Wire immersion voltage withstand test method and system for blocking diffusion of spark breakdown channel

Abstract

The invention provides a wire immersion voltage withstand test method and test system for blocking spark breakdown channel diffusion. The test system comprises a water bath; a withstand voltage test control system; and the I-shaped wire loading disc is wound with a to-be-tested wire and then is placed in the water bath. The withstand voltage test control system is connected with the electric wire and then carries out an immersion withstand voltage test. A to-be-tested wire is subjected to pre-segmentation planning according to the length, the wire is wound in a layer-by-layer winding mode, when the wire is wound to the planned segmentation length, the surface of the wound part of the wire is coated with a layer of flexible composite belt, and the width of the flexible composite belt is consistent with the length of a spool of an I-shaped wire loading disc; therefore, an independent space is formed through coating of the flexible composite belt, and then winding and coating of the flexible composite belt are continued until winding is completed, so that the whole to-be-tested wire is divided into a plurality of relatively independent spaces by the flexible composite belt, a breakdown channel of a breakdown point is prevented from diffusing towards an adjacent layer on a wire shaft in a test, and the adjacent layer wire is protected from being damaged.

Description

Technical Field

[0001] The present invention relates to the technical field of wire and cable testing, in particular to a water immersion test, and more specifically to a wire water immersion withstand voltage test method and system for blocking the diffusion of spark breakdown channels. Background Art

[0002] In the existing technology, wires and cables used in special scenarios such as satellites, nuclear power plants, polar regions and other extreme application conditions need to undergo normal electrical performance tests (such as conductor resistance, insulation, etc.) and appearance and mechanical performance tests (such as outer diameter, weight, degree of cross-linking, tensile strength, elongation at break, etc.). In addition, they also need to undergo water immersion voltage withstand tests to conduct secondary screening of the wires and cables and further ensure the quality of the wire and cable products.

[0003] Wires used in special scenarios, especially small-sized cables designed for lightweight requirements, are light in weight and small in cross-sectional area. They have stringent requirements on indicators such as conductor resistance, outer diameter and weight. Therefore, their insulation thickness is strictly designed and produced according to the standard voltage resistance level. If a breakdown occurs due to a tiny insulation defect at a certain point during the immersion voltage test, a spark breakdown channel (space) will be formed between the conductor and the liquid, which will cause the wires in the spark breakdown channel (space) on the spool to lose their insulation properties due to scorching. During the testing and screening process, it was found that if the breakdown channel is not blocked, it will instantly spread to the surroundings, scorching the wires in the channel (space), causing intermittent damage to the wires on the entire spool, and they can only be scrapped. Summary of the invention

[0004] In view of the defects and shortcomings of the prior art, the purpose of the present invention is to provide a wire immersion voltage withstand test method and test system for blocking the spread of spark breakdown channels, so as to solve the problem of large-area scorching of adjacent layers on the spool caused by breakdown due to insulation defects at a certain point during the cable immersion test. The method of the present invention can block the breakdown channel from spreading to the adjacent layers of wires on the spool, thereby protecting the adjacent layers of wires from damage.

[0005] According to a first aspect of the present invention, a method for testing the water-immersion withstand voltage of a wire for blocking the diffusion of a spark breakdown channel is provided, comprising the following steps:

[0006] Step 1, winding a wire to be tested onto an I-shaped wire drum in a layer-by-layer winding manner, wherein: the wire to be tested is pre-planned in sections according to its length; during the cable winding process, when the wire is wound to the planned section length, a layer of flexible composite tape is coated on the surface of the wire that has been wound, and the width of the flexible composite tape is consistent with the length of the I-shaped wire drum spool, thereby forming an independent space through the coating of the flexible composite tape, and then the winding and the coating of the flexible composite tape are continued until the winding is completed, so that the entire wire to be tested is divided into a plurality of relatively independent spaces by the flexible composite tape;

[0007] Step 2: Extend the inner and outer ends of the wire out of the spool through the outlet holes designed on the side panels of the I-shaped wire reel, put them into a water bath, and connect them to the withstand voltage test control system for immersion withstand voltage test.

