基于多重分形降趋波动分析法的谐振接地系统故障选线新判据

A new criterion of fault line selection in resonant grounding system based on multifractal detrended flucuation analysis

配电网系统中单相接地故障快速准确选线对电网安全运行具有重要意义。为克服传统故障选线方法中抗噪声干扰能力差、受消弧线圈补偿度等因素的影响引起选线结果不准确的问题,提出了基于多重分形降趋波动分析法(MFDFA)的谐振接地系统故障选线新判据。利用界值比ζ来描述各馈线零序电流分形参数曲线H(q)的分布特性,根据其数值差异进行故障选线。仿真结果表明该判据具有无需滤波、抗噪能力强、计算速度快的优点,克服了消弧线圈和故障条件等因素对故障选线的影响。

The fast and accurate fault line selection of single phase to earth fault in distribution network system is of great significance to the safe operation of power network. To overcome the problem of inaccurate result of traditional fault line selection method which is caused by poor ability to resist noise and influence of the compensation degree of arc suppression coil,a new criterion of fault line selection in resonant grounding system based on multifractal detrended flucuation analysis（ MFDFA） is presented in this paper. Using the boundary value ratio ζ to describe distribution features of the zero sequence current fractal parameters feeder curve H（ q）,the fault line selection based on the numerical difference. Simulation results show that the proposed criterion has the advantages of no filtering,strong antinoise ability,computing speed and overcome the arc suppression coil on the influence of fault line selection and fault conditions.