Short-term scheduling of hydrothermal power system with cascaded reservoirs by using modified differential evolution

A modified differential evolution (MDE) algorithm, for solving short-term hydrothermal scheduling problem is presented. Hydrothermal scheduling involves the optimisation of a nonlinear objective function with a set of operational and physical constraints. Differential evolution, an improved version of a genetic algorithm, is a very simple, fast and robust global optimisation technique. The differential evolution algorithm is modified in order to handle the reservoir end volume constraints in the hydrothermal scheduling. The transmission losses are also accounted for through the use of loss coefficients. The study is extended for the combined economic emission dispatch. The performance of the proposed approach is validated by illustration with two test systems. The results of the proposed approach are compared with those of dynamic programming, nonlinear programming, genetic algorithm and evolutionary programming techniques. From the numerical results, it is found that the modified DE based approach is able to provide a better solution at a lesser computational effort.