DE1921862A1 - Isolation disc element for supporting disc coils - Google Patents

Description

Augsburg, April 28, 1969

Westinghouse Electric Corporation, J5 Gateway Center, Pittsburgh, Pennsylvania, United States of America

Isolation disc element to support disc coils

The invention relates to electrical devices with induction windings, such as transformers or reactors of the boiler type, and in particular an insulating disk element for supporting disk coils of electrical windings, with a plate part which has insulating projections resting on the turns of an adjacent disc coil.

. In such electrical equipment is known _c to build up one or more of the windings of a number of series-connected flat coils. The disc coils lie next to one another at a certain distance and are separated from one another by insulating disc elements. The latter included

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each a plate part made of insulating material, an .- ~. which by means of an adhesive a large number of rectangular ones. Isolation blocks attached 1st. The side of the plate. · ■■ -. The part to which the insulation blocks are attached faces a disc coil, the insulation blocks resting against the windings of the disc coil. The plate part made of insulating material and the opposite end face · ■ -. the disc coil form a cooling channel through which: ■ an insulating coolant, such as oil, can be passed. The rectangular insulating blocks are used to keep the spacing between the disc coil and the insulating plate part and form a multitude of flow paths through which the coolant flows In addition, the insulating blocks support the windings of the disk coil and prevent their deformation when dynamic short-circuit forces occur.

Placing and gluing the rectangular "-blocks on the insulating plate part · is, however, 'with -the - :."·'.' known insulation disc elements time-consuming and cost-c <Ic playful. The arrangement-of-the-insulation-blocks is not only involved, but different arrangement-patterns must also be used in the curved corner areas of the insulation-disc elements than in the straight sections which connect to the corners % ' ^: weiät'zwo "ii".Be-' ^h border lines between different Änordhungsramstern .auf | -; ■>. namely three at each ^; corner "The arrangement'der Isolafciohsblocks

at the boundary lines, the workers remain in production left, the transition between the arrangement patterns also changing with the size of the disc elements.

Particular care must be used in the arrangement of the rectangular Isolationsblöeke near the edges of the disc member, since the insulation blocks must not come with channel-like insulating parts in conflict here, which are disposed inside and outside of the disc coil to the curved g and straight edge portions. If it turns out during assembly that a channel-shaped edge insulation linefc and an insulation block interfere, where this disturbance is eliminated by removing the insulation block in question. Since it is difficult to replace this insulation block with an IsoXafclons block of smaller dimensions, since it is hardly possible to insert such a smaller insulation block between the disk element and the disk coil after assembly, the removed insulation blocks are often no longer replaced at all, so that one behaves - | nism moderately large area of the disc coil remains without support.

The rectangular insulation blocks generally cover 45 # to 55 # of the disc coil area, so it is necessary to the heat loss from the coil over the remaining area to dissipate. Tests have shown that the rectangular IsolationsblSeke tend to distribute the oil flow unevenly,

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so that a certain part of the oil is in relatively straight line running paths flows and suffers only little turbulence and therefore absorbs very little heat, while others • Oil quantities in other areas have a low flow velocity maintained. In this way, undesirable hot spots arise in the coil, which reduce the overload capacity of the limit the device in question.

The object is to be achieved by the invention, a To create insulation washer element, which reduces the overload capacity of the winding of an electrical device in mechanical and increased in thermal terms and at the same time the manufacture of the disk element and the assembly of the relevant winding simplified.

The invention is based on an insulating pane element for supporting disc coils made of electrical windings, with a plate part which is attached to the turns of an adjacent Has disc coil abutting insulation projections.

The stated object is achieved in that this on At least one side of the plate part arranged insulation projections with respect to the plane of the plate part triangular Have shape.

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The triangular insulation projections expediently each place a flow path between each plate part and an adjacent disc coil through which a coolant for cooling one of at least one disc coil built-up winding of an electrical device can be passed through is.

The triangular insulation protrusions or insulation blocks each cover a smaller area of the disc coils than { the rectangular insulation blocks, without thereby undermining the property of the insulating disk element, the disk coil To support short-circuit stress sufficiently, is impaired, so that a larger exposed coil on the disc coil Space is available for cooling.

