Iron core excitation device and method for seeking and recovering breakdown range of pouring coil

Abstract

The invention discloses an iron core excitation device and a method for seeking and recovering breakdown range of a pouring coil. The iron core excitation device is characterized in that a first ironcore post, a second iron core post, a third iron core post and a movable iron core post which have square cross sections form a closed magnetic path, a C-shaped structure is formed at overlap joints among the first iron core post, the second iron core post and the third iron core post by right-angle gaps repeatedly arranged in staggered way, an excitation coil is attached onto a coil wound from the third iron core post and is uniformly arranged along a length direction of the third iron core post, the turns of the excitation coil is in a way that cross section of the iron posts can normally run under rated voltage and normal magnetic flux density, and when the iron core excitation device is closed, contact surfaces between the movable iron core post and the first iron core post and betweenthe movable iron core post and the second iron core post are smoothly attached to form the iron core excitation device. The method is used for seeking a breakdown fault position among segments, layers and turns of an epoxy pouring coil, the complicated process of repeatedly disassembling and assembly a transformer is reduced, the fault position can be judged and recovered only by disassembling the fault coil in one time, and the qualified rate of the pouring coil is improved.

Description

technical field [0001] The invention relates to the detection of epoxy casting transformers, in particular to an iron core excitation device and a method for finding and repairing the breakdown range of casting coils. Background technique [0002] Epoxy resin is a high molecular polymer, and its curing process is an irreversible process that cannot be stopped artificially. During the curing process, a cross-linking polymerization reaction occurs to form a high polymer with a three-dimensional space network structure. This high polymer has strong, non-plastic, insoluble and infusible properties, and is a non-repairable reaction process. Once the casting coil is cured, it will form a molded solid with epoxy resin, filler, curing agent, reinforcing material, insulating material and electromagnetic wire as a whole, which determines its external shape and internal insulation distance, which can no longer be changed. Therefore, during the manufacturing process of epoxy casting tr...

AI Technical Summary

Problems solved by technology

When the insulation somewhere in the transformer coil is weak and cannot withstand the induction high-voltage test, the transformer coil will break down between layers, turns or tap leads, and the entire casting coil is considered irreparable and scrapped.

[0004] When it is necessary to find out the cause of the breakdown and find out the location of the breakdown, it is necessary to go through a series of processes, that is, remove the coil—handle the coil—reassemble the transformer—test the transformer—if it doesn’t work, remove the coil—reprocess the coil —Reassemble the transformer again—and test the transformer again. Repeating the process several times or more times is very cumbersome and the effect is not good. Not only can the cause of the breakdown be found, but the iron core of the transformer will be damaged after repeated disassembly and assembly.

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