Principle of Radial Suspension Force Generation and Control System Simulation for a Bearingless Brushless DC Motor

The dynamic decoupling control among electromagnetic torque and radial suspension forces is the basic condition of stable operation for a bearingless brushless DC motor. In the paper, the generation principle of radial suspension forces is expounded, mathematical models of electromagnetic torque and radial suspension forces are deduced. A control system based on rotor field oriented control method is designed and then simulated with Matlab/Simulink. The simulation results show that the torque and radial suspension force subsystems can be controlled independently, the validity of the proposed control method is verified, and the whole control system has good static and dynamic performance.