CN1204410C - Ultrasonic reflection detecting device and mehtod for diagnosis of insulation state of stator for large electric generator - Google Patents
Ultrasonic reflection detecting device and mehtod for diagnosis of insulation state of stator for large electric generator Download PDFInfo
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- CN1204410C CN1204410C CN 02139424 CN02139424A CN1204410C CN 1204410 C CN1204410 C CN 1204410C CN 02139424 CN02139424 CN 02139424 CN 02139424 A CN02139424 A CN 02139424A CN 1204410 C CN1204410 C CN 1204410C
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Abstract
The present invention discloses an ultrasonic reflection detecting device and a method thereof for the diagnosis of the insulation state of stators for a large electric generator, which is used for measuring ultrasonics characteristic parameters of the stator insulation for the large electric generator. The insulation aging state is diagnosed by detecting insulation internal defects. The detecting device of the present invention comprises couplant agents, an ultrasonic straight beam probe, an ultrasonic wave generating and receiving device, a data collecting card and a notebook computer, and all component parts are mutually connected through coaxial cables or data transmission lines. The present invention can measure the ultrasonics characteristic parameter of the stator insulation of motors (300MW, 18kv)which are used within 23 years under background noise of a generator site 90dB(A), and measured minimum size of the insulation defects is 0.9mm. The volume of the main body part of the present invention relates to 150mm*150mm*100mm, the weigh is 2.5kg, and the aims of small type and portability are achieved. The device has the advantages of strong interference proofing performance, high accuracy, fast data processing, portability, etc., and is particularly for the on-site detection of the aging condition of the stator insulation of the large electric generator.
Description
One, technical field
The invention belongs to technical field of motors, relate to motor stator insulated ageing state diagnostic techniques, particularly a kind of ultrasonic reflection pick-up unit and method thereof of high-rating generator stator insulation condition diagnosing.
Two, background technology
By retrieval, up to the present, also do not adopt the ultrasonic reflection method to carry out the bibliographical information that the high-rating generator stator insulation detects in the world, what also yet there are no other carries out the bibliographical information of on-site diagnosis hardware system of high-rating generator stator insulation ageing state and software systems with the ultrasonic reflection method, the Journal of Sex Research article in early stage that the document relevant with the present invention also has only the present inventor to deliver before the application, the one, " research of big motor epoxy-mica stator insulation ultrasonic velocity ", mainly inquired into A type pulse echo method ultrasonic wave detecting system, study of the influence of the different insulation position of big stator winding conductor bars in electrical machines, and velocity of wave is with the Changing Pattern of insulation ag(e)ing to the detection ultrasonic velocity.The 2nd, " based on shelf depreciation and the big motor stator insulated aging characteristics of supercritical ultrasonics technology research "; Mainly be that (18KV, 300MW) more the thread-changing rod has carried out the multiple-factor accelerated aging test, the result that the different ageing steps of online rod have been carried out shelf depreciation and ultrasonic velocity test to No. 7 machines of Jiangsu Jian Bi power plant.
The method commonly used of high-rating generator stator insulation ageing state diagnosis at present is a measurement of partial discharge.The supersonic reflection method detection technique is at the existing supersonic detection device that is used for compound inslation inherent vices such as sleeve pipe, transformer, switch cubicle and cable of the application of insulation context of detection.This device comprises displacement transducer, sonac, with reference to parts such as displacement component, displacement electron element, reflectoscope, RS232 interface, PC and color monitors, can carry out colored C scanning to defective.
Though measurement of partial discharge is the high-rating generator stator insulation method for diagnosing status of using always, the method is easy to be subjected to the influence of interference such as on-the-spot electromagnetic wave, Harmonious Waves in Power Systems, and its accuracy is under some influence.
There are following deficiency in detection method and system that the ultrasonic reflection method is used for sleeve pipe, transformer, switch cubicle and cable etc.: one, the frequency of sonac is 5-15MHz, for the very big high-rating generator stator insulation of attenuation coefficient, the ultrasound wave that frequency is so high had just attenuated before detecting useful signal, and therefore existing detection method and system are not suitable for the detection of high-rating generator stator insulation.What two, obtain on the display of reflectoscope is ultrasound wave after the detection, only show and be greater than or less than zero portion waveshape, the waveform of this distortion can not be studied ultrasound wave is propagated the important parameters such as frequency that take place in material variation, has therefore lost the micromechanism of a lot of materials or the information that material changes.Three, this device can only detect insulation defect, can not assess its ageing state to producing defective zero defect insulation before.Four, Zhuan Zhi ingredient is too much, adds the use of reflectoscope, makes whole detection device heavy, is not suitable for the on-the-spot application that detects.
