JPS6241405B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a winding used in an induction appliance such as a transformer or a reactor, and particularly to a helical winding in which transposition can be effectively performed.

Especially in windings for large-capacity induction appliances, if the effective cross-sectional area of the conductor in the direction perpendicular to the leakage magnetic flux is large, eddy currents will be induced due to the difference in the number of flux linkages on both sides of one conductor. There is a loss due to this. Therefore, the conductor consists of a plurality of mutually insulated strands, which are used in parallel. Since the number of turns is small in the low-voltage side winding of a transformer, a helical winding in which multiple strands of wire are arranged in the radial direction of the winding and wound in a spiral is arranged in two stages on the inside and outside. These helical windings were connected in series. However, in a winding in which a large number of strands are wound in parallel, each strand does not interlink with the magnetic flux in a balanced manner, so that a circulating current flows between the strands, increasing loss. Therefore, each strand is usually transposed appropriately to average the number of magnetic flux linkages of each strand.

1 to 3 are diagrams for explaining the dislocation state of a conventional helical winding. In this example, seven strands (strand 1 to strand 7) are arranged in the radial direction of the winding, and are spirally wound to form an inner helical winding 8 and an outer helical winding 9. The helical windings 8 and 9 are arranged in two stages and connected in series. In the helical windings 8 and 9 of each stage, the dislocations of the strands occur at the dislocation locations corresponding to the number of strands minus 1 (in this example, there are 6 dislocation locations since 7 strands are used). It is done.

Figure 1 shows the transposition order of the wires in the inner helical winding 8. As shown in Figure A, at the beginning of winding, the wire 1 is placed at the innermost circumference, and then radially outward. The strands 2 to 7 are arranged in sequence, with the strand 7 being at the outermost periphery. In the first dislocation, as shown in FIG. , the wire 6 is located at the outermost periphery. FIG. 3 is a perspective view showing the transferred state of the strands 7 in the first dislocation. In the second dislocation, as shown in FIG. The strands 5 are at the outermost periphery. By sequentially transferring the strands on the outermost periphery to the outermost periphery in this way, the third dislocation [D], the fourth dislocation [E], and the fifth dislocation [FIG. ], the sixth dislocation [see figure G] is carried out. The arrows in FIG. 1 indicate the direction of transfer of the strands. Incidentally, in the outer helical winding 9 as well, the respective strands 1 to 7 are similarly transposed in sequence.

FIG. 2 is a connection diagram of the inner helical winding 8 and the outer helical winding 9, both of which are connected in series. And for inner helical winding 8 it is 10A~10
Six dislocations from the first to the sixth at the position indicated by F are 10G to 10 in the outer helical winding 9.
Six dislocations from the 7th to the 12th are performed at the positions indicated by F. Note that 1 in the diagram
1 indicates the iron core, x indicates the starting end of the winding, and u indicates the ending end of the winding.

FIG. 4 is a winding layout diagram of a transformer using this helical winding. The helical windings 8 and 9 are used as a low voltage winding 12, and a high voltage winding 13 is arranged outside the low voltage winding 12. X and U in the figure are the winding start end and winding end of the high voltage winding 13.

In this conventional transposition method, the transferred strand protrudes by the width of the strand, as shown in FIG. Since electric field concentration occurs between the projecting portion and the opposing electrode of the high voltage winding, reinforcing insulation is required at the transfer portion of each strand. Furthermore, since the dislocation points are evenly distributed throughout the winding, some of the dislocation points appear opposite to the line end, which is the maximum potential of the high voltage winding. The composite electric field E of the transferred wire at, for example, the ninth dislocation point of the outer helical winding (the position indicated by reference numeral 10I in FIG. 2), which is close to the line end, is determined by the following formula.

E=K√ _a2 + _r2 where K is the electric field concentration coefficient, E _a is the axial electric field, and E _r is the radial electric field. In this way, electric field concentration may occur when the dislocation point of the strands faces the line end on the high-voltage winding side, so the gap d between the low-voltage winding 12 and the high-voltage winding 13 shown in FIG. This poses a problem in the miniaturization of induction electric appliances. In addition, in the conventional method, the work of spirally winding the strands and the work of transferring the strands are repeated, and this repetition increases as the number of strands increases, resulting in very poor work efficiency. It has various drawbacks.

SUMMARY OF THE INVENTION An object of the present invention is to provide a helical winding for an induction electric appliance that eliminates the drawbacks of the prior art, is electrically stable without electric field concentration, and is easy to assemble.

