JPH0286107A - Three-phase on-load tap-changing transformer - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a three-phase on-load tap-changing transformer having a triangularly connected high-voltage winding.

[Prior Art] As shown in Japanese Unexamined Patent Publication No. 54-93418, as a general three-phase transformer, tap switching on the high voltage side is performed by a non-voltage tap changer placed above the iron core, and the high voltage winding It is known that the wires are connected in a triangular manner.

On the other hand, a three-phase on-load tap changer transformer is known in which the taps of triangularly connected high-voltage windings are switched by an on-load tap changer.

This three-phase on-load tap-changing transformer has a low-voltage winding on each core leg of a tripod core, a high-voltage winding of each phase wound in the same direction around the outer periphery of this low-voltage winding, and windings between the legs of the tripod core. A one-phase on-load tap changer and a two-phase on-load tap changer were placed in the section.

In addition, a three-phase high-voltage bushing was attached to the side wall of the transformer outer box that housed these, corresponding to the side of the tripod core, and the high-voltage windings of each phase were connected in a triangular manner, and connected to the high-voltage bushing by a line lead wire. .

[Problems to be Solved by the Invention] Since the conventional three-phase on-load tap change transformer was configured as described above, no consideration was given to simplifying the routing of the line lead wires. After deciding on the basic configuration, the line lead wires are routed using the remaining parts, which may involve going around the on-load tap changer, which makes the route complicated and long, and it is necessary to maintain insulation. The whole thing had become larger.

An object of the present invention is to provide a three-phase on-load tap change transformer that can simplify and shorten the routing of line lead wires.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a one-phase load tap changer and a two-phase load tap changer between the legs of a tripod core, approximately parallel to the three-phase core. A tap changer is arranged respectively, and among the high voltage windings of each phase wound around each core leg of the tripod core, one of the high voltage windings located on both sides is used to switch the tap at the time of load for the above single phase. It is characterized in that the high voltage winding on which the device is placed is reversely wound with respect to the other high voltage windings.

[Function] By configuring the three-phase on-load tap changer according to the present invention as described above, line lead wires can be drawn by utilizing the remaining space below the one-phase and two-phase on-load tap changers. Even when the windings are rotated, sufficient insulation from other parts can be ensured, compared to when high voltage windings other than the designated high voltage windings are wound in the opposite direction, or when all high voltage windings are wound in the same direction. As a result, the line lead wire leading to the high-voltage bushing can be routed easily and shortened, and an overall compact three-phase on-load tap change transformer can be obtained.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 are a vertical cross-sectional front view and a cross-sectional plan view of a three-phase on-load tap-changing transformer according to an embodiment of the present invention.

Inside the transformer outer box 14 are each core leg 2.3 of the tripod core 1.
Each phase high-voltage winding 5, 6.7 consists of a low-voltage winding (not shown in 4), a high-voltage winding wound around the outer periphery of the low-voltage winding, and a high-voltage tap winding.
is provided, and approximately parallel to each phase core leg 2°3.4, and in the portion between each phase core leg 2, 3.4, a two-phase and one-phase on-load tap changer 8, 9 is supported from above the transformer outer box 14. The high-voltage winding 7 on either side of the core legs 2, 4 on both sides of each phase core leg 2, 3.4, and on which the one-phase on-load tap changer 9 is arranged, is connected to the other high-voltage winding. The wires 5 and 6 are wound in the opposite direction, and the high voltage winding 5
, 6 are wound in the same direction so that the high-voltage tap windings (not shown) are electrically located on the same line terminal side. In addition, on the side wall of the transformer outer box 14 parallel to each phase core leg 2, 3.4,
A three-phase high-pressure bushing 13 is provided, and each phase is high-pressure! 5,
6.7 and the on-load tap changers 8 and 9 are triangularly connected as shown in FIG. 5, and line lead wires 10, 11 and 12 leading to the high pressure bushing 13 are used.

Note that there is no particular change on the low pressure side, so a description thereof will be omitted.

3 and 4 are a schematic front view and a plan view showing the arrangement of the high-voltage windings 5, 6.7 of each phase and the routing state of each lead wire, etc. in FIGS. 1 and 2, and FIG. 5 is a wiring diagram thereof.

As can be seen from each of these times, the high voltage winding 7 is reversely wound with respect to the other high voltage windings 5 and 6, and its terminal U rises upward on the side of the high voltage winding 7, and the high voltage winding 1iA
Connect to the winding end terminal Z of No. 5 to connect the on-load tap changer 8,
It is connected to the U-phase high-pressure bushing by a line lead wire 11 routed through the remaining space below 9. In addition, the winding end X of the high voltage winding 7 is connected to a one-phase on-load tap changer 9.
It is connected to the. On the other hand, the high-voltage winding 6 wound around the central core leg 3 has its terminal ■ connected to the V-phase high-voltage bushing via the line lead wire 12, and is also connected to the on-load tap changer 9 at -Soma. The winding end Y is connected to a two-phase on-load tap changer 8. Further, the high voltage winding 5 wound around the iron core leg 2 has its terminal W connected to a two-phase on-load tap changer 8, and its winding end Z connected to a line lead wire 11. In this way the fifth
The configuration is based on the wiring diagram shown in the figure.

As mentioned above, the line lead wires 10 and 12 that connect to the V-phase and W-phase high-pressure bushings are extremely short.
On the other hand, the U-phase line lead wire 11, which is relatively long, can be routed almost horizontally through the space formed at the bottom of the load tap changers 8 and 9 and connected to the terminal U. There is no need to go around the 8°9, and there is no adverse effect on electrical insulation with other parts. Furthermore, as can be seen from FIG. 2 in particular, sufficient insulation can also be maintained between the line lead wire 11 and the lead wire 15 that connects the on-load tap changer 9 and the high-voltage winding 7.

