Unbalanced Magnetic Force Calculation for Assembly Jig Design

In this paper, four numerical formulas are introduced to calculate possible unbalanced magnetic forces (UMFs) during the assembly process in order to save calculation time and efforts. If the proposed formulas are used to calculate the UMFs according to the degree of rotor eccentricity every time the rotor position is changed relative to the stator position in the axial direction, a fully configured or partial 2-dimensional (2-D) model and 3-D periodic analysis model are used for magnetic field calculation instead of a fully configured 3-D analysis model. The reliance of the formulas is verified by comparing the results calculated by the formulas with each other. Then, the size and the number of guide bars as assembly jigs are selected considering the calculated UMFs.