Revista Eletrônica de Potência (Brazilian Journal of Power Electronics)

Keywords: Axial Flux Permanent Magnets Machine, EMC characterization, encoderless, low voltage inverter, vector control

Abstract

This paper reports the results achieved through the development of a prototype of electric wheelchair having direct-drive motors being housed within the wheel rims and designed to achieve performance as required for such a particular 24 V battery-operated vehicle application. The main levels of innovation of the realized prototype are described: the design and construction of two twin AFPM wheel-motor drives; the design and modeling of controllers together with the regulators tuning; the design and realization of the power conversion section; the development of a back- EMF-based method in conjunction with Hall-effect sensors to estimate rotor speed and position. Then, EMC characterization of the electric wheelchair is presented.

[1] F. Caricchi, F. Crescimbini, A. Di Napoli, O. Honorati, E. Santini – Compact Wheel Direct Drive for EV’s” – IEEE Industry Applications Magazine, November/December 1996, Vol. 2, No. 6, pp. 25-32. [2] C. C. Chan, “Axial-Field Electrical Machines – Design and Applications,” IEEE Trans. on Energy Conversion, vol. EC-2, n. 2, June 1987, pp. 294-300. [3] R. Nilssen, S.E. Skaar, R. Lund, T. Skjellnes, S. Ovrebo, E. Lovli, “Design of a Permanent Magnet Synchronous Motor Integrated in the Wheel Rim on Wheelchairs”, Proc. of European Conference on Power Electronics and Applications 2005, Sept. 2005, cd-rom. [4] S. Morimoto, M. Sanada and Y. Takeda, “Sinusoidal Current Drive System of Permanent Magnet Synchronous Motor with Low Resolution Position Sensor”, Proc. of 1996 IEEE IAS Annual Meeting, pp 9- 13, Oct. 1996. [5] J. Bu, L. Xu, T. Sebastian and B. Liu, “Near-Zero Speed Performance Enhancement of PM Synchronous Machines Assisted by Low Cost Hall Effect Sensors”, Proc. of IEEE APEC’98, pp 68-74, Feb. 1998. [6] S. Morimoto, M. Sanada and Y. Takeda, “High Performance Current- Sensorless Drive for PMSM and SynRM with only Low Resolution Position Sensor”, IEEE Transactions on Industry Applications, Vol.39, N°3, pp 792-801 May/June 2003. [7] F. Giulii Capponi, G. De Donato, L. Del Ferraro, “Brushless AC Drive Using An Axial Flux Synchronous Motor With Low Resolution Position Sensors”, Proc. of IEEE 35th Annual Power Electronics Specialists Conference, PESC’04, cd-rom. [8] E. Spooner, B.J. Chalmers, “TORUS – a slotless toroidalstator, permanent magnet generator”, IEE Proceedings – part B, 139, November 1992, pp. 497-506. [9] F. Caricchi, F. Crescimbini, O. Honorati, “Low-Cost Compact Permanent Magnet Machine for Adjustable- Speed Pump Application”, IEEE Trans. on Industry Applications, Vol. 34, No. 1, January/February 1998. [10] P. Pillay, R. Krishnan, “Modeling, Simulation, and Analysis of Permanent-Magnet Motor Drives, Part I: The Permanent-Magnet Synchronous Motor Drive” IEEE Trans. on Industry Applications, vol. 25, no. 2, March/April 1989. [11] G. Vitale, A. Di Napoli, F. Crescimbini, A. Lidozzi, L. Solero, “Combination of SVM Techniques for Electric Drives,” SPEEDAM 2004, cd rom. [12] “Wheelchairs – Requirements and test methods for electromagnetic compatibility of electrically powered wheelchairs and motorized scooters”, ISO 7176-21, 1st ed, 2003. [13] “Industrial, scientific and medical (ISM) radio-frequency equipment – Radio disturbance characteristics – Limits and methods of measurement”, CEI EN 55011 (and relative Amendments A1, A2), 2nd ed, 2003.