JPH0326888B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a lightning arrester device for an overhead power transmission line. More specifically, the present invention relates to a lightning arrester device for an overhead power transmission line that has an insulation recovery function and can retransmit power even if a zinc oxide element built into the lightning arrester fails.

[Conventional technology]

Conventionally, the zinc oxide element built into the lightning insulator of the lightning insulator installed between the steel tower and the overhead power transmission line, which has non-linear voltage-current characteristics, has deteriorated and is struck by lightning, or the zinc oxide element becomes normal. However, if the element is damaged by a large-scale lightning strike, the zinc oxide element becomes conductive due to the follow-on current based on the operating voltage following the lightning surge. As a result, current flows from the overhead power transmission line to the tower via the lightning arrester device, causing a ground fault, which is then interrupted by a circuit breaker at the substation. However, even after the circuit breaker was activated, the insulation of the lightning arrester had not recovered.
Retransmission becomes impossible.

A lightning insulator device for overhead power transmission lines for preventing the occurrence of such abnormal conditions is disclosed in Japanese Patent Application Laid-Open No. 138202/1983. In this lightning arrester device for an overhead power transmission line, a power transmission line is suspended from a support arm of a suspension tower by a suspension insulator, and a lightning arrester is suspended from the support arm at a predetermined distance from the suspension insulator. A disconnection mechanism that is ruptured by a faulty ground fault current is provided at the lower part of the lightning arrester, and the lower end of the suspension insulator and the lightning arrester are connected via this disconnection mechanism. That is, the lightning arrester is arranged in a substantially V-shape so as to be inclined toward the suspension insulator with respect to the suspension insulator suspended from the support arm. When the zinc oxide element built into the lightning protection insulator is healthy, it quickly discharges against lightning surge current, and the resistance value is restored due to the nonlinear resistance characteristics of the zinc oxide element against follow-on current. Power can be retransmitted. Furthermore, when the zinc oxide element deteriorates or is damaged and faulty ground fault current flows, the disconnection function is activated to release the connection between the lower end of the suspension insulator and the lightning arrester, and remove the inclined lightning arrester. It is configured to rotate vertically around its upper hanging point due to gravity. Thereby, a predetermined insulation clearance is secured between the overhead power transmission line and the lightning arrester, and power can be retransmitted.

[Problem to be solved by the invention]

However, with this conventional lightning arrester system, for example, for 500KV, the suspended lightning arrester weighs about 1 ton, so in order to withstand the shock and vibration when disconnected, the tower side must be reinforced. There was a problem with the strength.

In addition, since the lightning arrester after being separated is suspended from the support arm with its lower end free, the lightning arrester may sway significantly due to strong winds, etc. In this case, the required insulation between the power transmission line and the lightning arrester may be affected. There was a problem with not being able to secure clearance.

In other words, in order to install this lightning arrester device on an existing steel tower, it is necessary to change the specifications of the tower, such as reinforcing the tower or lengthening the support arm to ensure insulation clearance. It was difficult to apply lightning arrester devices to steel towers.

The first object of the present invention is to make it possible to retransmit power even if the zinc oxide element built into the lightning arrester breaks down, to easily transfer power to existing towers, and to reduce the unbalanced tension newly acting on the tower as much as possible. An object of the present invention is to provide a lightning arrester device for an overhead power transmission line that can be made smaller.

In addition to the first object, the second object of the present invention is to prevent the lightning surge current from entering the hanging insulator device of the overhead power transmission line even if the lightning surge current enters from either the front or back direction of the overhead power transmission line. An object of the present invention is to provide a lightning arrester device for an overhead power transmission line that can prevent the flow of lightning.

[Means to solve the problem]

In order to solve the above-mentioned problems, a first invention connects in series an insulating support insulator and a lightning arrester incorporating a zinc oxide element with non-linear voltage-current characteristics, and connects both ends of the support insulator in series. In between, install a conductor that does not operate due to lightning surge current and disconnects due to follow-on current.
The supporting insulator and lightning arrester connected in series are installed between the steel tower and a position spaced apart from the tower when viewed from the plane of the overhead power transmission line via a connecting fitting, and the supporting insulator and lightning arrester are connected in series with each other, and the supporting insulator and the lightning arrester are connected in series. A tension insulator for strength balancing is installed on the opposite side of the installation position of the lightning arrester insulator and located between the overhead power transmission line and the steel tower.

Further, the second invention provides a support insulator provided with a conductor and a lightning arrester insulator for strength balancing in place of the tension insulator for strength balancing of the first invention.

