Analysis and Modeling for Magnetically Levitated Actuator With End-effects

The end-effect of Halbach array affects the accuracy of the magnetic levitation (maglev) motor force model. This paper presents a general semi-analytical method to solve the magnetic force and torque considering the magnetic field end-effects in the whole 2-D plane. The new Fourier period of the Halbach array is defined according to the distance between the positions where the magnetic field decays to zero, and then an analytical magnetic field model of the array including the end-distorted area is derived by the new Fourier series and Maxwell equations. Benefited from the Gaussian quadrature, the complex Lorentz integral of the force and torque can be simplified into the form of summation while the high computation accuracy is still promised. Finally, taking the typical maglev planar motor introduced in the paper as an example, a prototype of the motor is manufactured, and the experiment is conducted to validate the proposed semianalytical method. Compared with the existing harmonic model, the force and torque predicted by the semi-analytical model are closer to the measurement results, and the decoupling results of the force and torque in all directions are more accurate based on the proposed model.