JEE_V2_N1_RP5 Millie Pant Radha Thangaraj Ajith Abraham Ved Pal Singh Journal on Electrical Engineering 2230 – 7176 2 1 36 43 Evolutionary algorithms, Particle swarm optimization, PI tuning, Permanent magnet synchronous motor Optimization is one of the most discussed topics in engineering and applied research. Many engineering problems can be formulated as optimization problems. During the last few decades, many general-purpose optimization algorithms have been proposed for finding optimal solutions, some of which are; Evolution strategies, evolutionary programming, Genetic algorithms (GA), Particle Swarm Optimization (PSO) and Differential Evolution (DE).This paper presents a comparative study of three popular, Evolutionary Algorithms (EA); Genetic Algorithms, Particle Swarm Optimization and Differential Evolution for optimal tuning of Proportional Integral (PI) speed controller in Permanent Magnet Synchronous Motor (PMSM) drive. Average gain function and weighted average gain function are also considered to improve the fitness function. Numerical results show the superior performance of DE in comparison to PSO and GA. July - September 2008 Copyright © 2008 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=328