JPH04180207A - Disk winding for induction electric apparatus - Google Patents

Abstract

PURPOSE:To prevent a partial and excessive temperature rise by a method wherein one cooling region is formed of a plurality of horizontal cooling passages between an inside blocking-up stopper and an outside blocking-up stopper which are installed side by side and a specific relationship is established among the following: the width of the horizontal cooling passages; the number of horizontal cooling passages inside one cooling region; and the width of an inside vertical cooling passage and an outside vertical cooling passage. CONSTITUTION:The number of horizontal cooling passages 5 in each cooling region is designated as (n); the height of the horizontal cooling passages 5 is designated as SH; and the width of an inside vertical cooling passage and an outside vertical cooling passage 8, 9 is designated as SV. The individual values SV, SH, (n) are set so that the relationship of SV>=(SHXn)/3 is established. That is to say, since the width of the inside and outside vertical cooling passages 8, 9 is kept at 1/3 or higher of the width of all the horizontal cooling passages 5 inside one cooling region, the difference in the speed of a refrigerant between the upper part and the lower part of the inside and outside vertical cooling passages 8, 9 in one cooling region is reduced. Consequently, the distribution of the speed of the refrigerant which flows into the horizontal cooling passages which are branched from the inside and outside vertical cooling passages is made uniform. Thereby, it is possible to prevent that the temperature rise of a disk winding becomes partially excessive, and the disl winding as a whole can uniformly be cooled.

Description

[Detailed Description of the Invention] [Object of the Invention] (Field of Industrial Application) The present invention relates to an induction electric disk winding that is cooled by a refrigerant such as SF6 gas or transformer oil, and particularly relates to an induction electric disk winding that is cooled by a refrigerant such as SF6 gas or transformer oil. Concerning possible induction electric disc windings.

(Prior Art) Conventionally, a disk winding used as a winding for an induction electric device such as a transformer is constructed as shown in a radial cross-sectional view in Fig. 4 and a cross-sectional view taken along the line ■-V in Fig. 5. . That is, between the inner insulating tube 1 and the outer insulating tube 2, a plurality of disk windings 3 each having a wire conductor wound thereon are stacked at intervals in the axial direction, and each disk winding serves as a crossover wire. (not shown) electrically connected in series.

Further, the disc windings 3 are separated from each other in the radial direction by insulating spacing pieces 4 arranged radially at equal intervals. As a result, a horizontal cooling path 5 for the disk winding 3 is formed between each disk winding 3 in the axial direction, which extends in the radial direction while being sandwiched between adjacent insulating spacing pieces 4 . Further, between the inner and outer insulating cylinders 1 and 2 and each of the disk windings 3, an inner vertical spacing piece 6 and an outer vertical spacing piece 7 or an insulating spacing piece 4 are provided on the same diameter as the insulating spacing piece 4, respectively. Inner insulating tube 1 and outer insulating tube 2, respectively
The horizontal cooling passages 5 are installed in close contact with each other and extend in the axial direction, and partition the adjacent horizontal cooling passages 5 in the axial direction. Between the adjacent inner and outer vertical spacing pieces 6 and 7, that is, between the disc winding 3 and the inner and outer insulating cylinders 1 and 2, each extends in the axial direction and communicates with a plurality of horizontal cooling passages 5. A plurality of inner vertical cooling passages 8 and outer vertical cooling passages 9 are formed.

This disk winding is stored in a tank (not shown) together with an insulating refrigerant such as an insulating gas such as SF6 gas or an insulating oil for a transformer, and this refrigerant is forced to flow or naturally convect to form the inner and outer vertical It is made to flow through the cooling paths 8 and 9 and the horizontal cooling path 5 to cool the disk winding 3.

In order to further enhance the cooling effect, such a disk winding is provided with disk windings in the inner vertical cooling path 8 and the outer vertical cooling path 9 every several stages of the disk winding 3, as shown in FIG. Inner plugs 10 and outer plugs 11 are provided alternately in the axial direction along the entire circumference of the line 3, and the inner and outer vertical cooling passages 8 and 9 are alternately closed in the axial direction. As a result, the adjacent inner plugs 10
A cooling zone is formed between and the outer plug 11 for the several stages of disc windings 3 accommodated therein.

