JPS6226713A - Arresting insulator for aerial transmission line - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a lightning arrester insulator for overhead power transmission lines, and more specifically, the present invention relates to a lightning arrester insulator device for overhead power transmission lines, and more specifically, a lightning arrester insulator that is provided with transmission line suspension insulators on both left and right sides, and a lightning arrester insulator provided between both suspension insulators. This invention relates to a lightning arrester device for overhead power transmission lines equipped with an insulator.

(Conventional technology) Generally, overhead power transmission lines are installed on steel towers to quickly discharge abnormally high voltage caused by lightning strikes to the ground using lightning protection insulators to prevent ground faults and improve system reliability. A lightning arrester device is used.

As this conventional example, as shown in FIG.
The electric wire 30 is connected to the lower end of the insulator chain 86 via a clamp 87.
, and the upper camp fitting 88 has a supporting fitting 8.
An arcing horn 91 is fixed to the lower end of the lightning arrester 90, and an arcing horn 93 is fixed to the camp fitting 92 at the lower end of the insulator chain 86. There was something that was opposite.

On the other hand, conventionally, as shown in FIG. 6, an insulator chain 86 is suspended from the tip of the steel tower 1, and a lightning arrester 94 is directly connected between the electric wire 30 supported at the lower end of the insulator chain 86 and the steel tower l. There was a system that was built diagonally and used air gap heat, a system similar to lightning arresters at power generation and substations.

(Problem to be Solved by the Invention) However, in the former conventional device shown in FIG. Therefore, it was difficult to maintain a stable shape during erection, and installation work was time-consuming.

In a lightning arrester device with such a configuration, if the lightning arrester element has a low discharge withstand capacity, a low level of pollution resistance, and the lightning arrester is relatively smaller and lighter than the suspended insulator, it may be installed directly to the suspended insulator. The influence of the single lightning arrester on the behavior of the entire insulator device was negligible. However, as the scope of application has expanded and lightning arrester insulators have become larger due to increased discharge withstand capacity, implementation of safety measures, and demands for improved antifouling properties, the drawbacks of this pole mounting method have become impossible to ignore.

In other words, there is insufficient clearance due to static balance when there is no wind, abnormal vibration due to lateral vibration in the direction of the track or perpendicular direction under strong winds, and inertia due to the dead weight of the lightning arrester and vibrations on the end fittings of the suspended insulator. These include insufficient strength due to bending loads, and an increase in width under the edge due to installing the lightning arrester in a nearly horizontal position in order to ensure the insulating strength and air gap length of the lightning arrester.

On the other hand, in the conventional device shown in Fig. 6, when there is no wind or vibration, the load shared by the lightning arrester is only its own weight, but when the wire vibrates due to strong winds or falling ice or snow, horizontal Most of the load is borne by the lightning arrester, and the lightning arrester is required to have the same strength and reliability as a suspended insulator.1. Therefore, there was a problem that the size and weight increased significantly.

The tower arms also needed to have a special structure to withstand this load. Furthermore, since the wire is supported at two points, the suspension insulator and the lightning arrester, and the vertical load is shared and the horizontal load is borne, special lamps are required, resulting in a complex structure that reduces reliability and price. There was a problem with the surface.

Structure of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention rotatably connects an upper connecting yoke to a steel tower via a hanging metal fitting, and also The upper ends of a pair of left and right hanging insulators are rotatably connected and suspended parallel to each other, and a lower connecting yoke is rotatably connected between the lower ends of both the hanging insulators. , a power transmission line is supported at the lower central part of the lower connecting yoke, and at least one of the upper and lower parts of a lightning arrester is attached to the central part of the upper connecting yoke or the lower connecting yoke. The upper and lower connecting yokes, both suspension insulators, and lightning arrester insulators are arranged symmetrically with respect to a perpendicular line passing through the center of rotation of the upper connecting yoke, without being immovable in the left-right direction.

