传统的配电网故障分析方法已不能满足未来分布式发电系统的需求。为此,文中针对含分布式电源的配电网故障分析展开研究。将常见分布式电源节点划分为PQ节点、PI节点、PV节点和PQ(V)节点几种类型,并根据各节点类型的特点,提出了在故障分析中的处理方法。根据含分布式电源的三相不平衡弱环配电网的特点,在前推回推类方法的基础上,提出了一种含分布式电源的配电网三相故障计算的叠加方法。该方法既能用于辐射型网络,也能用于弱环网络。采用13节点算例对所述方法进行了测试,算例结果证明了该算法的可行性和有效性。
Traditional fault analysis of distribution networks cannot meet the requirement of distributed generation system (DGs). In order to solve this problem, different distributed generators are classified into four types: PQ node, PI node, PV node and PQ(V) node. According to the properties of four types of nodes, different methods are proposed to handle different types of nodes in fault calculation. Considering the asymmetric property of three-phase distribution networks with DGs, based on the forward and backward method, superposition principle with fault compensation circuit is used in fault analysis under an unified formula and similar iteration process as load flow calculation. The proposed approach can deal with both radial structure networks and weakly coupled circle networks. Test results of 13-node test system verified the feasibility and effectiveness of the proposed method.