JPH0145686B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a corona shield ring device that also serves as an arcing horn, which is mainly installed in an insulator device for power transmission and transformation at ultra-high voltage or higher.

A corona shield ring device is known in which a corona shield ring is arranged outside a current-carrying part such as a conductor retaining part in an insulator device for power transmission and transformation to improve the corona characteristics of the insulator device, but conventional corona shield rings of this type The corona shield ring used in the device is usually a single ring made of a metal bar, so even if you try to improve the corona characteristics by enlarging the material diameter and outer diameter to match the magnitude of the target voltage, it will not work during drying. Only the corona properties are improved, but when water is poured, the surface area of the corona shield ring increases and the amount of water hitting the shield ring increases, and this water concentrates locally and falls, so the electric field concentrates on these water droplets and the corona increases. The characteristics do not improve by the extent to which the rings are enlarged, and depending on the structure, the corona characteristics may deteriorate. Therefore, we created a double ring that aims to disperse water droplets when water is poured by connecting two rings with material diameters that are smaller than this single ring in close proximity and in parallel to make the material diameter apparently equivalent to that of a single ring. Attempts have also been made to adopt the same ring structure, but even though the material diameter is apparently equivalent to a single ring,
Since the ring curvature diameter with respect to the opposing ground potential is smaller than the curvature diameter when a single ring is used, the corona characteristics are approximately 20% lower than the single ring even if the shielding effect of the other ring is expected. It was lower than when using . Therefore, if you want to use double rings of the same diameter, instead of lining up two rings with half the material diameter of a single ring, double rings with a material diameter 20 to 30% larger. It is not possible to obtain the same corona properties as a single ring unless it is used in a single ring, and if it is to be applied to a high voltage insulator device, the material diameter of each ring will inevitably increase, which will increase the weight. As mentioned earlier, there is a problem in that the corona characteristics deteriorate due to the concentration of water droplets during water injection.

The present invention was completed with the aim of providing a corona shield ring device that solves the above-mentioned problems, and the illustrated embodiment will be described in detail below.

1 and 2 show a first embodiment in which the present invention is applied to a horizontal quadruple tension insulator device. A conductor yoke 5 is connected to the tip via a connecting fitting 4.
The insulator device main body 6 to which is connected is provided with a corona shield ring chain A consisting of eight corona shield rings so as to surround the outside of the energized parts at the tips of all the suspended insulators 3 corresponding to the conductor retaining parts. but,
This corona shield ring chain A has a well-known single ring 7 except for the electric field concentration part, whereas the electric field concentration part, that is, the suspension insulators 3 and 3 on both sides.
A double corona shield ring 8 is formed by sequentially overlapping two rings 8a and 8b of different sizes with similar external shapes, and each corona shield ring 8 has the largest diameter ring 8a. Similar to the other single ring 7, the ring 7 is placed close to the outside of the charging section. Further, this corona shield ring 8 is formed of a solid body or a hollow round bar material, and the ring diameter difference between the adjacent rings 8a and 8b is determined by the ring 8 on the larger diameter side.
The material diameter of the ring 8b on the small diameter side is set to be 0.8 to 1 times the material diameter on the large diameter side, and the material diameter of the adjacent rings 8a and 8b is The parallel dividing lines A and B passing through the centers of the rings 8a and 8b are overlapped such that the distance between them is 0.5 to 1.5 times the material diameter of the larger diameter ring 8a.

