Device for testing flashover discharge characteristics of surface of dry-type direct-current bushing under alternating-current and direct-current voltage

Abstract

The invention provides a device for testing flashover discharge characteristics of the surface of a dry-type direct-current bushing under alternating-current and direct-current voltages. The device comprises an angle-adjustable base, a first insulating cylinder, a second insulating cylinder and a particle release mechanism, the base is provided with an inclined top face and adjusts the inclination degree of the top face. The first insulating cylinder and the second insulating cylinder are obliquely arranged on the top surface of the base; a to-be-tested DC bushing is clamped between the first insulating cylinder and the second insulating cylinder, the first end of the to-be-tested DC bushing is arranged in the first insulating cylinder, and the second end of the to-be-tested DC bushing is arranged in the second insulating cylinder; the particle release mechanism is arranged in the first insulating cylinder and is electrically connected with a conductive tube at the first end of the DC bushing to be tested and the end part, far away from the second insulating cylinder, of the first insulating cylinder, so as to release test particles into the first insulating cylinder; the end, away from the second insulating cylinder, of the first insulating cylinder is electrically connected with a direct-current voltage generator. According to the invention, the discharge parameters of the first insulating cylinder and the second insulating cylinder can be detected, and the test of discharge characteristics is realized.

Description

Technical Field

[0001] The invention relates to the technical field of high-voltage insulating bushing detection equipment, and in particular to a flashover discharge characteristic testing device under AC and DC voltages on the surface of a dry-type DC bushing. Background Art

[0002] The transformer bushing is the main insulating device outside the transformer box. The lead wires of the transformer winding must pass through the insulating bushing to insulate the lead wires and between the lead wires and the transformer casing, and at the same time, it plays the role of fixing the lead wires. The transformer bushing is an important and most risky component on the transformer, especially in UHV projects. Dry-type DC bushings such as glue-impregnated paper DC bushings are easy to use, safe to operate, and have excellent explosion resistance and will not explode. They are increasingly favored by users. However, there is currently no suitable test device to test the AC and DC flashover discharge characteristics of the gas-solid insulation interface of the DC bushing under the influence of different metal and non-metallic particles on the core surface, core surface grinding and coating conditions, and insulating gas humidity. Summary of the invention

[0003] In view of this, the present invention proposes a device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltages, aiming to solve the problem that the AC and DC flashover discharge characteristics of DC bushings cannot be tested in the prior art.

[0004] The present invention provides a device for testing flashover discharge characteristics of a dry-type DC bushing surface under AC and DC voltages. The device comprises: an angle-adjustable base, a first insulating cylinder, a second insulating cylinder and a particle releasing mechanism; wherein the base has a top surface in an inclined state, and the base is used to adjust its own angle to adjust the inclination of the top surface; the first insulating cylinder and the second insulating cylinder are arranged opposite to each other and are both inclinedly arranged on the top surface of the base; the middle part of the DC bushing to be tested is clamped between the first insulating cylinder and the second insulating cylinder, the first end of the DC bushing to be tested is placed in the first insulating cylinder, and the second end of the DC bushing to be tested is placed in the second insulating cylinder; the particle releasing mechanism is arranged in the first insulating cylinder and is electrically connected to a conductive tube at the first end of the DC bushing to be tested and an end of the first insulating cylinder away from the second insulating cylinder, and is used to release test particles into the first insulating cylinder; the end of the first insulating cylinder away from the second insulating cylinder is used to be electrically connected to a DC voltage generator.

[0005] Furthermore, in the above-mentioned dry-type DC bushing surface flashover discharge characteristic test device under AC and DC voltage, the particle release mechanism includes: a mounting seat, a first clamp, a second clamp and a driving mechanism; wherein the mounting seat is arranged adjacent to the end of the insulating jacket at the first end of the DC bushing to be tested, and the mounting seat is respectively provided with a mounting hole and an operating hole in the longitudinal direction, the conductive tube is passed through the mounting hole and connected to the mounting seat, and the mounting seat is electrically connected to the end of the first insulating tube away from the second insulating tube; the first clamp is arranged in the operating hole and the first end extends to the outside of the mounting seat; the second clamp is rotatably arranged in the operating hole and the first end extends to the outside of the mounting seat, and the first end of the first clamp and the first end of the second clamp are used to clamp the test particles; the driving mechanism is arranged on the mounting seat and partially placed in the operating hole, and is used to drive the second clamp to rotate so that the first end of the second clamp is away from the first clamp, thereby releasing the test particles.

[0006] Furthermore, in the above-mentioned dry-type DC bushing surface flashover discharge characteristic test device under AC and DC voltage, the driving mechanism includes: a telescopic device and a return structure; wherein the telescopic device is arranged on the mounting seat, and the telescopic end of the telescopic device is placed in the operating hole and contacts with the second clamping jaw, and is used to push the second clamping jaw to rotate when the telescopic end is extended, so that the first end of the second clamping jaw is away from the first clamping jaw; the return structure is arranged between the second clamping jaw and the first clamping jaw, and is used to return the second clamping jaw when the telescopic end is retracted.

[0007] Furthermore, in the above-mentioned dry-type DC bushing surface flashover discharge characteristic test device under AC and DC voltage, the first jaw and the second jaw are both L-shaped, the end of the first end of the first jaw extends to the outside of the mounting seat, and the second end of the first jaw is arranged opposite to the telescopic end; the end of the first end of the second jaw extends to the outside of the mounting seat, the bending part of the second jaw is hinged in the operating hole, and the second end of the second jaw is placed between the second end of the first jaw and the telescopic end; the return structure is a return spring, and the return spring is arranged between the second end of the first jaw and the second end of the second jaw.

