Modeling and Analysis of a Novel Contactless Magnetic Lock Equipped With Permanent Magnets for Aerospace Applications

This article presents analysis, design, and experiment of a novel contactless magnetic lock targeting aerospace applications. The magnetic lock eliminates the excitation windings and only permanent magnets (PM) serve as the magnetic field source, leading to improved thermal reliability. Analytical equations are derived for the torque characteristics of the magnetic lock using Norton's equivalent magnetic circuit and virtual-work method. And it is highlighted that the performance of the magnetic lock should be evaluated mainly in terms of the peak torque, critical angle, and locking area. The influences of the PM shape and size on the performance of the magnetic lock are then investigated in detail. It is shown that the rhombus magnet shape is preferred if judged from both the peak torque and torque density. The results are validated by 3-D numerical computations, and further verified by experimental measurements on a magnetic lock prototype.