Modeling and vector control of planar magnetic levitator
- SatCon Technology Corp., Cambridge, MA (United States)
- Massachusetts Inst. of Tech., Cambridge, MA (United States)
The authors designed and implemented a magnetically levitated stage with large planar motion capability. This planar magnetic levitator employs four novel permanent-magnet linear motors. Each motor generates vertical force for suspension against gravity, as well as horizontal force for drive. These linear levitation motors can be used as building blocks in the general class of multi-degree-of-freedom motion stages. In this paper, the authors discuss electromechanical modeling and real-time vector control of such a permanent-magnet levitator. They describe the dynamics in a dq frame introduced to decouple the forces acting on the magnetically levitated moving part, namely, the platen. A transformation similar to the Blondel-Park transformation is derived for commutation of the stator phase currents. The authors provide test results on step responses of the magnetically levitated stage. It shows 5-nm rms positioning noise in x and y, which demonstrates the applicability of such stages in the next-generation photolithography in semiconductor manufacturing.
- Sponsoring Organization:
- Sandia National Labs., Albuquerque, NM (United States)
- OSTI ID:
- 316133
- Journal Information:
- IEEE Transactions on Industry Applications, Vol. 34, Issue 6; Other Information: DN: Paper presented at the 1997 Industry Applications Society annual meeting, October 5--9, New Orleans, LA (US); PBD: Nov-Dec 1998
- Country of Publication:
- United States
- Language:
- English
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