Online Converter-Level Temperature Estimation for IGBTs Using Proportional Calibration Method

In this letter, we propose a novel online converter-level junction temperature <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</i><sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">j</sub> evaluation method for insulated gate bipolar transistors (IGBTs) based on the common power loop parasitic inductance voltage overshoot of the bus bar. This temperature sensitive electrical parameter is at an appropriate quantity of several volts with relatively high sensitivity. In addition, to address the issue that different converters and different batches of IGBT modules need to be calibrated repeatedly, this letter proposes a proportional calibration method. Double-pulse test reveals the temperature dependence, and online experimental results of the three-phase converter with calibration method provide a basis for industrial application of the proposed junction temperature estimation method.