For the purpose of high speed rotation and clean operation without contact between rotor and bearing surface, an active controlled D.C. magnetic bearing has been studied. In this work, the main object is to design a magnetic bearing system and to test its characteristics.
Magnetic bearing system is composed of one radial magnetic bearing with four electromagnets. To reduce eddy current loss, the rotor and stators are made of laminated silicon steel sheets. Two gap sensors are used to measure vertical and horizontal rotor displacement. Gap sensor signal is changed to control signal by controller to stabilize magnetic bearing system. A proportional and derivative control circuit is employed to suspend rotor safely.
Stiffness and running accuracy of PID controlled magnetic bearing system is better than PD controlled one.
