Economic load dispatch using θ-PSO

This paper presents a theta-particle swarm optimization (theta-PSO) based algorithm to solve constrained economic load dispatch (ELD) problems of thermal plants. The proposed methodology easily takes care of practical constraints such as transmission losses, ramp rate limits, and prohibited operating zones, and also deals with non-smoothness of cost function arising due to the use of valve point effects. The main evaluation mechanism of classical particle swarm optimization (CPSO) is modified in the novel theta-PSO by replacing the velocity vector with a phase angle vector. So, the positions are decided by the mapping of phase angles in theta-PSO. The performance of proposed algorithm has been tested on systems possessing 6, 13, 15, and 40 generating units involving varying degree of complexity. Detailed comparisons under equitable conditions are provided with prevalent approaches to measure the efficiency of the proposed algorithm. The findings affirm that the method outperforms the existing techniques in terms of solution quality and computational efficiency and can be a promising alternative approach for solving the ELD problems in practical power system. (C) 2013 Elsevier Ltd. All rights reserved.