JP2013243167A - Stationary induction apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a stationary induction apparatus which resolves a stream stagnation region occurring in a flow passage of a refrigerant for cooling winding and improves cooling performance.SOLUTION: A stationary induction apparatus comprises: a plurality pieces of disk-shaped winding 1 laminated and disposed; an insulator plate disposed between respective ones of the plurality pieces of winding 1 facing each other; and a plurality of duct pieces 3 disposed between the insulator plate and each of the winding 1. In a straight part 8 of each of the winding 1 and an inlet/outlet port 7 of a refrigerant 4, rectangular-shaped duct pieces 3a and parallelogram-shaped duct pieces 3b which have different plane shapes are obliquely disposed, and a refrigerant flow passage resolving a stream stagnation region is formed.

Description

  The present invention relates to a static inductor such as a transformer composed of a plurality of stacked disk-shaped windings, and more particularly to a cooling structure for windings.

  In general, a static inductor such as a transformer constituted by a disk-shaped winding secures a unit coil obtained by winding a flat wire or a round wire in a disk shape and a cooling medium flow path for cooling the winding. Insulating plates on which a large number of duct pieces are affixed are alternately stacked (see, for example, Patent Document 1).

FIG. 10 is a perspective view showing a schematic shape of the outer iron type transformer.
In FIG. 10, a winding 101 is configured by laminating a disk-shaped primary winding 101 a and a secondary winding 101 b, and an iron core 102 is provided outside the winding 101. In addition, although not shown, a tertiary winding may be employed depending on the application, and a horizontal arrangement rotated by 90 ° is also possible.

FIG. 11 is a cross-sectional view showing a single coil of the disk-like winding 101, and shows a cross section of a broken-line frame region A ′ in FIG.
In FIG. 11, a plurality of duct pieces 103 for forming a refrigerant flow path are disposed inside the winding 101. The plurality of duct pieces 103 all have a rectangular planar shape, and are arranged while being sandwiched at different intervals.

  In this type of static inductor, the temperature of the winding 101 must be suppressed to a certain temperature or less from the viewpoint of the heat resistance of the standard of the transformer and the insulating material used. 103 forms a refrigerant flow path for flowing in the refrigerant 104 (cooling oil or the like).

  The duct piece 103 is arranged in parallel to the flow 105 of the refrigerant 104 at the inlet / outlet 107 of the refrigerant 104, but the flow 105 of the refrigerant 104 is arranged at the straight portion 108 of the winding 1 other than the inlet / outlet 107. It is arranged vertically with respect to it.

In this case, a stagnation region 106 is generated in the flow 105 of the refrigerant 104, heat conductivity in the stagnation region 106 is deteriorated, and the temperature of the winding 101 is increased.
Specifically, the stagnation region 106 is considered to occur on the downstream side 106 a of the duct piece 103 and the inner peripheral side 106 b of the winding 101.

JP-A-9-134823 (paragraph 0012, FIG. 15, FIG. 20)

  In the conventional static inductor, the refrigerant flow path for suppressing the winding temperature is formed, but if a part of the winding has a high temperature due to the arrangement state of the duct piece, for example, Even if the winding temperature of the other part is low, it is necessary to suppress the winding temperature based on the high temperature part, so the cross-sectional area of the winding has to be set large as a whole. There was a problem that hindered weight reduction.

  The present invention has been made in order to solve the above-described problems, and in a static inductor constituted by a disk-shaped winding, the shape and arrangement of the duct piece are changed, and the conventional stagnation is achieved. By constructing the refrigerant so that it can also flow into the area (the wake side of the duct piece, the inner circumference side of the winding, etc.) Objective.

  A stationary inductor according to the present invention includes a plurality of disk-shaped windings arranged in layers, a plurality of insulating plates respectively disposed between the plurality of windings, a plurality of insulating plates, and a plurality of insulating plates A stationary inductor including a plurality of duct pieces disposed between the windings, wherein a plurality of duct pieces form a refrigerant flow path for cooling the plurality of windings. The piece includes a duct piece having a rectangular planar shape and a duct piece having a parallelogram planar shape, and is rectangular when an area radially inward of the opening that is the inlet / outlet of the refrigerant flow path is used as the inlet / outlet area. The duct pieces are arranged in the straight portions of the plurality of windings and the straight portion side region of the entrance / exit region, and are arranged so that the angles are different from each other with respect to the flow direction of the refrigerant flowing through the refrigerant flow path. A quadrilateral duct piece is a A tilt toward the side, in which is disposed in the linear region of the entrance area.

  According to the present invention, the parallelogram duct piece is arranged in the linear region of the refrigerant inlet / outlet so that the refrigerant flows toward the inner peripheral side of the winding, and alternate inclination angles are formed on the straight portions of the winding. By disposing the rectangular duct piece having the stagnation region that has occurred with respect to the flow of the refrigerant is eliminated, it is possible to suppress the occurrence of a local high temperature region in the disk-shaped winding, The cooling performance of the winding of the static inductor can be improved.

