分布式光伏短路特性对配电网保护的影响研究

Study on Short-circuit Characteristics of Distributed Photovoltaic Power and Influence on Distribution Network Relay Protection

分布式光伏电源使配电网从单电源辐射型网络变为双向的多电源网络,电网潮流、系统故障时的短路电流均发生变化,传统的继电保护整定方案已经不能满足新型运行方式下的要求。建立光伏电站的等值模型并对其短路故障特性进行仿真分析。然后结合具体工程实例,研究不同的光伏接入容量对地区电网短路水平的影响。在上述仿真研究的基础上,进一步分析分布式光伏接入对配电网继电保护配置、整定计算方面的影响并提出改进措施。

Distributed photovoltaic power supply makes the distribution network change from a single power radiant network to a bi-directional multi-power network,and the short-circuit current in the case of power flow and system failure all change.The traditional relay protection setting scheme can no longer meet the requirements of the new operation mode.The equivalent model of photovoltaic power is established and its short-circuit fault characteristics are simulated and analyzed.The influence of different photovoltaic access capacity on short-circuit level of regional power grid is studied by combining with specific project examples.On the basis of the above simulation study,the influence of distributed photovoltaic access on relay protection configuration and setting calculation of distribution network is analyzed,and the improvement measures are proposed.