The Optimal Design of Real Time Control Precision of Planar Motor

In this paper, the Halbach permanent magnet array with 2 segments per pole is selected for analysis. The harmonics that the harmonic numbers for the lx and ly-direction in local coordinate system are equal to each other are set as a pair for transformation. Then the expressions of the magnetic flux density distribution of the Halbach array in global coordinate system are derived. The dimensions of the coil are parameterized. The force and torque exerted on the Halbach array by a coil are calculated by Lorentz force law. The first three harmonics are chosen for real time control by analyzing the ratio of each harmonic in the total harmonics. The harmonic model has good performance on torque by comparing with the models used before. As for the force, the errors can be significantly reduced by optimizing the parameterized dimensions of coil because of the cosine or sine form error figures. The optimized model has good precision on both force and torque. The same method can be applied on the Halbach permanent magnet array with different segments per pole.