Optimal Design of High-Speed Double-Sided Linear Permanent Magnet Motors With Segmented Trapezoidal Magnetic Poles

Abstract

For the kilometer-level electromagnetic launch system, a high-speed double-sided linear permanent magnet (PM) linear motor is presented in this paper. To enhance the average thrust force, reduce the thrust ripple and normal force of linear motor, a segmented trapezoidal PM shaping method is proposed. Compared with conventional PM shaping method, the segmented trapezoidal PMs achieves less force ripple, greater average force and lower manufacturing difficulty. The risk of PM demagnetization fault has been taken into account. To reduce the losses in the mover of the linear motor, a non-metallic light-weight mover structure is proposed. The effectiveness of segmented trapezoidal PMs and non-metallic light-weight mover are verified by the finite element method and experiment.

Keywords

• Electromagnetic launch system
• permanent magnet linear motors
• permanent magnetic shaping method
• optimal design