基于负序电流幅值的含光伏配电网两相短路故障方向判据  

Direction Criterion for Phase-to-phase Short-circuit Faults in Distribution Networks with Photovoltaic Based on Negative-sequence Current Amplitude

作　　者：牟锐 何佳伟[1] 李斌[1] 周博昊 张永伍[2] 黄家凯 MU Rui;HE Jiawei;LI Bin;ZHOU Bohao;ZHANG Yongwu;HUANG Jiakai(Key Laboratory of Smart Grid of Ministry of Education(Tianjin University),Tianjin 300072,China;State Grid Tianjin Electric Power Company,Tianjin 300010,China)

机构地区：[1]智能电网教育部重点实验室(天津大学),天津市300072 [2]国网天津市电力公司,天津市300010

出　　处：《电力系统自动化》2024年第19期148-161,共14页Automation of Electric Power Systems

基　　金：国家电网公司科技项目(5100-202212375A-2-0-ZN)。

摘　　要：当分布式光伏接入的配电网发生故障时,传统功率方向元件在光伏低电压穿越以及负序电流抑制控制策略的影响下动作性能降低。文中首先分析了典型两馈线配电网保护正、反向区域发生两相短路故障时负序电流及负序电压的分布特性。在此基础上,提出一种适用于分布式光伏接入的配电网两相短路故障方向判别方法,利用负序电流幅值实现两相短路故障方向的可靠判别,并引入负序电压判据,实现三相短路故障下的可靠闭锁。进一步地,提出了判据动作定值的理论计算方法,并定量分析了光伏接入容量对所提方向判据灵敏性的影响及其最大耐受过渡电阻能力。最后,基于PSCAD/EMTDC平台进行了算例仿真,结果验证了所提判据的有效性。When faults occur in the distribution network with the integration of distributed photovoltaic,the performance of traditional power direction element decreases under the influence of photovoltaic low voltage ride-through and negative-sequence current suppression control strategies.Firstly,this paper analyzes the distribution characteristics of negative-sequence current and negative-sequence voltage when a phase-to-phase short-circuit fault occurs in the forward and backward areas of protection in a typical two-feeder distribution network.On this basis,a method for identifying the direction of phase-to-phase short-circuit faults in distribution networks with the access of distributed photovoltaic is proposed.The reliable identification of the direction of phase-tophase short-circuit faults is achieved by using the amplitude of negative-sequence current,and the negative-sequence voltage criterion is introduced to achieve reliable blocking under three-phase short-circuit faults.Furthermore,a theoretical calculation method for the action setting values of the criterion is proposed,and the influence of photovoltaic integration capacity on the sensitivity of the proposed directional criterion and its maximum transition resistance tolerance are quantitatively analyzed.Finally,case simulations are conducted based on the PSCAD/EMTDC platform,and the results verify the effectiveness of the proposed criteria.

关 键 词：分布式光伏 配电网 方向判据 负序电流 负序电压闭锁 

分 类 号：TM615[电气工程—电力系统及自动化]