In-situ Runout Identification in Active Magnetic Bearing System by Extended Influence Coefficient Method

In this study, an efficient, yet easy to use, in-situ runout identification scheme by using extended influence coefficient method is presented for active magnetic bearing systems. Advantages of the proposed scheme are that target runout is identified and compensated under given operating condition, and it does not require any extra sensor or device for measurement of runout. It is shown experimentally that the proposed scheme successfully identifies and eliminates the troublesome runout of the AMB system in the laboratory so that a high precision spindle system can be achieved, while it is in operation.