Impact of Electroluminescence Spectrum Sampling on SiC MOSFET Junction Temperature and Current Sensing

The electroluminescence (EL) effect in SiC MOSFETs offers a non-invasive method for sensing key operating states, such as junction temperature and current. However, the performance of such sensing systems is influenced by the channel attributes of the spectral sampling unit, which affect accuracy, bandwidth, and interference immunity. Additionally, the optical coupling method directly impacts the spectral preprocessing requirements and the difficulty of module integration. This work investigates the impact of electroluminescence spectral sampling on device state sensing in detail using a 1200V SiC module operating in a Buck topology and a partial least squares (PLS) sensing model as a case.