Decentralized monthly generation scheduling of cascade hydropower plants in multiple time scale markets.

• A decentralized monthly generation scheduling model of cascade hydropower plants is presented. • The water release of the upstream plant is regarded as the coupling variable to achieve decentralization. • The flow-based bilateral contract is designed to increase the revenues of the upstream and downstream hydro plants. • The results of the presented scheduling model, the centralized joint scheduling model and the independent scheduling model are analyzed. Centralized optimization is widely used in generation scheduling of cascade hydropower plants to make full use of reservoir capacity. However, it is very common that the upstream and downstream plants of cascade hydropower system belong to different operators. Therefore, the problems of information privacy and profit distribution are inevitable, which prevents the application of centralized optimization. In order to solve these problems, a decentralized monthly generation scheduling model of cascade hydropower plants in multiple time scale markets is presented in this paper. First, the decoupling method of cascade hydropower plants is introduced. Then a flow-based bilateral contract is designed. The upstream and downstream plants can sign contract to increase their revenues, thereby increasing total revenues of cascade hydropower system. Finally, the hydropower scheduling problem is modelled based on limited information exchange to protect information privacy. The problem is solved by alternating direction method of multipliers (ADMM). The feasibility and effectiveness of the presented model and methods are verified by case studies. [ABSTRACT FROM AUTHOR]