Preferably, the isolation protrusions become uniform arranged so that a uniform coolant flow over the exposed disc coil surface and hot spots and areas where the coolant is still, be avoided.

In the following, the invention is illustrated by the description of Implementation examples with reference to the enclosed Drawings explained in more detail. In these drawings show:

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Pig. 1 is a sectional view of a transformer whose winding is constructed in the manner according to the invention, _-. _: .

2 shows a perspective view of part of an insulating pane element according to the invention "■■■ -" ·. - "- ■ -..-. ■■

Figure 3 is a view of part of another

Embodiment of the insulation pane element according to the invention,

4 to 7 top views of the isolation spacer blocks

for other embodiments of the invention.

1 of the drawings shows an electrical device 10 equipped with induction windings, which can be a transformer or a choke coil and has a winding 12 which is arranged in a tank 14 which is insulated up to a height 17. Coolant -, - is filled with oil, for example. The boiler 14 has inlet connections IS and outlet connections 20 which are connected to an external heat exchanger (not shown) so that the insulating coolant can be circulated and cooled. The insulation coolant is heated by - the winding 12 'and the core: · and: rises, so that a natural upward flow of the' coolant "" results by convexion, as in KLg ^. 1 of the drawings. . ■ is indicated by arrows - To generate a forced circulation of the coolant, additional pumps z · -:

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be provided, which the coolant, if necessary, through the winding 12 and through the external heat exchanger support financially.

The arrangement formed from the core and the winding corresponds to the jacket design and can be single-phase or multi-phase. The arrangement 12 contains magnetic core sections 22 raid 24, which are made up of a plurality of superposed magnetic blocks 26, which in turn are made of a suitable magnetic material, for example grain-oriented silicon steel. The core sections 22 and 24 lie next to one another, with their adjacent parts forming a winding-carrying leg for the winding arrangement. The arrangement 12 also has a winding, generally designated 30, which is inductively coupled to the core sections 22 and 2%. If the device 10 xm is a transformer, the winding contains a high-voltage part and a low-voltage part, which can be isolated from one another or operated in an economy circuit.

The electrical winding 30 consists of a multiplicity of disc washers, each of which consists of spiral windings are constructed, as is the case, for example, for the disc coil 32 is shown, which has an opening 34 for receiving the legs the core sections 22 and 24 has. The disc coils

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are piled up side by side, with their windows or align openings. Each belonging to one of the windings Disk coils are generally known by connecting their beginnings or their ends in series switched.

As already indicated, each of the disc coils, for example also the disc coil J> 2, is made up of several wind-

• fertilize 36 from an insulated electrical conductor, both -

for example made of copper or aluminum, the conductor consisting of one or more conductor strands depending on the application in question. Each disc coil has two opposing main surfaces which are oriented perpendicular to the opening or the windows Jk and which are delimited by the inner edge surrounding the opening and by the outer edges of the coil. As can be seen from the drawings, the disc coils are essentially rectangular in shape and have four straight

~ cuts to which four rounded corner areas meet connect.

On the outer edge and on the inner edge of each disc coil are several tightly fitting, channel-shaped insulation surround pieces arranged to isolate and accommodate the hotien Electric field strengths in the edge area each serve a coil. For example, the disc coil 30 with a number of channel

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shaped insulation surrounds 38 provided with Their ends are attached to each other on the inner edge of the coil in such a way that they completely cover this edge, and in a corresponding manner, channel-shaped insulation border pieces are also provided on the outer edge of the disc coil 40 attached, which completely cover the outer edge.

