Magnetic bearings are capable of supporting loads using the principle of magnetic levitation. This inherently unstable system is used in conjunction with various forms of feedback control that allow the bearing to remain levitated, and centered within its housing, even while spinning and/or carrying a load. By eliminating physical contact between moving parts, magnetic bearings are impervious to mechanical wear, resulting in rotary systems that do not suffer from energy losses due to friction. Such benefits extend the usefulness and feasibility of rotor systems to wider applications than before. While magnetic bearing systems are advantageous when compared to traditional mechanical bearings, they are accompanied by several challenges. One of the core challenges is to reject disturbances due to mass imbalances within the levitated rotor as well as added broadband disturbances while spinning at high speeds.
The MBC500 is a good Multi-Input Multi-Output (MIMO) testbed for controls research and is used as the experimental platform for Professor Tsao’s Advanced Mechatronics graduate class (MAE 277). Students perform a system identification of the system and create advanced controllers for it (e.g., repetitive controllers, state observers, minimum variance).