谐振接地配电网电弧接地故障暂态分析方法与辨识

谐振接地中压配电网常发生电弧接地故障,传统的故障暂态分析方法多将电弧电阻简化为线性过渡电阻后代入故障暂态等值电路求解,电弧非线性特征难以体现。针对该问题,适当简化电弧黑盒模型,提出一种适用于谐振接地配电网电弧接地故障的暂态分析方法,定量计算不同过渡电阻下电弧接地故障暂态电流的解析表达式,并根据电弧电压的奇频次谐波衰减特性,给出一种综合电弧电流与线路电压信息的稳定电弧接地故障辨识原理。通过仿真计算与现场实验数据验证了所提分析方法的有效性,为后续谐振接地配电网电弧接地故障保护的研究提供了理论依据。

Transient Analysis Method and Identification of Arc Grounding Faults in Petersen Coil Grounded Distribution Network

Arc grounding faults often occur in a Petersen coil grounded medium-voltage distribution network.The tradi?tional methods of fault transient analysis usually simplify the arc resistance to linear transition resistance,which is fur?ther substituted into the transient equivalent circuit under fault.As a result,the nonlinear characteristics of arc are diffi?cult to reflect.To solve this problem,the arc black box model is simplified appropriately,a transient analysis method which is suitable for arc grounding faults in the Petersen coil grounded distribution network is proposed,and the analyti?cal expression to quantitatively calculate the transient current under arc grounding faults with different transition resis?tances is given.In addition,based on the attenuation characteristics of odd frequency harmonics of arc voltage,the identification principle for arc grounding faults that combines arc current and line voltage information is proposed.The effectiveness of the novel method was verified by simulations and field test data,providing a theoretical basis for subse?quent researches on arc grounding faults protection of the Petersen coil grounded distribution network.