带调节池的两级串联水电站负荷调节工况过渡过程研究

Research on Transient Process of Two-stage Series Hydropower Station with Regulating Reservoir under Load Regulation Modes

带调节池的多级串联水电站是应对西南水电基地开发地形复杂难题的主要布置方案。如何实现负荷调节工况下串联电站的流量匹配是保证机组安全稳定运行的关键。为此,从水电站过渡过程与控制角度出发,建立了带调节池的两级串联水电站过渡过程仿真模型,分析了负荷变化下机组转速、出力和尾水管进口压力等机组参数以及调节池水位和流量等水力参数的动态变化。结果表明,在串联电站参与电网调节时,调节池对各级电站的调节品质无影响;但若无后续的调节,串联水电站只能维持短时间内的运行。在部分机组甩负荷后负荷重新分配工况中,负荷分配机组尾水管进口压力均存在明显的下降;负荷分配机组调整时间以及负荷分配方案对串联水电站的运行亦无明显影响。上述研究为两级串联水电站的安全运行提供了一定的技术支持。

The multistage hydropower station with regulating reservoir is a main layout scheme to deal with the complex terrain problems in the development of southwest hydropower base.How to realize the flow matching of series hydropower station under load regulation conditions is the key to ensuring the safe and stable operation of units.For this purpose,from the perspective of hydropower station transition process and control,this paper establishes a two-stage series hydropower station transition process simulation model with regulating reservoir,and analyzes the dynamic variation of unit parameters such as unit speed,output and draft tube inlet pressure,as well as hydraulic parameters of regulating reservoir such as water level and flow under load changes.The results show that the regulation reservoir has no effect on the regulation quality of hydropower stations at all levels when the series power stations participate in the power grid regulation.However,if there is no follow-up regulation,the series hydropower station can only maintain the operation for a short time.Under the load redistribution condition after load rejection of some units,the inlet pressure of the draft tube of load distribution units decreases obviously.The adjustment time of load distribution unit and load distribution scheme also have no significant impact on the operation of series hydropower stations.The above research provides some technical support for the safe operation of the two-stage hydropower station.