A novel magnetically levitated linear actuator, mainly consisting of a Halbach magnetized moving-magnet armature, a cylindrical frame, a rod, and electromagnetic poles, is presented and analyzed for linear compressors applications. The Halbach magnetized armature naturally generates a periodically distributed magnetic field, which is interacted with that induced by the electromagnetic poles. Therefore, an axially reciprocating thrust force is induced that is inherently suitable for high-frequency drive for linear compressors. A lateral magnetic repulsive force, due to the eddy current induced at the cylindrical frame, to exert upon the rod is generated as long as the rod is deviated in the radial direction. Once the position of the rod is laterally deviated from the central position, the rod is automatically brought back by this magnetic repulsive force. The magnetic field distributions, axial thrust force, and lateral magnetic repulsive force are numerically obtained by governing equations analysis under the cylindrical coordinate. The finite element method, by the commercial software ANSOFT Maxwell with Transient Solver (Ansoft Corporation, Pittsburgh, Pennsylvania, USA), is employed to be compared with and validate the solutions obtained by the governing equations analysis. It is shown that the governing equations analysis extremely agrees with the results by the finite element method. At last, the efficacy of the proposed magnetically levitated linear actuator is examined and verified by intensive computer simulations and experiments.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering