Multiphysics Approach to Numerical Modeling of a Permanent-Magnet Tubular Linear Motor

This paper presents a multiphysics modeling through finite-element (FE) coupled electromagnetic and thermal field analysis of a permanent-magnet tubular linear motor (PMTLM). Two-dimensional axial-symmetric FE steady-state and transient solutions are first obtained for the magnetic-flux-density distribution, cogging force, thrust, and losses of the PMTLM prototype. The FE magnetic field results are then used for the 3-D FE thermal simulation to get the PMTLM temperature distribution. This paper proves that the multiphysics numerical field analysis is a viable tool for the design and performance optimization of PMTLMs. The accuracy of the proposed study has been assessed through prior analytical and experimental results. Regarding the design aspects, some peculiarities in the thermal behavior of PMTLMs are emphasized. Generally, thermal models being not ready to develop, experimental and analytical solutions remain a preferred choice.