JPH0354450B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a transposed structure of interleaved windings often used in transformer windings, particularly core type transformers.

[Technical background of the invention and its problems]

Various winding methods are selected for the windings used in core type transformers depending on the voltage and current of the windings, but interleaved windings have particularly good electrical characteristics against steep surge voltages. Due to its excellent properties, it is widely used in high voltage windings. Depending on the required current capacity, one or more rectangular conductors (conductors with a rectangular cross section) may be used in parallel as the conductor of the interleaved winding, or the space factor within the winding may be improved. For this purpose, as shown in Fig. 1, a plurality of rectangular conductors 1 with thin insulation 2 are put together, and then one or more electric wires with insulation 3 applied thereon (hereinafter referred to as composite wire) are assembled. Multiple units are used in parallel.

Fig. 2 shows the conductor arrangement of the interleaved winding 4 using a composite wire consisting of two rectangular conductors, and Fig. 3 is an enlarged sectional view of the winding section A in Fig. 2. The numbers in the figure indicate the winding numbers, and a and b indicate the two rectangular conductors in the composite wire. As is clear from FIG. 3, at the transition part (hereinafter referred to as a crossing) from one section 5 of the composite wire to another section 6, the rectangular conductor in the composite wire is located at its radial position on the outer diameter side of the winding. Replacement is performed. By exchanging the radial positions during crossing in this manner, the relative distances between each rectangular conductor and the opposing winding 7 can be equalized. By doing so, the mutual inductance between each rectangular conductor and the opposing windings can be made equal, and the current divisions in the rectangular conductors within the composite wire can be made equal. Here, the radial position of the rectangular conductor in the composite wire is swapped between sections with crossovers on the inner diameter side of the winding at the transition on the outer diameter side of the winding (hereinafter, this is especially referred to as high cell crossover). This part is used both for cutting the conductor necessary to obtain the interleaved winding and for cutting the conductor for radially exchanging the rectangular conductors in the composite wire.

However, the conventional interleaved winding method described above has the following problems. In other words, when there are two rectangular conductors in a composite wire, the transposition between the parallel conductors for the opposing windings is completely achieved by replacing the conductors in the radial direction at each high cell crossing as described above. When there are three rectangular conductors, the dislocation between the conductors becomes incomplete,
An unbalance occurs in the current shunt between the rectangular conductors, which increases the winding load loss and, in turn, increases the winding temperature. The reason why this current shunt is unbalanced will be explained below.

FIG. 4 shows the position of each rectangular conductor in the composite wire when an interleaved winding wire with three rectangular conductors in the composite wire and four turns per section is wound in the conventional winding method. In the figure, the radial position of each rectangular conductor is changed every time the rectangular conductor crosses over the high cell, and the mutual positions with respect to the opposing windings appear to be equal at first glance, but there are the following problems. In other words, flat conductors a and c occupy symmetrical positions every two sections, so the dislocation is perfect, but flat conductor b always occupies an intermediate position, which at first glance seems to mean that the arrangement of each conductor is averaged. However, there is a non-negligible difference in mutual inductance between the opposing windings. The current shunt to each rectangular conductor is determined by the impedance between each conductor and the opposing windings, so even if there is a slight difference in mutual inductance, if the resistance is the same, there will be no significant unbalance in the current shunt. In some cases, it may not occur. However, as the capacity of the transformer increases, the core becomes thicker, the number of turns decreases, and the resistance/inductance decreases, leading to an increase in unbalance. Current shunt imbalance increases load loss and increases winding temperature, resulting in problems such as deterioration of transformer characteristics.

[Purpose of the invention]

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide an improved transformer winding so that even when the number of rectangular conductors in a composite wire is three, current division is made equal.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention provides a structure in which a wire is connected between a first winding portion of a composite wire made of three conductors and a second winding portion of the composite wire to be wound next. In a transformer winding in which a plurality of sections are wound around an iron core leg by sandwiching the winding portion of the composite wire with a number of windings other than At least two transition portions are provided in which the positions in the winding radial direction are exchanged only between two adjacent conductors and the remaining one conductor. The transition between adjacent sections is approximately 1/3 from the beginning of the transformer winding.
It is provided in a section corresponding to approximately 2/3 of the area.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to the drawings.