[0008] As an optional implementation, during the coiling process, the wire to be tested is pre-segmented according to its length, layered into N segments, and wrapped with N-1 flexible composite tapes, so that each segment of the wire separated by the flexible composite tape forms N independent spaces after coiling.

[0009] As an optional implementation, during the water immersion pressure test, when breakdown occurs in any section, the flexible composite tape is used to block the diffusion of the breakdown channel to the adjacent layer, thereby controlling the spark breakdown and scorching range.

[0010] According to a second aspect of the present invention, a wire immersion withstand voltage test system for blocking the diffusion of spark breakdown channels is provided, comprising:

[0011] Water bath;

[0012] Hipot test control system; and

[0013] An I-shaped wire drum, which is placed in the water bath after winding the wire to be tested;

[0014] Wherein, the withstand voltage test control system is connected to the wire to be tested and then a water immersion withstand voltage test is performed;

[0015] In addition, the wire to be tested is pre-segmented according to its length, and the wire to be tested is arranged to be wound onto an I-shaped wire reel in the following manner: the wire is wound layer by layer, and when the wire is wound to the planned segmented length, a layer of flexible composite tape is coated on the surface of the wound wire portion, and the width of the flexible composite tape is consistent with the length of the I-shaped wire reel spool, thereby forming an independent space through the coating of the flexible composite tape, and then the winding and the coating of the flexible composite tape are continued until the winding is completed, so that the entire wire to be tested is divided into a plurality of relatively independent spaces by the flexible composite tape.

[0016] As an optional embodiment, the flexible composite tape is a fluoroplastic flexible film tape, and the upper and lower surfaces of the flexible film tape are textured so that the flexible composite tape and the wire flow smoothly during the water immersion pressure test;

[0017] Furthermore, the side edge of the flexible composite belt is designed to be serrated, so that the flexible composite belt and the inner side of the side plate of the I-shaped wiring reel form a flow channel allowing liquid to flow.

[0018] It should be understood that all combinations of the aforementioned concepts and the additional concepts described in more detail below can be considered as part of the inventive subject matter of the present disclosure as long as such concepts are not mutually inconsistent. In addition, all combinations of the claimed subject matter are considered as part of the inventive subject matter of the present disclosure.

[0019] The foregoing and other aspects, embodiments and features of the present invention can be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the present invention, such as the features and / or beneficial effects of the exemplary embodiments, will be apparent from the following description or learned from the practice of the specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are not intended to be drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in each figure may be represented by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings.

[0021] Figure 1 Schematic diagram of a wire water immersion withstand voltage test system according to an embodiment of the present invention.

[0022] Figure 2 Schematic diagram of an I-shaped cable tray according to an embodiment of the present invention.

[0023] Figure 3 Schematic diagram of a cross-section of wire winding according to an embodiment of the present invention.

[0024] Figure 4 is a schematic diagram of a flexible composite tape according to an embodiment of the present invention.

[0025] Figure 5 Schematic diagram of flexible composite tape wrapping according to an embodiment of the present invention.

[0026] Figure 6 Schematic diagram of using a flexible composite tape to cover an electric wire according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to better understand the technical content of the present invention, specific embodiments are given and described as follows in conjunction with the accompanying drawings.

[0028] Various aspects of the present invention are described in this disclosure with reference to the accompanying drawings, in which many illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to include all aspects of the present invention. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed by the present invention are not limited to any implementation. In addition, some aspects disclosed by the present invention can be used alone or in any appropriate combination with other aspects disclosed by the present invention.

[0029] {Example 1}

[0030] Combination Figure 1-6 In the example shown, a wire immersion withstand voltage test system for blocking the spread of spark breakdown channels according to an embodiment of the present invention includes a water bath 100 , a withstand voltage test control system 200 , and an I-shaped wire drum 300 for winding the wire 1 .

