Cable test equipment and test method

Abstract

The embodiment of the invention provides cable testing equipment and a testing method, and relates to the technical field of cable testing, the cable testing equipment comprises a first container, the first container is used for installing a to-be-tested cable and containing a salt solution, and the to-be-tested cable is immersed in the salt solution; the second container is used for containing insulating liquid, the first container is arranged in the second container, and at least part of the first container is immersed in the insulating liquid; and the electric signal generator is used for being connected with the to-be-tested cable through a wire so as to provide a voltage signal for the to-be-tested cable. According to the cable test equipment and the test method provided by the embodiment of the invention, the problem of long time consumption of water tree resistance test of the cable in the prior art is solved.

Description

Technical Field

[0001] The present application relates to the technical field of cable testing, and in particular to a cable testing device and a cable testing method. Background Art

[0002] Water treeing is one of the main causes of premature failure of cables. Therefore, the evaluation of the water tree resistance and remaining life of the insulation materials on cables is an important issue facing cables.

[0003] In the related art, the water tree resistance performance test method of the cable is usually to conduct a 2-year water tree resistance performance test at 50Hz; or to conduct a 3000-hour (i.e. more than 120 days) water tree resistance performance test at 500Hz.

[0004] However, the above-mentioned water tree resistance test methods are time-consuming and have low test efficiency. Summary of the invention

[0005] The embodiments of the present application provide a cable testing device and a cable testing method to solve the problem that the cable water tree resistance performance test in the prior art takes a long time.

[0006] In a first aspect, an embodiment of the present application provides a cable testing device, including:

[0007] A first container, wherein the first container is used to install the cable to be tested and contain a saline solution, and the cable to be tested is immersed in the saline solution;

[0008] a second container, the second container being used to hold insulating liquid, the first container being disposed in the second container, and the first container being at least partially immersed in the insulating liquid;

[0009] An electrical signal generator is used to be connected to the cable to be tested through a conductor to provide a voltage signal to the cable to be tested.

[0010] In a possible implementation manner, both side walls of the first container are provided with through holes for the cable to be tested to pass through; and two sealing members are further included, and the sealing members are used to seal the gap between the cable to be tested and the edge of the through hole.

[0011] In a possible implementation, two through holes are provided and are respectively disposed on two opposite side walls of the first container. The through holes extend vertically and have an open structure at the upper ends.

[0012] In a possible implementation manner, the sealing member includes a sealing flange, the sealing flange is used to be sleeved on the cable to be tested, the sealing flange is connected to the first container, and the sealing flange covers the through hole. In a possible implementation manner, the sealing member also includes a first sealing ring, the first sealing ring is used to be sleeved on the cable to be tested, and the first sealing ring is coaxially arranged on the inner side of the sealing flange.

[0013] In a possible implementation manner, the sealing member further includes a second sealing ring, the second sealing ring is used to be sleeved on the cable to be tested, and the second sealing ring is clamped between the sealing flange and the first container.

[0014] In a possible implementation manner, a grounding member is further included, and the grounding member is disposed on the first container. The grounding member is used to be connected to a ground wire to ground the first container.

[0015] In a possible implementation manner, the first container includes a sealing cover and a container body having an opening, the container body is used to install the cable to be tested and contain the salt solution, and the sealing cover is arranged to cover the opening of the container body.

[0016] In a second aspect, an embodiment of the present application further provides a method for testing a cable test device based on any one of the above embodiments, comprising the following steps:

[0017] Fixing the cable to be tested on a first container in the cable testing device, and adding a saline solution into the first container;

[0018] adding insulating liquid to a second container in a testing device for the cable;

[0019] The frequency and voltage transmitted to the cable to be tested by an electrical signal generator in the cable testing equipment;

[0020] After the test, the water tree condition on the tested cable is observed and recorded.

[0021] In a possible implementation manner, observing and recording the water tree condition on the cable to be tested includes:

[0022] Taking a plurality of slices from the cable to be tested, and staining each of the slices with a stain to show the water tree;

[0023] The water tree was observed under a microscope and its parameters were recorded.

