The Movement Stability Study Of Flywheel Rotor System Supported By Active Magnetic Bearing

Flywheel energy storage technology is a new energy storage technology with advantage of high energy storage density,good continuous performance,high energy conversion efficiency,long service life and good environmental friendliness.Based on the research and application of flywheel energy storage technology and 600 Wh experimental prototype,the structure and movement stability of flywheel rotor system in flywheel energy storage system are studied majorly.According to the structural characteristics of the flywheel rotor system and the motion characteristics of the high speed rotor,the impact factors of the movement stability of the flywheel rotor system are analyzed.Based on experiments,the relationship between the dynamic balance of the design requirements and the speed,eccentricity and centrifugal force of the flywheel rotor system is analyzed.By analyzing the vortex motion phenomenon and the gyroscopic effect phenomenon of the high speed rotor,the impacts of the movement stability are elaborated.Based on the supporting characteristics of the AMB(Active Magnetic Bearing)in the flywheel energy storage system,the rigid kinetics model and the structural support mechanics model of the flywheel rotor system are established.The impact of the equivalent stiffness and equivalent damping of the active magnetic bearing in the cross feedback control method are analyzed to inhibit the gyroscopic effect.Aiming at the relationship between the axial magnetic bearing and the radial magnetic bearing on the movement attitude control of the flywheel rotor system,the coupling mechanical equations are established.According to the influence of coupling effect on the movement stability of the flywheel rotor system,the physical parameters of the axial magnetic bearing and the structural parameters of the flywheel rotor system are analyzed by simulation,and the structure of the axial magnetic bearing is optimized.The vibration characteristics of the flywheel rotor system under different rotational speeds are studied.In addition,the main factors influencing the axial and radial movement stability of the flywheel rotor system are analyzed.Based on the experimental data,The interference of different frequency range is classified and compared and the influence on the stability of flywheel rotor system is analyzed.Through the analysis of experimental phenomena,which the unbalanced response amplitude of the upper radial active magnetic bearing is smaller than the lower radial active magnetic bearing,the position of the thrust disc and the axial magnetic bearing system of the flywheel rotor system is optimized with considering the support of the rotor gyroscopic effect.The structural mechanical properties of the flywheel rotor model are simulated and compared to optimize the flywheel rotor system.