Root finding techniques for economic dispatch problems

This paper describes the application of secant method for solving economic dispatch (ED) problem with generator constraints and transmission losses. The proposed algorithm involves the selection of minimum and maximum incremental fuel costs (lambda values) and then the evaluation of optimal lambda is done by root finding techniques at required power demand. The proposed algorithm has been tested on a power system having 6, 15,26 and 40 generating units. The extensive studies have been made on the proposed method to solve the ED problem by taking 120 and 200 units with generator constraints. Simulation results of the proposed approach were compared in terms of solution quality, convergence characteristics and computation efficiency with conventional methods such as lambda iterative method, heuristic methods such as genetic algorithm and meta-heuristic methods such as particle swarm optimization. From the different examples, it is observed that the proposed method provides qualitative solution with less computational time compare to various methods available in the literature survey.