Silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) has been widely used in numerous industrial applications owning to their characteristics of low on-state resistance, high thermal conductivity, and high operating temperature. To fully utilize the potential of SiC MOSFET, an accurate device model is desired to evaluate the device performance before fabrication. In this article, an accurate subcircuit based model is used to describe the SiC MOSFET dynamic performance. In the model, the non-linearity of device parasitic capacitance is considered by extracting capacitance values under multiple drain-source voltage values from datasheet. All the possible circuit parasitic inductances are extracted by using ANSYS Q3D. To reduce the model complexity, the threshold voltage based model for MOSFET is adopted. Finally, the subcircuit based model is implemented in MATLAB/SIMULINK. The developed model has the advantages of high accuracy, convenient, fast execution time. The model would be a convenient tool to evaluate the device performance and help understanding the experiment phenomena. To validate the accuracy of the developed model, double pulse test (DPT) results of a 1.2 kV SiC MOSFET (ROHM) from both simulation and experiment are compared, the results shown that the developed model is an effective evaluation tool for the SiC MOSFET performance.
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A High-Accuracy, Low-Order Thermal Model of SiC MOSFET Power Modules Extracted from Finite Element Analysis via Model Order Reduction
Silicon carbide (SiC) MOSFET power modules are being used for high power applications because of their superior thermal characteristics and high blocking voltage capabilities over traditional silicon power modules. This paper explores modeling the thermal process of a SiC MOSFET power module through a high-order finite element analysis (FEA) based thermal model and then reducing the order of the FEA thermal model using a Krylov subspace method. The low-order thermal model has a significantly reduced computation cost compared to the FEA model while preserving the accuracy of the model. The proposed method is applied to generate low-order thermal models for a SiC MOSFET, which are validated by computer simulations with respect to the FEA thermal model.
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- Award ID(s):
- 1663562
- PAR ID:
- 10157404
- Date Published:
- Journal Name:
- 2019 IEEE Energy Conversion Congress and Exposition (ECCE)
- Page Range / eLocation ID:
- 4950 to 4954
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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