Therefore, the refrigerant travels in a zigzag manner in the horizontal cooling channel 5 for each cooling zone in order to alternate between the inlet and the outlet for each cooling zone in the axial direction of the induction electric disc winding. That is, the refrigerant reliably travels through the horizontal cooling path 5 as well as the inner and outer vertical cooling paths 8 and 9, and the entire induction electric disk winding is efficiently cooled.

(Problem to be Solved by the Invention) However, in such an induction electric disk winding, when looking at the flow of refrigerant that is divided into each horizontal cooling path 5 in one cooling area, as shown in FIG. , the flow velocity is not uniform in the horizontal cooling passages 5 of each stage, and in the case of SF6 gas refrigerant, the flow velocity in the lower horizontal cooling passage 5 near the inlet of one cooling zone is not uniform near the outlet. The flow velocity in the upper horizontal cooling passage 5 is very small compared to that in the upper horizontal cooling passage 5. The horizontal length of the arrow 12 indicating the refrigerant path represents the magnitude of the flow velocity.

That is, the flow velocity distribution of each horizontal cooling passage 5 within one cooling area becomes smaller as it approaches the inlet of one cooling area, and especially near the inlet where the flow velocity of the inner and outer vertical cooling passages 8 and 9 is high. In this case, stagnation or backflow may also occur.

This is because when looking only at the horizontal cooling passage 5, there is almost no difference in the flow velocity of the refrigerant between the upper horizontal cooling passage and the lower horizontal cooling passage, but the passage width of the inner and outer vertical cooling passages 8.9 If the horizontal cooling channels are narrow compared to that of the horizontal cooling channels, - the flow resistance of the inner and outer vertical cooling channels 8,9 increases in the cooling zone, and the flow velocity of the coolant at the top and bottom of the inner and outer vertical cooling channels 8,9 increases; It makes a big difference (carryer at the top, faster at the bottom). Therefore, near the inlet where the flow velocity is high, the refrigerant is sucked in from the nearby horizontal cooling path 5, and the flow velocity of the refrigerant moving upward is canceled out or made negative.

Therefore, the disk winding 3 placed near the inlet is not sufficiently cooled compared to the disk winding 3 placed near the outlet. For this reason, the inner and outer obturators 10.
11 to ensure that the refrigerant passes through the horizontal cooling path 5, the cooling effect of each disk winding 3 cannot be obtained in each cooling zone. Therefore, it is not possible to equalize the temperature of the disc winding, and an excessive temperature rise occurs locally in each cooling zone, which deteriorates the insulation spacer 4 etc. that insulates the disc winding 3, resulting in voltage transformation. This may shorten the life of the device.

Therefore, is it possible to consider a winding cooling design based on the minimum flow velocity of the refrigerant in the horizontal cooling path 5, such as increasing the cross-sectional area of the wire conductor forming the disk winding 3 to lower the current density? There are disadvantages such as the large size of the container and high cost.

The present invention has been made in consideration of the above-mentioned circumstances, and it is possible to secure the flow rate necessary for cooling each horizontal cooling path for the refrigerant passing through the cooling area without increasing the size of the induction device.
It is an object of the present invention to provide an induction electric disk winding that can be cooled without causing an excessive temperature rise in some parts.

[Structure of the invention]

