一种实用的配电网无功运行两层优化方法研究

针对多时段动态无功优化,将控制设备动作次数转化成设备调节费用并将其计入目标函数,建立以全天网损费用与设备调节费用之和最小为目标函数的优化模型。将Fisher有序聚类算法引入到负荷曲线分段问题中,使分段后的负荷曲线尽可能贴近实际负荷水平。提出一种基于改进遗传算法和准动态规划法的两层优化算法,以获取全天控制设备的动作方案,实现多时段的协调优化。为兼顾算法的寻优速度和搜索精度,可依据电网规模灵活设置各阶段保留的最优路径数,适合于大规模系统的动态无功优化。算例表明了所提方法的实用和有效。

A practical two-phase optimization method of dynamic var optimization in a distribution system

For multi-period dynamic var control optimization, a dynamic optimization model is used, in which the objective function is the minimum summation of network loss coat and regulating cost of controlling devices. A Fisher ordered clustering algorithm is employed to segment a load curve, making the load curve close to the actual load change. A two-phase optimization method is presented to acquire a multi-period coordinated optimization based on a modified genetic algorithm and a quasi-dynamic programming. In order to take into account both solution speed and accuracy, the number of optimal paths to be recorded for all stages can be set flexibly according to the system size, which is suitable for the dynamic var control optimization of a large-scale system. The results show that the proposed method is practical and effective.