A "plug and measure" device for junction temperature monitoring in real converter environment

The dimensioning of power electronic products relies on simulation models, which are based on complex measurements for loss and thermal behaviour. A verification of the calculated allowable output power by measuring the junction temperature Tj in operation is often difficult or impossible and requires specially prepared DUTs. In contrast, the presented device allows Tj determination inside the operating final product. It is inserted between the gate driver and the power semiconductor assembly and measures the temperature sensitive internal gate resistor during either the DUT's off or on-state. It can be used for IGBTs and (SiC) MOSFETs ranging from TO packages to high current modules with minimal impact.