基于相量测量的配电网单相断线接地识别方法

Identification of Single-line-to-ground Faults with Line-break in Distribution Network Based on Phase Measurement

在配电网中,带有断线的单相接地故障发生得越来越频繁,经常造成重大安全事故。由于谐振接地系统和非接地系统的电源侧电气特性相同,很难区分谐振接地系统和非接地系统中的单相断线接地故障和单相接地故障。本文提出了一种区分单相断线接地故障和单相接地故障的方法,首先分析两种故障的电源侧和负荷侧电压特性,利用相位测量单元作为测量设备,选择负荷侧故障相电压和非故障相电压之间的相位差作为识别标准,然后分析了配电网中的运行条件和外部设备对识别方法的影响,计算了由其引起的相位误差,并修正识别方法,最后通过仿真验证了所提方法的有效性和鲁棒性。

In the distribution network,single-line-to-ground faults with line-break occur more and more frequently,often causing major security incidents.Due to the same electrical characteristics on the power side of resonant grounding systems and non-grounded systems,it is difficult to distinguish between single-line-to-ground faults with line-break and single-line-to-ground faults in resonant grounding systems and non-grounding systems.A method is proposed in this paper to distinguish between single-line-to-ground faults with line-break and single-line-to-ground faults.Firstly,the voltage characteristics of the power supply side and the load side of the two faults are analyzed,the phase measurement unit is used as the measurement device,and the phase difference between the fault phase voltage and the non-fault phase voltage on the load side is selected as the identification standard.Then,the influence of operation conditions and external devices in distribution network on the identification method is analyzed,by which the phase error caused is calculated to correct the identification method.Finally,the effectiveness and robustness of the proposed method are verified by simulation.