JPS63138611A - Arresting insulator - 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] Purpose of the Invention (Field of Industrial Application) This invention equalizes the surface leakage current of the insulator, eliminates areas where local potential concentration occurs, and makes the potential distribution uniform when viewed as a series of insulators. This invention relates to a suspended insulator-type lightning arrester that has become smaller in size.

(Prior art) Conventionally, in order to prevent ground faults on power transmission lines, suspension insulators with lightning arresters that absorb lightning surges have been constructed with non-linear resistance elements such as zinc oxide (ZnO) inserted through their caps. It has been proposed that they be buried and fixed at equal angles.

This suspension insulator has a structure in which upper and lower electrodes are provided at the upper and lower ends of a power wire resistance element, a metal lid is placed over the top, and the upper and lower electrodes are connected to the metal body using a lead wire. is taking.

(Problems to be Solved by the Invention) When a suspension insulator is used outdoors under dirty conditions, leakage current flows from the vicinity of the upper and lower electrodes at both the upper and lower ends of the lightning arrester to the outer periphery due to contamination on the surface of the insulator. However, since the lightning arrester element is not placed around the entire circumference of the insulator shade, only the area around the upper and lower electrodes dries up due to the heat generated by the leakage current, forming a dry belt, and the insulation in that area becomes high. Potential concentration occurs near the electrode. At this time, when viewed as a chain of insulators, the progress of forming the dry belt is easily influenced by the state of contamination, so that the voltage share is locally concentrated on a certain insulator. For this reason, there is a problem in that electrical flashing or discontinuity is likely to occur in the element. Furthermore, local discharge occurring in the dry belt section may cause interference with radio waves and the like.

Structure of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a method in which a cap metal fitting is capped and fixed to the head of the hill portion, and a bottle metal fitting is fitted and fixed inside the head. In a suspension insulator that connects a plurality of insulator bodies, a lightning arrester with non-linear voltage-current characteristics is buried near the center of the cap, and conductors are led out from both the upper and lower electrodes of the lightning arrester and connected upwardly. A ring-shaped electrode is connected to the lower electrode and the upper electrode of the side and lower side insulators directly or indirectly through a cap metal fitting or a bottle metal fitting, and is electrically connected to the upper electrode and the lower electrode, respectively, on the front or back side of the cap. A method is adopted in which the bottle is provided at the center of at least one of the areas.

(Example) An example embodying this invention will be described below with reference to FIGS. 1 and 2.
To explain according to the diagram, 1 in the diagram is a steel tower (not shown)
an arm provided on the arm 1, and a support fitting 2
A large number of suspended insulator-type lightning arresters 3 are connected and suspended in series, and a power transmission line is supported at the lowest end of the lightning arrester 3 via a hanging metal fitting 4.

As shown in FIG. 1, the insulator main body 5 constituting the lightning arrester 3 includes a hill portion 5a, an insulating fold 5b formed annularly and concentrically on the inner surface of the hill portion 5a, and further includes a hill portion 5a. It consists of a capped cylindrical head 5c integrally molded at the upper center of the head 5c. Further, a cap metal fitting 7 is fixed to the head 5c with cement 6, and an engagement recess 7a is formed in the upper part of the metal fitting 7 so as to be able to engage the bottle metal fitting 8 of the lightning arrester 3 directly above. It has become. The upper part of the bottle fitting 8 is fixed inside the head 5c with cement 6, and the lower end is engaged with the engagement recess 7a of the cap fitting 7 of the lightning arrester 3 directly below. In this way, a plurality of lightning arresters 3 are connected in series. Note that the mechanical load is borne by the head 5c, the cement 6, the cap fitting 7, and the bottle fitting 8. The configuration described above is the same as that of a conventional suspended insulator.

A plurality of cylindrical element housing portions 9 are integrally formed at equal angular intervals in the vertical direction at a position near the center of the cap portion 5a.

The element housing portion 9 accommodates a lightning arrester element 10 which is mainly made of zinc oxide (ZnO) and has non-linear voltage-current characteristics and is excellent in follow-on current blocking characteristics. Further, upper and lower electrodes 11 and 12 are hermetically fitted to both upper and lower ends of the element housing portion 9.

The upper electrode 11 is electrically connected to the cap metal fitting 7, and the lower electrode 12 is electrically connected to the bottle metal fitting 8 through lead wires 13 and 14 led out from positions near the center of the hill portion 5a of the element housing portion 9, respectively. .

Ring-shaped electrodes 15.16 as auxiliary electrodes are attached to portions of the front and back surfaces of the hill portion 5a close to the lightning arrester 10, and lead wires 13.14 are led out from the upper electrode 11 and the lower electrode 12. It is connected to the. The ring-shaped electrodes 15 and 16 are provided concentrically around the bottle fitting 8, and are made of metal such as tin or zinc, baked silver, or the like.

In addition, the lightning arrester 3 has a complete load-bearing part consisting of a head 5c, cement 6, cap fitting 7, bottle fitting 8, etc., a lightning arresting function part consisting of an element accommodating part 9, a lightning arresting element 10, and both upper electrodes 11 and 12. It is separated into

Next, the operation of the lightning arrester constructed as described above will be explained.

Send III! When an excessive voltage due to a lightning surge is applied to L, the current flows to the pin fitting 8 of the lightning arrester 3 via the hanging fitting 4,
Lead wire 14 → lower electrode 12 → lead wire 18 → lightning arrester element 10 → upper electrode 11 → lead wire 13 → cap metal fitting 7 →
It is grounded to the earth via the support fitting 2 and the arm 1.

