A Novel Multilevel Inverter Structure for Renewable Energy Applications

Wide band gap switches (WBGS) are the next generation of power electronic switches. Higher efficiency, higher operating switching frequencies, increased power density as well as reduced size and weight and consequently lowering overall system costs are some of WBGS advantages over their Si counterparts. Hence, employing these switches in power electronic converters seems crucial. Inverters are one of the most useful converters in power electronics with a wide range of applications. However, these converters have some drawbacks like low switching frequency limited by Si switches and low efficiency due to high sheet resistance of silicon. By taking the advantage of WBGS in inverters, issues regarding Si switches in these converters can be solved. Therefore, in this paper, a novel GaN-based inverter structure for renewable energy applications is proposed. This inverter has two power supplies, four GaN HEMTs, and two Si MOSFETs. The proposed inverter has the ability to produce up to 7 voltage levels by using two DC sources and up to 5 voltage levels by using one DC source and one capacitor. To show the advantages of the proposed inverter structure, it has been simulated using PSIM. Furthermore, different comparisons are done with similar structures to prove the effectiveness of the proposed inverter in terms of the number of components.