CN102841137A - Compensating method for detecting interference signal through rotating eddy current - Google Patents
Compensating method for detecting interference signal through rotating eddy current Download PDFInfo
- Publication number
- CN102841137A CN102841137A CN2012103735763A CN201210373576A CN102841137A CN 102841137 A CN102841137 A CN 102841137A CN 2012103735763 A CN2012103735763 A CN 2012103735763A CN 201210373576 A CN201210373576 A CN 201210373576A CN 102841137 A CN102841137 A CN 102841137A
- Authority
- CN
- China
- Prior art keywords
- signal
- eddy current
- probe
- compensation
- undesired
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Abstract
The invention discloses a compensating method for detecting an interference signal through a rotating eddy current. A signal acquired by an absolute probe in a rotating eddy current detecting device is weighted to a signal acquired by a difference probe; a fake defect signal generated by eccentricity is counteracted; the gain change caused by lift-off effect is compensated; the influence of an eddy current interference signal formed by the rotating eddy current detecting device during a rotating detection period because of periodic vibration or eccentricity is eliminated; the false is eliminated and the true is retained; the possibility of erroneous judgment is effectively reduced; and the detection precision is greatly increased.
Description
Technical field
The present invention relates to a kind of lossless detection method, particularly relate to a kind of rotating vortex and detect the undesired signal compensation method.
Background technology
The rotating vortex pick-up unit is in the rotation testing process; Periodic vibration or eccentric meeting form the eddy current undesired signal; This eddy current undesired signal can form definite shape, have certain amplitude and angle on the eddy current impedance plane undesired signal figure; Be the false defect signal, the frequency response that the frequency response of this signal produces the difference detector in the rotating vortex device far below longitudinal crack.
Summary of the invention
The objective of the invention is to overcome the deficiency of prior art, provide a kind of rotating vortex to detect the undesired signal compensation method, eliminate the rotating vortex probe in the rotation testing process since periodic vibration or the eccentric eddy current undesired signal that forms influence.
The technical solution adopted for the present invention to solve the technical problems is: a kind of rotating vortex detects the undesired signal compensation method; It is characterized in that, in the signal that signal weighting to the difference detector that the absolute probe in the eddy current whirligig is picked up picks up, offset because the false defect signal of generations such as off-centre, vibration; Compensation is because the change in gain that Lift-off effect produces; Implementation step is: a. at first is provided with circumferential synchronizing signal, is used to do auxiliary signal; B. the rotating vortex sensor is in the rotation testing process, and periodic vibration or eccentric meeting form eddy current undesired signal, this eddy current undesired signal can form definite shape, have certain amplitude and angle on the eddy current impedance plane undesired signal figure; C. adopt single-frequency eddy current and difference, absolute sensor to pick up the eddy current response signal on the time domain synchronously; And according to its correlativity; Setting up mathematical model, is a compensation cycle with 360 degree specifically, promptly with the measured value of absolute signal signal for referencial use; Revise the non-crackle signal response of differential signal, even differential signal obtains the impedance diagram that makes zero all the time at the zero defect place; D. when the crackle signal produces; According to the instant circumferential position of living in of probe; Make dynamic gain compensation, reach the beneficial effect of eliminating the false and retaining the true, its total effect is equivalent to multifrequency Eddy removal periodic jamming signals and compensating for periodic is lifted from the influence of signal to the flaw indication amplitude.Described circumferential synchronizing signal is that probe whenever circles along the cylindrical work rotation, by providing a switching pulse signal near switch, the start bit of expression probe circular motion.Probe possibly not be just round along the track of cylindrical work rotation, and perhaps the circularity of workpiece is bad, and perhaps workpiece/probe is shaken relatively; It is unstable from the distance of surface of the work to cause popping one's head in; Influenced the variation of probe pickoff signals size, need carry out the dynamic gain compensation in order to remedy this variation, described dynamic gain is compensated for as; In the level amplifying circuit of back, lifting from degree according to probe compensates signal amplitude; Compensated curve can confirm that the back experiment provide in condition of work, be generally non-linear, like the maximal value of lifting from eddy current signal, the minimum value of measuring each compensation cycle of absolute passage; Simulate a compensated curve then, with this penalty coefficient as corresponding circumferential position differential detection signal.
