A DC bushing based on DC GIL transmission

Abstract

The present invention provides a DC bushing based on DC GIL power transmission, which relates to the field of GIL power transmission and comprises a tube shell, wherein a conductor is arranged at the inner central axis of the tube shell, a basin insulator is arranged on the outer wall of one end of the conductor, a driving electrode is arranged on one side of the basin insulator, a three-pillar insulator is arranged on the other end of the conductor, a capacitive shielding layer is arranged between the three-pillar insulator and the driving electrode, and a gas transmission component for SF6 gas circulation is arranged on the basin insulator; the present invention gathers particles through the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer in coordination with the gas transmission component, and the particles are better gathered by cooperating with the driving electrode to drive the particles and the setting of the particle trap, thereby increasing the probability of particle capture and thus increasing the safety of the DC bushing.

Description

Technical Field

[0001] The present invention relates to the technical field of GIL power transmission, and in particular to a DC bushing based on DC GIL power transmission. Background Art

[0002] DC GILs using SF6 or SF6 / N2 mixed gas as insulating gas have the advantages of large transmission capacity, low loss, environmental friendliness and low maintenance cost. Currently, they have broad application prospects in power transmission situations with high drop, difficult land acquisition and complex cross-span.

[0003] A certain amount of metal particles will inevitably be generated during the production and manufacturing of DC GIL and the operation of the equipment. The metal particles will move in the equipment or adhere to the surface of electrodes or insulators due to the electric field force, causing breakdown of the air gap between the conductor and the casing or surface flashover of the insulator, thereby reducing the insulation performance of the equipment. Therefore, the present invention proposes a DC bushing based on DC GIL transmission to solve the problems existing in the prior art. Summary of the invention

[0004] In view of the above problems, the present invention proposes a DC bushing based on DC GIL power transmission. The DC bushing based on DC GIL power transmission cooperates with the gas transmission component through a first shielding layer, a second shielding layer, a third shielding layer, a fourth shielding layer and a fifth shielding layer to gather the particles. The driving electrode drives the particles away and the particle trap is set up, so the particles can be better gathered and the probability of particle capture is increased, thereby increasing the safety of the DC bushing.

[0005] To achieve the purpose of the present invention, the present invention is implemented through the following technical solutions: A DC bushing based on DC GIL power transmission, comprising a tube shell, a conductor is arranged at the inner central axis of the tube shell, a pot-type insulator is arranged on the outer wall of one end of the conductor, a driving electrode is arranged on one side of the pot-type insulator, a three-pillar insulator is arranged at the other end of the conductor, a capacitive shielding layer is arranged between the three-pillar insulator and the driving electrode, and a gas transmission component for SF6 gas circulation is arranged on the pot-type insulator;

[0006] The capacitor shielding layer comprises a first shielding layer, a second shielding layer, a third shielding layer, a fourth shielding layer and a fifth shielding layer, wherein a concentric circle structure is formed among the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer, the first shielding layer is connected to the inner wall of the tube shell, a particle trap is arranged on the inner wall of one end of the fifth shielding layer close to the driving electrode, both ends of the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer are concave at equal intervals in sequence, and a supporting component is arranged between the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer.

[0007] A further improvement is that the pot-type insulator comprises a mounting ring and an insulating seat, the insulating seat is in a truncated cone shape, and the insulating seat and the mounting ring are integrally formed.

[0008] A further improvement is that the gas delivery assembly includes parallel air holes and inclined air holes, the mounting ring has a plurality of groups of parallel air holes distributed in a circular array, and the side wall of the insulating seat has a plurality of groups of inclined air holes distributed in a circular array.

[0009] A further improvement is that: the extension lines of multiple groups of parallel air hole central axes are respectively located between the first shielding layer and the second shielding layer and between the second shielding layer and the third shielding layer, and the extension lines of multiple groups of inclined air hole central axes are respectively located between the first shielding layer and the second shielding layer, between the second shielding layer and the third shielding layer, between the third shielding layer and the fourth shielding layer, and between the fourth shielding layer and the fifth shielding layer.

[0010] Further improvements are: the inclination angle of the inclined air hole is 9°, the spacing between the first shielding layer and the pot-type insulator is 120 mm, and the concave spacing between the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer is 15 mm in sequence.

[0011] A further improvement is that the driving electrode is in the shape of a hollow truncated cone and the inclination angle of the driving electrode is 10°.