[Effect]

In the first invention, when a lightning surge current flows through the power transmission line, it is discharged from the steel tower to the ground through the conductor attached to both ends of the insulating support insulator and the zinc oxide element built into the lightning arrester. At this time, the lightning surge current is discharged due to the nonlinear resistance characteristics of the zinc oxide element, and the resistance value of the zinc oxide element is restored after discharge, so that follow-on current is suppressed and ground faults are prevented.

Further, when the zinc oxide element deteriorates or is damaged by an unexpected large-scale lightning strike, the zinc oxide element becomes conductive and a follow-on current flows. This follow-on flow causes the conductor attached to the support insulator to break off. For this reason,
After that, the necessary insulation clearance is secured by the support insulator, and power can be transmitted again.

On the other hand, even if the conductor is disconnected, the lightning arrester is not mechanically disconnected and remains supported overhead between the tower and the power transmission line. Therefore, there is no need to reinforce the steel tower.

In this first invention, since the insulating support insulator and the lightning arrester are connected in series, the length of the connection is longer than in the case of only the lightning arrester, but the support insulator and the lightning arrester are Since the steel tower is installed between the steel tower and the overhead power transmission line located at a distance from the steel tower via a connecting fitting, it can be installed on an existing steel tower without changing its specifications.

Further, in the first invention, since the tension insulator for strength balancing is installed on the opposite side to the support insulator and the lightning arrester insulator,
The unbalanced tension acting on the steel tower is eliminated.

On the other hand, the second invention, in addition to the effect of the first invention, prevents the lightning surge current from flowing into the hanging insulator device of the overhead power transmission line even if the lightning surge current enters from either the front or back direction of the overhead power transmission line. This can be reliably prevented.

〔Example〕

Hereinafter, an embodiment embodying the first invention will be described based on FIGS. 1 to 4. In the drawings, 1 is a steel tower, 2 is a tension insulator device installed on a support arm 3 of the steel tower, and 4 is a tension insulator device installed on a support arm 3 of the steel tower. The overhead power transmission line 5, which is hung on the tension insulator device 2, is a jumper wire. Reference numeral 6 denotes a lightning arrester unit installed between the steel tower 1 and the overhead power transmission line 4.

To explain the configuration of the lightning arrester unit 6 with reference to FIG. 4, an insulator 9 is connected to the steel tower 1 via a connecting fitting 8, and the insulator 9 has an insulation function in the event of an abnormality via a mounting fitting 10. One end of a suspension insulator chain 11 serving as a support insulator is connected.
Further, a lightning arrester 13 is connected in series to the other end of the suspension insulator chain 11 via a mounting bracket 12. This lightning arrester 13 includes a cylindrical insulator 14 and a cylindrical insulator 14.
4, a zinc oxide element 15 having a lightning arresting function, an end fitting 16 fitted and fixed to both ends of the insulator tube 14, and a connecting fitting for connecting the zinc oxide element 15 and the end fitting 16. 17.

Further, a lightning arrester 13' similar to the lightning arrester 13 is connected to the lightning arrester 13 via a connecting fitting 18, and a mounting fitting 19 as a connecting member and the connecting wire 7 are connected to the lightning arrester 13'. has been done.

On the other hand, the mounting brackets 10 and 12 include a rupture mechanism 20 that does not operate due to lightning surge current but responds to follow-on current.
21 is attached, and a bypass conductor 22 is installed in parallel between the upper ends of both the breaking mechanisms 20 and 21. The breaking mechanisms 20 and 21 are configured, for example, by using the trailing current as a trigger to ignite gunpowder, explode and destroy the container of the breaking mechanism, and scatter the side conductor 22. Breaking mechanism 20, 21 for fusible wire that responds to follow-on current and melts
There is also a configuration in which the bypass conductor 22 is replaced.

Arching horns 23 and 24 are attached to the mounting fittings 10 and 12, and the breaking mechanisms 20 and 21
When the suspension insulator chain 11 is operated and both ends of the suspension insulator chain 11 are connected by an arc, it is immediately moved away from the suspension insulator chain 11 to prevent its damage. Arcing horns 25, 26,
25' and 26' are installed, and lightning arresters 13 and 1 are installed.
If the surface of the lightning arrester 3' is abnormally contaminated or flashed due to a large-scale lightning strike, the generated arc is immediately moved away from the lightning arrester to prevent its damage.

Shield rings 27 and 28 are attached to the mounting fitting 12 and the end fitting 16 to alleviate the electric field between the right end of the suspension insulator chain 11 and the ground side of the lightning arrester 13. Further, a shield ring 29 is attached to the cap fitting 16' of the lightning arrester 13'.
The electric field on the charging side of the lightning arrester 13' is relaxed to smooth the voltage distribution of the zinc oxide element 15'.