The invention has the beneficial effects as follows; A kind of rotating vortex detects the undesired signal compensation method; In the signal that signal weighting to the difference detector that absolute probe in the rotating vortex pick-up unit is picked up picks up, offset because the eccentric false defect signal that produces compensates because the change in gain that Lift-off effect produces; Eliminate the rotating vortex pick-up unit in the rotation testing process since periodic vibration or the eccentric eddy current undesired signal that forms influence; Eliminate the false and retain the true, effectively reduce the possibility of erroneous judgement, improve accuracy of detection greatly.
Below in conjunction with embodiment the present invention is done further explain, be not limited to embodiment but a kind of rotating vortex of the present invention detects the undesired signal compensation method.
Embodiment
Embodiment; A kind of rotating vortex of the present invention detects the undesired signal compensation method, in the signal that signal weighting to the difference detector that the absolute probe in the eddy current whirligig is picked up picks up, offsets because the eccentric false defect signal that produces; Compensation is because the change in gain that Lift-off effect produces; Implementation step is: a. at first is provided with circumferential synchronizing signal, is used to do auxiliary signal; B. the rotating vortex sensor is in the rotation testing process, and periodic vibration or eccentric meeting form eddy current undesired signal, this eddy current undesired signal can form definite shape, have certain amplitude and angle on the eddy current impedance plane undesired signal figure; C. adopt single-frequency eddy current and difference, absolute sensor to pick up the eddy current response signal on the time domain synchronously; And according to its correlativity; Setting up mathematical model, is a compensation cycle with 360 degree specifically, promptly with the measured value of absolute signal signal for referencial use; Revise the non-crackle signal response of differential signal, even differential signal obtains the impedance diagram that makes zero all the time at the zero defect place; D. when the crackle signal produces; According to the instant circumferential position of living in of probe; Make dynamic gain compensation, reach the beneficial effect of eliminating the false and retaining the true, its total effect is equivalent to multifrequency Eddy removal periodic jamming signals and compensating for periodic is lifted from the influence of signal to the flaw indication amplitude.
The foregoing description only is used for further specifying a kind of rotating vortex of the present invention and detects the undesired signal compensation method; But the present invention is not limited to embodiment; Every foundation technical spirit of the present invention all falls in the protection domain of technical scheme of the present invention any simple modification, equivalent variations and modification that above embodiment did.
Claims (3)
1. a rotating vortex detects the undesired signal compensation method; It is characterized in that: in the signal that signal weighting to the difference detector that the absolute probe in the eddy current whirligig is picked up picks up; Offset because the false defect signal of generations such as off-centre, vibration; The change in gain that compensation produces owing to Lift-off effect, implementation step is:
A. at first, circumferential synchronizing signal is set, is used to do auxiliary signal;
B. the rotating vortex sensor is in the rotation testing process, and periodic vibration or eccentric meeting form eddy current undesired signal, this eddy current undesired signal can form definite shape, have certain amplitude and angle on the eddy current impedance plane undesired signal figure;
C. adopt single-frequency eddy current and difference, absolute sensor to pick up the eddy current response signal on the time domain synchronously; And according to its correlativity; Setting up mathematical model, is a compensation cycle with 360 degree specifically, promptly with the measured value of absolute signal signal for referencial use; Revise the non-crackle signal response of differential signal, even differential signal obtains the impedance diagram that makes zero all the time at the zero defect place;
D. when the crackle signal produces; According to the instant circumferential position of living in of probe; Make dynamic gain compensation, reach the beneficial effect of eliminating the false and retaining the true, its total effect is equivalent to multifrequency Eddy removal periodic jamming signals and compensating for periodic is lifted from the influence of signal to the flaw indication amplitude.
2. a kind of rotating vortex according to claim 1 detects the undesired signal compensation method; It is characterized in that: described circumferential synchronizing signal is that probe whenever circles along the cylindrical work rotation; By providing a switching pulse signal near switch, the start bit of expression probe circular motion.
