Real-time computation of thermal constraints in multichip power electronic devices

In this paper, we present an implementation of a thermal modeling method, based on thermal impedances analysis and applied to a multichip module used as a power converter. Analytical functions of thermal impedances are derived from direct measurements of chips temperature with optical fiber sensors. We describe an original algorithm with a recurrent procedure to compute directly and accurately the convolution integrals with high speed performances. Finally, experimental measurements, in real working conditions, have been performed in order to complete the validation of the real-time estimation of the junction temperatures of the power electronic package.