Hydro-thermal-wind-photovoltaic coordinated operation considering the comprehensive utilization of reservoirs

Abstract

The increasing integration of new energy into the power system has brought new challenges to the operation of the power systems and increased the operation difficulty of peak shaving plants. In the multi-energy power systems, the hydropower plants not only conduct peak load regulation to reduce thermal power fluctuation, but also balance the new energy power output fluctuation. However, the comprehensive requirements of various water-using departments have severely restricted the regulating capacity of hydropower stations. This paper aims to explore the relationship between the outflow of hydropower plants and coordinated effectiveness by setting different water availability scenarios. For this purpose, a coordinated operation model of power systems with hydro-thermal-wind-photovoltaic power considering the comprehensive utilization of reservoirs is proposed. The model seeks to maximize the clean energy power generation and minimize the remaining load fluctuation by taking advantage of the peak regulation capacity of hydropower plants. In the model, the adaptive simultaneous peak regulation strategy of hydropower plants is used to determine reasonable and executable hydropower generation plan. Qinghai power grids is selected as a case study to verify the effectiveness of the proposed model compared to a model without the same strategy. Moreover, the results under various average daily outflow in winter and summer are analyzed to explore the appropriate ranges of hydropower plants daily outflow in different seasons. The results show that the proposed model can increase the new energy power generation, decrease the thermal power output fluctuation, and improve the operation performance of cascade hydropower plants. The average daily outflow has high impact on the operation of hydropower plants and further influences the operation of other energy sources. Furthermore, the appropriate average daily outflow of hydropower plants in Qinghai power grids in winter and summer are evaluated. This study can provide an approach to make daily operation plan for power systems with large-scale new energy and multiple hydropower plants, as well as provide reference for the coordination between hydraulic and electrical power systems.