Solving non-smooth economic dispatch by a new combination of continuous GRASP algorithm and differential evolution

The power economic dispatch is one of the most important problems in power system operation. Its objective is to minimize the total generation cost of the generating units while satisfying various constraints of the units and system. In past decades, modern metaheuristics have been applied in solving the economic dispatch problem due to their ability to find an almost global optimal solution. Recently, inspired in classical GRASP (Greedy Randomized Adaptive Search Procedure) algorithm, Hirsch et al. (2006) proposed a novel variant of the GRASP for continuous domain, called continuous GRASP (C-GRASP) algorithm. This paper proposes a combination of C-GRASP and differential evolution (DE) algorithm (C-GRASP-DE) in order to improve the global searching capability and prevent the convergence to local minima. The feasibility and performance of proposed C-GRASP and DE is demonstrated by power systems consisting of 13, 40 and 140 generators whose fuel cost function is calculated taking into account the effect of valve-point loading. Simulation results demonstrate the superiority of the proposed C-GRASP in combination with a self-adaptive DE approach (C-GRASP-SaDE) compared to the classical C-GRASP. Furthermore, some obtained optimization results for the three case studies by the proposed C-GRASP-SaDE are competitive with the best results presented in recent literature.