Evaluation of Characteristics and Turn-off dV/dt Controllability of 1.2 kV SiC Si Hybrid Power Switch
Authors & Affiliations
Alireza Sheikhan and Ekkanath Madathil Sankara Narayanan
Department of Electronic and Electrical Engineering
The University of Sheffield
Maintaining high efficiency and low power loss during different load conditions are key requirements for power electronic applications including electrical motor drives. Silicon carbide (SiC) MOSFETs offer fast switching with low losses. However, the cost of SiC MOSFETs is significantly higher compared to silicon (Si) trench IGBTs and will remain so for a considerable future. Also, at high currents, the on-state resistance of SiC MOSFETs becomes higher compared to the slope resistance of Si trench IGBTs. Furthermore, the sharp switching edges of SiC MOSFETs and their high dV/dt can cause degradation of motor winding or failure, detrimental bearing current and electromagnetic interference (EMI). This paper reports the device characteristics, working principle, and dV/dt controllability during turn-off of a 1200V hybrid power switch (HPS) based on parallel configuration of Si IGBT and SiC MOSFET technologies. The results, which are based on the latest IGBT and SiC technologies, show a significant reduction in switching as well as conduction losses and show that such a combination can combine the advantages of both of these technologies while being cost effective. It is demonstrated that the hybrid power switch can achieve switching losses as low as a SiC MOSFET with intelligent control of the device.
Silicon Carbide, MOSFET, IGBT, Hybrid Power Switch, Power Density
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