Rotordynamic Response and Identification of AMB Machining Spindle

Active magnetic bearings (AMBs) are a very promising technology for machining applications. They offer a number of advantages compared to classical bearings, such as high speed capability, rotation accuracy, high stiffness, and possibility of active displacement tracking. This paper presents a modeling approach for a high-speed machining spindle-AMBs system based on finite-element model analysis coupled to experimental modal identification. The extracted frequency response functions, measured between the magnetic bearing journals and the sensor locations, are compared with the responses of a rotor model, and a calibration procedure is applied to reduce the discrepancies between the model and the measured data.