中性点经消弧线圈接地配电网弧光高阻接地故障非线性建模及故障解析分析

Nonlinear Modeling and Analytical Analysis of Arc High Resistance Grounding Fault in Distribution Network With Neutral Grounding via Arc Suppression Coil

中性点经消弧线圈接地配电网弧光高阻接地故障是目前配电网单相接地故障选线、检测的难点,故障点长时间存在极易引发山火、人身触电等恶性事故。现有研究未考虑零输入响应对故障状态方程的影响,尚无考虑电弧非线性的故障状态方程解析求解方法。针对该问题,该文建立零输入+零状态的完备非线性弧光高阻接地故障模型,采用电弧分段线性化,求解给出欠阻尼和过阻尼两种情况下故障零模电压、零模电流的解析表达式。算例仿真验证了非线性故障状态方程解析解的正确性,为后续的故障检测算法研究提供了理论基础。

It is difficult to detect the occurrence of arc high resistance grounding fault in distribution network with neutral point grounding through arc suppression coil in the application of single-phase grounding fault line selection or detection. The influence of zero input response on the fault state equation is not considered in the existing research, and the analytical solution method of fault state equation considering arc nonlinearity is not available yet. In order to solve this problem,a complete nonlinear arc high resistance grounding fault model with zero input and zero state was established in this paper. The arc piecewise linearization was used to solve the problem. The analytical expressions of zero mode voltage and zero mode current of fault under damping and over damping were proposed in paper. The correctness of the analytical solution of the nonlinear fault state equation was verified by numerical simulations, which provides a theoretical basis for the follow-up fault detection algorithm research.