JPH06283246A - Semiconductor-type lightning arrestor - Google Patents

Abstract

PURPOSE:To provide a semiconductor type lightning arrestor which is set in a hanging insulator and can deal with lightning with large energy as compared with a conventional one while the deformation of the original shape of the hanging insulator being suppressed to the minimum. CONSTITUTION:A semiconductor element 6 like a thyristor which becomes conductive at the time of over voltage is buried in a storage part 4 formed in a shade part 2 of a handing insulator 1. Consequently, since an arrestor can deal with lightening with large energy as compared with a conventional one made of a zinc oxide element, the number of the element sheets to be buried can be decreased and thus the deformation of the original shape of the hanging insulator is suppressed to the minimum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor lightning arrester incorporated in a suspension insulator.

[0002]

2. Description of the Related Art Non-linear resistance elements such as zinc oxide elements have been widely used in lightning arresters for electric power systems. This is an element that acts as an insulator for normal system voltage, but acts as a conductor for high voltage such as lightning surge voltage. Can be prevented.

The zinc oxide element is generally installed in parallel with the insulator series, but there is also an example in which the zinc oxide element 3 is embedded in the cap portion 2 of the suspension insulator 1 as shown in FIG. In this case, replace the existing suspension insulator string with this suspension insulator 1
There is an advantage that a lightning protection function can be provided simply by replacing

However, the lightning arrester incorporated in this type of suspension insulator has the following problems. First, since the zinc oxide element 3 has a low energy resistance, it cannot handle high-energy lightning such as winter lightning, and the element may be destroyed. Secondly, in order to prevent the influence of the element from breaking down to the main body of the suspension insulator 1 when the element is broken, the accommodating portion 4 of the zinc oxide element 3 has an opening such as a metal cap 5 which opens at a predetermined pressure. A pressure mechanism is required and the structure becomes complicated. Thirdly, since the zinc oxide element 3 has a low withstand voltage property per unit height, a large number of zinc oxide elements 3 must be provided in series, and the accommodating portion 4 of the zinc oxide element 3 has a cap portion of the suspension insulator 1 as shown in FIG. It greatly protrudes from 2. For this reason, the original shape of the insulator is destroyed. Fourth,
Since the zinc oxide element 3 has a high limit voltage when passing a lightning surge current, there is a limit to the number of elements that can be accommodated in one suspension insulator 1. That is, if the sum of the limiting voltages exceeds the withstand voltage characteristic of the suspension insulator 1 itself, a flashover occurs on the outer surface of the suspension insulator 1 when the lightning surge current passes. For this reason,
It is necessary to disperse and house the zinc oxide elements 3 in a large number of suspension insulators 1.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, is capable of treating large-energy lightning, has a simple structure, and is less likely to lose its original shape. The present invention has been completed to provide a semiconductor type lightning arrester incorporated in a suspension insulator that can accommodate a large number of elements in each suspension insulator.

[0006]

The present invention, which has been made to solve the above-mentioned problems, is characterized in that a semiconductor element which becomes conductive when an overvoltage occurs is embedded in a cap portion of a suspension insulator. .

[0007]

The present invention will be described below in more detail with reference to the illustrated embodiments. In FIG. 1, 1 is a suspension insulator, 2 is a cap portion thereof, and 6 is a semiconductor element embedded at a symmetrical position of the cap portion 2. As the semiconductor element 6, a thyristor element sandwiched between electrode plates 7 is used. These semiconductor element 6 and electrode plate 7 are embedded in a cylindrical housing portion 4 formed in the cap portion 2, and the top and bottom thereof are sealed by porcelain caps 8, 8. The lead wires 9 and 10 extending through the porcelain caps 8 and 8 are connected to the cap fitting 11 and the pin 12 of the suspension insulator 1, respectively.

