Design, Modeling and Fabrication of a Symmetric Multilevel Inverter with Optimized Damping Resistor for the Solar Powered Renewable Energy Applications

In this paper, a single-phase, 5-level symmetric, multilevel inverter is designed for solar powered renewable energy applications. This inverter topology is designed with only 5-IGBT switches which is comparatively lower switch counts to the other same level inverters. This study conducts a comprehensive examination of the multilevel carrier-based continuous pulse train with ideal modulation, employing the phase-shift position (POP) technique to ensure precise device switching. Moreover, the single-phase solar powered 5-level symmetric Multilevel Inverter (MLI) is designed, modelled and implemented with the appropriate filters where the damping resistor (rd) is optimized, and practically the FFT measured THD level is 6.33%. The LC and LCL filters are designed using the transfer function and checked the stability from the BODE diagram. In addition, the control algorithm for operating the switches of the designed and simulated inverter is implemented using the C programming language. This allows for embedding of the control section code directly into a Hardware-in-the-open loop (HIL) system.