High-voltage cable grounding ring current resistance type current limiting device based on novel structure

Abstract

The utility model relates to a high-voltage cable grounding ring current resistance type current limiting device based on a novel structure, which comprises a cabinet body and a current limiting system, the current limiting system is arranged in the cabinet body, two door plates are symmetrically arranged on the front surface of the cabinet body, the two door plates are connected with the side edges of the cabinet body through hinges, and a left side plate, a right side plate and a bottom plate of the cabinet body are provided with heat dissipation holes. The current limiting system comprises a supporting plate, a base, an A-phase resistor module, an A-phase metal sliding rail, a B-phase resistor module, a B-phase metal sliding rail, a C-phase resistor module and a C-phase metal sliding rail. The A-phase resistor module and the A-phase metal sliding rail work in a matched mode, the B-phase resistor module and the B-phase metal sliding rail work in a matched mode, and the C-phase resistor module and the C-phase metal sliding rail work in a matched mode. And the maintenance is easy after operation.

Description

Technical Field

[0001] The utility model belongs to the technical field of cable grounding, in particular to a high-voltage cable grounding loop current resistor type current limiting device based on a new structure. Background Art

[0002] In order to reduce the induced voltage on the sheath of a single-core high-voltage cable so that it is not too large, the cable sheath must be grounded in sections during the project to limit the size of the induced voltage. However, if the grounding method is improper, this induced voltage will form a large grounding current on the metal sheath, which will bring two major hazards to the cable transmission line: one is to greatly reduce the ability of the cable to transmit electricity (about one-third), and the other is to cause the metal sheath to heat up and reduce the main insulation, shortening the normal operation life of the cable. Therefore, the metal sheath of the high-voltage cable must adopt the correct grounding method to ensure that the circulating current is minimized and meet the normal operation requirements.

[0003] At present, in order to limit the circulating current of the metal sheath of the high-voltage single-core power cable line, the three-phase metal sheath cross-interconnection grounding method is usually adopted. The cross-interconnection grounding method refers to dividing the long cable line into three sections evenly, and each section is cross-connected through coaxial cable and cross-interconnection box. Because the phase difference of the three-phase cable core current is 120°, the phase difference of the induced voltage of the metal sheath is also 120°. After the vector addition, the induced voltage of the three sections of the metal sheath after cross-interconnection is a very small value. Therefore, the induced voltage on the metal sheath of the cable can be suppressed by the cross-interconnection grounding method, thereby suppressing the grounding loop current of the metal sheath. However, due to poor installation quality or large transmission capacity, there will still be a large circulating current in the cable line cross-interconnection system.

[0004] Traditional circulation suppression devices have the disadvantages of complex structure, inconvenient installation, and heavy maintenance workload after operation. Utility Model Content

[0005] The purpose of the utility model is to overcome the shortcomings of the prior art and propose a high-voltage cable grounding loop current limiting device based on a new structure.

[0006] The utility model solves the technical problem by adopting the following technical solutions:

[0007] A high-voltage cable grounding loop current resistor type current limiting device based on a new structure includes a cabinet and a current limiting system. The current limiting system is installed inside the cabinet. Two door panels are symmetrically arranged on the front of the cabinet. The two door panels are connected to the sides of the cabinet through hinges. The left side panel, right side panel and bottom plate of the cabinet are provided with heat dissipation holes.

[0008] Moreover, the heat dissipation holes are respectively arranged on the left side plate, the right side plate and the bottom of the cabinet body for air convection.

[0009] Moreover, the current limiting system includes a support plate, a base, an A-phase resistor module, an A-phase metal slide rail, a B-phase resistor module, a B-phase metal slide rail, a C-phase resistor module and a C-phase metal slide rail, wherein the base is installed at an internal central position, the support plate is installed above the base, the A-phase resistor module, the B-phase resistor module and the C-phase resistor module are fixed to the support plate through support insulators, the A-phase metal slide rail is installed below the A-phase resistor module and fixed to the support plate through support insulators, the B-phase metal slide rail is installed below the B-phase resistor module and fixed to the support plate through support insulators, and the C-phase metal slide rail is installed below the C-phase resistor module and fixed to the support plate through support insulators.

