Closed-form Method for Multi-stage Axial Flux Permanent Magnet Machine: Design and Analysis

Abstract

Designing an axial flux permanent magnet machine is complex and computationally intensive. This paper proposes a new closed-form method for concurrent design and analysis of a multi-stage axial flux permanent magnet machine. The method will provide a simpler modeling solution to machine designers. By calculating magnetic and electric properties, the design space of an axial flux permanent magnet is created for initial design. This paper demonstrates the feasibility of the new closed-form method by showing that the results obtained from the proposed method correlate with the finite element analysis results. The design space is also evaluated and analyzed by taking into account various parameters, including copper losses, permanent magnet density, phase voltages, and torque waveform. Finally, a multi-objective analysis is performed to compare two different designs of an axial flux permanent magnet machine. The proposed method also provides a useful guide for the initial design state.

Keywords::

• analytical
• axial flux
• back-EMF
• closed-form
• design
• dual structure
• electric machine
• permanent magnet
• torque
• optimization

BIOGRAPHIES

Ju Hyung Kim received his B.S. degree from Yonsei University, Seoul, Korea, in 2008 and his M.S. degree from the University of Wisconsin–Madison, in 2014, all in electrical engineering. He is currently pursuing his Ph.D. in electrical engineering at the University of Wisconsin–Madison. From 2008 to 2011, he was an electrical engineer with Hyundai Heavy Industries, Ulsan, Korea. He is a student member of the IEEE. His research interests include electrical machine design and machine drives.

Bulent Sarlioglu received his B.S. degree from the Istanbul Technical University, in 1990, his M.S. degree from the University of Missouri-Columbia, in 1992, and his Ph.D. degree from the University of Wisconsin–Madison, in 1999, all in electrical engineering. Since 2011, he has been an assistant professor at the University of Wisconsin–Madison and the associate director of the Wisconsin Electric Machines and Power Electronics Consortium (WEMPEC). From 2000 to 2011, he worked at Honeywell International Inc.’s aerospace division, most recently as a staff systems engineer, Torrance, California. He received the Honeywell's an outstanding engineer award in 2011. He is a senior member of the IEEE. His expertise includes electrical machines, drives, and power electronics, and he is the inventor or co-inventor of 16 US patents as well as many international patents.