基于暂态零序电流的含光伏电源配电网单相故障定位方法

Single-Phase Fault Location Method of Photovoltaic Power Distribution Network Based on Transient Zero-Sequence Current

针对分布式光伏电源接入配电网使得传统配电网继电保护存在可靠性、灵敏性降低的问题,提出了一种考虑母线多分支情况下应用偏度系数来衡量暂态零序电流极性的分布式故障定位方法。分析了分布式电源接入的配电网发生单相接地故障时零序电流的分布特征,发现故障时刻故障区段两端暂态零序电流极性相同,非故障区段两端暂态零序电流极性相反,引入偏度系数来衡量暂态零序电流的极性,实现分布式故障定位。仿真结果表明,该方法能够适用于含分布式光伏电源配电网的故障定位,且在不同的故障条件下具有较强的适用性。

The connection of distributed photovoltaic power to distribution network may cause the decrease of the reliability and sensitivity of traditional distribution network relay protection. To solve this problem, a distributed fault location method based on skewness coefficient is proposed to measure the polarity of transient zero-sequence current considering the multi-branch bus. The distribution characteristics of zero-sequence current when single-phase grounding fault occurs in the distribution network connected with distributed generation are analyzed. Thus, the characteristics of the same polarity of transient zero-sequence current at both ends of the fault section at fault time and the opposite polarity of transient zero-sequence current at both ends of the non-fault section are further obtained. The skewness coefficient is introduced to measure the polarity of transient zero-sequence current and realize the distributed fault location. The simulation results show that the method can be applied to the fault location of distribution network with distributed photovoltaic power supply, and has strong applicability under different fault conditions.