Comparing Geometries for Magnetic Bearings

Most Active Magnetic Bearings (AMBs) show a symmetry of 4 geometry, because the magnetic forces are generated in 4 points in a plane, two in the canonical x direction and two in the y direction. AMBs with symmetry of 3 are harder to find, either in real-world applications or in the specific literature. Their stators generate forces in 3 coplanar points; one of these, at most, can lie in one of the canonical x,y directions. This work will develop and analyse mathematical models for the symmetry of 3 AMBs; in some cases these models can be problematic. Some comparisons will also be made between these two basic geometries trying to decide whether one or the other should be used in practical applications.