An unified approach to controls for unbalanced compensation in active magnetic bearings

This paper investigates the control for unbalanced compensation in active magnetic bearings from a viewpoint of output regulation. In an analytical study, the complex-variable description is used, which makes the manipulation of equations easier. A general form of the controller achieving displacement, current or force regulation is presented. The derived controllers in a complex-variable form are converted into two types of real-variable representations for actual implementation: the state equation and convolution integral. It clarifies the equivalence between the independently developed control methods