Fault-Tolerant Control of Magnetically-Levitated Rotor with Redundant Structures Based on Improved Generalized
Baixin Cheng1,2, Xin Cheng1,2, Shao Song3
1School of Mechanical & Electronic Engineering, Wuhan University of Technology, Wuhan 430070, China.
Sensors (Basel, Switzerland)
|August 28, 2021
Summary
This study enhances fault-tolerant control for redundant magnetic bearings by improving electromagnetic force (EMF) model accuracy. The proposed strategy with displacement compensation boosts disturbance rejection and rotor robustness in magnetically levitated systems.
Area of Science:
- Mechanical Engineering
- Control Systems Engineering
Background:
- Fault tolerance is crucial for magnetic bearing reliability.
- Redundant magnetic bearings offer a path to fault-tolerant control.
- Accurate electromagnetic force (EMF) modeling is vital for controller design.
Purpose of the Study:
- To improve the accuracy of the EMF model for redundant magnetic bearings.
- To develop a fault-tolerant control strategy incorporating displacement compensation.
- To enhance the disturbance rejection and robustness of magnetically levitated rotor systems.
Main Methods:
- Improved EMF model accuracy for an eight-pole symmetrical radial magnetic bearing.
- Calculation of displacement compensation matrices for coil failures.
- Development of a fault-tolerant control strategy with displacement compensation.
- Establishment of a rigid body dynamics model for the rotor system.
- Simulation analysis comparing the proposed strategy with and without displacement compensation.
Main Results:
- The improved EMF model enhances accuracy in redundant magnetic bearing systems.
- Calculated displacement compensation matrices effectively address coil failures.
- Simulations show the proposed fault-tolerant control strategy improves disturbance rejection.
- The strategy enhances the overall robustness of the rotor system.
Conclusions:
- The proposed fault-tolerant control strategy with displacement compensation significantly improves the performance of redundant magnetic bearings.
- Accurate EMF modeling and displacement compensation are key to achieving robust fault tolerance.
- This approach enhances the reliability and stability of magnetically levitated rotor systems under fault conditions.
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