Three, summary of the invention
At defective or the deficiency that above-mentioned prior art exists, the present invention is intended to develop the ultrasonic reflection pick-up unit that is fit to high-rating generator stator insulation condition diagnosing and adopts the method for this device diagnosis high-rating generator stator insulation state.This detection method can realize following purpose: the condition diagnosing that, is applicable to the high-rating generator stator insulation; Two, detect and to obtain in stator insulation, propagating and at stator insulation one copper conductor interface or the ultrasonic reflection all-wave waveform of insulation defect place emission, guarantee all information of the insulating material microstructure change of carrying in the ultrasound wave; Three, can not only detect insulation defect, also can diagnose, to predict the also appearance of the most dangerous fast-developing insulation crackle of unexpected generation to the ageing state of (flawless) insulation before the generation insulation defect; Four, whole detection device satisfies the on-the-spot requirement that detects.
The essence of sonic propagation is the interaction of medium molecule, so the micro-variations of medium inside is depended in the propagation of sound wave (as ultrasonic propagation parameter and acoustic wave propagation path) to a great extent.The high-rating generator stator insulation is in ageing process, insulation expansion, it is loose that insulating material becomes, and microdefects such as air gap, layering, shelling and crackle occur, so ultrasonic propagation parameter of propagating in stator insulation or travel path may change because of the degree of aging of insulation is different.
Based on above theory, the technical solution used in the present invention is, a kind of ultrasonic reflection method pick-up unit of high-rating generator stator insulation condition diagnosing, comprise, the ultrasonic normal probe that couplant, frequency are 0.8MHz, the ultrasound wave generation of an exportable all-wave waveform and receiving trap, a notebook computer, it is characterized in that device also has the data collecting card that twin-channel sampling rate is 20Ms/S, wherein notebook computer has special software; Between ultrasonic normal probe and ultrasonic generation and the receiving trap, interconnect through concentric cable between ultrasonic generation and receiving trap and the data collecting card, interconnect through data line between data collecting card and the notebook computer;
Ultrasound wave takes place and the receiving trap transmission frequency is the synchronous electric pulse of 500kHz, electric pulse propagates into ultrasonic normal probe by concentric cable on the one hand synchronously, excite the piezoelectric chip vibration in the probe to produce ultrasound wave, frequency of ultrasonic is by the frequency decision of ultrasonic normal probe; Synchronously electric pulse on the other hand after trigger delay as the scanning trigger pip of data collecting card; The ultrasound wave that ultrasonic normal probe produces and is propagated in stator insulation in couplant impinges perpendicularly on the test product stator insulation; Propagate in stator insulation when ultrasound wave, running into defective will launch at the interface, and reflection wave is backpropagation in stator insulation, and is received by the hyperacoustic ultrasonic normal probe of emission; Ultrasound wave becomes electric impulse signal after ultrasonic normal probe receives, behind signal conditions such as ultrasound wave generation and receiving trap decay amplification, by the data collecting card digitizing, send into by data line in the special software of notebook computer, finish real-time demonstration, preservation and the analyzing and processing of ultrasound data by software.
Other characteristics of apparatus of the present invention are that described couplant is vaseline or silicone grease.
Described ultrasound wave takes place and receiving trap is the defectoscope of energy output ultrasonic wave all-wave.
Adopt the method for the ultrasonic reflection method pick-up unit diagnosis high-rating generator stator insulation state of above-mentioned high-rating generator stator insulation condition diagnosing, it is characterized in that, carry out in the following manner:
1) stator insulation for the treatment of the generator different slots of diagnosis carries out multimetering, judges that the reflecting interface type of ultrasound wave all-wave waveform is insulation-copper interface or insulation-air interface;
2) the ultrasound wave all-wave waveform that is judged as insulation-copper boundary reflection is used for adding up the minimum value and the mean value of the ultrasonics propagation parameter of every groove stator insulation;
3) there is rate in the ultrasound wave all-wave waveform that the is judged as insulation-air interface reflections defective that is used for adding up every groove stator insulation;
4) there is rate in the defective of the minimum value of the ultrasonics propagation parameter of the above-mentioned stator insulation that obtains and mean value and stator insulation, respectively with the database of notebook computer special software under the different ageing states minimum velocity of ultrasonic sound, average velocity of ultrasonic sound and the defective of stator insulation exist rate to compare, thereby reach the purpose of diagnosing insulation state.
