JPH03109705A - Transformer for gas insulation meter - Google Patents

Abstract

PURPOSE:To eliminate a restriction in a mounting attitude in a gas insulation sealing type switching device and to reduce and measure a transformer itself for a gas insulation meter by providing uneven parts each having a triangular state at both ends of an insulation sheet of an interlayer insulator for forming a high voltage coil. CONSTITUTION:When an insulation sheet 11 is wound while applying a tension P thereto after a coil wire 10 is wound, the sheet 11 is passed through triangular rollers in which vertexes become an acute angle, triangular uneven parts 12 are provided at both ends of the sheet 11, and the sheet is wound plural times. Further, a coil wire 10 of a next stage is aligned and wound. Similar operation is then repeated to form a high voltage coil. The position l of the parts 12 provided on the sheet 1 at this time is located at a distance of 10d or less from the end of the wire 10, and the height of the uneven part is 0.8d or more. Thus, a restriction in a mounting attitude in a gas insulation sealing type switching device is eliminated to contribute to reduction in size and measuring of the device, electric performance is improved to be easily handled.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention relates to a gas-insulated instrument transformer, and particularly to a gas-insulated instrument transformer equipped with a high-voltage coil composed of multiple cylindrical windings. Regarding transformers.

(Prior Art) Electromagnetic instrument transformers are generally used to measure voltage on power transmission lines and protect power transmission systems.

In particular, gas insulated closed switchgear (GI) has become popular in recent years.
Gas-insulated type transformers have also come to be used for instrument transformers installed in S). The configuration of such a conventional gas insulated instrument transformer is shown in FIG.

As shown in Figure 2, a low-voltage coil 2 is wound around one leg of an iron core 1 configured in a rectangular closed magnetic path, and a high-voltage coil 3 is wound coaxially with the low-voltage coil 2 around its outer periphery to form a voltage transformer. It consists of A high voltage shield 4 for controlling the electric field is attached to the outer periphery of the high voltage coil 3, and the high voltage shield 4 and the high voltage coil 3
The end of the winding is brought out to the outside of the container via an insulating spacer 5 at the same potential.

On the other hand, the voltage transformation section is housed in a container composed of a tank 6, a base 7, and an insulating spacer 5, and inside this container,
A gas insulated instrument transformer is constructed by enclosing and sealing an insulating gas 8 having electrically insulating properties such as SF.

By the way, the configuration of the high-voltage coil 3 is as shown in FIG. 3. On a winding form 9 made of an insulating material, a required number of coil wires 10 made of metal with low specific resistance, such as copper wire, are arranged along the winding form 9. After winding, the insulating sheet 11 is wound several times over the insulating sheet 1 while applying a constant tension P and simultaneously winding the coil wire 10a in the next stage.
The high-voltage coil 3 is formed with a so-called multiple cylindrical winding structure in which a required number of windings are made from the top of the coil 1 in the same manner as in the previous stage, and this is repeated several thousand to a hundred and several dozen times.

FIG. 4 shows a partially enlarged view of the end A (see FIG. 2) of the high voltage coil 3 constructed in this way.

As shown in FIG. 4, the high voltage coil 3 is composed of a combination of an insulating sheet 11 and a coil wire 10. In each stage, between the insulating sheet lla and the insulating sheet 11b of the next stage, a coil 10 is formed.
A gas gap δ close to the diameter d of is constructed.

(Problem to be solved by the invention) In the conventional gas-insulated instrument transformer as described above,
The frictional force caused by the tensile force P when winding the insulating sheet 11 acts as a resistance force against the external force acting in the cylindrical axial direction of the high voltage coil 3, and prevents the insulating sheets 11 from shifting in the cylindrical axial direction. Was.

However, since gas-insulated electrical equipment generally needs to be kept at a low moisture level for electrical insulation purposes, the insulating sheet 11 used in gas-insulated equipment is made of a non-hygroscopic material, such as a plastic film sheet.

These materials generally have a low coefficient of friction, and the tension P that can be applied to the insulating sheet 11 during coil forming is restricted, so the larger the mass of the high voltage coil 3, the more the high voltage coil 3 can withstand external forces with low acceleration. There is a possibility that the insulation sheets 11 that are attached to the cylinder may be displaced from each other in the axial direction of the cylinder, thereby impairing the electrical function.

This not only limits the handling and transportation of gas-insulated instrument transformers, but also restricts the handling and transportation of gas-insulated hermetic switchgear (GI
Since the mounting position on the gas insulated closed switchgear (GIS) is also limited, this has sometimes been an obstacle in making the gas insulated closed switchgear (GIS) more compact and weighable.

