scholarly journals A Transfer Function Approach to Active Magnetic Bearing Control Systems.

1999 ◽  
Vol 65 (637) ◽  
pp. 3507-3514 ◽  
Author(s):  
Takeshi MIZUNO
Keyword(s):  
Transfer Function ◽  
Control Systems ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Function Approach

Evaluation of Q-Values of a Rotor-Bearing System Using a Modal Open Loop Transfer Function

2009 ◽  
Author(s):  
Hiroyuki Fujiwara ◽  
Yasuo Fukushima ◽  
Naohiko Takahashi ◽  
Hiroto Oyama ◽  
Osami Matsushita
Keyword(s):  
Transfer Function ◽  
Damping Ratio ◽  
Magnetic Bearing ◽  
Open Loop ◽  
Active Magnetic Bearing ◽  
Q Value ◽  
Oil Whip ◽  
Displacement Sensors ◽  
Loop Transfer Function ◽  
Value Estimation

As indicated by ISO standard 10816, Q-value estimation is very important for rotating machinery commission and/or machine safety operation. Impulse tests and resonance curve measurements are commonly contributed to Q-value estimation. Instead of two methods, we are developing a new method using open-loop transfer function (Go) at real operational condition. In this paper, we present a theoretical background on how to measure the open loop transfer function. Our key technique is the measurement of the modal coordinates with a combination of several displacement sensors. Concerning the experimental measurement of Go, we use multiple sensors and only one active magnetic bearing (AMB) in a rotor system supported by oil-film/ball bearing. This Go is converted to damping ratio. In fact, a smaller damping ratio is recognized just before oil-whip instability by our open loop measurement. In addition, we set a dynamic damper which has been developed for suppression of oil whip instability, and an increasing damping ratio is also recognized by our method.

scholarly journals 449 Building of control systems for High Load Active Magnetic Bearing used in a heating roll

2009 ◽  
Vol 2009 (0) ◽  
pp. _449-1_-_449-6_
Author(s):  
Daiki KISHIMOTO ◽  
Satoshi UENO ◽  
Jun YAMAMOTO ◽  
Motomasa HIRAO ◽  
Osamichi MATSUKAWA ◽  
...  
Keyword(s):  
Control Systems ◽  
Magnetic Bearing ◽  
High Load ◽  
Active Magnetic Bearing

Stability constraints of active magnetic bearing control systems

2007 ◽  
Vol 80 (12) ◽  
pp. 1893-1902 ◽  
Author(s):  
Nan-Chyuan Tsai ◽  
Bo-Yang Wu ◽  
Sheng-Liang Hsu
Keyword(s):  
Control Systems ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing

Finite Element Analysis and Experimental Validation of Transfer Function of Rotating Shaft System With Both an Open Crack and Anisotropic Support Stiffness

2018 ◽  
Vol 141 (2) ◽  
Author(s):  
Qiang Yao ◽  
Tsuyoshi Inoue ◽  
Shota Yabui
Keyword(s):  
Finite Element ◽  
Transfer Function ◽  
Transfer Functions ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Open Crack ◽  
Rotating Shaft ◽  
Element Analysis ◽  
Shaft System ◽  
Stiffness Anisotropy

In this paper, transfer function of rotating shaft system for detecting transverse open crack is developed. Rotating shaft system is modeled using one-dimensional finite element method (1D-FEM), and quantitative analysis is performed. Open crack is modeled as weak asymmetry rotating with shaft's rotation. It is known that, when both open crack and support stiffness anisotropy coexist, various frequency components of shaft's vibration are generated through their successive interaction. This paper evaluates the order of these components, and concludes that first five main components are enough to investigate interaction of open crack and support stiffness anisotropy. Then, five sets of transfer functions for these components are derived. The validity of this set of transfer functions is confirmed by numerical simulation. Moreover, excitation experiment utilizing active magnetic bearing (AMB) is performed, and the validity of derived transfer function was verified experimentally.

Sign in / Sign up

Export Citation Format

Share Document