CN105866645B - A kind of method and device diagnosing generator discharge failure using noise characteristic frequency range - Google Patents
A kind of method and device diagnosing generator discharge failure using noise characteristic frequency range Download PDFInfo
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- CN105866645B CN105866645B CN201610368469.XA CN201610368469A CN105866645B CN 105866645 B CN105866645 B CN 105866645B CN 201610368469 A CN201610368469 A CN 201610368469A CN 105866645 B CN105866645 B CN 105866645B
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- 238000000034 method Methods 0.000 title claims abstract description 17
- 238000001228 spectrum Methods 0.000 claims abstract description 22
- 238000012360 testing method Methods 0.000 claims abstract description 9
- 230000002159 abnormal effect Effects 0.000 claims description 7
- 238000012545 processing Methods 0.000 claims description 6
- 238000007789 sealing Methods 0.000 claims description 5
- 238000004088 simulation Methods 0.000 claims description 3
- 238000005259 measurement Methods 0.000 claims 16
- 230000000694 effects Effects 0.000 abstract description 2
- 230000005236 sound signal Effects 0.000 description 9
- 230000005540 biological transmission Effects 0.000 description 7
- 238000012544 monitoring process Methods 0.000 description 5
- 238000003745 diagnosis Methods 0.000 description 3
- 238000000605 extraction Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
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- 238000004458 analytical method Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1209—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing using acoustic measurements
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Abstract
The invention discloses a kind of method and devices diagnosing generator discharge failure using noise characteristic frequency range, by arranging multiple noise testing points on generator unit stator top, the characteristic spectra of discharge fault of the preset sound frequency range (1000 6000Hz) as generator in the noise signal of each noise testing point is extracted, and then analyzes and obtains measuring point nearby with the presence or absence of discharge fault.The technical effects of the invention are that generator discharge failure can be fast and accurately diagnosed to be in the case where not influencing generator operation.And this programme is simple and practical, it is easy to operate.Existing noise meter or sound pick-up outfit, small investment can be utilized simultaneously.And it can comprehensively monitor the failure of generating set.
Description
Technical field
The invention belongs to fault diagnosis technical fields, and in particular to a kind of to utilize noise characteristic frequency range diagnosis hair
The method and device of motor discharge fault.
Background technology
The vibration signal of generating set really reflects its running state information, and can not influence equipment in monitoring
Normal operation, by carrying out amplitude, time domain, the analyses such as frequency domain to vibration signal, can real-time judge go out whether generating set is transported
Capable abnormal and corresponding fault type.Vibration signal is few by environmental disturbances, therefore diagnoses steamer hair using vibration monitoring
Motor, hydrogenerator, wind-driven generator failure at home and abroad have been widely used.But there is also one for vibration monitoring
It is a little mainly to monitor low frequency signal using limitation, such as vibrating sensor, but many failures can not be found by low frequency signal；And
Vibrating sensor etc. can not be used by charging in position or locking device.
Invention content
In order to solve the limited, vibrating sensing by existing monitoring fault coverage when vibration signal monitoring generating set at present
The limited technical problem of device installation, the present invention provide it is a kind of using noise characteristic frequency range diagnose generator discharge failure method and
Device.
In order to achieve the above technical purposes, the technical scheme is that,
A method of generator discharge failure being diagnosed using noise characteristic frequency range, is included the following steps,
Step 1：Multiple noise testing points are arranged on generator；
Step 2：Acquire the noise signal of each noise testing point；
Step 3：Extract electric discharge event of the preset sound frequency range in the noise signal of each noise testing point as generator
The characteristic spectra of barrier；
Step 4：Energy summation to the characteristic spectra acquired in step 3；
Step 5：With the energy of characteristic spectra and it is ordinate, to obtain different measuring points using measuring point number as abscissa
Characteristic spectra noise profile curve, and then noise situation of change in distribution curve is obtained, if increased in continuous multiple rules
Or occur abnormal raised measuring point in the one section of measuring point reduced, and the value of the measuring point and the difference of this section of measuring point minimum value are more than threshold
Value, then show that there are discharge faults near the measuring point.
