IEEE Transactions on Power Electronics, cilt.38, sa.7, ss.8643-8653, 2023 (SCI-Expanded)
A novel soft-switched three-level T-type inverter (3LT2I) is proposed in this paper. The proposed inverter provides turning-on by zero voltage transition (ZVT) and turning-off by zero voltage switching (ZVS) for main switches without any voltage or current stresses. The switching energies are transferred to the snubber capacitors, so the turning-off process of the main switches is improved by these snubber capacitors. Besides, the auxiliary switches are turned on by zero current switching (ZCS) and turned off by ZVS. Furthermore, all snubber diodes are operated by soft switching (SS), and the proposed SS snubber cell decreases the electromagnetic interference (EMI) noises. The novel snubber cell has a simple structure, ease of application, common-ground switches, and low-cost features. The theoretical analysis of the inverter is clarified, and the operating modes for steady-state analysis are presented in detail. The experimental results rated 1 kW output power and 100 kHz switching frequency are provided to justify the theoretical analysis. The proposed unique snubber cell can be easily implemented in other three-level inverters (3LIs), and the practice is demonstrated in the paper.