Magnetic suspension systems offer advantages such as low noise, elimination of oil lubrication systems and seals, tunable stiffness and damping, and the ability to operate at higher speeds than rolling element or fluid-film bearings. Foster-Miller has developed both active and passive systems for all types of machinery, from flywheel energy storage systems to steam turbine generators and blood pumps. Passive magnetic bearings use opposed pairs of permanent magnets on the rotor and stator to establish the bearing's stiffness. Inherently simple, these bearings do not require any shaft position sensors or an electronic controller for operation.  Active magnetic bearings offer higher load-carrying capability and can accommodate higher temperatures. Their electronic controllers tune bearing stiffness and damping properties "on the fly," allowing for adjustments to system dynamics that affect resonant frequencies and reduce transmitted vibration.

In a recent project, Foster-Miller developed a cone-shaped design that combines radial and axial support into a single active magnetic bearing. This new type of magnetic suspension system will greatly enhance machinery performance, allowing higher speeds with enhanced rotor support. 

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