Magnetic Bearing Using Rotation Magnetized Direction Configuration

Passive magnetic bearing (PMB), made of high remanence rare earth permanent magnets, is brittle in nature; therefore, precautions must be taken to reduce the chances of vibration transmitting to the permanent magnets. In the present work, a rotation magnetized direction (RMD) structure made of aluminum ring and square shaped magnetic pieces has been proposed. A comparative study of load carrying capacities of sector magnets and square magnets has been presented. Three-dimensional (3D) Coulombian model was solved to estimate the load carrying capacity. Theoretical and experimental studies on the load carrying capacities of full ring magnet (more prone to cracking) and the proposed structure have been presented to prove the superiority of the proposed structure. In addition to load capacity, comparison between amplitudes of vibration at different frequencies, orbit plots, and time taken for breakage of the magnets at the resonance frequency has been presented.