[0024] The embodiment of the present application provides a cable testing device and a testing method, wherein the cable testing device includes a first container, the first container is used to install the cable to be tested and contain a salt solution, and the cable to be tested is immersed in the salt solution; a second container, the second container is used to contain an insulating liquid, the first container is arranged in the second container, and the first container is at least partially immersed in the insulating liquid; an electrical signal generator, the electrical signal generator is used to connect to the cable to be tested through a wire to provide a voltage signal to the cable to be tested. Therefore, during the test, a high-voltage and high-frequency signal is transmitted to the cable to be tested through the electrical signal generator, and at the same time, with the help of the salt solution, the generation and growth of the water tree on the cable to be tested are accelerated, the water tree growth efficiency is greatly improved, the time consumption of the anti-water tree performance test process is shortened, the test efficiency is improved, and the problem of the long time consumption of the anti-water tree performance test of the cable in the prior art is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0026] Figure 1 A schematic diagram of the structure of a cable testing device provided in this application;

[0027] Figure 2 for Figure 1 Schematic diagram of the structure of the container body.

[0028] Description of reference numerals:

[0029] 10-cable to be tested;

[0030] 100 - first container; 110 - cover; 120 - container body; 130 - through hole;

[0031] 200 - second container;

[0032] 300-Electrical signal generator;

[0033] 400- grounding piece;

[0034] 500-seal; 510-sealing flange;

[0035] 600 - Analyzer;

[0036] 700-controller;

[0037] 800-sound and light alarm.

[0038] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0039] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0040] In the related art, water tree is one of the main reasons for premature failure of cables. Therefore, the evaluation of the anti-water tree performance and remaining life of the insulation material on the cable is an important issue facing the cable.

[0041] The water tree resistance test of cables is usually conducted at 50Hz for 2 years, or at 500Hz for 3000 hours (i.e. more than 120 days). During the water tree resistance test, water trees are generated on the cables in a set environment, and the water tree conditions are finally tested.

[0042] However, the above-mentioned water tree resistance test methods are time-consuming and have low test efficiency.

[0043] Therefore, the embodiment of the present application provides a cable testing device and a testing method, wherein the cable testing device includes: a first container, the first container is used to install the cable to be tested and contain the salt solution, and the cable to be tested is immersed in the salt solution; a second container, the second container is used to contain the insulating liquid, the first container is arranged in the second container, and the first container is at least partially immersed in the insulating liquid; an electrical signal generator, the electrical signal generator is used to connect to the cable to be tested through a wire to provide a voltage signal to the cable to be tested. Therefore, during the test, a high-voltage and high-frequency signal is transmitted to the cable to be tested through the electrical signal generator, and at the same time, with the help of the salt solution, the generation and growth of the water tree on the cable to be tested are accelerated, the water tree growth efficiency is greatly improved, the time consumption of the anti-water tree performance test process is shortened, the test efficiency is improved, and the problem of the long time consumption of the anti-water tree performance test of the cable in the prior art is solved.

[0044] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0045] like Figure 1 As shown, a cable testing device provided in an embodiment of the present application includes:

[0046] A first container 100, the first container 100 is used to install the cable to be tested 10 and contain the salt solution, and immerse the cable to be tested 10 in the salt solution;

[0047] A second container 200, the second container 200 is used to contain insulating liquid, the first container 100 is disposed in the second container 200, and the first container 100 is at least partially immersed in the insulating liquid;

[0048] The electrical signal generator 300 is used to be connected to the cable under test 10 through a wire to provide a voltage signal to the cable under test 10 .

[0049] In the embodiment of the present application, the first container 100 contains a salt solution, which may be sodium chloride or other; the second container 200 contains an insulating liquid, which may be insulating oil or other, and is not limited thereto. The first container 100 is disposed in the second container 200, so that the first container 100 is immersed in the insulating liquid, so that the insulating liquid can play a better insulating role during the test process.

[0050] Secondly, the cable 10 to be tested only needs to be installed in the first container 100 and immersed in the salt solution, and the cable 10 to be tested is connected to the electrical signal generator 300 to start the water tree resistance test.

[0051] It should be noted that the electrical signal generator 300 can be arranged around the second container 200. When implemented, the electrical signal generator 300 and the cable to be tested 10 can be electrically connected to each other using additional wires (not shown in the figure), and there is no limitation to this; in addition, the specific model of the electrical signal generator 300 is also not limited.

[0052] During the test, the cable 10 to be tested is installed in the first container 100 and connected to the electrical signal generator 300 . Then, a saline solution is added to the first container 100 , and then an insulating liquid is added to the second container 200 . Finally, the electrical signal generator 300 is operated.

[0053] Therefore, a high-voltage and high-frequency signal is transmitted to the cable 10 to be tested through the electrical signal generator 300, and at the same time, with the help of the salt solution, the generation and growth of the water tree on the cable 10 to be tested are accelerated, the water tree growth efficiency is greatly improved, the time consumption of the anti-water tree performance test process is shortened, the test efficiency is improved, and the problem of long time consumption of the anti-water tree performance test of the cable in the prior art is solved.

