分布式发电(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,传统的故障区段定位算法不再适用。文中提出了一种基于故障电流的新型定位算法,首先基于DG渗透条件下配电网结构的搜索树,对故障通道进行判断搜索;然后利用搜索得到的与故障呈强相关状态的节点构建故障信息矩阵,利用基尔霍夫定律及相位比较原理执行相应的矩阵算法,进行故障区段的准确定位。该算法对网络初始结构及DG投切的变化具有一定的适应性;同时采用序电流加权和的综合电流量作为故障电流判据,提高了算法的灵敏度。通过对该算法的算例分析,验证了算法的正确性。
The conventional automation fault section locating, which has traditionally been designed assuming the system to be radial is no longer suitable for the system with distributed generation (DG). A new locating algorithm based on fault current signals is proposed in the paper, which first, the fault region search is with the search tree and the complex current criterion; secondly, a fault description matrix is constructed by using the high association nodes found in the first step. Then elicit the fault judgment matrix with Kirchhoff's law and principle of phase comparison for accurate locating of fault section. This algorithm is adapted to initial structure of the distribution network and the variation of DG, and improve sensitivity of protection by using the complex current. The validity of the new algorithms is verified by the result.of an example.