Instrument for non-contact detection of insulator defects of drop-out fuse

Abstract

The invention relates to an instrument for detecting defects of an insulator of a drop-out fuse in a non-contact manner. The instrument judges whether the drop-out fuse insulator has defects or not by comparing the change rule of the difference between the temperature of the insulator and the environment temperature with the change rule of the difference without defects under the heating condition. And a reference temperature difference change rule is arranged in the instrument and is used for comparing with the actually detected temperature difference change so as to determine the state of the insulator. The instrument comprises a plurality of functional modules, such as a camera module, a low-power laser, a high-power laser, a laser ranging module, a thermal imaging module and the like, and the modules are controlled by a single chip microcomputer to realize automatic detection. In the detection process, the high-power laser heats the preset position of the fuse, the thermal imaging module measures the temperature, and data are transmitted through the wireless module. The drop-out fuse insulator defect detection instrument not only avoids direct contact with the insulator, but also improves the accuracy and efficiency of defect detection.

Description

Technical Field

[0001] The invention relates to electrical equipment detection technology, in particular to a non-contact detection instrument for judging insulator defects of drop-out fuses based on whether the heat transfer process of the insulator is normal, and belongs to the field of power system monitoring. Background Art

[0002] Drop-out fuses are vital overload protection devices in power systems. Their core function is to quickly cut off the circuit when the current exceeds the set value to ensure the safety of equipment and circuits. However, in Northwest my country, frequent strong winds and significant temperature differences between day and night pose a severe challenge to the reliability of fuses. Drop-out fuses are mainly composed of insulators, fixed ends, fuse tubes, inlet / outlet terminals, and moving / static contacts. As an important component of the fuse, the insulator not only supports the entire device, but also performs an insulating function. Its structural characteristics make the connection between the fixed end and the insulator a weak link where stress is concentrated, which can easily lead to fuse failure, resulting in serious economic losses and waste of resources.

[0003] The failure of porcelain insulators may be manifested as porcelain body fracture, cement adhesive swelling due to moisture absorption, or cement adhesive being squeezed out of the jelly-like holes in the porcelain bottle when the insulator is subjected to large stress but not broken. In either case, the connection between the fixed end and the insulator will eventually loosen and fail. In the early stage of failure, this looseness may be very hidden and difficult to detect with the naked eye, so it is necessary to design a special instrument to detect the contact status of the two parts.

[0004] As a commonly used protective device in power systems, the health of the insulators of drop-out fuses is crucial to the safety of the entire system. Traditional detection methods often rely on ultrasonic detection, ultraviolet imaging detection and other methods, which have many operational restrictions and low detection efficiency. Therefore, the development of a non-contact and high-precision detection instrument has become an inevitable demand. Summary of the invention

[0005] The purpose of the present invention is to provide an instrument that can accurately detect defects in the insulator of a drop-out fuse in a non-contact manner. The instrument is based on the fact that defects in the insulator (such as cracks in any part) change the heat transfer process of the insulator, so that the law of the temperature difference between a specified point and the ambient temperature under the same specified heating conditions is different from the law when there is no defect, and then judge whether the insulator has defects based on this difference in degree.

[0006] The technical solution of the present invention is as follows: an instrument for non-contact detection of defects in drop-type fuse insulators, comprising an instrument body and a receiving end. The instrument body is provided with a device shell, and a thermal imaging module, a camera module, a low-power laser, a laser ranging module, a high-power laser, a wireless data transmission module, a power supply, a heat sink, and a single-chip control module are fixed inside the device shell. A connection port for connecting with an insulating rod is fixed at the bottom of the instrument body. The lenses of the thermal imaging module and the camera module and the transmission ports of the low-power laser, the laser ranging module, and the high-power laser are all located on the same side wall of the device shell. The surface of the receiving end is provided with buttons and a high-definition display screen, and a control circuit is contained inside. The side wall contains a wireless data receiving module. The camera module is used to find the target to be tested, and the low-power laser is used to focus on the defective point of the drop-type fuse insulator (mostly the connection between the fixed end and the insulator). The defective point is caused by the defective drop-type insulator that has been defective in the past. According to statistics of fuse insulators, the laser ranging module is used to determine whether the focus is completed, the high-power laser is used to heat the defective point, the thermal imaging module is used to detect the temperature signal of the heated defective point, the wireless data transmitting module is used to transmit the defective point detection temperature signal measured by the thermal imaging module, the wireless data receiving module receives the data signal of the wireless data transmitting module, the data signal received by the wireless data receiving module is transmitted to the internal control circuit of the receiving end, the control circuit calculates the change data of the difference between the defective point detection temperature and the ambient temperature according to the temperature detection data of the thermal imaging module, the high-definition display screen displays the change data as a visible temperature change curve, the temperature change curve is compared with the temperature change curve of the same heat flux heating of the defect-free drop-out fuse insulator stored in the internal control circuit of the receiving end, and when the compliance exceeds a specified compliance, it is determined that the drop-out fuse insulator is defective.