Figure 5 shows the arrangement of each conductor in the interleaved transformer winding of the present invention, in which a new transition method is used at the high cell transition between the sections corresponding to 1/3 and 2/3 from the beginning of the winding. The transition between other sections is the same as the conventional high cell transition. That is, FIG. 5 illustratively shows three flat rectangular conductors a, b, and c in a composite wire, the number of turns in one section is four, and the number of sections is 16 (in order from the beginning of the winding, the first, second, . . . An interleaved winding with 16 sections (referred to as 16 sections) is shown, and from the beginning of the winding to the 4th section, the rectangular conductors a and c at both ends of the three rectangular conductors in the composite wire are connected at each high cell crossing. The rectangular conductor b is sandwiched between the rectangular conductors a and c, and high cell crossing is performed. Therefore, in the high cell crossing between the sections corresponding to 1/3 from the beginning of the winding (between the 5th section and the 6th section), 3 rectangular conductors a, b, and c
The radial position is swapped between the two adjacent flat conductors b and c and the remaining flat conductor a, and the radial position is swapped between the former two flat conductors b and c. will not be carried out. Furthermore, in the high cell crossing between the sections corresponding to 1/3, that is, between the sections corresponding to 2/3 from the beginning of the winding (between the 11th section and the 12th section), two of the three rectangular conductors b, c, and a are adjacent to each other. The radial positions are swapped between the main flat conductors c and a and the remaining flat conductor b, and the radial position is not swapped between the former two flat conductors c and a. In addition, in high cell crossings between sections other than the above, only the two rectangular conductors at both ends of the three rectangular conductors in the composite line are replaced, and the middle rectangular conductor is not replaced.

In this example, by configuring the high cell crossing of the rectangular conductors in the composite line between sections as described above, the rectangular conductor that was previously located in the middle of the three rectangular conductors in the composite line is moved to the end. , conversely, one of the rectangular conductors that was located at the end is now located in the middle. Therefore, by performing the above-mentioned new high cell crossing in the sections corresponding to 1/3 and 2/3 from the beginning of the winding, each rectangular conductor can occupy the middle position in each 1/3 of the winding. do. In other words, the rectangular conductors occupy equal positions over the entire length of the winding, ensuring complete transposition and correct current shunting.

In the above embodiment, the new high cell crossing is performed between sections corresponding to 1/3 and 2/3 from the start of winding, but these positions are approximately 1/3 and 2/3 as a rough guide. It is sufficient to do this, and it is clear that it is sufficient to make the new high cell crossing several times or all of them without worrying about the position, so that the positional relationship of each rectangular conductor is approximately equal as a whole. .

In addition, in the above embodiment, a new crossing method is adopted at the high cell transition section, but by adopting a new crossing method at the other transition sections, it is possible to interleave the current to each rectangular conductor in the composite wire to be equal. It is also clear that a double winding can be obtained.

Furthermore, in the case of a high-cell transition section where a new crossing method has not been adopted, the current can be shunted to each rectangular conductor in the composite wire in the same way as above without changing the radial position of each rectangular conductor in the composite wire. It is also clear that there will be equality.

〔Effect of the invention〕

According to the present invention, even when there are three rectangular conductors in a composite wire, it is possible to obtain a transformer winding in which the current branching of each rectangular conductor is equal. Therefore, it is possible to obtain a compact transformer winding with low loss and a small cooling device etc. transformers.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a conventional composite wire consisting of three rectangular conductors, Fig. 2 is a schematic vertical cross-sectional view of a conventional interleaved winding composed of a compound wire consisting of two rectangular conductors, and Fig. Fig. 2 is an enlarged explanatory diagram of the winding A section, Fig. 4 is a conductor arrangement diagram of a conventional transformer winding composed of a composite wire consisting of three rectangular conductors, and Fig. 5 is a diagram of the transformer winding of the present invention. It is a conductor arrangement diagram of a line. 1... Rectangular conductor, 2, 3... Insulator, 4... Interleaved winding, 5, 6... Winding section, 7... Opposed winding, 8... Iron core leg.

Claims (1)

[Claims] 1. Between the first winding portion of a composite wire consisting of three conductors and the second winding portion of the composite wire that is wound next, In a transformer winding in which a plurality of sections are wound around core legs with the winding portion of the composite wire sandwiched therebetween, adjacent sections of the three conductors in the composite wire are connected between adjacent sections. A transformer winding characterized in that at least two transition portions are provided in which the positions in the winding radial direction are exchanged only between two conductors and one remaining conductor. 2. The transformer winding according to claim 1, wherein the transition portions between adjacent sections are provided in sections corresponding to approximately 1/3 and approximately 2/3 from the winding start of the transformer winding.