Investigation into Temperature Dependency on Thermal Characterization of IGBT Modules Based on Structure Function

To diagnose health status of the insulated gate bipolar transistor (IGBT) power module, structure function (SF) is extensively adopted to evaluate the thermal resistance, as well as to extract the RC parameters of physical thermal network model (TNM). Nevertheless, conventional structure function estimation of the TNM operates under the assumption that the thermal RC parameters remain constant with respect to temperature. This theoretical condition is not applicable in practice, especially when IGBT modules are exposed to elevated temperatures. The influence of variation of temperature on thermal characterization of t TNM extracted by the SF is experimentally and theoretically examined in this article.