ADAPTIVE VIRTUAL AUTOBALANCING FOR A RIGID ROTOR WITH UNKNOWN MASS IMBALANCE SUPPORTED BY MAGNETIC BEARINGS

The objective of this paper is to describe an imbalance compensation s cheme for a rigid rotor supported by magnetic bearings that performs o n-line identification of rotor imbalance and allows imbalance cancella tion under varying speed of rotation. The proposed approach supplement s existing magnetic bearing controls which are assumed to achieve elas tic suspension of the rotor. By adopting a physical model of imbalance and utilizing measurements of the spin rate, the proposed algorithm a llows the computation of the necessary corrective forces regardless of variations in the spin rate. Convergence of the algorithm is analyzed for single-plane balancing, and is supported by simulation in single- and two-plane balancing, as well as by experimental results in single- plane implementation.