Comparative evaluation of SiC and Si PV inverter systems based on power density and efficiency as indicators of initial cost and operating revenue

In this paper, two three-level three-phase all Si PV inverter topologies are compared to a standard two-level three-phase topology employing SiC-based power transistors. In a comparative evaluation based on multi-objective component modeling, the performance trade-offs between achievable efficiency and power density are systematically analyzed for all systems. On the one hand, this is to investigate the potential of SiC to decrease the system complexity while achieving similar or better performance. The analysis shows that a similar power density and efficiency can be obtained with the SiC two-level system while requiring only one tenth of the chip area when compared to the three-level Si inverters. On the other hand, in a next step, using power density and efficiency as indicators for initial inverter cost and operational revenue, the trade-off analysis will allow to determine the economically optimal system dimensioning.