SU1737530A1 - Capacitive ring of high-voltage transformer winding - Google Patents

Abstract

SUMMARY OF THE INVENTION: The device comprises a toroidal core 1 with an electrode 2 made of turns of an uninsulated metal tape. The gap 6 is made between the first and the last turns of the tape. The adjacent turns adjoin each other only at points 3 located on the circumference of the inner diameter of the core. Insulating wedge-shaped gaps 4 are made between adjacent turns. An element 5 connecting the electrode to the winding is attached to one of the turns. The presence of gaps 4 eliminates eddy currents in the electrode, and the presence of contact points 3, electrical oscillations between coils 1 or less.

Description

The invention relates to electrical engineering and can be used in the manufacture of high voltage transformers and reactors connected to a power line and exposed to thunderstorm effects.

- A capacitive ring of a high-voltage transformer winding is known, which contains a dielectric core electrode on the surface, formed by turns of insulated metal tape with a gap between the first and last turns, and the electrode connection element to the winding, and the turns of the electrode are welded.

A disadvantage of the known technical solution is the increased labor intensity of manufacturing, since it is necessary to isolate the tape and solder the coils between them. Insulating the tape eliminates eddy currents in the electrode, and soldering the coils eliminates electrical oscillations during thunderstorm overvoltages.

Closest to the present invention is a capacitive ring winding of a high voltage transformer containing a dielectric core, an electrode on the surface of the core formed by turns of a metal tape with a gap between the first and last turns, and an element connecting the electrode to the winding.

In this ring, the element connecting the electrode to the winding is placed necessarily on the middle turn of the tape, and the tape is isolated

In the known construction, soldering between turns was eliminated, however, it was necessary to isolate the metal tape to eliminate eddy currents in the electrode and to determine the average turn of the electrode to avoid electrical oscillations of the turns that saves undesirable labor costs in its manufacture.

The purpose of the invention is to reduce the labor intensity and the placement of the connection element on any turn.

cl

WITH

vj

GJ VJ SL

with about

The goal is achieved by the fact that in a capacitive ring winding of a high voltage transformer containing a dielectric core, an electrode on a tape surface with a gap between the first and last turns, and an electrode connecting element to the winding, according to the invention, the turns are made of non-insulated tape and placed on the core that are adjacent to each other in succession at points on the inner surface of the core, while insulating gaps are formed at the other points of the radial size of the core between the turns.

The drawing shows a capacitive ring.

The capacitive ring winding of a high-voltage transformer contains a dielectric core 1, for example, from a cardboard of 8–20 mm thick, and an electrode on the surface of the core, formed by coils 2 of an uninsulated metal tape (for example, copper, 0.1–0.2 mm thick). mm, width 20-40 mm). The electrode is placed on the surface of the core so that the coils 2 adjoin one another successively at points 3 on the inner surface of the skeleton, and in the remaining points of the radial size of the core between the coils form insulating gaps 4. Element 5 connecting to the winding at point A can be placed in any turn. A gap of 6 between the first and last turns excludes a short circuit between them.

When acting on point A of the winding of a thunderstorm overvoltage, the potential of all the electrode coils is the same and the electric oscillations of the coils are absent, since they are shorted at points 3 on the inner diameter of the ring db. In the operating mode, the eddy currents in the electrode do not occur as the coils are isolated from one another by insulating gaps 4 and do not form a solid.

Tests have shown that the presence of insulating gaps U. equal

and u (-1)

QB

where U is the width of the insulating gap:

ni is the width of the tape;

dB is the internal diameter of the ring;

dH is the outer diameter of the ring, does not lead to a distortion of the electric field, if U is not more than 2-3 mm, which is ensured by choosing the width of the tape t.

50

five

0 5 0

50

five

0

five

The number of turns, in contrast to the known constructions, can be increased, and the width of the strip g, respectively, reduced, since all the turns are shorted and do not create inductance, which causes electrical oscillations of the turns.

The main technical contradiction (it is necessary to short the coils, but they should not close and create a solid body) in the analogue was solved by isolating the tape and soldering the coils with the shank.

In a known ring, it is solved by insulating the tape and placing the connection element only on the middle turn.

In the proposed technical solution, this contradiction is solved by placing the turns on the annular dielectric core with the detection and use of the geometric properties of the core and the tape. The length of the outer circumference of the skeleton per l (d -dB) is greater than the length of its inner circumference. This allowed galvanic abutment of the turns only on the inner circumference and at the same time creating insulating gaps between the remaining points of the adjacent turns without applying insulation on the tape.

The formation of these insulating gaps is sufficient to isolate between adjacent turns (between adjacent overgrown turns, the overvoltage is zero) and is acceptable for the picture of the electric field near the surface of the capacitive ring.

The economic effect is determined by reducing by 1 hour the time spent on one ring (excluding the operation of isolating the tape, counting turns, etc.) and the total number of rings in production, which is up to a thousand units per year.

Claims (1)

Invention Formula A capacitive ring winding of a high-voltage transformer containing a dielectric core, an electrode on the core surface formed by turns of a metal tape with a gap between the first and last turns, and an electrode-to-winding element, so as to reduce the complexity and placement of the connection element any coil, the coils are made of uninsulated tape and placed on the skeleton in such a way that they are adjacent one to another successively at points on the inner surface of the core, while in the rest points of radial size of the core between the coils are formed by insulating gaps.