[0010] Moreover, the A-phase resistance module, the B-phase resistance module and the C-phase resistance module have the same structure, and the A-phase metal slide rail, the B-phase metal slide rail and the C-phase metal slide rail have the same structure.

[0011] Moreover, the A-phase resistance module includes an internal circuit and 6 extending terminals, and the 6 terminals are terminal 0, terminal 1, terminal 2, terminal 3, terminal 4 and terminal 5 respectively.

[0012] Moreover, the internal circuit includes chip resistor unit No. 1, chip resistor unit No. 2, chip resistor unit No. 3, chip resistor unit No. 4 and chip resistor unit No. 5, chip resistor unit No. 5, chip resistor unit No. 4, chip resistor unit No. 3, chip resistor unit No. 2 and chip resistor unit No. 1 are connected in sequence through wires, and chip resistor units No. 1, 2, 3, 4, and 5 are respectively placed at terminals No. 1, 2, 3, 4, and 5, and the other end of chip resistor unit No. 1 is placed at terminal No. 0, and terminal No. 0 is grounded.

[0013] Moreover, the chip resistor unit No. 1, chip resistor unit No. 2, chip resistor unit No. 3, chip resistor unit No. 4 and chip resistor unit No. 5 have the same structure, chip resistor units No. 1, 2, 3, 4 and 5 are fixed by four insulating connecting rods, and chip resistor units No. 1, 2, 3, 4 and 5 are isolated by insulating gaskets.

[0014] Moreover, the A-phase metal slide rail includes a slide rail shell and a slider arranged inside thereof, three slide rail grooves are opened on the surface of the slide rail shell, and the slider respectively extends terminals upward: one wiring terminal and two fixed ends, one wiring terminal and two fixed ends are in a mountain shape, and are respectively inserted into the three slide rail grooves opened on the surface of the slide rail shell, and the fixed end is provided with a thread, which is fixed by tightening screws, so that the relative position of the slider and the slide rail shell is fixed, and the slider wiring terminal is in contact with the resistor module wiring terminal.

[0015] The advantages and positive effects of the utility model are:

[0016] 1. The utility model includes a cabinet and a current limiting system, wherein the current limiting system is installed inside the cabinet, and two door panels are symmetrically arranged on the front of the cabinet, and the two door panels are connected to the sides of the cabinet through hinges. The left side panel, the right side panel and the bottom panel of the cabinet are provided with heat dissipation holes, and the current limiting system includes a support plate, a base, an A-phase resistor module, an A-phase metal slide rail, a B-phase resistor module, a B-phase metal slide rail, a C-phase resistor module and a C-phase metal slide rail. The A-phase resistor module and the A-phase metal slide rail work in coordination, the B-phase resistor module and the B-phase metal slide rail work in coordination, and the C-phase resistor module and the C-phase metal slide rail work in coordination. The structural design of the utility model is based on actual on-site applications. In actual use, the device is connected in series to the A, B, and C three-phase grounding system, and has the characteristics of simple structure, convenient installation, and easy maintenance after operation.

[0017] 2. The utility model adopts the cooperation of the A-phase resistance module and the A-phase metal slide rail, the cooperation of the B-phase resistance module and the B-phase metal slide rail, and the cooperation of the C-phase resistance module and the C-phase metal slide rail. The resistance value is changed by connecting different wiring terminals of the resistance module through the metal slide rail. The structure is simple and the connection is reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural diagram of the cabinet of the utility model;

[0019] Figure 2 This is the front view of the current limiting system of the utility model;

[0020] Figure 3 It is a top view of the current limiting system of the utility model;

[0021] Figure 4 It is a structural diagram of the resistance module unit of the utility model;

[0022] Figure 5 It is a structural diagram of the metal slide rail of the utility model;

[0023] Figure 6 It is the principle diagram of the resistance module of the utility model;

[0024] Figure 7 It is a structural principle diagram of the utility model. DETAILED DESCRIPTION

[0025] The utility model is further described in detail below with reference to the accompanying drawings.

[0026] High voltage cable grounding loop current limiting device based on new structure, such as Figure 7 As shown, the device is connected in series to the A, B, C three-phase grounding system and has the characteristics of simple structure, convenient installation and easy maintenance after operation.

