Abstract
The dynamic economic emission dispatch (DEED) problem taking into consideration valve-point effects is a complicated non-linear constrained multi-objective optimization problem with non-smooth and non-convex characteristics. DEED determines the optimal generation schedule of committed generating units by minimizing both fuel cost and emission simultaneously under a set of constraints. This paper presents two hybrid optimization methods to solve the DEED problem. The first method combines differential evolution (DE) and sequential quadratic programming (SQP). The second one is hybrid particle swarm optimization (PSO) and SQP. DE or PSO is used as a global optimizer and SQP is used as fine tuning to determine the final optimal solution. Two test systems consisting of five and ten generating units with non-smooth fuel cost functions have been used to illustrate the effectiveness of the proposed methods compared with other methods. The second purpose of this paper is to extend the DEED problem in such a way that its optimal solution can be periodically implemented. (C) 2013 Elsevier B.V. All rights reserved.