基于并联定值电阻及稳态频域实部突变的缆线混合故障选线

Hybrid fault line selection based on parallel constant resistance and real part mutation in steady frequency domain

经消弧线圈接地系统投切并联定值电阻会改变电力系统的拓扑结构,因此可以为故障选线提供更多信息.基于此提出了基于并联定值电阻及稳态频域实部突变的缆线混合故障选线.首先分析了定值电阻投切前后稳态信息的差异,发现在投切定值电阻前后故障线路零序复电流实部变化明显大于健全线路,因此针对此差异,计算投入定值电阻前后零序复电流实部变换从而实现故障选线.大量仿真结果证明,该方法受不同故障条件影响较小,可靠性高,抗干扰性强.

The topological structure of power system can be changed by switching on and off the parallel constant resistance through arc-suppression coil grounding system,so it can provide more information for fault line selec⁃tion.In this paper,a hybrid fault line selection method based on parallel constant resistance and real part mutation in steady frequency domain is proposed.In this paper,the difference of steady-state information before and after constant resistance switching is analyzed,and it is found that the change of the real part of the zero sequence com⁃plex current of the fault line before and after constant resistance switching is significantly greater than that of the sound line.Therefore,in view of this difference,the real part of the zero sequence complex current before and after constant resistance switching is calculated to achieve fault line selection.A lot of simulation results show that this method is less affected by different fault conditions,has high reliability and strong anti-interference.