Asymmetrical Cascaded H-Bridge 41 Level Inverter with Single PV system

In this paper, an asymmetrical cascaded H-bridge 41 level inverter powered by a single Photo Voltaic (PV) unit is presented. The PV unit drives an Interleaved Soft Switched Boost converter (ISSBC) that drives a simple three level inverter and this inverter unit drives a multiple secondary winding transformer. The AC output of the four isolated secondary windings of the transformer are rectified and filtered to deliver four isolated DC voltages in the ratio 1: 3: 9:27. The system incorporates Maximum Power Point Tracking (MPPT) at the front end boost DC-DC converter level. Overall reduced THD is achieved by strategically spacing on the time axis, for each AC cycle, the discrete voltage levels of the 41 level inverter. The existing system of symmetrical configuration operate with more number of switches and more THD when compared with asymmetrical configuration operate with only 5 switches and low THD (1.92%). The mathematical formulation, the results of simulation in the MATLAB / SIMULINK environment are provided.