A Study on the Magnetically Suspended Spindle with 16-pole Radial Magnets

16 극의 반경방향 전자석을 갖는 자기부상 주축계 연구

  • 박종권 (한국기계연구원 자동화연구부) ;
  • 노승국 (한국기계연구원 자동화연구부) ;
  • 경진호 (한국기계연구원 신교통기술연구부)
  • Published : 2002.02.01

Abstract

Active magnetic hearings allow much high surface speed than conventional ball bearings and therefore greatly suitable for high speed cutting. This paper describes a design and test of an active magnetic bearing system with 16-pole radial magnets. The spindle is originally designed for a CNC lathe and driven by outer motor with 5.5 kW power and maximum speed 10,000 rpm. Considering static load condition and geometric restrictions, radial magnet is designed 16-pole type for smaller outer diameter of the spindle system. Dynamic system characteristics such as natural frequency, critical speed, stiffness, damping and system stabilities are simulated with a rigid rotor model including direct feedback controller. The designed spindle system is realized with digital PIDD controller to compensate phase lag of PWM amplifier and magnet coils. With levitation and step response experiment the control system characteristics are tested, and the spindle is rotated up to 10,000 rpm stab1y.

Keywords

References

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