JPS6320368B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a self-cooled stationary induction electric appliance winding, and more particularly to the configuration of a cooling oil passage for a disk winding or helical winding in a self-cooled transformer or reactor.

When the voltage is high in a conventional self-cooling transformer, as shown in Fig. 1, a structure in which an outer insulating tube 11 is provided on the outside of the disk winding 1 (abbreviated as disk winding structure with outer tube) is used. ) is used and the voltage is low, then
As shown in Fig. 3, a disc winding 1 and an oil free space 1
A structure (abbreviated as a disk winding structure without an outer cylinder) was used in which the wires were in direct contact with each other. Hereinafter, these two types of winding structures will be explained using FIGS. 1 to 4.

In the disk winding structure with an outer cylinder shown in FIG. 1, coils 2 are wound in a plate shape around the outer periphery of an iron core, and horizontal oil passages 3 are formed through horizontal spacers each having a predetermined height. , are stacked in the height direction, and arranged so as to form an inner vertical oil passage 5 on the outside of the inner insulating cylinder 4 via an inner vertical spacer, and furthermore, an outer vertical spacer is placed on the outside of the winding 1. The outer insulating cylinder 11 is arranged through the outer vertical oil passage 6 to form the outer vertical oil passage 6, and the inner oil flow guide plate 7 that blocks the inner vertical oil passage 5 and the outer oil flow guide plate 12 that blocks the outer vertical oil passage 11. was placed. (Hereinafter, the section in the height direction of the winding 1 that is divided by the member that blocks the vertical oil passage is referred to as the fold section.) Also, in the circumferential direction of the winding 1, the structure is almost the same. was.

In such a winding structure, the coil 2 is cooled by flowing oil as shown by the arrow in Fig. 1, but the oil flow rate distribution in the folded flow section is as shown by the curve Q ₀ in Fig. 2. , the temperature rise in the coil 2 becomes uneven, as shown by the curve T ₀ , and increases in the lower part of the flow section (for example, a, b) and decreases towards the upper part. In No. 3, there was a tendency for the temperature to become locally high in the upper part of the flow section (for example, y, z) where the oil flow rate was low.

In addition, the disk winding structure without an outer cylinder shown in FIG.
1 is not provided, the outer peripheral end of the coil 2 is brought into direct contact with the oil free space 13, and an inner oil flow guide plate 7 that closes the inner vertical oil passage 5 is arranged for every predetermined number of coils.

In such a winding structure, the coil 2 is cooled by flowing oil as shown by the arrow in Fig. 3, but the oil flow distribution within the fold section is as shown by the curve Q' ₀ in Fig. 4. In this case, the temperature rise of the coil 2 is higher in the lower part (e.g. a, b) and upper part (e.g. y, z) of the folded flow area, and less in the middle part of the folded flow area, and as a result, the temperature rise of the coil 2 is
As shown by T' ₀ , there was a tendency for the temperature to become locally high in the central part of the diversion section of horizontal oilway 3 where the oil flow rate was low.

As one method for correcting such non-uniform temperature rise in the windings, as described in Japanese Patent Application Laid-Open No. 73216/1983, the folded sections in the height direction are divided into predetermined blocks in the circumferential direction. A method has been considered in which the folded sections are arranged in a staggered manner when the windings are expanded in the circumferential direction. According to our experiments using transformer windings, in self-cooled transformers, the oil flow velocity in the flow section is proportional to the oil flow rate, and the maximum is several cm/sec.
It was found that in the self-cooling region, the heat dissipation coefficient of the coil is proportional to the oil flow velocity to the 0.3 power.
Therefore, in order to use the method described above to uniformly cool each part of the winding using heat conduction in the circumferential direction of a coil that is locally hot, the oil flow velocity must be small enough to have a sufficient effect. It has become clear that the drawback is that it is difficult to obtain. In addition, to avoid this, it is possible to reduce the number of coils in the flow section and configure the above-mentioned staggered arrangement to increase the oil flow velocity in the flow section. In order to achieve this, the total number of folded flow sections in the winding must be approximately doubled, and as a result, the pressure loss in the winding increases, the oil flow rate decreases, and the maximum oil temperature of the transformer increases. It has also become clear that there are drawbacks.

The purpose of the present invention is to correct uneven temperature rise without significantly increasing pressure loss in the winding section,
The purpose is to provide self-cooled stationary induction electric windings with almost uniform temperature rise.