[0027] The utility model includes a cabinet and a current limiting system, wherein the current limiting system is installed inside the cabinet. Figure 1 As shown, two door panels are symmetrically arranged on the front of the cabinet, and the two door panels are connected to the sides of the cabinet through hinges. The left side panel, the right side panel and the bottom panel of the cabinet are provided with heat dissipation holes.

[0028] The heat dissipation holes are respectively arranged on the left side plate, the right side plate and the bottom plate of the cabinet body for air convection.

[0029] like Figure 2 As shown, the current limiting system includes a support plate, a base, an A-phase resistor module, an A-phase metal slide rail, a B-phase resistor module, a B-phase metal slide rail, a C-phase resistor module and a C-phase metal slide rail, wherein the base is installed at an internal central position, the support plate is installed above the base, the A-phase resistor module, the B-phase resistor module and the C-phase resistor module are fixed to the support plate through support insulators, the A-phase metal slide rail is installed below the A-phase resistor module and fixed to the support plate through support insulators, the B-phase metal slide rail is installed below the B-phase resistor module and fixed to the support plate through support insulators, and the C-phase metal slide rail is installed below the C-phase resistor module and fixed to the support plate through support insulators.

[0030] The A-phase resistance module, the B-phase resistance module and the C-phase resistance module have the same structure, and the A-phase metal slide rail, the B-phase metal slide rail and the C-phase metal slide rail have the same structure.

[0031] like Figure 3 As shown, the A-phase resistance module includes an internal circuit and six extended terminals, and the six terminals are terminal 0, terminal 1, terminal 2, terminal 3, terminal 4 and terminal 5.

[0032] like Figure 4 As shown, the internal circuit includes chip resistor unit No. 1, chip resistor unit No. 2, chip resistor unit No. 3, chip resistor unit No. 4 and chip resistor unit No. 5, chip resistor unit No. 5, chip resistor unit No. 4, chip resistor unit No. 3, chip resistor unit No. 2 and chip resistor unit No. 1 are connected in sequence through wires, and chip resistor units No. 1, 2, 3, 4, 5 are respectively placed at terminals No. 1, 2, 3, 4, 5, and the other end of chip resistor unit No. 1 is placed at terminal No. 0, and terminal No. 0 is grounded.

[0033] The chip resistor unit No. 1, the chip resistor unit No. 2, the chip resistor unit No. 3, the chip resistor unit No. 4 and the chip resistor unit No. 5 have the same structure, the chip resistor units No. 1, 2, 3, 4 and 5 are fixed by four insulating connecting rods, and the chip resistor units No. 1, 2, 3, 4 and 5 are isolated by insulating gaskets.

[0034] like Figure 5As shown, the A-phase metal slide rail includes a slide rail housing and a slider arranged inside the slide rail housing. Three slide rail grooves are opened on the surface of the slide rail housing. The sliders respectively extend terminals upward: one wiring terminal and two fixed terminals. One wiring terminal and two fixed terminals are in a mountain shape and are respectively inserted into the three slide rail grooves opened on the surface of the slide rail housing. The fixed terminals are provided with threads and are fixed by tightening screws, thereby fixing the relative positions of the slider and the slide rail housing. The wiring terminals of the slider are in contact with the wiring terminals of the resistor module.

[0035] like Figure 6 As shown, chip resistor unit No. 5, chip resistor unit No. 4, chip resistor unit No. 3, chip resistor unit No. 2 and chip resistor unit No. 1 are connected in sequence through wires, and chip resistor units No. 1, 2, 3, 4, and 5 are respectively placed at terminals No. 1, 2, 3, 4, and 5, and the other end of chip resistor unit No. 1 is placed at terminal No. 0, and terminal No. 0 is grounded.

[0036] The working process of the utility model is:

[0037] The resistance value of the device is controlled at 1 ohm during normal operation. When the current of the grounding system exceeds 10A, the resistance value adjustment mode is started, and the resistance value of the cross-connected grounding system of the access cable is adjusted through the resistance value adjustment metal slide rail to increase the resistance value (adjustment range 0Ω, 1Ω, 2Ω, 3Ω, 4Ω, 5Ω). Otherwise, the resistance value is reduced.

[0038] The current values ​​corresponding to different resistance values, the test data are as follows

[0039]

[0040] It can be seen from the test data in the table that with the increase of the access resistance, the ABC three-phase current values ​​in the grounding system all decrease significantly, indicating that the application of the device of the utility model reduces the three-phase current value in the grounding system.

