A method and device for detecting weak defects on the surface of an airline cable insulation

Abstract

The present application relates to a kind of aviation cable insulation surface weak defect detection method and system.The system includes: being arranged on the aviation cable to be detected, for the surface of the aviation cable to be detected is conducted with electric liquid spraying spray scanning unit;For the constant detection voltage and current of the aviation cable to be detected and detection unit, power supply unit;For the current data and position information of the scanning process of spray scanning unit are collected, and data acquisition unit is used, and for the current data and position information of the analysis of the control analysis unit of the movement of spray scanning unit are collected, and according to the analysis result confirms whether the insulation surface of the aviation line cable to be detected exists defect and the position information of defect, and generates report.Control analysis unit.The device and method of the present application can improve the detection rate of weak defect existing in the insulation resistance test technology of existing insulation resistance test technology, prevent the occurrence of arc, corona and other accident signs, greatly improve the safety and reliability of cable.

Description

Technical Field

[0001] This invention relates to the field of defect detection technology, and in particular to a method and apparatus for detecting weak defects on the surface of aviation cable insulation. Background Technology

[0002] Currently, with the development of more electric aircraft technology and the demand for energy conservation and emission reduction, the voltage level of the power system of more electric aircraft will be significantly increased compared to the current voltage level. In order to prevent the occurrence of electric arc and partial discharge, it is necessary to check the insulation integrity of aviation cables. The current insulation testing method mainly uses a high-voltage megohmmeter to test the insulation resistance between each wire core or between the wire core and the structural ground. Generally, the resistance value is required to be greater than 10MΩ.

[0003] Insulation resistance testing is generally performed before cable installation and during maintenance, but current insulation resistance testing methods have the following problems:

[0004] Minor damage to the cable insulation surface (such as small cracks) can be filled with air. The dielectric constant of air and the dielectric constant of the insulation material are on the same order of magnitude, and the gap is very small. If there are minor defects on the cable insulation surface, the insulation resistance will not change significantly. That is, the existing insulation resistance testing technology cannot detect minor defects on the cable insulation surface.

[0005] Existing testing technologies require applying high voltage to the cable under test, which can damage the cable itself, accelerate insulation aging, and the high voltage used may also cause electric shock accidents, posing certain dangers. Summary of the Invention

[0006] This invention discloses a method and apparatus for detecting weak defects on the surface of aviation cable insulation, in order to solve any of the above-mentioned and other potential problems in the prior art.

[0007] To solve the above problems, the technical solution of the present invention is: a system for detecting weak defects on the surface of aviation cable insulation, the system comprising: a spray scanning unit, a power supply unit, a data acquisition unit and a control and analysis unit;

[0008] The spraying and scanning unit is installed on the aviation cable to be inspected and is used to spray conductive liquid onto the surface of the aviation cable to complete the scanning and inspection.

[0009] The power supply unit is used to provide a constant detection voltage and current to the aviation cable and spray scanning unit to be inspected;

[0010] The data acquisition unit is used to acquire current data and position information during the scanning process of the spraying scanning unit;

[0011] The control and analysis unit is used to control the movement of the spraying and scanning unit, analyze the collected current data and position information, and confirm whether there are defects on the surface of the cable insulation of the aviation line to be inspected and the location information of the defects based on the analysis results, and generate a report.

[0012] Furthermore, the concentration of the conductive liquid is 2 mol / L to 5.4 mol / L sodium chloride.

[0013] Furthermore, the detection unit includes: a detection hollow cylinder, a spraying structure, a walking structure, and a conductive liquid storage structure;

[0014] The hollow cylinder has a detection chamber inside, the spraying structure is located inside the detection chamber, and the conductive liquid storage structure is located on the outer wall of the hollow cylinder, and the conductive liquid storage structure is connected to the spraying structure.

[0015] The walking structure is located at both ends of the detection hollow cylinder and is connected to the detection hollow cylinder.

[0016] Furthermore, the power supply unit is a storage battery, which is connected to the detection hollow cylinder and the aviation cable conductor to be tested via wires.