In order to achieve this object, the present invention provides a first fold section having a predetermined number of coils in the circumferential direction and a height direction, and a second fold section formed by dividing the first fold section. The coils are arranged alternately, and the coils that become locally hot in the first folded flow section utilize heat conduction by the high-speed oil flow flowing through the adjacent second folded flow section. In addition to effective cooling, the pressure loss in the winding section is reduced in the circumferential direction by alternately arranging the first fold section with a large number of coils and the fold section with a small number of coils in the height direction. It is characterized in that it is made even and does not increase significantly.

Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

5 to 9 show examples in which the present invention is applied to a structure provided with an outer insulating tube 11 (disc winding with an outer tube). In this embodiment, as shown in a perspective view in FIG. In addition to the inner and outer oil flow guide plates (hereinafter referred to as first oil flow guide members), the inner circumference or outer circumference is arranged in predetermined blocks in the circumferential direction as shown in FIGS. 7a to 7f. Alternatively, a second insulating plate made of a ring-shaped insulating plate with cutouts on the inner and outer peripheries
The oil flow guide members 14a to 14c are arranged between the horizontal spacers 8 of the winding 1.

FIG. 8a shows the -' cross section of FIG. 5, and FIG.
A second oil flow guide member having a shape shown in 14a,
In the order of 14b and 14c, between the next outer oil flow guide plates 12 and 7, a second oil flow guide member 14c having the shape shown in FIGS. ', 14b', and 14a' are arranged in this order. Here, the second oil flow guide members 14a' to 14
c' is obtained by shifting 14a to 14c by a predetermined block in the circumferential direction. Then, there is a folding section composed of the first oil flow guide member (inner oil flow guide plate) 7 and the second oil flow guide member 14b, and the first oil flow guide member (outer oil flow guide plate) 12 and the second oil flow guide member (outer oil flow guide plate) 14b. The flow section composed of the two oil flow guide members 14b is referred to as the first flow section A,
Second oil flow guide members 14b and 14c, and 14
c and 12, and 14b' and 14a', and 14
The fold section composed of a' and 7 will be referred to as the second fold section B. That is, in FIG. 8a, the first fold section A and the fold section B, in which the number of coils in the fold section is about half of the first fold section A, are arranged in the height direction from A, B. , B, A, and so on.

In the block Y (indicated by the line Y-Y') adjacent to the block X in the circumferential direction shown by the line -' in FIG. 5, the first and second fold sections A, The arrangement of B is B, B, A, B, B from the bottom...
be configured in this order. As a result, in the height direction of the winding, the first folding section A and the second folding section B are arranged alternately every predetermined length, and also in the circumferential direction, the first folding section A and the second folding section B are arranged alternately at predetermined lengths. The two folding sections B are arranged so as to be adjacent to each other.

Next, the temperature rise characteristics of the coil will be explained. Q _a and Q _b in FIG. 9 are oil flow rate distribution curves in the first fold section A and the second fold section B, respectively;
T _a and T _b are respectively the entire circumference of the winding, which is the first folding section A;
The temperature rise distribution curve T is the temperature rise distribution curve of the transformer winding of this embodiment when the second fold section B is configured.

Now, as shown in Fig. 5, consider two winding blocks adjacent to each other in the circumferential direction, and in a winding section in a certain height direction, a first fold section A and a second fold section B are formed.
Assuming that these belong to block X and block Y, respectively, the oil flow rate distribution curves Q _a and
It will be cooled by the oil flow corresponding to Q _b . Therefore, if there is no heat transfer between block X and block Y, the temperature rise distribution of the coil corresponding to each oil flow will be T _a and T _b ,
In this example, there are two blocks: a first fold section A where local high temperature areas tend to occur, and a second fold section A where the average oil flow velocity in the fold section is approximately twice that of the first fold section A. Since the flow zone B is adjacent to the flow zone B in the circumferential direction, if a temperature gradient occurs in the circumferential direction of the coil 2, heat will move in the circumferential direction due to heat conduction of the coil conductor, and the temperature of each part will be averaged. As shown by the temperature rise curve T, the temperature becomes intermediate between T _a and T _b . the result,
The temperature difference ΔT between the highest and lowest temperature rises in the coil 2 of the transformer winding is significantly smaller than in the conventional structure, and the entire winding can be cooled almost uniformly.

