基于零序分量的阻抗法配电网故障定位技术

精准故障定位对提高配电网的安全性、可靠性有着重要意义。提出了一种基于零序分量的阻抗法定位技术。依据线电压对称性及零序电压幅值判断是否发生单相接地故障，再利用安装在母线处及线路末端的同步相量测量单元获取线路发生单相接地故障后的稳态零序信号。在此基础上，根据线路两端零序电压、母线侧零序电流及线路零序参数建立各区段发生单相接地故障时的测距方程，以区段线路长度为限制排除伪根、确定真实根，通过遍历系统各区段可同时实现区段定位及故障测距。在EMTP/ATP仿真软件中搭建10 kV配电网。结果表明，所提方法在混合线路、多分支线路等多种配电网结构下都能保持较高精度，且测距精度不受接地电阻和故障相角的影响。

Impedance fault location technology for a distribution network based on a zero-sequence component

Accurate fault location is of great significance in improving the safety and reliability of a distribution network. An impedance fault location technology based on a zero-sequence component is proposed. First, a single-phase ground fault can be judged according to the symmetry of line voltages and the amplitude of the zero-sequence voltage. Then the PMU device installed at the bus and the end of the line is used to obtain the steady-state zero-sequence signal after a fault occurs. Then, according to the zero-sequence voltage at both ends of the line, the current at the bus side and the parameters of the line, the fault location equation in each section is established. The pseudo root and real root are distinguished according to the limit of the length of the section. By traversing each section of the system, section and fault location can be realized at the same time. A 10 kV distribution network is built in EMTP/ATP simulation software. The results show that the method can maintain high accuracy under various distribution network structures such as hybrid lines and multi-branch lines, and the ranging accuracy is not affected by the grounding resistance and fault phase angle.