不同电压等级部分耦合输电线路故障测距

Fault Location for Partial Coupling Lines under Different Voltage Levels

针对两条输电线路电压等级不同、参数不对称的情况,首先利用采样值计算得到故障前后线路两端的电压、电流突变量,利用单回线的传统对称分量法解耦成序电压、序电流,从母线两端分别推算出耦合部分线路的两端电压、电流,然后利用新的六序分量法,将得到的电压、电流解耦成新的六序分量,最后采用输电线路双端测距方法,即利用从两端计算出故障点处电压相等的性质,获得故障测距公式,从而进行故障测距。仿真结果表明,该算法与故障点过渡电阻、故障类型以及系统的运行方式无关,可解决不同电压等级部分耦合输电线路的故障测距问题。

For the case of two transmission lines in different voltage levels and asymmetry parameter,partial uncoupling lines are first decoupled by new six-sequence component method and the fault location can be realized.The sampling voltage and current data of both ends of the transmission line can be used to obtain the faulted components,which can be decoupled into sequence voltage and sequence current by traditional symmetrical component method.Then the voltage and current of both ends of the partial uncoupling lines can be calculated from the bus bars.Secondly,the received data of voltage and current can be decoupled into the new six sequence component by new six-sequence component method.Finally,the fault location formula can be obtained based on that the voltages of fault point calculated by both ends are equivalent.Simulation results demonstrate that the proposed algorithm is nothing to do with the fault resistance,fault type and generation mode.Therefore,the problem of fault location for partial coupling lines under different voltage levels can be solved.