A Physical RC Network Model for Electrothermal Analysis of a Multichip SiC Power Module

Li, Jianfeng; Castellazzi, Alberto; Eleffendi, Mohd Amir; Gurpinar, Emre; Johnson, Christopher Mark; Mills, Liam

Abstract

© 2017 IEEE. This paper is concerned with the thermal models which can physically reflect the heat-flow paths in a lightweight three-phase half-bridge two-level SiC power module with six MOSFETs and can be used for coupled electrothermal simulation. The finite-element (FE) model was first evaluated and calibrated to provide the raw data for establishing the physical resistor-capacitor (RC) network model. It was experimentally verified that the cooling condition of the module mounted on a water cooler can be satisfactorily described by assuming the water cooler as a heat exchange boundary in the FE model. The compact RC network consisting of 115 R and C parameters to predict the transient junction temperatures of the six MOSFETS was constructed, where cross-heating effects between the MOSFETs are represented with lateral thermal resistors. A three-step curve fitting method was especially developed to overcome the challenge for extracting the R and C values of the RC network from the selected FE simulation results. The established compact RC network model can physically be correlated with the structure and heat-flow paths in the power module, and was evaluated using the FE simulation results from the power module under realistic switching conditions. It was also integrated into the LTspice model to perform the coupled electrothermal simulation to predict the power losses and junction temperatures of the six MOSFETs under switching frequencies from 5 to 100 kHz which demonstrate the good electrothermal performance of the designed power module.

Citation

Li, J., Castellazzi, A., Eleffendi, M. A., Gurpinar, E., Johnson, C. M., & Mills, L. (2018). A Physical RC Network Model for Electrothermal Analysis of a Multichip SiC Power Module. IEEE Transactions on Power Electronics, 33(3), 2494-2508. https://doi.org/10.1109/TPEL.2017.2697959

• Journal Article Type: Article
• Acceptance Date: Apr 15, 2017
• Online Publication Date: Apr 25, 2017
• Publication Date: 2018-03
• Deposit Date: Apr 26, 2017
• Publicly Available Date: Apr 26, 2017
• Journal: IEEE Transactions on Power Electronics
• Print ISSN: 0885-8993
• Electronic ISSN: 1941-0107
• Publisher: Institute of Electrical and Electronics Engineers
• Peer Reviewed: Peer Reviewed
• Volume: 33
• Issue: 3
• Pages: 2494-2508
• DOI: https://doi.org/10.1109/TPEL.2017.2697959
• Keywords: MOSFETs, SiC power module, Finite element methods, RC network, Curve fitting, Three-phase inverters
• Public URL: https://nottingham-repository.worktribe.com/output/857475
• Publisher URL: http://ieeexplore.ieee.org/document/7911340/
• Additional Information: 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works