阅读说明：本技术 一种用于封闭式冲击电压发生器的均压环组件 (Grading ring assembly for closed impulse voltage generator ) 是由 刘轩东 马钰峰 张乔根 于 2020-05-28 设计创作，主要内容包括：本公开揭示了一种用于封闭式冲击电压发生器的均压环组件,包括：外均压环和多级内均压环,其中,所述外均压环连接于冲击电压发生器壳体两端的对接法兰上,所述多级内均压环均匀排列于冲击电压发生器内每级放电模块两侧的绝缘板上,通过等电位屏蔽冲击电压发生器内局部电场。本公开通过在现有封闭式冲击电压发生器中只安装外均压环的基础上沿放电模块安装内均压环,一方面能够抑制了外沿面上下端部电场,另一方面能够降低外沿面电场不均匀程度。(The present disclosure discloses a grading ring assembly for a closed impulse voltage generator, comprising: the grading ring in multistage is evenly arranged on the insulation board of every grade of discharge module both sides in the impulse voltage generator, through the interior local electric field of equipotential shielding impulse voltage generator. According to the closed surge voltage generator, the inner grading ring is installed along the discharge module on the basis that only the outer grading ring is installed in the existing closed surge voltage generator, so that electric fields at the upper end and the lower end of the outer edge surface can be restrained on the one hand, and the non-uniform degree of the electric field of the outer edge surface can be reduced on the other hand.)

1. An grading ring assembly for an enclosed surge voltage generator, comprising: an outer grading ring and a multi-stage inner grading ring, wherein,

the outer grading rings are connected to the butt flanges at the two ends of the impulse voltage generator shell,

the multistage inner grading rings are uniformly arranged on the insulating plates on two sides of each stage of discharge module in the impulse voltage generator, and local electric fields in the impulse voltage generator are shielded through equipotential.

2. The grading ring assembly of claim 1, wherein preferably, said multiple stages of inner grading rings are arranged in sequence from top to bottom along the insulating plates on two sides of each discharge module of the impulse voltage generator, wherein the first and last stages of inner grading rings are oval, and the rest of the inner grading rings are circular.

3. The grading ring assembly of claim 2 wherein the oval grading ring has a tube radius of 30mm and a width of 110mm and the circular grading ring has a tube radius of 30 mm.

4. The grading ring assembly of claim 1 wherein said outer grading ring comprises a grading ring body and a grading ring connector, said grading ring body and said grading ring connector being bolted together.

5. The grading ring assembly of claim 4 wherein said grading ring connector is an L-shaped aluminum connector.

6. The grading ring assembly of claim 1 wherein said outer grading ring has an outer ring radius of 1200mm-1250mm, a tube radius of 150mm and a cover depth of 150 mm.

Technical Field

The utility model belongs to the technical field of electric power system, a concretely designs a voltage grading ring subassembly for closed impulse generator.

Background

Because primary equipment may generate some potential insulation defects in the production and manufacturing process, and the insulation defects can be detected by field high-voltage tests, the high-voltage tests need to be carried out on newly-invested primary equipment; after primary equipment runs for a period of time, because certain faults of the equipment can be caused by the influence of the environment and some changes in the primary equipment, a high-voltage test is required to be carried out for a period of time after the primary equipment is put into operation so as to ensure the safe and stable operation of the equipment. High-voltage electrical equipment in a power system can bear the action of short-term lightning overvoltage and operation overvoltage in the operation process besides long-term working voltage, and the voltages belong to impulse voltage and can possibly bring harm to the electrical equipment. It is therefore necessary to verify the insulating or protective properties of the electrical equipment under the action of lightning voltages and operating overvoltages before it is put into use. The voltage for the test is generally full wave or chopped wave of thunder and lightning, and a surge voltage generator is used for generating the surge voltage wave. In the field of high voltage test, a surge voltage generator is a common and important high voltage test device, and is especially a main test means for industries such as power capacitors and power transformer manufacturing and high voltage test rooms.

Along with the large tracts of land construction of extra-high voltage alternating current-direct current electric wire netting, the test capacity of on-spot high-voltage testing equipment is also bigger and bigger, and to GIS and high tension cable, the capacitive load grade can reach 3000 ~ 10000 pF. The traditional open impulse voltage generator is difficult to generate the lightning impulse voltage meeting the standard due to the constraint of the inherent inductance of the traditional open impulse voltage generator, and meanwhile, the continuously improved output voltage and output energy challenge the space and flexibility of the impulse voltage generator. Therefore, the impulse voltage generator adopting a low-inductance pulse capacitor discharge circuit, an integrated compact structure and good insulating performance is the key for solving the problems. The enclosed gas insulation impulse voltage generator can greatly reduce the volume and the weight of the test device, is convenient for the transportation and the installation of the test device, improves the working efficiency and is beneficial to ensuring the field test requirement of high-capacity high-voltage primary equipment; on the other hand, the closed gas insulation structure is beneficial to reducing the influence of the external environment on the test process and improving the test reliability.

In the debugging and field test process of the closed gas insulation impulse voltage generator, high-amplitude impulse voltage can be born by the outer edge surface of the insulating outer cylinder in the moment of discharge, the geometric shape of the electrode at the flange fastening screw is relatively outstanding, local air ionization is easily caused, and meanwhile, the electric field on the surface of the insulating cylinder is distorted under the action of the vertical component of the electric field, so that flashover faults are caused on the outer wall of the epoxy insulating cylinder, and the insulation damage of the device is caused.

Disclosure of Invention

To overcome the defects in the prior art, an object of the present disclosure is to provide a grading ring assembly for a closed impulse voltage generator, which can significantly reduce the incidence rate of flashover accidents along the outer surface of the impulse voltage generator.

In order to achieve the above purpose, the present disclosure provides the following technical solutions:

an grading ring assembly for an enclosed surge voltage generator, comprising: the grading device comprises an outer grading ring and an inner grading ring, wherein the outer grading ring is connected to butt flanges at two ends of a shell of the impulse voltage generator, and the grading rings are uniformly arranged on insulating plates on two sides of each stage of discharge module in the impulse voltage generator.

Preferably, the multilevel inner equalizing rings are sequentially arranged from top to bottom along insulating plates on two sides of each stage of discharge module of the impulse voltage generator, wherein the first-stage inner equalizing ring and the last-stage inner equalizing ring are oval, and the rest of the multilevel inner equalizing rings are circular.

Preferably, the pipe radius of oval equalizer ring is 30mm, and the width is 110mm, the pipe radius of circular equalizer ring is 30 mm.

Preferably, the outer grading ring comprises a grading ring body and a grading ring connecting piece, and the grading ring body is connected with the grading ring connecting piece through a bolt.

Preferably, the grading ring connecting piece is an L-shaped aluminum connecting piece.

Preferably, the outer ring radius of the outer grading ring is 1200mm-1250mm, the pipe radius is 150mm, and the cover depth is 150 mm.

Compared with the prior art, the beneficial effect that this disclosure brought does:

1. the inner grading ring and the outer grading ring are adopted to restrain an electric field of an outer edge surface, the influence of the actual structure of the device is fully considered, and the design is reasonable.

2. The method can be directly applied to the production practice of the grading ring, and can reduce the probability of flashover accidents.

Drawings

Fig. 1 is a schematic structural diagram of a surge voltage generator provided in an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of an internal plan structure of a surge voltage generator provided in one embodiment of the present disclosure;

FIG. 3 is a schematic diagram of an outer grading ring configuration provided by one embodiment of the present disclosure;

FIG. 4 is a schematic diagram of an inner grading ring according to an embodiment of the disclosure;

FIG. 5 is a schematic diagram of a tangential electric field distribution curve of an outer edge surface of a front impulse voltage generator and a rear impulse voltage generator in optimized configuration of a grading ring according to an embodiment of the disclosure;

fig. 6 is a schematic diagram of a tangential electric field distribution curve of an outer edge surface of a front and rear impulse voltage generator with an internal grading ring according to an embodiment of the disclosure.

