Analysis of a short-stroke, single-phase, quasi-Halbach magnetised tubular permanent magnet motor for linear compressor applications

The analysis of a novel single-phase, short-stroke, reciprocating tubular motor with a quasi-Halbach magnetised moving-magnet armature is described. The motor was developed for applications such as linear compressors. The magnetic field distribution, the back-emf and the thrust force of the motor are established analytically in the cylindrical co-ordinate system, and predictions are compared with results derived from finite-element (FE) analysis. It is shown that the difference between the analytical and FE predicted average emf (thrust force) over the operating stroke of 0.01 m is <5%. The analysis and the emf and thrust force predictions are validated by measurements.