跨省互联水电站群长期多目标联合优化调度

Research on Long-Term Multi-Objective Optimal Operation for Trans-Provincial Hydropower Plants

西南特高压直流水电与受端电网梯级水电构成了非常复杂的跨省互联水电系统,面临新的复杂协调优化问题。为此,以溪—浙直流水电输送工程为背景,提出一种跨省互联水电站群多目标联合优化调度方法。该方法建立了发电量最大和枯期典型日峰谷差率最小的多目标优化模型,并引入目标转换策略将原问题分解为多个不同峰谷差率约束的子问题;在求解过程中,根据流域间水文特性和调节性能差异实现电站分组和汛枯期分阶段协调优化,提出基于负荷重构的直流约束处理策略,并与逐步优化、动态规划逐次逼近混合搜索算法相结合,实现模型高效求解。仿真调度实例表明,所提方法可充分利用送受两端水文和发电特性差异,有效满足电网长期电量和短期调峰需求。

Southwest UHVDC hydropowers and the cascade hydropowers in receiving-end power grid make up an extremely complex trans-provincial interconnected hydropower system.This paper was based on Xiluodu-Zhejiang DC hydropower transmission project.A new multi-objective combined optimal operation method for the trans-provincial interconnection hydropower system was proposed.With this method a coordinated optimization model was established for maximum output of generating capacity and minimum daily peak-valley rate during dry season,and the original problem was decomposed into several sub-problems for different peak-valley constraints through target conversion strategy.At the same time,considering the differences of hydrological characteristics and regulation abilities of hydropower stations across the river basins,these power stations were divided into several groups,and calculation order of the power stations was coordinated during the solving process.This paper combined progressive optimization and dynamic programming with successive approximation of hybrid search algorithm.The coordination and optimization framework of the hydropower stations was established so as to realize efficient solution of the model.Example of simulated scheduling of Xiluodu Plant and the connected power grid showed that,the proposed method could make full use of differences of hydrological characteristics and power generations between sending and receiving ends.It can also coordinate power output of the hydropower stations between flood and dry seasons to effectively meet long-term demand of electricity and short-term peak regulation requirements.