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a disc winding arranged in multiple stages in the axial direction between an inner insulating cylinder and an outer insulating cylinder, and a disc winding. a plurality of insulating spacing pieces extending in the axial direction while partitioning each disc winding in the radial direction, forming a plurality of horizontal cooling passages for the disc winding extending in the radial direction between adjacent insulating spacing pieces; a plurality of inner vertical spacing pieces extending in the axial direction and interposed between the inner insulating cylinder and the disc winding on the same diameter as the insulating spacing pieces,
between an inner vertical spacing piece that forms an inner vertical cooling passage that communicates with the horizontal cooling passage between adjacent inner vertical spacing pieces, and the outer insulating cylinder and the disc winding on the same diameter as the insulation spacing piece; a plurality of outer vertical spacing pieces extending in the axial direction and interposed between the outer vertical spacing pieces, the outer vertical spacing pieces forming an outer vertical cooling passage communicating with the horizontal cooling passage between adjacent outer vertical spacing pieces; , inner and outer blocking plugs are arranged alternately in the inner vertical cooling path and the outer vertical cooling path, respectively, in the axial direction over the entire circumference of the disk winding in the inner vertical cooling path and the outer vertical cooling path; In the induction electric disc winding, the induction electric disc winding includes an inner blocker and an outer blocker, the plurality of horizontal cooling paths forming one cooling zone between the adjacent inner blocker and outer blocker, wherein the horizontal cooling Channel width 5l11 An induction electric appliance that holds the relationship S≧(SHXn)/'3 between the number n of horizontal cooling channels in one cooling zone and the width S of the inner and outer vertical cooling channels. Disk windings are provided.

(Function) In the induction electric disk winding according to the present invention, the height SH of the horizontal cooling passages, the number n of horizontal cooling passages constituting one cooling area, and the width S of the inner and outer vertical cooling passages are S , ≧(
It satisfies the relationship S Hx n )/3. That is,
Since the width of the inner and outer vertical cooling channels is kept at least 1/3 of the width of all horizontal cooling channels in one cooling zone, the flow resistance of the inner and outer vertical cooling channels is smaller than that of the horizontal cooling channels. - the coolant flow velocity difference between the upper and lower parts of the inner and outer vertical cooling channels in the cooling zone is reduced; Therefore, the flow velocity distribution of the refrigerant flowing into the horizontal cooling path branching from the inner and outer vertical cooling paths becomes uniform.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3.

The basic configuration of the induction electric disc winding according to this embodiment is as follows:
Since it is not substantially different from that shown in FIG.
Corresponding parts are denoted by the same reference numerals and explanations will be omitted.

FIG. 1 is an axial sectional view of the induction electric disc winding of this embodiment, and corresponds to FIG. 5.

Here, as shown in the figure, horizontal cooling channels 5 in each cooling zone
The number of nl is the height of this horizontal cooling passage 5.
Assuming that the width of the outer vertical cooling passages 8 and 9 is Sv, in this embodiment, Sv≧(SHXn)/3...!・(1)
Multi-value SV, SH, n are set so that the following relationship holds true.

The induction electric disk winding of this embodiment configured in this way has S
When an insulating cooling medium such as F6 gas flows, the width S of the inner and outer vertical cooling channels is kept at least 1/3 of the width (S)Ixn) of all horizontal cooling channels in one cooling area. Therefore, the flow resistance of the inner and outer vertical cooling passages 8°9 is reduced compared to the horizontal cooling passage, and in addition to the fact that the difference in refrigerant flow velocity between the upper horizontal cooling passage and the lower horizontal cooling passage is small. , - the coolant flow velocity difference between the upper and lower parts of the inner and outer vertical cooling channels in the cooling zone is also reduced. Therefore, the flow velocity distribution of the refrigerant in each horizontal cooling path branching from the inner and outer vertical cooling paths is made uniform.

Figures 2 (A) and (B) are 5V=1°3x (
S xn)□/3 (i.e. S ≧(SHXn
Vn)/3) and 5
v=0.7×(SHXn)/3 (i.e. S < (
In the case of SHXn)/3), (1) shows the flow velocity distribution of the refrigerant in each horizontal cooling path in one cooling area.

Figure 2 (A) shows the flow velocity distribution of the refrigerant in this embodiment. In the induction electric disc winding of this embodiment, the flow velocity distribution in each horizontal cooling path within one cooling area is made uniform. On the other hand, if the formula (1) of the present invention does not hold between S, SH, and n, the flow velocity becomes zero near the bottom of one cooling zone, and the flow velocity in the horizontal cooling channel at the top and bottom becomes zero. There is a big difference.

