高压输电线路的短路故障多伴随有电弧,针对目前众多故障定位算法中没有考虑过渡电阻的非线性特性的现状,提出了一种使用单端电气量进行故障测距的算法,该算法首先将耦合双回线解耦为同向量和反向量,根据反向量序网两端电压为零的特点,仅利用单侧电流推导故障点处的电压和电流,然后根据电弧故障电压、电流的转移特性构造测距方程,并利用最小二乘方法求解,实现故障测距。该算法使用了最小二乘方法得到故障距离,不需要输入对端系统等值阻抗,从理论上保证了该算法具有较高的测距精度。该算法理论分析简单,电磁暂态程序ATP仿真结果表明该测距算法有效、精度高。
The short- circuit faults of high voltage transmission lines always generate electrical arc. With consideration of the nonlinear character of transient resistance,a fault location algorithm based on post- fault voltage and current measured at single terminal is presented. It decouples two parallel transmission lines as positive direction network and negative direction network. For the voltages at two terminals of negative network are zero,the voltage and current at the fault point are calculated by Single terminal current. The fault location equation is formed according to the transfer characteristics of arc voltage and current,and solved by the least square method. The features of the proposed algorithm are as following:the fault location is calculated by the least square method;it is independent of source impedance,which ensures its high accuracy. It is easy to be understood theoretically and the results of ATP simulation confirm its effectiveness and accuracy.