CN203630276U - Insulator sample aging degree detection device - Google Patents
Insulator sample aging degree detection device Download PDFInfo
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- CN203630276U CN203630276U CN201320683836.7U CN201320683836U CN203630276U CN 203630276 U CN203630276 U CN 203630276U CN 201320683836 U CN201320683836 U CN 201320683836U CN 203630276 U CN203630276 U CN 203630276U
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Abstract
The invention discloses an insulator sample aging degree detection device and solves problems that a magnetic resonance detection magnet for insulator aging degree is low in magnetic field uniformity, and a surrounding environment is influenced by a stray magnetic field. The insulator sample aging degree detection device comprises that: twelve cube-shaped magnet sub-modules (1) with identical volume and magnetic material are selected to magnetized so that all the cube-shaped magnet sub-modules are identical in magnetizing intensity and magnetizing direction; the twelve cube-shaped magnet sub-modules are evenly arranged on an identical circumference in equal radian intervals; a detection coil (15) is arranged at the position of the center of a circle at which the identical circumference, on which the twelve cube-shaped magnet sub-modules are evenly arranged, is positioned, and signals in the detection coil are detected and analyzed; electromagnetic excitation is performed on insulator samples, and the generated magnetic resonance induction attenuation signals are processed via a preamplifier, a frequency mixer and an analog-to-digital converter in order; and parameters like height of each characteristic spectral line on a spectrogram are observed and analyzed and compared with standard data so that judgment of insulator aging degree is realized.
Description
Technical field
The present invention relates to a kind of magnetic resonance permanent magnet pick-up unit of the relaxation behavior for detection of insulator sample, particularly a kind of pick-up unit for detection of insulator sample Degree of Ageing.
Background technology
The principal ingredient of conventional silicon rubber compound insulator is dimethyl silicone polymer, its molecule take repeat silicon oxygen bond Si-O as main chain, on Si atom, be directly connected with the polymkeric substance such as methyl, vinyl, around the compact arranged nonpolar methyl group of Si-O main chain to surface orientation, shield the strong polarity of Si-O, made silastic surface present good hydrophobic nature.Be subject to the impact of extraneous rugged surroundings or corona discharge etc., insulator occurs aging, the part group being connected with main chain Si atom is come off, the state of the hydrogen atoms 1H of institute changes, and mr techniques is according to the electromagnetic property of 1H, physics and chemistry character and the residing molecule environment thereof of 1H in research material, and analyze correlation molecule structure.Adopt magnetic resonance method to analyze the variation of silicon rubber insulator 1H state, can indirectly realize the quantitative and qualitative analysis of sample Degree of Ageing is characterized.At present, the online test method of composite insulator umbrella skirt material mainly contains infrared imaging method and ultrasonic Detection Method etc.Infrared imaging method, this method detects for heatings such as wire, joint, sleeve pipes and the heating of composite insulator local anomaly detects, and most insulating material that caused by electric field damage relevant with temperature.Dielectric loss when shelf depreciation leakage current flows through megohmite insulant or ohmic loss all can cause that insulator local temperature raises.The infrared ray sending by observation hot localised points can be found some defect.The shortcoming of this method is the impact that the high and temperature survey of instrument cost is subject to sunlight, strong wind, moisture, environment temperature and some and can causes the factors such as insulator surface temperature sharply changes.Ultrasonic Detection Method, based on ultrasound wave the communication process that enters into another kind of medium from a kind of medium can reflect at the interface of two media, the principle of refraction and mode conversion (P-wave And S conversion), the reflection wave of the pulse ultrasonic wave sending by reception ultrasonic generator (being called transducer) in the time entering insulator medium and pass insulator medium limits between the lane place of insulator.In the time there is " cracking " in insulator, on the time shaft that receives reflection wave, will there is the reflection wave of this defect, can judge the concrete condition of defect in insulator by the size and location of this defect waves on time shaft.Ultrasound examination is simple to operate, safe and reliable, antijamming capability is strong, mainly for detection of the crackle of core rod of insulator.But there is the problems such as coupling, decay and ultrasonic transducer performance in it.In addition, when actual measurement often there is corona in high-pressure side gold utensil, and the background noise of generation can flood the sound wave that defects of insulator