SU1354341A1 - Winding of high-voltage electric machine - Google Patents

Abstract

The invention relates to electrical engineering, in particular to electrical engineering. The purpose of the invention is to increase the operational reliability of the machine by increasing the stability of the properties of the protective coating under conditions of exposure to higher humidity at voltages above 18 kV. In the first section, the coating is made in the form of an enamel layer with a filler of black carborundum with a dispersion of 20-28 μm and a filler content of 75-80 wt.h. to the mass of enamel. The length of the first section is 80-120 mm. The introduction of black carborundum into the enamel composition at the site provides, for given dimensions and test voltage up to 60 kV, the value of specific Q losses in the protective coating is not more than 10 W / cm. 1 il. (L coed 4 CO 4

Description

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The invention relates to the field of electrical engineering, in particular to the design and manufacture of electrical machines.

The purpose of the invention is to increase the operational reliability of the machine by increasing the stability properties of the protective coating of the winding under conditions of exposure to high humidity at voltages above 18 kV.

The drawing shows a portion of a winding with a protective coating preventing the development of corona and surface discharges.

Conductor 1 with insulation 2 is laid in the slot of the magnetic circuit 3. A conductive coating 4 is applied over the insulation 2. The protective coating consists of two sections. The first section of the coating 5 is adjacent to the magnetic conductor 3 and is galvanically connected to it through a conductive coating 4. The second section of the coating 6 is adjacent to the first section 5 and is galvanically in contact with it.

In the first section 5, the coating is made in the form of an enamel layer with a black carborundum micropowder filler with a dispersion of 20-28 μm and a filler content of 75-80 wt.h. to the mass of enamel. The length of the first section is 80-120 mm.

In the second section 6, the coating is made in the form of an enamel layer with a filler of micropowder of green carborundum with a dispersion of 20-28 μm and a filler content of 75- 80 wt.h. To the mass of enamel. The length of the second section is 250 mm.

When a high voltage is applied to the conductor 1 relative to the magnetic conductor 3, in particular a test voltage of 60 kV, along the surface of the insulation 2 a tangential component field acts, leading to the development of corona and sliding discharges, which destroy the insulation. a two-stage protective coating of semiconducting material makes it possible to equalize the distribution of the electric field strength along the insulation surface and to exclude the indicated processes under the machine’s operating voltage and su

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significantly reduce their intensity at the test voltage. The introduction of black carborundum into the enamel composition at section 5 provides, for given sizes of sections 5 and 6 and the test voltage up to 60 kV, the value of specific losses in the protective coating is not more than 10 W / cm. At the indicated value of specific losses in the coating, heat is released, which is insufficient for the development of thermal instability and the formation of conducting tracks;

The use of the proposed coating in the windings of powerful electric machines with a working voltage of up to 27 kV makes it possible to exclude the corona in the frontal parts of the winding in the operating mode and, thereby, to increase the current.

service life of the insulation

The high-winding electric machine winding J contains an insulated conductor with a semiconductive coating located in the groove of the magnetic conductor at the conductor exit from the groove consisting of two consecutive sections, one of which is adjacent to the magnetic conductor and is galvanically connected to it and contains a layer of enamel with a filler carborundum micropowder with a dispersion of 20-28 microns and the content of the latter 75-80 wt.h. when the length of the section is 80-120 mm, and the second section is adjacent to the first one, it is galvanically connected to it and is made in the form of an enamel layer with a filler of micropowder green carborundum with a dispersion of 20-28 μm and the content of the last in enamel 75-80 wt.ch., characterized in that, in order to increase the operational reliability of the machine by increasing the stability of the properties of the protective coating under conditions of exposure to high humidity at voltages above 18 kV, B black microborder was introduced as enamel filler in the first section of the coating NDA.

Claims (1)

TOK. Claim The winding of a high-voltage electric machine, containing an insulated conductor located in the groove of the magnetic circuit, an insulated conductor with a semiconducting coating at the outlet of the conductor from the groove, consisting of two consecutive sections, one of which is adjacent to the magnetic circuit and galvanically connected to it and contains an enamel layer filled with carborundum micropowder with a dispersion of the content of the latter at a section length of 80-120, a swarm section adjoins to a galvanically connected with pollen in the form of an enamel layer with a micropore filler shka green carborundum with dispersity of 20-28 um and a content of enamel in 7580 parts by weight, featuring the fact that, in order to increase the reliability of machine-translational stability Vyshen protective properties. In case of exposure to high humidity at voltages above 18 kV, b, micropowder of black carborundum was introduced in the first coating area as an enamel filler. 20-28 μm and 75-80 wt.h mm, and the first, him and you. I operate by