Results 311 to 320 of about 166,407 (356)

Geometric Effects on Eddy Current Bearing Performance

Journal of Tribology, 1989
The properties of magnetic bearings, particularly those based on repulsive forces due to eddy currents, are determined by a complex mixture of electrical and mechanical length and time scales. A perturbation solution for the magnetic field structure based on careful ordering of these parameters has permitted the effects of realistic gap geometries to ...
J. A. Tichy, K. A. Connor
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Inverter driven induction motor bearing current solutions

Record of Conference Papers. Industry Applications Society. Forty-Ninth Annual Conference. 2002 Petroleum and Chemical Industry Technical Conference, 2003
Bearing currents in induction motors can result in premature bearing failure. In this paper, the sources of sine wave and inverter driven motor bearing currents and the potential current paths are identified. These current paths are shown to flow through what are commonly considered to be electrical insulators.
R.F. Schiferl, M.J. Melfi, J.S. Wang
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Current limits of PTFE in sliding bearings

IABSE Reports, 2010
<p>The European standard EN 1337 on bridge bearings is supported by experimental studies dating to the ‘70s and the ‘80s, which are not suitable to account for recent issues relevant to operations of steel–PTFE bridge bearings under extreme conditions, like high environment temperatures or high velocities of sliding.
QUAGLINI, VIRGINIO, C. TAVECCHIO, DUBINI, PAOLO, CUMINETTI, DANIELE, FERRONI, DANIELA   +4 more
openaire   +2 more sources

Characteristics of Shaft Voltage and Bearing Currents

IEEE Industry Applications Magazine, 1997
This article reviews investigations into reduced bearing life due to voltage source adjustable speed drive (ASD) AC motor operation. Relevant bearing failure mechanisms and indicators are discussed. dv/dt and electric discharge machining (EDM) contributions are discussed and experimental data presented showing the voltage levels on motor shafts when ...
Dave Busse, Jay Erdman, Russ Kerkman, Dave Schlegal, Gary Skibinski   +4 more
openaire   +1 more source

Current Practice in Journal Bearings

1969
It is advantageous from the production point of view for a manufacturer to use one standard design of journal bearing, made in a small number of standard sizes. The degree of standardization attained is, however, limited by other considerations. The economic benefits of reduction of machine dimensions and of reduction of bearing loss justify the use of
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Bearing currents in doubly-fed induction generators

2005 European Conference on Power Electronics and Applications, 2005
An increasing demand on the quality of wind power systems affects also more and more the fields of lifetime and reliability. But, problems like bearing damages because of bearing currents counteract these desired demands. Especially doubly fed induction generators, which are wide spread in use for wind turbines up to the MW-class can be limited in ...
J. Zitzelsberger, W. Hofmann, A. Wiese, P. Stupin   +3 more
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Eddy current losses in passive magnetic bearings

Journal of Applied Physics, 2002
Passive magnetic bearings built with permanent magnets, such as NdFeB (neodynium–iron–boron) or SmCo (samarium–cobalt), are very reliable systems when used for industrial applications such as centrifuges or flywheels, as they do not require any electromagnetic coil supply. Nevertheless, during the rotational motion, gyroscopic effects (like precession)
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Ocean Currents, Jet Streams, and Polar Bears

2021
Abstract This chapter is divided into four sections, describing various impacts of glacier melt on different Earth ecosystems, including the effects of melting ice and water temperature on changes to ocean currents, on the global air Jet Stream, and on land surfaces, such as the popping up effect (the surface rebound effect) of the Earth
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Analysis of an Eddy Current Journal Bearing

Journal of Tribology, 1988
Nearly all magnetic bearings which have found use in modern technology are based on the attractive force between a magnet and a magnetic material. A distinct disadvantage is that such devices are inherently unstable and require active feedback for operation.
K. A. Connor, J. A. Tichy
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Research of bearing voltage and bearing current in induction motor drive system

2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC), 2016
To solve bearing electric corrosion of motor drive system, the mechanism of bearing voltage and bearing current is studied. To validate the mechanism, the motor driven by high frequency PWM pulse system is established. The model of drive system based on MATLAB/SIMULINK is introduced.
Zhuxia Fan, Yongjian Zhi, Bingquan Zhu, Guanglin Yan, Yu Shi   +4 more
openaire   +1 more source