A kind of described method diagnosing generator discharge failure using noise characteristic frequency range, in the step 1, away from
From being uniformly distributed measuring point, each measuring point interval 1m~2m at generator unit stator sealing plate 0.5m.
A kind of described method diagnosing generator discharge failure using noise characteristic frequency range in the step 2, passes through
Microphone or equipment with sound-recording function acquire the noise signal of each measuring point, and frequency range is 100~20kHz.
A kind of described method diagnosing generator discharge failure using noise characteristic frequency range in the step 3, passes through
Hardware simulation filter or Speech processing algorithm, setting high-pass filter are 1000Hz, and low-pass filter frequency is
6000Hz, extract generator noise signal in 1000Hz to 6000Hz as generator discharge fault characteristic spectra.
A kind of described method diagnosing generator discharge failure using noise characteristic frequency range, in the step 4, to hair
The energy summation of 1000Hz to 6000Hz characteristic spectras in each measuring point noise signal of motor；
A kind of described method diagnosing generator discharge failure using noise characteristic frequency range, in the step 5, to survey
Point number is abscissa, with the energy of 1000Hz to 6000Hz characteristic spectras and for ordinate, to obtain different measuring points
1000-6000Hz noise profile curves, and then noise situation of change in distribution curve is obtained, if increased in continuous multiple rules
Or occur abnormal raised measuring point in the one section of measuring point reduced, and the value of the measuring point and the difference of this section of measuring point minimum value are more than threshold
Value 1dB then shows that there are discharge faults near the measuring point.
A kind of device diagnosing generator discharge failure using noise characteristic frequency range, including microphone, audio transmission line, sound
Audio signalprocessing device and display, the microphone are arranged on generator, and the microphone passes through audio transmission line
It is connect with audio signal processor, audio signal processor passes through display after obtained audio signal is extracted characteristic spectra
Device shows result.
A kind of device diagnosing generator discharge failure using noise characteristic frequency range, the microphone is in distance
It is uniformly distributed at generator unit stator sealing plate 0.5m, each microphone interval 1m~2m.
A kind of device diagnosing generator discharge failure using noise characteristic frequency range, the Audio Signal Processing
Device includes filter, signal sampler and digital signal processor, and the filter passes through audio transmission line and microphone
It connects, the signal after filter filtering converts analog signals into digital signal, microprocessor digital signal by signal sampler
Processor by display shows result after being handled the digital signal that signal sampler inputs.
A kind of device diagnosing generator discharge failure using noise characteristic frequency range, the filter include frequency
The low-pass filter that the high-pass filter and frequency that rate is 1000Hz are 6000Hz
The technical effects of the invention are that can be in the case where not influencing generator operation, fast and accurately diagnosis is set out
Motor discharge fault.And this programme is simple and practical, it is easy to operate.Existing noise meter or recording can be utilized to set simultaneously
It is standby, small investment.And it can comprehensively monitor the failure of generating set.
Description of the drawings
Fig. 1 is the flow chart of the present invention；
The structural schematic diagram that Fig. 2 is
Fig. 3 is point layout schematic diagram of the present invention；
Fig. 4 is the noise profile figure of the embodiment of the present invention；
Wherein, 1 it is microphone, 2 be audio transmission line, 3 be filter, 4 be signal sampler, 5 is Digital Signal Processing
Device, 6 be display, 7 be stator, 8 be upper wind-tunnel.
Specific implementation mode
Referring to Fig. 1, Fig. 2, Fig. 3, the present embodiment includes microphone, audio transmission line, audio signal processor and display
Device, microphone are arranged on generator, and microphone is connect by audio transmission line with audio signal processor, at audio signal
Reason device will show result after obtained audio signal extraction characteristic spectra by display.
