The criterion on inter-turn short circuit fault diagnose of steam turbine generator rotor windings

This paper analyzes the calculation method of unbalanced electromagnetic force by rotor winding inter-turn short-circuit fault, analytical calculating method neglects saturation, cogging and other factors, so the calculation accuracy is not high, in order to accurately calculate the magnetic field and the unbalanced electromagnetic force, this paper propose to analyze generator magnetic field by a finite element software Ansys, the obtained magnetic field data are further used to analyze the distributed electromagnetic force and the total force that generator rotor suffered, electromagnetic force distribution law of different slots, different levels of inter-turn short-circuit are got, which provide a basis for further studying the full force on generator rotor.

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An Investigation of Excitation Method for Torsional Testing of a Large-Scale Steam Turbine Generator

Journal of Vibration and Acoustics ◽

10.1115/1.1640639 ◽

2004 ◽

Vol 126 (1) ◽

pp. 163-167 ◽

Cited By ~ 1

Author(s):

Yong Chen

Keyword(s):

Steam Turbine ◽

Torsional Vibration ◽

Large Scale ◽

Current Method ◽

Field Testing ◽

Turbine Generator ◽

Higher Modes ◽

Rotor Systems ◽

Generator Rotor ◽

Torsional Testing

Presently, the “negative sequence current method” is widely used in field-testing to determine torsional vibration characteristics of steam turbine generator rotor systems. The natural frequencies of lower modes of vibration can be determined effectively in this way, but higher modes cannot be readily excited. To understand this phenomenon, modal analysis was employed to digitally simulate the dynamic response obtained in torsional vibration testing of a 200MW steam turbine generator rotor system. The calculations were consistent with field experimental results, showing that higher modes are difficult to excite by this method. The research also indicated that higher modes could be excited by certain experimental procedures. The conclusions provide guidelines for future field-testing of large-scale systems.

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Fault Diagnose of Rotor Winding Inter Turn Short Circuit in Generator

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.321-324.1290 ◽

2013 ◽

Vol 321-324 ◽

pp. 1290-1294

Author(s):

Hai Yan Xiao ◽

Xue Wu Wang ◽

Deng Feng Chen

Keyword(s):

Short Circuit ◽

Reference Wave ◽

Magnetic Characteristics ◽

Wave Form ◽

Fault Diagnose ◽

Turbo Generator ◽

Half Wave ◽

Wave Forms ◽

Rotor Winding ◽

Short Circuit Fault

Based on magnetic characteristics of inter turn circuit of rotor windings in turbo generator, and analysis the principles of detecting coil method. Based on the symmetry of generator structure and magnetic character between stator and rotor, three fault diagnose methods are presented in this paper: Wave form limitations, Half-wave sliding superposition and Reference wave forms. The application example shows that Reference wave forms method is capable of diagnosing inter turn fault, its severity, and especially locating the inter turn short circuit fault.

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