A high voltage distribution cabinet and its interface device

Abstract

The present invention discloses an interface device for testing outside a high-voltage power distribution cabinet, comprising a U-shaped conductor, wherein the two ends of the U-shaped conductor are two connection ends for connecting a cable shielding wire and a grounding wire respectively, and the outer peripheries of the two connection ends are provided with insulating components, and the U-shaped conductor between the two components is a test section. During the cable partial discharge detection process, the U-shaped conductor is connected to the cable shielding wire, and part of the current in the cable shielding wire flows along the U-shaped conductor to the grounding wire. The tester detects the current size in the U-shaped conductor through a current detection device such as a mutual inductor. When the cable performance deteriorates, it can be discovered in time, thereby avoiding power accidents. The present invention also provides a high-voltage power distribution cabinet including the above-mentioned interface device, and has the above-mentioned advantages.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power testing equipment, and in particular to an interface device. The present invention also relates to a high-voltage power distribution cabinet comprising the interface device. Background Art

[0002] Insulation is of great significance to the normal operation and life of power cables. The amount of partial discharge can characterize the insulation performance of power cables and predict the changing trend of power cable insulation. For power cables with excessive partial discharge, if no measures are taken, it may lead to insulation degradation and accelerate the insulation damage process. In order to determine the amount of partial discharge of power cables, they need to be tested. Partial discharge usually adopts the pulse current detection method. During the detection process, the high-voltage cable shielding wire of the high-voltage distribution cabinet is embedded in the current transformer. By detecting the pulse current in the shielding wire, the amount of partial discharge of the incoming cable can be determined.

[0003] During the cable partial discharge detection process, the high-voltage distribution cabinet door cannot be opened because the equipment is energized. This makes it impossible to detect the measurement point of the high-voltage cable grounding shield line, and the cable's own performance will continue to decline during the detection process. Once the cable's own performance is too low and is not discovered in time, it may cause an electric power accident.

[0004] Therefore, how to detect the performance of the cable itself during the cable partial discharge detection process is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] The object of the present invention is to provide an interface device, which is connected to the cable shielding wire through a U-shaped conductor, draws the current out of the high-voltage distribution cabinet, and then detects the current through a current detection device, thereby realizing the detection of the cable's own performance during the cable partial discharge detection process. Another object of the present invention is to provide a high-voltage distribution cabinet including the above-mentioned interface device.

[0006] To achieve the above-mentioned purpose, the present invention provides an interface device for testing outside a high-voltage distribution cabinet, comprising a U-shaped conductor, wherein the two ends of the U-shaped conductor are respectively used to connect the cable shielding wire and the grounding wire. The outer peripheries of the two connection ends are provided with insulating components, and the U-shaped conductor between the two components is a test section.

[0007] Preferably, the insulating assembly includes a first insulating member fixedly connected to the U-shaped conductor and a second insulating member connected to a cabinet.

[0008] Preferably, the first insulating member and the second insulating member are plugged and fixed.

[0009] Preferably, the first insulating member includes a plug-in portion located at the front and an insulating member body located at the rear, both of which are cylindrical and coaxially arranged, the diameter of the plug-in portion is smaller than the diameter of the insulating member body, and the first insulating member has a first through hole that penetrates axially for connecting to the U-shaped conductor.

[0010] Preferably, the second insulating member is cylindrical and has an inserting groove extending axially for inserting and cooperating with the inserting portion, and the bottom of the inserting groove has a second through hole penetrating axially for the U-shaped conductor to pass through.

[0011] Preferably, an insulating layer is provided on the periphery of the test section.

[0012] The present invention also provides a high-voltage power distribution cabinet, comprising any one of the above-mentioned interface devices.

[0013] Preferably, it comprises a cabinet body, in which a cable shielding wire connected to the inner shielding layer of the high-voltage cable and a grounding wire for grounding the interface device are arranged, and the cable shielding wire and the grounding wire are respectively connected to the two connecting ends.

[0014] The interface device provided by the present invention is used for testing outside a high-voltage distribution cabinet, and includes a U-shaped conductor. The two ends of the U-shaped conductor are connection ends for connecting a cable shielding wire and a grounding wire respectively. Insulation components are provided on the periphery of the two connection ends, and the U-shaped conductor between the two components is a test section.

[0015] During the cable partial discharge test, the U-shaped conductor is connected to the cable shield, and part of the current in the cable shield flows along the U-shaped conductor to the ground wire. The tester detects the current in the U-shaped conductor through current detection devices such as mutual inductors. When the cable performance deteriorates, it can be discovered in time to avoid power accidents.

