Apparatus and method for detecting vibrations of the shaft assembly in an electrical machine
IPC분류정보
국가/구분
United States(US) Patent
등록
국제특허분류(IPC7판)
G01H-011/06
G01H-011/00
출원번호
US-0075521
(2005-03-09)
우선권정보
CH-1529/02(2002-09-10)
발명자
/ 주소
Hobelsberger,Max
Kirchhoff,Ingo
Posedel,Zlatimir
출원인 / 주소
Alstom Technology Ltd.
대리인 / 주소
Darby &
인용정보
피인용 횟수 :
8인용 특허 :
12
초록▼
A method for detecting vibrations of a shaft of an electrical machine includes measuring at least one of a shaft voltage and a shaft current and analyzing the measured at least one of the shaft voltage and the shaft current so as to determine the vibrations. In addition, an apparatus for detecting v
A method for detecting vibrations of a shaft of an electrical machine includes measuring at least one of a shaft voltage and a shaft current and analyzing the measured at least one of the shaft voltage and the shaft current so as to determine the vibrations. In addition, an apparatus for detecting vibrations of a shaft of an electrical machine includes a first grounding device disposed at a first point on the shaft on a first side of the electrical machine and a second grounding device disposed at a second point of the shaft on a second side of the electrical machine. The second grounding device is configured to measure at least one of a shaft voltage and a shaft current.
대표청구항▼
What is claimed is: 1. A method for detecting vibrations of a shaft of an electrical machine, the method comprising: measuring at least one of a shaft voltage and a shaft current so as to provide a signal; and analyzing the signal so as to determine a presence and a type of vibrations of the shaft,
What is claimed is: 1. A method for detecting vibrations of a shaft of an electrical machine, the method comprising: measuring at least one of a shaft voltage and a shaft current so as to provide a signal; and analyzing the signal so as to determine a presence and a type of vibrations of the shaft, the type being at least one of torsional vibrations, bending vibrations, and oscillations. 2. The method as recited in claim 1, wherein the electrical machine includes a generator and the measuring includes providing a connection to ground at a first point on the shaft upstream of the generator and tapping off the at least one of the shaft voltage and the shaft current at a second point on the shaft downstream of the generator, and wherein the analyzing is performed in an analysis unit. 3. The method as recited in claim 2, wherein the tapping off is performed using a high-resistance RC module. 4. The method as recited in claim 1, wherein the measuring is performed as a function of time. 5. The method as recited in claim 4, wherein the electrical machine operates at a system frequency and includes a number of pole pairs, and wherein the measuring includes sampling at a sampling rate corresponding to the system frequency or to integral multiples of the system frequency divided by the number of pole pairs. 6. The method as recited in claim 5, wherein the analyzing includes investigating a signal corresponding to the measured shaft voltage or current and having a baseband, the investigating being performed with regard to at least one of a frequency modulation, an amplitude modulation, and frequency lines in the baseband. 7. The method as recited in claim 6, wherein in the analyzing includes evaluating transient processes in a spectrum. 8. The method as recited in claim 7, wherein the evaluating of the transient is performed so as to detect natural frequencies of the shaft assembly. 9. The method as recited in claim 6, wherein the analyzing includes subjecting a section of the signal to a Fourier transformation at a carrier frequency, dividing integral harmonics thereof by the number of pole pairs, and analyzing a resulting spectrum for at least one of instances of line broadening, sidebands, and frequency lines in the baseband. 10. The method as recited in claim 9, wherein the subjecting the section of the signal to the Fourier transformation is performed after a demodulation or down-mixing of the signal. 11. The method as recited in claim 9, wherein the carrier frequency is the system frequency. 12. The method as recited in claim 6, wherein the measuring includes sampling the signal at a sampling rate of 1-10 kHz, and wherein the analyzing includes subjecting sections of the signal in the range from 10 k to 100 k data points to a Fourier transformation so as to determine fine structures in the signals as occur in oscillations and/or torsional vibrations. 13. The method as recited in claim 12, wherein transient shifts or instances of broadening of the lines at the system frequency or at harmonic multiples thereof divided by the number of pole pairs are considered to be an indication of oscillations. 14. The method as recited in claim 12, wherein transient phase modulations are considered to be an indication of torsional vibrations. 