[0031] As shown in the accompanying drawings, the I-shaped wire reel 300 is placed in a water bath 100 after winding the wire 1 to be tested. The depth and height of the water bath are designed to accommodate the I-shaped wire reel 300 for water immersion and withstand voltage, and reliable grounding is done through the grounding wire as shown in the figure to ensure the safety of the withstand voltage test process.

[0032] Combination Figure 1 As shown, the withstand voltage test control system 200 and the wire to be tested are subjected to a water immersion withstand voltage test.

[0033] As an optional embodiment, the withstand voltage test control system 200 can use commercial high-voltage test equipment, whose voltage range is selected according to the characteristics of the test wire, and the test voltage level as an example is higher than 10kV. In addition, the withstand voltage test equipment ensures reliable grounding through grounding measures. The test can be selected at either power frequency or high frequency, and the output test voltage error value is less than ±0.1% to test whether the wire meets the test standards and requirements.

[0034] In an embodiment of the present invention, combined with Figures 2 to 6 As shown, the wire to be tested 1 is pre-segmented according to its length, and the wire to be tested is arranged to be wound onto the I-shaped wire drum 300 in the following manner: the wire is wound layer by layer, and when the wire is wound to the planned segmented length, a layer of flexible composite tape 320 is coated on the surface of the wound wire portion, and the width of the flexible composite tape is consistent with the length of the bobbin 311 of the I-shaped wire drum 300, thereby forming an independent space through the coating of the flexible composite tape 320, and then the winding and the coating of the flexible composite tape are continued until the winding is completed, so that the entire wire to be tested is divided into a plurality of relatively independent spaces by the flexible composite tape.

[0035] As an optional implementation, the I-shaped cable tray 300 can be made of engineering plastics, which has excellent processing performance, smooth surface and high mechanical strength, and has a certain load-bearing capacity, usually not less than 30kg. Figure 2 The design of the I-shaped cable drum 300 is shown as an example, including a cylindrical bobbin 311 and side plates 312 on both sides of the length direction of the bobbin 311, forming an integrated structure. At least one side plate 312 of the bobbin is designed with two "0" wire outlet holes 313 along the diameter direction of the cylinder, the width of which is greater than the outer diameter of the wire, for the inner and outer ends of the wire to extend out of the bobbin and connect to the withstand voltage test control system for immersion withstand voltage test.

[0036] Combination Figure 2 , 3 As shown, the electric wire 1 is wound around the bobbin 311 of the I-shaped wire drum 300 in a layer-by-layer winding manner. Figure 3 A schematic cross-sectional view of a winding drum is shown. For the winding process of the electric wire 1, a composite tape of appropriate width is placed in the wire drum for winding the electric wire.

[0037] In combination with the above embodiments, during the coiling process, the wire to be tested is pre-segmented according to its length, divided into N segments, and wrapped with N-1 flexible composite tapes 320, so that each segment of the wire separated by the flexible composite tape forms N independent spaces after coiling.

[0038] As an example, for a certain length of the wire 1 to be tested, the length is planned according to 3:3:4. When winding to a certain length, a layer of high-voltage resistant soft composite tape is coated to form a relatively independent space; continue to wind a certain length of wire, and then wrap a layer of soft high-voltage resistant composite tape, and then wrap a certain length of wire outside. That is, through two times of coating with high-voltage resistant composite tape, a certain length of wire is isolated into 3 independent spaces.

[0039] Therefore, during the water immersion voltage test, if a breakdown point occurs in the wire due to an insulation defect at a certain place, the high-voltage resistant composite tape will block the breakdown channel from spreading to the adjacent layer, control the range of spark breakdown and scorching, protect the quality of the wires in the adjacent space, and will not cause the entire reel of wires to be scrapped.

