Energy-saving generation scheduling strategy of hydropower and thermal power plants considering cascaded hydropower stations

Considering the overall benefit among generating unit output, energy consumption cost and pollution emission of thermal power plant and that between output of cascaded hydropower stations and hydraulic coupling parameters as well as that between hydropower generating units and thermal power generating units, a comprehensive multi-objective energy-saving scheduling model, in which the minimized surplus water quantity of cascaded hydropower stations, the lowest energy consumption cost of thermal power plant and minimized pollution emission are taken as the objectives, is established, and an energy-saving generation scheduling strategy of hydropower and thermal power plants, in which the cascaded hydropower stations are taken into account, is proposed. Using scale conversion method, the built multi-objective scheduling model is turned into single objective function with different weight coefficients, and utilizing the mixed penalty function optimization algorithm the solution of the model is turned into unconstrained optimization problem and this optimization algorithm is modified by Hessian matrix, thus the selection of reduction coefficient is solved. Through the simulation of a hydropower-thermal power system containing four cascaded hydropower stations and three thermal power plants, the feasibility of the modified optimization algorithm is validated by optimization results, besides simulation results also show that using the proposed method an obvious energy-saving effect can be achieved.