A Study On The Model And Its Application For Short-Term Hydropower Scheduling With Two Temporal Scales Coupled

This paper mainly works on the short-term optimal scheduling problems of reservoir systems, which involves various disciplines including water conservancy, electrical engineering, economics, management science, etc. With many factors related to each other and complicate constraints enforced, this problem is typically a nonlinear programming one. Either the traditional mathematical programming methods or the intelligent algorithms have more or less showed their weakness in dealing with these problems, and therefore, more effective and practical procedures are still and always wanted to narrow the gap between the theoretical research and its engineering applications.With application to a hydropower system that consists of 37 hydroplants under direct control of Yunnan Power Grid, this paper proposes a short-term hydropower scheduling model to optimize and also determine the quarter-hourly unit operating zones as well as power generations. The main innovations or features in this paper are summarized as follows:(1)A modeling idea that employs two coupled temporal scales is proposed and used in short-term hydropower optimal scheduling, which balances the power and the water quarter-hourly and hourly, respectively. This tactic meaningfully reduces the constraint number by taking full advantage of the fact that precisions required in power and water balances respectively are different in practice.(2)The generation model used to schedule the quarter-hourly unit operating zones and energy productions is equivalently decomposed into a reservoirs-cascaded operation and a unit commitment problem, which are solved by using linear programming(LP) and dynamic programming(DP), respectively. This reduction of dimensionality alleviates the difficulty in solving the problem.(3)This work makes meaningful efforts in narrowing the gap between a theoretical research and its engineering applications. The efforts show their advantages in adapting to preferences of shift engineers by prioritizing the objective and constraints, as well as taking account the roles of reservoirs in balancing power demands.(4)Committed to improve the applicability of an engineering project, this work has developed a web application with B/S architecture, which integrates the optimization model mentioned in this paper. This application, deployed in Yunnan Electric Power Dispatch and Control Center, has showed its success in helping to schedule the quarter-hourly hydropower generations.