Under the ground unrest of the on-the-spot 90dB of generator operation (A), 0～23 year generator (300MW of this device energy measurement operation, 18kV) the variation of the ultrasonics characterisitic parameter of stator insulation, the minimum dimension of detected insulation defect is 0.9mm, carries out effective state of insulation diagnosis.Ultrasound wave takes place and receiving trap (6) and data collecting card (7) integrated, makes system body partly realize the purpose of small portable, and volume is about 150mm * 150mm * 100mm, and weight is 2.5kg.This system has strong interference immunity, the accuracy height, and data processing is fast, and advantage such as be easy to carry is particularly suitable for the field diagnostic of high-rating generator stator insulation ageing state.
Four, description of drawings
Shown in Figure 1 is ultrasonic pulse reflection method stator insulation pick-up unit of the present invention;
Among the figure, the expression of each symbol is respectively: 1. tested stator bar; 2. couplant; 3. ultrasonic normal probe; 4. concentric cable; 5. ultrasound wave takes place and receiving trap; 6. data collecting card; 7. data line; 8. notebook computer.
Fig. 2 is the process flow diagram of special software of the present invention.
Five, embodiment
The present invention is described in further detail according to specific embodiment that technical scheme of the present invention is finished below in conjunction with accompanying drawing and inventor.
Referring to accompanying drawing, the ultrasonic reflection method pick-up unit of high-rating generator stator insulation condition diagnosing of the present invention, the couplant 2 that comprises couplant vaseline or silicone grease, a frequency is 0.8MHz, diameter is the ultrasonic normal probe 3 of 15mm, the ultrasound wave of an exportable all-wave waveform takes place and receiving trap 5, a data collecting card 6 and the notebook computer 8 that has special software that twin-channel sampling rate is 20Ms/S, between ultrasonic normal probe 3 and ultrasonic generation and the receiving trap 5, interconnect through concentric cable between ultrasonic generation and receiving trap 5 and the data collecting card 6, interconnect through data line between data collecting card 6 and the notebook computer 8;
1. couplant 2 is in order to reduce gas between ultrasonic normal probe 3 and the tested stator bar 1 to the decay of ultrasonic energy;
2. the frequency of ultrasonic normal probe 3 and diameter must be fit to the scene of large generator stator bar insulation and detect, in the ultrasonic normal probe of standby three different frequencies and diameter, can choose one wantonly, the needs when detecting with the insulation against ground of satisfying different capabilities generator stator bar different-thickness;
3. ultrasonic normal probe 3 self is furnished with the concentric cable 4 with ultrasonic normal probe one, also has two 3m, a cable in stock and the connector that 15m is long simultaneously, so that satisfy the needs of on-the-spot various measuring distances;
4. be that the ultrasound wave that integrates takes place and receiving trap 5 and data collecting card 6 in the empty frame, volume is about 150 * 150 * 100mm, and weight is 2.5kg;
5. ultrasound wave generation and receiving trap 5 are defectoscopes of energy output ultrasonic wave all-wave;
6. data collecting card 6 is virtual oscilloscopes, its trigger pip is that the excitation ultrasound normal probe 3 that ultrasound wave takes place and receiving trap 5 produces produces hyperacoustic electric impulse signal, so pass through data line 7 control data capture cards 6 by notebook computer 8, can the hyperacoustic transmitted wave of real-time display system and the reflection wave when in insulation, propagating, the precision in travel-time has reached 0.5ns.