The device constructed in this way is similar to conventional corona shield ring devices of this type in that the corona characteristics of the insulator device are improved by the corona shield ring placed outside the energized portion such as the conductor holding portion. However, in the present invention, especially the corona shield ring 8 disposed outside the electric field concentration part
Since a special ring is used in which a plurality of rings 8a and 8b of different sizes with similar external shapes are sequentially superimposed, when compared with a conventional single ring,
Not only does the double ring have the advantage of being able to disperse water droplets during water injection and improve the corona characteristics during water injection, but it also has the advantage of being double rings of the same diameter. It has the following excellent properties. In other words, when rings of the same diameter are doubled, the surface electric field strength at the end of the ring is approximately determined by the radius of curvature of the end of the ring located on the outside, that is, on the opposing ground potential side.
Although the electric field mitigation effect of the other ring is extremely small, if the outer diameter of the ring 8b on the earth side is made small as in the present invention, the electric field strength at the end of the ring relative to the earth side will be as shown in Fig. 3. As shown, since it is determined by the radius of curvature R, which is larger than it appears, both rings 8a and 8b work more effectively than double rings of the same diameter, even for rings made of the same material diameter, and the electric field at the end of the ring is relaxed. Therefore, the corona characteristics can be significantly improved. This means that if the required corona properties are the same as those of conventional corona shield rings, the diameter of each ring material can be reduced by the amount of the electric field effect described above, and the required corona properties can be reduced by the same diameter. Therefore, in anticipation of the above-mentioned electric field mitigation effect, only the ring 8b on the side facing the ground side can be made thinner as shown in Fig. 5, which not only improves the corona characteristics but also reduces the size and weight of the entire device. Also, it is possible to facilitate the installation work. Regarding the connection configuration of the corona shield ring 8, the horizontal dimension difference (B-A) and vertical dimension difference (ba-a) between the small-diameter side ring 8b and the large-diameter side ring 8a are When the corona noise level is α and the corona generation voltage during drying is β, α
The standard value of is 1.0 for 90dB at the normal ground voltage, and the standard value for β is 1.0 for 1.2 times the normal ground voltage.The horizontal axis is the dimensional difference (B-A) and (ba-a), and the vertical axis is α. As is clear from the corona characteristic curve shown in Fig. 9, which takes the multiple K of the reference value of β, the allowable value of α is 1.0 in order to satisfy the target corona performance of the insulator device.
It is necessary to keep both α and β within an allowable range, such that the tolerance value of β is 1.0 or more. Specifically, if the material diameter of the shield ring is D, the dimensional difference (B-A), (b- When a) is at the end of the material diameter (D), the shielding range of the larger diameter ring 8a falls within the corona shielding range of the smaller diameter ring 8b, and the corona characteristics are almost the same as those of the ring 8b, resulting in a visible corona. The generated voltage is less than 1.2 times the reference voltage, that is, the normal ground voltage. Furthermore, during rainy weather, the reference level for corona noise interference, that is, the normal ground voltage.
Corona discharge of 90dB or more occurs. Also, the dimensional difference between ring 8b and ring 8a (B-A), (b-a)
If the diameter exceeds twice the material diameter, the ring 8a on the large diameter side
Since the corona shield range of ring 8b on the small diameter side falls within the corona shield range of ring 8b, the corona characteristics are almost the same as those of ring 8a, and therefore the visible corona generation voltage is 1.2 times or less of the reference voltage, that is, the normal ground voltage. Furthermore, during rainy weather, a corona discharge of 90 dB or more occurs at the reference level for corona noise interference, that is, the normal ground voltage. Therefore, adjacent rings 8
It is preferable that the difference in ring diameter between a and 8b is larger than the ring material diameter and within a range not exceeding twice that. Next, regarding the ring spacing (Y), as is clear from the graph in Figure 10, which shows the allowable range of corona characteristics for the ring spacing (Y) under the same conditions as mentioned above, the ring spacing (Y) is the same as the material diameter. When it is less than half, the shielding effect of the ring 8b on the small diameter side is lost and the characteristics of the ring 8a on the large diameter side become independent, and if the ring spacing (Y) exceeds 1.5 times the material diameter, the shielding effect of the ring 8b on the small diameter side is Since it is a characteristic of 8b alone, the visible corona generation voltage during drying is 1.2 times or less of the reference voltage, that is, the normal ground voltage. Furthermore, during rainy weather, corona discharge of 90 dB or more occurs at the reference level for corona noise disturbance, that is, the normal ground voltage.
Therefore, the distance between adjacent rings is equal to the material diameter.
The range is preferably 0.5 to 1.5 times. Also,
Although the above embodiment is applied to a horizontal quadruple tension insulator device, it can also be applied to a double suspension insulator 3 as shown in FIG. 11, or a corona shield ring as shown in FIG. A similar effect can be expected when the ring is made up of three or more rings. Further, in the description of the above embodiment, it is assumed that each ring is formed integrally, but a split ring may also be used as shown in FIG. 13.

As is clear from the description of the embodiments described above, the present invention provides a corona shield ring device in which a corona shield ring is disposed outside a current-carrying part such as a conductor retaining part of an insulator device. It has a special structure in which multiple rings of different sizes with similar shapes are stacked one on top of the other in order to exhibit excellent corona characteristics.The advantage is that it is smaller and lighter and easier to install. Together with this, the contribution to the development of the industry is extremely large.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway plan view showing a first embodiment of the present invention, FIG. 2 is a view taken along arrow A-A in FIG. 1, and FIG. 3 is a partially cutaway front view of a corona shield ring. 4
Figure 5 is a partially cutaway front view showing another embodiment of the double corona shield ring, Figure 6 is the same top view, and Figure 7 is an implementation in which the corona shield ring is triple-layered. A partially cutaway front view showing an example;
FIG. 8 is a plan view, FIGS. 9 and 10 are graphs showing the allowable range of corona characteristics, FIG. 11 is a partially cutaway front view showing the second embodiment of the present invention, and FIG.
The drawings are a view taken along the line B--B in FIG. 11, FIG. 13 is a partially cutaway front view of the corona shield ring used in the second embodiment, and FIG. 14 is a plan view of the corona shield ring used in the second embodiment. 8: Corona shield ring, 8a, 8b: Ring.

Claims (1)

[Claims] 1. A corona shield ring formed by sequentially overlapping a plurality of rings of different sizes with similar external shapes, with the ring with the largest diameter placed close to the outside of a current-carrying part such as a conductor retention part. A corona shield ring device, in which the ring spacing (Y) between adjacent rings is 0.5 to 1.5 times the material diameter of the larger diameter ring, and
A corona shield ring device characterized in that the ring diameter difference between adjacent rings is larger than the material diameter of the larger diameter ring and does not exceed twice that. 2. The corona shield ring device according to claim 1, wherein the corona shield ring is composed of two rings of similar size and small size and made of a round bar material and having similar external shapes. 3. The corona shield ring device according to claim 1, wherein the corona shield ring is composed of three or more rings of different sizes and having similar external shapes and made of round bar material. 4. The corona shield ring according to claim 1, 2, or 3, in which the material diameter of the smaller diameter ring among the adjacent rings is 0.8 to 1 times the material diameter of the larger diameter ring. Device.