一种基于双端电气量的故障测距方法研究

Study of a Method for Fault Location Based on Two-Terminal Electrical Quantities

分析了一种利用输电线路双端电气量进行精确故障定位的测距方法,该方法采用输电线路的分布参数模型,将线路故障看为正常运行状态和故障附加状态的叠加,基于等效序网,通过对称分量法求得故障附加状态下的各序故障分量,利用负序故障分量(三相对称故障采用正序故障分量)进行故障测距。在算法实现的关键环节分析了全波傅氏滤波算法。利用MATLAB仿真结果表明,该方法不严格要求线路两端数据同步采样,测距结果几乎不受线路负荷、故障点过渡电阻及故障合闸角等因素的影响,有较高的测距精度,具有较高的工程实用价值。

Analysis was made to a kind of distance measuring method to locate fault accurately using transmission line two-terminal electrical quantities.This method adopted distributed parameter model of transmission line,the fault state divided into normal operation and fault additional state.Based on transmission line＇s equivalent sequence network,the fault components of every sequence at the fault additional state were got through symmetrical component method.The negative sequence fault components（positive sequence fault components for three-phase symmetrical fault） were used to realize fault location.And full-wave Fourier algorithm was analyzed at the key tache.Simulation results in Matlab show that the data needed in the method is not strictly required synchronous sampling,and the fault location results are independent of the following factors,such as pre-fault line load,transition resistance and fault initial angle etc.The method can locate fault site precisely and has high practical value.