CN111834066A - Novel trapezoidal double-pole arc extinguishing insulator - Google Patents
Novel trapezoidal double-pole arc extinguishing insulator Download PDFInfo
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- CN111834066A CN111834066A CN201910305801.1A CN201910305801A CN111834066A CN 111834066 A CN111834066 A CN 111834066A CN 201910305801 A CN201910305801 A CN 201910305801A CN 111834066 A CN111834066 A CN 111834066A
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- extinguishing
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B17/00—Insulators or insulating bodies characterised by their form
- H01B17/42—Means for obtaining improved distribution of voltage; Protection against arc discharges
- H01B17/46—Means for providing an external arc-discharge path
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Abstract
The invention discloses a novel trapezoidal double-pole arc extinguishing insulator which mainly comprises an insulator main body, an upper electrode and a lower electrode; the insulator main body is hollow and is provided with a plurality of insulating partition plates so that a plurality of independent backflushing pouring arc extinguishing chambers are formed in the insulator main body; each backflushing pouring arc extinguishing cavity is internally provided with a backflushing device which is arranged in a stepped spiral mode in the insulator main body, the backflushing openings of every two adjacent backflushing devices are opposite in direction, a wall electrode is arranged on an insulating partition plate between every two adjacent backflushing devices, the top of the backflushing device located below is connected with one surface of the wall electrode, and the bottom of the backflushing device located above is connected with the other surface of the wall electrode. The lightning protection device effectively prevents the problem of flashover of the lightning protection device, reduces the lightning trip-out rate of power equipment, protects power facilities, improves the reliability of a power grid, and is favorable for power safety production.
Description
Technical Field
The invention belongs to insulators for power transmission and distribution overhead lines, and relates to a novel trapezoidal double-pole arc-extinguishing insulator.
Background
The insulator is a special insulating control and can play an important role in an overhead transmission line. Early-age insulators are mostly used for telegraph poles, and a plurality of disc-shaped insulators are hung at one end of a high-voltage wire connecting tower which is gradually developed, are used for increasing creepage distance and are usually made of glass or ceramics. The insulator should not fail due to various electromechanical stresses caused by changes in environmental and electrical loading conditions, otherwise the insulator will not function significantly and will compromise the service and operational life of the entire line.
The main function of the insulator is to achieve electrical insulation and mechanical fixation, for which various electrical and mechanical properties are specified. The method aims at the aspects of development, process, materials, test method, aging problem, mechanical property, brittle failure problem, umbrella group digging, high altitude problem and the like of the composite insulator, wherein the aging problem seriously affects the lightning resistance level of a power transmission line, and the insulator generates flashover and generates single-phase short circuit fault to cause a trip accident under the serious condition.
Disclosure of Invention
The invention aims to provide a novel trapezoidal double-pole arc-extinguishing insulator aiming at the problem that insulator aging causes arc surface flashover in the prior art.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a novel trapezoidal double-pole arc extinguishing insulator mainly comprises an insulator main body, an upper electrode and a lower electrode; the upper end and the lower end of the insulator main body are both provided with openings, the interior of the insulator main body is hollow, and a plurality of insulating partition plates are longitudinally arranged along the insulator main body, so that a plurality of independent backflushing pouring arc extinguishing chambers are formed in the insulator main body; each backflushing pouring arc extinguishing cavity is provided with a backflushing device, the backflushing devices are arranged in the insulator main body in a stepped spiral mode, and the backflushing openings of every two adjacent backflushing devices are opposite in direction (namely the backflushing devices in the insulator main body are arranged in the same direction at intervals); wall electrodes are arranged on the insulating partition plate between every two adjacent backflushing devices, the top of the backflushing device positioned below is connected with one surface of the wall electrode, and the bottom of the backflushing device positioned above is connected with the other surface of the wall electrode; the top of the backflushing device at the uppermost end of the insulator main body is connected with the upper electrode, and the bottom of the backflushing device at the lowermost end of the insulator main body is connected with the lower electrode.
In the invention, the backflushing devices are arranged in a spiral step shape, only one backflushing device is arranged in each backflushing pouring arc extinguishing cavity, the backflushing arc extinguishing can be carried out on the electric arc in sequence, and the wall electrode is arranged, so that the flashover path of the electric arc can be limited. Meanwhile, the recoil openings of every two adjacent recoil devices are arranged oppositely, so that the electric arc can be effectively recoiled and extinguished no matter the lightning arc flashover from top to bottom or from bottom to top.
