Sliding Mode Control Based on Linear Quadratic Regulator for an Active Magnetic Bearing Flexible Rotor Virtual Collocated System

For an active magnetic bearing (AMB) flexible rotor system, a sliding mode control (SMC) method based on linear quadratic regulator (LQR) was proposed in this paper. The finite model of a flexible rotor system was developed. In order to deal with the non-collocation between the sensors and the bearings, a state observer by using state space method is used to estimate displacements at active magnetic bearings' locations with the displacements at corresponding sensors' locations. Furthermore, a sliding mode controller was designed for this multiple-input and multiple-output (MIMO) virtual collocated system. The optimal gain matrix of the state observer and the sliding mode controller's parameters were solved by linear quadratic regulator method. Finally, simulation analysis results of static and dynamic performance shown that the method proposed in this paper was effective.