利用已建大变幅库水位水电梯级建设混合式抽水蓄能的可行性研究

Study on the Feasibility of Hybrid Pumped-storage Construction Using Existing Cascade Hydropower Stations with Large Reservoir Water Level Fluctuation

利用已建水电梯级新建抽水蓄能电站,是快速满足电力发展需求及消纳新能源的重要手段。为解决已建水库水位大变幅对抽水蓄能定速机组的水头变幅不利影响,以贵州省光马混合抽水蓄能电站为例,根据水库电站及抽水蓄能机组的运行特点,提出以改变水库运行水位为突破口,研究采用定速机组的可行性。分析结果表明,光照水电站水库抬高死水位后,北盘江水电梯级多年平均年发电量增加了0.78亿kW·h,保证出力仅减少4.8%,随着电网负荷的增加,电网有足够的尖峰工作位置满足水电容量的正常发挥;梯级保证出力可满足规范要求。采用定速机组,对原水电梯级作用影响甚微,具有可行性,且建设混合抽蓄可增加双倍调峰能力。该研究成果可供其他类似混合式抽水蓄能电站设计借鉴。

It is an important means to rapidly meet the demand of power development and absorb new energy by using existing cascade hydropower stations to build pumped-storage power stations. In order to solve the adverse effect of large fluctuation of water level of existing reservoir on the fixed-speed pumped-storage units, the Guangma Hybrid Pumped-storage Power Station in Guizhou Province is taken as an example, and according to the operation characteristics of reservoir and pumped-storage unit, the feasibility of using fixed-speed unit in the station is studied through changing the operation water level of reservoir as a breakthrough point. The analysis results show that,(a) after the reservoir dead water level of Guangzhao Hydropower Station is raised, the average annual power generation of Beipan River cascade hydropower stations increase by 78 million kW·h and the guaranteed output has only decreased by 4.8%, and with the increase of the grid load, the grid has enough peak working positions to meet the normal operation of its hydropower capacity;and(b) the guaranteed output of cascade stations meets the specification requirements. The use of fixed-speed units has little impact on existing cascade hydropower stations, which is feasible, and the construction of hybrid pumped-storage power station can double the peak regulation capacity. The research results can be used for reference in the design of other similar hybrid pumped-storage power stations.