JPH0677032B2 - Current transformer for light meter for gas insulated switchgear - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention is an AC instrument for optical instruments using the Faraday effect, and a current transformer sensor detection section near a main circuit conductor of a gas insulated switchgear. The present invention relates to a current transformer for an optical measuring instrument for a gas-insulated switchgear, which transmits optical information from the device to an insulating gas space in a closed container.

(Prior Art) Conventionally, as a current transformer for an optical instrument for a gas-insulated switchgear of this kind, an example of FIG. 3 (first example) and an example of FIG. 4 (second example) described below. Then, there is an example (third example) in FIG.

FIG. 3 shows the high-voltage main circuit conductor 2 arranged in the insulating gas space S in the closed container 1, the current transformer glass sensor detection unit 3
Is supported by the glass sensor detection part holding seat 4, and the closed container 1 at a position facing the current transformer glass sensor detection part 3
The light emitting / receiving head 5 is fixed through the wall surface of the. In this case, the light emitting / receiving head 5 and the current transformer glass sensor detection unit 3
The optical space transmission line 6 is formed between the above and. Reference numeral 8 is a light emitting side optical fiber connected to the light emitting / receiving head 5 via a gas sealed fiber terminal 7, and 9 is a light receiving side optical fiber connected to the light emitting / receiving head 5 via a gas sealed fiber terminal 7.

4 and 5 both show that in the configuration as shown in FIG. 3, the optical axis shift in the optical space transmission line 6 is affected by the vibration of the switch provided in the gas insulated switchgear. It is an example in the case where it is used in an application in which the error of the optical current transformer based on it is a problem. That is, FIG. 4 shows that the current transformer glass sensor detection unit 3 is held at one end of the tapered insulating cylinder 10, and the other end of the insulating cylinder 10 is fixed to the inner wall surface of the hermetically sealed container 1, whereby the light emitting / receiving head 5 is provided. This is an example in which the relationship between the optical axis of the optical space transmission path 6 and the optical axis of the optical space transmission path 6 does not change. FIG. 5 shows that the current transformer glass sensor detection unit 3 is held at one end of the hollow post type insulating spacer 11, and the other end of the insulating spacer 11 is installed at the installed potential side closed container 1.
In this example, the relationship between the optical axis of the light emitting / receiving head 5 and the optical axis of the optical space transmission line 6 is prevented from fluctuating.

(Problems to be Solved by the Invention) In the example shown in FIG. 3, since the optical axes of the optical space transmission 6 between the optical current transformer glass sensor detection unit 3 and the light emitting and receiving head 5 are aligned, There are the following problems.

The main circuit conductor 2 to which the sensor detection unit 3 is attached is bent by vibration during an earthquake or operating vibration of the switch, and the optical axis between the light emitting / receiving head 5 and the sensor detection unit 3 is deviated, which causes the output of the optical current transformer. Error occurs.

When a large accident current flows through the main circuit conductor 2, the main circuit conductor 2 is deflected by the electromagnetic mechanical force, and the light emitting / receiving head 5
The optical axis between the and is shifted, which causes an error in the output of the optical current transformer.

When mounting the sensor detection unit 3 on the main circuit conductor 2, it takes time and effort to adjust the optical axis between the sensor detection unit 3 and the light emitting / receiving head 5.

On the other hand, in FIGS. 4 and 5, the sensor detector 3 is held at one end of the insulating cylinder 10 and the hollow post type insulating spacer 11, and the other end is a rigid body between the light emitting and receiving head 5. Since it is fixed to the inner wall surface of a certain closed container 1, the optical axis of the optical space transmission 6 can be integrated, and the problem of FIG. 3 described above can be solved.

However, in FIGS. 4 and 5, the insulating cylinder 10 and the hollow post type insulating spacer 11 must be specially provided in order to provide the optical current transformer including the sensor detection unit 3 and the light emitting / receiving head 5. Insulating cylinder 10, hollow post type insulating spacer
In addition to the provision of 11, in order to maintain the creeping dielectric strength inside the closed container 1, it is sufficient if the insulation dimension L1 as shown in the figure can be secured between the closed container 1 and the main circuit conductor 2,
Insulation dimension L2 longer than insulation dimension L1 to provide an optical current transformer
Therefore, there is a problem that the outer shape of the hermetically sealed container 1 at the portion where the optical current transformer is inserted becomes large in practice.

Therefore, the present invention eliminates the output error of the optical current transformer due to the optical axis shift of the optical space transmission line due to an earthquake or operating vibration of the switch, and further, a special insulating cylinder for supporting the optical current transformer detection unit and An object of the present invention is to provide a current transformer for an optical instrument for a gas insulated switchgear, which can be downsized as a whole without providing a hollow post-type insulating spacer.

[Means for Solving the Problems] (Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention fills a cylindrical hermetic container with an insulating gas and insulates the main circuit conductor with a conical disk. The spacer is electrically connected by a conductor connecting portion provided in the center of the spacer and mechanically supported, and is provided with a light emitting / receiving head and an optical current transformer sensor detecting portion for measuring an energizing current of the main circuit conductor. Among the effects, in a current transformer for an optical measuring instrument for a gas insulated switchgear, which can be measured by a photocurrent sensor that measures a magnetic field of a current to be measured by using a Faraday effect, the optical current transformer sensor detection unit is the insulating spacer. It is attached to a conductor connecting portion provided in the central part of the device, and the light emitting and receiving head is configured to be fixed through the wall surface of the hermetically sealed container through an optical space transmission line at a position facing the optical current transformer sensor. thing A.

