An infrared spectrum detection system and judgment method for insulator aging degree in situ

Abstract

The present invention provides an infrared spectrum detection system for in-situ insulator aging degree and a judgment method thereof. The system includes an unmanned aerial vehicle, an infrared spectrum detection device, a mechanical arm and a wireless control module. The wireless control module controls the mechanical arm to bring the infrared spectrum detection device close to the insulator to be detected. The wireless control module can receive the infrared spectrum data detected by the infrared spectrum detection device and transmit it to the control terminal that is transmitted to the ground. With the assistance of the work of the unmanned aerial vehicle and the mechanical arm, it is only necessary to approach the insulator to be detected to obtain the corresponding data and judge whether there is aging phenomenon, which solves the problem that the insulator needs to be removed in the current technology in order to collect data to judge aging. The present invention can perform online detection of insulators in the air without stopping the work of the transmission line or removing the insulator.

Description

Technical Field

[0001] The present invention relates to the technical field of power transmission line maintenance equipment, and more specifically to an infrared spectrum detection system for insulator aging degree in situ and a judgment method thereof. Background Art

[0002] Insulators are important components in high-voltage transmission lines. After long-term use, insulators will age, and aged insulators will affect the normal operation of high-voltage transmission lines. However, due to the particularity of high-voltage transmission lines, we cannot frequently stop power transmission and remove insulators for inspection. Therefore, in-situ insulator detection research is very necessary.

[0003] A Chinese patent discloses an unmanned aerial vehicle zero detection device for porcelain insulators on ultra-ultra-high voltage transmission lines (patent number: 2021222121899). It uses an unmanned aerial vehicle equipped with an insulator detector to collect the electric field distribution around the tension porcelain insulator, and compares and analyzes the data obtained from the detection to determine whether there are degraded or zero-value insulators in the insulator string, replacing manual insulator detection operations. Through real-time monitoring of the gimbal camera and flexible adjustment of the robotic arm assembly, the detection needle can accurately enter between the insulation to be detected, which not only reduces the labor intensity of the workers and the difficulty of operation, but also greatly improves the efficiency and quality of the detection operation, avoiding the impact on the personal safety of the operator. A rotor protection device is also installed on the upper part of the drone. The setting of the rotor protection device can ensure that the drone avoids the influence of the transmission line on the rotor during the ascent, and then smoothly moves the detection needle to the position of the insulator string that needs to be detected, so as to facilitate the subsequent zero detection of the insulator string. However, when this patent is used in practice, its detection needle needs to enter the two sides of the insulator pieces on the adjacent sides to read the resistance of the insulator. The zero detection operation of the above two insulator pieces is a process step. Therefore, it takes a lot of time to ensure that the detection needle is inserted between the insulators. The operation is relatively cumbersome. In addition, its detection method for insulators is to use an insulator detector to collect the electric field distribution around the tension porcelain insulator, and compare and analyze the data obtained from the detection to determine whether there are degraded or zero-value insulators in the insulator string. The technical solution of this patent is to perform zero-value detection on ceramic insulators, which is not suitable for detecting composite insulators.

[0004] In summary, in the art, a detection device with higher efficiency, more accurate detection and more convenient detection can be replaced to detect composite insulators or ceramic insulators. Summary of the invention

[0005] The main purpose of the present invention is to provide an in-situ infrared spectrum detection system for the aging degree of insulators. By using the system and method, infrared spectrum detection of insulators can be performed without stopping the operation of high-voltage transmission lines and removing insulators.

[0006] Another object of the present invention is to solve the problem in the current technology that the probe needs to enter both sides of the insulator pieces on the adjacent sides to collect data for aging judgment, and to provide an in-situ insulator aging degree infrared spectrum detection system that can achieve detection only by approaching the insulator.