In this embodiment, for convenience of explanation, the suspension insulator chain 11, lightning arrester insulators 13, 13', connecting line 7, etc. are collectively referred to as a lightning arrester unit 6.

Next, the construction work of the lightning arrester unit 6 constructed as described above will be explained.

First, as shown in FIGS. 2 and 3, at a predetermined position of the steel tower 1, that is, corner A of the four corners A to D, the tension insulator device 2 is suspended from the support arm 3 at a point P.
A connecting fitting 8 is attached to a position P2 higher than P1, and an insulator 9 is attached to the insulator fitting 8.

On the other hand, a retaining metal fitting 30 is attached to a predetermined position P3 of the overhead power transmission line 4 on the right side, and the connecting wire 7 is hooked to the metal fitting 30. At this time, the lightning arrester unit 6 is arranged so that it has a component in the same direction as the installation direction Y of the overhead power transmission line 4, as shown in FIG. 3, and in the horizontal direction X and vertical direction Z, as shown in FIGS. Build it so that it has a component.

Further, as shown in FIG. 3, a lightning arrester unit 6 is installed between the corner C of the tower 1 and the overhead power transmission line 4 on the left side in the same manner as described above.

On the other hand, between the corner B of the tower 1 and the overhead power transmission line 4 on the right side, there is a connection between the corner A of the tower 1 and the overhead power transmission line 4 on the right side.
A tension insulator 31 is installed to reduce the unbalanced tension exerted on the steel tower 1 by the lightning arrester unit 6 installed between the tower and the tower. This tension insulator 31 includes the lightning arrester 13, 13' of the lightning arrester unit 6 described above, and the breaking mechanism 2.
0, 21, bypass conductor 22 and shield ring 27
-29 etc. are omitted.

Additionally, between the corner D of the tower 1 and the overhead power transmission line 4 on the left side, there is an imbalance caused to the tower 1 by the lightning arrester unit 6 installed between the corner C of the tower 1 and the overhead power transmission line 4 on the left side. A tension insulator 31 is installed to reduce tension.

Next, the operation of the lightning arrester device for overhead power transmission lines constructed as described above will be explained.

Now, if a lightning surge current flows through the overhead power transmission line 4,
The attachment fitting 12 is connected from the hold-down fitting 30 attached to the overhead power transmission line 4 through the connecting wire 7 and through the zinc oxide elements 15, 15' built in the lightning arrester 13, 13'.
The electricity is discharged from the steel tower 1 to the ground via the breaking mechanism 21, the conductor 22, the breaking mechanism 20, and the mounting bracket 10. At this time, the lightning surge current is discharged due to the nonlinear resistance characteristics of the zinc oxide element, and after discharge, the resistance value of the zinc oxide element is restored and connection is suppressed. Therefore, the rupture mechanisms 20 and 21 do not operate, and the lightning surge current flows through the conductor 22.

In addition, abnormal discharge occurs due to deterioration of the zinc oxide elements 15, 15' in the lightning arrester 13, 13' or an unexpected large-scale electric shock, and the shunt conductor 22, which was electrically short-circuiting the suspension insulator chain 11, At the moment when the follow-on current flows, the breaking mechanisms 20 and 21 operate to cut off the side conductor 22 and replace the main body of ground insulation with the lightning arrester 13,
Move from 13' to suspension insulator 11. Pull-up insulator 1
1 are connected by an arc by the operation of the breaking mechanisms 20 and 21, but this arc immediately moves to the arcing horns 23 and 24. Since this condition is a ground fault phenomenon, the function of the substation senses this and the circuit breaker opens the line, thus extinguishing the arc and turning it back on after a certain period of time to continue power transmission. At this time, the breaking mechanisms 20 and 21 of the suspended insulator chain 11 operate to cut off the side conductor 22, so that insulation is restored and power can be transmitted again.

Now, in this embodiment of the first invention, since the lightning arrester unit 6 is installed between the overhead power transmission line 4 and the steel tower 1 at a position P3 displaced from the tower toward the track when viewed from the top, the lightning arrester unit 6 has a long insulator length. can be constructed without changing the specifications of the steel tower 1.

In addition, in the embodiment of the first invention, as shown in FIG. 3, in order to eliminate the unbalanced tension that occurs when only the lightning arrester unit 6 is installed, a tension insulator 31 is connected to the connecting wire 7 on the opposite side of the lightning arrester unit 6. Since the steel tower 1 is constructed using the above method, the tension acting on the steel tower 1 can be balanced, making reinforcement of the steel tower unnecessary and improving its durability.

Next, an embodiment embodying the second invention will be described with reference to FIG.

In this embodiment of the second invention, a lightning arrester unit 6 constructed similarly to the lightning arrester unit 6 described above is installed in place of the tension insulator 31 used in the embodiment of the first invention described above.

