Multi-physics analysis of double-sided tubular linear machine with misalignment faults

Multi air-gap tubular linear machines usually take the form of a double-sided tubular linear machine (DSTLM). Such machines have a higher space utilisation and higher power density than their single air-gap counterparts, but at the same time the structure is more complex. It is traditionally very difficult to mechanically implement a movement between two slotted stators, whilst maintaining an even air gap distribution. Thermally, the inner stator is another complex aspect of a DSTLM. However, very little understanding of these two aspects and how they influence the performances of tubular machines exists today. Therefore in this paper, the aim is to accurately analyse the influence of temperature rise and eccentricity fault on the performances of DSTLM. A two-way electromagnetic-fluid-thermal multi-physics coupling model of the DSTLM is established. The variations of electromagnetic, fluid and thermal characteristics with the eccentricity are systematically analysed. A physical prototype is manufactured and the analysed results are verified by the experiments.