[0008] Furthermore, in the above-mentioned dry DC bushing surface flashover discharge characteristic testing device under AC and DC voltage, the particle release mechanism also includes: a mounting bolt; wherein the mounting seat is radially provided with a threaded hole, the threaded hole is vertically connected to the mounting hole; the mounting bolt is screwed into the threaded hole and abuts against the conductive tube.

[0009] Furthermore, the above-mentioned dry-type DC bushing surface flashover discharge characteristic test device under AC and DC voltage also includes: a first shielding cover; wherein the first shielding cover is arranged in the first insulating tube and clamped between the mounting seat and the end of the first insulating tube away from the second insulating tube; the end of the conductive tube after passing through the mounting seat and the telescopic device are both placed in the first shielding cover.

[0010] Furthermore, the above-mentioned flashover discharge characteristic testing device under AC and DC voltage on the surface of the dry-type DC bushing also includes: a grading ring and / or a second shielding cover; wherein, the grading ring is placed outside the first insulating tube and connected to the end of the first insulating tube away from the second insulating tube, and the grading ring is also connected to the cable between the first insulating tube and the DC voltage generator; the second shielding cover is arranged in the second insulating tube and is sleeved on the outside of the conductive tube at the second end of the DC bushing to be tested.

[0011] Furthermore, in the above-mentioned dry DC bushing surface flashover discharge characteristic testing device under AC and DC voltage, a plurality of lifting legs are arranged at the bottom of the base, and each lifting leg is used to adjust its own height to adjust the inclination degree of the top surface of the base; and / or a plurality of walking wheels are arranged at the bottom of the base.

[0012] Furthermore, the above-mentioned dry DC bushing surface flashover discharge characteristic testing device under AC and DC voltage also includes: a detection device; wherein the detection device is arranged outside the first insulating tube and the second insulating tube, and is used for the bushing surface discharge characteristics.

[0013] Furthermore, the above-mentioned dry-type DC bushing surface flashover discharge characteristic test device under AC and DC voltage also includes: a control device; wherein the detection device also includes: a plurality of partial discharge instruments and a camera device; each partial discharge instrument is respectively arranged on the outside of the first insulating cylinder and the outside of the second insulating cylinder, and each partial discharge instrument is used to detect the discharge phase characteristics and the discharge amount; the control device is electrically connected to each partial discharge instrument and the camera device, and is used to control the camera device to shoot the discharge state inside the first insulating cylinder and the second insulating cylinder when the partial discharge instrument detects discharge.

[0014] In the present invention, the first insulating tube and the second insulating tube are arranged opposite to each other and obliquely arranged on the inclined top surface of the base, the two ends of the DC bushing to be tested are respectively placed in the first insulating tube and the second insulating tube, the particle releasing mechanism releases the test particles into the first insulating tube, the DC voltage generator inputs a high voltage to the conductive tube through the end of the first insulating tube, and the first insulating tube and the second insulating tube are filled with insulating gas, so that the discharge parameters of the first insulating tube and the second insulating tube can be detected, and the test of the discharge characteristics is realized, and the AC and DC flashover discharge characteristics of the gas-solid insulation interface under different parameters can be tested by changing the parameters of the DC bushing to be tested, which solves the problem that the AC and DC flashover discharge characteristics of the DC bushing cannot be tested in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0016] Figure 1 A schematic diagram of the structure of a device for testing flashover discharge characteristics of a dry-type DC bushing surface under AC and DC voltages provided by an embodiment of the present invention;

[0017] Figure 2 A schematic diagram of the main structure of a device for testing flashover discharge characteristics of a dry-type DC bushing surface under AC and DC voltages provided by an embodiment of the present invention;

[0018] Figure 3 A left-side structural schematic diagram of a device for testing flashover discharge characteristics of a dry-type DC bushing surface under AC and DC voltages provided by an embodiment of the present invention;

[0019] Figure 4 for Figure 3 Schematic diagram of the cross-sectional structure at AA in the middle;

[0020] Figure 5 A right-side structural schematic diagram of a device for testing flashover discharge characteristics of a dry-type DC bushing surface under AC and DC voltages provided by an embodiment of the present invention;

[0021] Figure 6 A schematic structural diagram of a particle release mechanism in a device for testing flashover discharge characteristics of a dry-type DC bushing surface under AC and DC voltages provided by an embodiment of the present invention;

[0022] Figure 7 A schematic diagram of the main structure of a particle release mechanism in a device for testing flashover discharge characteristics of a dry-type DC bushing surface under AC and DC voltages provided by an embodiment of the present invention;

[0023] Figure 8 for Figure 7 Schematic diagram of the cross-sectional structure at BB in the middle;

[0024] Fig. 9 for Figure 7 Schematic diagram of the cross-section structure at CC in the middle;

[0025] Fig.10 A schematic structural diagram of a DC bushing to be tested in a device for testing flashover discharge characteristics of a dry DC bushing under AC and DC voltages provided by an embodiment of the present invention;

[0026] Fig.11 A structural block diagram of a device for testing flashover discharge characteristics of a dry-type DC bushing surface under AC and DC voltages provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0028] See also Figures 1 to 10 , the figure shows the preferred structure of the flashover discharge characteristic test device of the dry-type DC bushing surface under AC and DC voltage in this embodiment. As shown in the figure, the flashover discharge characteristic test device of the dry-type DC bushing surface under AC and DC voltage includes: an angle-adjustable base 1, a first insulating cylinder 2, a second insulating cylinder 3 and a particle release mechanism 4. Among them, the base 1 has a top surface in an inclined state, and the base 1 is used to adjust its own angle to adjust the angle of the top surface of the base 1, and then adjust the degree of inclination of the top surface of the base 1. Specifically, the base 1 is in the shape of a rectangular parallelepiped, and the top surface of the base 1 is in an inclined state, and the top surface is from the first side ( Figure 2 right side shown) to the second side ( Figure 2 The left side shown) slopes gradually downward.

