Device optimization and modeling for resonant power conversion

Resonant conversion offers dramatic reduction in switching stress, enabling an increase in switching frequency until the device once again becomes the limiting factor. However, estimates on the performance of the device in resonant converters do not adequately account for device-circuit interactions that strongly influence the switching losses. Additionally, lack of satisfactory and reliable circuit models for soft-switching performance of power devices hinders the design of optimum soft-switching converters. For these reasons, it is vital to understand device performance in soft-switching applications using physical analysis and optimize it for highest switching frequency. This paper presents a study of the performance of IGBT in a resonant DC link inverter and series resonant inverter, and compares their performance against the voltage source inverter. Due to the contribution of switching losses, it is necessary to develop circuit models that can reliably predict device transient performance.