In order to achieve this object, the present invention arranges a helical winding in which a plurality of wires are arranged in the radial direction of the winding and wound spirally in two stages inside and outside,
In the case where these helical windings are connected in series, the outer helical winding is located at 1/3n turn position from the connection point side with the inner helical winding, where n is the total number of turns of the outer helical winding. It is characterized in that a transition space extending long toward the winding axis is provided nearby, and the strands are sequentially transferred along the winding axis within the transition space.

As shown in FIG. 5, in a two-stage winding including an inner helical winding 8 and an outer helical winding 9, the leakage magnetic flux of the inner helical winding 8 corresponding to the first stage is equal to the total leakage magnetic flux Φ. 1/4, the leakage magnetic flux of the outer helical winding 9 corresponding to the second stage is 3/4 of the total leakage magnetic flux.
be. Therefore, in order to equalize the flux linkage of the entire winding, It is sufficient to transpose at a position where . In other words, if the height of the helical winding is h, then 1/3 h from the connection point side of the outer helical winding 9 with the inner helical winding 8.
If the dislocation occurs near the position of , the interlinkage flux of the entire winding can be made uniform. In the case of FIG. 5, the dislocation position was explained based on the height h of the winding, but it can be specified by the number of turns of the winding. That is, when the total number of turns of the outer helical winding 9 is n,
The position near the 1/3n turn from the connection point side with the inner helical winding 8 is the transposition position.

As shown in FIG. 6, a dislocation space 14 extending in the winding axis direction is provided at this dislocation position, and this dislocation space 1
4, the strands 1 to 7 are sequentially transposed at once. 7th
The figure shows this dislocation state, and the arrows indicate each strand 1
~7 dislocation directions are shown, respectively. 15 to 19 in Figure 6 indicate the strand units, and this strand unit
15 to 19 are composed of wires arranged in parallel.

FIG. 8 is a wire current distribution diagram of each winding. In addition, for each winding, seven strands of wire were arranged in the radial direction of the winding and wound spirally, and the helical winding was arranged in two stages on the inside and outside, and both helical windings were connected in series. It is something. In the figure, the curve drawn with a two-dot chain line is a winding that has no dislocation at all, and the curve drawn with a broken line is a winding that has been evenly transposed using the conventional method described above.
The curve drawn with a solid line is a characteristic curve of the winding wire of the present invention. In addition, the straight line drawn with a dashed-dotted line in the figure indicates the average current of the strands. As is clear from this figure, the winding according to the present invention has a more uniform distribution of strand current than the conventional winding.

As explained above, according to the present invention, the transposition occurs at one location near the position where the flux linkage of the entire winding becomes uniform, so the transposition can occur at a location away from the line end of the high-voltage winding, making it electrically more efficient. It is stable, and the gap with the high voltage winding can be made narrower than before. In addition, since a dislocation space is created and dislocation takes place within the space, the strands do not protrude outward, reducing electric field concentration and eliminating the need for reinforcing insulation.Furthermore, since the dislocation takes place all at once, work efficiency is greatly improved. can be achieved.

[Brief explanation of the drawing]

Figures 1 to 3 are arrangement diagrams for explaining the arrangement of strands due to transposition in conventional windings, Figure 2 is a connection diagram with the transposition positions of the winding, and Figure 3 is the winding. A perspective view showing the transfer state of the strands in the wire, Fig. 4 is a winding arrangement diagram of a transformer using the winding, and Fig. 5 shows the transposition position and leakage magnetic flux ratio of the winding of the present invention. Explanatory drawings, FIG. 6 is a side view showing the dislocation state of the winding, FIG. Arrangement diagram showing the arrangement state of the strands as seen on the line,
FIG. 8 is a strand current distribution diagram of each winding. 1 to 7...Element wire, 8...Inner helical winding, 9
...outer helical winding, 14...dislocation space.

Claims (1)

[Claims] 1 A helical winding in which a plurality of wires are arranged in the radial direction of the winding and wound spirally is arranged in two stages on the inside and outside, and these helical windings are connected in series, In an outer helical winding, and when the total number of turns of the outer helical winding is n, a transition that extends long toward the winding axis near the 1/3n turn position from the connection point side with the inner helical winding. A helical winding wire for an induction electric appliance, characterized in that a space is provided, and the strands are sequentially transferred along the winding axis direction within the transition space.