[0054] During implementation, for example, the high-voltage high-frequency signal transmitted by the electrical signal generator to the cable to be tested can be set to 30kHz, and the voltage applied during the test is 3.8kV per millimeter of insulating material. At the same time, with the help of saline solution, the generation and growth of water trees on the cable to be tested are accelerated. Compared with the time consumed under 50Hz (about 2 years) or 500Hz (about 120 days), the water tree growth efficiency is greatly improved, and the test time is shortened to about 14 days on the basis of presenting a similar degree of water tree conditions. In other embodiments, the frequency and voltage transmitted to the cable to be tested 10 can also be reasonably set according to actual needs.

[0055] When implementing, Figure 1 As shown, an analyzer 600, a controller 700 and an audible and visual alarm 800 may also be added, and the models are not limited. Thus, the online monitoring and analysis of the test data are performed by the analyzer 600. The controller 700 is electrically connected to the electric signal generator 300, so that the voltage value of the electric signal generator 300 is controlled by the controller 700, and the current voltage, frequency or other information is displayed. The audible and visual alarm 800 is electrically connected to the electric signal generator 300, so that the abnormal operation state of the electric signal generator 300 is alarmed by the audible and visual alarm 800, so as to ensure the safety of the test process and the accuracy of the test.

[0056] like Figure 1 As shown, in some embodiments, the first container 100 includes a cover 110 and a container body 120 having an opening. The container body 120 is used to install the cable 10 to be tested and contain the salt solution. The cover 110 covers the opening of the container body 120.

[0057] The container body 120 is an upper opening structure, and the container body 120 is arranged in a spaced manner in the second container 200, and the cover 110 is covered on the opening of the container body 120. The cover 110 can be connected to the container body 120 by snap connection, buckle connection, screw connection or other methods, which are not limited. The saline solution is contained in the container body 120, and the cable 10 to be tested is installed in the container body 120.

[0058] During implementation, an insulating pad (such as a rubber block, a silicone block or other) may be arranged at the bottom of the container body 120, so that the container body 120 stands in the second container 200 through the insulating pad. At the same time, a certain gap is ensured between the peripheral side of the container body 120 and the side wall of the second container 200, so as to ensure that the insulating liquid fully exerts its insulating effect around the container body 120 during the test.

[0059] It should be noted that the second container 200 may be box-shaped, box-shaped or other structures, which are not limited. In other embodiments, a base may be further provided, the base is fixed to the ground, and the second container 200 is installed on the base to ensure the stability of the second container 200.

[0060] like Figure 1 As shown, further, the cable testing device further includes a grounding member 400 , which is disposed on the first container 100 , and the grounding member 400 is used to be connected to a ground wire to ground the first container 100 .

[0061] It should be noted that the grounding member 400 is disposed on at least one of the cover 110 and the container body 120. In the embodiment of the present application, the grounding member 400 may be an electrode column, and the grounding member 400 may be fixed to the upper surface of the cover 110 by welding, screwing or other means. During implementation, it is only necessary to connect the grounding member 400 to the ground wire.

[0062] It is understandable that after the cover 110 covers the container body 120, the cover 110 is in contact with the container body 120 and the saline solution, so that the saline solution, the cable to be tested 10 and the first container 100 are grounded as a whole, further ensuring the safety of the test process.

[0063] like Figure 1 As shown, further, there are multiple grounding members 400 , and each grounding member 400 is disposed on the cover 110 .

[0064] Thus, the entire first container 100 can be grounded more fully.

[0065] Of course, the number of the grounding pieces 400 can be reasonably set according to actual needs, for example, set to two, and the grounding piece 400 can also be fixed on the container body 120, without limitation.

[0066] like Figure 1 and Figure 2 As shown, in some embodiments, both side walls of the first container 100 are provided with through holes 130 for the cable 10 to be tested to enter and exit; the cable testing equipment also includes two seals 500, which are used to seal the gap between the cable 10 to be tested and the edge of the through hole 130.

[0067] Furthermore, two through holes 130 are provided and are respectively disposed on two opposite side walls of the first container 100 . The through holes 130 extend vertically and have an open structure at the upper end.

[0068] In the embodiment of the present application, the through hole 130 is opened on the container body 120, and the two opposite side walls of the container body 120 both have a through hole 130. The through hole 130 is a vertically extending structure, and the upper end of the through hole 130 is connected to the opening edge of the container body 120.

