Decoupling control of bearingless synchronous reluctance motor based on inverse system method

The principle of a bearingless synchronous reluctance motor (BSRM) is introduced and the mathematical model of control system is deduced. As the BSRM is a multi-variable, nonlinear and strongly coupled system, the main problem of the control system is the couplings among the electromagnetic torque and the two radial force components in the x- and the y-axis. A decoupling method based on α-order inverse system is designed to decouple those variables. Using α-order inverse system method, the complex controlled object is decoupled into two second-order linear subsystems and one first-order linear subsystem. The linear system theory is used to design the closed-loop linear regulators, and the dynamic and static performance of the system can be improved. Simulation has been carried out and the simulation results show that good static and dynamic decoupling performance can be achieved using the proposed method.