Diagnosis of turbine generator typical faults by shaft voltage

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. Some new distorted flux hamonics appear when field windings interturn short circuit happens, the harmonic frequencies change with the generator pole-pair number, and amplitudes increase when the fault get worse. The following experimental work agrees with the theoretical predictions.

[1]  D. R. Albright.  Interturn Short-Circuit Detector for Turbine-Generator Rotor Windings , 1971 .

[2]  Li Xiao.  Measurement and Assessment of Inter-turn Short-circuit Fault in the Rotor of Large Turbogenerator , 2003 .

[3]  Zhu Yu.  Vibration Analysis of Shaft No.10 for Generator No．1 in Pingwei Power Plant , 2000 .

[4]  Nouredine Hadjsaid,et al.  Power system parallel computation by a transputer network , 1999 .

[5]  C. Corenwinder,et al.  Analysis of shaft voltages in large synchronous generators , 1999, IEEE International Electric Machines and Drives Conference. IEMDC'99. Proceedings (Cat. No.99EX272).

[6]  J. F. Lyles,et al.  Vertical hydraulic generators experience with dynamic air gap monitoring , 1992 .

[7]  J. Erdman,et al.  Effect of PWM inverters on AC motor bearing currents and shaft voltages , 1995, Proceedings of 1995 IEEE Applied Power Electronics Conference and Exposition - APEC'95.

[8]  S. Ahmed,et al.  Detection of Rotor Slot and Other Eccentricity-Related Harmonics in a Three-Phase Induction Motor with Different Rotor Cages , 2001, IEEE Power Engineering Review.

[9]  J.-J. Simond,et al.  A novel air-gap monitoring system for large low speed hydro-generators , 2006, 2006 IEEE Power Engineering Society General Meeting.

[10]  P.I. Nippes.  Early warning of developing problems in rotating Machinery as provided by monitoring shaft Voltages and grounding currents , 2004, IEEE Transactions on Energy Conversion.

[11]  J. S. Hsu,et al.  Shaft signals of salient-pole synchronous machines for eccentricity and shorted-field-coil detections , 1994 .

[12]  Wan Shuting,et al.  Analysis of generator vibration characteristic on rotor winding interturn short circuit fault , 2003, Sixth International Conference on Electrical Machines and Systems, 2003. ICEMS 2003..

[13]  C. Corenwinder,et al.  Circulating current analysis in the parallel-connected windings of synchronous generators under abnormal operating conditions , 1999, IEEE International Electric Machines and Drives Conference. IEMDC'99. Proceedings (Cat. No.99EX272).

[14]  S. P. Verma.  Damages due to shaft-potentials in modern generators , 1993, Proceedings. Joint International Power Conference Athens Power Tech,.

[15]  Sun Yi,et al.  The criterion on inter-turn short circuit fault diagnose of steam turbine generator rotor windings , 2007, 2007 International Conference on Electrical Machines and Systems (ICEMS).

[16]  P. I. Nippes.  Magnetism and Stray Currents in Rotating Machinery , 1996 .

[17]  Zhao Hua.  THE NEW CRITERION ON INTER TURN SHORT-CIRCUIT FAULT DIAGNOSE OF STEAM TURBINE GENERATOR ROTOR WINDINGS , 2003 .

[18]  Rajendra Prasad,et al.  Papers in Conference Proceedings , 2014 .

[19]  Wan Shuting,et al.  Fault identification method of rotor inter turn short-circuit using stator winding detection , 2003, Sixth International Conference on Electrical Machines and Systems, 2003. ICEMS 2003..