A Study of Vertical Type Rigid Rotor Supported in Magnetic Bearings using Virtually Zero Power Control

자기베어링으로 지지되는 수직형 강성 로터의 가상적 영 전류 제어 방식에 관한 연구

  • 이준호 (Virginia 주립대학 기계공학과 ROMAC) ;
  • 이기서 (광운대학교 제어계측공학과)
  • Published : 2003.07.01

Abstract

In this paper we deal with the virtually zero power control for the rigid rotor with radial suspension by the permanent magnetic bearing and axial suspension by electromagnetic bearing. The purpose of the virtually zero power control is to reduce the power consumption of the electromagnetic bearings. The axial active force is expressed by the normal second order equation which has only one degree-of-freedom. The virtually zero power control structure has two schemes. One is the coil control current integrator which is used to make the convergence of the control current to a range which is very close to zero. By using the current integrator the DC component which is included in the control current is eliminated, thus the control current converges to a range which is close to zero. The other is normal PD control loop which is used to make the rotor reach to stable equilibrium point and to maintain air gap so that the axial force produced by radial permanent magnet always balances the total weight of the rotor and its load. First we show a simple mathematical plant model and the virtually zero power (VZP) control blocks. Second, we investigate the theoretical feasibility and the stability of the proposed virtually zero Power control levitation system with PD feedback loop by using linear control theory Finally we show the effectiveness of the proposed control method to reduce the power consumption by simulations.

Keywords

References

  1. lyman, J., 'Magnetic Suspension Apparatus', U.S. Patent No. 3,473,852, Octorber 21, 1969
  2. Takechi Misuno, Yuichiro Takemori, 'A Unified Transfer Function Approach to Control Design for Virtually Zero Power Magnetic Suspension', 7th ISMB, August 23-25, 2000
  3. Mimpei Morishita, et al, 'A new Maglev System for Magnetically Leviated Carrier System', IEEE Trans. on Vehicular Technology, Vol. 28, No.4, pp. 230-236, 1989 https://doi.org/10.1109/25.45486
  4. Yeon-Kuang Tzeng, et al, 'Analysis and design of a Near-Zero Power Levitated Maglev System', Journal of the Chines Institute of Electrical Engineering, Vol. 4, No.2, pp. 105-117, 1997
  5. Jean- Paul Yonnet, 'Permanent Magnet Bearings and Couplings', IEEE Trans. on Magnetics, Vol. MAG-17, No.1, pp. 1169-1173, 1981 https://doi.org/10.1109/TMAG.1981.1061166
  6. J. Delamare, J.P. Yonnetm E. Rulliere, 'A Compact Magnetic Suspension with Only One Axis Control', IEEE Trans. on Magnetics, vol. 20, No.6, pp. 4746-4748, 1994 https://doi.org/10.1109/20.334209
  7. M. Marinescu, N. Marinescu, 'A New Improved Method for Computation of Radial Stiffness of Permanent Magnet Bearings', IEEE Trans. on Magnetics, 1994 https://doi.org/10.1109/20.312691
  8. John D. Jackson. 'Classical Electrodynamics', Wiley, 1998
  9. Jun-Ho Lee, et al, 'Displacement-Sensorless Control of Magnetic Bearing System Using Current and Magnetic Flux Feedback (in Korean)', The Transactions of the Korean Institute of Electrical Engineere D, Vol. 49D, No.7, pp 339-345, July, 2000