Doctoral Defense - Matthew Meier

About the Event

The Department of Electrical and Computer Engineering  

Michigan State University  

Ph.D. Dissertation Defense 

Thursday, April 24, 2025, at 10:00 am 

Engineering Building Room 1234 and Zoom 

Contact Department or Advisor for Zoom Information

ABSTRACT

IMPROVED COOLING OF HIGH-SPEED AXIAL FLUX PERMANENT MAGNET MACHINES USING SOFT MAGNETIC COMPOSITES

BY: MATTHEW MEIER

ADVISOR: Dr. ELIAS STRANGAS

High-speed machines are desirable due to their light weight and small size. However, high-speed machines present several challenges. First, stresses increase with rotor speed. Second, losses increase with rotor speed. Finally, the reduced size provides less surface area for cooling. 

Much work has been done to solve these three problems, but the combination of increased losses and reduced surface area remains a limitation to further advancement. While direct cooling provides better cooling than indirect liquid cooling, the coolant in a direct cooling system for a high-speed machine is impractical to exclude from the air gap, and fluid in the air gap of a high-speed machine results in added drag, which increases with speed. 

This paper presents a novel cooling system for high-speed, axial-flux machines that is specifically enabled by the use of SMC materials in the stator core.  A machine is designed in FEA and compared to an indirect cooling system with an attached cooling plate.  The design was built as a prototype and tested experimentally, and the data was used to adjust the FEA thermal parameters.  The FEA model was then used to compare the machine utilizing the novel cooling system to a machine utilizing laminated steel and an attached cooling plate. 

The results of the comparison demonstrate the novel cooling system provides better cooling compared to the traditional design.  In addition, the SMC design was smaller with the same torque (1.65Nm/L vs. 1.57Nm/L), despite the increased loss, and the SMC design rejected roughly 20% more heat per air gap surface area than the laminated steel design. 

Persons with disabilities have the right to request and receive reasonable accommodation. Please call the Department of Electrical and Computer Engineering at 355-5066 at least one day prior to the seminar; requests received after this date will be met when possible.