The principle of work of the ultrasonic reflection method detection system of high-rating generator stator insulation condition diagnosing is: ultrasound wave takes place and receiving trap 5 transmission frequencies are the synchronous electric pulse of 500kHz, electric pulse propagates into ultrasonic normal probe 3 by concentric cable 4 on the one hand synchronously, excite the piezoelectric chip vibration in the probe to produce ultrasound wave, frequency of ultrasonic is by the frequency decision of ultrasonic normal probe 3; Synchronously electric pulse on the other hand after trigger delay as the scanning trigger pip of data collecting card 6 (virtual oscilloscope).The ultrasound wave that ultrasonic normal probe 3 produces and is propagated in stator insulation in couplant 2 impinges perpendicularly on test product 1 stator bar (insulation).When ultrasound wave is propagated in stator insulation, run into defective (insulation-air interface) or run into copper conductor (insulation-copper conductor interface), will launch at the interface, reflection wave is backpropagation in stator insulation, and is received by the hyperacoustic ultrasonic normal probe 3 of emission.Ultrasound wave becomes electric impulse signal after ultrasonic normal probe 3 receives, behind signal conditions such as ultrasound wave generation and receiving trap 5 decay amplifications, by data collecting card 6 digitizings, send into the special software of notebook computer 8 by data line 7, finish the processing such as real-time demonstration, preservation and analysis of ultrasound data.
The flow process of this special software is referring to Fig. 2.
Method with ultrasonic reflection method detection technique diagnosis high-rating generator stator insulation state is: with the ultrasonic reflection method detection system of high-rating generator stator insulation condition diagnosing, the stator insulation for the treatment of the generator different slots of diagnosis carries out multimetering, judges that the reflecting interface type of ultrasound wave all-wave waveform is insulation-copper interface or insulation-air interface.The ultrasound wave waveform that is judged as insulation-copper boundary reflection is used for adding up the minimum value and the mean value of the ultrasonics propagation parameter of every groove stator insulation; There is rate in the defective that the ultrasound wave waveform that is judged as insulation-air interface reflections is used for adding up every groove stator insulation.These stator insulation ultrasonics parameters that obtain are compared with the thresholding of different insulative ageing state ultrasonics relevant parameter in the database of notebook computer (8) special software, thereby reach the purpose of diagnosing insulation state.
Claims (4)
1. the ultrasonic reflection method pick-up unit of a high-rating generator stator insulation condition diagnosing, comprise, the ultrasonic normal probe [3] that couplant [2], frequency are 0.8MHz, the ultrasound wave of an exportable all-wave waveform takes place and receiving trap [5], a notebook computer [8], it is characterized in that, device also has the data collecting card [6] that twin-channel sampling rate is 20Ms/S, and wherein notebook computer [8] has special software; Between ultrasonic normal probe [3] and ultrasonic generation and the receiving trap [5], interconnect through concentric cable [4] between ultrasonic generation and receiving trap [5] and the data collecting card [6], interconnect through data line [7] between data collecting card [6] and the notebook computer [8];
Ultrasound wave takes place and receiving trap [5] transmission frequency is the synchronous electric pulse of 500kHz, electric pulse propagates into ultrasonic normal probe [3] by concentric cable [4] on the one hand synchronously, excite the piezoelectric chip vibration in the probe to produce ultrasound wave, frequency of ultrasonic is by the frequency decision of ultrasonic normal probe [3]; Synchronously electric pulse on the other hand after trigger delay as the scanning trigger pip of data collecting card [6]; The ultrasound wave that ultrasonic normal probe [3] produces and is propagated in stator insulation in couplant [2] impinges perpendicularly on test product [1] stator insulation; Propagate in stator insulation when ultrasound wave, running into defective will launch at the interface, and reflection wave is backpropagation in stator insulation, and is received by the hyperacoustic ultrasonic normal probe of emission [3]; Ultrasound wave becomes electric impulse signal after ultrasonic normal probe [3] receives, after ultrasound wave generation and the conditioning of receiving trap [5] decay amplifying signal, by data collecting card [6] digitizing, send in the special software of notebook computer [8] by data line [7], finish real-time demonstration, preservation and the analyzing and processing of ultrasound data by software.
2. the ultrasonic reflection method pick-up unit of high-rating generator stator insulation condition diagnosing as claimed in claim 1 is characterized in that described couplant [2] is vaseline or silicone grease.
3. the ultrasonic reflection method pick-up unit of high-rating generator stator insulation condition diagnosing as claimed in claim 1 is characterized in that, described ultrasound wave takes place and receiving trap [5] is the defectoscope of energy output ultrasonic wave all-wave.