10 and 11 show other embodiments in which the present invention is applied to a structure in which the disk winding 1 and the oil free space 13 are in direct contact (disc winding without an outer cylinder). In this embodiment, in addition to the outer oil flow guide plate 7 used in the conventional structure, a second oil flow guide member 14c as shown in FIGS. 14c' shifted by 14c' is placed between the horizontal spacers 8 of the winding 1. That is, as shown in FIGS. 10a and 10b, the second oil flow guide members 14c and 14c' are arranged alternately across the first oil flow guide plate 7 in the height direction of the winding 1. Place it in For example, in a certain circumferential block (block In the block Y in the direction, as shown in FIG. 10b, the configuration of the fold sections is A, B, B, A, . . . from the bottom.
As a result, in the height direction of the winding, the first folding section A and the second folding section B are arranged at predetermined lengths, and also in the circumferential direction, the first folding section A and the second folding section B are arranged. The flow section B is arranged so as to be adjacent to the flow section B. Therefore, in this embodiment as well, the same effects as in the embodiment shown in FIGS. 8a and 8b can be obtained.

FIG. 11 is a diagram showing the oil flow rate distribution in the horizontal oilway and the temperature rise distribution in the coil of this embodiment. _If there is _{no heat} transfer between _block Blocks X and Y are adjacent to each other in the circumferential direction, so if a temperature gradient occurs, heat will move in the circumferential direction due to heat conduction in the coil conductor, and as a result, the temperature of each part will change to a temperature increase distribution. It can be averaged as shown by curve T'. Furthermore, the temperature difference ΔT' between the highest and lowest temperature rises of the coil 2 can be significantly reduced compared to the conventional structure.

FIG. 12 shows the structure of the present invention (curve T ₁ ) and another conventional structure according to Japanese Patent Application Laid-open No. 73216/1983 (curve T 1 ) in which folded sections are arranged in a staggered manner for a winding with an outer cylinder. This is a comparison of the effects of T ₂ ). As described above, according to the present invention, the oil flow velocity in the coil, which locally becomes high temperature in the first folding section A, and the second folding section B, which is circumferentially adjacent to the coil, is reduced by about 100% compared to the conventional structure. Since it can be doubled or more, the temperature of the coil can be lowered over the entire winding as shown in FIG. In the figure, _T3 indicates oil temperature.

In the embodiments shown in FIGS. 8 and 10, the first folding section A and the second folding section B adjacent to the circumferential direction divide the first folding section A into two in the height direction. However, the present invention is not limited to two divisions, and may be divided into a desired number of divisions to further increase the average oil flow velocity in the second fold section B. However, as the number of divisions increases, the pressure loss in the winding section increases, which is a drawback.
Furthermore, in FIGS. 8 and 10, the second fold section B is configured to have equal lengths, but the present invention is not limited to the case where the lengths are equal; It goes without saying that this also includes cases in which the cooling effect is maximized depending on the temperature and oil flow distribution characteristics of A, and the division is unevenly divided.

Furthermore, other embodiments of the present invention are shown in FIG.
This will be explained using Figure 4. In FIG. 13, a first folding section A and a second folding section B are arranged adjacent to each other in predetermined sections Z ₁ and Z ₂ including a plurality of circumferential blocks. In this embodiment, when the number of blocks in the circumferential direction of the winding 1 increases, as in the embodiment shown in FIG. Compared to the case where the second folding section B is made adjacent to each other, the number of notches in manufacturing the second oil flow guide member 14 is reduced, so there is an advantage that manufacturing becomes easier.

FIG. 14 is an example in which the present invention is applied to the upper section of the winding 1 indicated by _H1 . In this embodiment, if the temperature rise of the winding in the upper section of the winding is expected to exceed a predetermined limit value due to a rise in oil temperature, it is possible to relatively easily lower that part to within the limit value. There are advantages. Furthermore, in this embodiment, if a part of the winding is expected to become hot due to adjustment of ampere turns between high and low voltage windings, the same effect can be obtained by applying it only to that part. .

As described above, according to the present invention, the temperature of the coil can be made almost uniform throughout the entire winding, and local high-temperature parts can be removed, thereby preventing deterioration of the insulation and insulating the static induction appliance. It can improve durability. In addition, since the maximum temperature rise of the winding is reduced, it is possible to raise the operating temperature of the self-cooled static induction electric appliance winding with the same specifications, increasing the current density accordingly and increasing the capacity of the static induction electric appliance. Can be done.

