JPS618909A - Winding construction of stationary induction electric apparatus - Google Patents

Abstract

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

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to a winding structure for a stationary induction appliance.

[Background of the invention]

FIG. 2 shows a conventional example of an SFs gas insulated transformer. As shown in the figure, the cylindrical winding 1 is arranged so that each winding unit (hereinafter referred to as a coil) 4 forms a plurality of vertical ducts 3 on the outer periphery of an inner insulating cylinder 2 wound around a core leg.
is wound with a vertical spacer 5 in between, horizontal spacers 6 are arranged at the upper and lower ends, and a horizontal duct 7 communicating with the vertical duct 3 is provided. The vertical ducts 3 are arranged at substantially equal intervals δ. In the figure, 8 is an insulating ring, and 9 is an outer insulating cylinder.

In the SF6 gas insulated transformer configured in this way, the cooling medium flows from the horizontal duct 7 at the bottom of the winding as shown by the arrow in the figure, and this flowing cooling medium flows into the coil 4.
Each coil 4 is cooled by rising through a vertical duct 3 between them. By the way, this refrigerant flow rate is almost equal in each vertical duct 3, and the amount of heat given to the vertical ducts 3 on the innermost and outermost sides of the winding 1 is about 1/2 that of the vertical duct 3 in the center, so cooling is The temperature rise of the medium is smaller than the temperature rise of the refrigerant in the other vertical ducts (3). The reason why the amount of heat given to the vertical ducts 3 on the innermost and outermost sides is about 1/2 that of the vertical duct 3 in the center is that the amount of heat given to the vertical ducts 3 in the center is smaller than that of the vertical ducts 3 in the center. The amount of heat given to the vertical ducts 3 on the innermost and outermost sides is only given from the coils 4 on the innermost and outermost sides, whereas the heat is given from the coils 4 on both sides of the sandwich. It is.

Therefore, the average temperature rise of each coil 4 is shown in Figure 3, where the temperature is plotted on the vertical axis and the coil number is plotted on the horizontal axis, showing the relationship between temperature and coil number. Ya1)
Also, the temperature of the outermost coil (house 4) was low, and the temperature of the central coil (cliff 2°3) was high, and the temperature of each coil tended to be uneven.

[Purpose of the invention]

The present invention was made in view of the above points, and makes it possible to equalize the temperature rise of each coil.
It is an object of the present invention to provide a winding structure for a stationary induction electric appliance. upper and lower horizontal spacers that communicate a plurality of winding units of cylindrical windings or sheet windings wound in a concentric cylindrical shape with the vertical duct to form horizontal ducts at the upper and lower ends of the winding units; In the winding structure of the stationary induction electric device arranged between the coils, the radial dimension of the vertical ducts on the innermost and outermost periphery sides is smaller than the radial dimension of the vertical ducts in other parts. As a result, the radial dimensions of the vertical ducts on the innermost circumferential side and the outermost circumferential side are formed to be smaller than the radial dimensions of the vertical ducts on the other parts.

[Embodiments of the invention]

The present invention will be explained below based on the illustrated embodiments. FIG. 1 shows an embodiment of the invention. Note that parts that are the same as those in the conventional system are given the same reference numerals, and therefore their explanations will be omitted. In this embodiment, the innermost circumferential side, I&, and A□. Yo@l',)
3゜□Ioe6. Oh,. It is made smaller than the radial dimension δ2 of the vertical duct 3 in other parts of f. By doing this, the radial dimension δl of the vertical duct 3 on the innermost and outermost periphery sides can be made equal to the radial dimension δ2 of the vertical duct 3 on the other parts.

The radial dimension δ1 of this vertical duct 3. δ2 can be determined as described below. Generally, the refrigerant flow rate Q (m"/S) of the vertical ducts 3 is distributed so that the pressure loss h (■Aq) between the vertical ducts 3 is equal. The pressure loss of the vertical ducts 3 is As shown in Fig. 4, the radial dimension δ (m) and the length L (m)
, and can be regarded as a rectangular duct with a length in the depth direction W (m ), and equation 0) can be approximately obtained by following the river.

Here, γ is the specific weight of the refrigerant (K9/m''), g is the gravitational acceleration (m/S2), and λ is the pipe friction loss coefficient.

In the case of a refrigerant with a low viscosity such as 8Fg gas, the pipe friction loss coefficient λ remains approximately constant even if the flow rate Q changes somewhat. Therefore, the value of λL/4gW' in equation (1) can also be considered constant in this discussion.The value of λL/4gW' can be
Then, the pressure loss is expressed by equation (2), and Q2/δ
Proportional to 8.

