Distribution of Semiconductor Device Losses in Photovoltaic Transformerless Grid Connected Inverter Topologies

This paper examines losses distribution of devices in various H-Bridge single-phase grid-connected transformerless inverter systems. Topologies of the transformerless inverter with an ac-bypass circuit and dc-bypass circuit are investigated and verified by simulation results. To achieve maximum power conversion efficiency, the selected power semiconductor (IGBT and Diode) plays an important part in the inverter system design. Therefore, the power losses in the devices are also studied and analyzed in this paper. The power losses consist of power conduction losses and power switching losses. The estimation of the power semiconductor losses is verified by PSIM 9.0 software with the thermal module. This estimation is based on the insulated gate bipolar transistors (IGBTs) and diode manufacturer datasheets, which are included in the thermal module. The parameters given in the thermal module devices datasheet contribute to the level of power semiconductor losses in various photovoltaic H-Bridge transformerless grid-connected inverters. In this paper, the HGTG20N60A4D Fairchild Semiconductor and PS21A79 Powerex IGBT antiparallel diode devices have been simulated and analyzed. In conclusion, using the good thermal module in PSIM 9.1 software, distribution losses in devices can be managed, and the performance of transformerless inverter circuits can be organized.