JPH08273945A - Transformer winding - Google Patents

Abstract

PURPOSE: To obtain a transformer winding which suppresses local overheating so as to make a temperature rise distribution uniform and in which a winding diameter can be reduced by a method wherein ring-shaped buffle plates are installed along the inner circumference and the outer circumference of the winding, the flow in the vertical direction of an insulating coolant is suppressed and a continued spiral cooling duct is formed along the conductor of a helical winding. CONSTITUTION: A cooling duct is constituted in such a way that radial-direction duct pieces 3 which have sandwiched and bonded respective insulating materials 10, 11 excluding respective space parts 9 to be used as passages of an insulating coolant 8 between two insulating plates 6, 7 comprising respective cutout parts 5 used to fix a longitudinal duct piece 2 at both ends in the length direction are arranged between respective winding parts for a helical winding. Ring-shaped buffle plates 12, 13 are arranged along the inner circumference and the outer circumference in the part of the cooling duct, the flow in the vertical direction of the insulating coolant 8 is suppressed, and a continued spiral cooling duct is formed along the conductor of the helical winding. Thereby, the insulating coolant 8 flows uniformly into a horizontal duct inside the winding, and it is possible to obtain a transformer winding in which the lack of uniformity of a temperature rise distribution and local overheating are suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helical winding (Wendel winding) used in a transformer having a relatively large capacity, and more particularly to a cooling structure thereof.

[0002]

2. Description of the Related Art Conventional helical winding (Wendel winding)
In this case, as in the case of the disk winding (disk winding), a split flow division method using a baffle, or an intermediate duct method in which a passage for an insulating cooling insulating medium is provided in the middle of the winding is used.

FIG. 5 is a block diagram showing the structure of a disk winding of a transformer. As shown in FIG. 5, the disk winding 21 is a disk-shaped unit disk coil 22 wound in the radial direction. The radial duct pieces 24, which are evenly arranged in the circumferential direction of the insulating cylinder 23, are sandwiched and overlapped in the axial direction.

FIG. 6 is a block diagram showing the structure of the helical winding of the transformer. As shown in FIG. 6, the helical winding 25 is formed by stacking a plurality of conductors in the radial direction and arranging the insulating cylinder 23 in the circumferential direction. The radial duct pieces 24, which are evenly arranged, are sandwiched between the windings and spirally wound in the axial direction.

FIG. 7 is a vertical cross-sectional view showing a cooling structure of a transformer winding with a split-flow segmentation method. As shown in FIG. 7, the split-flow segmentation method uses a radial duct piece between unit disk coils 22. 24
The disk winding 21 wound via the disk winding 21 is divided into a plurality of flow-divided areas A, B, C and D (here, the case is shown as being divided into four) in the axial direction, and the disk winding 21 is divided. Insulation cylinders 28 and 29 inside and outside of the
And a vertical cooling duct 30 formed by the vertical duct pieces 26 and 27 and the insulating tubes 28 and 29.
And 31 are alternately closed by baffles 32 and 33 on the inner side and the outer side of the disk winding 21 arranged at the boundaries of each of the flow-flow sections A, B, C and D, thereby insulating cooling medium (for example, insulating oil). ) 34 flows in a zigzag manner from the lower side to the upper side of the disk winding 21. In this way, the insulating cooling medium 34 is evenly distributed in the horizontal cooling duct 36 formed by the radial duct piece 35.
The cooling effect of the disk winding 21 is enhanced by flowing the current. In addition, this split-flow section method can also be applied to a helical winding.

FIG. 8 is a sectional view showing an intermediate duct type cooling structure of a transformer winding, and FIG. 9 is a sectional view showing a structure of an insulating band used as an intermediate duct. As shown in FIGS. 8 and 9, Since the intermediate duct system forms an intermediate duct, the conductor of the disk winding 21 wound between the unit disk coils 22 (between the conductors in the case of a helical winding) via the radial duct piece 35. During winding, the insulating strip 39 having the insulating piece 38 attached thereto is sandwiched and wound on the strip-shaped insulating paper 37, and the unit disk coil 22 sandwiched by the insulating strip 39 is The positions between the conductors are changed so as to form a zigzag shape when viewed from the vertical section, and the radial position of the flow of the insulating cooling medium 34 is changed. The intermediate duct method can also be applied to the helical winding.

[0007]

In the conventional split flow division method using a baffle, the flow rate of the insulation cooling medium is concentrated in a horizontal duct near the outlet of the insulation cooling medium in the split flow section. Therefore, there is a problem in that the temperature rise distribution of the windings becomes non-uniform because of the non-uniformity, and local overheating easily occurs.

Further, when the intermediate duct system is used, a better flow rate distribution and winding temperature rise distribution can be obtained by staggering the arrangement of the intermediate ducts.
Since the intermediate duct is provided in the winding, there is a problem that the winding size is expanded in the radial direction.

The present invention has been made in view of the above problems of the prior art, and provides a compact transformer in which local overheating is suppressed, the temperature rise distribution is uniform, and the winding diameter is small. The purpose is to do.

