Fault Diagnosis Based on ANN for Turn-to-Turn Short Circuit of Synchronous Generator Rotor Windings

H. Z. MA, L. PU

.

DOI: 10.4236/jemaa.2009.13028                

Abstract

Rotor winding turn-to-turn short circuit is a common electrical fault in steam turbines. When turn-to-turn short circuit fault happens to rotor winding of the generator, the generator terminal parameters will change. According to these parameters, the conditions of the rotor winding can be reflected. However, it is hard to express the relations between fault information and generator terminal parameters in accurate mathematical formula. The satisfactory results in fault diagnosis can be obtained by the application of neural network. In general, the information about the severity level of the generator faults can be acquired directly when the faulty samples are found in the training samples of neural network. However, the faulty samples are difficult to acquire in practice. In this paper, the relations among active power, reactive power and excitation current are discovered by analyzing the generator mmf with terminal voltage constant. Depending on these relations, a novel diagnosis method of generator rotor winding turn-to-turn short circuit fault is proposed by using ANN method to obtain the fault samples directly, without destructive tests.

Keywords

Generator, Rotor Winding, Turn-to-turn Short Circuit, ANN, Diagnosis

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	W. J. Wang and L. Gui, “Present situation and improvement of relay protection for large sized generator transformer set of 600~1000MW,” Huadian Technology, Vol. 30, No. 1, pp. 5–8, 2008.
[2]	W. Q. Li, “Prevention and fault diagnosis of turbogenerator,” Beijing: Chinese electric power publisher, 2002.
[3]	S. Wan, H. M. LI and Y. G. LI, “Analysis of generator vibration characteristic on rotor winding inter-turn short circuit fault,” Proceedings of the CSEE, Vol. 25, No. 10, pp. 122–126, 2005.
[4]	H. W. Fang, C. L. Xia and J. Xiu, “Analysis of generator electro-magnetic torque on armature winding inter-turn short circuit fault,” Proceedings of the CSEE, Vol. 27, No. 15, pp. 83–87, 2007.
[5]	G. G. Mao, “Reasons of failures occurred in large capacity turbogenerators in China,” Power System Technology, Vol. 24, No. 11, pp. 1–7, 2000.
[6]	R. J. Streifel, R. J. Marks II, and M. A. EI-Sharkawi, “Detection of shorted-turns in the field winding of turbine -generator rotors using novelty detectors development and field test,” IEEE Trans on Energy Conversion, Vol. 11, No. 2, pp. 312–317, 1996.
[7]	A. S. Kulkarni, M. A. El-Sharkawi, R. J. Marks II, G. Andexler, X. Jian, and I. Kerszenbaum, “Development of a technique for on-line detection of shorts in field windings of turbine-generator rotors: Circuit design and testing,” IEEE Trans on Energy Conversion, Vol. 15, No. 1, pp. 8–13, 2000.
[8]	S. E. Guttormsson, R. J. Marks II, and M. A. EI-Sharkawi, “Elliptical novelty grouping for on-line short-turn detection of excited running rotors,” IEEE Transactions on Energy Conversion, Vol. 14, No. 1, pp. 16–22, 1999.
[9]	D. W. Auckl, I. E. D. Pickup, and R. Shuttleworth, “Novel approach to alternator field winding inter-turn fault detection,” IEE Proc., Gener., Transm., Distrib., Vol. 142, No. 2, pp. 97–102, 1995.