Abstract：A homogenization method is presented to compute the eddy current and associated loss in stator core which hold the interlamination short-circuits based on the finite element method at low frequency. The direct modeling method needs a fine mesh within each sheet and consequently results in large number of unknowns. To avoid modeling individually each sheet, a continuum model with an equivalent conductivity is used to substitute for a number of sheets. As an example of application of the method developed above, the eddy current and resultant losses in a large asynchronous machine core with interlamination short-circuit are computed by using the aid of a 3D finite-element packet which utilizes the T, ψ-ψformulation. The calculation, based on the continuum model by introducing anisotropic conductivity and on the real lamination model, respectively, are analytical comparison. The results of the comparison display the stator faults analyzed by the continuum model with the isotropic conductivity can satisfy the actual accuracy requirement.
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2014, Vol. 29 