[0012] A further improvement is that the support assembly comprises a first support ring group and a second support ring group, and the first support ring group and the second support ring group are symmetrically arranged.

[0013] Further improvements are: the first support ring group and the second support ring group have the same structure, both include a first support ring, a second support ring, a third support ring and a fourth support ring, the first support ring, the second support ring, the third support ring and the fourth support ring are respectively located between the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer, the first support ring, the second support ring, the third support ring and the fourth support ring are each provided with a plurality of groups of particle through holes, and the particle through holes on the first support ring, the second support ring, the third support ring and the fourth support ring are staggered.

[0014] A further improvement is that the cross section of the particle through hole is trapezoidal, and the side with a larger opening of the particle through hole on the first support ring group and the second support ring group faces outward.

[0015] The beneficial effects of the present invention are as follows: the present invention realizes the pressure equalization effect inside the tube shell by setting the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer, and by staggering multiple groups of shielding layers at concentric single heights in sequence. At the same time, the setting of the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer can also increase the strength of the tube shell, further increase the pressure bearing capacity of the DC bushing, and the first shielding layer, the second shielding layer, the third shielding layer, the fourth shielding layer and the fifth shielding layer cooperate with the gas transmission component to achieve the effect of agglomerating particles. In combination with the driving electrode to drive the particles and the setting of the particle trap, the particles can be better aggregated and the probability of particle capture can be increased, thereby increasing the safety of the DC bushing and ensuring the long-term reliable operation of the DC bushing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure inside the tube shell of the present invention.

[0017] Figure 2 It is a structural schematic diagram of the basin-type insulator of the present invention.

[0018] Figure 3 It is a schematic cross-sectional view of the capacitor shielding layer of the present invention.

[0019] Figure 4 It is a cross-sectional view of the first support ring assembly of the present invention.

[0020] Figure 5 It is a schematic diagram of the gas flow direction of the gas transmission assembly of the present invention.

[0021] Among them: 1. tube shell; 2. conductor; 3. basin insulator; 4. driving electrode; 5. three-pillar insulator; 6. capacitor shielding layer; 7. first shielding layer; 8. second shielding layer; 9. third shielding layer; 10. fourth shielding layer; 11. fifth shielding layer; 12. particle trap; 13. mounting ring; 14. insulating seat; 15. parallel air holes; 16. inclined air holes; 17. first support ring group; 18. second support ring group; 19. first support ring; 20. second support ring; 21. third support ring; 22. fourth support ring; 23. particle through hole. DETAILED DESCRIPTION

[0022] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0023] according to Figure 1 , 2As shown in FIG. 3 , this embodiment proposes a DC bushing based on DC GIL power transmission, comprising a tube shell 1, a conductor 2 is provided at the inner central axis of the tube shell 1, a pot-type insulator 3 is provided on the outer wall of one end of the conductor 2, a driving electrode 4 is provided on one side of the pot-type insulator 3, a three-pillar insulator 5 is provided at the other end of the conductor 2, a capacitive shielding layer 6 is provided between the three-pillar insulator 5 and the driving electrode 4, and a gas transmission component for SF6 gas circulation is provided on the pot-type insulator 3;

[0024] The capacitor shielding layer 6 includes a first shielding layer 7, a second shielding layer 8, a third shielding layer 9, a fourth shielding layer 10 and a fifth shielding layer 11. A concentric circle structure is formed between the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11. The first shielding layer 7 is connected to the inner wall of the tube shell 1. A particle trap 12 is provided on the inner wall of the end of the fifth shielding layer 11 close to the driving electrode 4. Both ends of the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11 are concave at equal intervals in sequence. Support components are provided between the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11.

[0025] The DC bushing realizes the pressure equalization inside the tube shell 1 by setting the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11, and realizes the pressure equalization inside the tube shell 1 by staggering multiple groups of shielding layers at concentric single heights. At the same time, the setting of the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11 can also increase the strength of the tube shell 1, further increase the pressure bearing capacity of the DC bushing, and the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11 cooperate with the gas transmission component to achieve the effect of agglomerating particles. In combination with the driving electrode 4 to drive away the particles and the setting of the particle trap 12, the particles can be better aggregated and the probability of particle capture is increased, thereby increasing the safety of the DC bushing and ensuring the long-term reliable operation of the DC bushing.

[0026] The pot-type insulator 3 comprises a mounting ring 13 and an insulating seat 14 . The insulating seat 14 is in a truncated cone shape. The insulating seat 14 and the mounting ring 13 are integrally formed.

