Magnetic Bearing with Uniaxial Control Using Magnetic, Electrodynamic and Electromagnetic Levitation (original) (raw)
Magnetic bearings use magnetic force to sustain loads without any contact between the rotor and the bearing, therewith there is no friction or wear. Due to these advantages, these bearings are applied in wide range of applications, from flywheel energy storage systems to artificial hearts. In the first, the magnetic bearing reduces energy loss by friction, raising the performance, and in the second, the magnetic bearing minimizes the damage to blood cells. Many types of magnetic bearings are known, each one based on different levitation techniques, e.g. based on the use of superconductive materials. However, the superconductivity is obtained only at temperatures around 100 K, imposing limitations for practical applications at room temperature. A more promising technique is the electrodynamic levitation at room temperature. The repulsion force for the levitation is generated by the relative movement between a magnetic field and a conductor. The inconvenient of this technique is that ...
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