[0007] The single-chip control module can control the working states of the camera module, the low-power laser, the high-power laser, the laser ranging module, the thermal imaging module and the radiator, can read the distance signal provided by the laser ranging module, and can read the temperature signal measured by the thermal imaging module.

[0008] Data is transmitted between the wireless data transmission module and the receiving end to transmit the control information of the camera module, low-power laser, high-power laser, laser ranging module and thermal imaging module.

[0009] Furthermore, a side wall close to the radiator is provided with a heat dissipation port.

[0010] Preferably, the connection port is a threaded structure.

[0011] The beneficial effects of the present invention include: using laser ranging, lasers of different powers, and thermal imaging to obtain the temperature difference between the heating temperature of the insulator defect of the drop-out fuse and the ambient temperature; non-contact detection enables the inspector to obtain the detection data on the ground, learn the degree of compliance, and determine possible defects; the invention is easy to use, highly safe, and quick to detect. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 The overall structure of the instrument body is shown; Figure 2 The structure of the receiving end is shown; Figure 3 The use process of the instrument is shown; Figure 4 Demonstrated the module interactions during the detection process; Figure 5 The figure shows the temperature variation pattern preset by the instrument (dashed line) and the variation pattern obtained by detection (solid line) displayed on the high-definition display screen. DETAILED DESCRIPTION

[0013] An instrument for non-contact detection of insulator defects of drop-out fuses comprises an instrument body 1 and a receiving end 20, characterized in that the instrument body 1 is provided with a device housing 18, a thermal imaging module 13, a camera module 10, a low-power laser 11, a laser ranging module 12, a high-power laser 5, a wireless data transmitting module 14, a power supply 17, a heat sink 16, and a single-chip control module 15 are fixed inside the device housing 18, a heat dissipation port is provided on the side wall close to the heat sink 16, a threaded structure connection port 19 for connecting with an insulating rod is fixed at the bottom of the instrument body 1, the lens of the thermal imaging module 13, the camera module 10 and the transmitting ports of the low-power laser 11, the laser ranging module 12, and the high-power laser 5 are all located on the same side wall of the device housing 18, a button 21 and a high-definition display screen 23 are provided on the surface of the receiving end 20, a control circuit is contained inside, and a wireless data receiving module 22 is contained on the side wall. The camera module 10 is used to find the target to be measured and observe the fuse and the irradiation position of the laser. The low-power laser 11 is used for focusing and locating the defective point of the drop-out fuse insulator, which is obtained by statistics of the drop-out fuse insulators with defects in the past. The laser distance measurement module 12 is used to determine whether the focusing is completed, the high-power laser 5 is used to heat the defective point, the thermal imaging module 13 is used to detect the temperature signal of the heated defective point, the wireless data transmission module 14 is used to transmit the defective point detection temperature signal measured by the thermal imaging module 13, the wireless data receiving module 22 receives the data signal of the wireless data transmission module 14, and the data signal received by the wireless data receiving module 22 is transmitted to the internal control circuit of the receiving end 20. The control circuit calculates the change data of the difference between the defective point detection temperature and the ambient temperature according to the temperature detection data of the thermal imaging module 13, and the high-definition display screen 23 displays the change data as a visible temperature change curve, which is compared with the temperature change curve of the same heat flux heating of the defect-free drop-out fuse insulator stored in the internal control circuit of the receiving end 20. When the compliance exceeds a specified compliance, it is determined that the drop-out fuse insulator has defects.

