Dynamic characteristics of the rotor in a magnetically suspended control moment gyroscope with active magnetic bearing and passive magnetic bearing

2014 ◽  
Vol 53 (4) ◽  
pp. 1357-1365 ◽  
Author(s):  
Jiqiang Tang ◽  
Biao Xiang ◽  
Yongbin Zhang
Keyword(s):  
Dynamic Characteristics ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Control Moment Gyroscope ◽  
Control Moment

Dynamic Analysis of Flexible Rotor Suspended by Active Magnetic Bearings With LQR Controller

2018 ◽  
Author(s):  
Yixin Su ◽  
Yanhui Ma ◽  
Qian Shi ◽  
Suyuan Yu
Keyword(s):  
Dynamic Characteristics ◽  
Beam Theory ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Flexible Rotor ◽  
Linear Quadratic ◽  
State Response ◽  
Lagrange’S Equation ◽  
Linear Quadratic Regulation ◽  
Lqr Controller

Dynamic characteristics of active magnetic bearing (AMB)-flexible rotor system are closely related to control law. To analyze dynamic characteristics of flexible rotor suspended by AMBs with linear quadratic regulation (LQR) controller, a simple and effective method based on numerical calculation of unbalanced response is proposed in this article. The model of flexible rotor is established based upon Euler-Bernoulli beam theory and Lagrange’s equation. Disc on the rotor and its Gyro effect are taken into account. LQR controller based on error and its derivative is developed to control electromagnetic force of AMB at each degree of freedom (DOF) in real time. Under the unbalanced exciting force, the steady-state response and transient response in time domain of each node of flexible rotor at 0–4000 rad/s are calculated numerically. The critical speeds of rotor are obtained by identification method quickly and easily.

Dynamic Characteristics of Sealed Squeeze Film Damper With a Central Feeding Groove

2005 ◽  
Vol 127 (1) ◽  
pp. 103-111 ◽  
Author(s):  
Keun-Joo Kim ◽  
Chong-Won Lee
Keyword(s):  
Dynamic Characteristics ◽  
Pressure Field ◽  
Dynamic Pressure ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Field Analysis ◽  
Squeeze Film ◽  
Test Rig ◽  
Squeeze Film Damper ◽  
Dynamic Coefficients

In this paper, the dynamic characteristics of an oil-lubricated, sealed squeeze film damper (SFD) with a central feeding groove are analytically derived based on an enhanced dynamic pressure field analysis, accounting for the effect of the seal and feeding grooves, and its validity is experimentally verified. A test rig using an active magnetic bearing system as an exciter is introduced to identify the dynamic characteristics of SFDs with high accuracy and efficiency. Experiments are conducted with the seal gap varied, in order to investigate its effect on the dynamic characteristics of the SFD. The estimated and analytical damping and inertia coefficients for the sealed SFD with a groove are compared and it is found that the pressure field analysis, when neglecting the effect of the seal groove, tends to far underestimate the SFD dynamic coefficients.

Coupled Dynamic Analysis of Magnetic Bearing-Rotor System under the Influences of Base Motion

2011 ◽  
Vol 109 ◽  
pp. 199-203
Author(s):  
Wei Wei Zhang
Keyword(s):  
Control System ◽  
Dynamic Analysis ◽  
Dynamic Model ◽  
Dynamic Characteristics ◽  
Magnetic Bearing ◽  
Rotor System ◽  
Active Magnetic Bearing ◽  
Dynamics Analysis ◽  
Coupled Dynamic Analysis ◽  
Electromechanical Dynamics

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.

Effects of the Magnetic Damper Locations on Dynamic Characteristics of the Active Magnetic Bearing System in Manufacturing Engineering

2012 ◽  
Vol 252 ◽  
pp. 51-55
Author(s):  
Zhen Yu Xie ◽  
Hong Kai Zhou ◽  
Xiao Wang
Keyword(s):  
Dynamic Characteristics ◽  
High Speed ◽  
Magnetic Bearing ◽  
Magnetic Bearings ◽  
Active Magnetic Bearing ◽  
Active Magnetic Bearings ◽  
Actual Operation ◽  
And Control ◽  
System Operating ◽  
Bearing System

The magnetic damper was introduced into the high speed rotating machinery to restrain the vibration of the rotor supported by active magnetic bearings. The experimental setup, which was made up of one rotor, two radial active magnetic bearings, one axial active magnetic bearing, one magnetic damper and control system, was built to investigate the effects of the magnetic damper locations on dynamic characteristics of the system by theoretical analysis, experimental modal analysis and actual operation of the system. The results show that the vibration of the active magnetic bearing system operating at the modal frequency can be reduced more effectively if the magnetic damper is located far from the nodes of the corresponding mode shape.

The Dynamics of a Cracked Rotor With an Active Magnetic Bearing

2001 ◽  
Author(s):  
Changsheng Zhu ◽  
David A. Robb ◽  
David J. Ewins
Keyword(s):  
Dynamic Characteristics ◽  
Critical Speed ◽  
Magnetic Bearing ◽  
Rotor System ◽  
Active Magnetic Bearing ◽  
Cracked Rotor ◽  
Harmonic Components ◽  
The Stability ◽  
Amb System ◽  
Cracked Rotor System

The dynamic characteristics of a cracked rotor with an active magnetic bearing (AMB) are theoretically analyzed in this paper. The effects of using optimal controller parameters on the dynamic characteristics of the cracked rotor and the effect of the crack on the stability of the active control system are discussed. It is shown that the dynamic characteristics of the cracked rotor with AMBs are clearly more complex than that of the traditional cracked rotor system. Adaptive control with AMBs may hide the fault characteristics of the cracked rotor, rather than helping to diagnose a crack; this will depend on the controller strategy used. It is very difficult to detect a crack in the AMB-rotor system when the vibration of the rotor system is fully controlled. Only the super-harmonic components of 2X and 3X revolution in the sub-critical speed region can be used as a index to detect a crack in the rotor–AMB system. If the effect of the crack is not considered in designing the controller, then the AMB-rotor system will lose its stability in some cases when cracks appear.

Sign in / Sign up

Export Citation Format

Share Document