补偿电网单相接地故障选线

由于消弧线圈补偿电流的加入，使故障馈出线的零序测量电流的相位和幅值发生变化，更增加了小电流接地选线的难度。在详细分析补偿电网零序测量电流分布的基础上，将消弧线圈补偿电流融入小电流接地选线计算和判断中，提出一种新的、针对补偿电网和基于单相接地故障工频稳态量分析的小电流接地选线算法。EMTP仿真分析显示了该算法具有较高的保护裕度。初步挂网运行试验也证明了该算法选线准确性较高。

Detecting single-phase-to-ground fault feeder in Compensation Networks

The compensation current of the arc suppressing coil makes the phase angle and amplitude of the zero sequence measurement current of the earthed fault feeder vary greatly,and thus increases the difficulty of the detecting single-phase-to-ground fault feeder even more.On the basis of detailed analysis of the zero sequence measurement current distribution in the arc suppressing coil earthed power system,a new detecting one-phase-to-ground fault feeder algorithm is proposed.The algorithm adds the arc suppressing coil compensation current to the zero sequence current of every feeder in steady-state computations in power systems.The EMTP simulations and analyses show the algorithm proposed has effectively reinforced the protecting abundant degree.The operation results of actual power systems indicate the device based on the algorithm has a high accuracy in detecting the fault feeder in compensation networks.