[0016] The present invention also provides a high-voltage power distribution cabinet including the above-mentioned interface device and having the above-mentioned advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0018] Figure 1 A schematic diagram of the structure of the interface device provided by the present invention;

[0019] Figure 2 for Figure 1 A schematic structural diagram of the first insulating member;

[0020] Figure 3 for Figure 1 A schematic structural diagram of the second insulating member;

[0021] Figure 4 for Figure 1 Schematic diagram of the structure of the middle interface device installed in the high-voltage distribution cabinet.

[0022] in, Figures 1 to 4 The reference numerals in the drawings are:

[0023] U-shaped conductor 1, first insulating member 2, second insulating member 3, connecting end 4, cable shielding wire 5, grounding wire 6, cabinet 7, first through hole 21, plug-in portion 22, plug-in slot 31, second through hole 32. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0026] Please refer to Figures 1 to 4 , Figure 1 A schematic diagram of the structure of the interface device provided by the present invention; Figure 2 for Figure 1 A schematic structural diagram of the first insulating member; Figure 3 for Figure 1 A schematic structural diagram of the second insulating member; Figure 4 for Figure 1 Schematic diagram of the structure of the middle interface device installed in the high-voltage distribution cabinet.

[0027] The interface device provided by the present invention is used for testing outside a high-voltage power distribution cabinet. Figure 1As shown, the interface device includes a U-shaped conductor 1 and an insulating component. The two ends of the U-shaped conductor 1 are connection ends 4 and connection ends 4, which are inserted into the cabinet 7 and connected to the circuit in the cabinet 7. The two connection ends 4 are used to connect the cable shielding wire 5 and the grounding wire 6 respectively. The current in the cable shielding wire 5 flows to the grounding wire 6 through the U-shaped conductor 1, and the tester measures the current in the U-shaped conductor 1 through a current detection device such as a mutual inductor. Specifically, the tester uses a clamp-type current detection device to measure the current. The clamp-type current detection device uses the high-frequency pulse current detection principle to detect the operating status of the high-voltage cable, which can timely avoid power accidents caused by the degradation of the cable's own performance, and can detect partial discharge of the cable without power outages.

[0028] In addition, to ensure the safety of personnel and equipment, the outer peripheries of the two connection ends 4 are provided with insulating components, and the U-shaped conductor 1 is wrapped in the insulating components. The U-shaped conductor 1 between the two insulating components is a test section for current testing. In order to prevent the tester from contacting the test section and getting an electric shock, the outer periphery of the test section can be coated with materials such as insulating paint to form an insulating layer. In a specific embodiment of the present application, the U-shaped conductor 1 is a U-shaped copper rod. The length of the U-shaped copper rod exposed outside the cabinet 7 is greater than 30 mm, the length of the U-shaped copper rod between the two insulating components is more than 70 mm, and the diameter of the U-shaped copper rod should be more than 5.5 mm. Of course, users can also use conductors of other materials, and the sizes of the U-shaped conductor 1 and the insulating components can also be set as needed, which is not limited here. The second periphery is provided with external threads. When in use, the two connection ends 4 are inserted into the cabinet 7 and are respectively connected to the cable shielding wire 5 and the grounding wire 6 through nuts.

[0029] Optionally, the insulating assembly includes a first insulating member 2 and a second insulating member 3. The first insulating member 2 is fixedly connected to the U-shaped conductor 1, and the second insulating member 3 is connected to the cabinet 7 of the high-voltage power distribution cabinet. The first insulating member 2 and the second insulating member 3 are fixed by plugging, and the insulation between the U-shaped conductor 1 and the cabinet 7 is achieved by the insulating assembly.

[0030] Optional, such as Figure 2 As shown, the first insulating member 2 includes an insulating member body and a plug-in portion 22, and the front end of the insulating member body is connected to the rear end of the plug-in portion 22. Both are cylindrical and coaxially arranged, and the diameter of the plug-in portion 22 is smaller than the diameter of the insulating member body, so that a first step surface is formed at the front end of the insulating member body. The first insulating member 2 has a first through hole 21 that passes through the axial direction, and the U-shaped conductor 1 is fixed in the first through hole 21. In order to improve the connection strength between the first insulating member 2 and the U-shaped conductor 1, the first insulating member 2 can be made of plastic material and is arranged on the outer periphery of the U-shaped conductor 1 by casting.