15. The method as recited in claim 6, wherein the measuring includes sampling the signal at a sampling rate of 1-10 kHz, and wherein the analyzing includes subjecting sections of the signal in the range from 0.5 k to 1.5 k data points to a Fourier transformation so as to determine bending vibrations. 16. The method as recited in claim 15, wherein transient, non-harmonic lines at frequencies in the range from 1 to 300 Hz are considered to be an indication of bending vibrations in the spectrum. 17. The method as recited in claim 1, wherein the type of vibrations include natural vibration frequencies. 18. The method as recited in claim 17, wherein the natural frequencies include at least one of: a) horizontal and/or vertical, bending-critical natural frequencies; b) natural torsion frequencies; and c) natural oscillation frequencies. 19. The method as recited in claim 18, further comprising determining the amplitude and phase at the natural frequencies. 20. The method as recited in claim 17, further comprising categorizing the natural vibration frequencies as critical if the natural vibration frequencies or their harmonic multiples are in the region of +/-10% of the rated speed. 21. The method as recited in claim 1, wherein the analyzing of the signal includes determining at least one of a temporal sequence of the vibrations and an intensity of the vibrations in addition to determining the type of vibrations. 22. An apparatus for detecting vibrations of a shaft of an electrical machine, comprising: a first grounding device disposed at a first point on the shaft on a first side of the electrical machine; a second grounding device disposed at a second point of the shaft on a second side of the electrical machine, wherein the second grounding device is configured to measure at least one of a shaft voltage and a shaft current and provide a measurement signal; and an analysis unit in operative connection with the second grounding device configured to receive the measurement signal and to determine a presence and a type of vibrations of the shaft, the type being one of torsional vibrations, bending vibrations, and oscillations of the shaft. 23. The apparatus as recited in claim 22, further comprising at least one metal stranded wire disposed on at least one of the first and second grounding devices so as to make contact with the shaft. 24. The apparatus as recited in claim 22, wherein the first grounding device has a first contact apparatus for contacting the shaft, a low-value resistor connected to the contact apparatus, a high-value resistor connected to ground, and a fuse being disposed in parallel with the high-value resistor. 25. The apparatus as recited in claim 22, wherein the second grounding device has a second contact apparatus for contacting the shaft, a fuse connected to the contact apparatus, one or more parallel-connected capacitors, a resistor connected to ground in parallel with the one or more capacitors, and a shunt resistor disposed between ground and one of the one or more capacitor and the resistor, and wherein the shaft voltage is tapped off between the fuse and the ground connection, and the shaft current is tapped off via the shunt resistor. 26. The apparatus as recited in claim 25, wherein the signal corresponds to at least one of the measured shaft voltage and the measured shaft current determined as a function of time, the analysis unit including a first element for digitizing the signal and subjecting the digitized signal to a Fourier transformation so as to produce transformed data, and a second element configured to spectrally displaying the transformed data. 27. The apparatus as recited in claim 26, wherein the presence, type and intensity of vibrations of the shaft are determined automatically numerically in accordance with specific criteria and displayed in simplified form. 28. The apparatus as recited in claim 22, wherein the analysis unit is configured to determine at least one of a temporal sequence and an intensity of the vibrations in addition to determining the type of vibrations.
연구과제 타임라인
LOADING...
LOADING...
LOADING...
LOADING...
LOADING...
이 특허에 인용된 특허 (12)
Wolfinger John F. (Schenectady NY), Apparatus and method for measuring torsional vibration.
Koziel Reinhold (Mlheim DEX) Fork Kurt (Neunkirchen DEX) Weidner Jrgen (Essen DEX), Method for partial discharge detection and breaking spark measuring in dynamo-electric high-voltage machines, and an app.
Hobelsberger, Max; Kirchhofff, Ingo; Kohler, Rene; Posedel, Zlatimir, Protective and monitoring apparatus for a generator, and use of such a protective and monitoring apparatus.
Gerez, Valerio; Griffaton, Julien Christian Pascal; Jadczak, Edouard Joseph, Method and device for monitoring torsional vibrations of a rotary shaft of a turbine engine.
Helle, Lars; Lindholm, Morten; Ottesen, Jari; Nieuwenhuizen, John Johannes Mathias Hubertus, Protection system for an electric generator, wind turbine and use hereof.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.