Research On High-accuracy Control Technology Of Active Magnetic Suspension System In TFG

The Three-Float Gyroscope motor is supported by dynamic pressure air-bearing,the float assembly is supported by liquid-bearing and assisted by magnetic suspension.The application of magnetic suspension in electromechanical gyroscope directly improves the supporting environment of the output axis of gyroscope,eliminates the mechanical contact between the float assembly and the gyroscope shell to a great extent,stabilizes the position of the centroid of the float,and thus greatly improves the accuracy of the gyroscope.In this paper,aiming at the active magnetic suspension control system of TFG,the influence of different control methods on the system is studied and analyzed,and the simulation analysis and experimental verification are carried out.And study the motion law of the gyro float in the axial and radial direction under different working conditions.Firstly,based on the working principle of the TFG and the structure of the magnetic suspension system,the force-adding mechanism of the active magnetic levitation system is analyzed,and the mechanical model of the system is studied.Based on the differential equation of motion of a rigid body,the dynamic relationship of the 5 degrees of freedom of the float and the equation of state of the motion of the float are established,and the motion law of the float under four typical external actions is simulated and analyzed.Secondly,aiming at the problem of output feedback caused by coupling,the state decoupling feedback control of active magnetic suspension control system is carried out.The state feedback adjusts the control parameters more flexibly.The simulation results show that the state feedback system can effectively increase the system stiffness and reduce the magnetic levitation force.On the basis of state feedback,classical PID controllers are designed for each channel.Because the classical control parameters can't be adjusted with the system state,it is often difficult to achieve the optimal control effect,so a fuzzy PID controller is designed.The control parameters can be adjusted online by using the fuzzy PID controller,and the advantages of the fuzzy control are verified by simulation.Finally,on the basis of simple analysis of the principle and function of each component of the active magnetic suspension hardware circuit,a fuzzy PID control algorithm is designed on the test platform of a certain type of TFG.The feasibility of the algorithm is verified by the test of the control algorithm.The results show that the fuzzy and state feedback can be used.