In the lightning arrester device of this embodiment, even if a lightning surge current enters from either the front or rear direction of the overhead power transmission line 4, the lightning arrester unit 6 is activated before the lightning surge current reaches the tension insulator device 2 side. Therefore, the voltage acting on the tension insulator device 2 can be maintained below a certain value, and therefore, the lightning surge current can be reliably handled by the lightning arrester unit 6, improving the operational reliability of the lightning arrester device. be able to.

Note that the present invention can also be embodied in the following embodiments.

(1) As shown in FIG. 6, as another example of the first invention, lightning arrester units 6 are installed for each of the single-line steel tower 1 and its three overhead power transmission lines 4, and
A tensile insulator 31 is attached to the connecting wire 7 between the central overhead power transmission line 4 and the steel tower 1 to alleviate the unbalanced tension exerted on the steel tower 1 by the lightning arrester unit 6 placed in the center.
shall be constructed by

(2) In each of the above embodiments, the present invention is embodied in a tension-resistant steel tower, but it may also be embodied in a suspended steel tower or a V-hanging steel tower. Furthermore, the attachment points of the lightning arrester unit 6 to the steel tower were set at the corners A to D of the steel tower 1;
Since there are various structures of the steel tower, the support arm 3 may be used as necessary.

[Effects of the Invention] As detailed above, the first invention allows power to be retransmitted even if the zinc oxide element built into the lightning arrester fails, can be easily installed on an existing tower, and can be installed on a new tower. This has the effect of suppressing unbalanced tension acting on the steel tower and improving durability.

Moreover, the second invention has, in addition to the effects of the first invention,
This has the effect of reliably preventing lightning surge current from flowing into the hanging insulator device of the overhead power transmission line, even if lightning surge current enters from either the front or back of the overhead power transmission line.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the lightning arrester device for overhead power transmission lines according to the first invention, Fig. 2 is a partially enlarged front view, Fig. 3 is an enlarged plan view, and Fig. 4 is an illustration of the lightning arrester unit. FIG. 5 is an enlarged front view, FIG. 5 is a plan view showing an embodiment of the lightning arrester device of the second invention, and FIG. 6 is a plan view showing another example of the first invention. 1... Steel tower, 2... Tensile insulator device, 3... Support arm, 4... Overhead transmission line, 6... Lightning arrester unit, 7... Connecting wire as connecting fitting, 11... Suspension as supporting insulator Insulator chain, 13, 13'...Lightning arrester, 15...Zinc oxide element, 19...Mounting metal fitting as a connecting metal fitting, 20, 21... Breaking mechanism,
22...Side conductor, 31...Tension resistant insulator, P3...
Position, Y...direction of overhead power transmission line, X...horizontal direction, Z...vertical direction.

Claims (1)

[Scope of Claims] 1. An insulating support insulator 11 and lightning arrester insulators 13, 13' incorporating a zinc oxide element 15 with non-linear voltage-current characteristics are connected in series, and the support insulator 1
A conductor 22 that does not operate due to lightning surge current and is separated by following current is attached between both ends of the support insulator 11 and lightning arrester insulators 13, 13' connected in series,
The steel tower 1 seen from the plane of the steel tower 1 and the overhead power transmission line 4
Connecting fittings 7, 19 are connected between the position P3 and the
and located between the overhead power transmission line 4 and the steel tower 1 on the opposite side of the steel tower 1 from the installation position of the support insulator 11 and the lightning arrester insulators 13, 13', Tension-resistant insulator 3 for strength balance
1. A lightning arrester device for an overhead power transmission line, characterized in that: 2 The connecting fittings include the mounting fitting 19 and the mounting fitting 19.
A lightning arrester device for an overhead power transmission line according to claim 1, which comprises a connecting wire 7 connected to a lightning insulator device for an overhead power transmission line. 3 An insulating support insulator 11 and lightning arrester insulators 13 and 13' containing a built-in zinc oxide element 15 with non-linear voltage-current characteristics are connected in series, and the support insulator 1
A conductor 22 that does not operate due to lightning surge current and is separated by following current is attached between both ends of the support insulator 11 and lightning arrester insulators 13, 13' connected in series,
The steel tower 1 seen from the plane of the steel tower 1 and the overhead power transmission line 4
Connecting fittings 7, 19 are connected between the position P3 and the
and located between the overhead power transmission line 4 and the steel tower 1 on the opposite side of the steel tower 1 from the installation position of the support insulator 11 and the lightning arrester insulators 13, 13', A lightning arrester device for an overhead power transmission line, characterized in that a support insulator 11 having a conductor 22 for strength balancing and lightning arrester insulators 13, 13' are installed.