Impact Factor(JCC): 0.9458- This article can be downloaded from www.bestjournals.in PERFORMANCE EVALUATION OF THREE EVOLUTIONARY ALGORITHMS FOR SELECTIVE HARMONIC ELIMINATION IN VOLTAGE SOURCE MULTILEVEL INVERTER ADEYEMO, I. A, OJO, J. A. & ADEGBOLA, O. A Department of Electronic & Electrical Engineering, Ladoke Akintola University of Technology, PMB, Ogbomoso, Oyo State, Nigeria ABSTRACT In Selective Harmonic Elimination-Pulse Width Modulation (SHE-PWM) technique, optimal switching angles at fundamental switching frequency are computed such that low order harmonics are eliminated, while the fundamental voltage is obtained as desired. In this paper, ant colony optimization (ACO), particle swarm optimization (PSO), and real coded genetic algorithm (RCGA) were implemented and compared for solving selective harmonic elimination (SHE) equations of an 11-level inverter. Using the same population size and the same step size of modulation index, performance evaluations of the three methods show that PSO is the fastest, RCGA are is the most efficient in terms of low order harmonic elimination while ACO is the most efficient in terms of minimization of total harmonic distortion (THD) over a wide range of modulation indices. Computational results are validated with MATLAB simulations. KEYWORDS: Multilevel Inverter, Ant Colony Optimization (ACO), Particle Swarm Optimization (PSO), Real Coded Genetic Algorithm (RCGA) INTRODUCTION Multilevel power conversion is a rapidly growing area of power electronics with good potential for further development. The concept of utilizing multiple small voltage steps to perform power conversion was developed from the idea of step approximation of sinusoid [1]. The unique structure of multilevel converters enables the construction of relatively high power converters with improved harmonic spectrum using relatively low power semiconductor devices. This has resulted into the ability of the converters to meet stringent power quality and high power demands. There are several advantages to multilevel power conversion approach when compared with the traditional two-level power conversion. The smaller voltage steps yield lower switching losses, improved power quality, lower electro-magnetic interference (EMI), lower voltage change rate (dv/dt), and lower torque ripple [2], [3]. Harmonic elimination in multilevel converters has been the focus of intensive research for many decades. To improve converters performance and output power quality, several modulation techniques used in conventional two-level inverter have been modified and deployed in multilevel inverters. These include sinusoidal pulse width modulation (SPWM), selective harmonic elimination (SHE) method, space vector control (SVC), and space vector pulse width modulation (SVPWM) [4]. SHE method at fundamental switching frequency however, arguably gives the best result because of its high spectral performance and considerably reduced switching loss. Selective harmonic elimination (SHE) or programmed pulse width modulation scheme is a switching technique for inverters that provides direct control over the output waveform harmonics. In this method, the switching angles are chosen (programmed) to eliminate selected BEST: International Journal of Management, Information Technology and Engineering (BEST: IJMITE) ISSN(Print):2348-0513; ISSN(Online): 2454-471X; Vol. 3, Issue 10, Oct 2015, 25-42 © BEST Journals