[0041] It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive. Therefore, the present invention includes but is not limited to the embodiments described in the specific implementation manner. Any other implementation manners derived by those skilled in the art based on the technical solution of the present invention also fall within the scope of protection of the present invention.

Claims

1. A high voltage cable grounding loop current limiting device based on a new structure, characterized by: The cabinet comprises a cabinet body and a current limiting system, wherein the current limiting system is installed inside the cabinet body, two door panels are symmetrically arranged on the front of the cabinet body, the two door panels are connected to the sides of the cabinet body through hinges, and heat dissipation holes are opened on the left side panel, the right side panel and the bottom panel of the cabinet body.

2. The high-voltage cable grounding loop current limiting device based on a novel structure according to claim 1 is characterized in that: The heat dissipation holes are respectively arranged on the left side plate, the right side plate and the bottom of the cabinet body for air convection.

3. The high-voltage cable grounding loop current limiting device based on a novel structure according to claim 1 is characterized in that: The current limiting system includes a support plate, a base, an A-phase resistor module, an A-phase metal slide rail, a B-phase resistor module, a B-phase metal slide rail, a C-phase resistor module and a C-phase metal slide rail, wherein the base is installed at an internal central position, the support plate is installed above the base, the A-phase resistor module, the B-phase resistor module and the C-phase resistor module are fixed to the support plate through support insulators, the A-phase metal slide rail is installed below the A-phase resistor module and fixed to the support plate through support insulators, the B-phase metal slide rail is installed below the B-phase resistor module and fixed to the support plate through support insulators, and the C-phase metal slide rail is installed below the C-phase resistor module and fixed to the support plate through support insulators.

4. The high-voltage cable grounding loop current limiting device based on a novel structure according to claim 3 is characterized in that: The A-phase resistance module, the B-phase resistance module and the C-phase resistance module have the same structure, and the A-phase metal slide rail, the B-phase metal slide rail and the C-phase metal slide rail have the same structure.

5. The high-voltage cable grounding loop current limiting device based on a novel structure according to claim 4 is characterized in that: The A-phase resistance module includes an internal circuit and six extending terminals, and the six terminals are terminal 0, terminal 1, terminal 2, terminal 3, terminal 4 and terminal 5.

6. The high-voltage cable grounding loop current limiting device based on a novel structure according to claim 5 is characterized in that: The internal circuit includes a No. 1 chip resistor unit, a No. 2 chip resistor unit, a No. 3 chip resistor unit, a No. 4 chip resistor unit and a No. 5 chip resistor unit. The No. 5 chip resistor unit, the No. 4 chip resistor unit, the No. 3 chip resistor unit, the No. 2 chip resistor unit and the No. 1 chip resistor unit are connected in sequence through wires. The No. 1, 2, 3, 4 and 5 chip resistor units are respectively provided with No. 1, 2, 3, 4 and 5 terminals. The other end of the No. 1 chip resistor unit is provided with a No. 0 terminal, and the No. 0 terminal is grounded.

7. The high-voltage cable grounding loop current limiting device based on a novel structure according to claim 6 is characterized in that: The sheet resistor unit No. 1, sheet resistor unit No. 2, sheet resistor unit No. 3, sheet resistor unit No. 4 and sheet resistor unit No. 5 have the same structure, sheet resistor units No. 1, 2, 3, 4 and 5 are fixed by four insulating connecting rods, and sheet resistor units No. 1, 2, 3, 4 and 5 are isolated by insulating gaskets.

8. The high-voltage cable grounding loop current limiting device based on a novel structure according to claim 4 is characterized in that: The A-phase metal slide rail includes a slide rail shell and a slider arranged inside the slide rail shell. Three slide rail grooves are opened on the surface of the slide rail shell. The slider has terminals extended upward: one wiring terminal and two fixed terminals. The one wiring terminal and the two fixed terminals are in a mountain shape and are respectively inserted into the three slide rail grooves opened on the surface of the slide rail shell. The fixed terminals are provided with threads and are fixed by tightening screws, so that the relative positions of the slider and the slide rail shell are fixed, and the wiring terminals of the slider are in contact with the wiring terminals of the resistor module.

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