Cooling gj are adjacent to the main surfaces of each disc coil channels, which are formed by means of insulation washer elements, the a plurality of insulation spacer blocks wear, each of which has a surface in contact with a main surface of a disc coil. It means that a surface of the insulation blocks in each case rests against the conductor turns 36 of the respective disk blocks, while the opposite surface of the insulation block in question is attached to an insulation plate part, the Shape essentially with the shape of the disc coil

f matches. ^

In detail, the main surface 42 of the pancake coil 32 is cooled by a cooling channel, which by means of a Soheibenelementes 4j5 is formed, which a plurality of Has spacer blocks 44 which are attached to an insulation plate element 44, for example by gluing. The insulation block 44 and the insulation plate part 46

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can be made of any suitable insulation material, for example from pressboard. *

The next target coil adjoining the target coil j52, which is located in the cut-open part of the device shown in Fig. 1, is via an insulating disk element 49 channel formed is cooled. This disk element consists of the insulation plate part 48 and a plurality of insulation blocks or spacer blocks 50. The insulation blocks 50 are on a main surface of the insulation plate part 48 glued, while the other main surface of this plate part of that main surface of the insulation plate part 46 is facing, which is not provided with insulation blocks. According to another embodiment of the invention can instead of the two insulation disk elements, each resting against one another with a main surface, which on the remaining, free main surfaces are provided with insulation blocks, a single insulation disk element is used which has a single insulating plate part, on "its two opposing main surfaces in each case a variety of spacing isolation blocks is attached.

According to the invention, the spacing is used Isolation blocks 44 and 50 are triangular in shape and are arranged in a uniform pattern. As shown in Fig. 2

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1 of the drawings, the triangular insulation blocks 50 can have the shape of equilateral triangles which are arranged in vertical, horizontal or diagonal rows. All triangular isolation blocks are aligned in the same way. The insulation blocks 50 are at the same distance from one another, the distance between the surface centers of adjacent insulation blocks being the same. If, as indicated by M dash-dotted circular lines, a circle is drawn around a center of gravity or the center of the surface of an insulation block, then this circle intersects all of the center points of the surface of the immediately adjacent insulation blocks. In other words, this means that the insulation blocks are offset vertically from row to row, the insulation blocks being aligned with the next but one vertical rows in the horizontal direction and the insulation blocks in the vertical rows in between are also each horizontally aligned with one another. The centers of gravity or area centers of the isolation blocks in a row of horizontally aligned blocks lie on an imaginary line, which in turn is located in the middle between the respective corresponding line above and the corresponding line below.

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It has been found to be the most effective. Cooling is achieved when the isolation block 50 be arranged in such a way that the directed KühlmitteIstrom impinges on one side of the insulation blocks essentially perpendicular. As in Fig. of the drawings is indicated by arrows, the coolant flow thus hits that side of the insulation blocks which is perpendicular to the upward flow of the coolant is aligned, so for example on the side 5 ^ of the block 52, creating turbulence becomes and a swirl takes place, which leads to a very effective transfer of heat from the coil surface to the coolant. After hitting the vertical On the sides of the insulation blocks, the coolant flow is divided into different flow paths so that the im Flow path lying insulation blocks are flowed around.

Another important consideration when arranging the insulation blocks is the choice of the spaces between them. If the spaces between them are too large, straight lines are created between the vertical rows of insulation blocks running vertical flow paths. In this case, most of the coolant would be along these flow paths and only a very small flow of coolant would get under the insulation blocks. This is very undesirable because it is hot in the areas of reduced coolant flow

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There are no spots and the too little turbulence of the flow in the vertical flow paths just traversed enables very effective heat transfer. However, the insulation blocks must not be moved too close together, so that they do not obstruct the flow path of the coolant. It has been found that when using triangular insulation blocks with a side length of approximately 5 cm an overlap between the rows of about 5 * 5 mm to 6.5 mm is appropriate. This overlap is indicated in Fig. 2 of the drawings and is chosen to be the same in all directions. This is achieved in that the mutual spacing between the insulation blocks in the vertical rows is the same the distance between the insulation blocks in the corresponding adjacent diagonal rows is chosen. The tips of each triangular insulation blocks point to the center of the corresponding side of the respective adjacent insulation block 10. The Distance between the tips of the insulation blocks and the sides of the adjacent insulation blocks which lie opposite these tips so is uniform. This distance between the insulation blocks is determined by initially the desired overlap between the vertical rows is determined, after which the distance between the tips of the insulation blocks and the immediately adjacent sides of other insulation blocks between the vertical rows. This distance is then used to determine the distance between the insulation blocks in the vertical rows. the The overlap can be seen by drawing straight lines