sends, and is not suitable for Site Detection, is relatively applicable to enterprise and produces online detection and laboratory verification etc.Known the Ageing of Insulators degree magnetic resonance detection probe is made up of minitype permanent-magnet and radio-frequency coil.Tested insulator sample is positioned among magnetic field of permanent magnet, hydrogen nuclei generation magnetic polarization in sample, radio-frequency coil produces a radio-frequency pulse magnetic field vertical with permanent magnet magnetic field direction in sample area, pull the static magnetization intensity vector of sample down 90 degree, remove behind radio-frequency pulse magnetic field the two ends at radio-frequency coil in the process of described magnetization intensity vector return to primitive age state and produce induction electromotive force, it is magnetic resonance signal, this signal is carried out to the complementary operation based on T2 (T2), obtain T2 spectrum, by can determine the linked network time limit of tested insulator sample to the analysis of line structure." a kind of magnetic resonance sensors for composite insulator umbrella skirt aging Non-Destructive Testing " of the patent No. 201210248887.7 introduced the Ageing of Insulators degree magnetic resonance pick-up unit of the permanent magnet staggered relatively based on two and planar coil, can adapt to the insulator sample of different-thickness by the distance between two permanent magnets of mechanical adjustment.Because described magnet forms for adopting conventional method monomer to magnetize, its magnetic field homogeneity in desired target area is not high, can affect the magnetized homogeneity of sample, and then the detection signal-to-noise ratio of reduction magnetic resonance signal, increase the detection time of the Ageing of Insulators degree, in addition, adopt the adjustable magnet combination mode of spacing, although can increase the applicability of described pick-up unit, but in the middle of can making, the magnetic flux density in magnetic field changes, and then magnetic resonance frequency changes, just need to readjust the resonant frequency of radio-frequency coil, increase the complicacy that device uses.No matter be in laboratory or at substation field, the existence of a high-intensity magnetic field magnet can bring certain potential safety hazard to the electrical equipment of surrounding normal work, particularly in the time that magnet is moved.
Summary of the invention
The invention provides a kind of insulator sample Degree of Ageing pick-up unit, the uniformity of magnetic field that has solved existing the Ageing of Insulators degree magnetic resonance detection magnet is not high, and the technical matters of the impact of stray magnetic field on surrounding environment.
The present invention solves above technical matters by the following technical programs:
A kind of insulator sample Degree of Ageing pick-up unit, comprise detected insulator sample, magnetic test coil and 12 magnetizing directions and all identical cube shaped magnet submodules of intensity that magnetize, 12 identical cube shaped magnet submodules of volume are to wait radian compartment of terrain to be distributed on same circumference, if choose the magnetizing direction of one of them cube shaped magnet submodule as benchmark, on this same circumference, the magnetizing direction of the each cube shaped magnet submodule of arranging successively is along clockwise direction to rotate successively along clockwise direction 60 degree, on the home position of justifying at 12 these uniform same circumference places of cube shaped magnet submodule, be provided with magnetic test coil, on the central shaft of magnetic test coil, be provided with detected insulator sample, one end ground connection of magnetic test coil, the other end of magnetic test coil is connected with one end of impedance matching electric capacity, be parallel with frequency tuning electric capacity at the two ends of magnetic test coil, one end and series diode that the other end of impedance matching electric capacity is 1/4 wavelength lossless line with length are respectively connected one end of pipe, length is that the other end of 1/4 wavelength lossless line is connected one end of pipe with input end and the parallel diode of prime amplifier respectively, the other end ground connection of parallel diode to pipe, the output terminal of prime amplifier is connected with one end of gate controlled switch, the other end of gate controlled switch is connected with the first input end of frequency mixer, the output terminal of frequency mixer is connected with the input end of analog to digital converter, the output terminal of analog to digital converter is connected with the input end of computing machine, the output terminal of computing machine is connected with the input end of radio-frequency signal source, the output terminal of radio-frequency signal source is connected with the second input end of frequency mixer and the input end of sampling switch respectively, the output terminal of sampling switch is connected with the input end of power amplifier, the output terminal of power amplifier is connected the other end of pipe with series diode.
