JP3476812B1 - Continuous lightning arrester - Google Patents

Abstract

A non-continuous lightning arrester having a simple structure, having instantaneous interruption performance, improving breaking strength, or improving insulation performance, is practically usable, inexpensive, and excellent in discharge withstand capability. A non-continuous flow lightning arrester according to the present invention is a lightning arrester that obtains a breaking performance by discharging inside a small-diameter tube. The relationship of the length L (mm) of the small diameter tube acting as a chamber is L> 8
0xS raised to the power of 0.2, and if necessary, the inner wall portion a of the small-diameter tube 1 is made of a reinforcing material such as FRP, and the tip of the small-diameter tube 1 is made of a reinforcing material such as FRP. Inner wall a
The discharge electrode 4 is fixed to the rear surface of the discharge electrode 4 from the rear end of the small-diameter tube 1 as necessary.
The outer insulation 5 and the insulating wall of the small-diameter tube 1 are provided in close contact with the outer surface of the distal end of the back electrode 3 mounted closely to the outer surface of the small-diameter tube 1 up to a position slightly ahead of the position where is located. And 2 are integrally molded with the same polymer compound.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous current lightning arrester which prevents dielectric breakdown of a power line due to a lightning surge.

[0002]

2. Description of the Related Art As a conventional follow-current cut-off arc horn, the arc horn electrodes are flashed through the inside of an insulating cylinder by an abnormal voltage such as lightning surge, and then insulated. Utilizing the action of high-pressure gas heated by arc heat from the inside of the cylinder, a device for interrupting the continuous current of the one-wire ground fault current and short-circuit current, that is, the fault current, within half a cycle is provided. It is known (for example, Patent Document 1 and Patent Document 2).

However, in all of these, a current due to an abnormal voltage such as a lightning surge and a subsequent fault current flow, and when the fault current is a short circuit current, the energy passing through the device is Since it is much larger than that caused by lightning surge current or one-line ground fault current, the insulating cylinder may be broken or the inner diameter of the insulating cylinder may be expanded, resulting in deterioration of the continuous current interruption performance of the device. There is a problem that the number of repeated uses is reduced.

Further, in a lightning arrester having a similar follow-current blocking function, a follow-current blocking performance is enhanced by utilizing a gap between an insulating tube and a filler which is a gas releasing substance inserted in the insulating tube. In order to relieve the axial stress caused by the pressure rise in the insulating tube, the 3
A discharge type lightning arrester that employs a thread screw system is known (for example, Japanese Utility Model Publication No. 39-16968).

However, this emission arrester has a problem that the structure of the filler portion and the electrode portion is complicated and the cost is high.

Further, in the conventional discharge type lightning arrester, since the material for generating arc extinguishing gas by arc heat is used in the arc extinguishing chamber, not only the consumption of the material cannot be avoided but also the high extinction Since it was difficult to select a strong material, the arc-extinguishing chamber often expands, resulting in reduced arc-extinguishing performance and equipment damage.The tip of the back electrode of the emission arrester is made of interfacial insulation made of different substances. Therefore, there is a problem that the insulation performance is not high.

Under such circumstances, although there is a track record of use of a continuous current interrupting type arc horn with a limited number of operations in an actual line, a continuous current type arc horn without an operation number limitation is currently used. The mainstream is the use of surge arresters that use characteristic elements such as ZnO elements, but not the use of emission arresters or
Lightning arresters using characteristic elements such as elements are not only expensive, but also the lightning striker's energy
When the value is large, there is a problem that the ZnO element is burned out.

[0008]

[Patent Document 1] Japanese Patent Laid-Open No. 8-321372

[Patent Document 2] Japanese Patent Laid-Open No. 2001-102149

[Patent Document 3] Japanese Utility Model Publication No. 39-16968

[0009]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems described in the prior art. It has a simple structure and is capable of providing instantaneous breaking performance, improving breaking strength, or insulating. It is an object of the present invention to provide a continuous-current lightning arrester that is practically usable, inexpensive, and excellent in discharge withstand capability by improving performance.

