Theoretical and experimental investigations on a 12 kW Oxford-Type dual-opposed moving-coil linear compressor

Abstract

This paper presents theoretical and experimental investigations on an Oxford-Type dual-opposed moving-coil linear compressor aiming to achieve an electric input power capacity of 12 kW, which is a great challenge in the moving-coil compressor field. A linearized model is established in which systematic analyses about force balance, mechanical resonance and magnetic circuit are conducted. The relations between air gap and magnetic field intensity in the magnetic circuit are focused on to optimize the motor efficiency, and the design of linear motor and mechanical spring are discussed in a more detailed way. The prototype compressor is worked out and tested, and experimental results are compared with theoretical analyses. The developed compressor will be coupled with a coaxial pulse tube cold head, which is expected to provide 600 W of cooling power at 77 K for cooling the high temperature superconducting (HTS) cables.