[0007] The technical solution of the present invention is: an in-situ infrared spectrum detection system for the aging degree of insulators, comprising an unmanned aerial vehicle, an infrared spectrum detection device, a mechanical arm and a wireless control module, the head end of the mechanical arm is fixed at the bottom end of the unmanned aerial vehicle, the wireless control module is fixed at the top of the unmanned aerial vehicle, the infrared light detection device is installed at the end of the mechanical arm, the wireless control module is used to control the opening and closing of the infrared spectrum detection device and the mechanical arm, and the wireless control module controls the mechanical arm to bring the infrared spectrum detection device close to the insulator to be detected, and the wireless control module can receive the infrared spectrum data detected by the infrared spectrum detection device and transmit it to the control end for transmission to the ground.

[0008] An infrared spectrum judgment method for the aging degree of an insulator in situ includes the following steps: step 1, performing spectrum data detection on a standard sample by an infrared spectrum detection device, and performing infrared spectrum detection on a standard new insulator sample before a drone inspection to obtain a reflection spectrum array sa1, and taking sa1 as standard spectrum data;

[0009] Step 2: Use an infrared spectrum detection device to detect the emission spectrum array sa2 of the insulator to be detected in real time, and then detect the reflection spectrum array sa3 of the insulator to be detected in situ;

[0010] Step 3, using the formula (sa3-sa2) / sa1, obtain the ratio (sa3-sa2) / sa1 between the infrared spectra of the outdoor insulator and the standard insulator, which is defined as the detection spectrum s1;

[0011] Step 4, performing Fourier transform FFT (s1) on s1 in step 3, and then intercepting the signal with an absolute value of frequency less than 1 Hz from FFT (s1) to remove the DC background and DC noise signals inside the instrument, and then performing inverse Fourier transform to obtain a spectrum signal s2 without the influence of the DC background and DC noise signals;

[0012] Step 5: low-pass filter s2 in step 4 with a cutoff frequency of K Hz to remove the high-frequency components of the signal and the white noise signal caused by the change of outdoor ambient temperature, and then perform inverse Fourier transform to obtain the spectrum signal s3 affected by the white noise;

[0013] Step 6: Perform PCA decomposition on s3 in step 5 to decompose the signal into multiple independent characteristic signals, take the characteristic signal corresponding to the maximum eigenvalue for Fourier transform, and find the maximum peak in the spectrum as the judgment threshold T;

[0014] Step seven, extracting the reflection spectrum value a1 of the band w1 corresponding to the Si-O-Si bond and the reflection spectrum value a2 of the band w2 corresponding to the Si-CH3 bond from the standard spectrum data sa1 in step one, extracting the emission spectrum value a3 of the band w1 and the emission spectrum value a4 of the band w2 from the emission spectrum array sa2 in step two, extracting the reflection spectrum value a5 of the band w1 corresponding to the Si-O-Si bond and the reflection spectrum value a6 of the band w2 corresponding to the Si-CH3 bond from the reflection spectrum array sa3 in step two, the in-situ reflection spectrum value of the Si-O-Si bond is a5-a3, and the in-situ reflection spectrum value of the Si-CH3 bond is a6-a4, which is conducive to judging the aging degree of the insulator by the ratio of (a5-a3) / a1 and (a6-a4) / a2. When (a5-a3) / a1 or (a6-a4) / a2 is less than the threshold value T, it is considered that the insulator has aged.

[0015] The beneficial effects of the present invention are as follows: through the system and method of the present invention, with the assistance of a drone, the infrared light source can be transmitted to the insulator that needs to be inspected on the transmission line through a mechanical arm that clamps the infrared fiber optic probe, and the infrared spectrum reflected by the insulator that needs to be inspected is further returned to its infrared spectrometer through the infrared fiber optic probe. With the assistance of the work of the drone and the mechanical arm, it is only necessary to approach the insulator that needs to be inspected to obtain the corresponding data and determine whether there is aging, thereby solving the problem of the current technology that the insulator needs to be removed before data can be collected to determine aging. The present invention can perform online detection of insulators in the air without stopping the transmission line or removing the insulator. The infrared spectrum judgment method for the degree of aging of the present invention has higher judgment efficiency and more accurate judgment than the current technology, providing technical personnel in the field with a judgment method different from the current technology, thereby increasing the choice space for technical personnel in the field. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the present invention approaching an insulator during specific use.