The invention further discloses that the backflushing device mainly comprises a backflushing pipe and a lightning receptor; one end of the recoil pipe is opened, and the other end of the recoil pipe is fixedly provided with the lightning receptor, so that the recoil device becomes a semi-closed pipe fitting which is hollow inside and is opened at one end and closed at the other end; the lightning receptor is connected with the adjacent wall electrode.
The invention further discloses that an opening of the back flushing pipe is provided with an arc guiding ring; the arc guide ring is connected with the adjacent wall electrode.
The invention further discloses that the cross section of the insulator main body is of a honeycomb structure.
Further, a plurality of skirt edges are arranged on the outer surface of the novel trapezoidal double-pole arc-extinguishing insulator. The skirt edge is added outside the device structure, the creepage distance is enhanced, and electric arc creeping discharge is avoided.
The invention further discloses that the novel trapezoidal double-pole arc-extinguishing insulator is fixedly arranged on the cross arm or the overhead conductor through the connecting hardware fitting.
The invention further discloses that the wall electrode adopts an arc guide electrode plate or a compression arc extinguishing tube. The inside of compression arc-extinguishing pipe be equipped with the arc guide ball. The compression arc-extinguishing tube adopts a ceramic tube.
The invention further illustrates that the inner wall of the insulator main body is mainly made of high-strength and strong-pressure-resistant non-conductive materials, such as alloy ceramics, rare earth ceramics, graphene-ceramic composite materials, organic ceramics and other non-conductive materials; the insulating partition plate is made of a high-strength and strong-pressure-resistant non-conductive material, such as synthetic silicon rubber, rare earth glass, graphene glass and other non-conductive materials; the wall electrode material is a metal or nonmetal with strong conductivity, such as copper, aluminum, tungsten, nickel, iron, graphite and the like.
The technical principle of the invention is as follows:
this novel trapezoidal bipolar arc extinguishing insulator is installed on the horizontal pole or overhead conductor, is flashover air channel in the middle of this trapezoidal bipolar arc extinguishing insulator, through insulating cooperation, among the arc extinguishing device in trapezoidal bipolar arc extinguishing insulator interior was got into to the electric arc that the thunderbolt overvoltage that produces when thunderbolt shaft tower or lightning conductor formed.
The electric arc is a plasma with elastic deformation, after the electric arc enters the backflushing device through the arc guide ring, due to the limitation of the backflushing pipe wall, when the electric arc enters the initial end of the backflushing pipe, the density, the speed and the temperature are increased, so that the pressure in the pipe is increased, finally, a pressure explosion effect is generated, the electric arc impacts a lightning receptor at the bottom of the backflushing pipe, the electric arc is subjected to reverse elasticity at the bottom of the blocked backflushing pipe, the advancing direction of most of the electric arc is changed by 180 degrees, and the rebounded electric arc acts on an outer electric arc at an inlet due to the fact that the speed, the density and the pressure are larger, so that the electric arc at. The rest part of the electric arc enters the next recoil pipe due to the coulomb force of the wall electrode, and the process is repeated.
The back-flushing pipe in this patent is a narrow pipe filling channel, which is the only channel for the electric arc to enter the device. A variety of physical changes occur during perfusion.
1. The arc plasma is elastically deformed. When the arc plasma enters the inlet of the back flushing pipe, the physical shape is changed firstly, a coarse arc is changed into an ultrafine arc, the radial pressure is changed into the axial pressure, and the spraying speed is accelerated during the arc back flushing due to the back flushing effect of the narrow pipe.
2. The arc temperature rise effect is exacerbated. After the electric arc is thinned, the cross-sectional area of the electric arc is reduced according to the formula
The arc resistance will increase substantially. Due to lightningThe arc is often used as a constant current source in practical empirical work according to a formula
It is known that although the impact time is only a few microseconds, the overall energy increases and the packing temperature in the recoil tube increases.
Arc radiation, convection and conduction are three ways of energy loss, and because heat cannot be released in a closed pipeline, namely an exogenous plugging environment, the arc is blocked, heat can be generated only, heat dissipation cannot be realized, so that blocking temperature rise can be generated, and the temperature in the pipeline is continuously increased.
3. The pressure explosion effect increases sharply. When the temperature is gradually increased, the accumulation of the electric arc is increased, the pressure explosion effect is further aggravated, and the electric arc spraying strength is larger.
