Modified BBO-Based PV Integrated Reduced Component Multilevel Inverter for Mitigating THD

With the escalation in power demand of modern world, necessity of renewable energy source integration is increasing simultaneously. Recent trend of research involving the renewable energy source integration seeks intensive attention to the new designs of cascaded H-bridge (CHB) Multilevel Inverter (MLI) topologies. Provision of multiple isolated sources in CHBMLI is advantageous in interfacing the renewable sources over the traditional MLI which needs several switches. Hence, reduced component count CHBMLI topologies are presiding over the conventional MLI in terms of size, cost, efficiency, electro-magnetic interference (EMI), etc. This work proposes a new topology for 5-level MLI with 5 switches with the objective to minimize the amplitude of the lower order harmonics. The proposed MLI consists of an integrated photovoltaic (PV) source as renewable source of energy, a DC supply and 5 semiconductor switches. For achieving lesser total harmonic distortion (THD) in the output voltage without using filter, an optimization scheme, selective harmonic elimination (SHE), has been used. A new metaheuristic technique namely modified biogeography-based optimization (MBBO) is proposed to optimize the firing angles by using the SHE problem. The proposed technique shows better firing angle optimization in comparison to the other popular techniques, i.e., butterfly optimization algorithm (BOA), biogeography-based optimization (BBO), gravitational search algorithm (GSA), and particle swarm optimization (PSO) when applied in the proposed MLI scheme.