[0017] Figure 2 It is a schematic structural diagram of the infrared spectrum detection device of the present invention.

[0018] Figure 3 It is a schematic structural diagram of the mechanical arm of the present invention. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0020] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0021] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0023] Please also read Figures 1 to 3 The present invention now provides an in-situ infrared spectrum detection system for the aging degree of insulators, which includes an unmanned aerial vehicle 10, an infrared spectrum detection device 20, a mechanical arm 30 and a wireless control module 40. The head end of the mechanical arm 30 is fixed to the bottom end of the unmanned aerial vehicle 10, the wireless control module 30 is fixed to the top of the unmanned aerial vehicle 10, the infrared light detection device 20 is installed at the end of the mechanical arm 30, and the wireless control module 40 is used to control the opening and closing of the infrared spectrum detection device 20 and the mechanical arm 30. The wireless control module 40 controls the mechanical arm 30 to bring the infrared spectrum detection device 20 close to the insulator to be detected. The wireless control module 40 can receive the infrared spectrum data detected by the infrared spectrum detection device 20 and transmit it to the control end transmitted to the ground (the control end is not shown in the figure, and the control end is used to control the flight of the unmanned aerial vehicle, wirelessly connect with the wireless control module, and calculate relevant values).

[0024] The control end calculates the received infrared spectrum data to obtain a first comparison value, a second comparison value and a threshold value F. When the first comparison value or the second comparison value is less than the threshold value F, it is determined that the detected insulator is aged.

[0025] The aging degree of the insulator to be detected is determined by adaptively extracting a threshold value based on the infrared spectrum absorption peak value, and combining the Si-O-Si bond and Si-CH3 bond absorption peak values ​​to determine the aging degree of the insulator to be detected.

[0026] The infrared spectrum detection device can detect the emission spectrum array sa2 of the insulator to be detected and the reflection spectrum array sa3 of the insulator to be detected, and the infrared spectrum data includes the emission spectrum array sa2 of the insulator to be detected and the reflection spectrum array sa3 of the insulator to be detected.

[0027] The infrared spectrum detection device 20 includes an infrared spectrometer 21, an infrared light source 22 and an infrared fiber optic probe 23. The infrared fiber optic probe 23 is connected to the infrared light source 22 and the infrared spectrometer 21 through cables, respectively. The infrared spectrometer 21 and the infrared light source 22 can be fixed on the drone 10 or the mechanical arm 30. The infrared fiber optic probe 23 is arranged at the end of the mechanical arm 30. The front end of the infrared fiber optic probe 23 is clamped by the mechanical arm and approaches the insulator to be detected. The infrared light emitted by the infrared light source 22 is emitted through the front end of the infrared fiber optic probe and irradiates the insulator to be detected. The infrared light reflected by the insulator to be detected enters the infrared fiber optic probe again and is transmitted backward to the infrared spectrometer 21. The infrared spectrometer 21 obtains infrared spectrum data and transmits it to the wireless control module, and transmits the data to the ground control end through the wireless control module 40.

[0028] The mechanical arm 30 includes a top servo 31 fixed to the drone 10 and a plurality of joint servos 32. The top servo 31 is movably connected to one of the joint servos 32 through a connecting frame 311 and a flange 312, and the remaining joint servos are movably connected in sequence through the connecting frame 311 and the flange 312. By driving the servo, a certain angle difference is formed between the front and rear structures of the servo connection, thereby realizing the movement of the mechanical arm in space, so that the end joint servo can maintain different postures in space, driving the infrared fiber optic probe 23 located at the front end to scan and detect the detection target (insulator to be detected) in the required posture. The maximum rotation angle of the top servo 31 or the joint servo 32 is 60° to ensure that the mechanical arm 30 does not touch other parts of the drone, prevent misoperation from damaging the chassis or other parts of the drone, and increase safety performance.

[0029] The infrared fiber optic probe 23 is fixed on the joint servo 32 at the end of the robotic arm 30. Two cameras 24 are symmetrically fixed on the outer side of the infrared fiber optic probe 23. When the robotic arm 30 approaches the insulator to be inspected for observation, the camera obtains the image and transmits it to the ground control end through the wireless control module. The computer at the ground control end uses the parallax algorithm to obtain the distance between the insulator to be inspected and the robotic arm, and assists the ground staff to control the robotic arm to avoid the infrared fiber optic probe from colliding with the insulator when approaching the insulator.

[0030] An infrared spectrum judgment method for insulator aging degree in situ, comprising the following steps:

[0031] Step 1: Use an infrared spectrum detection device to detect the spectrum data of the standard sample. Before the drone inspection, perform infrared spectrum detection on the standard new insulator sample to obtain the reflection spectrum array sa1, and use sa1 as the standard spectrum data;

[0032] Step 2: Use an infrared spectrum detection device to detect the emission spectrum array sa2 of the insulator to be detected in real time, and then detect the reflection spectrum array sa3 of the insulator to be detected in situ;

[0033] Step 3, using the formula (sa3-sa2) / sa1, obtain the ratio between the infrared spectra of the outdoor insulator and the standard insulator, which is defined as the detection spectrum s1;

[0034] Step 4, performing Fourier transform FFT (s1) on s1 in step 3, and then intercepting the signal with an absolute value of frequency less than 1 Hz from FFT (s1) to remove the DC background and DC noise signals inside the instrument, and then performing inverse Fourier transform to obtain a spectrum signal s2 without the influence of the DC background and DC noise signals;

[0035] Step 5: low-pass filter s2 in step 4 with a cutoff frequency of K Hz to remove the high-frequency components of the signal and the white noise signal caused by the change of outdoor ambient temperature, and then perform inverse Fourier transform to obtain the spectrum signal s3 affected by the white noise;

[0036] Step 6: Perform PCA decomposition on s3 in step 5 to decompose the signal into multiple independent characteristic signals, take the characteristic signal corresponding to the maximum eigenvalue for Fourier transform, and find the maximum peak in the spectrum as the judgment threshold F;

[0037] Step seven, extracting the reflection spectrum value a1 of the band w1 corresponding to the Si-O-Si bond and the reflection spectrum value a2 of the band w2 corresponding to the Si-CH3 bond from the standard spectrum data sa1 in step one, extracting the emission spectrum value a3 of the band w1 and the emission spectrum value a4 of the band w2 from the emission spectrum array sa2 in step two, extracting the reflection spectrum value a5 of the band w1 corresponding to the Si-O-Si bond and the reflection spectrum value a6 of the band w2 corresponding to the Si-CH3 bond from the reflection spectrum array sa3 in step two, the in-situ reflection spectrum value of the Si-O-Si bond is a5-a3, and the in-situ reflection spectrum value of the Si-CH3 bond is a6-a4, which is conducive to judging the aging degree of the insulator by the ratio of (a5-a3) / a1 and (a6-a4) / a2. When (a5-a3) / a1 or (a6-a4) / a2 is less than the threshold value F, it is considered that the insulator has aged.

[0038] It is worth mentioning that the value obtained by (a5-a3) / a1 is the first comparison value mentioned above, and the value obtained by (a6-a4) / a2 is the second comparison value.

[0039] It is worth mentioning that (sa3-sa2) / sa1 in step three is used as a preprocessing method to eliminate the influence of the outdoor environment on the detection signal (outdoor background infrared spectrum subtraction), and by performing proportional calculation with the standard spectrum data, the ratio (sa3-sa2) / sa1 between the infrared spectra of outdoor insulators and standard insulators is obtained.

[0040] Specifically, the infrared spectrum detection device in step 1 or step 2 includes an infrared spectrometer 21, an infrared light source 22 and an infrared optical fiber probe 23, and the infrared optical fiber probe 23 is connected to the infrared light source 22 and the infrared spectrometer 21 respectively through cables.

