Coordinated On-line Junction Temperature Estimation and Prognostic of SiC Power Modules

The long-term reliability of power modules is a key factor for most of power electronics applications. Previous work was dedicated to the online monitoring of junction temperature of SiC power MOSFETs via on-state resistance measurement. Among several advantages, temperature monitoring avoids the components failure due to instantaneous thermal overstress. Moreover, as the on resistance tends to grow with the age of the component, temperature monitoring inherently behaves as a precursor of failure, because temperature will be overestimated progressively throughout the lifetime of the component. In this paper the systematic detection of aging of the power semiconductors is proposed, still using the direct measurement of the on-state resistance. A new joint methodology is proposed, based on the initial commissioning of the module both for temperature monitoring and aging evaluation. The identification and monitoring technique is tested on a SiC MOSFET power module.