Described detected insulator sample is torus shape, detected insulator sample be arranged on magnetic test coil directly over.
The invention provides a kind of permanent magnet, this magnet not only can detect the Degree of Ageing of insulator, and can improve the magnetic field homogeneity of sample detection target area, and there is lower stray magnetic field, the uniformity of magnetic field that has overcome existing the Ageing of Insulators degree magnetic resonance detection magnet is not high, and the impact of stray magnetic field on surrounding environment.
Accompanying drawing explanation
Fig. 1 is structural representation of the present invention;
Fig. 2 is metering circuit structural representation of the present invention;
Fig. 3 is that 12 cube shaped magnet submodules 1 of the present invention are at the magnetic field structure schematic diagram of overlooking in direction;
Fig. 4 is the structural representation in the magnetic field of magnetizing of cube shaped magnet submodule 1 of the present invention.
Embodiment
A kind of insulator sample Degree of Ageing pick-up unit, comprise detected insulator sample 17, 15 and 12 magnetizing directions of magnetic test coil and all identical cube shaped magnet submodules 1 of intensity that magnetize, 12 identical cube shaped magnet submodules 1 of volume are to wait radian compartment of terrain to be distributed on same circumference, if choose the magnetizing direction X of one of them cube shaped magnet submodule 1 as benchmark, on this same circumference, the magnetizing direction of the each cube shaped magnet submodule of arranging successively is along clockwise direction to rotate successively along clockwise direction 60 degree, on the home position of justifying at 12 these uniform same circumference places of cube shaped magnet submodule 1, be provided with magnetic test coil 15, on the central shaft of magnetic test coil 15, be provided with detected insulator sample 17, one end ground connection of magnetic test coil 15, the other end of magnetic test coil 15 is connected with one end of impedance matching electric capacity 16, be parallel with frequency tuning electric capacity 3 at the two ends of magnetic test coil 15, one end and series diode that the other end of impedance matching electric capacity 16 is 1/4 wavelength lossless line 4 with length are respectively connected managing one end of 7, length is that the other end of 1/4 wavelength lossless line 4 is connected managing one end of 6 with input end and the parallel diode of prime amplifier 5 respectively, parallel diode is to managing 6 other end ground connection, the output terminal of prime amplifier 5 is connected with one end of gate controlled switch 10, the other end of gate controlled switch 10 is connected with the first input end of frequency mixer 11, the output terminal of frequency mixer 11 is connected with the input end of analog to digital converter 12, the output terminal of analog to digital converter 12 is connected with the input end of computing machine 14, the output terminal of computing machine 14 is connected with the input end of radio-frequency signal source 13, the output terminal of radio-frequency signal source 13 is connected with the second input end of frequency mixer 11 and the input end of sampling switch 9 respectively, the output terminal of sampling switch 9 is connected with the input end of power amplifier 8, the output terminal of power amplifier 8 is connected managing 7 the other end with series diode.
Described detected insulator sample 17 is torus shape, detected insulator sample 17 be arranged on magnetic test coil 15 directly over.
The technical solution adopted for the present invention to solve the technical problems is: choose 12 cube shaped permanent magnets that the length evenly magnetizing is identical, its magnetizing direction is all vertical with its length-wise axis, and the intensity that magnetizes is all identical, by every permanent magnet be separated by 30 degree angles along a radius enough large circumference be arranged in order, and the geometric center of every permanent magnet at grade, and the remanent magnetism magnetic direction of every permanent magnet rotates orientation successively according to 60 degree phase differential, due to the mutual stack of single magnets magnetic fields, will be in permanent magnet array inside, near its geometric center plane, produce the uniform magnetic field perpendicular to array axis direction, and in array region in addition, comprise the above and below of array, magnetic field intensity is almost nil, reached the magnetic resonance of the Ageing of Insulators degree detect time to the inhomogeneity requirement of main field, the surrounding magnetic field of main magnet is almost nil simultaneously.
The invention has the beneficial effects as follows, detecting magnet used with other the Ageing of Insulators degree magnetic resonance compares, the magnetic field intensity space distribution of array magnet structure is more even, the stray magnetic field of magnet outside is very faint simultaneously, and for the ease of the loading of tested insulator, cubic type magnet array can be divided into two parts and can realize machinery folding.
