阶跃响应法在浮地交流系统绝缘故障定位中的应用初探

Application of step-response method in the insulation fault location of earth-floating AC system

针对交流系统绝缘故障定位现有方法存在的问题,提出了一种新的解决方案———阶跃响应法。通过对阶跃信号注入电网后的负载支路漏电流及其传感器感应电流的理论分析,得到了支路阻性电流与容性电流在时域上分离,而与电网工频信号在频域分离,从而易于提取的结论。并通过试验验证。

Power network ground capacitance can influence the correctness of fault location, which is hard to be overcome with existing fault-location method. To solve this problem, a new method—step-response method is developed and presented in this paper. The method can achieve separation between the characteristic value reflecting the ground resistance and the value reflecting the ground capacitance in time domain. Moreover, the characteristic value is also separated from the power-frequency signals of power network in frequency domain and can be picked up easily. The paper reaches the conclusions based on both theoretical analysis and experimental research.