An Active Magnetic Damper Concept for Stabilization of Gas Bearings in High-Speed Permanent-Magnet Machines

The successful application of ultrahigh-speed electrical-drive systems in industrial products is currently limited by lacking high-speed bearing technologies permitting high reliability and long lifetime. Promising bearing technologies for high rotational speeds are contactless bearing concepts such as active magnetic bearings or gas bearings. While magnetic bearings usually are major electromechanical systems with substantial complexity, gas bearings allow compact realizations with high load capacity and stiffness; however, poor dynamic stability has been limiting their use at high rotational speeds. Following a hybrid bearing approach with an aerodynamic gas bearing for load support, a small-sized active magnetic damper concept is proposed to enable the stable high-speed operation of the gas bearing with a minimum of additional complexity and costs. As for the effective stabilization of the gas bearing, a high-quality displacement measurement is essential, and a new eddy-current-based rotor-displacement self-sensing concept employing an auxiliary signal injection and rotor displacement measurement circuit is presented. A hardware implementation of the proposed concept is shown providing high-resolution measurement signals.

[1]  J. W. Kolar,et al.  Analysis and design of an ultra-high-speed slotless self-bearing permanent-magnet motor , 2012, IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society.

[2]  Daejong Kim,et al.  Five Millimeter Air Foil Bearing Operating at 350,000 RPM in a Micro Electric Motor Drive , 2011 .

[3]  Y. Perriard,et al.  Analysis and comparison of classical and flex-PCB slotless windings in BLDC motors , 2012, 2012 15th International Conference on Electrical Machines and Systems (ICEMS).

[4]  Jan Peirs,et al.  Aerodynamic journal bearing with a flexible, damped support operating at 7.2 million DN , 2010 .

[5]  J.W. Kolar,et al.  Megaspeed Drive Systems: Pushing Beyond 1 Million r/min , 2009, IEEE/ASME Transactions on Mechatronics.

[6]  F. Al-Bender,et al.  600 000 rpm Electrical Motor/Generator Supported by Air Bearings , 2012 .

[7]  C. Zwyssig,et al.  Analysis and Measurement of Three-Dimensional Torque and Forces for Slotless Permanent-Magnet Motors , 2012, IEEE Transactions on Industry Applications.

[8]  Yves Perriard,et al.  Very-High-Speed Slotless Permanent-Magnet Motors: Analytical Modeling, Optimization, Design, and Torque Measurement Methods , 2010, IEEE Transactions on Industrial Electronics.

[9]  James F. Walton,et al.  Operation of a Mesoscopic Gas Turbine Simulator at Speeds in Excess of 700,000rpm on Foil Bearings , 2007 .

[10]  Johann W. Kolar,et al.  Half-Controlled Boost Rectifier for Low-Power High-Speed Permanent-Magnet Generators , 2011, IEEE Transactions on Industrial Electronics.

[11]  B. J. Hamrock,et al.  Optimization of self-acting herringbone journal bearings for maximum stability , 1974 .

[12]  James F. Walton,et al.  Operation of a Mesoscopic Gas Turbine Simulator at Speeds in Excess of 700,000 rpm on Foil Bearings , 2004 .

[13]  John H. Vohr,et al.  Characteristics of Herringbone-Grooved, Gas-Lubricated Journal Bearings , 1965 .

[14]  Johann W. Kolar,et al.  PEEC-Based Numerical Optimization of Compact Radial Position Sensors for Active Magnetic Bearings , 2008 .

[15]  Jiancheng Fang,et al.  AMB Vibration Control for Structural Resonance of Double-Gimbal Control Moment Gyro With High-Speed Magnetically Suspended Rotor , 2013, IEEE/ASME Transactions on Mechatronics.

[16]  G. Schweitzer,et al.  Magnetic bearings : theory, design, and application to rotating machinery , 2009 .

[17]  J. Kolar,et al.  Efficiency Optimization of a 100-W 500 000-r/min Permanent-Magnet Machine Including Air-Friction Losses , 2007, IEEE Transactions on Industry Applications.

[18]  Aly El-Shafei,et al.  Controlling Journal Bearing Instability Using Active Magnetic Bearings , 2007 .

[19]  T. Kuwajima,et al.  An estimation of the rotor displacements of bearingless motors based on a high frequency equivalent circuits , 2001, 4th IEEE International Conference on Power Electronics and Drive Systems. IEEE PEDS 2001 - Indonesia. Proceedings (Cat. No.01TH8594).

[20]  Ralph M. Burkart,et al.  Analysis and Design of a 300-W 500 000-r/min Slotless Self-Bearing Permanent-Magnet Motor , 2014, IEEE Transactions on Industrial Electronics.

[21]  Jong Hyun Kim,et al.  Design and Manufacturing of Mesoscale Tilting Pad Gas Bearings for 100–200 W Class PowerMEMS Applications , 2009 .

[22]  A. Looser,et al.  A hybrid bearing concept for high-speed applications employing aerodynamic gas-bearings and a self-sensing active magnetic damper , 2011, IECON 2011 - 37th Annual Conference of the IEEE Industrial Electronics Society.

[23]  Pierre-Daniel Pfister Very high-speed slotless permanent-magnet motors , 2010 .

[24]  Jan Abraham Ferreira,et al.  On the Speed Limits of Permanent-Magnet Machines , 2010, IEEE Transactions on Industrial Electronics.

[25]  Hannes Bleuler,et al.  New results for self-sensing active magnetic bearings using modulation approach , 2005, IEEE Transactions on Control Systems Technology.

[26]  Akira Chiba,et al.  Performances of bearingless and sensorless induction motor drive based on mutual inductances and rotor displacements estimation , 2006, IEEE Transactions on Industrial Electronics.