When electric arc gets into the recoil device from the arrester, because the recoil pipe is very thin, thick thunder and lightning electric arc can be deformed into slender electric arc when getting into the recoil pipe, is full of whole pipeline, and the pipeline can produce the effort to electric arc and finally can form the pressure and explode the effect, blocks passing through of follow-up electric arc, produces the arc and cuts. And a small part of electric arc enters the next recoil pipe under the coulomb force action of the arc guide ring and the arc guide piece, and the process is repeated.
In contrast to multiple chambers
(1) And (5) the durability is compared. The gas production material added into the multi-cavity needs to be baked at high temperature to produce gas, so that the gas production material in the multi-cavity arc extinguishing device is consumed in a high-temperature environment, and the durability of the multi-cavity is poor; the pouring material adopted by the invention has no consumption factor, does not need to extinguish arc through a gas generation mechanism, and has better durability.
(2) And (5) arc extinguishing effect comparison. When electric arcs pass through every two adjacent electrodes in the multi-cavity chamber, a condensation polar effect is generated, namely the temperature of the electric arcs under the adjacent electrodes is low, gas production effect is poor due to baking of gas production materials by low-temperature electric arcs, and arc extinguishing effect is poor due to contradiction between the condensation polar effect and arc extinguishing formed by baking of gas production at high temperature; the invention adopts a narrow tube pouring mechanism, the electric arc collision generates huge arc extinguishing energy, and the self energy of the electric arc and the collision arc extinguishing are utilized, so that the arc extinguishing effect is excellent.
(3) And (5) comparing arc extinguishing sensitivity. According to the durability and the arc extinguishing effect, as the durability of the multi-cavity is influenced by high temperature, the generated gas is influenced by the electrode condensation pole effect, namely the low-temperature arc baking capability is extremely low, the contradiction between the condensation pole effect and the high-temperature baked generated gas forming arc extinguishing is formed, the arc extinguishing effect is poor when a small arc passes through, the multi-cavity can only act correctly when a larger arc passes through the multi-cavity, and the relay protection action is caused by the circulation of the large arc, namely, a trip accident exists, so the arc extinguishing sensitivity of the multi-cavity is not ideal; in the invention, no matter large electric arcs or small electric arcs exist, the electric arcs are only required to enter the invention to generate a perfusion mechanism, and the sensitivity is higher.
(4) And comparing the operation modes. According to the sensitivity analysis, the action of the multi-cavity is influenced by external factors such as a system operation mode, short-circuit current and the like, and an arc extinguishing blind area exists, so that the multi-cavity lightning protection matching is very difficult; the invention has no influence of external factors such as system operation mode, short-circuit current and the like.
The invention has the advantages and beneficial effects as follows:
(1) an arc path is restrained and controlled, the arc is consistent with an arc extinguishing channel, and the harm of arc drift is eliminated;
(2) the back-flushing devices in the back-flushing perfusion arc-extinguishing cavities act on the electric arcs to realize mutual isolation of different electric arc sections, and the electric arcs are cut off at the flashers in each back-flushing assembly and are not easy to re-ignite;
(3) the wall electrode in the clapboard outside the back-flushing pouring arc extinguishing cavity can effectively disperse the energy of the electric arc, so that the whole electric arc is broken into parts;
(4) the recoil device in the recoil perfusion arc extinguishing cavity is not influenced by temperature and electrodynamic force in the arc extinguishing process; the arc extinguishing sensitivity is high;
(5) the electric arc is extinguished in the impact arc extinguishing section and destroys the power frequency arc establishing channel, and the relay protection device is ensured not to be perceived;
(6) the invention can directly replace the insulator string on the transmission line, not only has the original insulation function, but also has the lightning protection and arc extinguishing functions, has wide application range and is not influenced by the arrangement of the conducting wire, the tower type and the polar effect.
(7) The lightning protection device is effectively prevented from flashover, the lightning trip-out rate of the power equipment is reduced, the power facilities are protected, the reliability of a power grid is improved, and the power safety production is facilitated.
Drawings
FIG. 1 is a schematic view of the installation structure of the trapezoidal bipolar quenching insulator of the present invention;
FIG. 2 is a schematic view of the internal partial structure of the trapezoidal bipolar arc-extinguishing insulator of the present invention;
FIG. 3 is a schematic cross-sectional view of a trapezoidal bipolar quenching insulator of the present invention;
FIG. 4 is a schematic view of the recoil assembly of the present invention.
