Suspension Force Error Source Analysis and Multidimensional Dynamic Model for a Centripetal Force Type-Magnetic Bearing

2020 ◽  
Vol 67 (9) ◽  
pp. 7617-7628 ◽  
Author(s):  
Weiyu Zhang ◽  
Ling Cheng ◽  
Huangqiu Zhu
2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Yujiang Qiu ◽  
Shuyun Jiang

Developing a flywheel energy storage system (FESS) with permanent magnetic bearing (PMB) and spiral groove bearing (SGB) brings a great challenge to dynamic control for the rotor system. In this paper, a pendulum-tuned mass damper is developed for 100 kg-class FESS to suppress low-frequency vibration of the system; the dynamic model with four degrees-of-freedom is built for the FESS using Lagrange's theorem; mode characteristics, critical speeds, and unbalance responses of the system are analyzed via theory and experiment. A comparison between the theoretical results and the experiment ones shows that the pendulum-tuned mass damper is effective, the dynamic model is appropriate, and the FESS can run smoothly within the working speed range.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Peiling Cui ◽  
Jian Cui ◽  
Qian Yang ◽  
Shiqiang Zheng

Double-gimbal magnetically suspended CMG is a novel attitude control actuator for the agile maneuver spacecraft. Taking the double-gimbal magnetically suspended control moment gyro used on agile maneuver spacecraft as the research object, the dynamic model of the magnetically suspended rotor, the inner gimbal, and the outer gimbal of double-gimbal magnetically suspended control moment gyro is built. The nonlinear coupling characteristic between the rotor, the gimbal, and the spacecraft is given. It can be seen that the motion of magnetically suspended rotor does not only rely on magnetic bearing force but also suffer from the influence of gimbal servo system and spacecraft motion. The coupling torque includes the gyro coupling torque and the inertial coupling torque. The work in this paper provides the foundation for further studies.


Author(s):  
Zhe Sun ◽  
Xiao Kang ◽  
Jingjing Zhao ◽  
Guojun Yang ◽  
Zhengang Shi

Magnetic bearings are widely applied in High Temperature Gas-cooled Reactor (HTGR) and auxiliary bearings are important backup and safety components in AMB systems. The dynamic analysis of the AMB rotors touchdown process is an important foundation for designing auxiliary bearings. In this paper, a data-based dynamic analysis of the touchdown process is proposed. The dynamic model of the touchdown process is firstly established and then the nonlinear extended Kalman filtering technique is applied. Based on the dynamic model and Kalman filtering technique, the proposed method can offer estimations of rotor’s displacements, velocities and accelerations from noisy observations. The proposed method is validated by the experiment data from touchdown experiments. The touchdown experiments are performed on an experimental system with a 440kg heavy rotor, the rotational speed in the experiments is 5000RPM and no brake is applied.


2011 ◽  
Vol 109 ◽  
pp. 199-203
Author(s):  
Wei Wei Zhang

To investigate the active magnetic bearing-rotor system which is influenced by the base motion, coupled dynamic model is developed in this paper. The effects of base motion, electrical differential equations of control system and the mounting of sensors at different positions on the dynamic characteristics of the magnetic bearing-rotor system were discussed. The feasibility of the dynamic model is illustrated. This dynamic model can be used for the coupled electromechanical dynamics analysis of rotor system equipped with magnetic bearings.


2017 ◽  
Vol 2017 ◽  
pp. 1-11
Author(s):  
Zhe Sun ◽  
Xunshi Yan ◽  
Jingjing Zhao ◽  
Xiao Kang ◽  
Guojun Yang ◽  
...  

Magnetic bearings are widely applied in High Temperature Gas-cooled Reactor (HTGR) and auxiliary bearings are important backup and safety components in AMB systems. The performance of auxiliary bearings significantly affects the reliability, safety, and serviceability of the AMB system, the rotating equipment, and the whole reactor. Research on the dynamic behavior during the touchdown process is crucial for analyzing the severity of the touchdown. In this paper, a data-based dynamic analysis method of the touchdown process is proposed. The dynamic model of the touchdown process is firstly established. In this model, some specific mechanical parameters are regarded as functions of deformation of auxiliary bearing and velocity of rotor firstly; furthermore, a machine learning method is utilized to model these function relationships. Based on the dynamic model and the Kalman filtering technique, the proposed method can offer estimation of the rotor motion state from noisy observations. In addition, the estimation precision is significantly improved compared with the method without learning. The proposed method is validated by the experimental data from touchdown experiments.


2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Xiaofan An ◽  
Ning Li ◽  
Peng Zhang ◽  
Wenbo Sun

The approximate assumptions of limit equilibrium methods are the fundamental cause of the deviation between their calculation results and actual situation. This study proposes a new finite-element evaluation method to reflect the progressive failure characteristics of rock slopes. By comparing the results of limit equilibrium and finite-element methods, the influence factors of stability for planar landslides are systematically studied. The factors include the plastic parameters of sliding surfaces in progressive failure, the elastic parameters of sliding mass, the elastic deformation of sliding beds, and excavation stress release. Moreover, the stress distribution rules on sliding surfaces and the diversity of safety factors are explored. Finally, the error source and calculation accuracy of the limit equilibrium method in slope analysis are obtained. The study provides scientific references for analyzing and evaluating the stability of such slopes.


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