Wherein microphone is uniformly distributed at generator unit stator sealing plate 0.5m, each microphone interval 1m~2m.
Audio signal processor includes filter, signal sampler and digital signal processor, and filter passes through audio
Transmission line is connect with microphone, and the signal after filter filtering converts analog signals into digital signal by signal sampler,
Microprocessor digital signal processor by display shows result after being handled the digital signal that signal sampler inputs.
The low-pass filter that filter includes the high-pass filter that frequency is 1000Hz and frequency is 6000Hz.
The present invention is uniformly distributed measuring point, each measuring point interval along generator unit stator sealing plate top 0.5m first when implementing
1m~2m.Then the equipment by microphone or with sound-recording function acquires the noise signal of each measuring point, and frequency range includes 100
~20kHz.After obtaining noise signal, by hardware simulation filter or Speech processing algorithm, setting high-pass filter is
1000Hz, low-pass filter frequency 6000Hz, 1000Hz to the 6000Hz extracted in generator noise signal are used as generator
Discharge fault characteristic spectra.Next to 1000Hz to 6000Hz characteristic spectras in each measuring point noise signal of generator
Energy is summed.With the energy of 1000Hz to 6000Hz characteristic spectras and it is ordinate finally using measuring point number as abscissa, to
The 1000-6000Hz noise profile curves of different measuring points are obtained, and then obtain the wave crest in distribution curve and trough situation of change,
If the difference of crest value and valley value is more than 1dB, show that there are discharge faults near corresponding measuring point at the wave crest.
Embodiment：
1, measuring point is laid.In certain hydroelectric power plant, 1# generators are uniformly distributed 16 measuring points along+Y-- X-- Y-- +X directions, survey
Point arrangement is as shown in figure 3, measuring point is located at stator top 0.5m.
2, noise signal records.Using the pulse analyzers of BK companies of Denmark to each measuring point noise record 20 seconds.
3, noise signal extraction and calculating.Using the reflex the poster processing softs extraction generator noise letter of BK companies of Denmark
The characteristic spectra of 1000Hz to 6000Hz in number as the discharge fault of generator, and in each measuring point noise signal
The energy of 1000Hz to 6000Hz characteristic spectras is summed；.
4, electric discharge position judges.Using measuring point number as abscissa, with the energy of 1000Hz to 6000Hz characteristic spectras and it is
Ordinate, to obtain the 1000-6000Hz noise profile curves of different measuring points, as shown in figure 4, obtaining in distribution curve in turn
Noise situation of change, if occur abnormal raised measuring point in one section of measuring point that continuous multiple rules are raised and lowered, and should
The value of measuring point and the difference of this section of measuring point minimum value are more than threshold value 1dB, then show that there are discharge faults near the measuring point.From figure
4 can be seen that, are distributed to measuring point 5 uniformly to rise since measuring point 1, and abnormal raising occurs in measuring point 3, i.e., several with surrounding
Measuring point is compared, and the value of measuring point 3 is obviously not belonging to normal condition, and measuring point 3, compared with minimum point measuring point 1, difference is more than 1dB, therefore
Judge that measuring point 3 has electric discharge.And this section of measuring point of measuring point 6,7,8 is distributed as uniformly declining, situation belongs to normal.Thereafter survey
Point 8-11 is also normal distribution.And in measuring point 12-14, obviously there are unusual fluctuations in measuring point 13, and is more than with the difference of measuring point 14
1dB, therefore there is also electric discharges for measuring point 13.
5, result verification.Find that there are point of discharges and apparent at measuring point 3 and measuring point 13 by local discharge test in overhaul
Spark tracking, demonstrate the correctness of this method.
