Microfabricated High-Speed Axial-Flux Multiwatt Permanent-Magnet Generators-Part I: Modeling

• Published in: Journal of microelectromechanical systems Vol. 15; no. 5; pp. 1330 - 1350
• Main Authors: Das, S., Arnold, D.P., Zana, I., Park, J.-W., Allen, M.G., Lang, J.H.L.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.10.2006; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: AC generators; Applied sciences; Computational modeling; Core loss; Electric potential; Electrical engineering. Electrical power engineering; Exact sciences and technology; Generators; High voltage or high current generators; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Magnetic analysis; Mathematical analysis; Mathematical models; Maxwell's equations; Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; micromachining; Micromechanical devices and systems; permanent-magnet (PM) machines; Physics; Power generation; power microelectromechanical systems (MEMS); Power system modeling; Precision engineering, watch making; Rotors; Stator cores; Stators; Synchronous generators; Synchronous machines; Two dimensional displays; Various equipment and components; Voltage; Electric generator; permanent-magnet (PM) machines; Micromachining; Quasi static theory; AC generators; Modeling; Finite element method; Inductance; Winding; power microelectromechanical systems (MEMS); Permanent magnet; Eddy current; Microelectromechanical device; Hysteresis
• ISSN: 1057-7157; 1941-0158
• DOI: 10.1109/JMEMS.2006.880282

This paper presents the modeling of permanent-magnet (PM) generators for use in microscale power generation systems. The generators are three-phase, axial-flux, synchronous machines, each consisting of a multipole, surface-wound stator and PM rotor. The machines are modeled by analytically solving two-dimensional (2-D) magneto-quasi-static Maxwell's equations as a function of radius. The 2-D field solutions are then integrated over the radial span of the machine to determine circuit parameters such as open-circuit voltage and inductance as well as hysteresis loss in the stator core and eddy current losses in the stator core and windings. The model provides a computationally fast method to determine power and efficiency of an axial-flux PM machine as a function of geometry, speed, and material properties. The open-circuit voltage predictions are also shown to agree well with 3-D finite-element analysis simulation results. 1700