A basin type insulator detection method and a detection system

Abstract

The application discloses a kind of basin type insulator detection method and detection system, it is related to nondestructive testing technical field, and detection method includes generating test laser;Splitting test laser, generate multiple beams of to-be-focused laser;Respectively couple to-be-focused laser to multiple optical fibers transmission;In the export end of each optical fiber, respectively focus the to-be-focused laser transmission of each other, generate multiple beams of primary focused laser;The export end of each optical fiber is set to spherical surface distribution, so that multiple beams of primary focused laser self-focusing generates secondary focused laser;Using secondary focused laser detects basin type insulator.Detection system includes laser control system, laser excitation system, photoelectric detector, laser ultrasonic enhancement medium, ultrasonic wave receiving system and signal detection processing system, wherein laser excitation system includes laser excitation source, laser beam splitter, laser coupler, multiple transmission optical fibers and multiple sets of self-focusing lenses.The application can controllably adjust laser energy, focusing mode and scanning area, and improves detection sensitivity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nondestructive testing, in particular to a basin-type insulator detection method and a detection system. BACKGROUND

[0002] Nondestructive testing is a detection method for detecting the material, parts and structure of a detection object to determine the reliability, integrity, continuity and other physical properties of the detection object, under the premise of ensuring that the use performance of the detection object is not damaged, by using the changes in the reaction of heat, sound, light, electricity and magnetism caused by the existence of internal structure abnormalities or defects.

[0003] In the prior art, reference can be made to Chinese patent application for invention with publication number "CN111426919A", which discloses a basin-type insulator detection device based on laser-induced ultrasound, comprising a laser control system, a laser excitation system, a photodetector, a laser-ultrasound enhancement medium, an ultrasonic wave receiving system and a signal detection and processing system. The laser control system is connected to the laser excitation system. The pulsed laser emitted by the laser excitation system is focused on the basin-type insulator to be detected. The basin-type insulator to be detected generates ultrasonic wave signals by coating the laser-ultrasound enhancement medium. The basin-type insulator to be detected is air-coupled with the air-coupled ultrasonic transducer of the ultrasonic wave receiving system. The ultrasonic wave receiving system receives the ultrasonic wave signals and processes the ultrasonic wave signals through the signal detection and processing system. The photodetector is placed at the edge of the laser incidence path and is connected to the signal detection and processing system to provide a synchronous trigger signal for the detection signal processing system.

[0004] The basin-type insulator detection device based on laser-induced ultrasound in the prior art can complete the laser-induced ultrasound nondestructive testing of the basin-type insulator. However, the laser excitation system thereof focuses the collimated parallel laser straight light on the lens to focus the laser. The focusing mode is simple, the test laser energy is not easy to control, and the sensitivity of the detection device is affected. SUMMARY

[0005] Therefore, the technical problem to be solved by the present application is to overcome the problems of the prior art, such as the simple laser focusing mode of the basin-type insulator detection system based on laser-induced ultrasound, the difficulty in controlling the test laser energy, and the influence on the sensitivity of the detection device. The present application aims to provide a basin-type insulator detection method and a detection system to controllably adjust the energy of the finally focused laser and improve the sensitivity of the detection system.

[0006] The first aspect, to solve the above technical problems, the present application provides a basin type insulator detection method, comprising the following steps:

[0007] Generating a test laser;

[0008] Splitting the test laser to generate a plurality of beams of to-be-focused laser;

[0009] Coupling the plurality of beams of to-be-focused laser into corresponding transmission in a plurality of optical fibers respectively;

[0010] Focusing the to-be-focused laser transmitted by each optical fiber at the outlet end of the optical fiber respectively to generate a plurality of beams of primary focused laser;

[0011] The outlet end of each optical fiber is arranged in a spherical distribution, so that the plurality of beams of primary focused laser is self-focused to the position of the spherical center to generate secondary focused laser;

[0012] Using the secondary focused laser to detect the basin type insulator.

[0013] In an embodiment of the present application, after splitting the test laser, one of the beams of to-be-focused laser is marked as a trigger beam, and the trigger beam is used to trigger the start of the signal detection system; the other to-be-focused laser is coupled into the corresponding optical fiber for transmission.

[0014] In an embodiment of the present application, further comprising: coating a laser-ultrasound enhancement medium on the basin type insulator to be detected, so that the gathering point of the secondary focused laser acts on the laser-ultrasound enhancement medium to generate an ultrasonic signal.