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be made, each parallel to the sides of the triangular insulation blocks through all of the same Go corners of the triangular blocks in a row. For example, the dashed line 56 for the first vertical Row of blocks are drawn, which is perpendicular to the lower sides of these blocks and the lower connecting the right corners of the insulation blocks. Furthermore, the dashed line 58 in the second vertical Row of blocks are drawn. This line is perpendicular to the lower sides of the insulation blocks and cuts the lower left corners of the insulation blocks in the second vertical row. The distance 60 between the lines 56 and 58 indicate the overlap between adjacent vertical rows of insulation blocks. In a similar way the dashed lines 62 and 64 can be drawn in, which run perpendicular to the respective left-hand sides of the insulation blocks and the respective upper corners of the insulation blocks of a diagonal row or the lower left-hand sides Cut the corners of the insulation blocks of the next diagonal row above, creating an overlap distance is indicated between those diagonal rows that of top left to bottom right, this overlap section having the same dimension as the overlap section 60 has. Finally, lines 68 and 70 can also be drawn in which run perpendicular to the right-hand sides of the insulation blocks and the upper corners of the

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Cut insulation blocks of a diagonal row or the lower right corners of the insulation blocks in the next higher diagonal row, which indicates an overlap section 72 between those diagonal rows of insulation blocks which run from the bottom left to the top right, this overlap section being exactly as large again, like overlaps 60 and 66.

The overlaps provided between the vertical rows and between the diagonal rows interrupt the straight flow paths and form curved flow paths for the coolant, which is always guided in such a way that it meets those sides of the triangular insulation blocks that are perpendicular to the upward flow of coolant are. This will put under each triangular isolation block a turbulence is generated in a similar manner in each case.

The importance of the alignment of the isolation blocks can be illustrated by assuming that the coolant flow opposite to the flow indicated by the arrows in FIG. 2. The coolant would never impinge perpendicularly on an insulation block side surface, but only along the sides the insulation blocks flow. Only a very weak one would come Coolant flow along those sides of the insulation blocks which are parallel to the side 5 ^ of the insulation block 52.

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It is therefore essential that the three- _; angular blocks are oriented so that one side of each block is oriented substantially perpendicular to the upward flow of coolant so that that side is hit substantially perpendicularly by the coolant flow, and it is also important that the blocks with respect to the vertical rows of Row to row are offset in the vertical direction so that an overlap between the rows is possible, through which the coolant is also fed to those sides of the insulation blocks which are perpendicular to the direction of the coolant flow.

An insulating disk element according to the invention was made by making triangular insulating blocks Pressboard were used, the dimensions of which were chosen so that their side length 5 cm and their thickness 6.25 mm fraud. The Isolatiohsblocks were glued to a plate part, which is made of pressboard in a thickness of about 3 mm existed. The distance between the geometric centers of the triangular insulation blocks was 5 cm and the overlap 6 mm was chosen between the vertical and diagonal rows. About the upward triangular insulation blocks a transparent cover plate was placed, which simulated the effect of a disc coil, and a colored coolant was passed through the flow channel thus formed so that 'the

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Coolant hit one side of each insulation block substantially perpendicularly. It turned out to be around all sides of the isolation blocks a uniform coolant flow came about.

For comparison, an insulating disk element of a previously known type was produced, with rectangular spacer blocks being attached in a known arrangement and again a transparent cover plate being placed over the upwardly projecting rectangular spacer blocks. Then, a colored coolant was passed through the channel thus formed. The result here was that very specific flow paths were being formed and approximately 50% of the exposed surface of the coil would not have been adequately cooled. The main part of the coolant flow ran in these specific flow paths without significant turbulence, the coolant standing still in the areas outside the flow paths mentioned. Since approximately K5% to 55 $ of the coil surface is covered by the spacer blocks when using rectangular spacer blocks, this means that only about 25 $ of the coil surface is sufficiently cooled, since an effective coolant flow is only achieved in 50 # of the exposed coil surface. When using triangular spacer blocks, on the other hand, only 40 # to 4l # of the coil surface are covered by spacer blocks and essentially the entire exposed coil surface is well cooled.