On the other hand, the amount of heat applied to the innermost and outermost vertical ducts 3 is about 1/1 of that of the central vertical duct 3, as described above.
2, so in order to equalize the temperature rise of the refrigerant in each vertical duct 3, the flow rate flowing through the innermost and outermost vertical ducts 3 should also be equal to the flow rate of the other central vertical ducts 3. It needs to be reduced to about 1/2. To achieve this (2
) formula, the radial dimension (spacing) of the vertical duct 3 when the refrigerant flow rate Q is halved under the condition that the pressure loss is constant.
All you have to do is find δ1. The other part, the radial dimension (distance) of the vertical duct 3 in the center, is set to δ as described above.
2, (1/2Q>”/al”=Q”/δ, s
・(3) becomes. Therefore, the relationship between the radial dimension δ1 of the vertical duct 3 on the innermost circumferential side and the outermost circumferential side and the radial direction dimension δ2 of the vertical duct 3 in other parts is obtained. In the actual manufacturing of the product, the variation in the refrigerant flow rate Q of the vertical duct 3 is ±2.
If approximately 0 is allowed, then the permissible value for the vertical duct spacing is (5) formula % formula % Therefore, the relationship between δ1 and δ2 is theoretically the value of formula (4), but in practice is set within the range given by equation (5).

, By making the radial dimension δ of the vertical duct 3 on the innermost and outermost peripheral sides smaller than the radial dimension δ3 of the vertical duct 3 in other parts, the innermost and outermost peripheral It becomes possible to reduce the flow rate of refrigerant flowing through the vertical duct 3 in the center, and increase the flow rate of refrigerant flowing through the vertical duct 3 in the center by that amount.

In other words, the flow rate of the refrigerant can be adjusted according to the amount of heat given to each vertical duct 3, and the temperature rise of the refrigerant in each vertical duct 3 can be equalized. As shown in FIG. 5, where the relationship between temperature and coil number is shown by taking the coil number on the horizontal axis, the temperature rise of each coil 4 can be made equal. Furthermore, since the temperature distribution of the winding 1 can be equalized without increasing the radial dimension of the entire winding 1, the number of coolers can be reduced and the current density can be increased by the reduction in temperature rise at the highest point. As a result, the entire stationary induction appliance can be downsized.

Note that the dimensions of the entire vertical duct 30 are such that, for example, if the vertical duct 3 at the periphery is made smaller than the conventional structure, the vertical duct 3 at the center is made thicker than the conventional structure, which reduces the overall refrigerant flow rate. You may set it to 11 to prevent this.

Furthermore, although this embodiment has been described in the case of a cylindrical winding, it goes without saying that the same can be applied to the case of a sheet winding.

〔Effect of the invention〕

As described above, the present invention allows the refrigerant to flow in accordance with the amount of heat given to each vertical duct, so that the temperature rise in each coil can be equalized. It is possible to obtain a winding structure for a stationary induction appliance that enables equalization.

[Brief explanation of drawings]

FIG. 1 is a vertical side view of an embodiment of the winding structure of a stationary induction electric appliance according to the present invention, FIG. FIG. 4 is a perspective view of a vertical duct of an embodiment of the winding structure of the stationary induction electric appliance of the present invention, and FIG. 5 is a radial temperature distribution diagram of the winding structure of the present invention. It is a distribution map. DESCRIPTION OF SYMBOLS 1... Cylindrical winding, 2... Inner insulating tube, 3... Vertical duct, 4... Coil (winding unit), 5... Vertical spacer, 6... Horizontal spacer, 7...・Horizontal duct,
9 Outer insulation cylinder, δl...Radial dimension of the vertical duct on the innermost and outermost periphery sides, δ2...-Radial dimension of the vertical ducts other than the innermost and outermost periphery sides.

Claims (1)

[Claims] 1. Winding units of a plurality of cylindrical windings or sheet windings that are wound in a concentric cylindrical shape via vertical spacers so as to form a plurality of vertical ducts in the radial direction on the outer circumference of the inner insulating cylinder, In a winding structure of a stationary induction appliance arranged between upper and lower horizontal spacers that communicate with a duct to form a horizontal duct at the upper and lower ends of the winding unit, the diameter of the vertical duct on the innermost and outermost sides. A winding structure for a stationary induction electric appliance, characterized in that the directional dimension is smaller than the radial dimension of the vertical duct in other parts.