[Brief explanation of the drawing]

Figures 1 and 3 are longitudinal cross-sectional views of conventional self-cooling transformer windings, and Figures 2 and 4 are Figures 1 and 3, respectively.
Fig. 5 is a diagram of the oil flow distribution in the horizontal oil pipe and the temperature rise distribution of the coil in the winding structure shown in the figure. FIG. 6 is a perspective view of the self-cooling transformer winding, and FIGS. 7 a to f are plan views of the second oil flow guide member used in the self-cooling transformer winding. , Figures 8a and b are cross-sectional views taken along lines X-X' and Y-Y' in Figure 5, respectively, and Figure 9 shows the oil flow distribution in the horizontal oil passage of the self-cooling transformer winding and the coil. Temperature rise distribution map, 1st
0A and 0B are longitudinal cross-sectional views of various parts of a self-cooling transformer winding according to another embodiment of the present invention, and FIG. FIG. 12 is a temperature rise distribution diagram of coils of the structure of the present invention and other conventional structures, and FIGS. 13 and 14 are self-cooling type transformers according to still other embodiments of the present invention. FIG. 3 is a developed view in the circumferential direction for explaining the arrangement of folded sections of the winding. 1...Disc winding, 2...Coil, 3...Horizontal oil pipe, 4...Inner insulating tube, 5...Inner vertical oil pipe, 6
...Outer vertical oil pipe, 7...Inner oil flow guide plate (first
oil flow guide member), 8...horizontal spacer, 9...
Inner vertical spacer, 10... Outer vertical spacer,
DESCRIPTION OF SYMBOLS 11...Outer insulating cylinder, 12...Outer oil flow guide plate (first oil flow guide member), 13...Oil free space, 1
4a to 14c, 14a' to 14c'...Ring-shaped insulating plate (second oil flow guide member), A...first fold section,
B...Second folding area.

Claims (1)

[Claims] 1 A disc-shaped winding is formed by stacking a plurality of coils in the height direction via horizontal spacers so as to form horizontal oil passages between them, and this disc-shaped winding is The disk-shaped winding is circumferentially divided by the horizontal spacer and the inner vertical spacer so as to form an inner vertical oil passage outside the inner insulating cylinder via an inner vertical spacer. A plurality of first oil flow guide members forming a plurality of winding blocks and blocking at least the inner vertical oil passage all around the circumference are arranged at intervals in the height direction to form a folded flow section in the height direction. In the self-cooled stationary induction electric winding, a second oil flow guide member is provided between the first oil flow guide members to alternately block the vertical oil passages of the plurality of winding blocks in the circumferential direction. The positions of the winding blocks in the circumferential direction at which the vertical oil passages are blocked are staggered within the folded section in the height direction, and the first folded section has a predetermined number of coils in the circumferential direction and the height direction. A self-cooled stationary induction electric appliance winding characterized in that the first folded flow sections are divided and the second folded flow sections are arranged alternately. 2. In claim 1, an outer insulating cylinder is disposed via an outer vertical spacer so as to form an outer vertical oil passage outside the disc-shaped winding, and
The second oil flow guide member includes a ring-shaped insulating plate in which cutouts are provided on the inner periphery in units of predetermined winding blocks in the circumferential direction and that alternately block the inner vertical oil passages, and a ring-shaped insulating plate on the outer periphery that has notches provided in units of predetermined winding blocks in the circumferential direction. A ring-shaped insulating plate is provided with notches in units of predetermined winding blocks in the direction and alternately closes the outer vertical oil passage, and cutouts are provided in the inner and outer circumferential parts in units of predetermined winding blocks in the circumferential direction. 1. A self-cooled stationary induction electric appliance winding, characterized in that it is constructed using ring-shaped insulating plates that alternately block inner and outer vertical oil passages. 3. In claim 1, an oil-free space is provided without an outer insulating tube disposed outside the disc-shaped winding, and the second oil flow guide member is provided with a circumferential direction on the inner periphery. 1. A self-cooled stationary induction electric appliance winding, characterized in that it is constructed using ring-shaped insulating plates that are provided with notches in units of predetermined winding blocks and alternately block inner vertical oil passages.