集中决策式广域后备保护的分区模型与优化算法

Partition Model and Optimization Algorithm for Wide-Area Backup Protection Based on Centralized Decision-Making Mode

广域后备保护具有整定配合简洁、不受电网潮流转移影响等优点,可有效防止由传统保护隐性故障引发的电网连锁跳闸事故。但如何在实际大规模电网中划分合理的保护区域是其面临的难题。本文针对集中决策式广域后备保护提出了相应的分区评价指标。以电网的分区最长通信距离评价广域通信的实时性,并结合分区经济性和均衡性指标构建了分区目标函数。同时,提出了一种基于二层搜索分区的优化分区算法。该算法通过优化分区搜索节点策略缩短了进化种群中的染色体长度,在自适应优化分区数目的同时,大幅减小了分区算法的搜索空间。基于IEEE 39和118节点系统的仿真表明,所述分区算法在对不同规模电网进行分区时均具有较高的运算效率,并能较好地满足分区评价指标的要求。

Wide-area backup protection has simple setting principle and operates properly under heavy load transfer. However, it is difficult to partition a large-scale power grid into reasonable protected subsystems. This paper presents partitioning evaluation indexes for the wide-area backup protection based on centralized decision-making mode. The longest communication distance of subsystems is applied to evaluate the performance of wide-area communication. Thereafter, the indexes including communication latency, economy and uniformity are integrated to establish partition objective function. Meanwhile, a partitioning optimization algorithm based on two-layer search is proposed. The length of chromosomes in evolutionary population is shortened through an optimization scheme for subsystem search node, and then the number of subsystems can be optimized adaptively and the search space of algorithm is reduced drastically. Simulation tests based on IEEE 39-bus and 118-bus system demonstrate that the proposed algorithm could efficiently partition power grids with different scales and satisfy the requirements of partitioning evaluation index.