[0015] In an embodiment of the present application, further comprising: coating a laser-ultrasound enhancement medium on the outlet end of the optical fiber, so that the focus point of the primary focused laser acts on the laser-ultrasound enhancement medium to generate a plurality of laser-ultrasound single elements, and the plurality of laser-ultrasound single elements are arranged in a spherical distribution, and the plurality of laser-ultrasound single elements act on the basin type insulator to be detected after self-focusing.

[0016] In an embodiment of the present application, the position of the outlet end of the optical fiber is adjusted to change the curvature radius of the spherical distribution of the arrangement of the plurality of laser-ultrasound single elements, so that each laser-ultrasound single element acts on the basin type insulator to be detected multiple times at different deflection angles to irradiate any position of the basin type insulator to be detected.

[0017] In an embodiment of the present application, the echo signal after the laser-ultrasound single element acts on the basin type insulator to be detected is received and processed, and the echo signals under a plurality of different deflection angles are coherently superimposed to generate an ultrasonic detection image.

[0018] In a second aspect, to solve the above technical problems, the application further provides a pot insulator detection system, comprising a laser control system, a laser excitation system, a photoelectric detector, a laser ultrasonic enhancement medium, an ultrasonic wave receiving system and a signal detection and processing system, wherein the laser excitation system comprises:

[0019] a laser excitation source connected with the laser control system;

[0020] a laser beam splitter connected with the laser excitation source;

[0021] a laser coupler connected with the laser beam splitter;

[0022] a plurality of transmission optical fibers respectively connected with the laser coupler;

[0023] a plurality of groups of self-focusing lenses connected with outlet ends of the plurality of transmission optical fibers, and the plurality of groups of self-focusing lenses are arranged in a spherical distribution;

[0024] wherein the laser control system controls the laser excitation source to generate test laser, the laser beam splitter splits the test laser into a plurality of beams of to-be-focused laser, the laser coupler correspondingly couples the to-be-focused laser into the plurality of transmission optical fibers, the self-focusing lenses generate the to-be-focused laser output by the transmission optical fibers into primary focused laser, and the primary focused laser generates secondary focused laser after being emitted.

[0025] In an embodiment of the application, the laser excitation source is a Q-switched laser.

[0026] In an embodiment of the application, the photoelectric detector is located on an exit light path of one of the beams of to-be-focused laser, the photoelectric detector is connected with the signal detection and processing system, and the signal detection and processing system is further connected with the ultrasonic wave receiving system.

[0027] In an embodiment of the application, the ultrasonic wave receiving system comprises an air-coupled ultrasonic probe or a laser Doppler vibrometer.

[0028] The above technical solution of the application has the following advantages compared with the prior art:

[0029] The pot-type insulator detection method and detection system, by splitting the test laser, coupling the split multiple beams of focused laser into multiple optical fibers respectively, generating multiple primary focused lasers by first focusing at the outlet end of the optical fiber, and generating secondary focused lasers by second focusing of the multiple primary focused lasers, the focusing of the test laser is realized; after twice coupling and focusing, the energy intensity of the final focusing point of the test laser is effectively ensured, and by controlling the focusing number and focusing mode of the multiple primary focused lasers, the final focused laser energy can be effectively controlled and adjusted, and the sensitivity of the detection system is improved. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to make the content of the present application more easily understood, the present application will be further described in detail below according to specific embodiments of the present application and in conjunction with the drawings, in which

[0031] Figure 1 is a structure schematic diagram of the pot-type insulator detection system in the preferred embodiment of the present application;

[0032] Figure 2 is Figure 1 a structure schematic diagram of the laser excitation system in the pot-type insulator detection system shown.

[0033] Description of the drawings: 1, laser control system; 2, laser excitation system; 21, laser excitation source; 22, laser beam splitter; 23, laser coupler; 24, transmission optical fiber; 25, self-focusing lens; 3, photoelectric detector; 4, laser ultrasonic enhancement medium; 5, ultrasonic wave receiving system; 6, signal detection and processing system. DETAILED DESCRIPTION

[0034] The present application will be further described below in conjunction with the drawings and specific embodiments, so that those skilled in the art can better understand the present application and implement it, but the embodiments are not as a limitation on the present application.