[0029] Preferably, the bottom of the base 1 ( Figure 2 The lower part of the base 1 is provided with a plurality of lifting legs 9. Specifically, the bottom of the base 1 is in a horizontal state, and the lifting legs 9 are arranged at intervals at the bottom of the base 1, preferably evenly distributed. Each lifting leg 9 is used to adjust its own height to adjust the inclination of the top surface of the base 1. Specifically, a plurality of threaded holes are provided at intervals at the bottom of the base 1, and the outer wall of each lifting leg 9 is provided with threads. Each lifting leg 9 is screwed with the corresponding threaded hole. By screwing the lifting legs 9, the height of the lifting legs 9 extending to the bottom of the base 1 is adjusted, that is, the overall inclination of the base 1 is adjusted, thereby realizing the adjustment of the inclination of the top surface of the base 1. In specific implementation, each lifting leg 9 can adjust the inclination angle of the base 1 between 25° and 40°.

[0030] Preferably, a plurality of running wheels 10 are provided at the bottom of the base 1, and each running wheel 10 is arranged at intervals at the bottom of the base 1, and preferably evenly distributed. Specifically, there are four running wheels 10, and the four running wheels 10 are distributed in a rectangular shape at the bottom of the base 1.

[0031] Preferably, a plurality of lifting legs 9 are provided at the bottom of the base 1, and each lifting leg 9 is used to adjust its own height to adjust the inclination of the top surface of the base 1; and / or, a plurality of walking wheels 10 are provided at the bottom of the base 1.

[0032] The first insulating tube 2 and the second insulating tube 3 are coaxially arranged and arranged opposite to each other. There is a preset distance between the first insulating tube 2 and the second insulating tube 3. The preset distance can be determined according to actual conditions, and this embodiment does not impose any restrictions on this. The first insulating tube 2 and the second insulating tube 3 are both parallel to the top surface of the base 1, and the first insulating tube 2 and the second insulating tube 3 are both inclinedly arranged on the top surface of the base 1. Specifically, the first insulating tube 2 and the second insulating tube 3 are arranged up and down, the first insulating tube 2 is fixed on the top surface of the base 1 through a support, and the second insulating tube 3 is also fixed on the top surface of the base 1 through a support. The first insulating tube 2 corresponds to the first side of the base 1, and the second insulating tube 3 corresponds to the second side of the base 1.

[0033] In specific implementation, the first insulating tube 2 and the second insulating tube 3 can be transparent organic glass tubes, which are convenient for observing the inside. The first insulating tube 2 and the second insulating tube 3 can be made of acrylic casting plates with a thickness of 30mm. During the test, the organic glass tube is filled with insulating gas with a working pressure of 1MPa.

[0034] The middle part of the DC bushing 5 to be tested is sandwiched between the first insulating tube 2 and the second insulating tube 3, the first end of the DC bushing 5 to be tested is placed in the first insulating tube 2, and the second end of the DC bushing 5 to be tested is placed in the second insulating tube 3. Specifically, the DC bushing 5 to be tested is parallel to the top surface of the base 1, and the DC bushing 5 to be tested is connected to both the first insulating tube 2 and the second insulating tube 3.

[0035] See also Fig.10 The DC bushing 5 to be tested includes: a conductive tube 51, an insulating jacket 52 and a bushing flange 53. The insulating jacket 52 is sleeved on the outside of the conductive tube 51, and both ends of the conductive tube 51 extend out of the insulating jacket 52, that is, the insulating jacket 52 does not completely wrap the conductive tube 51, but wraps most of the conductive tube 51, while the two ends of the conductive tube 51 are not wrapped by the insulating jacket 52. The bushing flange 53 is sleeved on the middle part of the insulating jacket 52, and a connection hole is opened on the bushing flange 53, which is used for crimping connection of the ground wire.

[0036] In specific implementation, the DC bushing 5 to be tested is a dry DC bushing, which may be a glue-impregnated paper DC bushing, or a dry DC bushing with different insulation forms such as glue-impregnated fiber and adhesive paper, and this embodiment does not impose any limitation on this.

[0037] Both ends of the first insulating tube 2 are open ends, and both ends of the first insulating tube 2 are provided with flange plates to seal the first insulating tube 2, and a seal is provided at the connection between each end of the first insulating tube 2 and the corresponding flange plate for sealing. The end of the first insulating tube 2 away from the second insulating tube 3 is recorded as the first end ( Figure 2 The flange plate at the first end of the first insulating tube 2 is denoted as the first flange plate 14, and the first flange plate 14 can be a metal circular plate.

[0038] Both ends of the second insulating tube 3 are also open ends, and both ends of the second insulating tube 3 are provided with flange plates to seal the second insulating tube 3, and a sealing member is provided at the connection between each end of the second insulating tube 3 and the corresponding flange plate for sealing. The end of the second insulating tube 3 away from the first insulating tube 2 is recorded as the first end ( Figure 2 The flange plate at the first end of the second insulating tube 3 is marked as a second flange plate 15, and the second flange plate 15 can be a transparent organic glass plate.

