Enhanced power quality of MLI using PSO based selective harmonic elimination

Multilevel inverter (MLI) has various advantages such as less EMI issues, voltage stress and switching losses, it is a best choice for industrial application. In tradition inverters, Harmonics can be eliminated by using large size of filters due to the lower order harmonics. This leads to increase the overall size, volume and cost of an inverter. But in MLI, the implementation of selective harmonic elimination (SHE) techniques eliminates lower order harmonics. In this work, the Particle Swarm Optimization algorithm (PSO) is applied to find the optimum switch angles which eliminates the lower order harmonics. PSO based optimization is applied for seven and nine level MLI. The simulation results are much closer with experimental result for seven and nine level inverter which provides better solution in comparison with existing algorithm.