[0017] Furthermore, the data acquisition unit includes a ranging sensor and a current acquisition device;

[0018] The ranging sensor is disposed on the outer wall of the detection hollow cylinder;

[0019] The current acquisition device is connected to the wires between the power supply unit and the aviation line to be tested.

[0020] Furthermore, the current acquisition device is a high-precision ammeter or a small current sampling circuit.

[0021] Furthermore, the voltage of the battery is 28 volts.

[0022] Another object of the present invention is to provide a detection method using the above-described detection system, the detection method specifically comprising the following steps:

[0023] S1) Connect the components of the detection system, then set the spray scanning unit at the starting point of one end of the aviation cable to be tested, start the power supply unit to provide a constant voltage to the spray scanning unit and the aviation cable to be tested, and spray conductive liquid at the same time.

[0024] S2) The control and analysis unit issues a movement command, and the spraying and scanning unit moves at a constant speed along the aviation cable under test, while uniformly spraying conductive liquid onto the surface of the aviation cable under test. The data acquisition unit collects the current data at each point during the movement process and sends it to the control and analysis unit.

[0025] S3) The control and analysis unit compares the received current data according to the fault conditions, and confirms whether there are defects on the surface of the cable insulation of the aviation line to be tested and the location information of the defects based on the comparison results.

[0026] Furthermore, the method also includes a re-verification step S4).

[0027] S4) Based on the location of the fault, a manual re-inspection is conducted to confirm the presence of leakage, which indicates a defective cable.

[0028] Furthermore, the condition in S3) is: when the sampled current is 0-2mA, it is normal;

[0029] If the current collected is 0.2-0.5A, then it is a fault point.

[0030] The beneficial effects of the present invention are as follows: by adopting the above technical solution, the device and method of the present invention can improve the detection rate of weak defects on the surface of cable insulation that cannot be detected by existing insulation resistance testing technology, prevent the occurrence of accident symptoms such as electric arc and corona, and greatly improve the safety and reliability of cables. Attached Figure Description

[0031] Figure 1 This is a logic block diagram of a system for detecting weak defects on the surface of aviation cable insulation according to the present invention.

[0032] Figure 2 This is a flowchart of a method for detecting weak defects on the surface of aviation cable insulation according to the present invention.

[0033] In the picture:

[0034] 1. Spraying scanning unit, 1-1. Detection cylinder, 1-2. Spraying structure, 1-3. Walking structure, 2. Power supply unit, 3. Data acquisition and analysis unit, 3-1. Distance sensor, 3-2. Current acquisition device, 4. Control and analysis unit, 5. Aviation cable insulation layer, 6. Aviation cable conductor. Detailed Implementation

[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0036] like Figure 1As shown, the present invention provides a system for detecting weak defects on the surface of aviation cable insulation. The system includes: a spray scanning unit 1, a power supply unit 2, a data acquisition unit 3, and a control and analysis unit 4.

[0037] The spraying and scanning unit 1 is installed on the aviation cable to be inspected and is used to spray conductive liquid onto the surface of the aviation cable to be inspected to complete the scanning and inspection.

[0038] The power supply unit 2 is used to provide a constant detection voltage and current to the aviation cable and spray scanning unit to be inspected;

[0039] The data acquisition unit 3 is used to acquire current data and position information during the scanning process of the spraying scanning unit;

[0040] The control and analysis unit 4 is used to control the movement of the spraying and scanning unit 1, analyze the collected current data and position information, and confirm whether there are defects on the surface of the cable insulation of the aviation line to be inspected and the location information of the defects based on the analysis results, and generate a report.

[0041] The conductive liquid has a concentration of 2 mol / L to 5.4 mol / L sodium chloride.

[0042] The spraying scanning unit 1 includes: a detection hollow cylinder 1-1, a spraying structure 1-2, a walking structure 1-3, and a conductive liquid storage structure 1-4.

[0043] The hollow cylindrical test cylinder 1-1 has a test chamber inside, the spraying structure 1-1 is disposed inside the test chamber, and the conductive liquid storage structure 1-4 is disposed on the outer wall of the hollow cylindrical test cylinder 1-1, and the conductive liquid storage structure 1-4 is connected to the spraying structure 1-2.

