基于金属护层模型参数辨识的电缆单相故障单端测距方法

电缆大部分故障均与金属护层相关,仅考虑缆芯电气结构参数的模型无法实现护层相关的故障测距。为解决配电网电缆单相故障测距困难的问题,提出了基于金属护层模型参数辨识的电缆单相故障单端测距方法。以配电网单相故障零模等效网络作为辨识模型,将故障距离、过渡电阻、对地电容作为模型的未知参数,利用电缆单相接地故障后缆芯和护层中的暂态信息并结合故障状态网络和零模等效模型,建立时域测距方程作为参数辨识目标函数,用最小二乘算法进行最优参数求解,得到故障距离。ATP-EMTP仿真结果验证了所提方法的有效性,且测距精度高。

A single terminal fault location method for single phase fault of cable based on parameter identification of metal sheath model

Most of the cable faults are related to metal sheath, only considering the structural parameters of the guide core electrical model cannot realize the fault location of the protective layer. In order to solve the problem of distribution network single-phase cable fault location difficulties, a single terminal fault location method for cable single phase fault based on metal sheath model parameter identification is proposed. This paper first takes the single-phase distribution network fault zero mold equivalent network as the identification model, and fault distance, fault resistance, and capacitance to ground as the unknown parameters of the model, then uses the transient information cable after the single-phase grounding fault cable core and sheath and combines the fault state network and zero mold equivalent model to establish the time-domain ranging equation as a parameter the identification of the objective function, finally applies the least-square algorithm to solve the optimal parameters, obtaining the fault distance. ATP-EMTP simulation results verify the effectiveness of the proposed method, and the ranging accuracy is high. This work is supported by National Natural Science Foundation of China (No. 51477147).