Research on Magnetic Levitation Bearing Control Based on Fuzzy Fractional-Order PID
摘要
The magnetic levitation bearing system is difficult to achieve an effective balance between dynamic response speed and stability with the traditional integer-order proportional-integral-derivative (PID) controller due to its inherent strong nonlinearity, open-loop instability, time-varying characteristics of the model parameters, and high sensitivity to unknown external perturbations. In this paper, an improved control strategy based on Fuzzy Fractional-Order PID (Fuzzy FOPID) control is proposed. Firstly, the mathematical model of the magnetic levitation bearing is established, the theory of fractional-order calculus and its advantages in the design of PID controllers are elaborated, and the theoretical basis and working principle of Fuzzy FOPID control are analyzed; based on this, the simulation and analysis of the control system are carried out, which verifies the superiority of the proposed control strategy in comparison with the integer-order PID; finally, in order to fully verify the practical effectiveness of the control strategy, a static levitation control strategy is carried out on an experimental platform. Finally, in order to fully verify the effectiveness of the control strategy, static levitation test, robustness test with external excitation interference, and stability test under high-speed rotating conditions are carried out on the experimental platform. The simulation and experimental results show that the control algorithm can improve the dynamic performance and steady-state accuracy of the system, and has strong robustness.