Detailed Description

Specific embodiments of the present disclosure will be described in detail below with reference to fig. 1 to 6. While specific embodiments of the disclosure are shown in the drawings, it should be understood that the disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

It should be noted that certain terms are used throughout the description and claims to refer to particular components. As one skilled in the art will appreciate, various names may be used to refer to a component. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. The description which follows is a preferred embodiment of the invention, but is made for the purpose of illustrating the general principles of the invention and not for the purpose of limiting the scope of the invention. The scope of the present disclosure is to be determined by the terms of the appended claims.

To facilitate an understanding of the embodiments of the present disclosure, the following detailed description is to be considered in conjunction with the accompanying drawings, and the drawings are not to be construed as limiting the embodiments of the present disclosure.

Fig. 1 is a block-type closed gas-insulated impulse voltage generator, as shown in fig. 1, the impulse voltage generator is divided into 3 sections, and comprises an epoxy insulated inflatable casing 1, a butt flange 2, an external grading ring 3 for shielding an electric field at an end part, and a movable base 4.

Fig. 2 is a sectional view of the internal structure of a single-stage impulse voltage generator, and a core part of the generator, namely a multi-stage charging and discharging module, is packaged in an epoxy insulating gas-filled housing and comprises a pulse capacitor 5, a gas switch 6, a charging resistor 7 and an isolation resistor 8. Every two groups of pulse capacitors and one gas switch form a primary discharging module.

The outer equalizing ring in the impulse voltage generator is optimized, and the problem of simply configuring the outer equalizing ring is solved by adding the inner equalizing ring.

In one embodiment, the present disclosure provides an grading ring assembly for an enclosed surge voltage generator, comprising: the grading ring in the multistage is evenly arranged on the insulation plates on both sides of each stage of discharge module in the impulse voltage generator.

In this embodiment, the purpose of setting up the equalizer ring is in order to shield the field intensity of impulse voltage generator both ends flange to flange and fastening screw department, and in the prior art, though can reduce the field intensity to a certain extent through installing outer equalizer ring, the field intensity still is in higher level. Because the inner core of the impulse voltage generator is provided with a plurality of metal connecting pieces in different shapes, a local electric field concentration area can appear in the discharging process, the problem can be solved by installing the inner equalizing ring in the impulse voltage generator, the multi-stage inner equalizing ring can effectively shield a high field intensity area in each stage of discharging module in the impulse voltage generator, and therefore discharging in the impulse voltage generator can be avoided; because the geometric shape of the inner equalizing ring is regular, a plurality of middle electrodes are equivalently added, and the axial and radial electric fields of the insulating cylinder of the impulse voltage generator along the surface can be adjusted. Therefore, the inner grading ring can be installed to shield the inner machine core on one hand and improve the surface electric field on the other hand.

In another embodiment, as shown in fig. 3, the outer grading ring includes a grading ring body 11 and a grading ring connector 12, and the grading ring body 11 is connected to the grading ring connector 12 through a bolt 13.

In this embodiment, the grading ring connecting piece 12 is an "L" shaped aluminum connecting piece, one end of which is connected to the grading ring body 11 through a hexagon bolt, and the other end of which is connected to the butting flanges at the two ends of the impulse voltage generator. The position of the grading ring body can be adjusted by adjusting the length of the grading ring connecting piece.

In another embodiment, the outer ring radius of the outer grading ring is 1200mm-1250mm, the pipe radius is 150mm, and the cover depth is 150 mm.

In this embodiment, since the outer grading ring is fixed to the docking flange through the connecting piece, as shown in fig. 3, the radius of the outer insulating cylinder is 1040mm, the radius R of the outer ring of the outer grading ring should be larger than the radius of the outer insulating cylinder, and meanwhile, the smaller the radius R of the outer ring, the better the shielding effect on the electric field at the end portion is; for the radius r of the outer ring pipe, the radius is not suitable to be too large for processing, but the larger the radius of the pipe is, the thicker the ring is, the better the shielding effect is, so the above numerical values are the results in view of the electric field shielding effect and the design processing aspect; for the cover depth of the outer grading ring, the embodiment is calculated through experiments, and when the cover depth is larger than the length of the screw, the electric field intensity of the outer end part is the minimum.