[0044] The spraying structure 1-2 consists of several nozzles, which are evenly arranged on the inner sidewall of the detection chamber. The diameter of each nozzle is no greater than 0.5 mm.

[0045] The walking structure 1-3 is disposed at both ends of the detection hollow cylinder and connected to the detection hollow cylinder. The walking unit walking structure 1-3 is a rubber wheel.

[0046] The power supply unit 1-4 is a storage battery, which is connected to the detection hollow cylinder 1-1 and the aviation cable conductor 6 to be tested via wires.

[0047] The data acquisition unit 3 includes a ranging sensor 3-1 and a current acquisition device 3-2;

[0048] The ranging sensor 3-1 is disposed on the outer wall of the detection hollow cylinder 1-1;

[0049] The current acquisition device 3-2 is connected to the power supply unit 1-4 and the aviation line to be tested via a wire.

[0050] The current acquisition device 3-2 is a high-precision ammeter or a small current sampling circuit.

[0051] The battery has a voltage of 28 volts.

[0052] like Figure 2 As shown, a detection method using the above-described detection system specifically includes the following steps:

[0053] S1) Connect the components of the detection system, then set the spray scanning unit at the starting point of one end of the aviation cable to be tested, start the power supply unit to provide a constant voltage to the spray scanning unit and the aviation cable to be tested, and spray conductive liquid at the same time.

[0054] S2) The control and analysis unit issues a movement command, and the spraying and scanning unit moves at a constant speed along the aviation cable under test, while uniformly spraying conductive liquid onto the surface of the aviation cable under test. The data acquisition unit collects the current data at each point during the movement process and sends it to the control and analysis unit.

[0055] S3) The control and analysis unit compares the received current data according to the fault conditions, and confirms whether there are defects on the surface of the cable insulation of the aviation line to be tested and the location information of the defects based on the comparison results.

[0056] The method also includes a re-verification step S4).

[0057] S4) Based on the location of the fault, a manual re-inspection is conducted to confirm the presence of leakage, which indicates a defective cable.

[0058] Furthermore, the condition in S3) is: when the sampled current is 0-2mA, it is normal;

[0059] If the current collected is 0.2-0.5A, then it is a fault point.

[0060] Example:

[0061] Taking the testing of a 5m long aviation cable as an example, a defect is found on the insulation surface of the cable at a distance of 1m, which further illustrates the technical solution of the present invention.

[0062] First, inject a sodium chloride solution with a concentration of 5.4 mol / L (or other strong electrolyte solution) into the conductive liquid storage structure 1-4 of the spray scanning unit 1, without spraying the electrolyte solution for the time being.

[0063] The second step is to attach the test hollow cylinder 1-1 to the aviation cable to be tested, move the test hollow cylinder 1-1 to the beginning end of the cable to be tested, and then spray the electrolyte solution through the spraying structure 1-2 for 2 seconds, so that the electrolyte solution fills the inside of the test hollow cylinder 1-1.

[0064] The third step is to fill the detection hollow cylinder 1-1 with electrolyte solution and let it stand for 1 second to allow the electrolyte solution to fully contact the insulation surface of the cable under test. Then, under the control of the control and analysis unit 4, the detection hollow cylinder 1-1 is moved at a constant speed from the beginning to the end with the length of the detection hollow cylinder 1-1 as the step size. At the same time as it moves, the distance sensor 3-1 and the current acquisition device 3-2 record the position and current magnitude of the detection hollow cylinder 1-1, respectively.

[0065] After the detection hollow cylinder 1-1 moves to the end of the cable under test, the control analysis unit 4 generates a corresponding fault report based on the information fed back by the data acquisition unit 3. The report mainly includes the location and current magnitude. According to the test results and calculations, the current magnitude is 0-2mA when there is no fault and 0.2-0.5A when there is a fault.

[0066] Taking the insulation defect at 1m as an example, the report generated by the control analysis unit 4 shows that the current at the position of about 1m is 0.3A. Then, a manual re-inspection is carried out at 1m to prevent false detection. At this point, the detection is completed.