Claims (5)
1. a kind of method diagnosing generator discharge failure using noise characteristic frequency range, which is characterized in that include the following steps,
Step 1：Multiple noise testing points are arranged on generator；
Step 2：Acquire the noise signal of each noise testing point；
Step 3：Preset sound frequency range in the noise signal of each noise testing point is extracted as the discharge fault of generator
Characteristic spectra；
Step 4：Energy summation to the characteristic spectra acquired in step 3；
Step 5：With the energy of characteristic spectra and it is ordinate using measurement point number as abscissa, to obtain different measurement points
Characteristic spectra noise profile curve, and then noise situation of change in distribution curve is obtained, if increased in continuous multiple rules
Or occur abnormal raised measurement point in the one section of measurement point reduced, and the difference of the value of the measurement point and this section of measurement point minimum value
Value is more than threshold value, then shows that there are discharge faults near the measurement point.
2. a kind of method diagnosing generator discharge failure using noise characteristic frequency range according to claim 1, feature
It is, in the step 1, measurement point, each interval of measuring points 1m is being uniformly distributed at generator unit stator sealing plate 0.5m
~2m.
3. a kind of method diagnosing generator discharge failure using noise characteristic frequency range according to claim 1, feature
It is, in the step 2, the noise signal of each measurement point, frequency is acquired by microphone or the equipment with sound-recording function
Ranging from 100~20kHz.
4. a kind of method diagnosing generator discharge failure using noise characteristic frequency range according to claim 1, feature
It is, in the step 3, by hardware simulation filter or Speech processing algorithm, setting high-pass filter frequency is
1000Hz, low-pass filter frequency 6000Hz, 1000Hz to the 6000Hz extracted in generator noise signal are used as generator
Discharge fault characteristic spectra.
5. a kind of method diagnosing generator discharge failure using noise characteristic frequency range according to claim 1, feature
It is, with the energy of 1000Hz to 6000Hz characteristic spectras and is vertical using measurement point number as abscissa in the step 5
Coordinate to obtain the 1000-6000Hz noise profile curves of different measurement points, and then obtains noise in distribution curve and changes feelings
Condition, if occur abnormal raised measurement point in one section of measurement point that continuous multiple rules are raised and lowered, and the measurement point
The difference of value and this section of measurement point minimum value be more than threshold value 1dB, then show that there are discharge faults near the measurement point.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US11124316B2 (en) * | 2019-03-19 | 2021-09-21 | Wing Aviation Llc | Detecting impending motor failure using audio data |
| CN112067961B (en) * | 2020-10-13 | 2023-08-15 | 哈尔滨工业大学（深圳） | Arc fault detection method, system and storage medium |
| CN112529059B (en) * | 2020-12-04 | 2022-01-14 | 湖南五凌电力科技有限公司 | Unit electromagnetic vibration diagnosis method, system, computer equipment and storage medium |
| CN113790911B (en) * | 2021-08-18 | 2023-05-16 | 中国长江电力股份有限公司 | Abnormal sound detection method based on sound spectrum statistics rule |
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Inventor after: Hu Sheng Inventor after: Peng Jiwen Inventor after: Hao Jianbo Inventor after: Meng Zuohong Inventor after: Xu Bo Inventor after: Zhou Nianguang Inventor after: Wu Xiaowen Inventor after: Tang Jun Inventor after: Sun Bo Inventor after: Chen Xiaoxiang Inventor before: Hu Sheng Inventor before: Hao Jianbo Inventor before: Meng Zuohong Inventor before: Xu Bo Inventor before: Zhou Nianguang Inventor before: Wu Xiaowen |
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Effective date of registration: 20170104 Address after: 100031 Xicheng District West Chang'an Avenue, No. 86, Beijing Applicant after: State Power Networks Co Applicant after: State Grid Hunan Electric Power Company Applicant after: Electric Power Research Institute, State Grid Hunan Electric Power Company Applicant after: Wu Ling Power Corporation bowl slope hydropower plant Address before: 100031 Xicheng District West Chang'an Avenue, No. 86, Beijing Applicant before: State Power Networks Co Applicant before: State Grid Hunan Electric Power Company Applicant before: Electric Power Research Institute, State Grid Hunan Electric Power Company |
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