In this respect, the eighth
This figure can be better understood by comparing it with the three-phase on-load tap-changing transformer shown in FIG.

In particular, as shown in FIG. 10, the high-voltage winding 6 wound around the central core leg 3 is reversely wound with respect to the other high-voltage windings 5 and 7. It is different from the embodiment of the invention. Therefore, when wiring is performed based on the wiring diagram shown in FIG. 5, the line lead wire 12 connecting between the terminal V of the high voltage winding 6 and the high voltage bushing of the phase ■ is connected as shown in FIGS. 8 and 10. The line lead wire 12 passes vertically between the on-load tap changers 8 and 9, compared to the case shown in FIG.
This increases the length of the structure, and also affects the electrical insulation in the vicinity, leading to an increase in the overall size.

6 and 7 are a vertical sectional front view and a horizontal sectional plan view showing a three-phase on-load tap switching transformer according to another embodiment of the present invention.

This embodiment differs from the previous embodiment in that a three-phase high-voltage bushing 13 is provided on the side wall opposite to the side of the tripod core in the transformer outer box 14, and the other configurations are the same, so they are equivalent. are given the same reference numerals and detailed explanations will be omitted.

Compared to the configuration shown in FIGS. 1 and 2, the line lead wire 10 is
, 11, 12 increases, and the routing becomes somewhat complicated, but the line lead wires 10, 11, . 12 has been shortened in overall length and is easier to route. In other words, in this embodiment, the high-voltage winding 7 is wound around one of the core legs 2 and 4 located on both sides of each phase core leg, and the high-voltage winding 7 is wound around one of the core legs 2 and 4 located on both sides of each phase core leg, and the one phase load tap changer 9 is disposed. is reversely wound with respect to the other high voltage windings 5°6, so the high voltage winding 7 is connected to the other high voltage windings 5,
Among the line lead wires 10, 11, and 12, the axial length of the line lead wire 11 in particular can be shortened compared to the case where the winding direction is the same as that of the line lead wire 6 or the case where other high voltage windings are wound in the opposite direction.

Moreover, the line lead wires 11 and 12 connected to the U-phase and V-phase high-pressure bushings 13 can be routed almost horizontally by utilizing the remaining space formed at the bottom of the WJ load tap changers 8 and 9. Therefore, there is no adverse effect on electrical insulation of other parts.

[Effects of the Invention] As explained above, the present invention provides a high-voltage winding wound on either side of each phase core leg of the high voltage winding wound around each phase core leg of a tripod core; The winding direction of the high-voltage winding on which the on-load tap changer is installed is reversed from that of the other high-voltage windings, making it easy to connect the line lead wire by utilizing the remaining time below the on-load tap changer. A three-phase on-load tap change transformer that can be routed and has a shortened axial length is obtained.

[Brief explanation of drawings]

FIGS. 1 and 2 are a vertical cross-sectional front view and a cross-sectional plan view of a three-phase on-load tap-changing transformer according to an embodiment of the present invention, and FIGS. 3 and 4 are similar to FIGS. 1 and 2. A schematic front view and a plan view showing the routing state of each phase high voltage winding and each lead wire, FIG. 5 is a wiring diagram of FIG. 1, and FIGS. 6 and 7 are according to other embodiments of the present invention. A vertical cross-sectional front view and a cross-sectional plan view of a three-phase on-load tap-changing transformer, and FIGS. 8 and 9 are vertical cross-sectional front views of a three-phase on-load tap-changing transformer proposed for comparison with the present invention. and cross-sectional plan view,
10 and 11 are a schematic front view and a plan view showing the routing state of each phase high-voltage winding and each lead wire in FIGS. 8 and 9. FIG. 1... Tripod core, 2, 3, 4... Core legs, 5°6.7... Each phase high voltage winding, 8, 9...
...Tap changer on load, 10, 11, 12...
... Line lead wire, 13 ... High voltage bushing, 14 ... Transformer outer box. Figure 3 Figure 4 Figure 1 Figure 5 Figure 1 Figure 5.6.7: High voltage enlightenment 8.9: Negative "dark time tη$ vessel to, t/, /2 Ni line node training 14: * Circumstances figOutsideFigure 2Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11

Claims (3)

[Claims] 1. A high-voltage winding of each phase is wound around each core leg of the tripod core stored in the transformer outer box, and a one-phase on-load tap changer is installed between the legs of each core leg approximately parallel to the tripod core. A three-phase load is provided with a two-phase on-load tap changer, the high-voltage windings of each phase are triangularly connected, and connected via line lead wires to the three-phase high-voltage bushing provided in the transformer outer box. In the time tap changeover transformer, the high voltage winding is wound around the iron core legs located on both sides of the tripod core, and the one on which the load tap changer for one phase is arranged;
A three-phase load tap changeover transformer characterized in that the above-mentioned high voltage winding is reversely wound. 2. 2. A three-phase on-load tap-change transformer according to claim 1, wherein said high-voltage bushing is provided on a side wall of said transformer outer box substantially parallel to said tripod core. 3. In the device according to claim 1, the double-load tap changer is supported from above the outer box of the transformer, and the high-voltage winding wound in the opposite direction with respect to the other high-voltage winding has the line side terminal at the bottom. A three-phase on-load tap-changing transformer characterized by the following: