A Compact Calculation Method for Dynamic Electro-thermal Behavior of IGBTs in PWM Inverters

Abstract

Power modules including IGBT (insulated gate bipolar transistor) are widely used in the applications of motor drivers. The design optimization of the modules associated with the device characteristics, the module structures and the cooling conditions has become a major issue with the increase of the current density and the demand of downsizing the modules. In this paper, we propose a compact calculation method of dynamic electrothermal behavior of IGBT PWM (pulse width modulation) inverter modules. The dynamic electro-thermal calculations are performed using familiar spreadsheet software. In this approach, the mathematical models of the temperature dependencies of the device losses and quasi one-dimensional difference equations of thermal conduction were used for the estimation of the temperature of the module. To narrow down a lot of device and module parameters, the proposed approach will be an effective tool in the initial stage of thermal design of the inverter modules.