Electrical & Computer Engineering, Department of
First Advisor
Liyan Qu
Second Advisor
Jun Wang
Date of this Version
5-2024
Citation
A thesis presented to the faculty of the Graduate College at the University of Nebraska in partial fulfillment of requirements for the degree of Master of Science
Major: Electrical Engineering
Under the supervision of Professors Liyan Qu and Jun Wang
Lincoln, Nebraska, May 2024
Abstract
Silicon Carbide (SiC) Field-Effect Transistor (FET) modules lead the way in power electronics, being superior in efficiency and robustness for high-frequency applications. The shift towards SiC from traditional silicon (Si)-based devices is driven by its superior thermal conductivity, higher electric field strength, and operational efficiency at elevated temperatures. These features are critical for the development of next-generation, grid-oriented power converters aimed at enhancing the reliability and sustainability of power systems. This research focuses on high-frequency press-pack (HFPP) SiC FET modules, addressing the primary challenge of miniaturizing SiC FET dies without compromising performance, through an innovative press-contact design essential for increased high-frequency efficiency.
The objective of the research is to develop and validate a novel monolithic spring (MS) for HFPP SiC FET modules, aiming to surpass conventional press-pack (PP) limitations. By machining airgap slits from a beryllium–copper block, the proposed MS design seeks to achieve optimal mechanical and electrical performance, targeting a linear spring constant, minimal stray inductance, and enhanced high-frequency body resistance. This approach combines theoretical modeling, finite element analysis (FEA) simulations, and experimental validation to overcome the inefficiencies of existing designs, thereby advancing HFPP SiC module technology and supporting the broader adoption of SiC FET in power systems. Additionally, FEA simulations are employed to contrast the novel MS design with traditional Si-based transistors, highlighting the MS's advanced performance and efficiency in high-frequency applications. The research signifies a vital step towards improving the performance and sustainability of electrical grids worldwide, demonstrating the potential of SiC technology in transforming power conversion systems.
Advisors: Liyan Qu and Jun Wang
Included in
Computer Engineering Commons, Materials Science and Engineering Commons, Other Electrical and Computer Engineering Commons
Comments
Copyright 2024, Bogac Canbaz. Used by permission