Gas-insulated ring main unit and grounding switch

Abstract

The present invention belongs to the technical field of high-voltage switch devices, and relates to a gas-insulated ring main unit and a grounding switch. In the prior art, when cables in a ring main unit need to be overhauled, it is necessary to dismount the cables from a wall bushing, a voltage-withstand or through-flow test is then performed, and the cables are reset after the test is completed, resulting in a laborious overhauling process. The grounding switch in the present invention comprises grounding contacts corresponding to outgoing cables of all phases on a one-to-one basis, wherein grounding sides of the grounding contacts are all connected to the outer side of a gas enclosure by means of connecting conductors and are all then connected to a grounding busbar, and the grounding busbar is connected to the ground. When cables in a power supply loop of a gas-insulated ring main unit need to be tested or overhauled, it is only necessary to dismount the busbar, such that the overhauling process is greatly simplified.

Description

A gas insulated ring main unit and grounding switch Technical Field

[0001] The invention relates to a gas-insulated ring network cabinet and a grounding switch, belonging to the technical field of high-voltage switchgear. Background Art

[0002] Gas-insulated ring main unit (GIN) is widely used in the field of high-voltage switches, but sometimes it is necessary to test or repair the cables on its power supply circuit. Traditional GINs generally include a sealed gas chamber, which is equipped with an arc extinguishing chamber and a three-position switch with soft connections in series. The three-position switch includes an isolating static contact, an isolating moving contact, and a grounding static contact. A grounding bus is provided on the side of the grounding static contact, all of which are sealed in a metal gas box. The grounding input and output lines connected to the grounding bus are grounded using cables through wall bushings on the wall of the sealed gas chamber.

[0003] For example, the Chinese patent application document with application publication number CN116666147A discloses a linkage switch and ring network cabinet, in which the linkage switch includes an arc extinguishing chamber and a three-position switch. The isolating static contact of the three-position switch in the gas box is electrically connected to the bus bushing through the bus side branch bar, the grounding static contact is arranged on the grounding bus in the gas box, the outgoing line branch bar is connected to the outgoing line bushing, and the outgoing line branch bar is introduced to the outside of the gas box; the Chinese patent document with authorization announcement number CN219677926U discloses a load switch ring network cabinet, in which the composite switch includes a grounding switch beam for grounding, which serves as a grounding bus for each phase and is arranged on the inside of the gas box.

[0004] In the above scheme, when the outgoing cable needs to be inspected, the outgoing cable needs to be removed from the wall bushing on the gas box, and then a pressure or current test is performed to locate the fault in the circuit. After the test is completed, the outgoing cable is put back in place. The entire maintenance process requires the removal of the main cable in the cable room, which is more troublesome and also affects the safety of the operator to a certain extent when the cable is removed.

[0005] Summary of the Invention

[0006] The purpose of the present invention is to provide a gas insulated ring main unit and a grounding switch to solve the problem that the operation process of testing and repairing the outgoing side cable is relatively troublesome.

[0007] To achieve the above object, the solution of the present invention includes:

[0008] A grounding switch includes grounding contacts corresponding to the outgoing cables of each phase. The grounding sides of the grounding contacts are connected to the outside of the gas box through connecting conductors and then connected to the grounding busbar, which is connected to the ground.

[0009] The present invention arranges a busbar for grounding outside the gas box, and connects the grounding contacts that can be connected to the cables of each phase through the grounding knife switch to the outside of the gas box through connecting conductors, and then connects to the busbar. The connecting conductors of each phase connected to the busbar can be connected to the cables of each phase through the grounding knife switch, and the busbar has the function of testing the current flow of each phase cable when it is removed. Without affecting the grounding of the grounding switch, when it is necessary to inspect or test the outgoing cables connected when the grounding contacts are closed, only the busbar needs to be removed. This process does not require removing the main cable from the cable room, which is simple to operate and greatly improves the safety of the operator.

[0010] Furthermore, a bushing corresponding to each phase is provided on the side wall of the gas box, the grounding side of the connecting conductor is connected to the end of the bushing located inside the gas box, and the end of the bushing located outside the gas box is connected to the grounding bus.

[0011] By setting up an electrical connector such as a wall bushing, the connecting conductor of the grounding contact in the gas box is connected to the bus outside the gas box. The structure is simple. After removing the bus, the pressure or current test can be carried out using the corresponding interface of the bushing on the outside of the gas box, which is easy to operate.

[0012] Furthermore, the grounding contact includes a grounding static contact and a grounding movable contact. The grounding movable contact is connected to each phase outgoing cable respectively, and the grounding static contact serves as a grounding side for connecting to the ground.

[0013] The grounding static contact is connected to the ground as the grounding side. Since the grounding static contact has a simple structure, it is more convenient to make changes at the static contact, and the design structure is simple.

[0014] Furthermore, the connecting conductor is arranged on an insulating fixing piece for fixing the grounding static contact, and the connecting conductor includes a fixing side, which is connected to the grounding static contact fixed on the insulating fixing piece.