Figure 3 is a graph showing the relationship between (SHXn)/''S and the maximum temperature of the disk winding, 3 HX n7S~7
There is an inflection point near =3. I want to do it (S X n
) 7' S y≦3, that is, S ≧(S xH
In the region of ˜H n)/3, a relatively uniform flow velocity distribution as shown in FIG. 2(A) is obtained, so the maximum temperature of the disk winding is low. On the other hand, (S HX n ) /S >'3
That is, in the region where the slope is < (SHXn)/3, the maximum temperature of the disc winding is considered to be high because the flow velocity distribution is as shown in FIG. Note that Sl; (S HX n ) / 3 is the limit condition where stagnation or backflow does not occur.

According to this embodiment, in order to set the multi-values S, ..., SH,n so that the above formula (1) holds true, the refrigerant flow velocity in each stage of the horizontal cooling path is made uniform, and the circular Cooling efficiency can be improved by eliminating the problem that the temperature rise of the plate winding becomes excessive in some parts. Therefore, it is possible to increase the current density by reducing the cross-sectional area of the wire conductor forming the disk winding, and it is possible to reduce the size and weight of the induction electric disk winding.

〔Effect of the invention〕

As explained above, according to the induction electric disk winding of the present invention, it is possible to uniformly cool the entire disk winding, thereby reducing the size and improving the economic efficiency of the induction electric disk winding. I can do it.

[Brief explanation of the drawing]

FIG. 1 is an axial cross-sectional view of a main part of an induction electric disk winding according to an embodiment of the present invention, and FIG. Fig. 2 (B) is a graph showing the flow velocity distribution of the cooling passages, and Fig. 3 is a graph showing the flow velocity distribution of each horizontal cooling passage in the cooling zone of the induction electric disk winding that does not meet the requirements of the present invention. The figure is (SHXn)/Sv
Graph showing the relationship between the value of and the maximum temperature of the disk winding, 4th
The figure is a radial cross-sectional view of a conventional induction electric disk winding, and FIG. 5 is a cross-sectional view taken along the line V-V in FIG. 4. DESCRIPTION OF SYMBOLS 1...Inner insulating tube, 2...Outer insulating tube, 3...Disc winding, 4...Insulating spacing piece, 6...Inner vertical spacing piece, 7...Outer vertical spacing piece , 5... horizontal cooling path, 8.
...Inner vertical cooling path, 9...Outer vertical cooling path, 10.
...Inner obstructing plug, 11...Outer obstructing plug. Agent Patent Attorney Rules Ken Chika Velocity Flow Velocity (A> Sv ≧ Pkn4 Go (B) Sv <”'
"f') 4 Goji 2 times Sv Name 3 Hi

Claims (1)

[Claims] A disc winding arranged in multiple stages in the axial direction between an inner insulating cylinder and an outer insulating cylinder, and a plurality of insulation intervals extending in the axial direction while partitioning each disc winding in the radial direction of the disc winding. an insulating spacing piece that forms a plurality of horizontal cooling passages for a disc winding extending radially between adjacent insulating spacing pieces; A plurality of inner vertical spacing pieces are interposed between the plate windings while extending in the axial direction, and an inner vertical cooling passage communicating with the horizontal cooling passage is formed between adjacent inner vertical spacing pieces. an inner vertical spacing piece; and a plurality of outer vertical spacing pieces that are interposed between the outer insulating cylinder and the disc winding on the same diameter as the insulating spacing pieces while extending in the axial direction, and that are adjacent to each other. an outer vertical spacing piece forming an outer vertical cooling passage communicating with the horizontal cooling passage between the outer vertical spacing pieces; and an outer vertical spacing piece forming an outer vertical cooling passage communicating with the horizontal cooling passage; Inner and outer blocking plugs are arranged alternately in the inner vertical cooling path and the outer vertical cooling path, respectively, and one cooling is performed in the plurality of horizontal cooling paths between adjacent inner and outer blocking plugs. In an induction disk winding comprising an inner blocker and an outer blocker forming a zone, the width S_H of the horizontal cooling channel, the number n of horizontal cooling channels in one cooling zone, and the inner
Between the width S_v of the outer vertical cooling passage, S_v≧(S_HX
An induction electric disk winding that satisfies the relationship of _n)/3.