[0039] The first insulating tube 2 and the second insulating tube 3 are connected to both sides of the bushing flange 53, that is, the bushing flange 53 is placed between the first insulating tube 2 and the second insulating tube 3, and the two ends of the bushing flange 53 are respectively connected to the flange plates at the two opposite ends of the first insulating tube 2 and the second insulating tube 3, and a seal is provided at the connection for sealing. The bushing flange 53 in the DC bushing 5 to be tested is placed between the first insulating tube 2 and the second insulating tube 3, and the rest of the DC bushing 5 to be tested except the bushing flange 53 is placed in the first insulating tube 2 and the second insulating tube 3, respectively.

[0040] The particle release mechanism 4 is disposed in the first insulating tube 2, and the particle release mechanism 4 is connected to the first end ( Figure 4 The conductive tube 51 at the upper end (shown in FIG. 1 ) and the end of the first insulating tube 2 away from the second insulating tube 3 are electrically connected, and the particle release mechanism 4 is used to release the test particles 19 into the first insulating tube 2. Specifically, in the first insulating tube 2, the end of the conductive tube 51 outside the insulating jacket 52 is connected to the particle release mechanism 4, and the particle release mechanism 4 is also electrically connected to the first end of the first insulating tube 2.

[0041] In specific implementation, the test particles 19 may be metal particles or non-metal particles, and this embodiment does not impose any limitation on this.

[0042] The end of the first insulating tube 2 away from the second insulating tube 3 is used to be electrically connected to the DC voltage generator, that is, the first end of the first insulating tube 2 is electrically connected to the DC voltage generator. Specifically, the first flange plate 14 is a metal circular plate, and the first flange plate 14 is electrically connected to the particle release mechanism 4 and the DC voltage generator through cables, so the DC voltage generator inputs a high voltage to the conductive tube 51 through the first flange plate 14 and the particle release mechanism 4.

[0043] More specifically, a high-voltage wire hole 18 is provided on the outer side of the first flange plate 14, the first end of the cable is pressed on the high-voltage wire hole 18 by bolts, the second end of the cable is connected to the DC voltage generator, and a corrugated tube is provided on the outer side of the cable.

[0044] Preferably, the flashover discharge characteristic test device of the dry DC bushing surface under AC and DC voltage also includes: a voltage grading ring 7. The voltage grading ring 7 is placed outside the first insulating tube 2, and the voltage grading ring 7 is connected to the end of the first insulating tube 2 away from the second insulating tube 3, that is, the voltage grading ring 7 is connected to the first flange plate 14 at the first end of the first insulating tube 2, and the voltage grading ring 7 is also connected to the cable between the first insulating tube 2 and the DC voltage generator. Specifically, a plurality of flange bolts are provided on the voltage grading ring 7, and each flange bolt is connected to the corrugated tube outside the cable to eliminate the discharge caused by the external test circuit of the test device.

[0045] Preferably, the flashover discharge characteristic test device under AC and DC voltage on the surface of dry-type DC bushing further comprises: a second shielding cover 8. The second shielding cover 8 is arranged inside the second insulating cylinder 3, and the second shielding cover 8 is sleeved on the second end ( Figure 4 Specifically, in the second insulating tube 3, the second shielding cover 8 is sleeved on the outside of the end of the conductive tube 51 outside the insulating jacket 52, and the second shielding cover 8 is used to prevent tip discharge and interference during testing.

[0046] During specific implementation, the second shielding cover 8 is a metal cover.

[0047] A connecting ring is provided at the center of one end of the second shielding cover 8 facing the first insulating tube 2, and the connecting ring is connected to the second shielding cover 8 through a metal connecting rib, the connecting ring is clamped with the conductive tube 51, and the connecting ring is tightened by bolts to achieve fixed connection of the second shielding cover 8.

[0048] Preferably, the flashover discharge characteristic testing device for the surface of a dry-type DC bushing under AC and DC voltages also includes: a grading ring 7 and / or a second shielding cover 8; wherein the grading ring 7 is placed outside the first insulating tube 2 and connected to the end of the first insulating tube 2 away from the second insulating tube 3, and the grading ring 7 is also connected to the cable between the first insulating tube 2 and the DC voltage generator; the second shielding cover 8 is arranged in the second insulating tube 3 and is sleeved on the outside of the conductive tube 51 at the second end of the DC bushing 5 to be tested.

[0049] During specific implementation, the DC bushing 5 to be tested may be a DC bushing of normal size, or may be a shortened and reversed DC bushing.

[0050] It can be seen that in this embodiment, the first insulating tube 2 and the second insulating tube 3 are arranged opposite to each other and obliquely arranged on the inclined top surface of the base 1, the two ends of the DC bushing 5 to be tested are respectively placed in the first insulating tube 2 and the second insulating tube 3, the particle release mechanism 4 releases the test particles 19 into the first insulating tube 2, the DC voltage generator inputs a high voltage to the conductive tube 51 through the end of the first insulating tube 2, and the first insulating tube 2 and the second insulating tube 3 are filled with insulating gas. In this way, the discharge parameters of the first insulating tube 2 and the second insulating tube 3 can be detected, and the test of the discharge characteristics is realized. By changing the parameters of the DC bushing 5 to be tested, the AC and DC flashover discharge characteristics of the gas-solid insulation interface under different parameters can be tested, which solves the problem that the AC and DC flashover discharge characteristics of the DC bushing cannot be tested in the prior art.

