New modified CHB multilevel inverter topology with elimination of lower and higher order harmonics

The main objective of this study is the improvement of output voltage waveform quality generated by a new modified Cascaded H-bridge (CHB) multilevel inverter using Selective Harmonic Elimination (SHE) method and passive LC filters. A PWM technique with SHE is used to control fundamental harmonic and eliminate harmonics of chosen lower-order in CHB multilevel inverter. A passive LC filter is added to the inverter in order to eliminate the high-order harmonics. The switching angles are drawn by solving a non-linear equations system using Hybrid Genetic Algorithm (HGA). In order to evaluate the performance of the HGA in solving the non-linear equations of the system presented in this study, the proposed optimization algorithm was compared to the well-known particle swarm optimization method. Different cases including 5- and 7-level inverters with different values of modulation indices are reported. The simulation findings are validated through experimental results