配电网络电容器优化投切的制约进化策略

Restricted Evolutionary Strategy for Optimal Capacitor Switching in Distribution Systems

针对传统进化规划方法寻优效率低的问题,提出了配电网络电容器优化投切的制约进化策略。利用配电网络物理规则求得投切点无功补偿容量调节范围,用于约束解的产生和进化,缩小寻优空间。通过在解空间中心点附近合理配置初始点,避免初始解不可行。采用小种群多代进化方式,避免求解过程产生大量不可行解。最后选择适合电容器优化投切问题的随机动态步进方式,在寻优的不同阶段,采用不同的步长,使优化效果和效率得到明显改善。使用制约进化策略对不同的配电系统进行分析,结果表明:制约进化策略在保证优化精度的同时,具有更高的优化效率,可以适应在线应用。

To reduce the computing time and improve the efficiency of traditional evolutionary programming, this paper proposes a restricted evolutionary strategy for the optimal capacitor switching in distribution systems. The reactive power compensation ranges are obtained by the physical constraints of the distribution network, and thus the initialization and evolution are restricted to a reduced optimization space. The algorithm＇ s starting points proposed are arranged around the center of the optimization space to prevent infeasihility of the initial solutions. The smaller population and more generations strategy are used to reduce large numbers of infeasible solutions during the optimizing process. Based on the randomly dynamic-step evolutionary method, which takes different steps during different stages of the optimization, the effectiveness and efficiency of optimization are greatly improved. The strategy proposed is tested by different distribution systems, its high efficiency demonstrating its promising online application.