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The reduction in percentage achieved over the ratios for known rectangular spacer blocks however, the coil surface covered by triangular insulation blocks does not set the support properties of the insulating disk element with regard to the support of the coil windings in the event of short-circuit stress. The uniformly distributed triangular insulation blocks support the coil turns evenly without it it can happen that certain 3 coil areas are not supported, as is the case when arranging rectangular insulation blocks can occur due to incorrect work in production or how this is the pail if due to a Interference with the grooved insulation edging pieces, insulation blocks must be removed. In the case of the uniform Arrangement of the insulation blocks it is possible to print the arrangement pattern on the insulation plate part, wherein the pattern of the arrangement of the groove-shaped insulation skirting pieces on the reel edges takes into account.

As shown in Figure 2 of the drawings, the insulation blocks 50 are formed by "individual block parts" which is attached to the insulation plate part 46 by means of a suitable adhesive or glue, for example will. Instead of using individual blocks 50, however, triangular projections can also be provided, which is integrally connected to the insulation plate part 46

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are. The protrusions can either extend outwardly from a back plate of uniform thickness, or they can be formed in one piece by pressing the insulating plate between suitable molds, as long as the insulating material is in a semi-plastic state. This can either be done during manufacture of the pressboard happen or the pressboard can subsequently be softened by a softening process, which by Immersing the insulation board in water prior to molding can be done.

Another option for attaching the triangular spacer and / or insulation blocks to an insulating plate is shown in Fig. 3 of the drawings, which is part of an insulating disk element according to the invention shows in elevation. The insulating disk element 80 has a plate part 82 and made of insulating material a variety of triangular spacer and isolation blocks. Instead, however, the blocks 84 directly on the insulating plate part 82, the blocks 84 are glued to thin strips of insulating material beforehand, glued onto strips 86, 88 and 90, for example. The triangular insulation blocks can be glued onto the thin insulation strips automatically, with the spacer insulation blocks are expediently automatically glued to the strip immediately during their production. To the

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The insulation strips 86, 88 and 90 either in width less than the side length the triangular insulation blocks or the strips can be serrated in the manner shown in FIG. 5 of the drawings. The strips provided with a serrated profile have the advantage that a automatic alignment of the insulation blocks from row to row is achieved and the required displacement between the rows results in a simple manner in that the serrated profiles of the strips are placed against one another. The strips 86, 88 and 90 are then converted into corresponding Length pieces cut and placed on the isolation plate part 82 glued on.

While spacer isolation blocks are used in the preferred embodiment of the invention, which have the shape of equilateral triangles, it is understood that the invention also includes insulating projections which are substantially triangular in shape, d. H. have three outer corners. For example, Pig. 4 of the drawings a spacer isolation block 94, both sides 95 and 96 of the same length as each other, but shorter than the side. The isolation blocks can therefore be equilateral triangles the oil flow is directed towards the side 97, as indicated in Fig. 4 by arrows.

ORiGt ^ AL INSPECTED

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To reduce the coil surface area covered by the insulation blocks and to enlarge it The area of the coil from which heat can be dissipated can be the triangular insulation blocks with cutouts be provided, which reduce their area without their effectiveness in supporting the coil turns is deteriorated under short-circuit stress. For example, FIG. 5 of the drawings shows a block 100, which has a triangular cutout 102 on that side which faces the cooling oil flow indicated by arrows, so that the direction of oil flow is essentially vertical side carries the neckline. This cut out area of the spacer block creates an even greater turbulence in the oil flow.

Figure 6 of the drawings shows a standoff isolation block 104, which is triangular on both of its sides, which are inclined to the general direction of flow of the cooling oil Has cutouts 106 and 108, and finally Fig. 7 of the drawings shows a standoff isolation block 110 indicating has triangular cutouts 112 or 114 or 116 on all three sides.