Wherein, each icon and the corresponding part name are as follows:
1-insulator main body, 2-upper electrode, 3-lower electrode, 4-insulating partition board, 5-backflushing pouring arc extinguishing chamber, 6-backflushing device, 7-wall electrode, 8-skirt edge, 61-backflushing tube, 62 lightning arrester, 611-arc guide ring.
Detailed Description
The present invention will be described in further non-limiting detail with reference to the following preferred embodiments and accompanying drawings.
Example 1:
as shown in the figure, the novel trapezoidal double-pole arc-extinguishing insulator mainly comprises an insulator main body 1, an upper electrode 2 and a lower electrode 3; the upper end and the lower end of the insulator main body 1 are both provided with openings, the interior of the insulator main body 1 is hollow, and a plurality of insulating partition plates 4 are longitudinally arranged along the insulator main body 1, so that a plurality of independent backflushing pouring arc extinguishing chambers 5 are formed in the insulator main body 1; a recoil device 6 is arranged in each recoil filling arc extinguishing cavity 5, the recoil devices 6 are arranged in the insulator main body 1 in a stepped spiral mode, and the directions of recoil openings of the recoil devices 6 adjacent to each other in pairs are opposite; the wall electrodes 7 are arranged on the insulating partition plates 4 between every two adjacent backflushing devices 6, the top of the backflushing device positioned below is connected with one surface of the wall electrode 7, and the bottom of the backflushing device positioned above is connected with the other surface of the wall electrode 7; the top of the backflushing device at the uppermost end of the insulator main body 1 is connected with the upper electrode 2, and the bottom of the backflushing device at the lowermost end of the insulator main body 1 is connected with the lower electrode 3.
The backflushing device 6 mainly comprises a backflushing pipe 61 and a lightning receptor 62; one end of the recoil pipe 61 is open, and the other end is fixedly provided with a lightning receptor 62, so that the recoil device 6 becomes a semi-closed pipe fitting with a hollow interior, an open end and a closed end; the lightning receptor 62 is connected to the adjacent wall electrode 7.
An opening of the recoil pipe 61 is provided with an arc guide ring 611; the arc guiding ring 611 is connected with the adjacent wall electrode 7.
The cross section of the insulator main body 1 is of a honeycomb structure.
The novel trapezoidal double-pole arc extinguishing insulator is fixedly installed on the cross arm or the overhead conductor through a connecting hardware fitting.
The wall electrode 7 adopts an arc-conducting electrode plate.
Example 2:
this example differs from example 1 in that: the outer surface of the insulator main body 1 is provided with a plurality of skirt edges 8.
Example 3:
this example differs from example 1 in that: the wall electrode 7 adopts a compression arc extinguishing tube.
Example 4:
this example differs from example 3 in that: the inside of compression arc-extinguishing pipe be equipped with the arc guide ball.
In the practical application process, the novel trapezoidal double-pole arc-extinguishing insulator is arranged on a cross rod or an overhead conductor, and an electric arc formed by lightning overvoltage generated when a tower or a lightning conductor is struck by lightning enters an arc-extinguishing device in the trapezoidal double-pole arc-extinguishing insulator.
When lightning strikes on a transmission line or a circuit to generate induced lightning overvoltage, lightning current at a high-voltage end of a lightning protection device is caused to start to pass through a high-voltage electrode, an electric arc can be pulled by the high-voltage electrode to enter the device to be backflushed into an arc extinguishing chamber 5, after the electric arc enters a backflushing device 6, the electric arc is limited by a backflushing pipe wall, the density, the speed and the temperature are increased to cause the increase of the pressure in the pipe and finally generate a pressure explosion effect, the electric arc impacts a flasher 62 at the bottom of the backflushing pipe 61, the electric arc is subjected to reverse elasticity at the bottom of the blocked backflushing pipe, the advancing direction of most of the electric arc is changed by 180 degrees, and the rebounded electric arc is subjected to external electric arc at an inlet due to the fact that the speed, the density and the pressure. And a small part of electric arc enters the next recoil pipe due to the coulomb force of the wall electrode, and the process is repeated.
