Calculation of Air Gap Electromagnetic Field of High-Speed Magnetic Levitation Linear Motor Based on Equivalent Current Layer

The linear synchronous motor (LSM) realizes energy conversion based on the air gap magnetic field between the stator and rotor, and the air gap magnetic field distribution directly affects the performance of the motor, which in turn has an impact on the operation of the electromagnetic suspension (EMS) maglev system. In order to study the air gap magnetic field distribution of the linear motor, the analytical expression of air gap magnetic density of LSM considering the open structure, cogging effect and harmonic influence was deduced based on electromagnetic field theory and the equivalent current layer model. To reshape the stator and rotor excitation source, the equivalent current sheets are calculated by Fourier series expansion. And the equivalent current sheets are placed in the motor cogging layers when the equivalent current layer model is constructed. The accuracy of the proposed method is verified by comparing the results with the finite element solution.