基于聚类分析的三阶段二级电压控制分区方法

A Three-stage Network Partition Method for Secondary Voltage Control Based on Agglomerative Analysis

合理的电压控制分区是三级或"软"三级电压控制模式应用的基础,好的分区结果应保证每个分区中都含有无功源,且分区内保持连通性。文中提出一种基于网络结构及电气距离的电压控制分区方法:首先根据网络结构将由辐射状支路连接在一起的无功源并入同一个分区;其次对受控点进行分类处理,在保证分区连通性的基础上将受控点并入电气距离最近的无功源所属分区;最后基于WARD距离对初始分区进行聚类分析,最终确定分区方案。分区聚类仅在有支路连接的相邻分区之间进行,保证了分区结果的连通性,并大大减小了分区聚类的计算量。所述分区方法仅与电网结构及参数有关,与电网的潮流分布无关,能够较好地满足二级电压控制的需要。对IEEE 39节点测试系统及实际电力系统的分区划分结果验证了所述方法的合理性及效率,对实际电力系统二级电压控制具有一定的应用价值。

Proper network partition for secondary voltage control is the prerequisite for the application of three levels orsoft＂three levels voltage control.Good partition should satisfy the conditions that each partition contains at least one reactive power source while maintaining connexity itself.This paper proposes a three-stage network partition method for secondary voltage control based on network structure and electrical distance.Firstly,the method proposed merges the reactive power source nodes connected by radial branches into one and the same partition according to the network structure.Secondly,the controlled nodes are classified into two types,and then merged into the partition to which the nearest reactive power source in electrical distance belongs while keeping the connexity of partitions.Finally,an agglomerative analysis is made on the initial partitions according to WARD distance to determine the final network partitions.Allowing for merger to be performed only between the connected partitions guarantees the connexity of the final partition while greatly reducing the scale of agglomerative computation.The method proposed meets the demand of secondary voltage control as the partition results are related only to the network structure while having nothing to do with the operation conditions,such as power flow distributions.The partition results of an IEEE 39-bus system and Yunnan power system have verified the rationality and efficiency of the proposed method,showing that the method is of definite application value to the secondary voltage control of power systems.