[0040] As an optional embodiment, the flexible composite tape 320 uses a high-pressure resistant flexible composite tape, especially a fluoroplastic flexible film tape (such as FEP film). On the one hand, based on the good breakdown field strength of fluoroplastics, the film can block the spark breakdown channel from diffusing to the adjacent layer, thereby protecting the quality of the wires in the adjacent layer on the bobbin; on the other hand, a composite film based on fluoroplastics (such as PTFE) can be used, and the mechanical properties of the fluoroplastic composite film can be improved by compounding the fluoroplastic substrate with reinforcing materials such as glass fiber, so as to facilitate the coating process for operators.

[0041] As an optional embodiment, the thickness of the flexible composite tape 320 is controlled between 0.5 mm and 2 mm.

[0042] As an optional embodiment, the upper and lower surfaces of the flexible composite tape 320 are textured so that the liquid between the flexible composite tape and the wire can flow smoothly during the water immersion voltage test, thereby ensuring the water immersion test effect.

[0043] As an example, combining Figure 4 As shown, the upper and lower surfaces of the flexible composite belt are textured, including: convex point pattern processing, and the height of the convex point 321 is 0.1-0.5 mm.

[0044] It should be understood that the distribution of the protrusions 321 can be designed to be regularly distributed or randomly distributed.

[0045] As an optional embodiment, combining Figure 4 As shown, the side edge of the flexible composite tape 320 is designed to be serrated 322, so that the flexible composite tape and the inner side of the side plate of the I-shaped wiring reel form a flow channel for liquid, thereby ensuring the effect of the immersion test.

[0046] {Example 2}

[0047] Combination Figures 1 to 6 As shown, in combination with the wire immersion voltage withstand test method of the above embodiment, a wire immersion voltage withstand test method for blocking the diffusion of spark breakdown channel is proposed in this embodiment, comprising the following steps:

[0048] Step 1, winding a wire 1 to be tested onto an I-shaped wire drum 300 in a layer-by-layer winding manner, wherein: the wire 1 to be tested is pre-planned in sections according to its length; during the cable winding process, when the wire is wound to the planned section length, a layer of flexible composite tape 320 is coated on the surface of the wire that has been wound, and the width of the flexible composite tape 320 is consistent with the length of the bobbin 311 of the I-shaped wire drum 300, thereby forming an independent space through the coating of the flexible composite tape, and then the winding and the coating of the flexible composite tape are continued until the winding is completed, so that the entire wire to be tested is divided into a plurality of relatively independent spaces by the flexible composite tape;

[0049] Step 2: Extend the inner and outer ends of the wire out of the spool through the outlet holes 313 designed on the side panels of the I-shaped wire reel, put them into the water bath 100, and connect them to the withstand voltage test control system 200 for immersion withstand voltage test.

[0050] In a particularly preferred embodiment, the upper and lower surfaces of the flexible composite tape 320 are textured so that the flexible composite tape and the wires can flow smoothly during the water immersion and pressure resistance test.

[0051] In a particularly preferred embodiment, the side edge of the flexible composite belt is designed to be serrated, so that the flexible composite belt and the inner side of the side plate of the I-shaped wiring reel form a flow channel allowing liquid to flow.

[0052] Therefore, during the water immersion voltage test, if a breakdown point occurs in the wire due to an insulation defect at a certain place, the high-voltage resistant composite tape will block the breakdown channel from spreading to the adjacent layer, control the range of spark breakdown and scorching, protect the quality of the wires in the adjacent space, and will not cause the entire reel of wires to be scrapped.

