In this work, both static and dynamic characterizations from room temperature to 175 °C were conducted for the latest 6.5 kV silicon carbide (SiC) MOSFETs. A custom clamped inductive load (CIL) test setup is developed for the medium voltage (MV) SiC devices to evaluate the switching energy losses and body diode performance. The various grounding paths due to the parasitic capacitances in the CIL setup are analyzed and reduced to mitigate the impact to the test results. In addition, using these latest 6.5 kV SiC MOSFETs, a 25 kW all SiC series-resonant converter (SRC) is proposed to enable a single stage dc-to-dc conversion from 3 kV to 540 V (± 270 V) aiming the applications on future electric aircraft with onboard MVDC distribution. The proposed SRC consists of a 2-level half bridge converter using 6.5 kV discrete SiC MOSFETs on the primary side, a full bridge converter using 900 V SiC MOSFET modules on the secondary side and a high frequency transformer. Compared with a 3-level neutral-point-clamped converter using 3.3 kV discrete SiC MOSFETs, the efficiency and power density of the 2-level converter are increased.
