JPS615510A - Structure of transformer winding - Google Patents

Abstract

PURPOSE:To miniaturize the titled structure by reducing the main insulation disttance between windings by a method wherein the opposed part to the tertiary winding in the neighborhood of the medium-tension line of a shunt winding, the opposed part to a series winding in the neighborhood of the high-tension line terminal of the shunt winding, and the opposed part to the series winding in the neighborhood of the medium neutral point terminal of the shunt winding are each provided with an insulator. CONSTITUTION:The tertiary winding 2, shunt winding 3, and series winding 4 are arranged outside an iron core 1. With respect to the shunt winding 3, an insulator 5 is as conventional loaded to the opposed part to the series winding 4 located at the center in the axial direction, i.e. in the neighborhood of a high-tension line terminal U, and an insulator 6 is loaded in a space formed by reducing the number of turns of the conductor in the opposed part to the tertiary winding 2 in the neighborhood of the medium- tension line terminal (u); further, an insulator 7 is loaded in a space formed by reducing the number of turns of the winding conductor in the opposed part to the series winding 4 in the neighborhood of the medium neutral point terminal Q. With respect to the series winding 4, an insulator 8 is loaded in a space formed by reducing the number of turns of the winding conductor located in the opposite part to the shunt winding 3 in the neighborhood of the high-tension line terminal U.

Description

Detailed Description of the Invention [Field of Application of the Invention] The present invention relates to a transformer winding structure, particularly a transformer winding structure suitable for an autotransformer having a tertiary winding, a shunt winding and a series winding. Regarding.

[Background of the invention]

In general, ultra-high voltage and ultra-super high voltage transformers have a winding structure in which a tertiary winding 2, a shunt 4 winding 3, and a series winding 4 are arranged concentrically on the outside of an iron core 1, as shown in FIG. A medium voltage line terminal U and a medium voltage neutral point terminal Q are connected from both ends of the shunt winding 3, and the medium voltage line terminal U is electrically connected to the upper and lower terminals of the series winding 4. A high voltage line terminal U is drawn out from the axial center of the series winding 4.

FIG. 3 shows an example of the potential distribution within the winding during a commercial frequency test in such an autotransformer.

In the figure, vo is the potential of the high-voltage line terminal U, vI is the potential of the medium-voltage line terminal U, and 3 is the potential of the low-voltage line terminal a.

As shown in FIG. 2, if the main insulation distance between the tertiary winding 2 and the shunt winding 3 is 61, and the main insulation distance between the shunt winding 3 and the series winding 4 is t2, then Main insulation distance t1 in insulation design
is determined from the constraint surface of the zero slope EI near the medium voltage line terminal U, and the main insulation distance t! is determined based on the control of the potential gradient E2 near the high voltage line terminal U. Here, El
m and Ez become, and the dimensions between each winding are determined in this way.

In order to reduce the dimensions between each winding, for example,
According to the method introduced in Publication No. 13015, as shown in FIG. , an insulator 5 for adjusting the winding width is arranged, thereby reducing the main insulation distance t2 and achieving miniaturization. However, as the capacity of each winding wire becomes larger, this winding structure exceeds the limit for rail transport.

[Purpose of the invention]

An object of the present invention is to provide a compact transformer winding structure by reducing the main insulation distance between windings.

[Summary of the Invention] The present invention provides a portion of a shunt winding facing a tertiary winding near a medium voltage line, a portion of the shunt winding facing a series winding near a high voltage line terminal, and a portion of a shunt winding facing a tertiary winding near a high voltage line terminal; The main insulation distance is reduced by providing an insulator in each of the tonneaus facing the series winding near the medium-voltage neutral point terminal of the line, and suppressing an increase in the potential gradient of the winding with this insulator. .

[Embodiments of the invention]

The present invention will be explained below with reference to an embodiment shown in FIG.

A tertiary winding 2, a shunt winding 3, and a series winding 4 are arranged outside the iron core 1. Looking at shunt winding 3,
An insulator 5 is attached to the central part of the shaft in the axial direction, a part facing the series winding 4 near the high-voltage line terminal U of the claw 9, as in the past, and a tertiary winding 2 near the medium-voltage line terminal U. An insulator 6 is installed in the space formed by reducing the number of turns of the conductor, and a winding is installed in the area facing the series winding 4 near the medium-voltage neutral terminal Q. Reduce the number of turns of the conductor
An insulator 7 is installed in the space formed at the center.

Further, regarding the series winding 4, an insulator 8 is installed in a space formed by reducing the number of turns of the winding conductor at a portion facing the shunt winding 3 near the high-voltage line terminal U.

With this configuration, the potential gradient E1 of the main insulation between the tertiary winding 2 and the shunt winding 3 is as follows, when the thickness of the insulator 6 is δ, which is the same potential gradient El as in the conventional case. Under , the main insulation distance t! depends on the thickness δ2 of the insulator 6. can be reduced.

Further, the potential gradient E2 of the main insulation near the high-voltage line terminal U between the shunt winding 3 and the series winding 4 is determined by the thickness of the insulator 5.8 as δ1. If δ4, then, depending on the thickness δ4 of the insulator 8 in addition to the insulator 5, the potential gradient E is the same as the conventional one.
Main insulation distance t! can be reduced.

In addition, the main insulation potential gradient E3 near the medium voltage neutral point terminal Q is:
If the thickness of the insulator 7 is δ3, then 9, the potential gradient E3
is the thickness δ of the insulator 7 which increases with the reduction of the main insulation distance t2.
3, it can be adjusted to a value lower than the potential gradient E2.

In this way, by appropriately adjusting the thickness of each insulator, it is possible to make the potential gradient approximately equal along the axial direction of the winding, thereby reducing the main insulation dimension tl t tl. .

In the above embodiment, the insulator 8 was also provided in the series winding 4, but
The same effect can be obtained even if the insulator 8 is omitted by adjusting the thickness δ1 of the insulator 5 of the shunt winding 3.

〔Effect of the invention〕

As explained above, the present invention provides a shunt winding in the portion of the shunt winding 3 that faces the tertiary winding 2 near the medium-voltage line terminal U, and the portion of the shunt winding that faces the series winding 4 near the high-voltage line terminal U. In the opposite part between the wire and the series winding 4 near the intermediate voltage neutral point terminal Q of the shunt winding 3,
Since each insulator is provided, the potential gradient of each part is corrected and the main insulation distance is reduced, resulting in a compact transformer winding structure.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a transformer winding structure according to an embodiment of the present invention, FIG. 2 is a sectional view of a conventional transformer winding structure, and FIG. 3 is a sectional view of the structure shown in FIG. 2 during a commercial frequency test. It is a potential distribution diagram within a winding. 1... Iron core, 2... Tertiary winding, 3... Shunt winding,
4...Series winding, 5-8...Insulator, U...Medium voltage line terminal, Q...Medium neutral point terminal, U...High voltage line terminal.

Claims (1)

[Claims] 1. A tertiary winding, a shunt winding, and a series winding are arranged in this order around the outer circumference of the iron core, and the shunt winding has a medium voltage line terminal and a medium voltage neutral point terminal at both ends, and the above The series winding has both ends connected to the medium-voltage line terminal and a high-voltage line terminal led out from the center in the axial direction, and the above-mentioned part of the series winding near the high-voltage line terminal facing the series winding. In a transformer winding structure in which an insulator is provided in a shunt winding, a portion near the medium voltage line terminal facing the tertiary winding of the shunt winding and a region facing the series winding of the shunt winding A transformer winding structure characterized in that an insulator is provided near the intermediate voltage neutral point terminal and the intermediate voltage neutral point terminal.