Radial split cast-foil coil adapted to different connections and production method thereof

Abstract

The invention discloses a radial split cast-foil coil adapted to different connections and a production method thereof. The radial split cast-foil coil is characterized in that a low-voltage winding consists of four segments of foil windings (11, 12 and 21, 22) in cross arrangement and a heat dissipating air passage (4); each pair of two corresponding foil windings (11 and 12, or 21 and 22) is connected to form a respective radial split winding; a transition foil (2 or 3) is arranged between each of two pairs of correspondingly connected foil windings (11 and 12, and 21 and 22); four outlet heads (a1, x1, a2 and x2) of each phase of low-voltage winding are led out on the upper end parts, and the whole low-voltage winding is cast into a whole through vacuum casting. The production problemsof winding, casting, single-side four outlet heads, optimal cross transition of the same and different radial split windings of a low-voltage connection group and the like are solved, the impedance after splitting can be met and the resistance is completely balanced and symmetrical.

Description

technical field [0001] The invention relates to the manufacture of epoxy casting transformers, in particular to a radially split casting foil coil adapted to different connections and a manufacturing method thereof. Background technique [0002] In photovoltaic power generation, wind power generation, six-phase rectification and other occasions, a split transformer is required, and its low-voltage side winding is split into two windings that are not electrically connected, and operate separately. In the form of split windings, some use axial double splits (see figure 1 ), and some use low-pressure radial splitting (see figure 2 ). [0003] In order to make the technical indicators such as impedance and resistance after splitting tend to be balanced and symmetrical, the transformer with low-voltage radial splitting is usually in the following two structural forms. [0004] One is to use two sets of electromagnetic wires to be wound in parallel, which are two sets of coils...

AI Technical Summary

Problems solved by technology

However, there are serious deficiencies in the reference file. (1) The structure of the reference file should belong to the low-voltage radial split coil in terms of electrical performance (especially impedance voltage), but it contains axial segments in the radial split, but Unlike split and therefore not a true axial double-split coil

(2) Arranging the outlet ends at the upper and lower ends also has the technical problem that the winding is difficult to achieve epoxy resin pouring

(3) Same as the above two commonly used structural forms, the two split coils are carried out synchronously during winding, which can only be applied to the two split windings with equal turns, that is, the split windings of the same connection group cannot be applied to the split windings of different connection groups

(4) The two copper bars used for cross transition increase the radial size of the winding, making the thickness of the winding circumference uneven. For transformer windings with small capacity, it is necessary to occupy the space between the circumscribed circle of the iron core and the low-voltage coil. , for a transformer winding with a slightly larger capacity, or take the method of blocking at least three air passages inside the winding to place the two intersecting copper bars, which will reduce the heat dissipation surface area of ​​the entire low-voltage winding and increase the surface heat load , the temperature rises, even the temperature rise exceeds the specified limit, which is harmful to the normal operation of the transformer

(5) Due to the existence of copper discharge wire ends at the upper and lower ends, the transmission shaft of the winding machine is required to have a sufficient length during winding, so that it is limited to manufacture transformer windings with a slightly larger capacity, and only smaller capacity transformers can be manufactured. Winding, at the same time, it is inconvenient to fix the position at the beginning

It can be seen that it is difficult to implement the comparison file in terms of technology

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