[0035] Example 1

[0036] The present application discloses a pot-type insulator detection method, comprising the following steps:

[0037] Generating a test laser by excitation;

[0038] Splitting the test laser to generate multiple beams of focused laser;

[0039] Coupling the multiple beams of focused laser into multiple optical fibers respectively for corresponding transmission;

[0040] Focusing the focused laser transmitted by each optical fiber at the outlet end of the optical fiber respectively to generate multiple primary focused lasers;

[0041] The outlet ends of the optical fibers are arranged in a spherical surface distribution, so that the multiple primary focused lasers are self-focused to a spherical center position to generate secondary focused lasers;

[0042] The secondary focused lasers are used to detect the basin-type insulator.

[0043] The basin-type insulator detection method is coupled twice, effectively ensuring the energy intensity of the final focused laser, and through controlling the focusing number and focusing mode of the multiple primary focused lasers, the final focused laser energy can be effectively controlled and adjusted, and the sensitivity of the detection system is improved.

[0044] In the embodiment, specifically, the test laser can be split into 8, 16 or 32 paths of focused lasers, so as to ensure the sensitivity of the controllable adjustment and improve the control refinement.

[0045] In the embodiment, preferably, after the test laser is split, one of the focused lasers is marked as a trigger beam, and the trigger beam is used to trigger the signal detection system to start; and the other focused lasers are coupled into the corresponding optical fibers for transmission.

[0046] Taking one of the focused lasers as a trigger beam, since the trigger beam and the remaining focused lasers are generated at the same time, the synchronization and accuracy of the signal detection system starting are effectively improved, so as to ensure the reliability of the detection result.

[0047] In the embodiment, specifically, the focused laser is incident on the laser-ultrasonic enhancement medium to induce ultrasonic waves, wherein the laser-ultrasonic enhancement medium is an elastic material, and the ultrasonic waves are generated through the thermoelastic effect after the laser is incident. The ultrasonic waves propagate in the basin-type insulator to be detected, and when the basin-type insulator to be detected contains defects such as cracks, bubbles and impurities, the acoustic impedance changes, and the sound wave propagation process will reflect, refract and the like. By comparing the echo signals of the sound waves with and without defects, the defect position, size and shape of the basin-type insulator to be detected can be obtained, so as to realize the laser-ultrasonic nondestructive testing of the basin-type insulator to be detected.

[0048] In the embodiment, preferably, the following two coating methods of the laser-ultrasonic enhancement medium are provided:

[0049] A, specifically, the laser-ultrasonic enhancement medium is coated on the basin-type insulator to be detected, so that the gathering point of the secondary focused laser acts on the laser-ultrasonic enhancement medium to generate ultrasonic signals.

[0050] By coating the laser-ultrasonic enhancement medium on the basin-type insulator to be detected, the secondary focused laser after twice focusing provides high-power and high-intensity incident laser, so as to generate high-amplitude and high-frequency ultrasonic waves in the basin-type insulator to be detected, and the clarity quality of the detection result is improved.

[0051] B, specifically, the laser-ultrasonic enhancement medium is coated to the outlet end of the optical fiber, the focal point of the primary focused laser acts on the laser-ultrasonic enhancement medium to generate a plurality of laser-ultrasonic single elements, the plurality of laser-ultrasonic single elements are arranged in a spherical distribution, and the plurality of laser-ultrasonic single elements act on the to-be-detected pot-type insulator after being focused.

[0052] The laser-ultrasonic enhancement medium is coated to the outlet end of the plurality of optical fibers, so that each primary focused laser generates a laser-ultrasonic single element after being focused, and the plurality of laser-ultrasonic single elements are focused and generated along the generation path of the secondary focused laser to generate a focused laser-ultrasonic source, thereby acting on the to-be-detected pot-type insulator for detection, and the richness of the ultrasonic wave mode is ensured.

[0053] In the embodiment, preferably, the position of the outlet end of the optical fiber is adjusted to change the curvature radius of the spherical distribution of the plurality of laser-ultrasonic single elements, so that each laser-ultrasonic single element acts on the to-be-detected pot-type insulator multiple times at different deflection angles to irradiate any position of the to-be-detected pot-type insulator.

[0054] By arranging the laser-ultrasonic single elements, the focused scanning area of the ultrasonic wave is effectively improved, and the plurality of laser-ultrasonic single elements are arranged on spherical surfaces with different curvature radii, so that the incidence angle of the laser-ultrasonic single elements is changed, thereby enabling scanning and detection of any position and any area of the to-be-detected pot-type insulator to obtain detection echoes at multiple angles.