[0015] By fixing the connecting conductor on the insulating fixing piece to which the static contact is fixed, the structure is made more stable.

[0016] Furthermore, the connecting conductor and the grounding static contact are arranged on the same side of the insulating fixing piece.

[0017] By arranging the connecting conductor and the grounding static contact on the same side of the insulating fixing piece, the connection is more convenient and the conductive effect is better.

[0018] Furthermore, the fixed side of the connecting conductor and the fixed portion of the grounding static contact are fixed to the insulating fixing member by means of bolts.

[0019] The connecting conductor and the grounding static contact are fixed by bolts, and the fixing method is simple and stable.

[0020] Furthermore, the connecting conductor is a connecting copper rod.

[0021] By setting the connecting conductor as a connecting copper rod, the connecting copper rod has better conductivity than other conductors and is cost-effective.

[0022] A gas-insulated ring main unit includes a grounding switch, which includes grounding contacts corresponding one to each phase outgoing cable. The grounding sides of the grounding contacts are connected to the outside of the gas box through connecting conductors and then connected to a grounding busbar, which is connected to the ground.

[0023] The present invention places a busbar for grounding outside the gas box. Grounding contacts, which can be connected to each phase cable via a grounding switch, are connected to the outside of the gas box via connecting conductors. The grounding contacts are then connected to the busbar. The connecting conductors for each phase connected to the busbar can each be connected to each phase cable via the grounding switch. When the busbar is removed, it is possible to perform a current flow test on each phase cable. When the outgoing cables connected when the grounding contacts are closed need to be inspected or tested without affecting the grounding of the grounding switch, only the busbar needs to be removed. This process does not require the removal of the main cable from the cable compartment, making the operation simple and greatly improving operator safety.

[0024] Furthermore, a bushing corresponding to each phase is provided on the side wall of the gas box, the grounding side of the connecting conductor is connected to the end of the bushing located inside the gas box, and the end of the bushing located outside the gas box is connected to the grounding bus.

[0025] By setting up an electrical connector such as a wall bushing, the connecting conductor of the grounding contact in the gas box is connected to the bus outside the gas box. The structure is simple. After removing the bus, the pressure or current test can be carried out using the corresponding interface of the bushing on the outside of the gas box, which is easy to operate.

[0026] Furthermore, the grounding contact includes a grounding static contact and a grounding movable contact. The grounding movable contact is connected to each phase outgoing cable respectively, and the grounding static contact serves as a grounding side for connecting to the ground.

[0027] The grounding static contact is connected to the ground as the grounding side. Since the grounding static contact has a simple structure, it is more convenient to make changes at the static contact, and the design structure is simple.

[0028] Furthermore, the connecting conductor is arranged on an insulating fixing piece for fixing the grounding static contact, and the connecting conductor includes a fixing side, which is connected to the grounding static contact fixed on the insulating fixing piece.

[0029] By fixing the connecting conductor on the insulating fixing piece to which the static contact is fixed, the structure is made more stable.

[0030] Furthermore, the connecting conductor and the grounding static contact are arranged on the same side of the insulating fixing piece.

[0031] By arranging the connecting conductor and the grounding static contact on the same side of the insulating fixing piece, the connection is more convenient and the conductive effect is better.

[0032] Furthermore, the fixed side of the connecting conductor and the fixed portion of the grounding static contact are fixed to the insulating fixing member by means of bolts.

[0033] The connecting conductor and the grounding static contact are fixed by bolts, and the fixing method is simple and stable.

[0034] Furthermore, the connecting conductor is a connecting copper rod.

[0035] By setting the connecting conductor as a connecting copper rod, the connecting copper rod has better conductivity than other conductors and is cost-effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] FIG1 is a schematic structural diagram of a grounding switch for a gas insulated ring main unit in an open state;

[0037] FIG2 is a schematic structural diagram of the ground loop assembly in FIG1 ;

[0038] 3 is a schematic structural diagram of a grounding switch for a gas insulated ring main unit according to the present invention in a closed state after the busbar is removed;

[0039] In the figure: 1. Static contact seat; 2. Grounding moving contact; 3. Grounding static contact; 4. Insulation fixing piece; 5. Connecting conductor; 6. Bushing; 7. Busbar; 8. Gas box wall. DETAILED DESCRIPTION

[0040] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0041] The idea of ​​the present invention is to set the busbar for grounding outside the gas box, connect the grounding busbar to the ground, and connect the grounding contacts corresponding to each phase line outgoing cable in the gas box to the grounding busbar set outside the gas box through various connecting conductors. Without affecting the grounding of the original grounding switch, the present invention can also test the insulation and current performance of the power supply loop cable of the ring network cabinet and locate faults in the circuit. When maintenance is required, the grounding busbar is removed and the grounding contact is closed. This process does not require the main cable to be removed from the cable room, which greatly improves the safety of the operator.

