Firefly algorithm for solving non-convex economic load dispatch problem

The main goal of Economic Load Dispatch (ELD) problem is to find an optimal operating condition for the committed generating units in order to minimize the total operating cost while meet the system demand and constraints. The practical ELD problem consists non-convex cost function that challenges the traditional algorithm to obtain the global optimum solution. The input-output characteristics of modern generator are non-linear due to the valve-point effect. This paper presents a new approach for determining the optimal solution for ELD problem based on Firefly Algorithm (FA). To demonstrate the efficiency of the proposed method, three standard test systems are considered based on different sizes of the system. Test system 1 consists of 6 unit generators with non-convex cost function considering the transmission losses while test system 2 and 3 consist of 13 and 40 unit generators respectively without transmission losses. The results of the proposed method have been compared with other methods in terms of optimal cost, convergence characteristics and robustness. It found that the FA can provide better solution compared to MPSO, NPSO and GA-PS-SQP.