计及阀点效应负荷经济分配的SCE-UA算法

SCE-UA algorithm for economic load dispatch of generators with valve-point effects

针对水火电能源丰枯、峰谷补偿特性,研究水火电力系统补偿调节机制,建立了基于SCE-UA算法解决水火电力系统短期联合优化调度模型,该模型以阀点效应下最小发电成本为目标函数,同时考虑了包括功率平衡、水量平衡、库容及发电机组功率限制等约束条件。本文用罚函数约束策略有效处理系统运行约束,实现对水火电联调系统运行区域的精确描述。为了说明SCE-UA算法的一致有效性,我们分别用SCE-UA和粒子群优化(PSO)两种算法对短期水火电优化调度问题进行求解。计算结果表明:粒子群算法(PSO)算法在求解过程中存在"早熟现象",无法寻找到全局最优解;而SCE-UA算法能在很少的迭代次数内收敛到较好的优化结果,同时满足水火电联调系统所有约束条件。因此,SCE-UA算法在求解以发电成本最小为目标函数的短期水火电优化调度问题上是非常有效的。

According to abundance-shortage and peak-valley compensation features of hydrothermal electricity energy, this study develops a simple and efficient optimization model for short-term hydrothermal scheduling with thermal cost function based on SCE-UA algorithm. This model minimizes electricity generation cost and considers the constraints of hydrotherrnal system like valve-point loading effects of thermal generators, load-generation balance, unit generation limits, reservoir flow balance, and reservoir physical limitations, and the hydrothermal system is equipped with a technique that can effectively handle its operation constraints. To show the model＇s efficiency we used two algorithms to calculate the scheduling. PSO algorithm suffers from premature in its iteration, while SCE-UA algorithm can produce an optimal solution in a few iterations satisfying all the system constraints. Comparison of these algorithms shows that SCE-UA is more efficient in minimizing thermal cost for short-term hydrothermal scheduling with continuous search space.