It is a perspective view which shows the stationary inductor which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the entrance / exit area | region of the refrigerant | coolant flow path by Embodiment 1 of this invention. It is a perspective view which shows the arrangement | positioning state of the insulating member by Embodiment 1 of this invention. It is sectional drawing which shows the cross-sectional shape of the insulating member by Embodiment 1 of this invention. It is sectional drawing which shows the unit coil by Embodiment 1 of this invention. It is explanatory drawing which shows the arrangement | positioning state of the duct piece in the entrance / exit of the refrigerant | coolant by Embodiment 1 of this invention. It is explanatory drawing which shows the inclination-angle of the rectangular duct piece by Embodiment 1 of this invention. It is explanatory drawing which shows the fluid resistance characteristic of the rectangular duct piece in Embodiment 1 of this invention compared with a conventional characteristic. It is a perspective view which shows the shape of the duct piece by Embodiment 2 of this invention. It is a perspective view which shows schematic shape of the conventional outer iron type transformer. It is sectional drawing which shows the single coil of the conventional coil | winding.

Embodiment 1 FIG.
FIG. 1 is a perspective view showing a stationary inductor according to Embodiment 1 of the present invention, and shows a schematic structure of a shell-type transformer as an example.
In FIG. 1, the outer iron type transformer includes a winding 1 and an iron core 2 provided outside the winding 1.

  The winding 1 is configured by laminating a disk-shaped primary winding 1a and a secondary winding 1b. Although not shown here, a horizontal placement by 90 ° rotation from the state of FIG. 1 is also possible, and a tertiary winding may be employed depending on the application.

FIG. 2 is an enlarged cross-sectional view showing the inlet / outlet region of the refrigerant flow path according to Embodiment 1 of the present invention, and shows a cross section taken along the broken-line frame region A in FIG.
In FIG. 2, the arrangement structure of the refrigerant flow path (duct piece 3) in the vicinity of the inlet / outlet 7 of the refrigerant 4 is shown.

In FIG. 2, a plurality of duct pieces 3 for forming a refrigerant flow path are disposed in the winding 1, and insulating members 9 and 10 are provided on the outer peripheral side surface and the inner peripheral portion of the winding 1. It has been.
The plurality of duct pieces 3 include a duct piece 3a having a rectangular planar shape and a duct piece 3b having a parallelogram planar shape, and each has not only a different planar shape but also an inclination angle (described later). The state is also different.

The rectangular duct piece 3 a is disposed in the straight portion 8 of the winding 1 and the straight portion side region 7 </ b> B in the region of the inlet / outlet 7 of the refrigerant 4.
On the other hand, the parallelogram-shaped duct piece 3 b is disposed in a linear region 7 A along the flow 5 of the refrigerant 4 in the region of the inlet / outlet 7 of the refrigerant 4.
In addition, the arrangement | positioning space | interval of each duct piece 3a, 3b is determined considering not only a cooling characteristic but an electromagnetic mechanical force and an insulation characteristic.

FIG. 3 is a perspective view showing an arrangement state of the insulating members 9 and 10.
In FIG. 3, the outer insulating member 9 is disposed in parallel to the flow 5 of the refrigerant 4, and the inner insulating member 10 is disposed along the inner periphery of the winding 1.

4 is a cross-sectional view taken along one-dot chain line BB in FIG. 3 and shows the cross-sectional shape of the insulating members 9 and 10. In FIG. 4, the insulating members 9, 10 have a U-shaped cross section.
As shown in FIG. 2 to FIG. 4, insulating members 9 and 10 having a U-shaped cross section are provided on the outer side surface and the inner end of the disk-shaped winding 1, and the refrigerant 4 is other than the winding 1. It is configured not to flow into unnecessary parts.

FIG. 5 is a cross-sectional view showing the unit coil 12 according to the first embodiment of the present invention, and shows an enlarged cross section of the one-dot chain line frame region C in FIG.
In FIG. 5, the unit coil 12 includes an insulating plate 11 disposed to face the winding 1 in addition to the duct piece 3 and the insulating members 9 and 10. The insulating plate 11 is disposed so as to sandwich the duct piece 3 and the insulating members 9 and 10 between the windings 1.

FIG. 6 is an explanatory view showing the arrangement state of the rectangular duct piece 3a in the straight portion 8 of the winding 1, and shows the arrangement state in the straight portion 8 (upstream side of the region of the inlet / outlet 7 of the refrigerant 4). Yes.
In FIG. 6, an opening (not shown) that is not covered with the insulating member 9 on the outer peripheral side of the winding 1 serves as the inlet / outlet 7 of the refrigerant 4.