(Function) The present invention installs a lightning arrester between a pair of left and right suspension insulators,
In addition, the entire lightning arrester device is made symmetrical with respect to the perpendicular line passing through the center of rotation of the upper connecting yoke, making the entire device more stable and compact, making it easier to install the lightning arrester without considering the insulation gap with the steel tower. It will be held in Furthermore, even in an abnormal situation where either one of the two suspended suspension insulators is separated, this disconnected suspension insulator may have an air discharge gap between the lightning arrester and the power transmission line. The separated suspension insulator collides with the lightning arrester, but since the tower side yoke and the lightning arrester move as one, the detached suspension insulator does not collide with the normal suspension insulator, and therefore This prevents normal hanging insulators from breaking off and preventing power transmission lines from falling to the ground.

Furthermore, since the yoke and the lightning arrester move as one, and the mass of the lightning arrester acts to reduce the rotational speed of the yoke, the magnitude of the impact tensile load generated on the remaining suspension insulator is also the same as in the case without the lightning arrester. It has the advantage that it can be suppressed compared to In the case of a configuration in which both the upper and lower ends of the lightning arrester are connected to the connection yoke, even if one suspension insulator is separated, the lightning arrester and the remaining suspension insulator will suspend the electric wire, so the disconnected suspension insulator will The insulator does not collide with the lightning arrester, and damage to the lightning arrester is prevented. In this way, sufficient mechanical reliability can be ensured even in such an abnormal situation. Further, since only a tensile load is applied to the suspended insulator in the axial direction of the insulator by the work on the tower side and the energizing side yoke, it is easy to ensure mechanical strength and reliability can be improved.

(Example) Hereinafter, a first example embodying the present invention will be described based on FIGS. 1 to 3.

As shown in Fig. 1, a hanging bracket 2 with a roughly U-shape on the front is fixed to the steel tower 1 with bolts 3, and another hanging bracket 2 with a roughly U-shape on the side is fixed to the steel tower 1. A lower bracket 4 is hung so as to be rotatable in the left-right (track) direction and front-rear (orthogonal to the track direction) direction, and an upper connecting yoke 6 is connected in the left-right direction by a connecting pin 5 between the lower ends of the hanging bracket 4. It is suspended so that it can rotate.

Suspended insulators i!, which serve as a pair of left and right hanging insulators, are connected to both left and right ends of the upper connecting yoke 6 by connecting pins 7. 8. 8 are connected to be rotatable in the left-right direction, and connecting links 9.9 are connected to the lower ends of the suspension insulator chains 8, 8 so as to be rotatable in the left-right direction. Further, a lower connecting yoke 11 is connected between the lower ends of the connecting links 9.9 by a connecting pin 10 so as to be rotatable in the left and right direction. Furthermore, a connecting link 1 is provided by a connecting pin 12 at the lower center of the lower connecting yoke 11.
A clamp 14 is attached to the link 13, and a power transmission line 15 is attached to the clamp 14.
is supported, and the clamp 14 and the power transmission line 15 are fastened with a nut 16 so that they cannot move relative to each other.

As is clear from FIG. 1, the two suspended insulator chains 8.8 are suspended parallel to each other. The upper and lower connecting yokes 6.11 and the suspended insulator chains 8, 8 are symmetrical with respect to the perpendicular line H--H passing through the connecting pin 5, and are formed into a generally square shape as a whole.

Next, the lightning arrester 17 mounted on the upper connecting yoke 6 so as to be located between the two suspension insulator chains 8 will be described.

Near the center of the upper connecting yoke 6, a pair of left and right fixed mounting plates 18.18 are suspended and fixed by bolts 19, and between the lower ends of the refixed mounting plates 18.18 are hanging ears 25 provided on the lightning arrester 17. are tightened and fixed with bolts 20.

This lightning arrester 17 is located on the perpendicular line H-H passing through the connecting pin 5, and the M snow insulator 17 and both suspended insulator chains 8, 8 are constructed symmetrically with respect to the perpendicular line H-H.

Next, the structure of the lightning arrester 17 will be explained with reference to FIG. 2.3.

Cylindrical flange fittings 22 and 23 are fitted and fixed to the upper and lower outer circumferential surfaces of the porcelain insulator tube 21 by cementing 24. Hanging ears 25, 25 are integrally formed on the outer peripheral surface of the upper flange metal fitting 22 at 180 degrees from each other and are attached to the fixed mounting plate 18°18 by bolts 20.

On the end surfaces of the insulator pipe 21 and the flange fittings 22 and 23,
The terminal plates 26, 27 are fixed by a plurality of bolts 28 (eight in this embodiment, but only one is shown). Seal members 29 and 29 are interposed between the end faces of the insulator tube 21 and the terminal plates 26 and 27, respectively.

The terminal plates 26 and 27 are provided with pressure relief passages 26a and 27a that communicate the space inside the insulator tube 21 with the atmosphere.

The pressure relief passage 26 is provided on the end face of the terminal plate 26, 27.
A rupture disc 30.30 is brought into contact so as to cover 27a,
A pressure ring 31.31 is brought into contact with the surface of the rupture disc 30.30 and is fixed by the bolt 28. Seal members 32 and 33 are interposed concentrically at two locations between the end faces of the terminal plates 26 and 27 and the rupture discs 30 and 30, respectively, so that the space within the insulator tube 21 is maintained in a sealed state.

The pressing ring 31. is attached to the end surface of the terminal plate 26.27.
The opening edges of the pressure relief path forming covers 34.34 are brought into contact with each other so as to surround the outer periphery of the respective covers 34.31.
4 is fixed to the terminal plates 26 and 27 with a plurality of bolts 35. On the outside of the cover 34, there are pressure relief ports 34a, 34a that are inclined toward each other and correspond to each other.
is formed.

At the center of the lower surface of the lower pressure relief path forming cover 34, there is a ground-side discharge electrode that faces the energized-side discharge electrode 11a integrally formed in the upper center part of the lower connection yoke 11 with a certain air discharge gap G. An electrode 36 is provided to protrude downward.

On the other hand, on the outer circumferential surface of the flange metal fittings 22 and 23, a second.
As shown in Figure 3, the arcing ring arms '37a, 37
A is attached to the end thereof, and a substantially annular arcing ring 37.3 is attached to the end thereof so as to surround the insulator tube 21 with a margin.
7 is horizontally supported in a cantilever manner, and a portion thereof is cut out at a position corresponding to the pressure relief ports 34a, 34a, as shown in FIG.

Next, to explain the internal lightning protection structure of the insulator tube 21, the inside of the insulator tube 21 is made of reinforced plastic (F
A tension-resistant insulating cylinder 38 made of material such as RP) is accommodated,
Inner flange fittings 39 and 39 are fitted and fixed airtightly to the outer periphery of both upper and lower ends of the insulating cylinder 38 with an adhesive 40.

The end faces of both flange fittings 39.39 and the terminal plate 26.2
Attachment tubes 41 and 42 are interposed between them and 7, and are fixed with a plurality of bolts 43 and 44. Then, the upper mounting cylinder 41 is tightened and fixed to the terminal plate 26 by the bolt 43, and the tension-resistant insulating cylinder 38 is suspended and held in a predetermined position.

When the clamp 14 of the insulator device swings in a direction perpendicular to the track due to wire vibration caused by wind pressure, a difference occurs between the swing angles of the suspension insulator chain and the lightning arrester. Therefore, a relative displacement occurs between the discharge electrode 36 and lla, and the aerial discharge gap G is displaced. in this case,
It is preferable that the shape of the electrodes 36 be arcuate in the same direction to minimize changes in the shape. Furthermore, if the rated discharge current is large or if there is a problem with the strength, the discharge electrode 36 may be attached directly to the flange fitting 23.

