Optimization Control Method of Reservoir Level for Cascaded Hydropower Plants Considering Uncertain Electricity Prices

This paper considers the impact of electricity price uncertainty on the operation of hydroelectric power plants. The aim is to optimize reservoir levels for improving power generation benefits of hydropower plants in the electricity market. An improved k-means algorithm is employed to cluster electricity price factors to determine different price scenarios. The Cartesian product method is then used to combine electricity price scenarios with runoff scenarios so that a multi-objective function with the respective consideration of cascaded hydropower generation, spillage control, and energy storage is developed. This model is solved by the NSGA-II algorithm to determine the optimal pre-flood reservoir level range under different water level combinations. The proposed method has been implemented on the operations of cascaded hydropower plants in Southwest China. The results demonstrate that the method can effectively enhance the whole profitability of hydropower plants, and simultaneously ensure orderly drop of water level of cascaded reservoirs.