[0031] Optional, such as Figure 3As shown, the second insulating member 3 is cylindrical and has an axially extending insertion groove 31, the inner diameter of the insertion groove 31 is equal to the outer diameter of the insertion portion 22, the depth of the insertion groove 31 is equal to the length of the insertion portion 22, and the two are plugged together. The bottom of the insertion groove 31 has a second through hole 32 that penetrates along the axial direction, and the connection end 4 of the U-shaped conductor 1 passes through the second through hole 32.

[0032] Optionally, the outer diameters of the insulating member body and the second insulating member 3 are equal and both are above 30 mm. The diameter of the plug-in portion 22 is above 12 mm. The second insulating member 3 is fixed to the cabinet 7 by gaskets and bolts. Specifically, the rear end face of the second insulating member 3 is connected to the cabinet 7, and the rear end face is the end face of the second insulating member 3 away from the first insulating member 2. Of course, the user can also connect the front end face of the second insulating member 3 or the middle part of the second insulating member 3 to the cabinet 7 as needed, which is not limited here. In addition, the first insulating member 2 and the second insulating member 3 can also adopt other shapes such as rectangular and hexagonal cross-sections, not limited to cylindrical cross-sections. The length of the two connecting ends 4 inserted into the cabinet 7 is above 30 mm, and the external threads of the two extend into the second through hole 32. The two connecting ends 4 are fixed in the cabinet 7 by nuts, and the first insulating member 2 is against the second insulating member 3 outside the cabinet 7, thereby fixing the U-shaped conductor 1.

[0033] In this embodiment, the interface device is connected to the cable shielding wire 5 through the U-shaped conductor 1, and the current of the cable shielding wire 5 is led out of the cabinet 7. Then, the current detection device detects the current change in the cable shielding wire 5, and the performance degradation of the cable can be discovered in time to avoid power accidents. In addition, an insulating component is also provided on the periphery of the U-shaped conductor 1 to prevent the tester from electric shock.

[0034] The present invention also provides a high-voltage power distribution cabinet, including any one of the above-mentioned interface devices. Specifically, the high-voltage power distribution cabinet includes a cabinet body 7, and a cable shielding wire 5 and a grounding wire 6 for connecting the inner shielding layer of the high-voltage cable are provided in the cabinet body 7. The cable shielding wire 5 is connected to one connection end 4, and the grounding wire 6 is connected to the other connection end 4. The current in the inner shielding layer of the cable flows along the U-shaped conductor 1 to the grounding wire 6. The tester can detect the current in the U-shaped conductor 1 through the current detection device, and then judge the performance of the cable. The structure of other parts of the high-voltage power distribution cabinet can refer to the prior art and will not be repeated here. It should be noted that the interface device provided in the present application can also be applied to cabinets 7 such as high-voltage switch cabinets, cable junction boxes, and box-type transformers, and is not limited to high-voltage power distribution cabinets.

[0035] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0036] The high-voltage power distribution cabinet and its interface device provided by the present invention are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. An interface device for testing outside a high-voltage distribution cabinet, characterized in that: It comprises a U-shaped conductor (1), the two ends of the U-shaped conductor (1) are two connection ends (4) respectively used to connect a cable shielding wire (5) and a grounding wire (6), the outer peripheries of the two connection ends (4) are both provided with insulating components, and the U-shaped conductor (1) between the two components is a test section; The insulating assembly comprises a first insulating member (2) fixedly connected to the U-shaped conductor (1) and a second insulating member (3) connected to a cabinet (7), wherein the first insulating member (2) and the second insulating member (3) are plugged and fixed; The first insulating member (2) comprises a plug-in portion (22) at the front and an insulating member body at the rear, both of which are cylindrical and coaxially arranged, the plug-in portion (22) has a diameter smaller than the diameter of the insulating member body, and the first insulating member (2) has a first through hole (21) penetrating along the axial direction and used to connect with the U-shaped conductor (1); The second insulating member (3) is cylindrical and has an insertion groove (31) extending along the axial direction for inserting and matching with the insertion portion (22). The bottom of the insertion groove (31) has a second through hole (32) penetrating along the axial direction for allowing the U-shaped conductor (1) to pass through.

2. The interface device according to claim 1, characterized in that: An insulating layer is provided on the periphery of the test section.

3. A high voltage distribution cabinet, characterized in that: The interface device comprises any one of claims 1 to 2.

4. The high voltage distribution cabinet according to claim 3, characterized in that: The invention comprises a cabinet (7), wherein a cable shielding wire (5) for connecting to the inner shielding layer of a high-voltage cable and a grounding wire (6) for grounding the interface device are arranged in the cabinet (7), and the cable shielding wire (5) and the grounding wire (6) are respectively connected to the two connection ends.

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