Fallout of the Mover Eccentricity on the PM Eddy Current Loss of Quasi-Halbach T-LSMs

The paper is aimed at an investigation of the effectsof the mover eccentricity on the PM eddy current loss oftubular-linear synchronous machines (T-LSMs) equipped withquasi-Halbach magnetized PMs. The study is initiated by ananalytical prediction of the no-load spatial repartition of the fluxdensity taking into account the non-coaxiality of the mover andstator, and its validation by a 3D finite element analysis (FEA).Then a special attention is paid to an analytical formulationof the PM eddy current loss in presence of eccentricity. Thisis achieved considering the case of the radially-magnetizedPMs and the axially-magnetized ones. The developed modelenables the investigation of the eddy current loss versus themover eccentricity and the armature magnetic reaction harmoniccontent range. The obtained results are validated by 3D FEA.This latter is extended to the PM eddy current loss densitymapping and loops considering a given range of the armaturemagnetic reaction harmonic content.