Small-current grounding line selection device

Abstract

The utility model relates to the technical field of grounding line selection devices, in particular to a small-current grounding line selection device, which is characterized in that a rubber ring and an inner box brim of an inner box door prevent rainwater from flowing into an inner cavity of the inner box from a gap between the inner box door and a groove, and protect a grounding line selection box in the inner cavity of the inner box from being invaded by the rainwater; the rubber strip at the bottom of the inner box increases the friction force between the grounding line selection box and the inner box, and avoids the failure of the grounding line selection box caused by the collision between the grounding line selection box and the inner box. The inner box is lifted by the supporting legs, so that the grounding line selection box in the inner box is protected from being eroded by dirt such as accumulated water, and the service life of the grounding line selection box is prolonged; the outer box door and the outer box are locked together through the circular ring, so that the outer box becomes a complete shell, if the outer box is subjected to lightning or broken high-voltage electric shock, all charges are distributed on the outer surface of the outer box, the grounding line selection box is completely isolated from the charges, damage and interference of high-voltage discharge to the grounding line selection box are avoided, and the line selection accuracy of the grounding line selection box is guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to ground connection line selection device technical field especially is a small current ground connection line selection device. BACKGROUND

[0002] Single-phase grounding is a common fault of power system, which means that one phase of three-phase system and ground have short circuit.

[0003] The main reasons for single-phase grounding fault are as follows:

[0004] 1) The wire falls to the ground or is on the cross arm.

[0005] 2) The wire is tied or fixed in the insulator, and falls to the cross arm or the ground.

[0006] 3) The wire wind deviation is too large, and the distance from the building is too close.

[0007] 4) The high-voltage lead of the transformer is broken.

[0008] 5) The single-phase insulation of the high-voltage winding of the distribution transformer is broken or grounded.

[0009] 6) The insulator is broken.

[0010] 7) The branch fuse on the line is broken.

[0011] 8) The pull belt of the upper cross arm of the conductor on the same pole is detached and placed on the lower conductor.

[0012] 9) The line is struck by lightning.

[0013] 10) The tree channel is not smooth, which causes the tree to contact the conductor.

[0014] 11) Bird damage.

[0015] 12) Floating objects (such as plastic cloth, kites, etc.)

[0016] 13) Other accidental or unknown reasons

[0017] Among the above reasons, the wire breakage, insulator breakdown and tree short circuit are the main reasons for the single-phase grounding fault of the distribution line. According to the statistics of single-phase grounding fault reasons in recent years, the above three reasons account for more than 85% of the total fault reasons.

[0018] In today's power station, small current grounding device is widely used in various large and small power stations, and each power station has at least one small current grounding device. It is widely used in power plants, substations, photovoltaic power stations, hydropower stations, chemical industry, metallurgy and other large owners in the power system. It can be seen that the use range of small current grounding line selection is wide. Small current grounding line selection device can accurately judge the switch cabinet where the fault current is located, so that the operation and maintenance personnel can find and handle it in time, solve the fault problem in time and ensure the safe and stable operation of the power station. The function of small current line selection device is to determine the fault line, and the principle of line selection is that the three-phase voltage of the system is symmetrical and balanced under normal circumstances in the small current system, the phase angle is also 120 degrees apart, and the capacitance to ground of the three phases is also the same. The zero sequence current flowing into the zero sequence mutual inductor is close to 0. When single-phase grounding fault occurs at a certain place of the line. The open delta voltage will be generated, and the zero sequence voltage will be generated. At this time, each zero sequence mutual inductor of the system will have zero sequence current passing through. However, the zero sequence currents flowing through the fault and non-fault are different in size and direction, so the fault point can be judged by judging the size and direction of the zero sequence current.

[0019] The small current grounding device used at present is seriously affected by the external power environment. If it is struck by lightning or high-voltage in rainy weather, the small current grounding device will be disturbed or damaged, which seriously affects the accuracy of line selection. Practical new type content

[0020] The main purpose of the utility model is to provide a small current grounding line selection device to solve the problem of serious influence of external power environment in the related art.