On the other hand, from an electrical point of view, the coil wire 10 repeatedly expands and contracts due to temperature changes, but since the upper and lower parts of the coil wire 10 are sandwiched between insulating sheets 11, the amount of expansion is limited to the amount of expansion caused by aligned winding in each stage. It is also possible that the coil wires at both ends are wrinkled and the coil wires at both ends protrude. If the coil wire protrudes, the electric field will concentrate in this protruding part, resulting in high stress, and both ends of the coil wire are insulated with composite insulation of insulating gas 8 and insulating sheet 11, which have different dielectric constants.
Coiled wire 10 in contact with gap δ of insulating gas 8 with low dielectric constant
This has been an obstacle to making gas-insulated voltage transformers smaller and more compact because the electric field is concentrated in the area.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and its purpose is to improve gas insulated closed switchgear (GIS).
By removing the mounting position restrictions on the gas insulated closed type switchgear (
The object of the present invention is to provide a gas-insulated instrument transformer that contributes to the downsizing and weighting of GI'S, has improved electrical performance, is downsized and weighed, and is easy to handle.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention is constructed by disposing a high voltage coil made of multiple cylindrical windings coaxially with a low voltage coil on an iron core. A gas-insulated instrument transformer in which a voltage transformation element is housed in a sealed container together with a pressurized insulating gas, in which triangular irregularities are provided at both ends of an insulating sheet of interlayer insulation that constitutes a high-voltage coil. It is.

(Function) As described above, the present invention employs an insulating sheet with triangular irregularities on both ends as an interlayer insulator, thereby making it easy to handle and install in a gas insulated closed switchgear (GIS). A gas-insulated voltage transformer with improved electrical performance can be obtained.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially enlarged view of a high-voltage coil of a gas-insulated instrument transformer according to an embodiment of the present invention.

In FIG. 1, after winding a coil wire 10 having a diameter d wound in an aligned manner, when winding an insulating sheet 11- while applying a tension P, the insulating sheet 11 is rolled onto a triangular roller whose apex angle is an acute angle. Triangular unevenness 12 is provided on both ends of the insulating sheet 11 (not shown) and the insulating sheet 11 is wound multiple times, and then the next stage of coil wire 10 is wound in alignment, and the same operations as described above are repeated. A high-voltage coil is manufactured. At this time, the position 1 of the triangular unevenness 12 provided on the insulating sheet 11 is set to be within 10a from the end of the coil wire 10, and the height h of the triangular unevenness is 0.8d or more.

With this configuration, in addition to the conventional friction force, the unevenness 12 on both ends of the insulating sheets 11 prevents the insulating sheets 11 from shifting against external forces acting in the cylindrical axis direction of the high-voltage coil 3. As a result, the mechanical strength of the gas-insulated instrument transformer can be improved, and restrictions on handling and installation posture in a gas-insulated hermetic switchgear (GIS) can be removed.

On the other hand, since the amount of protrusion of the coil wire due to thermal expansion of the coil wire 10 is also restricted by the unevenness 12 of the insulating sheet 11, concentration of the electric field applied to the protruding portion can be alleviated, and the vicinity of the end of the coil wire is insulated with a high dielectric constant. Because it is surrounded by sheet 11,
Electrical stress in the high voltage coil section can be reduced. Therefore, it becomes possible to reduce the size and weight of the gas-insulated instrument transformer itself.

[Effects of the Invention] As explained above, according to the present invention, in a high-voltage coil composed of multiple cylindrical windings, by providing triangular irregularities at both ends of an insulating sheet constituting the high-voltage coil, The mechanical and electrical performance has been improved, making it easier to handle gas-insulated instrument transformers, removing restrictions on the mounting position for gas-insulated sealed switchgear (GIS), and making gas-insulated instrument transformers easier to handle. Since the transformer itself can be made smaller and more meterable, gas-insulated hermetic switchgear (GIS
), it is possible to obtain a gas-insulated instrument transformer that contributes to miniaturization and metering.

[Brief explanation of drawings]

FIG. 1 is a partially enlarged view of a high voltage coil according to an embodiment of the present invention;
FIG. 2 is a front cross-sectional view of a conventional gas-insulated instrument transformer, FIG. 3 is a block diagram of the high-voltage coil shown in FIG. 2, and FIG. 4 is a partially enlarged view of the high-voltage coil shown in FIG. 3. 1... Iron core 2... Low voltage coil 3... High voltage coil 4... High voltage shield 5... Insulating spacer 6... Tank 7... Base 8... Insulating gas 9... Winding Type 10.10a...Coil wire 11, lla, 1lb-=Insulating sheet 12...Triangular unevenness (8733) Agent: Patent attorney Yoshiaki Inomata (and others)
1 person), Kaya 4 Figure

Claims (1)

[Claims] (1) A gas-insulated instrument transformer in which a voltage transformation element consisting of a high-voltage coil consisting of multiple cylindrical windings arranged coaxially with a low-voltage coil on an iron core is housed in a sealed container together with pressurized insulating gas. A gas-insulated instrument transformer according to the invention, wherein triangular irregularities are provided at both ends of the interlayer insulator constituting the high-voltage coil.