Detent Force Analysis and Optimization for Vertical Permanent-magnet Linear Synchronous Motor with Fractional-slot Windings

This paper investigates the detent force modeling and optimization of a iron-core type 16-pole 15-slot permanent magnet linear synchronous motor (PMLSM) for ropeless elevator applications. Variable network non-linear magnetic equivalent circuit (VNMEC) model is established to predict the detent force of PMLSM. The topology structure of equivalent magnetic circuit is developed and the permeance are derived and calculated. The end effect of two end teeth is essential for detent force analysis and it is focused in the modeling. Magnetic saturation of primary tooth also is taken into account and nonlinear permanence is calculated. Some 3-D finite-element numerical calculations are used to validate the feasibility of the proposed method. Then proposed VNMEC is employed to calculate and optimize the detent force considering the end tooth dimensions. In final, experimental results are further used to verify the validation of proposed model.