The semiconductor element 6 is turned on by self-ignition when a lightning surge voltage due to a lightning strike is received, and has a function of passing a lightning surge current and blocking a follow-up current. In general, since the semiconductor element 6 has a predetermined direction in which a current can pass, as shown in FIG. 1, the semiconductor elements 6 are embedded at symmetrical positions of the cap portion 2 to cope with positive and negative lightning surges. Bidirectional semiconductor device 6
If it is used, it need only be embedded on one side.

One of the three electrode plates 7 shown in FIG. 1 is a spring electrode having a spring 13 inside as shown in FIG.
It is preferable that the semiconductor element 6 is in a pressure-bonded state by setting 7a. In this case, the upper and lower porcelain caps 8, 8 receive the spring force. Also, FIG.
If a disc spring 14 is interposed between the semiconductor elements 6 and 6 and the whole is integrated with the insulating bolts 15 as shown in FIG. 2, the cap portion 2 is embedded with a spring force. There is nothing to do.

[0010]

The thus constructed device is used as a suspension insulator string by connecting in series like a normal suspension insulator, and since the semiconductor element 6 is normally off, it is normally insulated. Demonstrate the function as an insulator. However, when a lightning surge voltage is received, the semiconductor element 6 is self-ignited and turned on, and the cap metal fitting 11 and the pin 12 are short-circuited to allow a lightning surge current to pass therethrough, thereby preventing a flashover accident. The lightning protection function described above is the same as that using a conventional zinc oxide element, but the semiconductor lightning protection device of the present invention is different from the conventional one in the following points.

First, a semiconductor device 6 such as a thyristor.
Since the energy resistance is much higher than that of the zinc oxide element, it is possible to easily handle high-energy lightning such as winter lightning, and there is no risk of the element being destroyed.
Therefore, the conventional pressure release mechanism that assumes the explosion of the element is not necessary, and the structure is simplified.

Second, a semiconductor device 6 such as a thyristor.
Has a larger withstand voltage characteristic per unit height than the zinc oxide element 3. Therefore, if the withstand voltage characteristics are the same,
The height of the element storage portion 4 can be made lower than in the conventional case, and the amount of vertical projection of the cap portion 2 can be reduced. As a result, the collapse of the original shape of the suspension insulator can be made smaller than that of the conventional product.

Thirdly, since the semiconductor element 6 has a low limit voltage when a lightning surge current passes, a large number of semiconductor elements 6 can be housed in one suspension insulator 1. (That is, even if a large number of semiconductor elements 6 are housed, the sum of their limiting voltages does not exceed the withstand voltage characteristics of the suspension insulator 1 itself, and a flashover may occur on the outer surface of the suspension insulator 1 when a surge current passes. Therefore, there is no need to disperse the lightning arrester elements in each suspension insulator as in the conventional case, and the system can be protected by simply connecting a small number of suspension insulators 1 of the present invention in a normal suspension insulator string. You can also do it.

[0014]

As described above, since the semiconductor type lightning arrester of the present invention has the semiconductor element embedded in the cap portion of the suspension insulator which becomes conductive when an overvoltage is generated, it is larger than the conventional product. It has many excellent effects such as being able to handle lightning of energy, simplifying the structure, suppressing the collapse of the original shape of the insulator, and being able to store many elements in one suspension insulator. It is a thing.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a conventional example.

FIG. 3 is a cross-sectional view showing a spring electrode.

FIG. 4 is a sectional view showing a semiconductor element integrated with an insulating bolt.

[Explanation of symbols]

 1 Suspension insulator 2 Cap part 4 Storage part 6 Semiconductor element 7a Spring electrode 15 Insulation bolt

Claims (3)

[Claims] 1. A semiconductor-type lightning arrester characterized in that a semiconductor element which becomes conductive when an overvoltage is generated is embedded in a cap portion of a suspension insulator. 2. The semiconductor type lightning arrester according to claim 1, wherein the semiconductor element is embedded in a state of being pressed by a spring electrode. 3. The semiconductor element is embedded in a state of being integrated by an insulating bolt.
The semiconductor type lightning arrester described.