3. a kind of rotating vortex according to claim 1 detects the undesired signal compensation method; It is characterized in that: described dynamic gain is compensated for as; In the level amplifying circuit of back, lifting from degree according to probe compensates signal amplitude; Compensated curve can confirm that the back experiment provide in condition of work, be generally non-linear, like the maximal value of lifting from eddy current signal, the minimum value of measuring each compensation cycle of absolute passage; Simulate a compensated curve then, with this penalty coefficient as corresponding circumferential position differential detection signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210373576.3A CN102841137B (en) | 2012-09-30 | 2012-09-30 | Compensating method for detecting interference signal through rotating eddy current |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210373576.3A CN102841137B (en) | 2012-09-30 | 2012-09-30 | Compensating method for detecting interference signal through rotating eddy current |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102841137A true CN102841137A (en) | 2012-12-26 |
| CN102841137B CN102841137B (en) | 2014-12-03 |
Family
ID=47368691
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210373576.3A Active CN102841137B (en) | 2012-09-30 | 2012-09-30 | Compensating method for detecting interference signal through rotating eddy current |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102841137B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103399083A (en) * | 2013-08-27 | 2013-11-20 | 南昌航空大学 | Method for restraining lift-off effect of impulse eddy current testing |
| CN103808795A (en) * | 2014-02-11 | 2014-05-21 | 宁波工程学院 | Novel impulse detection algorithm |
| CN106404899A (en) * | 2016-08-29 | 2017-02-15 | 爱德森（厦门）电子有限公司 | Eddy current detection uplift shake compensation method |
| CN109115867A (en) * | 2018-07-18 | 2019-01-01 | 清华大学 | Plane Rotation Eddy Current Testing Transducer and detection method |
| CN109115866A (en) * | 2018-07-18 | 2019-01-01 | 清华大学 | Rotate in a circumferential direction point type eddy current sensor and detection method |
| CN112129830A (en) * | 2020-09-02 | 2020-12-25 | 中国人民解放军空军工程大学航空机务士官学校 | Aircraft metal structure burn detection method based on eddy current conductivity |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4383218A (en) * | 1978-12-29 | 1983-05-10 | The Boeing Company | Eddy current flow detection including compensation for system variables such as lift-off |
| CN101034082A (en) * | 2007-01-11 | 2007-09-12 | 丁昱程 | Technology for eliminating detecting blind-area in end or edge for vortex detecting |
| US20080278157A1 (en) * | 2004-05-21 | 2008-11-13 | Jason Scott Zimmerman | Eddy current probe |
| CN101413923A (en) * | 2007-06-12 | 2009-04-22 | 通用电气检查技术有限公司 | Automatic lift-off compensation for pulsed eddy current inspection |
| CN202171585U (en) * | 2011-06-22 | 2012-03-21 | 厦门艾帝尔电子科技有限公司 | Rotary vortex flow detecting system |
-
2012
- 2012-09-30 CN CN201210373576.3A patent/CN102841137B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4383218A (en) * | 1978-12-29 | 1983-05-10 | The Boeing Company | Eddy current flow detection including compensation for system variables such as lift-off |
| US20080278157A1 (en) * | 2004-05-21 | 2008-11-13 | Jason Scott Zimmerman | Eddy current probe |
| CN101034082A (en) * | 2007-01-11 | 2007-09-12 | 丁昱程 | Technology for eliminating detecting blind-area in end or edge for vortex detecting |
| CN101413923A (en) * | 2007-06-12 | 2009-04-22 | 通用电气检查技术有限公司 | Automatic lift-off compensation for pulsed eddy current inspection |
| CN202171585U (en) * | 2011-06-22 | 2012-03-21 | 厦门艾帝尔电子科技有限公司 | Rotary vortex flow detecting system |
Non-Patent Citations (3)
| Title |
|---|
| GUI YUN TIAN ET AL.: "Defect classification using a new feature for pulsed eddy current sensors", 《NDT&E INTERNATIONAL》 * |