[0021] In order to achieve the above purpose, according to one aspect of the utility model, a small current grounding line selection device is provided, which comprises an outer box, the outer box is made of copper, the outer box is provided with an outer box inner cavity, each surface of the outer box is provided with a plurality of rectangular holes, the rectangular holes penetrate the outer box and communicate with the outer box inner cavity, the front surface of the outer box is provided with an outer box door, the outer box door is hinged to the outer box, the left side of the outer box door is provided with a rectangular hole, the rectangular hole penetrates the outer box door, the front side of the outer box is provided with a ring buckle at the position corresponding to the rectangular hole, and the ring buckle is fixedly connected with the outer box.

[0022] Further, the ring buckle comprises a column body, one end of the column body is fixedly connected with the outer box, the other end of the column body is provided with a connecting block, the connecting block is rotatably connected with the column body, the top end of the connecting block is provided with a circular ring, and the circular ring is fixedly connected with the connecting block.

[0023] Further, the inner box is arranged in the outer box, the inner box comprises an inner box inner cavity, the inner box is provided with an inner box door, and the inner box door is hinged to the inner box.

[0024] Further, the inner box door is internally surrounded by a rubber ring, which is fixedly connected to the inner box door, and a handle is externally arranged on the inner box door and fixedly connected to the inner box door.

[0025] Further, the inner box is provided with a groove at a corresponding position of the rubber ring, the cross section of the groove is smaller than that of the rubber ring, and the inner box is provided with an inner box eave, which is fixedly connected to the inner box.

[0026] Further, the inner side of the bottom of the inner box is provided with a plurality of rubber strips, which are fixedly connected to the inner box, and the middle of the bottom of the inner box is provided with a circular hole, which penetrates through the inner box and is in communication with the inner cavity of the outer box.

[0027] Further, the outer side of the bottom of the inner box is provided with a supporting leg at each corner, the supporting leg comprises a supporting leg column, a buffer pad and an arc-shaped strip, one end of the supporting leg is fixedly connected to the inner box, the other end is fixedly connected to the buffer pad, the surface of the buffer pad is fixedly provided with the arc-shaped strip, and the arc-shaped strip is evenly distributed on the bottom of the buffer pad in a diverging manner.

[0028] Further, the inner cavity of the outer box is internally provided with a grounding line selector box, which is placed on the rubber strips at the bottom of the inner box.

[0029] Compared with the prior art, the rubber ring of the inner box door is completely embedded in the groove and is pressed tightly, rainwater is blocked by the rubber ring and cannot flow into the inner cavity of the inner box from the gap between the inner box door and the groove in rainy weather, the outer convex inner box eave covers the inner box door thereunder and blocks rainwater from flowing into the inner cavity of the inner box from the gap between the top of the inner box door and the groove, the ability of the outer box to isolate rainwater is strengthened, and the grounding line selector box in the inner cavity of the inner box is protected from rainwater invasion; the rubber strips at the bottom of the inner box increase the friction between the grounding line selector box and the inner box, so that the grounding line selector box cannot move back and forth in the inner box when external force or vibration is encountered, and collision between the grounding line selector box and the inner box is avoided to prevent the grounding line selector box from malfunctioning; the supporting leg lifts up the inner box, protects the grounding line selector box in the inner box from being eroded by accumulated water and the like, and prolongs the service life of the grounding line selector box; the cross section of the buffer pad is larger than that of the supporting leg column, the contact area between the inner box and the outer box is increased, and the inner box can be placed more stably in the outer box; the arc-shaped strip is distributed on the bottom of the buffer pad in a diverging manner, the friction between the buffer pad and the outer box is increased, relative movement between the inner box and the outer box is prevented, and collision between the grounding line selector box and the inner box is avoided; the circular ring locks the outer box door and the outer box together, so that the outer box becomes a complete shell, if the outer box is struck by lightning or high-voltage electricity, the electric charge is distributed on the outer surface of the outer box, the grounding line selector box is completely isolated from the electric charge, the damage and interference of high-voltage discharge on the grounding line selector box are avoided, and the accuracy of line selection of the grounding line selector box is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is a whole schematic view of the utility model;

[0031] Figure 2 It is the outer box structure schematic view of the utility model;

[0032] Figure 3 It is the inner box structure schematic view of the utility model;

[0033] Figure 4 It is the ring buckle structure schematic view of the utility model;

[0034] Figure 5 It is the supporting leg structure schematic view of the utility model.

[0035] Illustration:

[0036] 1, outer box;101, outer box inner cavity;102, outer box door;103, rectangular hole;104, ring buckle;105, outer box hole;1041, cylinder;1042, connecting block;1043, circular ring;

[0037] 2, inner box;201, inner box inner cavity;202, inner box door;203, rubber ring;204, round hole;205, rubber strip;206, recess;207, supporting leg;208, handle;209, inner box eave;

[0038] 2071, buffer pad;2072, arc-shaped strip;2073, supporting leg column;

[0039] 3, grounding line selection box. DETAILED DESCRIPTION

[0040] In order to further illustrate the technical means and effects adopted by the utility model for realizing the predetermined utility model purposes, the specific implementation, structure, features and effects according to the utility model are described in detail as follows by combining with the drawings and preferred embodiments.

[0041] Please refer to Figures 1 to 5The embodiment provides a small-current grounding line selection device, which comprises an outer box 1 made of copper, wherein the outer box 1 is provided with an outer box cavity 101, each surface of the outer box 1 is provided with a plurality of rectangular holes 103, the rectangular holes 103 reduce the self weight of the outer box 1 and facilitate carrying, in case of bad weather, strong wind passes through the rectangular holes 103 and the wind force acting on the outer box 1 is reduced, so that the outer box 1 is not easily blown down, the rectangular holes 103 penetrate the outer box 1 and are communicated with the outer box cavity 101, a line to be detected passes into the outer box 1 from an outer box hole 105 at the bottom of the outer box 1, the outer box 1 is provided with an outer box door 102, the outer box door 102 is hinged to the outer box 1, the left side of the outer box door 102 is provided with a rectangular hole 103 penetrating the outer box door 102, the front side of the outer box 1 is provided with a ring buckle 104 corresponding to the rectangular hole 103, the ring buckle 104 is fixedly connected with the outer box 1, the ring buckle 104 fixes the outer box door 102 on the outer box 1, so that the outer box 1 becomes a complete shell, if the outer box 1 is struck by lightning or high-voltage electricity, the electric charge is completely distributed on the outer surface of the outer box 1, the grounding line selection box 3 is completely isolated from the electric charge, the damage and interference of high-voltage discharge on the grounding line selection box 3 are avoided, and the accuracy of line selection of the grounding line selection box 3 is ensured.

[0042] The ring buckle 104 comprises a column body 1041, one end of the column body 1041 is fixedly connected with the outer box 1, the other end of the column body 1041 is provided with a connecting block 1042, the connecting block 1042 is rotationally connected with the column body 1041, the top end of the connecting block 1042 is provided with a circular ring 1043, the circular ring 1043 is fixedly connected with the connecting block 1042, the circular ring 1043 is parallel to the rectangular hole 103 in rotation, the outer box door 102 can be opened, the circular ring 1043 is perpendicular to the rectangular hole 103 in rotation, and the ring buckle 104 fixes the outer box door 102 on the outer box 1.

[0043] The inner box 2 is arranged in the outer box 1, the inner box 2 comprises an inner box cavity 201 for containing the grounding line selection box 3, the inner box 2 is provided with an inner box door 202 hinged to the inner box 2, and the opening of the inner box door 202 is facilitated.

[0044] The inner box door 202 is provided with a rubber ring 203 around the inner box door 202, the rubber ring 203 is fixedly connected with the inner box door 202, the rubber ring 203 blocks the gap between the inner box door 202 and the inner box 2 when the inner box door 202 is closed, and rainwater is prevented from entering the inner box cavity 201, and the inner box door 202 is provided with a handle 208 fixedly connected with the inner box door 202.

[0045] The inner box 2 is provided with a groove 206 corresponding to the rubber ring 203, the cross section of the groove 206 is smaller than the cross section of the rubber ring 203, the rubber ring 203 is pressed into the groove 206 and can completely block the groove 206, the inner box 2 is provided with an inner box eave 209, the inner box eave 209 is fixedly connected with the inner box 2, the inner box eave 209 is convex outward, covers the inner box door 202 thereunder, blocks rainwater from flowing into the inner cavity 201 of the inner box from the gap between the top of the inner box door 202 and the groove 206, strengthens the ability of the outer box 1 to isolate rainwater, and protects the grounding line selection box 3 in the inner cavity 201 of the inner box from being invaded by rainwater.

[0046] The inner box 2 is provided with a groove 206 corresponding to the rubber ring 203, the cross section of the groove 206 is smaller than the cross section of the rubber ring 203, the rubber ring 203 is pressed into the groove 206 and can completely block the groove 206, the inner box 2 is provided with an inner box eave 209, the inner box eave 209 is fixedly connected with the inner box 2, the inner box eave 209 is convex outward, covers the inner box door 202 thereunder, blocks rainwater from flowing into the inner cavity 201 of the inner box from the gap between the top of the inner box door 202 and the groove 206, strengthens the ability of the outer box 1 to isolate rainwater, and protects the grounding line selection box 3 in the inner cavity 201 of the inner box from being invaded by rainwater.

[0047] The inner box 2 is provided with a groove 206 corresponding to the rubber ring 203, the cross section of the groove 206 is smaller than the cross section of the rubber ring 203, the rubber ring 203 is pressed into the groove 206 and can completely block the groove 206, the inner box 2 is provided with an inner box eave 209, the inner box eave 209 is fixedly connected with the inner box 2, the inner box eave 209 is convex outward, covers the inner box door 202 thereunder, blocks rainwater from flowing into the inner cavity 201 of the inner box from the gap between the top of the inner box door 202 and the groove 206, strengthens the ability of the outer box 1 to isolate rainwater, and protects the grounding line selection box 3 in the inner cavity 201 of the inner box from being invaded by rainwater.

[0048] The inner box 2 is provided with a groove 206 corresponding to the rubber ring 203, the cross section of the groove 206 is smaller than the cross section of the rubber ring 203, the rubber ring 203 is pressed into the groove 206 and can completely block the groove 206, the inner box 2 is provided with an inner box eave 209, the inner box eave 209 is fixedly connected with the inner box 2, the inner box eave 209 is convex outward, covers the inner box door 202 thereunder, blocks rainwater from flowing into the inner cavity 201 of the inner box from the gap between the top of the inner box door 202 and the groove 206, strengthens the ability of the outer box 1 to isolate rainwater, and protects the grounding line selection box 3 in the inner cavity 201 of the inner box from being invaded by rainwater.

[0049] The bottom of the outer box 1 below the outer box door 102 is buried in the soil and backfilled and fixed, the outer box door 102 is opened, the supporting leg 207 of the inner box 2 is placed into the inner cavity 101 of the outer box with the inner box door 202 facing outward, the inner box door 202 is pulled open by holding the handle 208, the line to be detected is inserted into the circular hole 204 at the bottom of the inner box 2 from the outer box hole 105 at the bottom of the outer box 1 and pulled out from the circular hole 204 and connected to the corresponding line position of the grounding line selection box 3, after the line is connected, the grounding line selection box 3 is placed on the rubber strip 205 in the inner cavity 201 of the inner box, the inner box door 202 is closed, the rubber ring 203 of the inner box door 202 is completely embedded in the groove 206 and pressed tightly, in rainy weather, rainwater is blocked by the rubber ring 203 and cannot flow into the inner cavity 201 of the inner box from the gap between the inner box door 202 and the groove 206, the outer protrusion of the inner box eave 209 covers the inner box door 202 thereunder to block rainwater from flowing into the inner cavity 201 of the inner box from the gap between the top of the inner box door 202 and the groove 206, thereby strengthening the ability of the outer box 1 to isolate rainwater and protecting the grounding line selection box 3 in the inner cavity 201 of the inner box from being invaded by rainwater; the rubber strip 205 at the bottom of the inner box 2 increases the friction between the grounding line selection box 3 and the inner box 2, so that the grounding line selection box 3 will not move back and forth in the inner box 2 when external force or vibration is encountered, thereby avoiding collision between the grounding line selection box 3 and the inner box 2 to cause malfunction of the grounding line selection box 3; the supporting leg 207 lifts the inner box 2 to protect the grounding line selection box 3 in the inner box 2 from being eroded by accumulated water and other pollutants and prolong the service life of the grounding line selection box 3; the cross section of the buffer pad 2071 is larger than that of the supporting leg column 2073, thereby increasing the contact area between the inner box 2 and the outer box 1 and enabling the inner box 2 to be placed more stably in the outer box 1; the arc-shaped strips 2072 are distributed in a diverging manner at the bottom of the buffer pad 2071, thereby increasing the friction between the buffer pad 2071 and the outer box 1 and preventing relative movement between the inner box 2 and the outer box 1 to cause collision between the grounding line selection box 3 and the inner box 2; the outer box door 102 is closed, the circular ring 1043 is rotated to be parallel to the rectangular hole 103 of the outer box door 102 and passes through the rectangular hole 103, the circular ring 1043 is rotated again to be perpendicular to the rectangular hole 103, the outer box door 102 is locked with the outer box 1, the outer box 1 becomes a complete shell, if the outer box 1 is struck by lightning or high-voltage electric shock, the electric charge is distributed on the outer surface of the outer box 1, the grounding line selection box 3 is completely isolated from the electric charge, the damage and interference of high-voltage discharge on the grounding line selection box 3 are avoided, and the accuracy of line selection of the grounding line selection box 3 is ensured.

[0050] The above merely describes preferred embodiments of the present application, and is not intended to limit the present application in any form. Although the present application has been disclosed with preferred embodiments, it is not intended to limit the present application. Any person skilled in the art can make minor changes or modifications to the disclosed technical content, or make equivalent embodiments with equivalent changes, without departing from the technical solution of the present application. Any modification, equivalent change or modification of the above embodiments, which does not depart from the technical solution of the present application, is still within the scope of the technical solution of the present application.

Claims

1. A small current ground line selection device comprising an outer box (1), characterized in that, The outer box (1) is made of copper, the outer box (1) is provided with an outer box cavity (101), each surface of the outer box (1) is provided with a plurality of rectangular holes (103), the rectangular holes (103) penetrate the outer box (1) and communicate with the outer box cavity (101), the front surface of the outer box (1) is provided with an outer box door (102), the outer box door (102) is hinged to the outer box (1), the left side of the outer box door (102) is provided with a rectangular hole (103), the rectangular hole (103) penetrates the outer box door (102), and the front side of the outer box (1) is provided with a ring buckle (104) corresponding to the rectangular hole (103), and the ring buckle (104) is fixedly connected with the outer box (1).

2. A small current earthed line selector device according to claim 1, characterized in that The ring buckle (104) comprises a column body (1041), one end of the column body (1041) is fixedly connected with the outer box (1), the other end of the column body (1041) is provided with a connecting block (1042), the connecting block (1042) is rotatably connected with the column body (1041), and the top end of the connecting block (1042) is provided with a circular ring (1043) fixedly connected with the connecting block (1042).

3. A small current earthed line selector device according to claim 2, characterized in that The inner box (2) is arranged in the outer box (1), the inner box (2) comprises an inner box cavity (201), and the inner box (2) is provided with an inner box door (202) hinged to the inner box (2).

4. A small current earthed line selector device according to claim 3, characterized in that The inner box door (202) is provided with a rubber ring (203) around the inner box door (202), the rubber ring (203) is fixedly connected with the inner box door (202), and the outer box door (202) is provided with a handle (208) fixedly connected with the inner box door (202).

5. A small current earthed line selector device according to claim 4, characterised in that, The inner box (2) is provided with a groove (206) corresponding to the rubber ring (203), the cross section of the groove (206) is smaller than that of the rubber ring (203), the top of the inner box (2) is provided with an inner box eave (209) fixedly connected with the inner box (2).

6. A small current earthed line selector device according to claim 5, characterized in that The inner box (2) is provided with a plurality of rubber strips (205) on the inner side of the bottom of the inner box (2), the rubber strips (205) are fixedly connected with the inner box (2), and the bottom of the inner box (2) is provided with a circular hole (204) penetrating the inner box (2) and communicating with the outer box cavity (101).

7. A small current earth selection device according to claim 6, characterised in that, The bottom outer side of the inner box (2) is provided with a support leg (207) at each corner, the support leg (207) comprises a support leg column (2073), a buffer pad (2071) and an arc-shaped strip (2072), one end of the support leg (207) is fixedly connected with the inner box (2), the other end is fixedly connected with the buffer pad (2071), the surface of the buffer pad (2071) is fixedly provided with the arc-shaped strip (2072), and the arc-shaped strips (2072) are evenly distributed on the bottom of the buffer pad (2071) in a diverging manner.

8. A small current earth selection device according to claim 7, characterised in that, The outer box cavity (101) is provided with a grounding line selection box (3), and the grounding line selection box (3) is placed on the rubber strips (205) at the bottom of the inner box (2).

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