[0069] When installing the cable 10 to be tested, it only needs to be inserted into the two through holes 130 from top to bottom, so that the cable 10 to be tested is installed in the container body 120, thereby making the installation process of the cable 10 to be tested more convenient and ensuring that the cable 10 to be tested can be fully immersed in the salt solution. In this regard, the gap between the edge of the through hole 130 and the end of the cable 10 to be tested is also sealed by a sealing member 500.

[0070] Specifically, two seals 500 are provided, and the two seals 500 are respectively provided at the two ends of the cable to be tested 10. The seals 500 are sleeved on the ends of the cable to be tested 10, and the seals 500 are attached to the outer wall of the container body 120 and cover the through hole 130, thereby reducing the possibility of the salt solution leaking outward from the through hole 130.

[0071] like Figure 2 As shown, further, the sealing member 500 includes a sealing flange 510 , which is used to be sleeved on the cable to be tested 10 , and the sealing flange 510 is connected to the first container 100 , and the sealing flange 510 covers the through hole 130 .

[0072] The sealing flange 510 is annular and is sleeved on the cable 10 to be tested. The sealing flange 510 can be fixed to the outer wall of the container body 120 by screwing or other means, so that the sealing flange 510 covers the through hole 130 .

[0073] During implementation, for example, multiple screws can be welded and fixed on the outer wall of the container body 120, and multiple connecting holes can be opened on the sealing flange 510, so that the sealing flange 510 can be simultaneously sleeved on multiple screws, and finally multiple nuts can be installed to lock the sealing flange 510 on the outer wall of the container body 120.

[0074] In some embodiments, the sealing member 500 further includes a first sealing ring, which is used to be sleeved on the cable to be tested 10 , and the first sealing ring is coaxially disposed on the inner side of the sealing flange 510 .

[0075] It should be noted that the first sealing ring can be made of rubber, silicone or other materials. The first sealing ring is coaxially embedded in the inner side of the sealing flange 510, so that when the sealing flange 510 is sleeved on the cable to be tested 10, the first sealing ring will contact the cable to be tested 10, thereby further improving the sealing effect of the gap between the cable to be tested 10 and the sealing flange 510.

[0076] The sealing member 500 further includes a second sealing ring, which is used to be sleeved on the cable to be tested 10 , and the second sealing ring is clamped between the sealing flange 510 and the outer wall of the first container 100 .

[0077] It should be noted that the second sealing ring can be made of rubber, silicone or other materials. The second sealing ring is coaxially embedded on the side of the sealing flange 510 facing the container body 120, so that when the sealing flange 510 is fastened to the outer wall of the container body 120, the second sealing ring is clamped between the sealing flange 510 and the outer wall of the container body 120, thereby further improving the sealing effect of the gap between the sealing flange 510 and the outer wall of the container body 120.

[0078] In other embodiments, the second sealing ring can also be set as a sheet structure, so that the second sealing ring covers the side of the sealing flange 510 facing the container body 120, so that after the sealing flange 510 is fixed to the outer wall of the container body 120, the through hole 130 can be covered by the second sealing ring, thereby further improving the sealing effect of the through hole 130.

[0079] In other embodiments, the sealing member 500 may further include a rotating sealing ring embedded in the sealing flange 510 , and the rotating sealing ring is sleeved on the cable 10 to be tested.

[0080] In summary, the cable test equipment provided by the embodiment of the present application, during the test, install the cable 10 to be tested in the first container 100, connect the cable 10 to the electric signal generator 300, then add the salt solution into the first container 100, add the insulating liquid into the second container 200, and finally operate the electric signal generator 300. Thus, the high-voltage and high-frequency signal is transmitted to the cable 10 to be tested through the electric signal generator 300, and at the same time, with the help of the salt solution, the generation and growth of the water tree on the cable 10 to be tested are accelerated, the water tree growth efficiency is greatly improved, the time consumption of the anti-water tree performance test process is shortened, the test efficiency is improved, and the problem of long time consumption of the anti-water tree performance test of the cable in the prior art is solved.

[0081] The present application also provides a method for testing a cable test device based on any one of the above embodiments, comprising the following steps:

[0082] Prepare a cable to be tested 10;

[0083] Fixing the cable 10 to be tested on a first container 100 in a cable testing device, and adding a saline solution into the first container 100;

[0084] Adding insulating liquid to the second container 200 in the cable testing equipment;

[0085] The frequency and voltage transmitted to the cable 10 to be tested by the electrical signal generator 300 in the cable testing equipment, then the temperature of the test environment is determined, and the test is started;

[0086] After the test is completed, the water tree condition on the cable 10 to be tested is observed and recorded.

