The Design And Control Technology Study Of Active Magnetic Bearing

Active magnetic bearing (AMB) is one of the typical mechatronic products and a new type of high performance bearing which suspends the rotor in a contact-free manner. Since it has many advantages, such as no mechanical contact, no friction, lower power consumption, lasting service life and without environmental pollution, it has been paid more and more attention in energy resource, aerospace, communication, mechanical industry, robot and medical equipment. AMB is an integrated system including magnetic, electronics, magnetic, computers. Considering the above factors, the author works on the analysis and research of each section of AMB, including:Firstly, a single freedom mathematics model and the four degree of freedom state equation of AMB are founded based on the analyzing the principle of AMB; Secondly, a suspension experiment of one degree of freedom AMB is executed based on the analog control system and the digital control system, and the rotor's quick adjusting and steady levitating are examined; Thirdly, the rotor system with a variable parameter PID controller and sliding mode variable structure controller (SMC) is designed and simulated. The simulation results show that the control performance of the variable parameter PID controller is better than that of the conventional PID controllers, and sliding mode variable structure controller has high tracking precision and good robustness; Finally, an AMB experimental system was designed and implemented, the experiment results indicate that the digital controller can be debugged easily and works steadily with lower noise and better performance (static position error less than 2.2 μm).