Optimization of power quality in cascaded multilevel inverter-genetic algorithm approach

Nowadays high quality power is essential for medical, research and industrial applications to produce good quality results and analysis. In this paper, an attempt has been made to improve the quality of power. A single phase seven level cascaded multi level inverter with identical dc supply is designed to reduce the harmonic components of the output voltage. Genetic algorithm optimization technique is applied to multilevel inverter to determine optimum switching angles there by reducing some higher order harmonics while maintaining the required fundamental voltage. This generalized technique can be extended to multi level inverters with any number of levels. The switching angles for each pulse are determined using Genetic Algorithm which is a evolutionary programming technique. The simulation is carried out in MATLAB/Simulink package and the result is compared with the conventional methods like Newton Raphson. The Total Harmonic Distortion is measured accordingly for different modulation indices. A proto type model of microcontroller based seven level inverter has been designed, fabricated and tested. The results are presented and analyzed and hence the hardware results are verified with the simulation results.