Abstract：This paper presents a method for analyzing the eddy current fields and resultant losses in the insulation fault zone of laminated iron core which occur the insulated faults. It is based on the finite-element method which uses the three-dimensional magnetic scalar potential magneto dynamic T, ψ-ψ formulation and a newly developed homogenization method is applied to model the laminations with the insulated faults effectively. In order to compute fields at various frequencies, the formulas for the effective skin depths along different directions in the anisotropic solid core are derived, which are accompanied with the adaptively generated finite-element meshes. As an example of application of the method developed above, the eddy current and associated losses in a large asynchronous machine core with insulated faults are computed over a very wide frequency range. The calculations results, based on the homogenization model by introducing anisotropic conductivity and on the direct method involving the actual description of lamination, respectively, are analytical comparison. The results of the comparison display the stator faults analyzed by the continuum model with the anisotropic conductivity can satisfy the actual accuracy requirement at low frequencies.
孟大伟,肖利军,徐永明,孟庆伟. 多频情况下存在绝缘故障的叠片铁心的涡流及涡流损耗的分析[J]. 电工技术学报, 2015, 30(6): 92-98.
Meng Dawei,Xiao Lijun,Xu Yongming,Meng Qingwei. Analysis of Eddy Current and Associated Losses Insulated Faults Involved in Laminated Iron Core Under Various Frequencies. Transactions of China Electrotechnical Society, 2015, 30(6): 92-98.
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