RCD snubber circuit design for 5-level 4-switch DC-AC converter

This paper presents an optimized single phase DC-AC converter with RCD snubber circuit. The proposed converter has an optimized number of levels per number of switches (nL/nS) which is by far the best relationship among the converters proposed in literature. The most important characteristics of the proposed configuration are: (i) reduced number of semiconductor devices, while keeping a high number of levels at the output converter side, (ii) only one DC source without any need to balance capacitor voltages, and (in) reduced semiconductor losses and as a result higher efficiency. The principle of operation, RCD snubber design, modulation technique, and modeling of the proposed converter are presented in this paper. The proposed multilevel DC-AC converter topology is simulated and validated experimentally.