一种新的直流系统环网接地故障检测方法

在传统低频信号注入法的基础上提出了一种新的基于小波变换和分形理论的直流系统环网接地故障检测方法,引入分形理论中的凹凸度参数,利用凹凸度参数和分形维数唯一确定的二维平面上点的位置来识别不同情况下的环网接地故障。该方法弥补了低频信号注入法难以解决环网问题的缺陷,大量的仿真计算验证了该方法的有效性。

A New Method to Detect Grounding Fault of Looped Network in DC Power System

Based on traditional low frequency signal injection method, a new method to detect grounding fault in looped network of DC power system, which is based on wavelet transform and fractal theory is proposed. Leading in the concavo-convex parameter of fractal theory, the grounding fault in looped network under different conditions can be identified through the location of the point in two-dimensional surface that is exclusively determined by concavo-convex parameter and fractal dimension. The proposed method remedies the defect that it is hard for low frequency signal injection method to discriminate the fault in looped network. Simulations and calculations verify the effectiveness of the proposed method.