Expedient, essentially triangular spacer blocks according to the invention also result when one or more sides of the triangular spacer blocks are concave or convex \ s & di

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In summary, it can be stated that through the Invention the possibility for a new and improved winding structure is created, which disc coils and contains insulating washer elements located therebetween, the latter being a mechanical support for the turns of the disc coils and with the opposite coil surface to form a cooling channel Train dissipation of the heat loss from the coils. The insulating pane elements have an insulating material existing plate part, from the at least one side of which protrude a plurality of triangular projections, which are arranged in a certain pattern, which on the one hand provides the necessary mechanical support for the coil windings results and on the other hand covers the coil surface to a lesser extent than known insulating disk elements. The triangular, spacing-apart insulation protrusions also improve the cooling of the coils quite significant compared to arrangements with known rectangular spacer blocks. Hot spots on the coils are avoided when using triangular spacer blocks or spacer protrusions, which is essentially a uniform flow of the coolant over the free coil surface and on the turbulence of the coolant flow is based when the coolant moves the tortuous flow paths formed by the triangular insulation blocks flows through. In addition to an improvement in cooling

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the coils are used to manufacture the insulating disk elements simplified, since only a single pattern for arranging the spacer blocks is required for each disc element is. The arrangement pattern of the spacer blocks is based on the center line of the insulating disk elements and is made by the respective size of the disc elements is not affected. Further only a single block size is required. the The uniformity of the pattern and the uniformity of the block size facilitate automation when laying an insulation panel part with spacer insulation blocks and also enables the blocks to be glued on beforehand thin insulation strips, which are subsequently placed on an insulation plate part be glued. Finally, the insulation blocks can also take the form of one-piece molded on Have projections which protrude from at least one side of an insulation plate part. Shall the triangular ones Isolation blocks are placed on the isolation plate part by hand, so the arrangement pattern on the plate part be preprinted so that the arrangement is more time-saving and errors in the arrangement are avoided.

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Claims (9)

19 ^ 1862 Patent claims: Isolation disc element to support disc coils electrical windings, with a plate part which rests against the turns of an adjacent disc coil Has insulation projections, characterized in that they are on at least one side of the plate part (46 or 82) arranged insulation projections (50 or 84 or 94 or 100 or 104 or 110) with reference to the plane of the plate part have a triangular shape. 2. Ieolations disk element according to claim 1, characterized in that the triangular DAFL insulating projections (50 or 84 or 94 or 100 or 104 or 110) Jewell "(BXW 46th 82) a Strömungepfad between each plate portion and a Define adjacent disc coil (32) through which a coolant for cooling a winding of an electrical device made up of at least one disc coil can be passed. 3 «insulating pane element according to claim 1 or 2, characterized characterized in that the isolation protrusions are made in one piece are connected to the plate part. 4. Ißolations disc element according to claim 1 or 2, characterized in that the IsolationsvorsprUnge (50 or 84 - 24 - BAD ORiGIMAL 909847/0578 or 94 or 100 or 104 or 110) of individual triangular Blocks are formed which are each attached to the plate part (46 and 82). 5. Insulating pane element according to one of Claims 1 to 4, characterized in that the triangular insulating projections (50) are essentially triangular in shape at the same time. . 6. Isolation disc element according to one of claims 1 to 5 » characterized« in that the isolation projections (50 or 84 or 94 or 100 or 104 or 110) are arranged in rows on the plate part (l6 or 82) and that the central point of each insulation projection is at the same distance from the central point of the respective adjacent insulation projection (FIGS. 1 to 3). 7. insulating disk element according to claim 6, characterized marked «that the triangular insulating projections (50 or 84 or 94 or« 100 or 104 and 110) are offset from one another «with the sockets of the insulating projections of a row moving around a certain one Line Via the line connecting the corresponding corners of the Isolation projections of the respective adjacent row extend out "so that a broken flow path between each adjacent rows of insulating projections results (Figure 2). - 25 - ORIGINAL BATHROOM 9 09847/0576 ■ ι ? · H 6 2 8. Isolation disc element according to claim 2 and one of claims 3 to ^r {, characterized in that the triangular isolation '/ ürspr; e (50 or 84 or. 9 ^ or 100 or 104 or. 110) in the flow of the coolant in such a way that this in each case essentially perpendicularly meets a triangular side of each insulation projection. ORIGINAL BATHROOM - 26 - 909847/0 5 76