Average power balance method for power failure compensation control of high-speed turbo molecular pump with AMB system

摘要

High-speed permanent magnet motors supported by an active magnetic bearing (AMB) have been widely used in the industrial field. However, the AMB-rotor system will lose its magnetic force if the mains power fails, and high-speed rotor will crash the stator severely and bring a fatal damage to the system. To solve this problem, a power failure compensation control method based on the average power balance control was proposed. Firstly, a motor energy feedback model was proposed. Secondly, a non-linear controller with double closed loops was designed. And the Lyapunov function was built and analysed to ensure the system stability. Finally, a series of experiments based on the high-speed magnetically suspended vacuum turbo molecular pump was carried out. The experiment results verified the validity and feasibility of the proposed method, and the safety of the AMB system was improved greatly.