Results 211 to 220 of about 10,109 (244)

Analysis of shaft voltages in large synchronous generators

IEEE International Electric Machines and Drives Conference. IEMDC'99. Proceedings (Cat. No.99EX272), 2003
In order to improve maintenance of large turbogenerators, a new diagnostic tool is developed by analysing shaft voltages. This study is validated by a comparison between the measurements made on a 30 kVA synchronous machine and its modelling with a finite element program.
J.-E. Torlay, C. Corenwinder, A. Audoli, J. Herigault, A. Foggia   +4 more
openaire   +1 more source

Shaft voltages and rotating machinery

Industry Applications Society 38th Annual Petroleum and Chemical Industry Conference, 1993
In order to determine whether a machine is experiencing shaft voltage and current problems, recognition of the four types of damage is imperative. The four distinct types of shaft current damage, frosting, spark tracks, pitting, and welding are described. The four shaft voltage sources and their means of generation are discussed in detail.
openaire   +1 more source

A Survey on Shaft Voltage of Large Generator

Applied Mechanics and Materials, 2013
Shaft voltage is widely existed in the operation of generator and needed to pay more attentions. Based on the mechanism of generator shaft voltage, this paper analyses and expounds the harmfulness of shaft voltage and shaft current, then summarizes the prevention and control measures of shaft voltage and the research status.
Ling Chen, Hong Hua Wang, Cheng Liang Wang, Chao Tan   +3 more
openaire   +1 more source

Electrostatic Shaft Voltage on Steam-Turbine Rotors

Journal of Engineering for Power, 1959
Several different types of shaft voltages can be present on steam-turbine rotors. The one type that has gained increased significance in the past five years is the direct-current or electrostatic voltage. Prior to this period, electrostatic shaft voltage had not been a problem.
J. M. Gruber, E. F. Hansen
openaire   +1 more source

A complete excitation-shaft-bearing model to overcome the shaft induced voltage and bearing current

2011 2nd Power Electronics, Drive Systems and Technologies Conference, 2011
This paper proposes a complete distributed model for investigating the induced shaft voltage and bearing current in turbo generators due to the interaction with the static excitation systems. This undesirable voltage affects the insulations gradually, lowering the life expectancy of the whole system.
Reza Kazemi Golkhandan, Mohammad Tavakoli Bina, Masoud Aliakbar Golkar, Mohsen Jokar   +3 more
openaire   +1 more source

Study of shaft voltage of a simplified synchronous generator

International Journal of Applied Electromagnetics and Mechanics, 2019
Shaft voltage is a well-known variable in the case of large turbo-generators for its potential destructive effect. However, as it is due to magnetic asymmetries, its use as a diagnosis indicator can be very interesting. Previous works were carried out to investigate the harmonic contents of this voltage in the case of some usual defects such as ...
Darques, Kévin, Tounzi, Abdelmounaïm, Le Menach, Yvonnick, Beddek, Karim   +3 more
openaire   +1 more source

Diagnosis of turbine generator typical faults by shaft voltage

2012 IEEE Industry Applications Society Annual Meeting, 2012
Relationships between shaft voltages and static eccentricities are studied, theoretical analysis shows that shaft voltages are induced by the ‘distorted fluxes’ caused by static eccentricities, shaft voltages mainly contain odd harmonics, the harmonic amplitudes increase under greater eccentricities.
Wu Yucai, Li Yonggang, Li Heming
openaire   +1 more source

Reduction of Inverter-Induced Shaft Voltages Using Electrostatic Shielding

2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA), 2019
The simple three-phase inverter topology that is most widely used in electrical machine drive systems produces a large, high-frequency common-mode voltage. Through capacitive coupling, a fraction of this common-mode voltage typically appears on the machine’s shaft relative to ground.
Stiaan Gerber, Rong-Jie Wangi
openaire   +1 more source

Shaft current and voltage protection relay

2014
The paper deals with the specific protection relay for all types of generators. The instrument, called Shaft Current and Voltage Protection Relay (SCVP) was developed at KONCAR – Electric Engineering Institute Inc. This instrument is a part of Institute's product line used for monitoring and diagnosis of rotating electrical machines. The most important
Elez, Ante, Polak, Josip
openaire   +2 more sources

Converter Caused Shaft Voltages

2013
Parasitic effects caused by static frequency converters, like electromagnetic interference (EMI), may endanger the reliable operation of electrical machines up to 500 MVA. They can cause shaft voltages up to 300 Vpp, if a non optimized converter design is chosen. Shaft voltages occur in converter fed drives due to different effects [7.1-7.9].
openaire   +1 more source