[0055] In the embodiment, preferably, the echo signal after the laser-ultrasonic single element acts on the to-be-detected pot-type insulator is received and processed, the echo signals at multiple different deflection angles are coherently superimposed to generate an ultrasonic wave detection image.

[0056] The scanning mode of the plurality of laser-ultrasonic single elements is a plane wave excitation mode, the echo signals at multiple different deflection angles are coherently superimposed, and the same defect can be accurately verified and positioned by different echo signals at different deflection angles, thereby improving the quality of the ultrasonic wave detection image.

[0057] Embodiment two

[0058] Referring to Figure 1 and Figure 2 It is shown that the application also discloses a pot-type insulator detection system, which comprises a laser control system 1, a laser excitation system 2, a photoelectric detector 3, a laser-ultrasonic enhancement medium 4, an ultrasonic wave receiving system 5, and a signal detection and processing system 6, and the laser excitation system 2 comprises:

[0059] a laser excitation source 21, the laser excitation source 21 is connected with the laser control system 1;

[0060] A laser beam splitter 22 is connected with the laser excitation source 21.

[0061] A laser coupler 23 is connected with the laser beam splitter 22.

[0062] A plurality of transmission optical fibers 24 are respectively connected with the laser coupler 23.

[0063] A plurality of self-focusing lenses 25 are connected with outlet ends of the plurality of transmission optical fibers 24, and the plurality of self-focusing lenses 25 are arranged in a spherical distribution.

[0064] The laser control system 1 controls the laser excitation source 21 to generate test laser, the laser beam splitter 22 splits the test laser into a plurality of to-be-focused laser beams, the laser coupler 23 correspondingly couples the to-be-focused laser beams into the plurality of transmission optical fibers 24, and the self-focusing lenses 25 generate primary focused laser beams from the to-be-focused laser beams output by the transmission optical fibers 24, and the primary focused laser beams generate secondary focused laser beams after being emitted.

[0065] The laser excitation system effectively realizes twice focusing of the test laser, guarantees the energy and controllability of the focused laser, and improves the detection operation sensitivity of the detection system.

[0066] In the embodiment, preferably, the laser excitation source 21 is a Q-switched laser.

[0067] Specifically, the laser control system 1 sets voltage waveform parameters, realizes excitation of the Q-switched laser by using an external triggering mode, determines the energy and pulse width of the excited laser, and makes the energy and pulse width less than a damage threshold of the laser-ultrasound enhancement medium 4, so as to guarantee the reliability of the test.

[0068] In the embodiment, preferably, the laser-ultrasound enhancement medium 4 can be coated on the to-be-detected pot-type insulator to generate secondary focused laser-induced ultrasonic waves, or can be coated on the plurality of self-focusing lenses 25 to generate a plurality of laser-ultrasound single elements.

[0069] In the embodiment, preferably, the photodetector 3 is located on an exit light path of one of the to-be-focused laser beams, the photodetector 3 is connected with the signal detection and processing system 6, and the signal detection and processing system 6 is further connected with the ultrasonic wave receiving system 5.

[0070] In the embodiment, preferably, the ultrasonic wave receiving system 5 includes an air-coupled ultrasonic probe or a laser Doppler vibrometer.

[0071] The implementation principle of the embodiment is that: the basin type insulator detection system generates test laser by controlling laser excitation source 21 to generate test laser, and the test laser generates multiple beams of to-be-focused laser after being split by laser beam splitter 22. One of the multiple beams of to-be-focused laser is received by photoelectric detector 3 as a trigger signal, and the other to-be-focused laser is coupled into transmission optical fiber 24 through laser coupler 23. After the to-be-focused laser passes through self-focusing lens 25, multiple beams of primary focused laser are generated, and the primary focused laser generates secondary focused laser in a spherical distribution arrangement. Corresponding to two coating modes of laser ultrasound enhancement medium 4, the primary focused laser or the secondary focused laser acts on the laser ultrasound enhancement medium 4 to induce the generation of ultrasonic waves propagating in the basin type insulator to be detected. Ultrasonic wave receiving system 5 receives the echo signal of the ultrasonic wave propagation, and signal detection processing system 6 is connected with photoelectric detector 3 and ultrasonic wave receiving system 5 to analyze and process the received echo signal, and finally obtain the basin type insulator ultrasonic detection image.

