故障 永久性故障 差模电流 衰减周期分量 

分 类 号：TM721[电气工程—电力系统及自动化]