On the other hand, pressure relief passages 39a, 39a are transparently provided in the lid of the flange fitting 39.39, and the flange fitting 39.39 and the mounting tube 41 are arranged so as to seal the passages 39a, 39a.
．． A rupture disc 45, 45 is interposed between the rupture disc 42 and the rupture disc 45.45. Seal members 46.degree. 46 are interposed between the flange fitting 39.degree. 39 and the rupture disk 45.45 and between the rupture disk 45.45 and the mounting tube 41.42, respectively. Further, a sealing member 47 is also interposed between the terminal plate 26 and the mounting tube 41.

An engagement recess 42a is formed in the lower end surface of the lower mounting tube 42, and an engagement protrusion 2 protruding from the upper surface of the terminal plate 27 is formed in the engagement recess 42a.
7b is inserted so as to be relatively movable in the vertical direction, and absorbs the relative movement in the vertical direction due to the difference in thermal expansion between the insulator tube 21 and the tension-resistant insulating tube 38, thereby preventing damage to the tension-resistant insulating tube 38. . Further, a seal member 48 is interposed between the engagement recess 42a and the engagement protrusion 27b. Further, a fall prevention bolt 49 is attached to the terminal plate 27 and attached to the mounting tube 42.
The insulator tube 21 is screwed to the flange fitting 39 through the insulator tube 21 to allow relative movement between the insulator tube 21 and the tension-resistant insulating tube 38.
This is to prevent the insulating tube 21 from falling when the insulating tube 21 is broken.

A recess 27c is formed on the upper surface of the terminal plate 27, and a spring 67 having a shunt 66 is housed in the recess 27c.
Its upper end is pressed against the lower end of the mounting tube 42 to establish electrical continuity.

A lightning arrester element 50 made of a material mainly composed of zinc oxide and having nonlinear voltage-current characteristics is accommodated in the tension-resistant insulating cylinder 38 . The lightning arrester element 50 has an annular tightening member 52.52 engaged with contact fittings 51.51 that are in contact with both upper and lower ends, and a tightening rod 53 formed of FRP is attached to this tightening member.
A plurality of pieces (iB) are inserted through the slot 54.

As shown in FIG. 3, an element 50 is pressed between the recess 39b of the flange fitting 39 and the contact fitting 5I to ensure good contact between the elements and to prevent mutual displacement of the elements due to external impact. Spring 6 with a centimeter 68 for preventing
9 is accommodated.

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

Now, when an abnormal voltage occurs on an overhead power transmission line due to an unexpected large-scale lightning strike, this current flows through the clamp 14 and the connecting link 1.
3. It is discharged to the discharge electrode 36 of the lightning arrester through the lower connection yoke 11 and the discharge electrode 11a on the power supply side. and,
After passing through the lightning arrester 17, the hanging ears 25 of the flange fitting 22, the fixed mounting plate 18, the upper connection yoke 6, and the hanging fitting 4
．． 2, it flows to the steel tower 1 and is grounded.

The abnormal voltage is detected by the lightning protection element 5 built into the lightning protection insulator 17.
In an electrically 4-conductor state where the current flows to 0 and the element 50 is destroyed, an extremely high temperature arc is generated by the following current. As a result, the pressure inside the tension-resistant insulation cylinder 38 increases, causing the rupture disc 45 to
．． 30 burst one after another, and the pressure relief passage 26 of the terminal plate 26, 27
A, the ultra-high temperature arc from 27a reaches the pressure relief path forming cover 34
．． 34, and is further discharged to the outside from the pressure relief ports 34a, 34a, and this arc moves to a pair of upper and lower arcing rings 37, 37.

Now, in the embodiment of the present invention, a pair of left and right suspension insulator chains 8.8 are rotatably suspended from the upper connecting yoke 6 which is rotatably suspended from the steel tower 1, and the suspension insulators 8.8 are The lower connecting yoke 11 is fixed between the lower ends of the series 888, and the upper end of the lightning arrester 17 is fixed to the center of the upper connecting yoke 6, and the rotation center of the upper connecting yoke 6, that is, the connecting pin 5 is fixed. Since each of the above-mentioned members is configured to be symmetrical with respect to the perpendicular line H-H, the stability when standing still is greatly improved, and there is no abnormal movement even when vibrating under strong winds. From this, the steel tower and M = b% child and! ! ! It is possible to install compact poles without having to consider extra insulation intervals between the insulators, and it is also possible to easily install the poles and stabilize the state of the pole installation.

