静态阻塞滤波器的电抗器匝间故障及其保护的分析

摘要

Aiming at the reactor inter-turn short circuit fault of SBF(Static Blocking Filter),its steady-state equivalent circuit is deduced based on the superposition principle and symmetrical component method and the influences of fault extent on the SBF current,reactor current,capacitor current and sequential component currents are calculated.Calculative results show that the current of faulty phase will be very big if the equivalent impedance of SBF is capacitive and the equivalent reactance of power grid is mostly compensated.The principles of over-current protection and LC detuning protection are introduced.An actual case of inter-turn short circuit fault is analyzed,verifying the correctness of the calculative results.The proposed calculation method and analytical results help to understand the characteristics of reactor inter-turn fault and improve the design and application of SBF protection system.%针对静态阻塞滤波器(SBF)内部电抗器匝间故障,采用叠加原理和对称分量法推导了稳态等值电路,计算了不同程度的故障对SBF电流、电抗器电流、电容器电流和各序分量电流的影响.计算结果表明当SBF等值电抗呈容性并且高比率补偿系统等值电抗时,故障相会出现非常大的电流.介绍了过流保护和LC失谐保护原理.分析了实际发生的匝间故障案例,结果表明了计算结果的正确性.所提计算方法与分析结果有助于理解SBF的故障特征、SBF保护系统的设计及应用的改进.