Considerations on the Development of High-Power Density Inverters for Highly Integrated Motor Drives

In transportation electrification, power modules are considered the best choice for power switches to build a high-power inverter. Recently, several studies have presented prototypes that use parallel discrete MOSFETs and show similar overall output capabilities. This paper aims to compare the maximum output power and losses of inverters with different types (surface-mounted, through-hole-mounted and power modules) of commercially available switching devices, and, therefore, discuss the theoretical boundaries of each technology. The numerical analysis relies on detailed power loss and thermal models, with adjustments made for gate current and realistic parameters of the cooling system. The analysis includes two case studies with different targets, including minimum dimensional characteristics and maximum output power. The results demonstrate that discrete MOSFETs can provide improved capabilities in contrast to power modules under certain conditions.