In the event that either one of the pair of suspension insulators 8.8 is separated, the separated suspension insulator 8 is rotated around the connecting pin 7 toward the lightning arrester I7 and attached to the same lightning arrester 17. However, the severed suspension insulator chain 8 does not collide with the normal (suspension insulator chain 8), and therefore, the destruction of the normal suspension insulator chain 8 is reliably prevented and the power transmission line 15 is prevented from falling to the ground. It can be prevented.

By the way, when the suspension insulator series 8.8 and the lightning arrester 17 are installed parallel to each other as in the present invention, the suspension insulator series 8.
．． Due to the influence of the potential distribution of 8, the electric field acting on the lightning arrester 17 is harmonized, each lightning arrester element 50 shares the potential equally, the concentration of the electric field is eliminated, and the potentials shared by each element 50 are approximately equal. Therefore, the effect of shortening the lightning arrester 50 can be expected.

Next, a second embodiment of the present invention will be described based on FIG. 4.

This second embodiment is different from the first embodiment in that the lower end of the lightning arrester 17 is electrically connected to the lower connecting yoke 11 without providing an air discharge gap G. Incidentally, the only difference is the structure in which the lightning arrester 17 is attached to the connecting yoke 6.11, and the other configurations are the same as in the first embodiment.

Therefore, to explain only the different parts, a connecting link 56.56 is supported by a pin 55 near the center of the upper connecting yoke 6 so as to be rotatable in the left-right direction, and a lower end of the link 56.56 is supported by a pin 55 near the center of the upper connecting yoke 6. The upper ends of the hanging ears 57, 57 integrally formed on the flange fitting 22 to protrude upward are connected to the pins 58.
．． 58, they are connected so as to be rotatable in the front and rear directions.

On the other hand, connecting links 60, 60 and 61°61 are connected by pins 62 between the lower connecting yoke 11 and hanging ears 59, 59 provided on the lower flange fitting 23. Further, a lead wire 63 for noise prevention is connected between the lower connecting yoke 11 and the pressure relief path forming cover 34, and electrically connects the connecting yoke 11 and the lightning arrester 17. Note that one end of the lead wire 63 is connected to the pressure relief path forming cover 34 or a flange metal fitting, and the other end is fixed to the lower connecting yoke 11 with a metal fitting 64 and bolts 65.

In this second embodiment, the upper and lower connecting yokes 6.11 are connected to each other at the center by the lightning arrester 17.
Not only does the entire lightning arrester system become more stable, but when either one of the suspension insulator chains 8.8 is severed, the transmission line 1
5 can be supported by the lightning arrester 17, and as a result, there is no shock to the normal suspension insulator chain 8, and the power transmission line gripping function can be improved compared to the first embodiment. Other functions and effects are similar to those of the first embodiment.

Incidentally, in the first and second embodiments shown in FIGS. 1 and 4, the insulation strength of the suspension insulator chain 8 must be higher than this in order to allow the lightning arrester 17 to operate normally. Specifically, it is important to set the insulation gap Ll between the lightning arrester energized side arcing ring 37 and the tower side suspension insulator cap fitting to be 30% or more larger than the insulation gap L2 between the arcing rings 37°37. This is because the distance L2 between the arcing rings is generally set in coordination with the withstand voltage of the elements housed inside, so by making such coordination, even if a high voltage is applied, there will be no abnormality. It is possible to prevent failures in operation due to occurrence of faults.

In addition, in the one having the air gap shown in Fig. 1,
Insulation gap L3 between pressure relief path forming cover 34 and connection link 9
is 30% or more larger than the air gap G to ensure that discharge occurs
It is necessary to determine the electrode placement so that this occurs.

