JPS6059685B2 - insulator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an insulator that supports a conductor and can accurately measure the voltage applied to the insulator.

In conventional power distribution lines, the insulator that supports the conductor and the voltage detection device are separate, and the voltage detection device spoils the aesthetic appearance and the installation work is complicated. In addition, from an economic standpoint, there was a demand for an insulator that could support conductors and detect voltage at the same time.

Therefore, Figure 4. As shown in FIG.
A base metal fitting 30 is attached to the upper end of the insulator body 21 which is provided with a cavity 22 inside thereof, and an electrode plate 28 to which a lead wire 31 is connected is fixed above the cavity 22 with resin or the like. An insulator that detects the capacitance between the conductor 32 supported by the conductor support part 206 and the electrode plate 28 has been proposed, but such a conventional insulator
The insulator body 21 is generally made of the same material, such as ordinary porcelain, alumina porcelain, or epoxy resin, and is integrally molded from the viewpoint of insulation, weather resistance, mechanical strength, and cost. When soiled and wetted with (R), the capacitance fluctuates greatly due to an apparent increase in the electrode area, resulting in a disadvantage that the voltage measurement value becomes unstable with variations. That is, to explain this with reference to FIG. 4 and FIG. 5 showing an equivalent circuit, the insulator body 21
When the top of the electrode plate 28 is contaminated and moistened with electrolyte (R), the capacitance (C) between the electrolyte (R) and the electrode plate 28 is equal to the capacitance (C) when clean due to the contamination. Adding the capacitance (CR) due to the increase in electrode area, C=C1+C
R, so the variation in capacitance between clean and dirty conditions is the same, but the electrode area (electrolyte adhesion area) when dirty is much larger than the electrode area when clean. Therefore, in the capacitance that is proportional to the electrode area, the capacitance (
This is because the increase in CR) is significant and, therefore, the variation becomes extremely large. The present invention relates to an insulator completed for the purpose of eliminating the above-mentioned drawbacks, and the present invention will be explained in detail below with reference to illustrated embodiments.

Fig. 1 shows a tie-top type line post insulator as a first embodiment of the present invention, and 1 is provided with a hollow part 2 inside and a ceramic body fitting connected to the hollow part 2 at the top. An insulator body made of ordinary porcelain (relative permittivity 6) is provided with holes 3, and a ceramic body 5 whose main component is barium titanate (relative permittivity 1500) is placed in the hole 3 of the insulator body 1 with a conductor 11. The ceramic body 5 is provided with an upper surface portion on which a conductor support portion 6 is provided, by embedding it in a co-firing method so as to face each other, or by fitting and bonding it with an appropriate adhesive after firing. An electrode 7 for connecting a conductor is provided on the saw body by any means such as metal spraying, and an electrode 8 for connecting a lead wire is integrally provided on the lower surface facing the electrode 7. Connection electrode 8
The upper end of the lead wire 9 is connected to the insulator body 1, and a base metal fitting 10 is integrally fitted to the lower end portion of the insulator body 1 with cement or the like.

On the other hand, the second embodiment shown in FIG. The insulator body 1 is connected as an electrode 7 for connecting a conductor to the hole 3 for fitting the ceramic body in the insulator body 1 made of
A conductive metal layer 7a for making an electrical connection with a cap fitting with a conductor support part 6 mounted on the top of the body and an electrode 8 for connecting a lead wire are coated on the top and bottom surfaces of the saw body by metal spraying or other means. A ceramic body 5 mainly composed of strontium titanate (relative dielectric constant 260) provided in the insulator body 1 is fitted and integrated so as to be in contact with the conductor 11, and a base metal fitting 10 is attached to the lower end portion of the insulator body 1. The cap fitting with the conductor support part 6, which is fitted and fixed together with cement or the like and which is placed on the top of the insulator body 1 together with the electrode 7 for connecting the conductor described above, is a conductive metal layer 7a. It is fixed to the insulator body 1 with cement or the like, and is connected to the same potential as the insulator body 1.
The insulator body 1 and the insulator body 1 are constructed in this manner. The insulator body 1 is made of barium titanate, strontium titanate, or other insulators, which are provided on the body and have an electrode 7 for connecting a conductor on the upper surface and an electrode 8 for connecting a lead wire on the lower surface facing the electrode 7. The ceramic body 5, which is made of a material with a dielectric constant higher than that of the material, functions as a ceramic capacitor, and connects the conductor 11 of the line to the electrode 7 for connecting the conductor, and also serves as the electrode for connecting the lead wire. If lead wire 9 is connected to 8, conductor 1 of the line
1 is insulated from the ground, and the electrode area that determines the capacitance of the ceramic capacitor is the entire electrode 7 for connecting the conductor on the line side, and the entire electrode 8 for connecting the lead wire on the earth side. No matter how the diameter of the conductor 11 changes, the capacitance value required for voltage detection is always constant and can be reliably obtained. By doing so, it can be detected extremely easily.

