Active Magnetic Bearing Design and Backstepping-Adaptive Control for High-Speed Rotors

Abstract

Abstract Friction and vibrations hindering high-speed are the most pertinent problems facing the rotating machines. Thus, friction and vibration attenuation are essential in improving the overall performance of turbomachines. Conventionally, high-speed flywheel energy storage systems use Active Magnetic Bearings (AMB) to nullify friction losses and to deal with unbalances but, in the present era with increasing demand for high-speed machinery, the applications of AMBs are proliferating. They are not like the traditional bearings; they generate forces through magnetic fields with no contact between bearing and rotor thus decreasing the friction and providing the ability to counteract imbalances actively. This paper investigates an optimized design methodology along with backstepping adaptive control design of an 8-pole radial AMB used for flywheel energy storage systems. Design optimization using GA, along with analytical design constraints are presented. The design details along with finite element simulations are given to verify the optimization results and system requirements. Bearing parameters then obtained are used to develop a linearized mathematical model of the system, an adaptive back-stepping controller is designed for it to regulate the deviation of the rotating shaft from its equilibrium position.