The active vibration attenuation of a built-in motorized milling spindle.

An active vibration control scheme is proposed for suppressing the vibration of the high-speed induction electric spindle with a built-in force actuator to improve the performance of high-speed milling system. The built-in force actuator is a set of windings, which are added to the stator of electric spindle motor. An improved fast block least mean square (FBLMS) adaptive filter is adopted to produce the reference control force, which is used to obtain the control current of force actuator, and then a controlled, non-contact electromagnetic control force on the electric spindle is produced by the force actuator to control actively chatter, unbalanced vibration and disturbance signals of milling system. The built-in motorized spindles dynamic is modeled by means of the finite element method, the dynamic milling, the air gap excitation current of torque and radial electromagnetic control force are modeled, the control force coefficient and the unbalanced magnetic pull force coefficient are identified by finite element analysis, and then the active vibration control scheme for the flexible induction electric spindle is designed. The vibration, with a different frequency component, is investigated. The results show that the improved FBLMS adaptive filter and the proposed active control scheme have an obvious effect on suppressing the spindle chatter, unbalanced vibration and other frequency vibration components in the built-in motorized milling spindle. [ABSTRACT FROM AUTHOR]