[0053] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. A method for testing the water-immersion withstand voltage of electric wires for blocking the diffusion of spark breakdown channels, characterized in that: The test method comprises the following steps: Step 1, winding a wire to be tested onto an I-shaped wire drum in a layer-by-layer winding manner, wherein: the wire to be tested is pre-segmented according to its length; during the cable winding process, when the wire is wound to the planned segmented length, a layer of flexible composite tape is coated on the surface of the wire that has been wound, and the width of the flexible composite tape is consistent with the length of the I-shaped wire drum spool, thereby forming an independent space through the coating of the flexible composite tape, and then the winding and the coating of the flexible composite tape are continued until the winding is completed, so that the entire wire to be tested is divided into a plurality of relatively independent spaces by the flexible composite tape; Step 2: Extend the inner and outer ends of the wire out of the spool through the outlet holes designed on the side panels of the I-shaped wire reel, put them into a water bath, and connect them to the withstand voltage test control system for immersion withstand voltage test.

2. The wire immersion withstand voltage test method for blocking the diffusion of spark breakdown channels according to claim 1, characterized in that: The flexible composite belt used is a fluoroplastic flexible film belt.

3. The wire immersion withstand voltage test method for blocking the diffusion of spark breakdown channels according to claim 2, characterized in that: The thickness of the flexible composite belt is controlled between 0.5 mm and 2 mm.

4. The wire immersion withstand voltage test method for blocking the diffusion of spark breakdown channels according to claim 2, characterized in that: The upper and lower surfaces of the flexible composite tape are textured so that the flexible composite tape and the wire can flow smoothly during the water immersion and pressure resistance test.

5. The wire immersion withstand voltage test method for blocking the diffusion of spark breakdown channels according to claim 4, characterized in that: The upper and lower surfaces of the flexible composite belt are textured, including convex point pattern processing, and the height of the convex points is 0.1-0.5 mm.

6. The wire immersion withstand voltage test method for blocking the diffusion of spark breakdown channels according to claim 4, characterized in that: The side edge of the flexible composite belt is designed to be serrated, so that the flexible composite belt and the inner side of the side plate of the I-shaped wiring reel form a flow channel allowing liquid to flow.

7. The method for testing the water-immersion withstand voltage of electric wires for blocking the diffusion of spark breakdown channels according to any one of claims 1 to 6, characterized in that: During the coiling process, the wire to be tested is pre-segmented according to its length, layered into N segments, and wrapped with N-1 flexible composite tapes, so that each segment of the wire separated by the flexible composite tape forms N independent spaces after coiling.

8. The method for testing the water-immersion withstand voltage of electric wires for blocking the diffusion of spark breakdown channels according to claim 7, characterized in that: During the water immersion pressure test, when breakdown occurs in any section, the flexible composite tape is used to block the diffusion of the breakdown channel to the adjacent layer, thereby controlling the scope of spark breakdown and scorching.

9. A wire immersion withstand voltage test system for blocking the diffusion of spark breakdown channels, characterized in that: include: Water bath; Withstand voltage test control system; as well as An I-shaped wire drum, which is placed in the water bath after winding the wire to be tested; Wherein, the withstand voltage test control system is connected to the wire to be tested and then a water immersion withstand voltage test is performed; In addition, the wire to be tested is pre-segmented according to its length, and the wire to be tested is arranged to be wound onto an I-shaped wire reel in the following manner: the wire is wound layer by layer, and when the wire is wound to the planned segmented length, a layer of flexible composite tape is coated on the surface of the wound wire portion, and the width of the flexible composite tape is consistent with the length of the I-shaped wire reel spool, thereby forming an independent space through the coating of the flexible composite tape, and then the winding and the coating of the flexible composite tape are continued until the winding is completed, so that the entire wire to be tested is divided into a plurality of relatively independent spaces by the flexible composite tape.

10. The wire immersion withstand voltage test system for blocking the diffusion of spark breakdown channels according to claim 9, characterized in that: The flexible composite tape is a fluoroplastic flexible film tape, and the upper and lower surfaces of the flexible film tape are textured so that the flexible composite tape and the wire can flow smoothly during the water immersion and pressure resistance test; Furthermore, the side edge of the flexible composite belt is designed to be serrated, so that the flexible composite belt and the inner side of the side plate of the I-shaped wiring reel form a flow channel allowing liquid to flow.

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