CN105552770A - Connection body between high-voltage sleeve pipe of transformer and gas insulated switchgear (GIS) device - Google Patents

Abstract

A connecting body between a transformer high-voltage bushing and GIS equipment, which belongs to the technical field of high-voltage power transmission and transformation, and is characterized in that: on the main transformer side, an inflatable terminal and an inflatable insulating sleeve are installed outside the main transformer high sleeve, and the high sleeve The electrical outlet and the internal conductive rod of the inflatable terminal are plugged and fixed through electrical connectors; on the GIS side, a set of GIS terminals is added on the GIS bushing side to change the SF6 gas insulation method to the air insulation method. Beneficial effects are: 1) The new main transformer high-voltage bushing and GIS bushing are connected in a simple way, the structure design is reasonable, and the operation performance is reliable; 2) This structure is easy to disassemble and assemble during maintenance and has obvious disconnection points, and safety measures Reliable; 3) The wiring is convenient during the maintenance test of the main transformer. The maintenance test is carried out without opening the maintenance hand hole and exhausting. 4) After the modification, it is only necessary to disconnect the lead during the test, and there is no need to disassemble the GIS casing, which reduces the workload and equipment failure rate.

Description

Connecting body between high-voltage bushing of transformer and GIS equipment

technical field

The invention belongs to the technical field of high-voltage power transmission and transformation.

Background technique

At present, GIS complete sets of power distribution equipment are widely used in 66kV~500kV power distribution systems at home and abroad to replace open switch stations. Most of the high-voltage side of the main transformer and the GIS outgoing line are directly connected (the high-voltage casing is sealed in the GIS casing). Considering the complex charging and exhausting process of the GIS equipment, the long construction period and the possible instability caused by the high-voltage equipment, When conducting transformer tests in each power plant, the test period is extended, or the GIS grounding switch is connected, and a section of GIS equipment is used to roughly test the main transformer and compare the numerical trend to roughly judge the state of the main transformer. The distance to the GIS power distribution equipment is long, and considering that the contact resistance at the grounding knife switch has a great influence on the DC resistance value of the transformer, the measured value can only be used as a reference, and it cannot be accurately tested according to the requirements of the preventive test regulations.

The high voltage side of the main transformer and the GIS outgoing line adopt the direct connection method (the high sleeve is sealed in the GIS sleeve). The disadvantages: 1. During the annual transformer test, the SF6 gas in the GIS must be recovered, the GIS hand hole must be opened, and the lead shall be disconnected and connected. , Vacuuming and SF6 gas filling work, each test generally takes 3 days. 2. When the factory power system adopts the mode of main transformer reversing with factory power, the main transformer undertakes the job of reversing the factory power at the same time, and the maintenance time cannot be effectively guaranteed; 3. Frequent preventive tests of the routine main transformer The charging and discharging of SF6 gas will easily cause the GIS equipment to be poorly sealed, leak, get damp, enter dust, and cause environmental pollution due to SF6 gas leakage; 4. If this type of structure is used for the main transformer pressure test, a section of GIS casing needs to be removed This increases the amount of work and is not conducive to the safe and stable operation of the equipment. 5. The contact resistance at the grounding switch has a great influence on the DC resistance value of the transformer, and the measured value can only be used as a reference.

Contents of the invention

The purpose of the present invention is to provide a connecting body between the transformer high-voltage bushing and GIS equipment, which does not need to disassemble the GIS bushing, and reduces the maintenance workload and equipment failure rate.

Technical scheme of the present invention is as follows:

On the side of the main transformer: add an inflatable terminal and an inflatable insulating sleeve outside the high casing of the main transformer, and the electrical outlet of the high casing and the internal conductive rod of the inflatable terminal are plugged and fixed through electrical connectors;

On the GIS side: add a set of GIS terminals on the GIS bushing side to change the SF6 gas insulation method to air insulation method. Composite insulating skirts on the outside of the terminals increase the electrical creepage distance.

Use soft wires and equipment clamps to connect with the main transformer high sleeve terminal and the GIS terminal terminal respectively, and use bolts to fix them.

The beneficial effects of the present invention are: 1) The new main transformer high-voltage bushing and GIS bushing are connected in a simple way, the structure design is reasonable, and the operation performance is reliable; 2) This structure is easy to disassemble and assemble during maintenance and has obvious disconnection points , The safety measures are reliable; 3) The wiring is convenient during the maintenance test of the main transformer, and the maintenance test is carried out without opening the maintenance hand hole and exhausting. 4) When carrying out large-scale tests such as main transformer pressure resistance, the original connection method must remove the GIS bushing before proceeding. After the modification, only the lead needs to be disconnected during the test, and the GIS bushing does not need to be disassembled, which reduces the workload and equipment failure rate .

Description of drawings

Fig. 1 is a schematic diagram of the structure of the present invention.

detailed description

The present invention will be further described below in conjunction with accompanying drawing:

As shown in the figure, 1 is the GIS terminal, 2 is the equipment clamp, 3 is the flexible wire, 4 is the inflatable terminal of the main variable height sleeve, 5 is the electrical connector, 6 is the inflatable insulating sleeve, and 7 is the main variable height sleeve , 8 are the main transformer body.

On the main transformer side: Install an inflatable (SF6) type terminal 4 and an inflatable (SF6) insulating sleeve 6 on the outside of the main transformer high sleeve, and the electrical outlet of the high sleeve and the internal conductive rod of the inflatable (SF6) type terminal are inserted through the electrical connector 5 catch;

GIS side: Add a set of GIS terminals on the GIS bushing side to change the SF6 gas insulation method to air insulation method. Composite insulating skirts on the outside of the terminals increase the electrical creepage distance.

Use soft wires and equipment clamps to connect with the main transformer high sleeve terminal and the GIS terminal terminal respectively, and use bolts to fix them.

By adopting this new connection structure, the electrical connection sealed inside the GIS bushing is converted into a connection and fixed part exposed to the outside of the air, and the flexible connection wire can be removed directly for maintenance, test disconnection, and test, which greatly facilitates maintenance. , Disconnection, testing, wiring and other work during the test.

Claims (2)

1. A connecting body between a transformer high voltage bushing and GIS equipment, characterized in that: On the main transformer side, an inflatable terminal and an inflatable insulating sleeve are installed outside the main transformer high sleeve, and the electrical outlet of the high sleeve and the internal conductive rod of the inflatable terminal are plugged and fixed through electrical connectors; On the GIS side, a set of GIS terminals is added on the GIS bushing side to change the SF6 gas insulation method to air insulation method. 2. The connecting body between a kind of transformer high-voltage bushing and GIS equipment as claimed in claim 1, it is characterized in that: use soft lead wire, equipment clamp to be connected with main transformer high sleeve terminal and GIS terminal terminal respectively, adopt Bolt fixing method.