In the embodiment shown in fig. 1, magnet array is made up of along a circumferential arrangement 12 submodules 1, centered by the round dot of described circumference, between each submodule 1 center and circumference round dot, the angle of line is 30 degree, if take the magnetization intensity vector of the top submodule 1 as benchmark, in counter clockwise direction, the direction of each submodule 1 magnetization intensity vector is rotated 60 degree successively.In Fig. 2, show the magnetization intensity vector direction of single submodule 1.
When actual detection, first plane magnetic test coil 15 levels are put into circular ring type magnet, then by tested insulator sample 17 near magnetic test coil and be placed on its top position, by testing circuit move a spin-echo sequence and pass to shown in magnetic test coil, sample 17 is excited, later the induced magnetism resonance signal producing after testing coil 15,1/4 wavelength line 4 is transferred to the prime amplifier part 5 of testing circuit, carry out successively follow-up signal processing, finally on computing machine 14, process related data display measurement result.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, obviously, those skilled in the art can carry out various changes and modification and not depart from the spirit and scope of the present invention the present invention.Like this, if within of the present invention these are changed and modification belongs to the scope of the claims in the present invention and equivalent technologies thereof, the present invention is also intended to comprise these changes and modification interior.
Claims (2)
1. an insulator sample Degree of Ageing pick-up unit, comprise detected insulator sample (17), magnetic test coil (15) and 12 magnetizing directions and all identical cube shaped magnet submodules (1) of intensity that magnetize, it is characterized in that, 12 identical cube shaped magnet submodules (1) of volume are to wait radian compartment of terrain to be distributed on same circumference, if choose the magnetizing direction (X) of one of them cube shaped magnet submodule (1) as benchmark, on this same circumference, the magnetizing direction of the each cube shaped magnet submodule of arranging successively is along clockwise direction to rotate successively along clockwise direction 60 degree, on the home position of this uniform same circumference place circle of 12 cube shaped magnet submodules (1), be provided with magnetic test coil (15), on the central shaft of magnetic test coil (15), be provided with detected insulator sample (17), one end ground connection of magnetic test coil (15), the other end of magnetic test coil (15) is connected with one end of impedance matching electric capacity (16), be parallel with frequency tuning electric capacity (3) at the two ends of magnetic test coil (15), one end and series diode that the other end of impedance matching electric capacity (16) is 1/4 wavelength lossless line (4) with length are respectively connected one end of pipe (7), length is that the other end of 1/4 wavelength lossless line (4) is connected one end of pipe (6) with input end and the parallel diode of prime amplifier (5) respectively, the other end ground connection of parallel diode to pipe (6), the output terminal of prime amplifier (5) is connected with one end of gate controlled switch (10), the other end of gate controlled switch (10) is connected with the first input end of frequency mixer (11), the output terminal of frequency mixer (11) is connected with the input end of analog to digital converter (12), the output terminal of analog to digital converter (12) is connected with the input end of computing machine (14), the output terminal of computing machine (14) is connected with the input end of radio-frequency signal source (13), the output terminal of radio-frequency signal source (13) is connected with the second input end of frequency mixer (11) and the input end of sampling switch (9) respectively, the output terminal of sampling switch (9) is connected with the input end of power amplifier (8), the output terminal of power amplifier (8) is connected the other end of pipe (7) with series diode.
2. a kind of insulator sample Degree of Ageing pick-up unit according to claim 1, is characterized in that, described detected insulator sample (17) is torus shape, detected insulator sample (17) be arranged on magnetic test coil (15) directly over.
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103558518A (en) * | 2013-11-02 | 2014-02-05 | 国家电网公司 | Insulator sample aging degree detection device |
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Publication number | Priority date | Publication date | Assignee | Title |
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CN103558518A (en) * | 2013-11-02 | 2014-02-05 | 国家电网公司 | Insulator sample aging degree detection device |
CN103558518B (en) * | 2013-11-02 | 2015-11-25 | 国家电网公司 | The sample aging degree pick-up unit of insulator |
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