Switching Angle Estimation using GA Toolbox for Simulation of Cascaded Multilevel Inverter

Higher power levels can be obtained from utilizing lower voltage levels which was the theory proposed over thirty years ago. Conversion of DC to AC having desired output voltage and frequency can be obtained from two types of inverters which are single level and multilevel inverter (MLI). Amongst all MLI topologies, Cascaded H-Bridge type is taken into consideration for this paper. Advantages of MLI include minimum harmonic distortion, reduced EMI and it can be operated on different voltage levels. Here IGBT‟s are taken as switches which are to be controlled by providing proper switching angles that is generated by any optimization techniques. Here genetic algorithm (GA) is taken as the optimization method and switching angles are derived and the sane is compared with conventional Newton-Raphson (NR) method. Simulation of cascaded H-Bridge multilevel inverter of single phase 5-level, 7-level and 11level cascaded multilevel inverter is presented and the output waveforms were observed using MATLAB.