Furthermore, when it is desired to draw out and monitor the current flowing through the lightning arrester element for maintenance management, in the first embodiment, the mounting plate 18 and the upper connecting yoke 6 are insulated, and in the second embodiment, the connecting link 56 and the upper connecting yoke are insulated. There is a method of insulating the lightning arrester from the ground side by insulating it from the connecting yoke 6. It is preferable to attach the monitoring device to the side surface of the tower-side yoke 6 in order to easily cope with the deflection of the insulator device in the line direction or in the perpendicular direction.

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

(1) In the first embodiment, the lightning arrester 17 is mounted so as to be unrotatable in the left-right direction and rotatable in the front-rear direction.

At this time, the ground side discharge electrode 36 of the pressure relief path forming cover 34
It is desirable to form the side surface into an arcuate shape so that the air discharge gap G is always kept constant.

(2) Instead of the upper connecting yoke 6, the l lightning insulator 17 is supported upward on the lower connecting yoke 11 side. At this time, a discharge electrode 11a is provided on the upper connection yoke 6.

(3) For example, the rupture disc 45 or the pressure relief path forming cover 34
．． Any type of lightning arrester may be used, such as a type of lightning arrester in which 34 is omitted.

(4) In place of the suspension insulator chain 8.8, one or more long-stem insulators (path shown) may be used.

(5) In the embodiment shown in FIG. 4, for example, a plurality of pin insertion holes are provided in the vertical direction in the hanging ears 59 or the connecting links 60, 61, so that the length in the vertical direction can be adjusted. In this case, although a difference in length occurs between the suspension insulator chain 8 and the lightning arrester insulator 17 due to dimensional errors, this can be absorbed.

Effects of the Invention As detailed above, the present invention increases the stability of the entire lightning arrester device for overhead power transmission lines, thereby preventing the insulator device from causing abnormal vibrations and preventing excessive stress from being generated in the lightning arrester. Moreover, it is possible to reduce the size by removing unnecessary clearance. Furthermore, even if the suspension insulator should break, it is possible to prevent the normal suspension insulator from being destroyed, thereby improving mechanical reliability and facilitating the installation work.

[Brief explanation of the drawing]

1 is a front view of a lightning arrester device for power transmission lines installed on a pole, showing a first embodiment of the present invention; FIG. 2 is an enlarged half-sectional view taken along the line A-A in FIG. 1; and FIG. FIG. 4 is a front view showing the second embodiment of the present invention, and FIGS. 5 and 6 are front views showing the conventional example. 6...Upper connection yoke, 8...) U insulator chain, 11
... Lower connection yoke, 17 ... Lightning arrester, perpendicular H-
H0 patent applicant Tokyo Electric Power Company Nippon Insulators Co., Ltd.

Claims (1)

[Claims] 1. An upper connecting yoke is rotatably connected to the steel tower via a hanging metal fitting, and the upper ends of a pair of left and right suspension insulators are rotated to both ends of the upper connecting yoke. movable,
and are connected and suspended parallel to each other, and a lower connecting yoke is rotatably connected between the lower ends of both the suspension insulators, and
A power transmission line is supported in the lower central part of the lower connecting yoke, and at least one of the upper and lower parts of the lightning arrester is attached to the central part of the upper connecting yoke or the lower connecting yoke,
The lightning arrester is made immovable in the left-right direction, and the upper and lower connecting yokes, both suspension insulators, and lightning arrester are arranged symmetrically with respect to a perpendicular line passing through the center of rotation of the upper connecting yoke. Lightning arrester device for overhead power transmission lines. 2. The lightning arrester is cantilevered and fixed to the upper connecting yoke, and between the grounding side discharge electrode provided at the lower end of the lightning arrester and the energizing side discharge electrode provided on the lower connecting yoke, Claim 1 in which a predetermined air discharge gap is provided.
Lightning arrester device for overhead power transmission lines as described in . 3. The lightning arrester device for an overhead power transmission line according to claim 1, wherein the lightning arrester is connected to and electrically connected to upper and lower connecting yokes, respectively.