Analytical analysis and dimensioning of a low-leakage linear transverse-flux machine

This paper presents a two-dimensional analytical analysis and dimensioning procedure of a novel low-leakage linear transverse-flux machine (TFM). The two-dimensional analytical models approximate the complex three-dimensional fluxes of the TFM. The analysis is based upon how the different airgap permeances and the nonlinear iron reluctances in the different machine sections vary, as the translator is traversed through the airgap. The reluctance networks for the magnetomotive force (MMF) of the magnets and for the current dependent armature-MMF are solved simultaneously. A 5-kW proof-of-concept machine is dimensioned and its performance predicted using the described procedure. The different performance defining parameters are derived as continuous functions of the translator position. The dependence of the machine power factor and the force capability upon the current loading, which is quite interesting when analysing TFMs, is also investigated.