Ultracrystalline transformer core manufacturing method and special mould therefor

Abstract

The invention relates to an ultracrystalline transformer core manufacturing method and a special mould therefor. The method comprises that: ultracrystalline laminar strips are overlapped and wound on a circular mould to form a circular blank, an internal mould of a square mould is inserted into a circular inner window of a circular core blank to make the inner window deformed into the square window, and a square external mould encloses and clamps on the outside of the core to form a square core blank; the square core blank and the square mould are put into a high frequency heating furnace together, subjected to heat treatment for four hours at a temperature of between 550 and 570 DEG C and temperature reduction at a rate of between 95 and 105 DEG C per minute to 80 DEG C, and injected with modified epoxy resin containing firming agent, and then put into an oven for curing and sizing for 8 hours at a temperature of between 80 and 110+ / -5 DEG C; and the square core blank and the square mould are taken out for demoulding, naturally cooled, and divided into two U-shaped ultracrystalline transformer cores. The method and the special mould adopted make the ultracrystalline strips or blanks stressed evenly in various processes such as winding, heat treatment and the like and avoid breakage and damage. The core has good electromagnetic characteristic and frequency characteristic, and low power consumption and temperature rise, and can be made into transformer cores for a high-power high-frequency high-voltage power supply.

Description

technical field [0001] The invention relates to a manufacturing method of an ultramicrocrystalline transformer iron core and a special mold for the method. technical background [0002] The transformer core is the magnetic conductive element inside the power transformer. Silicon steel sheet and ferrite are the most common materials for making the transformer core. With the development of science and technology, many large-scale equipment (such as the flue gas electrostatic precipitator of large boilers, etc.) need to use high-power high-frequency high-voltage power supply, which puts forward higher requirements for the power and power consumption of the transformer core in the high-frequency state . The power consumption of the iron core causes the temperature rise of the transformer. Controlling the power consumption of the transformer core, especially the transformer core of high-power high-frequency high-voltage power supply, is an important link to reduce the temperatur...

AI Technical Summary

Problems solved by technology

[0004] 1. Due to the brittleness (fragility) of the ultra-microcrystalline thin sheet strip, and the thin sheet-like strip itself is thick on one side and thin on the other side, it is easy to produce stress unevenness when winding a single-layer strip directly on a square mold. Fracture, and the thickness of the ultra-microcrystalline iron core body formed by winding is uneven; the demoulding body is also prone to cracking and deformation in the process of heat treatment and shaping, so the yield is low

[0005] 2. If the furnace temperature control range of heat treatment is too large, the uneven temperature of each point in the furnace will reduce the magnetic permeability of the iron core, the working temperature rise of the iron core will be too high, the power loss will be too large, and it will affect the mechanical strength and magnetic permeability. Because high-power transformers have higher requirements on working temperature rise, power loss, mechanical strength, magnetic permeability and other indicators, the current conventional technology is generally limited to the production of ultra-microcrystalline iron cores for transformers with lower power

For example, the power loss of the high-power high-frequency transformer core used in the electrostatic precipitator must be controlled at less than 35W / kg, but the ultrafine crystal core made by the existing technology is difficult to meet this requirement

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