4. adopt the method for the ultrasonic reflection method pick-up unit diagnosis high-rating generator stator insulation state of the described high-rating generator stator insulation of claim 1 condition diagnosing, it is characterized in that, carry out in the following manner:
1) stator insulation for the treatment of the generator different slots of diagnosis carries out multimetering, judges that the reflecting interface type of ultrasound wave all-wave waveform is insulation-copper interface or insulation-air interface;
2) the ultrasound wave all-wave waveform that is judged as insulation-copper boundary reflection is used for adding up the minimum value and the mean value of the ultrasonics propagation parameter of every groove stator insulation;
3) there is rate in the ultrasound wave all-wave waveform that the is judged as insulation-air interface reflections defective that is used for adding up every groove stator insulation;
4) there is rate in the defective of the minimum value of the ultrasonics propagation parameter of the above-mentioned stator insulation that obtains and mean value and stator insulation, respectively with the database of notebook computer special software under the different ageing states minimum velocity of ultrasonic sound, average velocity of ultrasonic sound and the defective of stator insulation exist rate to compare, thereby reach the purpose of diagnosing insulation state.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02139424 CN1204410C (en) | 2002-09-13 | 2002-09-13 | Ultrasonic reflection detecting device and mehtod for diagnosis of insulation state of stator for large electric generator |
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| CN 02139424 CN1204410C (en) | 2002-09-13 | 2002-09-13 | Ultrasonic reflection detecting device and mehtod for diagnosis of insulation state of stator for large electric generator |
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| CN1402014A CN1402014A (en) | 2003-03-12 |
| CN1204410C true CN1204410C (en) | 2005-06-01 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7765181B2 (en) | 2001-12-18 | 2010-07-27 | Shawn Thomas | Web-based asset management |
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| JP4121430B2 (en) * | 2003-08-08 | 2008-07-23 | 三菱電機株式会社 | Insulation diagnosis method for electrical equipment |
| CN101369003B (en) * | 2008-10-10 | 2011-01-19 | 上海奥波电子有限公司 | Electric motor stator scanning detection apparatus |
| CN101644745B (en) * | 2009-09-04 | 2011-09-21 | 西安交通大学 | Method for dual-frequency ultrasonic detection of defect of generator stator insulator |
| CN103076542A (en) * | 2011-10-25 | 2013-05-01 | 章啸 | Partial discharge ultrasonic wave detection device |
| US9658192B2 (en) * | 2012-01-23 | 2017-05-23 | Siemens Corporation | Insulation defect detection of high voltage generator stator core |
| EP2690422B1 (en) * | 2012-07-25 | 2020-04-08 | Ansaldo Energia IP UK Limited | Method for monitoring machines with rotating shafts |
| CN103412049B (en) * | 2013-07-15 | 2016-01-13 | 清华大学 | A kind of high temperature steam injection defect of pipeline monitoring method |
| CN105203928A (en) * | 2015-08-07 | 2015-12-30 | 北重阿尔斯通（北京）电气装备有限公司 | Device and method for detecting insulation integrity of motor stator coil bar |
| CN111257416A (en) * | 2020-02-03 | 2020-06-09 | 天津大学 | Method for detecting internal defects of extra-high voltage insulating pull rod |
| CN111257418A (en) * | 2020-02-03 | 2020-06-09 | 天津大学 | Internal defect detection device for extra-high voltage insulation pull rod |
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2002
- 2002-09-13 CN CN 02139424 patent/CN1204410C/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7765181B2 (en) | 2001-12-18 | 2010-07-27 | Shawn Thomas | Web-based asset management |
| US8266124B2 (en) | 2001-12-18 | 2012-09-11 | Caldvor Acquisitions Ltd., Llc | Integrated asset management |
| US8321468B2 (en) | 2001-12-18 | 2012-11-27 | Caldvor Acquisitions Ltd., Llc | Web-based asset management |
| US8484248B2 (en) | 2001-12-18 | 2013-07-09 | Caldvor Acquisitions Ltd., Llc | Web-based asset management |
| US8631014B2 (en) | 2001-12-18 | 2014-01-14 | Caldvor Acquisitions Ltd., Llc | Method and system for integrated asset management |
| US8825712B2 (en) | 2001-12-18 | 2014-09-02 | Caldvor Acquisitions Ltd., Llc | Web-based asset management |
| US8856646B2 (en) | 2001-12-18 | 2014-10-07 | Caldvor Acquisitions Ltd., Llc | Asset transition project management |
| US9348914B2 (en) | 2001-12-18 | 2016-05-24 | Caldvor Acquisitions Ltd., Llc | Web-based asset management |
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