(Operation) According to the present invention, since the optical current transformer sensor detection unit is directly fixed to the conical disk-shaped insulating spacer that supports the main circuit conductor, the optical current transformer sensor detection unit and the light emitting / receiving head The output error of the optical current transformer due to the optical axis shift of the optical space transmission between the optical current transformer and the optical current transformer can be eliminated. Since it is not necessary to provide post-type insulating spacers, the overall size can be reduced and the structure can be simplified.

(Example) Hereinafter, the Example of this invention is described with reference to drawings. FIG. 1 is a longitudinal sectional view showing only a main part of one embodiment of the present invention, and FIG. 2 is a sectional view taken along the line II-II of FIG. 1 and seen in the arrow direction. Here, the same parts as those in FIG. 3 to FIG. The gas-insulated switchgear is provided with an insulating spacer 20 as shown in the figure for supporting the main circuit conductor 2 and electrically connecting it. The insulating spacer 20 has a conical disk shape, a conductor connecting portion 21 is embedded in a through hole 20a formed in a central portion thereof, and a plurality of bolt insertion holes 20b are formed in a peripheral portion thereof. There is. The container units 1A and 1B, which are composed of, for example, two cylindrical bodies that constitute the closed container 1, have flanges 1Af and 1Bf formed at their ends, respectively.
In the bolt insertion hole 20 formed in the insulating spacer 20.
Bolt insertion holes 1Afh, 1Bfh are formed at positions corresponding to h, the peripheral edge of the insulating spacer 20 is sandwiched between the flanges 1Af, 1Bf, and bolts 22 are inserted in these bolt insertion holes 1Afh, 1Bfh, 20h. The bolt 23 has a nut 23 at the protruding end.
The container units 1A, 1B and the insulating spacer 20 are integrally connected by this.

Then, the bottomed cylindrical conductor connection seat 24 is fixed or fixed to one end surface of the conductor connection portion 21. Conductor connection seat 24
Tapered 2B formed on the tip of main circuit conductor 2B inside
a is configured to be slidable in the axial direction, and a contactor insertion groove 24a for inserting an annular current contactor 25 is formed on the inner peripheral surface of the conductor connection seat 24 that contacts the outer peripheral surface of the tapered portion 2Ba. ing. A glass sensor detection part holding seat 4 is provided on the outer peripheral surface of the conductor connection seat 24, whereby the optical current transformer glass sensor detection part 3 is supported and fixed.

Then, the container unit facing the glass sensor detection unit 3
An opening 1Bw is formed on the wall surface of 1B, a light emitting / receiving head cover 26 is fixed to the opening 1Bw, a light emitting / receiving head 5 is fixed to the light emitting / receiving head cover 26, and a gas-sealed fiber terminal 7 is fixed through. The sealed fiber terminal 7 is provided with a light emitting side optical fiber 8 of the light emitting and receiving head 5,
The light receiving side optical fiber 9 is inserted. Insulation spacer 20
The end portion of the main circuit conductor 2A is fixed to the other end surface of the.

With this structure, the current contact 25 is only in flexible contact with the main circuit conductor 2B.
The glass sensor detection unit 3 is independent from the mechanical vibration and mechanical stress generated in 2B. In addition, the insulating spacer 20 is
Since it is firmly fixed to the closed container 1 by the flanges 1Af and 1Bf of the container units 1A and 1B, the optical space transmission axis relationship between the light emitting / receiving head 5 fixed to the closed container 1 and the glass sensor detection unit 3 Is firmly held, and it is possible to completely suppress the output error of the optical current transformer caused by the fluctuation of the received light amount due to the optical axis shift.

[Effect of the Invention] According to the present invention described above, the optical current transformer sensor detection unit is
Since it is directly fixed to the conical disk-shaped insulating spacer that supports the main circuit conductor, the optical current transformer with the optical axis shift of the optical space transmission between the optical current transformer sensor detection part and the light emitting / receiving head is The output error can be eliminated, and it is not necessary to provide an insulating cylinder or a hollow post type insulating spacer that was conventionally required to support the optical current transformer sensor detection section. A current transformer for an optical instrument for a gas insulated switchgear that can be simplified can be provided.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing only a main part of an embodiment of a current transformer for an optical meter for a gas insulated switchgear of the present invention, and FIG.
Sectional views taken along the line II-II and viewed in the direction of the arrows, and FIGS. 3 to 5 are sectional views of essential parts showing different examples of conventional current transformers for gas-insulated switchgear optical instruments. Is. 1 ... Airtight container, 2 ... Main circuit conductor, 3 ... Optical current transformer glass sensor detector, 5 ... Light emitting / receiving head, 6 ... Optical space transmission line, 20 ... Insulating spacer, 21 ... Conductor Connection, 24
...... Conductor connection seat, 25 ...... Conductive contact.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takeshi Yokota 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Headquarters office (72) Inventor Masayuki Kosakada 1-1-1, Shibaura, Minato-ku, Tokyo Toshiba Corporation Head Office

Claims (1)

[Claims] 1. A cylindrical hermetic container is filled with an insulating gas, and a main circuit conductor is electrically connected by a conductor connecting portion provided at the center of a conical disk-shaped insulating spacer, and mechanically. A photocurrent sensor that supports and measures the current flowing through the main circuit conductor, and includes a light emitting / receiving head and an optical current transformer sensor detection unit, and measures the magnetic field of the measured current using the Faraday effect in the magnetic field optical effect. In a current transformer for a gas insulated switchgear for optical instruments which can be measured with, the optical current transformer sensor detection part is attached to a conductor connection part provided in a central part of the insulating spacer, and the light emitting / receiving head is A current transformer for an optical instrument for a gas insulated switchgear, which is fixed through the wall surface of the hermetically sealed container through an optical space transmission line at a position facing the optical current transformer sensor.