"Sharpening Skills..... Serving Nation" Reliability Tests and Thermal Modelling for Switching Device

Abstract — Due to the increasing importance of power electronics in control of devices particularly in electrical vehicles the reliability analysis becomes important. The reliability R�(t) of a component is the probability that this component will perform its intended function after a time ‘t’ in a given operating condition. Nowadays component reliability is not very important by considering only the power losses. For predicting reliability of power electronics components temperature and temperature cycle are to be determined.. The goal of this paper was to accurately simulate power loss and thermal behavior of a IGBT based Inverter using vendor data and a validated electrical model of a IGBT based VSI. Successful creation and implementation of these models can reduce the cost of design and production, increase reliability, quantify the accuracy of the estimated thermal impedance of an IGBT based VSI module, predict the maximum switching frequency without violating thermal limits,predict the time to shut down on a Loss of Coolant Casualty (LOCC), and quantify the characteristics of the heat-sink needed to dissipate the heat under worst case conditions. I