A method for optimal floodgate operation in cascade reservoirs

It is difficult to find an algorithm to distribute specific reservoir releases to the floodgates of a hydropower plant in the flood season. In this study, based on a classification of floodgate combinations and the outflow from a hydropower plant, a floodgate table has been established. In order to provide a reasonable scheme for the distribution of releases to the floodgates, this paper summarises the principle of the distribution. A multi-step progressive optimality algorithm (MSPOA) is adopted for optimal floodgate operation in cascade reservoirs and applied to calculate the outflow from each reservoir of cascade reservoirs. Subsequently, according to the summarised principle, the method of bisection is used to search floodgate combinations from the floodgate table for the distribution of releases to the floodgates. To verify its feasibility, the proposed method is applied to optimal floodgate operation in a cascade reservoir system that has four hydropower plants on the Yalong River. A comparison of the application results of the progressive optimality algorithm and MSPOA methods shows that the proposed method can provide reasonable results for flood control and can distribute specific reservoir releases to the floodgates for each reservoir in the cascade reservoir system accurately.