[0014] The single-chip control module 15 can control the working states of the camera module 10, the low-power laser 11, the high-power laser 5, the laser ranging module 12, the thermal imaging module 13 and the radiator 16, can read the distance signal provided by the laser ranging module 12, and can read the temperature signal measured by the thermal imaging module 13.

[0015] Data is transmitted between the wireless data transmitting module 14 and the receiving end 20 to transmit control information of the camera module 10 , the low-power laser 11 , the high-power laser 5 , the laser ranging module 12 , and the thermal imaging module 13 .

[0016] As mentioned above, the instrument presets the variation law of the temperature difference between a defective point and the ambient temperature under specified heating conditions when the insulator is free of defects. This law is to use a high-power laser to perform non-contact heating at a specified position with a specific heat flux, and then record the variation of the temperature difference between the defective point and the ambient temperature over time. During the test, by comparing the conformity of the actually measured temperature difference variation law with the preset law, when the conformity exceeds the set value, it can be judged that the insulator has defects.

[0017] The high-definition display screen 23 displays information including date, power information, preset temperature variation pattern and measured variation pattern, determination result, and test status.

Claims

1. An instrument for non-contact detection of insulator defects of a drop-out fuse, comprising an instrument body (1) and a receiving end (20), characterized in that: The instrument body (1) is provided with a device housing (18), and a thermal imaging module (13), a camera module (10), a low-power laser (11), a laser ranging module (12), a high-power laser (5), a wireless data transmission module (14), a power supply (17), a heat sink (16), and a single-chip control module (15) are fixed inside the device housing (18). A connection port (19) for connecting to an insulating rod is fixed at the bottom of the instrument body (1). The lenses of the thermal imaging module (13), the camera module (10) and the transmission ports of the low-power laser (11), the laser ranging module (12), and the high-power laser (5) are all located on the same side wall of the device housing (18). The surface of the receiving end (20) is provided with a button (21) and a high-definition display screen (23), and the inside contains a control circuit. The side wall contains a wireless data receiving module (22). The camera module (10) is used to find a target to be measured, and the low-power laser (11) is used to focus on a defective point of a drop-type fuse insulator. The defective point is caused by a drop-type fuse that has previously been defective. The laser distance measuring module (12) is used to determine whether the focus is completed, the high-power laser (5) is used to heat the defective point, the thermal imaging module (13) is used to detect the temperature signal of the heated defective point, the wireless data transmitting module (14) is used to transmit the defective point detection temperature signal measured by the thermal imaging module (13), the wireless data receiving module (22) receives the data signal of the wireless data transmitting module (14), the data signal received by the wireless data receiving module (22) is transmitted to the internal control circuit of the receiving end (20), the control circuit calculates the change data of the difference between the defective point detection temperature and the ambient temperature according to the temperature detection data of the thermal imaging module (13), the high-definition display screen (23) displays the change data as a visible temperature change curve, the temperature change curve is compared with the temperature change curve of the same heat flux heating of the defective drop-out fuse insulator stored in the internal control circuit of the receiving end (20), and when the compliance exceeds a specified compliance, it is determined that the drop-out fuse insulator has a defect.

2. According to claim 1, a non-contact instrument for detecting insulator defects of drop-out fuses, characterized in that: The single-chip control module (15) is capable of controlling the working states of the camera module (10), the low-power laser (11), the high-power laser (5), the laser distance measuring module (12), the thermal imaging module (13) and the heat sink (16), and is capable of reading a distance signal provided by the laser distance measuring module (12), and is capable of reading a temperature signal measured by the thermal imaging module (13).

3. The instrument for non-contact detection of insulator defects of drop-out fuses according to claim 1, characterized in that: Data is transferred via the wireless data transmission module (14) and the receiving end (20) to transmit control information of the camera module (10), the low-power laser (11), the high-power laser (5), the laser distance measurement module (12), and the thermal imaging module (13).

4. The instrument for non-contact detection of insulator defects of drop-out fuses according to claim 1, characterized in that: The side wall close to the radiator (16) is provided with a heat dissipation opening.

5. The instrument for non-contact detection of insulator defects of drop-out fuses according to claim 1, characterized in that: The connecting port (19) is a threaded structure.

Images