Cost Comparison Between GaN-based and Si-based 4.5-kW Single-phase Inverters

This paper presents the converter design and cost comparison between Gallium Nitride (GaN)-based and Silicon (Si)-based 4.5-kW single-phase inverters. For fair comparison, both inverters are optimized under the same requirement as a practical Si PV inverter. The cost of the components are based on the component prices at high quantity. The study shows that although the cost of active devices and heatsink is higher for GaN-based inverter, the overall cost can be $ 19 (10%) lower than Si-based counterpart by using switching frequency 6 times higher, which drastically shrinks the passive filters. A GaN-based prototype is built and tested to verify the design.