Applied research on single-phase grounding fault line selection based on compensation characteristics of arc suppression coil

In distribution network systems where the neutral point is grounded through arc suppression coils, the existing accuracy of the single-phase grounding fault line selection method requires enhancement due to the transient characteristics arising from arc suppression coil compensation and potential polarity errors in zero-sequence current transformers. The singlephase grounding fault line selection method based on the compensation characteristics of arc suppression coils holds the potential to theoretically improve the accuracy of selecting single-phase grounding fault lines. This paper delves into the practical application of this method within distribution network systems grounded through the neutral point via arc suppression coil compensation. An analysis is conducted on the characteristics of actual single-phase grounding fault lines under both overcompensation and under-compensation scenarios, as well as the characteristics of fault lines under the influence of polarity errors in zero-sequence current transformers at the line outlet. The results of the analysis demonstrate that the single-phase grounding fault line selection method, based on the compensation characteristics of arc suppression coils, can effectively overcome the impact of both the transient characteristics associated with arc suppression coil compensation and the errors in polarity of zero-sequence current transformers.