[0087] It should be noted that the frequency can be set to 30kHz, the voltage applied during the test is 3.8kV per millimeter of insulation, the test temperature is kept constant at 30°C, and the test time is 14 days. Of course, the test frequency, voltage, temperature and time can also be set to other values.

[0088] Further, observing and recording the water tree condition on the cable 10 to be tested includes: taking multiple slices from the cable 10 to be tested, staining each slice with a dye (such as methylene blue) to show the water tree, then observing the water tree condition with a microscope, and recording parameters.

[0089] During implementation, the following parameters are verified and recorded: the number of bow-tie and dendrite-shaped water trees, the maximum length of bow-tie and dendrite-shaped water trees, and the number of large bow-tie and dendrite-shaped water trees. The length of large bow-tie water trees must exceed 150µm, and the length of large dendrite water trees must exceed 100µm. Secondly, based on the recorded test parameters, a color ranking standard is established to analyze the water tree situation. For example, the color can change from green (best result) to yellow, orange, and red (poor result) based on the shape, length, and number of water trees.

[0090] Therefore, the cable testing method provided in the embodiment of the present application can accelerate the generation and growth of water trees on the cable 10 to be tested, greatly improve the water tree growth efficiency, shorten the time consumption of the anti-water tree performance testing process, improve the testing efficiency, and solve the problem of long time consumption of the anti-water tree performance testing of the cable in the prior art.

[0091] Finally, it should be noted that those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary technical means in the art not disclosed by the present invention, are not limited to the precise structure described above and shown in the drawings, and may be modified and changed in various ways without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A cable testing device, characterized in that: include: A first container (100), the first container (100) being used to install the cable to be tested (10) and contain a saline solution, and to immerse the cable to be tested (10) in the saline solution; a second container (200), the second container (200) being used to contain insulating liquid, the first container (100) being arranged in the second container (200), and the first container (100) being at least partially immersed in the insulating liquid; An electrical signal generator (300) is used to be connected to the cable to be tested (10) via a wire, so as to provide a voltage signal to the cable to be tested (10).

2. The cable testing device according to claim 1, characterized in that: Both side walls of the first container (100) are provided with through holes (130) for the cable to be tested (10) to enter and exit; It also includes two sealing members (500), wherein the sealing members (500) are used to seal the gap between the cable to be tested (10) and the edge of the through hole (130).

3. The cable testing device according to claim 2, characterized in that: Two through holes (130) are provided and are respectively arranged on two opposite side walls of the first container (100); the through holes (130) extend vertically and have an open structure at the upper end.

4. The cable testing device according to claim 2, characterized in that: The sealing member (500) comprises a sealing flange (510), the sealing flange (510) being used for being sleeved on the cable to be tested (10), the sealing flange (510) being connected to the first container (100), and the sealing flange (510) covering the through hole (130).

5. The cable testing device according to claim 4, characterized in that: The sealing element (500) further comprises a first sealing ring, the first sealing ring being used to be sleeved on the cable to be tested (10), and the first sealing ring being coaxially arranged on the inner side of the sealing flange (510).

6. The cable testing device according to claim 4, characterized in that: The sealing member (500) further comprises a second sealing ring, the second sealing ring being used to be sleeved on the cable to be tested (10), the second sealing ring being clamped between the sealing flange (510) and the outer wall of the first container (100).

7. The cable testing device according to any one of claims 1 to 6, characterized in that: It also comprises a grounding member (400), wherein the grounding member (400) is arranged on the first container (100), and the grounding member (400) is used to be connected to a ground wire so as to ground the first container (100).

8. The cable testing device according to any one of claims 1 to 6, characterized in that: The first container (100) comprises a cover (110) and a container body (120) having an opening, the container body (120) being used to install the cable to be tested (10) and contain a saline solution, and the cover (110) is arranged to cover the opening of the container body (120).

9. A cable testing method, using the cable testing device according to any one of claims 1 to 8, characterized in that: The following steps are involved: Fixing the cable to be tested (10) on a first container (100) in the cable testing device, and adding a saline solution into the first container (100); Adding insulating liquid to a second container (200) in the cable testing device; Transmitting frequency and voltage to the cable to be tested (10) through an electrical signal generator (300) in the cable testing equipment; After the test is completed, the water tree condition on the tested cable (10) is observed and recorded.

10. The testing method according to claim 9, characterized in that: The observing and recording of the water tree condition on the cable (10) to be tested comprises: Taking a plurality of slices from the cable (10) to be tested, and staining each of the slices with a stain to display the water tree; The water tree was observed under a microscope and its parameters were recorded.

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