分布式发电系统故障定位新算法

A new fault location algorithm for distributed generation system

分布式电源(Distributed Generation,DG)接入配电网后,配电网由单电源辐射状网络变成了分布电源供电的复杂网络,保护的运行环境发生了深刻变化。根据分布式发电系统结构和特点,提出一种基于分布决策的故障定位新算法,进行网络划分形成智能电子装置(IED)的关联区域,利用关联区域边界节点信息完成故障初步定位,再根据故障关联区域的节点连接关系,利用各区段两端节点信息精确定位故障。算法采用静态区域划分,划分结果可动态修整,降低了实时性要求且对IED信息缺失及DG投切造成的电网结构变化具有一定的适应性;故障一次和二次定位原理清晰,信息和计算量小。通过对算法的算例分析,验证了算法的正确性。

The connection of DG makes distribution network change from single-power radiant to a complicated one with distributed power,thus operation environment of protection changes profoundly.According to the structure and feature of distributed generation system,this paper proposes a new distributed decision-based fault location algorithm.Firstly,associated region is determined on the basis of network segmentation.Then by using the information at the boundary node of associated region,preliminary location for fault is implemented.Finally,based on the node connectivity of fault-related region,fault location with high precision is realized by the information at the two ending nodes of each section.For using static region division,which can be dynamically dressed,in this algorithm,it reduces restriction for real-time performance and has certain adaptability for scarcity of IED information and changes of power network structure resulting from switching of DG.Additionally,both first and secondary fault location are clear in principle and have features of little information and low computational complexity.Through a case analysis,the validity of this algorithm is verified.