[0010]

The continuous-current lightning arrester of the present invention is a lightning arrester which obtains breaking performance by internal discharge of a small diameter pipe.
m2) and the length L (mm) of the small diameter tube that functions as an arc extinguishing chamber
Is set to L> 80 × S raised to the power of 0.2.

Further, the inner wall portion of the small-diameter tube is formed of a reinforcing material such as FRP, and the discharge electrode is fixed to the inner wall portion of the tip portion of the small-diameter tube formed of the reinforcing material by a method such as screwing. It is characterized by having done.

Further, from the rear end of the small diameter tube to a position slightly ahead of the position where the rear end of the discharge electrode is located, the outer surface of the front end portion of the rear electrode closely attached to the outer surface of the small diameter tube. It is characterized in that the external insulation provided in close contact with and the insulating wall portion of the small diameter tube are integrally molded with the same polymer compound.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, in a lightning arrester that obtains breaking performance by discharging inside a small-diameter tube, a discharge resistance increases when a surge current flows. The relation between the cross-sectional area S (mm2) and the length L (mm) of the small-diameter tube 1 functioning as an arc extinguishing chamber is selected as L> 80 × S raised to the power of 0.2.

In FIG. 1, reference numeral 2 is an insulating wall portion of a small diameter tube 1 made of a polymer compound having an insulating property such as ethylene vinyl acetate (hereinafter abbreviated as EVA), and 3 is a small diameter. The rear electrode is closely attached to the outer surface of the small-diameter tube 1 from the rear end of the tube 1 to a position slightly forward of the position where the rear end P of the discharge electrode 4 is located.
It is an external insulation provided in close contact with the outer surface of the tip of the. Figure 1
(A) has illustrated the case where the umbrella b is provided in the external insulation 5, and the creepage distance of the umbrella b part is lengthened.

Since the end portion of the back electrode 3 closer to the discharge electrode 4 has a high electric field when a surge lightning voltage is generated, an insulation structure having an interface easily causes dielectric breakdown. The insulation 5 and the insulation wall portion 2 of the small-diameter tube 1 are integrally molded with the same polymer compound having an insulation property such as EVA, and the interface between the outer insulation 5 and the insulation wall portion 2 is eliminated to obtain insulation performance. We are working to improve manufacturing costs and reduce manufacturing costs.

As shown in FIG. 2, the inner wall portion a of the small diameter tube 1 is made of a reinforcing material such as FRP, and the small diameter tube 1
The discharge electrode 4 is fixed to the inner wall portion a formed of a reinforcing material such as FRP at the tip of the discharge electrode 4 by a method such as screwing.

When the inner wall a is reinforced with a reinforcing material such as FRP, a short-circuit current flows inside the small diameter tube 1 and even if the internal pressure rises, the small diameter tube 1 functioning as an arc extinguishing chamber is prevented from being destroyed. Inner wall part a that is made of reinforcing material such as FRP
Since the screw threads can be formed on the tube 1, there is an advantage that the discharge electrode 4 or the back electrode 3 and the small-diameter tube 1 can be fixed with a simple screw structure.

In FIG. 2, an insulating wall portion 2 made of a polymer compound having an insulating property such as EVA is arranged outside the inner wall portion a made of a reinforcing material such as FRP. Insulating performance of the inner wall portion a is reinforced in the radial direction. However, when the insulating performance can be secured only by a reinforcing material such as FRP, the insulating reinforcement by the insulating wall portion 2 made of a polymer compound having insulating performance is performed. It is unnecessary. As the reinforcing material, in addition to FRP, for example, engineering plastic, vulcanized fiber, vinyl chloride, high density polyethylene, etc. can be applied.

