Chillers using the variable speed oil free multiple centrifugal compressors with
magnetic bearings offer a rated efficiency in the range of 0.33 to 0.37 kW/tonne (integrated part load value/IPLV).
Stability analysis of self-sensing
magnetic bearing controllers.
Therefore,
magnetic bearings are preferred for large engines operating at high loads and relatively lower speed, while the opposite is true for foil bearings.
Chiba, "A vibration reduction method of one-axis actively position regulated single-drive bearingless motor with repulsive passive
magnetic bearings," IEEE Transactions on Industry Applications, vol.
Shimizu, "Development of super- conducting
magnetic bearing for 300 kW flywheel energy storage system," IEEE Transactions on Applied Superconductivity, Vol.
Magnetic bearings have replaced the standard antifriction bearings or hydrodynamic bearings which permit the single shaft to rotate at speeds significantly higher than the 12,000 rpm range which was once considered near the upper practical limit of centrifugal compressor speed.
The traditional influence coefficient method for controlling flexible spindle rotor vibration needs to calculate the electromagnetic force by solving the multivariate system, which causes the number of vibration suppression nodes to be not more than the number of excitation nodes of the active
magnetic bearing. In order to solve the above problem, the paper puts forward the optimal influence coefficient control method with weights for multinode unbalanced vibrations of flexible electric spindle rotors, which uses all the unbalanced vibration nodes of the whole spindle as the control objective function to achieve the optimal control of multinode unbalanced vibration.
Shi, "Dynamic behavior analysis of touchdown process in active
magnetic bearing system based on Kalman filtering," in Proceedings of the 2014 22nd International Conference on Nuclear Engineering, ICONE 2014, July 2014.
As part of this agreement, GE Oil & Gas will make use of SKF's
magnetic bearing technologies from front-end engineering design to installation, testing and service to customers.
Where
magnetic bearing systems are used the addition of monitoring equipment means that they can be actively assessed to reduce maintenance costs and downtime.
Both the fans utilise an ultra-low friction
magnetic bearing that provides high airflow and high static pressure along with keeping a check on the fan noise.