In another embodiment, as shown in fig. 4, the multiple stages of inner grading rings are sequentially arranged from top to bottom along the insulating plates on two sides of each stage of discharge module of the impulse voltage generator, wherein the first and last stages of inner grading rings 14 are oval, and the remaining inner grading rings 15 are round.

In this embodiment, the larger the cross-sectional area of the inner grading ring is, the better the electric field shielding effect at the flange fastening screw is, because the space between the inner core and the outer insulating cylinder of the closed impulse voltage generator is limited, the size of the inner grading ring is not so large, and in order to better reduce the field intensity at the screws at the two end portions of the outer edge surface, the first-stage inner grading ring located at the topmost end of each stage of discharge module of the impulse voltage generator and the last-stage inner grading ring located at the bottommost end are longitudinally stretched into an oval shape on a circular basis, so as to increase the cross-sectional area thereof, thereby being capable of playing the effect of suppressing the electric field. The design of the rest grading rings in each stage is circular, so that the grading rings are convenient to install on one hand, and the circular design is adopted to maximize the insulation distance between the rings, so that the discharge phenomenon between the rings is not easy to occur.

In another embodiment, the oval grading ring has a tube radius of 30mm and a width of 110mm, and the circular grading ring has a tube radius of 30 mm.

In this embodiment, the inner grading ring is installed between the inner core and the outer insulating cylinder of the impulse voltage generator, the radius of the inner core is 820mm, and the inner diameter of the outer insulating cylinder is 930mm, so that the size adjustment range of the inner grading ring is limited. For oval grading rings, in order to ensure that sufficient insulation distance exists between the internal grading rings, the oval grading rings are convenient to install, and the width of the oval grading rings is not too large.

FIG. 5 is a comparison graph of tangential electric field distribution curves of the outer edge surfaces of the impulse voltage generator with the inner equalizing ring and the outer equalizing ring installed and without the inner equalizing ring and the outer equalizing ring, as shown in FIG. 5, through simulation calculation, after the inner equalizing ring and the outer equalizing ring are installed, the field intensities of the upper end part and the lower end part of the outer edge surface of the impulse voltage generator are obviously reduced, and are respectively reduced to 0.55kV/mm and 0.39kV/mm from 6.83kV/mm and 1.40 kV/mm. Therefore, according to the method, after the grading rings are optimally configured, the electric field distribution of the outer edge surface can be effectively improved, and the surface flashover field intensity is reduced.

FIG. 6 is a comparison graph of tangential electric field distribution curves of the outer edge surface of the impulse voltage generator when the inner equalizing ring and the outer equalizing ring are installed and when only the outer equalizing ring is installed, as shown in FIG. 6, through simulation calculation, after the outer equalizing ring is installed, the field intensities of the upper end part and the lower end part of the outer edge surface of the impulse voltage generator are reduced to 2.46kV/mm and 0.94kV/mm from 6.83kV/mm and 1.40kV/mm respectively, and after the multi-stage equalizing ring is installed inside, the maximum field intensities of the upper end part and the lower end part of the outer edge surface are further reduced to 0.55kV/mm and 0.39 kV/mm. The tangential field intensity of the middle section of the outer edge surface is always lower than 1kV/mm, the field intensity value is slightly raised after the grading ring is installed, the field intensity value is still at a lower level, and the distribution of the electric field of the middle section of the outer edge surface is more uniform after the inner grading ring and the outer grading ring are installed. Therefore, according to the method, after the grading rings are optimally configured, the electric field distribution of the outer edge surface can be effectively improved, and the surface flashover field intensity is reduced.

The foregoing describes the general principles of the present application in conjunction with specific embodiments, however, it is noted that the advantages, effects, etc. mentioned in the present application are merely examples and are not limiting, and they should not be considered essential to the various embodiments of the present application. Furthermore, the foregoing disclosure of specific details is for the purpose of illustration and description and is not intended to be limiting, since the foregoing disclosure is not intended to be exhaustive or to limit the disclosure to the precise details disclosed.

The foregoing description has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit embodiments of the application to the form disclosed herein. While a number of example aspects and embodiments have been discussed above, those of skill in the art will recognize certain variations, modifications, alterations, additions and sub-combinations thereof.