Abstract Fractional-slot Windings Permanent Magnet Synchronous Linear Motors (FW-PMSLM), which possess the merits of low cogging force, small thrust ripple, short end windings, low copper consumption and low power losses, are especially suitable for the long stroke transportation and accurate drive system. The multilayer analytical model of a FW-PWSLM prototype with 16 poles and 15 slots is presented based on the expressions of winding current distribution and the body current density equivalence of magnet. The magnetic fields of FW-PWSLM generated by winding current and permanent magnet are analyzed and calculated according to the analytical flux formulas of air-gap field and permanent magnet field derived by the Fourier series. The distributed Carter coefficient function is proposed to consider the slotting effect of primary core on the magnetic field. The results of the proposed analytical model are compared with finite element analysis results to verify the validity of the proposed modeling method. The electromagnetic force calculation errors of proposed method are compared by different pole arc coefficient and primary tooth width. Experimental thrust result on a prototype is presented and compared with the proposed analytical model by different airgap lengths. This paper provides the references for magnetic field calculation and optimization of the FW-PMSLM.
Xiaozhuo Xu,Xudong Wang,Haichao Feng等. Magnetic Field Calculation of the Permanent Magnet Synchronous Linear Motor With Fractional-slot Concentrated Windings[J]. Transactions of China Electrotechnical Society, 2015, 30(14): 122-129.
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2015, Vol. 30 