FIG. 6 also shows a conventional arrangement state (broken line) for comparison with the arrangement state (solid line) of the duct piece 3a according to Embodiment 1 of the present invention.
As shown in FIG. 6, the rectangular duct piece 3 a is disposed so as to be reversed left and right for each pitch with respect to the direction of the flow 5 of the refrigerant 4.

FIG. 7 is an explanatory diagram showing an enlarged view of one of the upstream (rectangular) duct pieces 3a in FIG.
In FIG. 7, the rectangular duct piece 3a is rotated clockwise by an inclination angle θ around the mark “X” from the conventional (broken line) arrangement.

FIG. 8 is an explanatory diagram showing the fluid resistance characteristics of the rectangular duct piece 3a. The horizontal axis indicates the flow velocity, and the vertical axis indicates the fluid resistance.
In FIG. 8, the fluid resistance characteristic (broken line) according to the conventional arrangement state is also shown for comparison with the fluid resistance characteristic (solid line) according to the arrangement state of the first embodiment of the present invention.

  As shown in FIGS. 6 and 7, in the inlet / outlet port 7 of the refrigerant 4 and the straight portion 8 of the winding 1, first, a rectangle positioned in the straight portion 8 and the straight portion side region 7 </ b> B (upstream side) of the inlet / outlet port 7. The duct piece 3a (solid line) is inclined at an angle in the direction of the flow 5 of the refrigerant 4 from the center (see the x) from the state of being arranged perpendicular to the flow 5 of the refrigerant 4 (broken line). Rotated by θ.

In addition, in the direction of the flow 5 of the refrigerant 4 (downstream side), a rectangular duct piece 3a having an inclination angle of -θ (with the rotation direction reversed to the left and right with respect to the duct piece 3a) as illustrated. It arrange | positions so that it may mutually oppose.
In this way, a plurality of rectangular duct pieces 3 a having different angles are arranged in the direction of the flow 5 of the refrigerant 4.

That is, in the opening shown in FIG. 6, when the radially inner region of the winding 1 is an entrance / exit region, the straight portion 8 and the straight portion side region 7 </ b> B of the entrance / exit region have rectangular shapes. A duct piece 3a is provided.
On the other hand, a plurality of parallelogram-shaped duct pieces 3b (see FIG. 2) whose inclination is directed toward the inner peripheral side of the unit coil 12 are disposed in the linear region 7A on the entrance / exit 7 side region.

  2 and 6, the flow 5 of the refrigerant 4 flows along the rectangular duct piece 3a in the straight portion 8 and the straight portion side region 7B in the inlet / outlet 7 side region. The stagnation area downstream of the piece 3a is eliminated.

  In addition, the flow 5 of the refrigerant 4 in the linear region 7A on the entrance / exit 7 side region is inclined along the oblique side of the parallelogram duct piece 3b toward the inner peripheral side of the unit coil 12, The peripheral stagnation area is eliminated.

  Furthermore, the fluid resistance of the refrigerant flow path is a value obtained by adding resistance due to changes in the bend angle and expansion (reduction) of the flow path to the friction resistance determined by the cross-sectional area and length of the flow path. If the bending angle is large or the number of enlargements (reductions) increases, the fluid resistance increases. Therefore, in order to reduce the fluid resistance, it is necessary to make the bending angle gentle.

  For example, when a duct piece is disposed perpendicular to the refrigerant flow as in the conventional refrigerant flow path (FIG. 11), the refrigerant flows so as to largely bypass the duct piece, so the bend angle of the flow path is large. Therefore, the fluid resistance increases as shown by the broken line characteristics in FIG.

  On the other hand, according to the refrigerant flow path according to the first embodiment (FIGS. 2, 6, and 7) of the present invention, the bending angle of the refrigerant 4 becomes gentle, so that as shown by the solid line in FIG. The fluid resistance is reduced. As a result, the flow 5 of the refrigerant 4 becomes smooth, the flow rate increases, and the cooling effect of the winding 1 is improved.

  Accordingly, it is not necessary to set the entire cross-sectional area of the winding 1 to be large in order to suppress the temperature rise of the winding 1, and the winding 1 can be miniaturized, and the iron core 2 can be downsized accordingly. Can do.

  As described above, the stationary inductor according to the first embodiment (FIGS. 1 to 7) of the present invention includes a plurality of disk-shaped windings 1 and a plurality of windings 1 disposed between each other. Are provided with a plurality of insulating plates 11, and a plurality of duct pieces 3 provided between the plurality of insulating plates 11 and the plurality of windings 1. The planar shape includes a duct piece 3 a having a rectangular shape and a duct piece 3 b having a parallelogram in a planar shape, and forms a refrigerant flow path for cooling the plurality of windings 1.