| UDPA L ET AL: "Automated analysis of eddy current signals in steam generator tube inspection", 《6TH WORLD CONFERENCE ON NONDESTRUCTIVE EVALUATION》 * |
| 刘涛: "钢管旋转式涡流探伤提离效应补偿新方法", 《物理测试》 * |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103399083A (en) * | 2013-08-27 | 2013-11-20 | 南昌航空大学 | Method for restraining lift-off effect of impulse eddy current testing |
| CN103808795A (en) * | 2014-02-11 | 2014-05-21 | 宁波工程学院 | Novel impulse detection algorithm |
| CN103808795B (en) * | 2014-02-11 | 2017-05-31 | 湖州师范学院 | A kind of novel pulse detection algorithm |
| CN106404899A (en) * | 2016-08-29 | 2017-02-15 | 爱德森（厦门）电子有限公司 | Eddy current detection uplift shake compensation method |
| CN109115867A (en) * | 2018-07-18 | 2019-01-01 | 清华大学 | Plane Rotation Eddy Current Testing Transducer and detection method |
| CN109115866A (en) * | 2018-07-18 | 2019-01-01 | 清华大学 | Rotate in a circumferential direction point type eddy current sensor and detection method |
| CN112129830A (en) * | 2020-09-02 | 2020-12-25 | 中国人民解放军空军工程大学航空机务士官学校 | Aircraft metal structure burn detection method based on eddy current conductivity |
| CN112129830B (en) * | 2020-09-02 | 2023-09-12 | 中国人民解放军空军工程大学航空机务士官学校 | Airplane metal structure burn detection method based on eddy current conductivity |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102841137B (en) | 2014-12-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102841137B (en) | Compensating method for detecting interference signal through rotating eddy current | |
| JP5253615B2 (en) | Method and apparatus for detecting cracks in metallic materials | |
| CN107388048B (en) | Sensor for distinguishing defects of inner wall and outer wall of pipeline magnetic leakage inner detection and identification evaluation method | |
| CN108344798B (en) | Double-frequency excitation circular eddy current probe and method for detecting thick-wall deep crack defects | |
| TW200951456A (en) | Capacitive sensing with high-frequency noise reduction | |
| CN105891323A (en) | Eddy probe array for detecting pipeline deformation | |
| NO20053506D0 (en) | Procedure for monitoring wall thickness | |
| CN102759567A (en) | Eddy current testing recognition and evaluation method for defects of inner wall and outer wall of steel pipe under direct current magnetization | |
| WO2010118091A3 (en) | Line noise analysis and detection and measurement error reduction | |
| US8372252B2 (en) | Method for setting a distance between an electrode and a workpiece | |
| CN103954684A (en) | Method for nondestructive testing by use of change rate of magnetic flux leakage | |
| CN109141325A (en) | The contactless measurement and device of metal surface coated layer thickness | |
| CN110030498B (en) | Axial magnetic field signal compensation system for internal detection of ferromagnetic pipeline defects | |
| CN110187001B (en) | Defect detection method adopting surface magnetic conductance technology | |
| CN105973177A (en) | Back drill stump nondestructive detection method and PCB nondestructive detection method | |
| CN201837351U (en) | Device for detecting angle of discontinuous cone-shaped rotator | |
| CN103399083A (en) | Method for restraining lift-off effect of impulse eddy current testing | |
| CN102879480A (en) | Method for delaying self-adaptive ultrasonic phased array wedge | |
| CN106404899A (en) | Eddy current detection uplift shake compensation method | |
| CN104792863A (en) | Porcelain vase damage automatic detection device | |
| CN205643247U (en) | Alternating current magnetic field detection pen formula probe | |
| JP2013224916A (en) | Grinding burn determination device and grinding burn determination method | |
| CN104614444A (en) | Method for improving electromagnetic ultrasonic detection precision | |
| CN101979955A (en) | Device for detecting discontinuous conical rotating body angle | |
| CN106442712A (en) | Device and method for automatically calibrating eddy current detection sensitivity |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |