JPH0322896Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a toroidal core transformer constructed by winding high and low voltage windings around a toroidal core.

BACKGROUND OF THE INVENTION Recently, it has been considered to use an amorphous alloy plate, which has less loss, as an iron core material for a transformer instead of a silicon steel plate. Amorphous alloy plates are extremely thin compared to silicon steel plates, and it is difficult to adopt the structure of conventional transformer cores as is. Therefore, various transformer structures suitable for using amorphous alloy plates have been proposed. . One method is to form the iron core into a ring shape (toroidal shape) and wind a large number of independent unit windings 201, 202, .
There is one in which the high voltage winding 2 is constructed by connecting a large number of unit windings in series.

In this type of transformer, when the tap is pulled out from the high-voltage winding, the tap is pulled out in accordance with the tap pull-out structure of a conventional transformer, as shown in FIG. 1 or 2. That is, in the configuration of FIG. 1, the unit winding groups 201 and 20 connected in series
2,... are connected to one external terminal L1, and taps 2a to 216 are connected to several (four in the example of FIG. 1) unit windings 213 to 216 located at the other end of the winding group. 2d is pulled out, and the terminal tap 2e is pulled out from the other end of the winding group, and a tap selector 3 for selecting the taps 2a to 2e is connected to the other external terminal L2. In addition, in the configuration shown in FIG. 2, the unit windings 201 to 216 are divided into two unit winding groups 2A and 2B, and mutually adjacent ends of both unit winding groups 2A and 2B are connected to external terminals L.
1 and L2, both unit winding groups 2A and 2B
Taps 2a to 2c and 2d to 2f are provided on some of the unit windings located on the other side of the adjacent unit windings, respectively, and predetermined taps of both unit winding groups are connected to each other by a connecting plate (not shown). ing.
By the way, when current flows through unit windings arranged in parallel at equal intervals, each unit winding has the same size as the adjacent unit windings on both sides of each unit winding. An electromagnetic force that attracts each other will act.

However, with the tap drawer structure as described above,
With the start end tap of the high voltage winding selected (in the example in Figure 1, tap 2a is selected, and the second
In the example shown in the figure, when the transformer is operated with taps 2a and 2f connected to each other, the idle coils are concentrated in one place in the circumferential direction of the annular core, so the current flows on both sides where the idle coils are formed. In the flowing unit windings, there is a large difference in the distance between the adjacent unit windings on one side and the adjacent unit windings on the other side, and these unit windings receive an electromagnetic force that is largely biased to one side. box office.
Therefore, it is inevitable that the electromagnetic mechanical force generated in the event of a short-circuit accident increases.

Purpose of the invention The purpose of the invention is to provide a ring core transformer that reduces the electromagnetic mechanical force in the event of a short circuit accident by dispersing the unit windings that become idle coils when the start end tap is selected.

Structure of the invention The present invention has a structure in which a high-voltage winding is provided in which a large number of independent unit windings are wound around a ring core and the many unit windings are connected in series, and a tap is drawn out from the high-voltage winding. This is an improved version of the ring core transformer.
In the present invention, the plurality of unit windings are divided into a plurality of unit winding groups, each of the taps is drawn out from the unit winding located on the end side of each unit winding group, and the tap to be selected is The groups are distributed and arranged at two or more different locations shifted in the circumferential direction of the annular core.

With the above configuration, the idle coils that occur when the start end tap of the high voltage winding is selected and operated are distributed in the circumferential direction of the annular core, so that the electromagnetic mechanical force acting on the winding in the event of a short circuit accident is reduced. can be reduced.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

Fig. 3 is a partially sectional perspective view of an example of an annular core transformer to which the present invention is applied. This is the annular core constructed. The annular core 1 includes a large number of winding frames 401,
402,... are installed at predetermined intervals in the circumferential direction, and each unit winding 2 is attached to each of these winding frames.
01, 202,... are wound, and the unit winding 20
1, 202, . . . constitute a high voltage winding 2. A low voltage coil 5 is wound along the annular core 1 so as to surround the unit windings 201, 202, . . . from the outside. Each turn of this low-voltage coil includes first and second radial conductors 501 and 502, which are arranged in the radial direction of the annular core 1 and substantially parallel to both end surfaces in the axial direction of the annular core 1; an outer longitudinal conductor 503 that is disposed on the outer circumferential side of the conductor 501 and connects the outer end of the first radial conductor 501 and the outer end of the second radial conductor 502;
02 and the inner end of the first radial conductor 501 of the adjacent turn.
It consists of 04. In this example, high voltage coil 2
After the first layer low voltage coil 5A is constructed so as to surround the outside of the annular iron core, a second layer low voltage coil 5A having a predetermined number of turns is further constructed so as to surround the outside of the first layer low voltage coil. 5B, an annular inter-winding insulation material 6 is provided between the high voltage coil 2 and the first layer low voltage coil 5A, and a first layer low voltage coil 5A is provided between the high voltage coil 2 and the first layer low voltage coil 5A.
A ring-shaped interlayer insulating material 7 is disposed between each of the coils A and the second-layer low-voltage coil 5B. An outlet conductor 8 is connected to the end of the low voltage coil 5.