In the continuous-current lightning arrester having the structure shown in FIG. 1, a radial compressive force is applied to the insulating wall portion 2 of the small-diameter tube 1 due to an increase in internal pressure due to a lightning surge current, and mechanical Although a polymer compound having low strength, such as silicone rubber, cannot be used, as shown in FIG. 2, when the inner wall portion a made of a reinforcing material such as FRP having high mechanical strength is provided,
The insulating wall portion 2 provided thereon has an advantage that a high molecular compound such as silicone rubber having low mechanical strength can be used.

Next, the relationship between the cross-sectional area S (mm2) of the small-diameter tube 1 capable of obtaining the instantaneous cutoff performance and the length L (mm) of the small-diameter tube 1 functioning as an arc extinguishing chamber is expressed as 0. The reason for selecting the power of 2 will be described with reference to the experimental results.

FIG. 3 is a schematic diagram of a three-phase AC voltage / lightning impulse voltage superposition experiment circuit used in the study. 6 is a short-circuit generator, 7 is an impulse voltage generator, 8 is a pin insulator, and A is
It is a prototype sample of the continuous current lightning arrester illustrated in FIG. 1 or 2.

The instantaneous cutoff performance depends on the relationship between the cross-sectional area S (mm2) of the small-diameter tube 1 of the prototype sample and the length L (mm) of the small-diameter tube 1 functioning as an arc extinguishing chamber and the passing lightning impulse current. However, the relationship between the cross-sectional area S (mm2) of the small diameter tube 1 that instantaneously cuts off in all the tested current regions and the length L (mm) of the small diameter tube 1 that functions as an arc extinguishing chamber is shown in FIG. Came to show. From FIG. 4, an approximate expression showing the relationship between the cross-sectional area S (mm2) of the small-diameter tube 1 and the length L (mm) of the small-diameter tube 1 functioning as an arc extinguishing chamber, which is necessary to obtain the instantaneous arc extinguishing performance, , L = 17
It was found to be 0xS to the power of 0.2.

In addition, among the experimental results, the
The plot of the data is as shown in FIG. In FIG. 5, for example, the --L calculated value coefficient 80 is the L
= 170 × S to the power of 0.2, the coefficient 170 is set to 8
Substituting 0, calculate L corresponding to each S, and
-Illustrated by a line. same as below.

Further, among the experimental results, the data which has been shifted to the half-wave short circuit and cut off is plotted, as shown in FIG. As a result, the relationship between the cross-sectional area S (mm2) of the small-diameter tube 1 and the length L (mm) of the small-diameter tube 1 functioning as an arc extinguishing chamber is 170xS 0.2 power>L> 80xS 0.2. It has been found that the instantaneous breaking performance can be obtained by the passing current of the continuous current lightning arrester A in the range of the power.

Therefore, when designing an instantaneous interruption lightning arrester, if it is desired to have an instantaneous interruption performance in a wide current range, an appropriate L and S within the range of L> 170 × S 0.2.
, Or to give the lightning arrestor strength,
By setting conditions such as the passing current of the lightning arrester,
L> 80xS when half-wave extinguishing can be allowed under certain conditions while maintaining a certain momentary interruption performance.
It was found that appropriate L and S should be obtained within the range of the power of 0.2. The cross-sectional area S of the small-diameter tube 1 obtained here
(Mm2) and the length L (m of the thin tube functioning as an arc extinguishing chamber
The relational expression of m) is very effective data in the design of the instantaneous interruption lightning arrester.

A usage example in which the continuous current lightning arrester A according to the present application is attached to the insulator 8 is shown in FIG. In FIG. 7, 9 is an upper metal fitting, 10 is a lower metal fitting, 11 is a distribution line, 12 is an upper electrode, and 13 is an external gap. An external gap 13 is provided between the continuous current lightning arrester A and the upper electrode 12.
Is used, the electric field at the tip of the discharge electrode 4 inserted in the small diameter tube 1 can be relaxed against a constant commercial frequency voltage. Therefore, generation of corona noise and continuous lightning protection in long-term use are prevented. This is effective in preventing deterioration of the device A.

[0027]

Since the present invention is constructed as described above, it has the following effects. It is possible to effectively provide a lightning protection device having an instantaneous blocking performance. Since the inner wall of the small-diameter pipe is reinforced with a reinforcing material such as FRP having high mechanical strength, it is possible to prevent the lightning arrester from being destroyed due to the rise in the internal pressure of the lightning arrester arc extinguishing chamber. Since the insulating wall of the small-diameter tube and the external insulation are integrally molded with the same polymer compound, the interface between the external insulation and the insulating wall is eliminated, the insulating performance is improved, and the manufacturing cost can be reduced. It is possible to effectively design a low-cost lightning protection device that has instantaneous cutoff performance.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the invention.

FIG. 2 is a sectional view showing another embodiment of the invention.

FIG. 3 is a schematic diagram of a three-phase AC voltage / lightning impulse voltage superposition experiment circuit.

FIG. 4 is a drawing showing the relationship between the cross-sectional area S of the small diameter tube that instantaneously cuts off in all current regions and the length L of the small diameter tube that functions as an arc extinguishing chamber.

FIG. 5 is a drawing showing the relationship between the cross-sectional area S of a small-diameter pipe in which the data of instantaneous interruption is plotted and the length L of the small-diameter pipe functioning as an arc extinguishing chamber.

FIG. 6 is a drawing showing the relationship between the cross-sectional area S of the small diameter tube in which the data that has shifted to a half-wave short circuit and cut off is plotted, and the length L of the small diameter tube that functions as an arc extinguishing chamber.

FIG. 7 is an explanatory diagram showing an example of use of a continuous current lightning arrester.

[Explanation of symbols] 1 small diameter tube 2 Insulation wall of small diameter pipe 3 Back electrode 4 discharge electrodes 5 External insulation 6 short-circuit generator 7 impulse voltage generator 8 insulators 9 Insulator top metal fittings 10 Lower insulator metal fittings 11 distribution line 12 Upper electrode 13 external gap A Continuous lightning arrester L Length of small-diameter pipe that functions as an arc extinguishing chamber Rear end of P discharge electrode Cross-sectional area of small diameter tube a Inner wall made of reinforcing material such as FRP b umbrella

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Maki Sakie 2-47 Shiobara, Minami-ku, Fukuoka-shi, Fukuoka Prefecture Kyushu Electric Power Co., Inc. Research Institute (72) Inventor Shuichi Maki Oita-shi, Oita Hara 2899 West Nippon Electric Cable Co., Ltd. (72) Inventor Kiyonori Watanabe Oita City, Oita Pref. 2899 Dahara Nishi Nihon Electric Cable Co., Ltd. (56) Reference JP-A-8-321372 (JP, A) JP 2001 -102149 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01T 4/14 H01T 1/08

Claims (3)

(57) [Claims] 1. A lightning arrester which obtains a breaking performance by an internal discharge of a small diameter tube. A cross-sectional area S (mm2) of the small diameter tube which can obtain an instantaneous breaking performance and a length L of the thin diameter tube which functions as an arc extinguishing chamber.
(Mm) relationship of L> 80 × S raised to the power of 0.2 2. An inner wall portion of the small diameter tube is formed of a reinforcing material such as FRP, and a discharge electrode is screwed to the inner wall portion of the tip portion of the small diameter tube formed of the reinforcing material. A continuous current lightning arrester according to claim 1. 3. The outer surface of the front end portion of the rear electrode, which is closely attached to the outer surface of the thin tube from the rear end of the thin tube to a position slightly forward of the position where the rear end of the discharge electrode is located. 2. A continuous current lightning arrester according to claim 1, wherein the external insulation provided in close contact with and the insulating wall portion of the small diameter tube are integrally molded with the same polymer compound.