SiC JFET Cascode Loss Dependency on the MOSFET Output Capacitance and Performance Comparison with Trench IGBTs

In power electronics there is a general trend to increase converters efficiencies and power densities; for this reason new power semiconductors based on materials such as Silicon Carbide (SiC) and Gallium Nitride (GaN) are becoming more popular. This is especially valid for renewable energies applications where the generated energy has a higher cost than with conventional energy sources. This paper proposes an experimental analysis of the switching performance of a high voltage SiC JFET connected in cascade connection with a low voltage MOSFET. The analysis focuses on the influence of the
MOSFET output capacitance on the switching performance of the SiC Cascode connection in terms of switching energy loss, dV/dt and dI/dt stresses. The Cascode connection switching performances are compared with the switching performance latest Trench IGBTs. The analysis is based on a set of several laboratory measurements and data post-processing in order to properly characterize the devices and quantify whether the SiC JFET Cascode connection can provide good performances with a simple MOSFET gate driver.