Abnormality diagnostic device for rolling bearing, wind turbine generation apparatus and abnormality diagnostic system

Patent metadata

Field	Value
Publication number	US-9423290-B2
Application number	US-201013520418-A
Country	US
Kind code	B2
Filing date	Dec 24, 2010
Priority date	Jan 4, 2010
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

An effective value operation unit calculates an effective value of a vibration waveform of a bearing, the vibration waveform being measured by using a vibration sensor. An envelope processing unit performs envelope processing on the vibration waveform measured by using the vibration sensor, thereby generating an envelope waveform of the vibration waveform. An effective value operation unit calculates an effective value of an AC component of the envelope waveform generated by the envelope processing unit. A diagnostic unit diagnoses an abnormality of the bearing based on the effective value of the vibration waveform calculated by the effective value operation unit and the effective value of the AC component of the envelope waveform calculated by the effective value operation unit.

First claim

The invention claimed is:

1. An abnormality diagnostic device for a rolling bearing, comprising:
a vibration sensor for measuring a vibration waveform of the rolling bearing; and
a processing unit for diagnosing an abnormality of said rolling bearing,
said processing unit including:
a first operation unit calculating an effective value of said vibration waveform measured by using said vibration sensor,
an envelope processing unit generating an envelope waveform of said vibration waveform by performing envelope processing on said vibration waveform measured by using said vibration sensor,
a filter extracting an AC component of said envelope waveform generated by said envelope processing unit,
a second operation unit calculating an effective value of the AC component of said envelope waveform extracted by said filter, and
a diagnostic unit diagnosing the abnormality of said rolling bearing based on transition of time changes in the effective value of said vibration waveform calculated by said first operation unit and the effective value of the AC component of said envelope waveform calculated by said second operation unit.

2. The abnormality diagnostic device for a rolling bearing according to claim 1 , further comprising a rotation sensor for detecting a rotational speed of one of a shaft supported by said rolling bearing and said rolling bearing, wherein
said processing unit further includes
a modified vibration degree calculation unit calculating a modified vibration degree obtained by normalizing, by said rotational speed, the effective value of said vibration waveform calculated by said first operation unit, and
a modified modulation degree calculation unit calculating a modified modulation degree obtained by normalizing, by said rotational speed, the effective value of the AC component of said envelope waveform calculated by said second operation unit, and

said diagnostic unit diagnoses the abnormality of said rolling bearing based on said modified vibration degree and said modified modulation degree.

3. The abnormality diagnostic device for a rolling bearing according to claim 2 , wherein said diagnostic unit diagnoses the abnormality of said rolling bearing based on transition of time changes in said modified vibration degree and said modified modulation degree.

4. The abnormality diagnostic device for a rolling bearing according to claim 1 , wherein
said processing unit further includes a frequency analysis unit performing a frequency analysis on at least one of said vibration waveform and said envelope waveform, and
said diagnostic unit further presumes an abnormal portion of said rolling bearing based on the result of analysis obtained by said frequency analysis unit.

5. The abnormality diagnostic device for a rolling bearing according to claim 1 , wherein said vibration sensor includes an acceleration sensor.

6. The abnormality diagnostic device for a rolling bearing according to claim 1 , further comprising a displacement sensor for detecting a relative displacement between an inner ring and an outer ring of said rolling bearing, wherein
said diagnostic unit diagnoses the abnormality of said rolling bearing by further using a detected value of said displacement sensor.

7. The abnormality diagnostic device for a rolling bearing according to claim 1 , further comprising a temperature sensor for measuring the temperature of said rolling bearing, wherein
said diagnostic unit diagnoses the abnormality of said rolling bearing by further using a measured value of said temperature sensor.

8. The abnormality diagnostic device for a rolling bearing according to claim 1 , further comprising a sensor for measuring the amount of impurities contained in a lubricant of said rolling bearing, wherein
said diagnostic unit diagnoses the abnormality of said rolling bearing by further using a measured value of said sensor.

9. The abnormality diagnostic device for a rolling bearing according to claim 1 , further comprising a rotation sensor for detecting a rotational speed of one of a shaft supported by said rolling bearing and said rolling bearing, wherein
said envelope processing unit includes
an absolute value detection unit outputting an absolute value of said vibration waveform, and
an envelope detection unit generating said envelope waveform by performing attenuation processing with a predetermined time constant on an output signal from said absolute value detection unit, and

said time constant is set based on said rotational speed.

10. The abnormality diagnostic device for a rolling bearing according to claim 9 , wherein said time constant is set to be less than or equal to a half cycle of rotation of a rolling element in said rolling bearing.

11. The abnormality diagnostic device for a rolling bearing according to claim 10 , wherein said time constant is set to be more than or equal to 0.5 times said half cycle.

12. The abnormality diagnostic device for a rolling bearing according to claim 9 , wherein said time constant is set to be less than or equal to a passing cycle of a rolling element relative to a stationary ring of said rolling bearing.

13. The abnormality diagnostic device for a rolling bearing according to claim 12 , wherein said time constant is set to be more than or equal to 0.5 times said passing cycle.

14. The abnormality diagnostic device for a rolling bearing according to claim 1 , wherein the filter is a high pass filter (HPF) that removes a DC component of said generated envelope waveform, and the second operation unit calculates the effective value of the AC component of said envelope waveform having the DC component removed.

15. A wind turbine generation apparatus comprising:
a blade receiving wind force;
a main shaft connected to said blade;
a generator connected to one of said main shaft and a gearbox for accelerating rotation of said main shaft;
a plurality of rolling bearings provided in said main shaft, said gearbox and said generator; and
an abnormality diagnostic device diagnosing an abnormality of at least one of said plurality of rolling bearings,
said abnormality diagnostic device including
a vibration sensor for measuring a vibration waveform of a rolling bearing to be diagnosed, and
a processing unit for diagnosing an abnormality of the rolling bearing to be diagnosed,

said processing unit including
a first operation unit calculating an effective value of said vibration waveform measured by using said vibration sensor,
an envelope processing unit generating an envelope waveform of said vibration waveform by performing envelope processing on said vibration waveform measured by using said vibration sensor,
a filter extracting an AC component of said envelope waveform generated by said envelope processing unit,
a second operation unit calculating an effective value of the AC component of said envelope waveform extracted by said filter, and
a diagnostic unit diagnosing the abnormality of said rolling bearing based on transition of time changes in the effective value of said vibration waveform calculated by said first operation unit and the effective value of the AC component of said envelope waveform calculated by said second operation unit.

16. The wind turbine generation apparatus according to claim 15 , wherein the filter is a high pass filter (HPF) that removes a DC component of said generated envelope waveform, and the second operation unit calculates the effective value of the AC component of said envelope waveform having the DC component removed.

17. An abnormality diagnostic system comprising

Assignees

• Sakaguchi Tomoya
• Ninoyu Nobuyuki
• Hirata Junichi
• Sakakibara Yasuhiko
• Ntn Toyo Bearing Co Ltd

Inventors

• Sakaguchi Tomoya
• Ninoyu Nobuyuki
• Hirata Junichi
• Sakakibara Yasuhiko

Classifications

• G01M13/045

  Acoustic or vibration analysis · CPC title

• F03D80/70

  Bearing or lubricating arrangements · CPC title

• G01H1/003 Primary

  of rotating machines (G01H1/10 takes precedence) · CPC title

• F05B2270/334

  Vibration measurements · CPC title

• F03D17/00

  Monitoring or testing of wind motors, e.g. diagnostics (testing during commissioning of wind motors F03D13/30) · CPC title