A Sparsity-Promoting Time Domain Evaluation Method for Thermal Transient Measurement of Power Semiconductors

IEEE Transactions on Power Electronics, vol. 39, pp. 7525–7535

Abstract

This article investigates evaluation methods of thermal transient measurements to obtain the internal thermal structure of semiconductor devices. First, the study uncovers the limitations of a widely accepted standard method that uses frequency-domain deconvolution. An important finding is that the sideband of the time constant spectrum by the standard method has no physical meaning despite it beeing interpreted as a continuous spectrum for a long time. Second, by understanding the limitations of the existing method, the article proposes an alternative method that remodels the frequency-domain deconvolution as a regularized least squares problem in the time domain. With the benchmark of the true values of several thermal networks based on simulation, the proposed sparsity-promoting method demonstrates several advantages, including a better ability to identify adjacent parameters in the time-constant spectrum and the obtained structure function reducing relative error by an order of magnitude. The influence of varying noise levels has also been evaluated. Finally, a proof-of-concept experiment using a commercial power semiconductor device validates its effectiveness.

Authors 5

1. Yi Zhang

   Aalborg University

   Affiliation as printed

   AAU Energy, Aalborg University, Aalborg, Denmark

2. Anton Evgrafov

   Aalborg University

   Affiliation as printed

   Department of Mathematical Sciences, Aalborg University, Aalborg, Denmark

3. Shuai Zhao

   Aalborg University

   Affiliation as printed

   AAU Energy, Aalborg University, Aalborg, Denmark

4. Sven Kalker Aachen Institute for Power Electronics and Electrical Drives (ISEA)

   RWTH Aachen University

   Affiliation as printed

   Institute for Power Electronics and Electrical Drives (ISEA), RWTH Aachen University, Aachen, Germany

5. Rik W. De Doncker Aachen Institute for Power Electronics and Electrical Drives (ISEA)

   RWTH Aachen University

   Affiliation as printed

   Institute for Power Electronics and Electrical Drives (ISEA), RWTH Aachen University, Aachen, Germany