Theoretical research on short circuit fault of rotor inner winding in large turbo generator

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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Transient Electromagnetic Torque Calculation Method for Short Circuit Fault of Turbo Generator Set

Proceedings of the 2015 International Symposium on Energy Science and Chemical Engineering ◽

10.2991/isesce-15.2015.66 ◽

2015 ◽

Author(s):

Haihua Zhang ◽

Shiwu Xiao ◽

Xiaoqing Xiao ◽

Likun Zheng

Keyword(s):

Calculation Method ◽

Short Circuit ◽

Electromagnetic Torque ◽

Transient Electromagnetic ◽

Turbo Generator ◽

Short Circuit Fault

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Study on Dynamic Response of Torsional Vibration of Turbo-Generator Unit Caused by Short Circuit Fault

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.566.248 ◽

2012 ◽

Vol 566 ◽

pp. 248-252 ◽

Cited By ~ 1

Author(s):

Cheng Bing He ◽

Dong Chao Chen ◽

Yu Jiong Gu

Keyword(s):

Torsional Vibration ◽

Short Circuit ◽

Dynamic Responses ◽

Stable Operation ◽

Two Phase ◽

Time Frequency ◽

Turbo Generator ◽

Complex Morlet Wavelet ◽

Generator Terminal ◽

Short Circuit Fault

When short circuit faults happen near power plant or generator terminal, severe transient torque shock will act on the shaft system, which seriously affects the safe and stable operation of the unit. Using the increment transfer matrix method, the dynamic responses of torsional vibrations are calculated in this work. Combined with the complex Morlet wavelet and time-frequency contour map, the time-frequency domain characters of dynamic torque are analyzed. The analyzed results show that the torque value caused by three phase short circuit fault is largest. The order of torque value from high to low is two phase short circuit to ground, two phase interphase short circuit and single phase short circuit. The electric distance between short circuit point and generator is more short, and the torsional vibration is more serious.

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Analysis on Torsional Stresses in Turbo-Generator Shafts due to Two-Phase Short-Circuit Fault

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.397-400.427 ◽

2013 ◽

Vol 397-400 ◽

pp. 427-430 ◽

Cited By ~ 1

Author(s):

Yu Jiong Gu ◽

Jing Xu

Keyword(s):

Cross Sections ◽

Safety Management ◽

Short Circuit ◽

Target System ◽

Fe Method ◽

Two Phase ◽

Management Level ◽

Turbo Generator ◽

Frequency Components ◽

Short Circuit Fault

Taking a 660MW turbine generator shaft system as a target system, the torsional stresses responses are calculated under two-phase short-circuit fault by the finite element (FE) method which can obtain torsional stresses in local areas accurately. The results show that torsional stresses threaten the safety of shafts appear at the first several cycles of the vibration. And the amplitude of stress in weak cross sections located between the low pressure cylinder and the generator is much greater. In addition, the proportion of torsional stresses frequency components in different sections is distinct. The results are helpful to improve the safety management level of the unit.

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