[0042] Grounding switch embodiment 1:

[0043] An embodiment of a grounding switch of the present invention is shown in FIG1 : comprising a static contact seat 1 , a grounding movable contact 2 , a grounding static contact 3 , an insulating fixing 4 , a connecting conductor 5 , a bushing 6 , a busbar 7 , and a gas box wall 8 .

[0044] The grounding static contact 3 and the connecting conductor 5 are both fixed on the same side surface of the insulating fixing member 4. The grounding movable contact 2 corresponding to the grounding static contact is fixed on the static contact seat 1. The other end of the static contact seat 1 is connected to the outgoing cables of each phase. In this embodiment, the insulating fixing member 4 uses an insulating fixing plate to fix the grounding static contact 3 and the connecting conductor 4. In this embodiment, the connecting conductor 4 is connected to the grounding static contact 3 using a connecting copper rod.

[0045] As a further explanation of the fixing method of the connecting copper rod 5 and the grounding static contact on the insulating fixing plate 4, as shown in Figure 2, the insulating fixing plate 4 is provided with two fixing holes, and the fixing part of the grounding static contact 3 on the side of the insulating fixing plate 4 is simultaneously pressed and connected with the fixed side of the connecting copper rod 5 by a bolt passing through each fixing hole, so that the fixation of the grounding static contact 3 and the connecting copper rod 5 is more firmly. In other embodiments, the grounding static contact 3 can also be welded to the insulating fixing plate 4, and the connecting copper rod 5 is fixed to the side of the grounding static contact 3 through the fixing hole and connected to the grounding static contact 3.

[0046] The gas box wall is provided with holes for three bushings 6 corresponding to the three phase lines to pass through. The three bushings are installed on the gas box wall 8 by welding nuts and bolts on the gas box wall 8. One end of the bushing inside the gas box is respectively connected to the end of each connecting copper rod 5 away from the grounding static contact 3, and one end of the bushing outside the gas box is connected to the bus 7.

[0047] As shown in Figure 3, when the grounding switch is closed, that is, the grounding movable contact 2 rotates to the grounding static contact 3 and contacts the grounding static contact 3, the outgoing cable connected to the static contact seat 1 at the end of the bushing 6 outside the gas box is connected. When the grounding switch is opened, as shown in Figure 1, the outgoing cable connected to the static contact seat 1 at the end of the bushing 6 outside the gas box is disconnected. When the cable needs to be tested or repaired, the grounding switch is placed in the closed position, the busbar 7 is removed, and the outgoing cable connected to the static contact seat 1 is subjected to insulation or current flow test through the three-phase bushing 6. This process does not require the removal of other components of the box. Testing or maintenance can be carried out by removing only the busbar 7 outside the box, which is simple to operate.

[0048] Grounding switch embodiment 2:

[0049] An embodiment of a grounding switch of the present invention differs from embodiment 1 in that the grounding movable contact in the grounding contact is connected to the ground as the grounding side, the grounding side is connected to the bus outside the gas box through a connecting conductor, and the grounding static contact in the grounding contact is connected to the outgoing cables of each phase line.

[0050] Ring main unit example:

[0051] An embodiment of a gas-insulated ring main unit of the present invention includes a grounding switch. The grounding switch has been described in detail in the above-mentioned grounding switch embodiments 1 and 2 and will not be described in detail here.

Claims

1. A grounding switch, comprising grounding contacts corresponding to each phase outgoing cable, characterized in that: The grounding sides of the grounding contacts are connected to the outside of the air box through connecting conductors and then connected to a grounding bus bar, and the grounding bus bar is connected to the ground.

2. The grounding switch according to claim 1, characterized in that: The side wall of the gas box is provided with bushings corresponding to each phase one by one, the grounding side of the connecting conductor is connected to one end of the bushing located inside the gas box, and one end of the bushing located outside the gas box is connected to the grounding bus.

3. The grounding switch according to claim 1, characterized in that: The grounding contact comprises a grounding static contact and a grounding movable contact. The grounding movable contact is respectively connected to the outgoing cables of each phase, and the grounding static contact serves as the grounding side and is used to be connected to the ground.

4. The grounding switch according to claim 1, characterized in that: The connecting conductor is arranged on an insulating fixing piece for fixing a grounding static contact, and the connecting conductor comprises a fixing side, and the fixing side is connected to the grounding static contact fixed on the insulating fixing piece.

5. The grounding switch according to claim 4, characterized in that: The connecting conductor and the grounding static contact are arranged on the same side of the insulating fixing member.

6. The grounding switch according to claim 5, characterized in that: The fixed side of the connecting conductor and the fixed part of the grounding contact are fixed on the insulating fixing member by means of bolts.

7. The grounding switch according to claim 1, characterized in that: The connecting conductor is a connecting copper rod.

8. A gas insulated ring main unit, characterized in that: It comprises a grounding switch as claimed in any one of claims 1 to 7.

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