[0051] See also Figures 1 to 9 In the above embodiment, the particle release mechanism 4 includes: a mounting seat 41, a first clamping jaw 42, a second clamping jaw 43 and a driving mechanism 44. The mounting seat 41 is arranged adjacent to the end of the insulating jacket 52 at the first end of the DC bushing 5 to be tested. Specifically, in the first insulating cylinder 2, the conductive tube 51 extends to the outside of the insulating jacket 52, and the mounting seat 41 is arranged adjacent to and in contact with the end of the insulating jacket 52. The mounting seat 41 can be a metal seat.

[0052] The mounting seat 41 is arranged along the longitudinal direction ( Figure 8 The mounting seat 41 is provided with a mounting hole 411 and an operating hole 412 (in the direction from top to bottom shown in FIG. 1 ), and the conductive tube 51 is passed through the mounting hole 411, and the end of the conductive tube 51 is placed outside the mounting seat 41, and the conductive tube 51 is connected to the mounting seat 41. Specifically, the mounting hole 411 and the operating hole 412 both penetrate the mounting seat 41 in the longitudinal direction of the mounting seat 41, wherein the mounting hole 411 is placed at the center of the mounting seat 41, and the operating hole 412 is placed on one side of the mounting hole 411.

[0053] See also Fig. 9 Preferably, the particle release mechanism 4 further comprises: a mounting bolt. Wherein, the mounting seat 41 is radially ( Fig. 9 A threaded hole 413 is provided (from left to right in the figure), and the threaded hole 413 is perpendicular to and communicates with the mounting hole 411. The mounting bolt is screwed into the threaded hole 413, and the end of the mounting bolt abuts against the conductive tube 51, so that the conductive tube 51 and the mounting seat 41 are relatively fixed.

[0054] In specific implementation, there are two threaded holes 413 that are arranged opposite to each other. Correspondingly, there are also two mounting bolts. The two mounting bolts correspond to the two threaded holes 413 one by one. Each mounting bolt is screwed into the corresponding threaded hole 413, and the ends of the two mounting bolts are both in contact with the conductive tube 51.

[0055] The mounting seat 41 is electrically connected to the end of the first insulating tube 2 away from the second insulating tube 3. Specifically, the first flange plate 14 at the first end of the first insulating tube 2 is connected to the side of the mounting seat 41 facing the first flange plate 14 through a cable. In specific implementation, a wire pressing hole 414 is provided on the side of the mounting seat 41 facing the first flange plate 14. The cable is crimped into the wire pressing hole 414, and the mounting seat 41 is connected to the first flange plate 14 through the cable. Since the first flange plate 14 is connected to the DC voltage generator through the cable, the DC voltage generator pressurizes the first flange plate 14, thereby introducing a high potential into the mounting seat 41, and then applying a high voltage to the conductive tube 51.

[0056] The first clamping jaw 42 is disposed in the operating hole 412. The first clamping jaw 42 is fixed in the operating hole 412. Moreover, the first end ( Figure 8 Specifically, the first end of the first clamping jaw 42 extends from the operating hole 412 to the outside of the side of the mounting base 41 facing the insulating jacket 52.

[0057] The second clamping jaw 43 is rotatably disposed in the operating hole 412, that is, the second clamping jaw 43 is rotatable in the operating hole 412. The first end ( Figure 8 Specifically, the first end of the second clamping jaw 43 extends from the operation hole 412 to the outside of the side of the mounting base 41 facing the insulating jacket 52. There is a gap between the first end of the first clamping jaw 42 and the first end of the second clamping jaw 43 to clamp the test particle 19.

[0058] The driving mechanism 44 is disposed on the mounting base 41 , and part of the driving mechanism 44 is placed in the operating hole 412 . The driving mechanism 44 is used to drive the second clamping jaw 43 to rotate so that the first end of the second clamping jaw 43 is away from the first end of the first clamping jaw 42 , thereby releasing the test particle 19 .

[0059] The driving mechanism 44 may include: a telescopic device 441 and a return structure 442. The telescopic device 441 is arranged on the mounting seat 41, specifically, the telescopic device 441 is arranged on a side of the mounting seat 41 facing the first flange plate 14. The telescopic end 4411 of the telescopic device 441 is placed in the operating hole 412, and the telescopic end 4411 is in contact with the second clamping jaw 43. When the telescopic end 4411 is extended, the telescopic end 4411 pushes the second clamping jaw 43 to rotate, so that the first end of the second clamping jaw 43 is away from the first end of the first clamping jaw 42, thereby releasing the test particle 19. Preferably, the telescopic device 441 is an electric telescopic device.

[0060] The return structure 442 is arranged between the second clamping jaw 43 and the first clamping jaw 42. The return structure 442 is used to return the second clamping jaw 43 when the telescopic end 4411 of the telescopic device 441 retracts, that is, the first end of the second clamping jaw 43 is close to the first end of the first clamping jaw 42, so that the first end of the first clamping jaw 42 and the first end of the second clamping jaw 43 clamp the test particle 19.

[0061] The first clamping jaw 42 and the second clamping jaw 43 are both L-shaped, the end of the first end of the first clamping jaw 42 extends out of the mounting seat 41, and the second end of the first clamping jaw 42 is arranged opposite to the telescopic end 4411. Specifically, the telescopic device 441 is placed above the operating hole 412, the telescopic end 4411 of the telescopic device 441 is placed in the operating hole 412 and can be extended or shortened in the operating hole 412, and the telescopic end 4411 of the telescopic device 441 corresponds to the second end of the first clamping jaw 42.

