Multispectral Electroluminescence Sensing of SiC MOSFETs for Junction Temperature and Current Extraction

Abstract:
The growing demand for reliability in power electronic systems leads to an increasing need for real-time condition monitoring. In this context, previous research demonstrated how the electroluminescence (EL) of SiC MOSFETs can be used for galvanically-isolated and high-bandwidth temperature and current sensing. However, existing EL-based sensing concepts exhibit poor sensitivity and accuracy when measuring at low currents and low temperatures. Thus, this work identifies key characteristics of the EL spectrum and proposes an improved EL-based sensing technique that measures multiple spectral sensitivities of the EL with optical sensors. The sensing approach is validated by measurements on a SiC MOSFET.