[0010]

In order to achieve the above-mentioned object, the transformer winding cooling structure according to the present invention comprises two sheets having notches at both ends in the longitudinal direction for fixing to a vertical duct piece. Radial duct pieces with insulating material sandwiched between insulating plates except for the space that serves as a passage for the insulating cooling medium are placed between each winding of the helical winding, and Installed a ring-shaped baffle plate along the inner and outer circumferences to prevent the insulating cooling medium from passing upward, and formed a continuous spiral cooling duct along the conductor of the helical winding.

[0011]

With the above structure, a spiral cooling duct in which the horizontal duct between windings is continuous is formed, and the insulating cooling medium uniformly flows into the spiral cooling duct in the winding. The uneven temperature distribution and local overheating can be suppressed, and since the thickness of the vertical duct piece can be small, the diameter of the winding can be reduced.

[0012]

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

FIG. 1 is a plan sectional view showing an embodiment of a transformer winding of the present invention, FIG. 2 is a sectional view showing an AA cross section of FIG. 1, and FIG. 3 is a sectional view taken along the BB line of FIG. 4 is an explanatory view of the configuration of the radial duct piece of the embodiment of the transformer winding cooling structure of the present invention, (A) is a cross-sectional view, (B) is a plan view, as shown in FIG. One end of the radial duct piece 3 (the inner circumferential side of the winding) is attached to the inner vertical duct piece 2 that is evenly arranged in the circumferential direction of the cylinder 1, and the radial duct piece 3 having a predetermined thickness is provided between the windings. A helical winding is formed by spirally winding in the axial direction a coil 4 in which a plurality of conductors are stacked in a radial direction.

In this case, the radial duct piece 3
As shown in FIG. 2, FIG. 3 and FIG. 4, an insulating cooling medium is provided between two insulating plates 6 and 7 having notches 5 for fixing to the vertical duct piece 2 at both ends in the longitudinal direction. Insulating materials 10 and 11 are arranged at both ends and sandwiched so as to have a space 9 which serves as a passage of 8. In the case of this embodiment, the position of the insulating material 10 is set to the winding thickness of the coil 4. Those provided on the outer side and those provided on the inner side are alternately arranged on the circumference from the middle.

Further, baffle plates 12 and 13 on the ring are installed along the inner circumference and the outer circumference of the portion that has existed as the conventional vertical cooling duct, thereby preventing the vertical flow of the insulating cooling medium 8. Then, a spiral cooling duct that is continuous along the conductor of the helical winding is formed, and the space portion 9 that serves as a passage for the insulating cooling medium 8 has a radial duct piece 3
It becomes a state of meandering inside and outside.

In this case, the radial duct pieces 3 are evenly distributed, and the outer longitudinal duct pieces 14 are provided in the notches 5 at the other ends of the radial duct pieces 3 (outer peripheral side of the winding).
Is inserted, and the insulating cylinder 15 is arranged on the outer side thereof.

[0017]

Since the present invention is configured as described above, the following effects can be obtained.

(1) By disposing the radial duct piece provided with the oil passage between the coils of the helical winding, the horizontal duct between the coils can be made into a continuous spiral cooling duct. The insulating cooling medium uniformly flows into the horizontal duct, and uneven distribution of temperature rise and local overheating can be suppressed.

(2) The thickness of the conventional vertical duct piece is larger than the thickness for supporting the radial duct piece, but is determined by the thickness required for cooling, but a spiral cooling duct is formed. Therefore, the thickness of the vertical duct piece may be small and the dimension of the winding diameter is small.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an embodiment of a transformer winding of the present invention.

FIG. 2 is a cross-sectional view showing an AA cross section of FIG.

FIG. 3 is a cross-sectional view showing a BB cross section of FIG.

FIG. 4 is an explanatory view of a configuration of a radial duct piece of an embodiment of the transformer winding cooling structure of the present invention.

FIG. 5 is a configuration diagram showing a structure of a disk winding of a transformer.

FIG. 6 is a configuration diagram showing a structure of a helical winding of a transformer.

FIG. 7 is a cross-sectional view showing a cooling structure of a transformer winding with a split-flow type.

FIG. 8 is a cross-sectional view showing an intermediate duct type cooling structure for transformer windings.

FIG. 9 is a cross-sectional view showing a structure of an insulating strip used as an intermediate duct of a transformer winding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating cylinder 2 ... Inner vertical duct piece 3 ... Radial duct piece 4 ... Coil 5 ... Notch part 6, 7 ... Insulating plate 8 ... Insulating cooling medium 9 ... Space part 10, 11 ... Insulating material 12 ... Inner baffle plate 13 Outer baffle plate 14 Outer vertical duct piece 15 Outer insulating cylinder

Claims (1)

[Claims] 1. A helical transformer comprising a plurality of conductors that are stacked in a radial direction, radial duct pieces that are evenly arranged in a circumferential direction are arranged between windings, and spirally wound in an axial direction. In the winding, a radial direction in which an insulating material is sandwiched between two insulating plates having notches for fixing to a vertical duct piece at both ends in the length direction except for a space portion which serves as a passage for an insulating cooling medium. A duct piece is placed between each winding of the helical winding to form a cooling duct, and ring-shaped baffle plates are installed along the inner and outer circumferences of the winding to block the vertical flow of the insulating cooling medium. A transformer winding is characterized in that a continuous spiral cooling duct is formed along the conductor of the helical winding.