[0062] The end of the first end of the second clamping jaw 43 extends out of the mounting seat 41, and the bending part of the second clamping jaw 43 is hinged in the operating hole 412 so that the second clamping jaw 43 can rotate around the bending part. The second end of the second clamping jaw 43 is substantially parallel to the second end of the first clamping jaw 42, and the second end of the second clamping jaw 43 is placed between the second end of the first clamping jaw 42 and the telescopic end 4411.

[0063] The return structure 442 is a return spring, which is arranged between the second end of the first clamp 42 and the second end of the second clamp 43, that is, the first end of the return spring is connected to the second end of the first clamp 42, and the second end of the return spring is connected to the second end of the second clamp 43.

[0064] See also Figure 8 When the return spring is in the original state, the return spring pushes the second end of the second clamping claw 43 toward the telescopic end 4411 of the telescopic device 441 ( Figure 8The first end of the second clamping jaw 43 is inclined upward (as shown), so that the first end of the second clamping jaw 43 approaches the first end of the first clamping jaw 42 to clamp the test particle 19. When the test particle 19 is released, the telescopic end 4411 of the telescopic device 441 extends, and the telescopic end 4411 pushes the second end of the second clamping jaw 43 to move toward the second end of the first clamping jaw 42, and the second clamping jaw 43 squeezes the return spring, so that the return spring is compressed, and the second end of the second clamping jaw 43 moves toward the second end of the first clamping jaw 42 ( Figure 8 The first end of the second clamping jaw 43 is tilted downward as shown in the figure, at this time, the first end of the second clamping jaw 43 is away from the first end of the first clamping jaw 42 to release the test particle 19. After releasing the test particle 19, the telescopic end 4411 of the telescopic device 441 retracts, and the telescopic end 4411 no longer pushes the second end of the second clamping jaw 43. Under the elastic restoring force of the return spring, the return spring pushes the second end of the second clamping jaw 43, so that the second end of the second clamping jaw 43 tilts toward the telescopic end 4411 of the telescopic device 441, so that the first end of the second clamping jaw 43 approaches the first end of the first clamping jaw 42 to clamp the next test particle 19.

[0065] In a specific implementation, the operation hole 412 is provided with a blocking portion 16 at one end facing the insulating jacket 52, and the blocking portion 16 is provided from a first side ( Figure 8 right side shown) to the second side ( Figure 8 The first clamping jaw 42 is provided at the blocking portion 16, and the first clamping jaw 42 is provided at the left side of the blocking portion 16, and a gap is provided between the blocking portion 16 and the side wall of the second side of the operation hole 412, and the gap is used for the first end of the first clamping jaw 42 and the first end of the second clamping jaw 43 to pass through. The first clamping jaw 42 is clamped at the blocking portion 16, and specifically, the bending part of the first clamping jaw 42 is attached to the end of the blocking portion 16, and the first clamping jaw 42 is fixedly connected to the blocking portion 16.

[0066] In order to ensure the stability of the connection between the first clamping jaw 42 and the operating hole 412, an extension portion 17 is vertically provided at the end of the second end of the first clamping jaw 42. The extension portion 17 is perpendicular to the second end of the first clamping jaw 42, and the extension portion 17 is attached to the side wall of the first side of the operating hole 412.

[0067] When the telescopic device 441 is an electric telescopic device, the particle release mechanism 4 further includes a battery pack 443. The battery pack 443 is disposed on a side of the mounting seat 41 facing the first flange plate 14, and the battery pack 443 and the telescopic device 441 are located on the same side of the mounting seat 41, and the battery pack 443 supplies power to the telescopic device 441.

[0068] In a specific implementation, the telescopic device 441 is a telescopic solenoid valve. The power supply mode of the battery pack 443 is a 18650 lithium battery.

[0069] It can be seen that in this embodiment, the particle releasing mechanism 4 has a simple structure and is easy to implement.

[0070] See also Figure 4 , Figures 6 to 9 In the above embodiment, the flashover discharge characteristic test device under AC and DC voltage on the surface of dry-type DC bushing further includes: a first shielding cover 6. The first shielding cover 6 is arranged inside the first insulating cylinder 2, and the first shielding cover 6 is clamped between the mounting seat 41 and the end of the first insulating cylinder 2 away from the second insulating cylinder 3, that is, the first shielding cover 6 is clamped between the mounting seat 41 and the first flange plate 14, and the first shielding cover 6 is connected to the first flange plate 14. The first shielding cover 6 is a voltage grading cover, and its material must be metal material, usually aluminum alloy material.

[0071] The end of the conductive tube 51 after passing through the mounting seat 41 and the telescopic device 441 are both placed in the first shielding cover 6. Specifically, in the first insulating cylinder 2, after the conductive tube 51 passes through the mounting hole 411 of the mounting seat 41, the end of the conductive tube 51 is placed outside the mounting seat 41 and the telescopic device 441 are both placed in the first shielding cover 6.

[0072] During specific implementation, the battery pack 443 , the end of the conductive tube 51 and the telescopic device 441 are all placed in the first shielding cover 6 .

[0073] It can be seen that in this embodiment, a first shielding cover 6 made of metal is arranged in the first insulating tube 2. The first shielding cover 6 is arranged outside the end of the conductive tube 51 to prevent tip discharge and interference during testing.

