Modulated particle swarm optimization for economic emission dispatch

The economic emission dispatch (EED) problem of thermal generating units is a highly complex combinatorial multi-constraint, non-convex optimization problem with conflicting objectives. This paper presents a Modulated Particle Swarm Optimization (MPSO) method to solve the EED problem of thermal units. The conventional PSO is modified by modulating velocity of particles for better exploration and exploitation of the search space. The modulation of particles' velocity is controlled by introducing a truncated sinusoidal constriction function in the control equation of PSO. The conflicting objectives of the EED problem are combined in fuzzy framework by suggesting adjusted fuzzy membership functions which is then optimized using proposed PSO. The effectiveness of the proposed PSO is tested on three standard test generating systems considering several operational constraints like valve point effect, and prohibited operating zones (POZs). The application results and their comparison with other existing methods show that the proposed MPSO is promising for EED problem of thermal generating units.