A new hybrid heuristic algorithm for the nonconvex economic dispatch problem

Economic load dispatch (ELD) is one of the main tools for optimal operation and planning of modern power systems. To solve effectively the ELD problem, most of the conventional calculus methods rely on the assumption that the fuel cost characteristic of a generating unit is a smooth and convex function, resulting in inaccurate dispatch. This paper presents the design and application of a new efficient hybrid heuristic search method to the economic dispatch problem in power systems considering the valve-point effect, making the modelling of the fuel cost functions more practical. The proposed approach combines in the most effective way the properties of two of the most popular evolutionary optimization techniques now in use for power system optimization, the Differential Evolution (DE) and Particle Swarm Optimization (PSO) algorithms. The combined methodology is validated using a test system consisting of 40 generating units, taking into account the valve-point loading effects. The comparative results with those obtained with some of the most recently published approaches confirm the effectiveness of the proposed approach.