When thunderbolt shaft tower or transmission line lightning conductor, cause lightning protection device flashover low-voltage end to begin to have lightning current to pass through the low-voltage electrode, the electric arc can draw through the low-voltage electrode and get into this device recoil filling arc-extinguishing chamber 5 inside, because the inside diameter is very little in the recoil pipe device 6, thick lightning electric arc can be deformed into slender electric arc when getting into the recoil pipe, is full of whole pipeline, and the pipeline can produce the effect of exploding by the pressure that can finally form to the electric arc, blocks passing through of follow-up electric arc, produces the arc and cuts. The remaining portion of the arc enters the next recoil tube due to the coulomb force of the arc runner 71 and the arc runner, and the process is repeated.
Finally, it should be pointed out that: the above examples are only for illustrating the technical solutions of the present invention, and are not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (8)
1. A novel trapezoidal double-pole arc extinguishing insulator mainly comprises an insulator main body (1), an upper electrode (2) and a lower electrode (3); the method is characterized in that: the upper end and the lower end of the insulator main body (1) are provided with openings, the interior of the insulator main body is hollow, and a plurality of insulating partition plates (4) are longitudinally arranged along the insulator main body (1) to form a plurality of independent backflushing pouring arc extinguishing chambers (5) in the insulator main body (1); each backflushing pouring arc extinguishing cavity (5) is internally provided with a backflushing device (6), the backflushing devices (6) are arranged in the insulator main body (1) in a stepped spiral mode, and the backflushing opening directions of every two adjacent backflushing devices (6) are opposite; wall electrodes (7) are arranged on the insulating partition plates (4) between every two adjacent backflushing devices (6), one surface of each wall electrode (7) is connected with the top of the backflushing device positioned below, and the other surface of each wall electrode is connected with the bottom of the backflushing device positioned above; the top of the backflushing device at the uppermost end of the insulator main body (1) is connected with the upper electrode (2), and the bottom of the backflushing device at the lowermost end of the insulator main body (1) is connected with the lower electrode (3).
2. The novel trapezoidal bipolar arc-extinguishing insulator according to claim 1, is characterized in that: the backflushing device (6) mainly comprises a backflushing pipe (61) and a lightning receptor (62); one end of the recoil pipe (61) is opened, and the other end of the recoil pipe is fixedly provided with the lightning receptor (62), so that the recoil device (6) becomes a semi-closed pipe fitting which is hollow inside, and is opened at one end and closed at the other end; the lightning receptor (62) is connected with the adjacent wall electrode (7).
3. The novel trapezoidal bipolar arc-extinguishing insulator according to claim 2, characterized in that: an opening of the backflushing pipe (61) is provided with an arc guiding ring (611); the arc guiding ring (611) is connected with the adjacent wall electrode (7).
4. The novel trapezoidal bipolar arc-extinguishing insulator according to claim 1, is characterized in that: the cross section of the insulator main body (1) is of a honeycomb structure.
5. The novel trapezoidal bipolar arc-extinguishing insulator according to claim 1, is characterized in that: the outer surface of the insulator main body (1) is provided with a plurality of skirt edges (8).
6. The novel trapezoidal bipolar arc-extinguishing insulator according to claim 1, is characterized in that: the novel trapezoidal double-pole arc extinguishing insulator is fixedly installed on the cross arm or the overhead conductor through a connecting hardware fitting.
7. The novel trapezoidal bipolar arc-extinguishing insulator according to claim 1, is characterized in that: the wall electrode (7) adopts an arc guide electrode plate or a compression arc extinguishing tube.
8. The novel trapezoidal bipolar arc-extinguishing insulator according to claim 6, is characterized in that: the inside of compression arc-extinguishing pipe be equipped with the arc guide ball.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910305801.1A CN111834066A (en) | 2019-04-16 | 2019-04-16 | Novel trapezoidal double-pole arc extinguishing insulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910305801.1A CN111834066A (en) | 2019-04-16 | 2019-04-16 | Novel trapezoidal double-pole arc extinguishing insulator |
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| Publication Number | Publication Date |
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| CN111834066A true CN111834066A (en) | 2020-10-27 |
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|---|---|---|---|
| CN201910305801.1A Pending CN111834066A (en) | 2019-04-16 | 2019-04-16 | Novel trapezoidal double-pole arc extinguishing insulator |
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| CN (1) | CN111834066A (en) |
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- 2019-04-16 CN CN201910305801.1A patent/CN111834066A/en active Pending
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