[0041] Specifically, in step 2, the infrared light source is first turned off to detect the emission spectrum array sa2 of the insulator to be detected in real time outdoors, and then the infrared light source is turned on to detect the reflection spectrum array sa3 of the insulator to be detected in situ outdoors.

[0042] The above sa1-sa3 and s1 are all rational number arrays, and the array dimension is equal to the number of detection channels of the infrared spectrometer.

[0043] Specifically, the value of the cut-off frequency K in step 5 is related to the ambient temperature, and the specific calculation formula is K=2 / exp(T), where T is the ambient temperature value during the detection process;

[0044] The system and method of the present invention are suitable for detecting ceramic insulators or composite insulators.

[0045] Through the system and method of the present invention, with the assistance of a drone, the infrared light source can be transmitted to the insulator that needs to be detected on the transmission line through a mechanical arm that clamps the infrared fiber probe, and the infrared spectrum reflected by the insulator that needs to be detected is further returned to its infrared spectrometer through the infrared fiber probe. With the assistance of the work of the drone and the mechanical arm, it is only necessary to approach the insulator that needs to be detected to obtain the corresponding data and determine whether there is aging, thereby solving the problem that the insulator needs to be removed to collect data to determine aging in the current technology and the problem that the technical solution mentioned in the background technology is not suitable for composite insulators for zero value detection. The present invention can perform online detection of insulators in the air without stopping the work of the transmission line or removing the insulator. The infrared spectrum judgment method of the present invention has higher judgment efficiency and more accurate judgment than the current technology, providing a judgment method different from the current technology for those skilled in the art, and increasing the choice space for those skilled in the art.

[0046] The embodiment and drawings of the present invention are only for illustrating the design concept of the present invention, and the protection scope of the present invention should not be limited to this embodiment.

[0047] It can be seen from the above description that the design purpose of the present invention can be effectively implemented. The embodiment part shows the purpose of the present invention and the implementation function and structural theme, and includes other equivalent replacements.

[0048] Therefore, the rights of the present invention include other equivalent implementations, and the specific scope of rights refers to the claims.

Claims

1. A method for judging the aging degree of insulators by infrared spectrum, comprising the following steps: Step 1: Use an infrared spectrum detection device to detect the spectrum data of the standard sample. Before the drone inspection, perform infrared spectrum detection on the standard new insulator sample to obtain the reflection spectrum array sa1, and use sa1 as the standard spectrum data; Step 2: Use an infrared spectrum detection device to detect the emission spectrum array sa2 of the insulator to be detected in real time, and then detect the reflection spectrum array sa3 of the insulator to be detected in situ; Step 3, using the formula (sa3-sa2) / sa1, obtain the ratio between the infrared spectra of the outdoor insulator and the standard insulator, which is defined as the detection spectrum s1; Step 4, performing Fourier transform FFT (s1) on s1 in step 3, and then intercepting the signal with an absolute value of frequency less than 1 Hz from FFT (s1) to remove the DC background and DC noise signals inside the instrument, and then performing inverse Fourier transform to obtain a spectrum signal s2 without the influence of the DC background and DC noise signals; Step 5: low-pass filter s2 in step 4 with a cutoff frequency of K Hz to remove the high-frequency components of the signal and the white noise signal caused by the change of outdoor ambient temperature, and then perform inverse Fourier transform to obtain the spectrum signal s3 affected by the white noise; Step 6: Perform PCA decomposition on s3 in step 5 to decompose the signal into multiple independent characteristic signals, take the characteristic signal corresponding to the maximum eigenvalue for Fourier transform, and find the maximum peak in the spectrum as the judgment threshold F; Step seven, extracting the reflection spectrum value a1 of the band w1 corresponding to the Si-O-Si bond and the reflection spectrum value a2 of the band w2 corresponding to the Si-CH3 bond from the standard spectrum data sa1 in step one, extracting the emission spectrum value a3 of the band w1 and the emission spectrum value a4 of the band w2 from the emission spectrum array sa2 in step two, extracting the reflection spectrum value a5 of the band w1 corresponding to the Si-O-Si bond and the reflection spectrum value a6 of the band w2 corresponding to the Si-CH3 bond from the reflection spectrum array sa3 in step two, the in-situ reflection spectrum value of the Si-O-Si bond is a5-a3, and the in-situ reflection spectrum value of the Si-CH3 bond is a6-a4, which is conducive to judging the aging degree of the insulator by the ratio of (a5-a3) / a1 and (a6-a4) / a2. When (a5-a3) / a1 or (a6-a4) / a2 is less than the threshold value F, it is considered that the insulator has aged.