[0027] The insulating seat 14 and the mounting ring 13 are integrally formed to ensure smoothness, and the edges of the insulating seat 14 are chamfered to further increase the smoothness of the insulating seat 14 .

[0028] The gas delivery assembly includes parallel air holes 15 and inclined air holes 16 . The mounting ring 13 has a plurality of parallel air holes 15 distributed in an annular array. The side wall of the insulating seat 14 has a plurality of inclined air holes 16 distributed in an annular array.

[0029] The extension lines of the central axes of the multiple groups of parallel air holes 15 are respectively located between the first shielding layer 7 and the second shielding layer 8 and between the second shielding layer 8 and the third shielding layer 9, and the extension lines of the central axes of the multiple groups of inclined air holes 16 are respectively located between the first shielding layer 7 and the second shielding layer 8, between the second shielding layer 8 and the third shielding layer 9, between the third shielding layer 9 and the fourth shielding layer 10, and between the fourth shielding layer 10 and the fifth shielding layer 11.

[0030] Since SF6 gas is circulated inside the tube shell 1, the inclined air holes 16 are set to drive the particles to move through the flow of gas. At the same time, combined with the repulsive force of the driving electrode 4, the repelled particles can be brought into the space between the first shielding layer 7 and the second shielding layer 8, between the second shielding layer 8 and the third shielding layer 9, between the third shielding layer 9 and the fourth shielding layer 10, and between the fourth shielding layer 10 and the fifth shielding layer 11 by the inertia of the air flow. At the same time, the parallel air holes 15 further increase the lateral thrust of the particles, increase the probability of capturing the particles between the first shielding layer 7 and the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11, further avoid the particles from causing surface flashover near the insulator, thereby ensuring the long-term operation of the DC bushing.

[0031] The inclination angle of the inclined air hole 16 is 9°, the distance between the first shielding layer 7 and the pot-type insulator 3 is 120 mm, and the concave distances between the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11 are 15 mm in sequence.

[0032] The driving electrode 4 is in the shape of a hollow truncated cone, and the inclination angle of the driving electrode 4 is 10°.

[0033] The support assembly includes a first support ring group 17 and a second support ring group 18 , and the first support ring group 17 and the second support ring group 18 are symmetrically arranged.

[0034] The first support ring group 17 and the second support ring group 18 have the same structure, and both include a first support ring 19, a second support ring 20, a third support ring 21 and a fourth support ring 22. The first support ring 19, the second support ring 20, the third support ring 21 and the fourth support ring 22 are respectively located between the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11. The first support ring 19, the second support ring 20, the third support ring 21 and the fourth support ring 22 are each provided with a plurality of groups of particle through holes 23, and the particle through holes 23 on the first support ring 19, the second support ring 20, the third support ring 21 and the fourth support ring 22 are staggered.

[0035] The first support ring 19, the second support ring 20, the third support ring 21 and the fourth support ring 22 form a support connection on the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11 to ensure the overall connection of the capacitor shielding layer 6. At the same time, the first support ring 19, the second support ring 20, the third support ring 21 and the fourth support ring 22 are all provided with particle through holes 23, through which gas and particles are circulated, and the particles are captured by the staggered particle through holes 23 to reduce escape, which is further conducive to the long-term use of the DC bushing.

[0036] The cross section of the particle through hole 23 is trapezoidal, and the larger opening side of the particle through hole 23 on the first support ring group 17 and the second support ring group 18 faces outward, further reducing the escape of particles and increasing the capture of particles.

[0037] The DC bushing based on DC GIL power transmission realizes the pressure equalization inside the tube shell 1 by setting the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11, and realizes the pressure equalization inside the tube shell 1 by staggering the concentric single height of multiple groups of shielding layers in sequence. At the same time, the setting of the first shielding layer 7, the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11 can also increase the strength of the tube shell 1, further increase the pressure bearing capacity of the DC bushing, and through the setting of the inclined air holes 16, the flow of gas drives the movement of particles, and at the same time, in combination with the repulsive force of the driving electrode 4, the repelled particles can be brought by the inertia of the airflow. The particles are inserted between the first shielding layer 7 and the second shielding layer 8, between the second shielding layer 8 and the third shielding layer 9, between the third shielding layer 9 and the fourth shielding layer 10, and between the fourth shielding layer 10 and the fifth shielding layer 11. At the same time, the parallel air holes 15 further increase the lateral thrust of the particles, and increase the capture probability of the particles between the first shielding layer 7 and the second shielding layer 8, the third shielding layer 9, the fourth shielding layer 10 and the fifth shielding layer 11. In combination with the driving of the particles by the driving electrode 4 and the setting of the particle trap 12, the particles can be better aggregated and the probability of particle capture is increased, thereby increasing the safety of the DC bushing and ensuring the long-term reliable operation of the DC bushing.

