Optimal Hourly Scheduling for Wind–Hydropower Systems with Integrated Pumped-Storage Technology

Abstract

It has been a significant challenge to ensure high-efficiency, stable power supplies in complementary wind–hydropower generation systems, and there are increasing concerns about power curtailment and uncertainty control issues. Pumped-storage technology, which stores energy when it is in excess and provides energy in times of shortage, has been found to be a viable solution to enhance system flexibility and energy efficiency. This study investigated a hybrid wind–hydropower generation system with integrated pumped storage for which the hourly optimized scheduling was assessed using a developed mixed-integer nonlinear mathematical model. The hourly uncertainties involved in wind and hydropower were measured using the k-nearest neighbor algorithm and fuzzy theory, respectively, and dynamic programming was employed to assess the reservoir storage capacity changes during constant periods. With the actual application to a wind–hydro generation system in China, nine hourly scheduling scenarios for different seasons and available reservoir capacities were investigated, from which it was found that the hybrid system was highly self-sufficient in the normal season, and that pumped-storage technology was able to improve wind power efficiency in the case region.