Dry-type air-core reactor preparation mould provided with air gaps of fixed size and sample preparation method

Abstract

The invention relates to a dry-type air-core reactor preparation mould provided with air gaps of a fixed size and a sample preparation method. A mould composed of a cover plate and a bottom plate is utilized to conduct sample preparation, two same enamel insulated aluminum wires are embedded into a doubling groove of a mould groove, a gap sheet is utilized to be inserted into the position betweenthe two aluminum wires to construct the air gaps of the fixed size, the groove depth and the groove width of a through groove in the bottom plate are equal, the groove depth of the doubling groove isequal to the groove depth of the through groove, the groove width of the doubling groove is equal to the sum of double of the groove width of the through groove and the thickness of the gap sheet, andbubbles in epoxy resin glue are effectively removed through three times vacuumizing operation. Compared with the prior art, the dry-type air-core reactor preparation mould provided with the air gapsof the fixed size and the sample preparation method have the advantages that the insulation deformation damage of line outgoing in the sample demoulding process is avoided, unevenness of interturn gaps is avoided, increasing of the interturn gaps which are brought in an original sample heating and shaping process is avoided, and discharging of the bubbles inside the epoxy resin is more facilitated.

Description

technical field [0001] The invention relates to a preparation method of a dry-type air-core reactor, in particular to a preparation mold and a sample preparation method of a dry-type air-core reactor with an air gap of a fixed size. Background technique [0002] As a kind of reactive power compensation equipment and smooth wave device, dry-type air-core reactor is widely used in AC and DC transmission systems, and its working reliability is directly related to the operation safety of the power grid. Statistics show that more than 60% of the faults of dry-type air-core reactors are caused by inter-turn short circuits caused by winding insulation breakdown, and these insulation breakdown accidents are often caused by inter-turn insulation defects. Therefore, the study of the electrical performance of the interturn insulation of dry-type air-core reactors has positive significance for the design and maintenance of dry-type air-core reactors and the safe operation of reactors. ...

AI Technical Summary

Problems solved by technology

When the inter-turn sample is made by binding and shaping method, due to the high viscosity of the epoxy resin before curing, the air bubbles may be attached to the nylon cable tie during the vacuum defoaming process and cannot be discharged smoothly

However, in the previous mold setting method, the parallel part of the wires is placed in a relatively wide groove. Since the epoxy resin vacuum degassing process is relatively slow, it is easy to cause deep bubbles to stay in the epoxy resin during the floating process due to the curing of the resin. internal

All of the above situations may lead to air bubbles remaining between the turns in the prepared sample, and then partial discharge first occurs at the air bubbles in the sample withstand voltage test, which seriously affects the effectiveness of the test results.

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