2. The infrared spectrum judgment method for in-situ insulator aging degree according to claim 1, characterized in that: The infrared spectrum detection device in step one or step two includes an infrared spectrometer, an infrared light source and an infrared optical fiber probe, and the infrared optical fiber probe is connected to the infrared light source and the infrared spectrometer respectively through cables.

3. The infrared spectrum judgment method for in-situ insulator aging degree according to claim 2, characterized in that: In the step 2, the infrared light source is first turned off to detect the emission spectrum array sa2 of the insulator to be detected in real time outdoors, and then the infrared light source is turned on to detect the reflection spectrum array sa3 of the insulator to be detected outdoors in situ.

4. The infrared spectrum judgment method for in-situ insulator aging degree according to claim 1, characterized in that: The value of the cut-off frequency K in step 5 is related to the ambient temperature, and the specific calculation formula is K=2 / exp(T), where T is the ambient temperature value during the detection process.

5. An in-situ infrared spectrum detection system for insulator aging degree, characterized by: The invention comprises an unmanned aerial vehicle, an infrared spectrum detection device, a mechanical arm and a wireless control module, wherein the head end of the mechanical arm is fixed at the bottom end of the unmanned aerial vehicle, the wireless control module is fixed at the top of the unmanned aerial vehicle, the infrared spectrum detection device is installed at the end of the mechanical arm, the wireless control module is used to control the opening and closing of the infrared spectrum detection device and the mechanical arm, and the mechanical arm is controlled by the wireless control module to bring the infrared spectrum detection device close to the insulator to be detected, the wireless control module can receive the infrared spectrum data detected by the infrared spectrum detection device and transmit it to the control end transmitted to the ground, and the system is used to execute the method according to claim 1.

6. The in-situ insulator aging degree infrared spectrum detection system according to claim 5, characterized in that: The infrared spectrum detection device includes an infrared spectrometer, an infrared light source and an infrared fiber optic probe. The infrared fiber optic probe is connected to the infrared light source and the infrared spectrometer respectively through cables. The infrared fiber optic probe is arranged at the end of the robotic arm. The front end of the infrared fiber optic probe is clamped by the robotic arm and is close to the insulator to be detected.

7. An in-situ insulator aging degree infrared spectrum detection system as claimed in claim 5 or 6, characterized in that: The infrared spectrum data includes an emission spectrum array of the insulator to be detected and a reflection spectrum array of the insulator to be detected.

8. The in-situ insulator aging degree infrared spectrum detection system according to claim 5, characterized in that: The mechanical arm comprises a top servo fixed to the UAV and a plurality of joint servos, wherein the top servo is movably connected to one of the joint servos via a connecting frame and a flange, and the remaining joint servos are movably connected in sequence via the connecting frame and the flange.

9. The in-situ insulator aging degree infrared spectrum detection system according to claim 5, characterized in that: The control end calculates the received infrared spectrum data to obtain a first comparison value, a second comparison value and a threshold value, and when the first comparison value or the second comparison value is smaller than the threshold value, it is determined that the detected insulator is aged.

10. The in-situ insulator aging degree infrared spectrum detection system according to claim 6, characterized in that: Two cameras are symmetrically fixed on the outer side of the infrared optical fiber probe.

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