Online measurement of differential drain to source voltage for SiC MOSFETS power module

The on-state resistance R DS ON is a key aging indicator of silicon carbide MOSFETs power module. It can provide information on both chip and packaging degradation allowing more reliable power electronic converter. This on-state resistance can be determined using both the on-state current and voltage of the power semiconductor. This paper focuses on an on-state voltage measurement circuit for SiC MOSFET power module. In the literature, power module bondwires resistance cannot be measured due to high switching voltage oscillations. An on-state voltage measurement circuit that can withstand such oscillations is proposed. The proposed circuit is characterized using the ISO 5725 standard over a wide temperature range. Finally, the circuit is successfully tested on a double pulse bench for various module base plate temperatures and compared to data obtained with a static curve tracer Keysight B1505. • Reliability of Power mosfet Sic is evaluated. • In this work the degradation of the power SiC mosfet is measured online. • The developed solution can clamp up to 200 Vpp voltage oscillation. • Bounding degradation as well as power component ageing is evaluated. • Precision of the measurement stage is 5 mV. • Performance of the proposed system is analysed thanks to 2000 measurements.