基于零序电流近似熵的配电网故障定位研究

Research on Fault Location of Neutral Ungrounded System Based on Approximate Entropy of Zero Sequence Current

针对10 kV配电网线路发生单相接地故障时产生的暂态零序电流,提出了一种近似熵算法,对接地故障区间进行定位。首先,设计暂态零序电流的近似熵值计算方法,求取线路中各相邻测点熵值之比;其次,设计各区段故障临界值判定方法,由此比较该值与比值来锁定故障发生位置;最后,通过MATLAB/Simulink对正常以及暂态过程进行仿真,从仿真模型角度佐证了该方法对于配电网单相接地故障的可行性并搭建硬件实物平台实现其故障定位的功能。

Aiming at the transient zero-sequence current generated when a single-phase ground fault occurs in a 10kV distribution network line,an approximate entropy algorithm is proposed to locate the ground fault interval.Firstly,the approximate entropy calculation method of transient zero-sequence current is designed,and the ratio of the entropy value of each adjacent measurement point in the line is obtained.Secondly,the fault threshold determination method of each section is designed,and the value and ratio are compared to lock the fault location.Finally,the normal and transient processes are simulated by MATLAB/Simulink,which proves the feasibility of the method for singlephase ground faults in distribution network from the perspective of simulation model,and builds a hardware physical platform to realize its fault location function.