A Novel Constraints Handling Method for Economic Dispatch with Valve-Point Effects

Economic dispatch with valve-point effects is a nonlinear and nonconvex problem in power systems. In addition to the optimization algorithm, the handing method of constraints including equality and inequality is one of the important factors for solving the economic dispatch problem. This paper presents a novel constraints handling method for solving economic dispatch with valve-point effects, consisting of the power repair strategy and the adaptive penalty function. The power repair strategy modifies the generator output power according to the characteristics of the valve-point. The penalty function changes according to the fitness value of the objective function. The method is applied to the economic dispatch problem solved by the standard differential evolution algorithm, and tested in 13-unit, 40-unit, 80-unit, 140-unit systems. The simulation results show that the proposed method can effectively increase the stability of convergence and improve the accuracy of solution for solving economic dispatch problem with valve-point effects.