In the present invention, the configuration of the low voltage coil is not limited to the above example; for example, a conventional winding conductor may be wound around a winding frame arranged to surround the high voltage coil 2 from the outside. The coil 5 may also be configured.

The present invention is an improved tap extraction structure from the high-voltage coil 2 in a ring core transformer having the above-described structure.The tap extraction structure in the present invention will be explained below with reference to FIGS. 4 to 8. do. In order to avoid cluttering the diagrams, only the high voltage coils are shown in Figures 4 to 8.
Illustration of the low voltage coil is omitted.

FIG. 4 shows the first embodiment of the present invention. In this embodiment, the unit windings 201, 202, ... constituting the high voltage coil 2 are each wound with the same number of turns, and these The unit winding is equally divided into a first unit winding group 2A and a second unit winding group 2B. One end of the unit winding 201 located at the starting end of the first unit winding group 2A is connected to the first external terminal L1.
Taps a, b and c are connected to the middle of the two unit windings 207 and 208 on the terminal end side of the first unit winding group 2A and from the end of the unit winding 208, respectively.
is being drawn out. Further, the tap d is pulled out from the end of the unit winding 209 located at the starting end of the second unit winding group 2B, and the two unit windings 215, located at the terminal end of the second unit winding group 2B, Taps p, q and r are drawn out from the middle of the unit winding 216 and from the end of the unit winding 216, respectively. A tap selector 10 for selecting taps p, q and r is provided and is connected to a second external terminal L2. The tap d provided at the starting end of the second unit winding group 2B is connected by the tap selector 11 to any of the taps a to c provided at the terminal end of the first unit winding group 2A. It's becoming like that.

If the taps of the first and second unit winding groups are arranged at different positions in the circumferential direction of the annular core 1 as described above, and the taps are selected at different positions in the circumferential direction of the annular core 1, Since the idle coils that occur when the transformer is operated with the start end tap of the main winding wire selected (tap a and d connected and tap p selected) are not concentrated in one place, A large electromagnetic force does not act between the windings located on both sides of the idle coil, and the electromagnetic force generated in the event of a short circuit accident can be reduced.

FIG. 5 shows a second embodiment of the present invention. In this embodiment, from the end and middle of one unit winding 201 located at the starting end of the first unit winding group 2A, Taps r and s are drawn out, and the tap selector 12 for selecting these taps is
is connected to external terminal L1. Taps a and b are pulled out from the middle of the unit winding 208 located at the terminal end of the first unit winding group 2A and from the end of the unit winding 208, respectively, and are connected to the starting end of the second unit winding group 2B. Taps c and d are drawn out from the end and the middle of one unit winding 209, respectively. 1 located at the terminal end of the second unit winding group 2B
Taps p and q are drawn out from the middle and end of each unit winding 216, respectively, and a tap selector 10 for selecting these taps is connected to the second external terminal L2. In this embodiment as well, idle coils generated when the transformer is operated with the start end tap of the high voltage winding selected (tap s and p are selected and taps a and d are connected) are Since they can be distributed in different directions, electromagnetic mechanical force can be reduced.

In each of the above embodiments, a large number of unit windings constituting the high voltage winding are divided into two, but it goes without saying that the high voltage winding can be divided into even more unit winding groups.

FIG. 6 shows a third embodiment of the present invention, in which 16 unit windings 201 to 216 are connected to a first unit winding consisting of four unit windings 201 to 204. Group 2A and 8 unit windings 20
a second unit winding group 2B consisting of 5 to 212;
It is divided into three unit winding groups 2C including unit windings 213 to 216. The end of the unit winding 201 located at the starting end of the first unit winding group 2A is connected to the first external terminal L1, and one unit winding 204 at the terminal end of the first unit winding group 2A Taps a and b are pulled out from the middle and end, respectively. Taps c and d are pulled out from the end and middle of one unit winding 205 located at the starting end of the second unit winding group 2B, respectively, and taps c and d are pulled out from the end and middle of one unit winding 205 located at the starting end of the second unit winding group 2B. one unit winding 212
Taps p and q are pulled out from the middle and end, respectively. Further, taps r and s are drawn out from the middle and end of one unit winding 213 located at the starting end of the third unit winding group 2C, respectively, and the taps r and s are drawn out from the middle and end of one unit winding 213 located at the starting end of the third unit winding group 2C, and the unit located at the terminal end of the third unit winding group 2C. Winding wire 21
6 is connected to the second external terminal L2. A tap selector (not shown) is provided for each of the tap groups a to d and p to s, and when the transformer is in operation, either tap a or b is connected to either tap c or d. At the same time, either tap p or q is connected to either tap r or s.

