含高比例分布式光伏的中低压配电网继电保护方法研究

Research on Relay Protection Method of Medium and Low Voltage Distribution Network with High Proportion Distributed Photovoltaic

分布式光伏的接入导致中低压配电网原有的继电保护可靠性降低或失效,因此在分析分布式光伏对故障特性影响机理的基础上,提出适用于含高比例分布式光伏的配电网继电保护新方案。建立了含高比例分布式光伏配电网的等效模型,分析了故障后电气分量分布特性和分布式光伏容量、电气位置对故障分量的影响规律,并提出保护配置和保护判据整定方法。通过MATLAB仿真平台对三相短路故障工况进行了仿真测试,结果表明所提出的保护方法能准确可靠切除故障,具有良好的选择性和灵敏性。

Distributed photovoltaic access leads to the reduction or failure of the original relay protection reliability of medium and low voltage distribution network.Therefore,based on the analysis of the influence mechanism of distributed photovoltaics on fault characteristics,a novel scheme for relay protection of distribution networks with high proportion of distributed photovoltaics is proposed.The equivalent model of distributed photovoltaic distribution network with high proportion is established,the distribution characteristics of electrical components after fault,and the influence law of distributed photovoltaic capacity and electrical location on fault components are analyzed.The protection configuration and setting method of protection criterion are proposed.The three-phase short-circuit fault condition is simulated and tested through the MATLAB simulation platform.The results show that the proposed protection method can accurately and reliably remove the fault,and has good selectivity and sensitivity.