The rectangular duct piece 3a has a straight portion 8 of the plurality of windings 1 and a straight portion side region 7B of the inlet / outlet region 7 when the radially inner region of the opening that is the inlet / outlet of the refrigerant flow path is used as the inlet / outlet region. Are arranged so as to have different angles with respect to the direction of the flow 5 of the refrigerant 4 flowing through the refrigerant flow path.
Specifically, the rectangular duct piece 3a is disposed so as to be horizontally reversed at every pitch with respect to the direction of the flow 5 of the refrigerant 4, and has an alternate inclination angle θ.

The parallelogram-shaped duct piece 3b has an inclination toward the inner peripheral side of the plurality of windings 1 in the opening serving as the inlet / outlet 7 of the refrigerant 4 and is disposed in the linear region 7A of the inlet / outlet region. Yes.
That is, the plurality of duct pieces 3 have different planar shapes in the straight region 7A of the inlet / outlet 7 of the refrigerant 4, the straight portion 8 and the straight portion side region 7B, and are inclined with respect to the direction of the flow 5 of the refrigerant 4 have.

As a result, the stagnation region is eliminated, and the refrigerant 4 is also applied to regions (such as the wake of the duct piece 3 or the inner peripheral side of the winding 1) that are likely to become high temperature due to deterioration of heat transfer in the disk-shaped winding 1. Since it can flow reliably, generation | occurrence | production of a local high temperature area | region can be suppressed, and the cooling capability of the coil | winding 1 can be strengthened.
Further, by suppressing the fluid resistance (see FIG. 8), it is possible to reduce the size of the stationary inductor.

Embodiment 2. FIG.
In the first embodiment, the duct piece 3a having a rectangular planar shape is used as it is, but a concave groove 13 may be formed at the center of the duct piece 3a as shown in FIG.
FIG. 9 is a perspective view showing an arrangement state of the rectangular duct piece 3a according to the second embodiment of the present invention, and shows an arrangement relationship with respect to the flow 5 of the refrigerant 4 and the insulating members 9, 10. FIG.

In FIG. 9, the plurality of duct pieces 3 are arranged in the same manner as described above (FIG. 2).
In this case, a concave groove 13 is formed in the rectangular duct piece 3a on the contact surface side with the winding 1 along the direction 5 of the refrigerant flow.

As shown in FIG. 9, by forming the concave groove 13 on the winding 1 side of the duct piece 3, the refrigerant 4 flows through the concave groove 13, and the winding 1 and the refrigerant 4 are in good contact. Therefore, the substantial heat transfer area increases.
Although not shown here, the same effect can be obtained by forming the concave groove 13 not only in the rectangular duct piece 3a but also in the parallelogram duct piece 3b. it can.

  As described above, the plurality of duct pieces 3 according to Embodiment 2 (FIG. 9) of the present invention have the concave grooves 13 formed on the contact surface side with the plurality of windings 1. Has a shape along the direction of the flow 5 of the refrigerant 4, so that the heat transfer area can be further increased without changing the arrangement state of the plurality of duct pieces 3 from the state described above (FIG. 2). There is.

  1 winding, 1a primary winding, 1b secondary winding, 2 iron core, 3 duct piece, 3a rectangular duct piece, 3b parallelogram duct piece, 4 refrigerant, 5 refrigerant flow, 7 inlet / outlet, 7A straight line Region, 7B Straight portion side region, 8 Straight portion, 9, 10 Insulating member, 11 Insulating plate, 12 Unit coil, 13 Recessed groove θ Inclination angle.

Claims (3)

A plurality of disk-shaped windings arranged in layers;
A plurality of insulating plates respectively disposed between the plurality of windings;
A plurality of duct pieces disposed between the plurality of insulating plates and the plurality of windings,
A stationary inductor in which a refrigerant flow path for cooling the plurality of windings is formed by the plurality of duct pieces,
The plurality of duct pieces include a duct piece having a rectangular planar shape and a duct piece having a parallelogram planar shape,
When the area inside the opening in the radial direction of the opening that is the entrance / exit of the refrigerant flow path is the entrance / exit area,
The rectangular duct pieces are arranged in the straight portions of the plurality of windings and the straight portion side region of the entrance / exit region, and have different angles with respect to the flow direction of the refrigerant flowing through the refrigerant flow path. Arranged,
The parallelogram duct piece has an inclination toward the inner peripheral side of the plurality of windings and is disposed in a straight line region of the entrance / exit region.   The stationary inductor according to claim 1, wherein the rectangular duct piece is disposed so as to be reversed left and right for each pitch with respect to a flow direction of the refrigerant. The plurality of duct pieces have concave grooves formed on a contact surface side with the plurality of windings,
The stationary inductor according to claim 1, wherein the concave groove has a shape along a flow direction of the refrigerant.

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