Novel configuration for multilevel DC-link three-phase five-level inverter

A new multilevel DC-link three-phase five-level voltage source inverter topology is introduced here. A multilevel DC-link formed from single DC voltage supply and two cascaded half-bridge (CHB) power cells is connected to 12-switch three-phase bridge in such a way that the proposed inverter produces five levels in the output voltage waveform. Compared to comparable inverters, such as symmetrical CHB and hybrid multilevel inverters, the proposed topology maximises the number of voltage levels and reduces the number of utilised DC voltage supplies, switches, gate driver circuits and installation area. A modified fundamental frequency modulation technique based on determination of switching states of inverter is developed, to generate the appropriate switching gate signals. Furthermore, to validate the proposed topology, a low power prototype inverter has been built. The obtained simulation and experimental results ensure the feasibility of the suggested topology and also the compatibility of the used modulation technique.