A METHOD AND A SYSTEM FOR DETERMINING ECCENTRICITY

摘要

A method for determining eccentricity of a machine reel comprises: monitoring (301) torque acting on the machine reel, producing (302) a torque signal representative of the torque as a function of time, and determining (303) from the torque signal a quantity proportional to an amplitude of an alternating torque component having a temporal cycle equal to a temporal cycle of revolution of the machine reel. The determined quantity is indicative of the eccentricity of the machine reel and can be used for controlling the rotational speed and/or the angular acceleration of the machine reel so as to avoid damages and fibre web breaks which otherwise might be caused by vibrations due to the eccentricity.