[0074] See also Fig.11 In the above embodiments, the flashover discharge characteristic test device for the dry-type DC bushing surface under AC and DC voltages further includes: a detection device. The detection device is arranged outside the first insulating cylinder 2 and the second insulating cylinder 3, and is used to detect the bushing surface discharge characteristics, which may include: discharge phase characteristics and discharge amount.

[0075] The detection device includes: a plurality of partial discharge instruments 11 and a camera device 12. Among them, each partial discharge instrument 11 is respectively arranged outside the first insulating tube 2 and outside the second insulating tube 3, and each partial discharge instrument 11 is used to detect the discharge phase characteristics and discharge amount. Specifically, each partial discharge instrument 11 can be a high-frequency partial discharge instrument. A partial discharge instrument 11 is arranged outside the first insulating tube 2, and a partial discharge instrument 11 is also arranged outside the second insulating tube 3, and each partial discharge instrument 11 is wrapped outside the first insulating tube 2 or outside the second insulating tube 3.

[0076] The camera device 12 is used to photograph the discharge state inside the first insulating tube 2 and the second insulating tube 3 to record the discharge process.

[0077] The flashover discharge characteristic test device under AC and DC voltage on the surface of dry-type DC bushing also includes: a control device 13. The control device 13 is electrically connected to each partial discharge instrument 11 and the camera device 12. The control device 13 is used to control the camera device 12 to shoot the discharge state inside the first insulating tube 2 and the second insulating tube 3 when the partial discharge instrument 11 detects the discharge value.

[0078] It can be seen that in this embodiment, when the DC bushing 5 to be tested is tested, the partial discharge instrument 11 detects the discharge phase characteristics and the discharge amount, and when the discharge is detected, the camera device 12 photographs the discharge state inside the first insulating cylinder 2 and the second insulating cylinder 3, and records the discharge process. In this way, the DC bushing 5 to be tested can be accurately tested, thereby improving the accuracy of the test.

[0079] See also Figures 1 to 10 The use process of the flashover discharge characteristic test device under AC and DC voltage on the surface of dry DC bushing is introduced: the test particle 19 is clamped between the second end of the first clamp 42 and the second end of the second clamp 43, and the insulating gas is filled into the first insulating tube 2 and the second insulating tube 3, and the working pressure is 1MPa. The DC voltage generator is connected to the first flange plate 14, and then a plurality of partial discharge instruments 11 and a camera device 12 are installed. Then, the DC voltage generator introduces a high potential to the mounting seat 41 by pressurizing the first flange plate 14, and then applies a high voltage to the conductive tube 51. The telescopic device 441 is started, and the second end of the second clamp 43 is pressed downward by the telescopic end 4411 of the telescopic device 441, and the second clamp 43 squeezes the return spring, so that the return spring is compressed, and the second end of the second clamp 43 is tilted toward the second end of the first clamp 42. At this time, the first end of the second clamp 43 is away from the first end of the first clamp 42 to release the test particle 19. After the test particles 19 are released, the test particles 19 contact the insulating jacket 52 of the DC bushing 5 to be tested, and the partial discharge is detected by the partial discharge instrument 11. When the partial discharge instrument 11 detects the discharge, the camera device 12 takes a picture.

[0080] In specific implementation, when testing the AC / DC flashover discharge characteristics of the gas-solid insulation interface of the DC bushing 5 to be tested, the surface polishing and coating state of the DC bushing 5 to be tested can be changed, the humidity of the filled insulating gas can be changed, and other parameters can be changed to test the discharge characteristics under the influence of different parameters.

[0081] During the test, the lifting legs 9 are adjusted to adjust the tilt angle of the base 1, so as to test the AC and DC flashover discharge characteristics of the gas-solid insulation interface after the test particles 19 fall at different angles.

[0082] In summary, in this embodiment, the first insulating tube 2 and the second insulating tube 3 are arranged opposite to each other and obliquely arranged on the inclined top surface of the base 1, the two ends of the DC bushing 5 to be tested are respectively placed in the first insulating tube 2 and the second insulating tube 3, the particle release mechanism 4 releases the test particles 19 into the first insulating tube 2, the DC voltage generator inputs a high voltage to the conductive tube 51 through the end of the first insulating tube 2, and the first insulating tube 2 and the second insulating tube 3 are filled with insulating gas. In this way, the discharge parameters of the first insulating tube 2 and the second insulating tube 3 can be detected, and the discharge characteristics test is realized. By changing the parameters of the DC bushing 5 to be tested, the AC and DC flashover discharge characteristics of the gas-solid insulation interface under different parameters can be tested, that is, the AC and DC flashover discharge characteristics of the gas-solid insulation interface under the influence of different core surface metal and non-metal particles, core surface polishing and coating conditions, and insulating gas humidity can be tested.

[0083] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0084] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0085] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltage, characterized in that: include: An angle-adjustable base (1), a first insulating cylinder (2), a second insulating cylinder (3) and a particle release mechanism (4); wherein: The base (1) has a top surface in an inclined state, and the base (1) is used to adjust its own angle to adjust the degree of inclination of the top surface; The first insulating tube (2) and the second insulating tube (3) are arranged opposite to each other and are both arranged obliquely on the top surface of the base (1); The middle part of the DC bushing (5) to be tested is sandwiched between the first insulating cylinder (2) and the second insulating cylinder (3), the first end of the DC bushing (5) to be tested is placed in the first insulating cylinder (2), and the second end of the DC bushing (5) to be tested is placed in the second insulating cylinder (3); The particle release mechanism (4) is arranged in the first insulating tube (2) and is electrically connected to the conductive tube (51) at the first end of the DC bushing (5) to be tested and the end of the first insulating tube (2) away from the second insulating tube (3), and is used for releasing test particles into the first insulating tube (2); The end of the first insulating tube (2) away from the second insulating tube (3) is used for being electrically connected to a DC voltage generator.

2. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltage according to claim 1 is characterized in that: The particle release mechanism (4) comprises: a mounting seat (41), a first clamping jaw (42), a second clamping jaw (43) and a driving mechanism (44); wherein: The mounting seat (41) is arranged adjacent to the end of the insulating jacket (52) at the first end of the DC bushing (5) to be tested, the mounting seat (41) is provided with a mounting hole (411) and an operating hole (412) in the longitudinal direction, the conductive tube (51) is passed through the mounting hole (411) and connected to the mounting seat (41), and the mounting seat (41) is electrically connected to the end of the first insulating tube (2) away from the second insulating tube (3); The first clamping claw (42) is disposed in the operating hole (412) and a first end thereof extends outward from the mounting seat (41); The second clamping jaw (43) is rotatably disposed in the operating hole (412) and a first end thereof extends out of the mounting seat (41), and the first end of the first clamping jaw (42) and the first end of the second clamping jaw (43) are used to clamp the test particle (19); The driving mechanism (44) is arranged on the mounting seat (41) and is partially placed in the operating hole (412), and is used to drive the second clamping jaw (43) to rotate so that the first end of the second clamping jaw (43) is away from the first clamping jaw (42), thereby releasing the test particle (19).

3. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltage according to claim 2 is characterized in that: The driving mechanism (44) comprises: a telescopic device (441) and a return structure (442); wherein: The telescopic device (441) is arranged on the mounting seat (41), and the telescopic end (4411) of the telescopic device (441) is placed in the operating hole (412) and in contact with the second clamping jaw (43), and is used to push the second clamping jaw (43) to rotate when the telescopic end (4411) is extended, so that the first end of the second clamping jaw (43) is away from the first clamping jaw (42); The return structure (442) is arranged between the second clamping jaw (43) and the first clamping jaw (42), and is used to return the second clamping jaw (43) when the telescopic end (4411) retracts.

4. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltage according to claim 3 is characterized in that: The first clamping jaw (42) and the second clamping jaw (43) are both L-shaped, the end of the first end of the first clamping jaw (42) extends out of the mounting seat (41), and the second end of the first clamping jaw (42) is arranged opposite to the telescopic end (4411); The end of the first end of the second clamping jaw (43) extends out of the mounting seat (41), the bending part of the second clamping jaw (43) is hinged in the operating hole (412), and the second end of the second clamping jaw (43) is placed between the second end of the first clamping jaw (42) and the telescopic end (4411); The return structure (442) is a return spring, and the return spring is arranged between the second end of the first clamping jaw (42) and the second end of the second clamping jaw (43).

5. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltage according to claim 2 is characterized in that: The particle release mechanism (4) further comprises: a mounting bolt; wherein: The mounting seat (41) is provided with a threaded hole (413) in a radial direction, and the threaded hole (413) is vertically connected to the mounting hole (411); The mounting bolt is threadedly connected to the threaded hole (413) and abuts against the conductive tube (51).

6. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltage according to claim 3 is characterized in that: Also includes: A first shielding cover (6); wherein: The first shielding cover (6) is arranged in the first insulating tube (2) and is clamped between the mounting seat (41) and an end of the first insulating tube (2) away from the second insulating tube (3); The end of the conductive tube (51) after passing through the mounting seat (41) and the telescopic device (441) are both placed in the first shielding cover (6).

7. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltage according to claim 1 is characterized in that: Also includes: A pressure equalizing ring (7) and / or a second shielding cover (8); wherein: The voltage-grading ring (7) is placed outside the first insulating tube (2) and connected to the end of the first insulating tube (2) away from the second insulating tube (3); the voltage-grading ring (7) is also connected to the cable between the first insulating tube (2) and the DC voltage generator; The second shielding cover (8) is arranged in the second insulating cylinder (3) and is sleeved on the outside of the conductive tube (51) at the second end of the DC bushing (5) to be tested.

8. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltages according to claim 1 is characterized in that: A plurality of lifting legs (9) are provided at the bottom of the base (1), and each of the lifting legs (9) is used to adjust its own height so as to adjust the inclination of the top surface of the base (1); and / or, A plurality of running wheels (10) are arranged at the bottom of the base (1).

9. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltage according to claim 1, characterized in that: Also includes: Detection device; wherein, The detection device is arranged outside the first insulating tube (2) and the second insulating tube (3) and is used to detect the creeping discharge characteristics of the bushing.

10. The device for testing flashover discharge characteristics of dry-type DC bushing surface under AC and DC voltages according to claim 9, characterized in that: Also includes: A control device (13); wherein The detection device further comprises: a plurality of partial discharge instruments (11) and a camera device (12); Each of the partial discharge instruments (11) is respectively arranged outside the first insulating cylinder (2) and outside the second insulating cylinder (3), and each of the partial discharge instruments (11) is used to detect discharge phase characteristics and discharge amount; The control device (13) is electrically connected to each of the partial discharge instruments (11) and the camera device (12), and is used to control the camera device (12) to photograph the discharge state inside the first insulating cylinder (2) and inside the second insulating cylinder (3) when the partial discharge instrument (11) detects discharge.

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