A Buck Converter with Cost-Effective GaN/Si Hybrid Switches and CRM Operation for High-Efficiency and High-Power-Density Applications

A buck converter with hybrid switches and critical current mode (CRM) operation is proposed in this paper for high efficiency and high power density applications, in which GaN device is used for main switch and Si device is used for auxiliary switch. Comparison studies of the buck converter with hybrid switches, with only Si devices, and with only GaN devices are conducted under the CRM operation to evaluate the performance in terms of power losses and costs. The comparison results demonstrate that the buck converter with hybrid switches can not only achieve the higher efficiency in comparison with the buck converter with only Si devices but also reduce the cost in comparison with the buck converter with only GaN devices, which make it more suitable for the industrial applications. Furthermore, the simulation results present the detailed operation performances of the proposed converter with CRM operation.