FIG. 7 shows a fourth embodiment of the present invention, in which unit windings 201 to 216
is divided into first and second unit winding groups 2A and 2B, one unit winding 201 located at the starting end of the first unit winding group 2A and two unit windings 207 located at the terminal end. and 208 are other unit windings 20
The unit winding 201 has a smaller number of turns than the unit windings 2 to 206, and the end of the unit winding 201 is connected to the first external terminal L1. Also, the connection point between unit windings 206 and 207,
Connection point between unit windings 207 and 208 and unit winding 2
Taps a, b and c are drawn out from the ends of 08, respectively. Further, the number of turns of the unit winding 209 located at the starting end of the second unit winding group 2B and the two unit windings 215 and 216 located at the end are set to be smaller than the number of turns of the other unit windings 210 to 214. , the end of the unit winding 209 on the starting end side is tap a
It is connected to a tap selector 13 that selects from c to c. Connection point between unit windings 214 and 215 on the terminal end side of second unit winding group 2B, unit windings 215 and 2
Taps p, q and r are drawn out from the 16 connection points and the end of the unit winding 216, respectively, and a tap selector 10 for selecting these taps is connected to the second external terminal L2.

FIG. 8 shows a fifth embodiment of the present invention, and in this embodiment, the manner of winding and division of the unit winding group is the same as in the embodiment of FIG. 7.
In the embodiment of FIG. 8, the first unit winding group 2
Two unit windings 207 and 208 on the terminal side of A
constitutes one tap of winding, and the unit winding is 20
Taps a and b are drawn out from the connection point of 6 and 207 and the end of the unit winding 208, respectively. Other points are similar to the embodiment shown in FIG.

As in the embodiments shown in FIGS. 7 and 8 above, if the number of turns of the unit winding located at the end of each unit winding group is made smaller than the number of turns of the other unit windings,
Since the voltage applied to the winding ends can be lowered, there is no need to reinforce the insulation at the winding ends.
The structure of the transformer can be simplified.

Also, as in the embodiments shown in FIGS. 7 and 8 above,
1 without pulling out the tap from the middle of the unit winding.
If one or more unit windings constitute one tap winding, the tap can be easily drawn out.

In each of the above embodiments, the high-voltage winding was configured with 16 unit windings, but the number of unit windings is arbitrary, and the number of unit winding groups into which these unit windings are divided is arbitrary. It is.

Effects of the invention As described above, according to the invention, the idle coils that occur when the start end tap of the high voltage winding is selected and operated are distributed in the circumferential direction of the ring core, so that the winding can be wound in the event of a short circuit accident. The electromagnetic mechanical force acting on the line can be reduced, and a highly reliable transformer that is resistant to short circuit accidents can be provided.

[Brief explanation of the drawing]

Figures 1 and 2 are winding configuration diagrams showing a tap pull-out structure when the tap is pulled out from the high-voltage winding of a circular core transformer in accordance with the tap pull-out structure of a conventional transformer. A partially sectional perspective view of the outer appearance of the ring core transformer to which the present invention is applied, and Figures 4 to 8 are winding configurations showing the configurations of high-voltage windings in different embodiments of the present invention, respectively. It is a diagram. 1... Annular iron core, 2... High voltage winding, 2A, 2
B, 2C... Unit winding group, 201-216... Unit winding, a-d, p-s... Tap.

Claims (1)

[Claims for Utility Model Registration] (1) A high-voltage winding configured by winding a large number of independent unit windings around an annular core and connecting the large number of unit windings in series; In a toroidal core transformer in which taps are drawn out from a wire, the plurality of unit windings are divided into a plurality of unit winding groups, and each tap is connected to at least one coil located on the end side of each unit winding group. A toroidal core transformer characterized in that tap groups to be drawn out from a unit winding and to be selected are distributed and arranged at two or more different locations shifted in the circumferential direction of the toroidal core. (2) Utility model registration claim 1, characterized in that each of the plurality of unit windings is individually wound around a plurality of winding frames arranged in a circumferential direction of the annular core. The ring core transformer described in . (3) The toroidal core transformer according to claim 1 or 2 of the utility model registration claim, characterized in that one tap of winding consists of one unit winding. (4) The annular core transformer according to any one of claims 1 to 3, wherein the annular core is made of a wound body of an amorphous alloy plate. (5) Any one of claims 1 to 4 of the utility model registration claim, characterized in that the unit winding located at the end of each of the unit windings has a smaller number of turns than the other unit windings. An annular core transformer according to one of the above.