Main Article Content
Electric ship propulsion system has been drawing attention as a solution for savings in energy and maintenance costs. The system is mainly composed of motor, converter and gearbox and required for high torque at low speed. In this situation, transverse flux motors (TFMs) have been proposed to fulfill the low-speed high-torque characteristic due to suitable for short pole pitch and large number of poles to increase torque output. In this trend, we have proposed C-core type motors taking advantage of TFMs’ structure. In this manuscript, a simple design method based on the magnetic-circuit theory and simple modeling of the motor is proposed to search a design parameter for maximizing torque as a pre-process of numerical study. The method takes into consideration the effects of magnetic leakage flux, magnetic saturation and pole-core combination in accordance with the systematic theory. The simple modeling is conducted based on a dense armature structure in previous axial flux motors (AFMs) applied to the new motor design. The validity of the method is verified by 3-D finite element analysis (FEA) and relative error is at most 20%. The minimalist design is shown to be advantageous for effective use in 3-D FEA. As a detailed design by the FEA, high torque density and low cogging to output ratio can be achieved simultaneously in the proposed machine.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).
International Maritime Organization (IMO), Emissions from fuel used for international aviation and maritime transport, Subsidiary Body for Scientific and Technical Advice, SBSTA 35, 2011.
H. Weh, H. Hoffman, and J. Landrath, New Permanent Magnet Excited Synchronous Machine with High Efficiency at Low Speeds, Proc. Elect. Mach., ICEM, 1988.
T. Nakamura, T. Koseki, and Y. Aoyama, A low-speed high-torque permanent magnet synchronous motor – Reducing cogging torque and eddy current loss –, Journal of JSAEM, Vol. 20, No. 2, pp. 410−415, 2012.
T.J. Woolmer, and M.D. McCulloch, Analysis of the Yokeless and Segmented Armature Machine, IEEE Elect. Mach. Drives Conf., IEMDC, pp. 704−708, 2007.
H. Tokoi, S. Kawamata, and Y. Enomoto, Study of High-Efficiency Motor Using Soft Magnetic Cores, IEEJ Trans. Indus. Appli., Vol. 132, No. 5, pp. 574−580, 2011 (in Japanese).
J.F. Gieras, R.J. Wang, and M.J. Kamper, Axial Flux Permanent Magnet Brushless Machine 2nd Edition, Springer, 2008.
Kano, T. Kosaka, and N. Matsui, Study on Optimum Design of Multi-pole Interior Permanent Magnet Motor with Concentrated Windings – Motor Volume Minimization of IPM Motor for Low-Speed, High- Torque Applications –, IEEJ Trans. Indus. Appli., Vol. 127, No. 4, pp. 349−359, 2007 (in Japanese).
M. Markkovic, M. Jufer, and Y. Perriard, Reducing the Cogging Torque in Brushless DC Motors by Using Conformal Mappings, IEEE Trans. Manetics, Vol. 40, No. 2, pp. 451−455, 2004.
D. Zarko, D. Ban, and T.A. Lipo, Analytical Solution for Electromagnetic Torque in Surface Permanent- Magnet Motors Using Conformal Mapping, IEEE Trans. Magnetics, Vol. 45, No. 7, pp. 2943−2954, 2009.
T. Nakamura, J.S. Shin, and T. Koseki, Cogging force reduced by pole-slot combination in a transverse-flux type Permanent Magnet Linear Synchronous Motor, IEE Tech. Meet. Linear Drive, LD-11-030, pp. 41−46, 2011 (in Japanese).
M.R. Harris, G.H. Pajooman, and S.M. Abu Sharkh, The problem of power factor in VRPM (transverse-flux) machines, IEEE Elect. Mach. Drives Conf., IEMDC, pp. 386−390, 1997.
S.M. Husband, and C.G. Hodge, The Rolls-Royce transverse flux motor development, IEEE Elect. Mach. Drives Conf., IEMDC, Vol. 3, pp. 1435−1440, 2003.