At this time, the lightning arrester element 10 built into the insulator body 5 quickly reduces its resistance value due to its characteristics and discharges the large current caused by the lightning surge to the ground.

Further, in response to the follow-on current that continues to the lightning surge, since the line voltage is low, the lightning arrester element 10 immediately restores the resistance value and recovers the insulation, so the follow-on discharge is suppressed and cut off, and the electric line returns to normal. do.

In addition, since the leakage current that normally flows on the surface of the cap 5a flows between the ring-shaped electrodes 15 and 16 provided around the entire circumference, the current density is reduced and is not concentrated locally. Since the dry belt that is formed also progresses uniformly over the entire insulator chain, it is possible to prevent local potential concentration from occurring in a certain insulator. As a result, it is possible to shorten the element length and reduce the size of the insulator.

Further, both the upper and lower electrodes 1 are provided by ring-shaped electrodes 15 and 16.
1.12 Since there is no local discharge in the surrounding area, radio interference such as radio noise will not occur.

In addition, in the embodiment of the present invention, from the load-bearing part consisting of the head 5c, the cement 6, the cap metal fitting 7, and the pin metal fitting 8, to the element housing part 9, the lightning arrester element 10. Since the lightning arrester function section consisting of the upper and lower electrodes 11, 12, etc. is completely separated, separation of the insulator body 5 when the lightning arrester element 10 is abnormal can be prevented. In other words, the high mechanical reliability of the current suspension insulator can be maintained as is, the head design is reasonable, and the current design technology of the insulator can be used.

The present invention is not limited to the above-mentioned embodiments, but can also be embodied in the following other embodiments.

(1) As shown in FIG. 3, the element housing part 9 is molded into a cylindrical shape separately from the cap 5a using resin such as FRP, and the cap 5a is molded into a cylindrical shape.
It is also possible to embed it in the insertion hole 5d formed in the inside a and apply an adhesive 17 to the contact portion between the two to connect them. In this case, the shock to the cap part 5a when the lightning arrester element 10 is abnormal can be more relaxed than the element accommodating part 9 which is integrally molded with porcelain in the above embodiment. Alternatively, the element accommodating portion 9 may be separately formed in a cylindrical shape from porcelain and heat-fused to the cap portion 5a using glaze.

(2) Although three lightning arresting elements 10 were provided in the above embodiment, any number of lightning arresting elements 10 such as 1.2 or 4 or more may be used. For balance, it is better to have more than one.

(3) In the above embodiment, the upper electrode 11 and the cap fitting 7,
Connect the lower electrode 12 and the pin fitting 8 to each other and connect the single lead wire 13.1.
4, the upper electrode 11 and lower electrode 12 of the vertically adjacent lightning arrester 3.3 may be directly connected by a lead wire. In this case, it is desirable to provide terminal portions on both the upper and lower electrodes 11 and 12 so that lead wires can be easily connected.

(4) In the above embodiment, the element accommodating portions 9 are provided facing each other in the same phase through a gap, but as shown in FIG. The parts 9 may be arranged alternately.

(5) The element housing portion 9 is not only cylindrical, but also rectangular and cylindrical.
It can also be shaped into an elliptical cylinder, a curved rectangular cylinder as shown in FIG. 5, or the like.

Effects of the Invention The present invention can prevent local discharge due to local concentration of potential that occurs around the electrodes of the lightning arrester in a suspended insulator type lightning arrester, and can also average out the shared voltage applied to each insulator, making it possible to Compared to an insulator-type lightning arrester, the size of the insulator body can be made smaller, which is advantageous from the standpoint of lightning arrester design.

[Brief explanation of the drawing]

Fig. 1 is a half-assembled cross-sectional view of a lightning arrester showing an embodiment of the present invention, Fig. 2 is a front view of a road body showing the usage state of the lightning arrester, and the third factor is a partial longitudinal section showing another example of the invention. Front view, 4th
The figure is an upside-down T: A plan view showing another example of the arrangement of the element accommodating part of the insulator, and FIG. 5 is a plan view showing another example of the element accommodating part. 5a...8 parts, 5c...head, 7...cap metal fitting, 8...pin metal fitting, 9...element accommodating part, 10...
・Lightning protection element, 11 (12)...upper (lower)! pole, 1
3.14...Lead wire, 15.16...Ring-shaped electrode.

Claims (1)

[Claims] 1. A cap metal fitting (7) on the head (5c) of the cap (5a)
The head (5c) is fixed with a pin fitting (8) inside the head (5c).
In a suspension insulator that connects a plurality of insulator bodies formed by inserting and fixing, a lightning arrester element (10) with non-linear voltage-current characteristics is buried near the center of the cap (5a), and the same lightning arrester element (10) Conductors are led out from both the upper and lower electrodes (11) and (12) of the lower electrodes (11 and 12) of the upper and lower insulators, respectively.
12) and the upper electrode (11) directly or indirectly through the cap metal fitting (7) and the pin metal fitting (8),
The ring-shaped electrodes (15) and (16) which are electrically connected to the upper electrode (11) and the lower electrode (12), respectively, are connected to the cap (5a).
A lightning arrester characterized in that a pin is centrally provided on at least one of the front surface or the back surface. 2. The lead wire (13) is connected between the upper electrode (11) and the cap fitting (7) and between the lower electrode (12) and the pin fitting (8).
The lightning arrester according to claim 1, which is connected between.