Moreover, if the top of the insulator body 1 is contaminated or wetted by the electrolyte (RR) as shown by the chain line in FIG. As shown in Figure 2, the capacitance (C) is calculated by adding the capacitance (CR) of the insulator body 1 due to the increase in electrode area due to contamination to the capacitance (CO) of the ceramic capacitor. = CO + CR, and the variation in capacitance when clean and when dirty is as follows. However, since the material of the ceramic body 5 has a higher dielectric constant than the material of the insulator body 1, for example, the ceramic body 5 The insulator body 1
When the ceramic capacitor is made of a material having a relative dielectric constant A times as large as A, the capacitance (CO) of the ceramic capacitor is A times as large as the capacitance C1 of the insulator body 1, that is, CO=A-C1. If the CO of A. Clutsky et al. 4th
The variation of the conventional insulator shown in the figure A. Cl key? Compared to the conventional insulator, the variation can be reduced to
Therefore, the dielectric constant of the ceramic body 5 is 2 of that of the insulator body 1.
In the first embodiment, which is 5@, assuming that other conditions do not change, the error is the same as that of the conventional insulator. In addition, in the second embodiment in which the dielectric constant of the ceramic body 5 is 325 times that of the insulator body 1, the error can be reduced to ± that of the conventional insulator, and the insulator body 1 is free from dirt and moisture. It is possible to detect a stable voltage with few errors even when the voltage is low.

Furthermore, in the present invention, the material of the insulator body 1 is ordinary porcelain, alumina porcelain, epoxy resin, etc., as in the past, and only the conductor support portion is made of a ceramic body 5 with a high dielectric constant, so that it is better than conventional insulators. There is almost no difference in cost, and the shape can be achieved while maintaining dimensional compatibility with conventional insulators. In addition,
In the above two embodiments, the ceramic body 5 embedded in the top of the insulator body is most preferably made of ferroelectric ceramic such as barium titanate or strontium titanate. Any material may be used as long as it is high, and there are no restrictions on its shape or the means for providing both electrodes 7 and 8 on the ceramic body 5. Furthermore, there is no limitation on the means for providing the ceramic body 5 on the insulator body 1. Also, an electrode 7 for connecting a conductor and an electrode 8 for connecting a lead wire are provided on the ceramic body 5.
As long as the means is not electrically conductive between the two, it may be selected as appropriate depending on the shape of the insulator body 1 or its molding method, and there are no limitations. As is clear from the description of the above embodiments, the present invention not only insulates and supports a conductor from the ground in a power distribution line, but also accurately and easily detects the line voltage even when the insulator body is soiled. In addition, it has various advantages such as its cost and shape being almost the same as conventional insulators, and it contributes greatly to the development of industry.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing a first embodiment of the present invention, and a second embodiment of the present invention is shown in FIG.
The figure shows an equivalent circuit diagram when the insulator is soiled, FIG. 3 is a longitudinal sectional front view showing the second embodiment of the present invention, FIG. 4 is a longitudinal sectional front view showing an example of a conventional insulator, and FIG. 5 is a conventional insulator. There is an equivalent circuit diagram when the insulator is contaminated. 1: insulator body, 5: ceramic body, 7: electrode for connecting conductor, 8: electrode for connecting lead wire.

Claims (1)

[Scope of Claims] 1. A ceramic body having a dielectric constant higher than that of the material of the insulator body is integrally provided on the top of the insulator body in contact with the conductor, and a conductor connection is provided on the surface of the ceramic body in contact with the conductor. 1. An insulator characterized in that an electrode for connecting a lead wire is provided on the other end surface of the ceramic body to face the electrode. 2. The insulator according to claim 1, wherein the ceramic body is ferroelectric ceramic.