Analysis of Temperature Correlation on IGBT Modules

A precise, but simple thermal model of the complete setup of IGBT module, thermal interface and heat sink is essential for achieving high power density in an inverter design without compromising reliability. By applying an experimental method that heats up IGBTs as well as diodes inside an IGBT module using a low voltage AC source, such a model can be derived with little effort. Besides determining the thermal limit of a setup, a proper setpoint value for the NTC can be determined to achieve overload protection based on this measurement.