Simulation and characterization of wide band gap power semiconductor devices

Abstract

Wide bandgap (WBG) semiconductors play a pivotal role in improving the efficiency of power electronics due to their exceptional performance characteristics, such as higher reverse breakdown voltage, higher operating temperature, higher frequency, and compact converter size. However, the superiority of WBG semiconductors over traditional silicon ones in power converters is still debatable. In this project, we investigate the performance of silicon carbide (SiC) which is one of the most representative WBG semiconductors, and compare it with silicon (Si) semiconductor devices using PLECS simulator across various converter types and input voltage ranges from 100V to 800V, focusing on voltage and current, MOSFET junction temperature, and converter efficiency, which are primary characteristics to determine the performance of devices. Results from simulations show SiC MOSFETs have better thermal performance, maintaining lower junction temperatures than Si MOSFETs, especially at higher input voltages. Furthermore, SiC maintains stable high efficiency in high-voltage applications across four various converters. Si remains comparable efficiency at lower voltages and advantageous in the DC-DC Buck converter below 200V and DC-DC Boost converter below 600 V due to its cost and manufacturing advantages. Therefore, the selection between Si and SiC semiconductors relies on specific application needs. SiC is ideal for high-voltage, high-efficiency, and thermally demanding applications, while Si remains relevant for cost-sensitive, lower-voltage scenarios, particularly in DC-DC converter applications.