[0038] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A DC bushing for DC GIL power transmission, comprising a casing (1), characterized in that: A conductor (2) is provided at the inner central axis of the tube shell (1); a basin-type insulator (3) is provided on the outer wall of one end of the conductor (2); a driving electrode (4) is provided on one side of the basin-type insulator (3); a three-pillar insulator (5) is provided at the other end of the conductor (2); a capacitive shielding layer (6) is provided between the three-pillar insulator (5) and the driving electrode (4); and a gas transmission component for the circulation of SF6 gas is provided on the basin-type insulator (3); The capacitor shielding layer (6) comprises a first shielding layer (7), a second shielding layer (8), a third shielding layer (9), a fourth shielding layer (10) and a fifth shielding layer (11); a concentric circle structure is formed between the first shielding layer (7), the second shielding layer (8), the third shielding layer (9), the fourth shielding layer (10) and the fifth shielding layer (11); the first shielding layer (7) is connected to the inner wall of the tube shell (1); a particle trap (12) is provided on the inner wall of the end of the fifth shielding layer (11) close to the driving electrode (4); both ends of the first shielding layer (7), the second shielding layer (8), the third shielding layer (9), the fourth shielding layer (10) and the fifth shielding layer (11) are concave at equal intervals in sequence; and a support assembly is provided between the first shielding layer (7), the second shielding layer (8), the third shielding layer (9), the fourth shielding layer (10) and the fifth shielding layer (11); the basin-type insulator (3) comprises an installation A ring (13) and an insulating seat (14), wherein the insulating seat (14) is in a truncated cone shape, and the insulating seat (14) and the mounting ring (13) are integrally formed; the gas transmission component comprises parallel air holes (15) and inclined air holes (16), the mounting ring (13) has a plurality of groups of parallel air holes (15) distributed in an annular array, and the side wall of the insulating seat (14) has a plurality of groups of inclined air holes (16) distributed in an annular array; the extension lines of the central axes of the plurality of groups of parallel air holes (15) are respectively located between the first shielding layer (7) and the second shielding layer (8) and between the second shielding layer (8) and the third shielding layer (9), between the third shielding layer (9) and the fourth shielding layer (10), and between the fourth shielding layer (10) and the fifth shielding layer (11).

2. A DC bushing based on DC GIL power transmission according to claim 1, characterized in that: The inclined air hole (16) has an inclination angle of 9°, the spacing between the first shielding layer (7) and the pot-type insulator (3) is 120 mm, and the concave spacings between the first shielding layer (7), the second shielding layer (8), the third shielding layer (9), the fourth shielding layer (10) and the fifth shielding layer (11) are 15 mm.

3. A DC bushing based on DC GIL power transmission according to claim 1, characterized in that: The driving electrode (4) is in the shape of a hollow truncated cone, and the inclination angle of the driving electrode (4) is 10°.

4. A DC bushing based on DC GIL power transmission according to claim 1, characterized in that: The support assembly comprises a first support ring group (17) and a second support ring group (18), wherein the first support ring group (17) and the second support ring group (18) are symmetrically arranged.

5. A DC bushing based on DC GIL power transmission according to claim 4, characterized in that: The first support ring group (17) and the second support ring group (18) have the same structure, and both comprise a first support ring (19), a second support ring (20), a third support ring (21) and a fourth support ring (22); the first support ring (19), the second support ring (20), the third support ring (21) and the fourth support ring (22) are located respectively between the first shielding layer (7), the second shielding layer (8), the third shielding layer (9), the fourth shielding layer (10) and the fifth shielding layer (11); the first support ring (19), the second support ring (20), the third support ring (21) and the fourth support ring (22) are each provided with a plurality of groups of particle through holes (23); and the particle through holes (23) on the first support ring (19), the second support ring (20), the third support ring (21) and the fourth support ring (22) are staggered.

6. A DC bushing based on DC GIL power transmission according to claim 5, characterized in that: The cross section of the particle through hole (23) is trapezoidal, and the side with a larger opening of the particle through hole (23) on the first support ring group (17) and the second support ring group (18) faces outwards.

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