JP2624804B2 - Foil-wound transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention includes a sheet-shaped winding, a method for tightening the sheet-shaped winding, enhancement of short-circuit mechanical force, and vibration reduction during transportation. The present invention relates to a foil-wound transformer with improved winding supporting technology.

(Prior art) Sheet-shaped windings conventionally used for foil-wound transformers are widely used due to their excellent winding space factor, good potential distribution, and simple manufacturing. But limited to relatively small capacity transformers. For this reason, there has been little consideration for loosening of the winding due to short-circuit mechanical force, vibration during transportation, and temperature rise during operation, and it has been unnecessary to tighten and support the winding.

However, due to recent demands, the high voltage and large capacity of the sheet-shaped winding have been promoted, and the number of winding turns, the shape and dimensions have been expanded, and the short-circuit mechanical force has been strengthened. It has become necessary to improve the measures to prevent the winding from loosening due to the temperature rise and to improve the supporting structure of the winding itself.

This point will be specifically described with reference to a known foil-wound transformer shown in FIG. USP-4039990 is known as this type of transformer.

A metal sheet 2 and an insulating sheet 3 are superposed and wound on the outer periphery of the iron core 1, and a low-voltage winding 4 and a high-voltage winding 5 of a sheet winding type are wound thereon, and a hollow cooling duct 6 is wound around each of these windings. Built-in. Inside the cooling duct 6, Freon R
-113 and Fluorinert FC-75 are sealed and circulated by the pump 7 to remove the heat generated in the windings by the latent heat of vaporization of the refrigerant.
To condense. The liquefied refrigerant is stored in the refrigerant tank 10 and is further sent into the windings by the pump 7 to form a cooling system. The liquid guide pipe 11 constituting the cooling system is made of a metal such as stainless steel. The liquid guide pipe 11 and the cooling duct 6 are connected by an insulating pipe 12. In addition, the liquid guide pipe 11 is connected to the ground potential of the tank 13 and the like, while the cooling duct 6 is electrically connected to the same potential as the adjacent winding which is incorporated in the winding. Further, insulation of each part of the winding is ensured by an insulating medium 14 such as insulating oil or SF ₆ gas sealed in the tank.

(Problems to be Solved by the Invention) As described above, in this type of transformer, the cooling system in which the refrigerant for cooling flows and the insulating medium 14 for insulation are completely separated (separated). For this reason, it is generally called a separate type foil-wound transformer. Since this separate type foil-wound transformer utilizes the latent heat of vaporization of the refrigerant, it can be expected to have excellent cooling characteristics and is promising for large-capacity transformers. However, in actual use, there are the following problems. There is a point. That is, in this type of foil-wound transformer, the winding is tightened and supported on the leg of the iron core 1 by the winding force at the time of manufacturing the winding.

However, simply supporting by tightening only with the winding force does not support the winding in the radial and axial directions, so it is not possible to cope with changes in the shape and dimensions, and the mechanical force during a short circuit and the temperature rise during operation The transformer itself such as the windings and the cooling duct may be deformed and dropped due to the loosening of the windings due to the vibration and vibration during transportation. Therefore, when a material having excellent damping characteristics equivalent to that of rubber is used, lateral rigidity is weakened, and there is a possibility of vibration. In addition, when an insulator having a high hardness is used, the damping characteristics deteriorate, and it becomes difficult to reduce the vibration.

The present invention has been made in view of the above points, and its object is to sufficiently cope with mechanical force during short circuit, loosening of windings due to temperature rise during operation, and vibration during earthquake or transportation. Another object of the present invention is to provide a highly reliable foil-wound transformer capable of stably supporting a winding.

[Configuration of the invention]

(Means for Solving the Problems) The foil-wound transformer of the present invention is configured by arranging SF ₆ encapsulated anti-vibration springs using the spring constant of SF ₆ gas pressure in the circumferential direction of the winding end. The winding is supported in the axial direction, and the SF ₆ gas-filled anti-vibration spring is fixed to the tank or the iron core clamp.

(Operation) This feature is characterized in that a short-circuit mechanical force, vibration during an earthquake or transportation is attenuated, and the sheet-like winding is protected.

(Embodiment) An embodiment of the present invention will be described below with reference to FIG. 1 and FIG. Note that the same reference numerals are given to the foil-wound transformer and the first part in FIG. 3 and the description is omitted. Here, the case where the present invention is applied to a so-called separate type transformer so that the configuration of the present invention is most easily understood will be described.

By arranging SF ₆ enclosing anti-vibration spring 18 using the spring constant of SF ₆ gas pressure around the lower end of winding 17, winding 1
7 is supported in the axial direction, and the SF _6- enclosed anti-vibration spring 18 is fixed to an iron core fastening 19 or a tank. Also this SF ₆
A plurality of enclosed vibration-proof springs 18 are appropriately arranged in the circumferential direction.

According to the present embodiment having such a configuration, the SF ₆ gas-filled spring 18 at the end vibrates against the short-circuit mechanical force acting in the axial direction of the winding 17 and the vertical and horizontal vibrations during the earthquake and transportation during transportation. Can be attenuated. SF ₆ gas-filled spring 1
8 can provide a stable support structure by preventing the displacement of the winding due to a temperature rise during operation.

〔The invention's effect〕

According to the present invention described above, the radial dimension portion of the winding ends by using the spring constant of the SF ₆ gas pressure, and axial support by SF ₆ encapsulated anti-vibration spring, it if SF ₆ gas sealed antivibration Is fixed to the tank or iron core clamp, so that the short-circuit mechanical force of the sheet-shaped winding, the vibration during transportation is reduced, the displacement of the winding is prevented, and a stable winding support structure is provided. A highly reliable foil-wound transformer can be obtained.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of an essential part showing one embodiment of the present invention, and FIG.
FIG. 3 is a plan view of the same, and FIG. 3 is a sectional view of a conventional foil-wound transformer. 1 ... iron core 2 ... metal sheet 3 ... insulating sheet 4
... low voltage winding, 5 ... high voltage winding, 6 ... cooling duct, 7
... pump, 8 ... condenser, 9 ... cooling water pipe, 10 ... refrigerant tank, 11 ... liquid guide pipe, 12 ... insulating pipe, 13 ... tank, 14 ... insulating medium, 15 ... high pressure shield, 16 ...... basic insulation tube, 17 ...... winding, 18 ...... SF ₆ I be encapsulated anti-vibration, 19 ...
… Iron core clamp.

Continuation of the front page (72) Inventor Shigeo Shinjo 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Toshiba Hamakawasaki Plant (56) References JP-A-61-188915 (JP, A) 33615 (JP, U) Actually open Showa 50-77714 (JP, U)

Claims (1)

(57) [Claims] 1. A winding formed by laminating a sheet-like conductor and a sheet-like insulator on an iron core placed in a tank, in which an insulating medium is sealed, and cooling the inside of the winding along the winding axis direction. In a foil-wound transformer with a duct interposed, a plurality of SF ₆ gas-filled anti-vibration springs are provided at predetermined intervals in the circumferential direction at least at the upper and lower ends of the winding, and the winding direction is set in the axial direction. A foil-wound transformer supporting and fixing the SF ₆ gas-filled anti-vibration spring to the tank or the iron core clamp.