[0072] Obviously, the above embodiment is only an example for clearly illustrating, and is not limited to the implementation. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, all the implementation is not required and cannot be exhausted. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A method for detecting a pot-type insulator, characterized in that: The following steps are involved: Stimulates generation of test laser light; Splitting the test laser to generate multiple beams of laser light to be focused; Respectively coupling the multiple beams of laser light to be focused into multiple optical fibers for corresponding transmission; Focusing the laser beams to be focused at the outlet ends of the optical fibers to generate multiple beams of once-focused laser beams; The outlet end of each optical fiber is arranged to be spherically distributed, so that the multiple beams of the primary focused laser light are self-focused to the center of the sphere to generate secondary focused laser light; Using the secondary focused laser to detect pot insulators; A laser ultrasonic enhancement medium is applied to the outlet end of the optical fiber, so that the focal point of the once-focused laser acts on the laser ultrasonic enhancement medium to generate a plurality of laser ultrasonic single array elements. The plurality of laser ultrasonic single array elements are arranged in a spherical distribution. The plurality of laser ultrasonic single array elements act on the pot-type insulator to be inspected after self-focusing. The outlet end position of the optical fiber is adjusted to change the curvature radius of the sphere on which the plurality of laser ultrasonic single array elements are arranged and distributed, so that each laser ultrasonic single array element acts on the pot-type insulator to be inspected multiple times at different deflection angles, irradiating any position of the pot-type insulator to be inspected.

2. The pot-type insulator detection method according to claim 1, characterized in that: After the test laser is split, one of the laser beams to be focused is marked as a trigger beam, which is used to trigger the start of the signal detection system; the other laser beams to be focused are coupled to the corresponding optical fiber for transmission.

3. The pot insulator detection method according to claim 1, characterized in that: Also includes: A laser ultrasonic enhancement medium is coated on the pot-type insulator to be inspected, and the focal point of the secondary focused laser acts on the laser ultrasonic enhancement medium to generate an ultrasonic signal.

4. The pot-type insulator detection method according to claim 1, characterized in that: The echo signal after the laser ultrasonic single array element acts on the pot-type insulator to be detected is received and processed, and the echo signals at multiple different deflection angles are coherently superimposed to generate an ultrasonic detection image.

5. A pot-type insulator detection system, characterized by: It includes a laser control system, a laser excitation system, a photoelectric detector, a laser ultrasonic enhancement medium, an ultrasonic receiving system and a signal detection and processing system. The laser excitation system includes: A laser excitation source, the laser excitation source being connected to the laser control system; a laser beam splitter connected to the laser excitation source; a laser coupler connected to the laser beam splitter; a plurality of transmission optical fibers, each of which is connected to the laser coupler; Multiple groups of self-focusing lenses, the multiple groups of self-focusing lenses are connected to the outlet ends of the multiple transmission optical fibers, and the multiple groups of self-focusing lenses are arranged in a spherical distribution; The laser control system controls the laser excitation source to generate a test laser, the laser beam splitter splits the test laser into multiple beams of laser light to be focused, the laser coupler couples the laser light to be focused into multiple transmission optical fibers, the self-focusing lens generates the laser light to be focused outputted from the transmission optical fiber into a primary focused laser, the primary focused laser light self-focuses to generate a secondary focused laser light after being emitted, a laser ultrasonic enhancement medium is coated on the outlet end of the optical fiber, so that the focal point of the primary focused laser light acts on the laser ultrasonic enhancement medium to generate multiple laser ultrasonic single array elements, the multiple laser ultrasonic single array elements are arranged in a spherical distribution, the multiple laser ultrasonic single array elements act on the pot-type insulator to be inspected after self-focusing, the outlet end position of the optical fiber is adjusted to change the curvature radius of the sphere on which the multiple laser ultrasonic single array elements are arranged and distributed, so that each laser ultrasonic single array element acts on the pot-type insulator to be inspected multiple times at different deflection angles, irradiating any position of the pot-type insulator to be inspected.

6. The pot insulator detection system according to claim 5, characterized in that: The laser excitation source is a Q-switched laser.

7. The pot insulator detection system according to claim 5, characterized in that: The photoelectric detector is located on the outgoing optical path of one of the laser beams to be focused. The photoelectric detector is connected to the signal detection and processing system, and the signal detection and processing system is also connected to the ultrasonic receiving system.

8. The pot insulator detection system according to claim 5, characterized in that: The ultrasonic receiving system includes an air-coupled ultrasonic probe or a laser Doppler vibrometer.

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