[0067] The foregoing has provided a detailed description of a method and system for detecting weak defects on the surface of aviation cable insulation, as provided in the embodiments of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and its core ideas; furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

[0068] Certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The terms "comprising" and "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising / including but not limited to". "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error. The following descriptions in the specification are preferred embodiments for carrying out this application; however, these descriptions are for the purpose of illustrating the general principles of this application and are not intended to limit the scope of this application. The scope of protection of this application shall be determined by the appended claims.

[0069] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes said element.

[0070] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0071] The foregoing description illustrates and describes several preferred embodiments of this application. However, as previously stated, it should be understood that this application is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the application concept described herein through the foregoing teachings or the technology or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of this application should be considered in accordance with the appended claims.

Claims

1. A system for detecting minor defects on the surface of aviation cable insulation, characterized in that, The detection system includes: a spray scanning unit, a power supply unit, a data acquisition unit, and a control and analysis unit; The spraying and scanning unit is installed on the aviation cable to be inspected and is used to spray conductive liquid onto the surface of the aviation cable to complete the scanning and inspection. The power supply unit is used to provide a constant detection voltage and current to the aviation cable and spray scanning unit to be inspected; The data acquisition unit is used to acquire current data and position information during the scanning process of the spraying scanning unit; The control and analysis unit is used to control the movement of the spraying and scanning unit, analyze the collected current data and position information, and confirm whether there are defects on the surface of the cable insulation of the aviation line to be inspected and the location information of the defects based on the analysis results, and generate a report. The spraying scanning unit includes: a detection hollow cylinder, a spraying structure, a walking structure, and a conductive liquid storage structure; The hollow cylinder has a detection chamber inside, the spraying structure is located inside the detection chamber, and the conductive liquid storage structure is located on the outer wall of the hollow cylinder, and the conductive liquid storage structure is connected to the spraying structure. The spraying structure consists of several nozzles, which are evenly arranged on the inner sidewall of the detection chamber, and the diameter of each nozzle is no greater than 0.5 mm. The walking structure is located at both ends of the detection hollow cylinder and connected to the detection hollow cylinder. The walking structure is a rubber wheel.

2. The detection system according to claim 1, characterized in that, The conductive liquid has a concentration of 2 mol / L to 5.4 mol / L sodium chloride.

3. The detection system according to claim 1, characterized in that, The power supply unit is a storage battery, which is connected to the detection hollow cylinder and the aviation cable conductor to be tested via wires.

4. The detection system according to claim 3, characterized in that, The data acquisition unit includes a ranging sensor and a current acquisition device; The ranging sensor is disposed on the outer wall of the detection hollow cylinder; The current acquisition device is connected to the wires between the power supply unit and the aviation line to be tested.

5. The detection system according to claim 4, characterized in that, The current acquisition device is a high-precision ammeter or a small current sampling circuit.

6. The detection system according to claim 3, characterized in that, The battery has a voltage of 28 volts.

7. A detection method using the detection system as described in any one of claims 1-6, characterized in that, The detection method specifically includes the following steps: S1) Connect the components of the detection system, then set the spray scanning unit at the starting point of one end of the aviation cable to be tested, start the power supply unit to provide a constant voltage to the spray scanning unit and the aviation cable to be tested, and spray conductive liquid at the same time. S2) The control and analysis unit issues a movement command, and the spraying and scanning unit moves at a constant speed along the aviation cable under test, while uniformly spraying conductive liquid onto the surface of the aviation cable under test. The data acquisition unit collects the current data at each point during the movement process and sends it to the control and analysis unit. S3) The control and analysis unit compares the received current data according to the fault conditions, and confirms whether there are defects on the surface of the cable insulation of the aviation line to be tested and the location information of the defects based on the comparison results.

8. The method according to claim 7, characterized in that, The method also includes a re-verification step S4). S4) Based on the location of the fault, a manual re-inspection is conducted to confirm the presence of leakage, which indicates a defective cable.

9. The method according to claim 7, characterized in that, The condition in S3) is: when the sampled current is 0-2mA, it is normal; If the current collected is 0.2-0.5A, then it is a fault point.

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