JPH09232164A - Triangularly arranged tripod-core type three-phase transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a triangularly arranged tripod core type three-phase transformer beneficial in respect of transportation and having a high mechanical strength, by balancing three-phase magnetic paths, lowering the height of the iron core and reducing a floor space occupied, and reducing the iron core noise. SOLUTION: The center of the axes of three iron core legs formed by putting opposite to each other and joining by an angle of 60 degrees two sets of blocks obtained by piling up a plurality of stages of unit blocks by n stages, obtained by laminating magnetic steel sheets of required width so as to have a cross section in the shape of a parallelogram having acute angles of 60 degrees and obtuse angles of 120 degrees at each unit block, and piling them up so that its external tangent line may be circular, is arranged at the apex of an equilateral triangle so as to stand side by side mutually. The upper and lower parts of each of these three iron core legs 2 are joined, arranging each two yokes 3 so as to form an angle of 60 degrees between them formed by piling up a plurality of unit blocks by n stages obtained by laminating magnetic steel plates of require width so that their longitudinal-direction both ends to be joined parts with the iron core legs 2 may be arranged to make the angle between the direction of length and that of lamination 60 degrees.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an iron core of a three-phase transformer, and more particularly to a structure of a tripod iron core having a triangular arrangement of laminated cores.

[0002]

2. Description of the Related Art Iron cores of an inner iron type three-phase transformer include a tripod core and a pentapod core. All are made of iron core legs with windings fitted and yokes that connect the iron core legs.
The tripod core is often used in the three phases. The three-phase five-leg iron core has a smaller amount of magnetic flux passing through the yoke due to the amount of magnetic flux of the iron core leg, so the cross-sectional area of the yoke can be reduced and the width of the yoke is reduced, so the overall height of the iron core is low. Become. For this reason, the five-leg iron core is used in large capacity transformers, etc., where it is necessary to reduce the height of the iron core due to transportation size restrictions.

As the magnetic steel sheet, a grain-oriented silicon steel sheet or a non-oriented silicon steel sheet is used. As a method of stacking steel plates, there are a strip shape in which rectangular steel plates are combined and a frame shape in which the joint end between the core leg and the yoke is 45 degrees.
Since the grain-oriented silicon steel sheet has excellent magnetic properties in the rolling direction, it has a frame shape so that magnetic flux can pass in the rolling direction at the joint between the iron core leg and the yoke.

The connection method in which the joints of the steel plates of the iron core legs and the steel plates of the yokes are alternately overlapped one by one or several by one is called lap connection.

FIG. 12 is a perspective view of a tripod iron core of a conventional three-phase transformer, and FIG. 13 is a plan view thereof. As shown in FIGS. 12 and 13, a three-iron core leg 32 ( tripod)
The upper yoke 33 and the lower yoke 33 are arranged on a plane to form the iron core 34. In this case, the method of stacking the steel plates is a frame shape in which the joint end between the iron core leg and the yoke is 45 degrees.

[0006]

In the tripod core of the three-phase transformer described in the prior art, since the iron core legs 32 are arranged in a plane, the magnetic paths are geometrically different between the left and right and the center. Come on. Therefore, the exciting current flowing in the winding of the center leg is different from the exciting current flowing in the winding of the left outer leg and the winding of the right outer leg. It had a problem that it has become.

The present invention has been made in view of the above problems of the prior art, and balances the three-phase magnetic paths,
An object of the present invention is to provide a triangular tripod core type three-phase transformer that has a low iron core height and a small installation area, reduces iron core noise, is advantageous in transportation, and has high mechanical strength.

[0008]

Means for Solving the Problems In the present invention, means for solving the above-mentioned problems are as follows: a magnetic steel sheet having a required width is used, and the cross-section has an acute angle of 60 degrees and an obtuse angle of 1
Three blocks formed by stacking multiple sets of unit blocks stacked in a parallelogram shape of 20 degrees, butting together two sets of blocks and joining them at an angle of 60 degrees so that their tangent lines are circular. The cores of the iron core legs are arranged so as to be parallel to each other by arranging the centers of the axes of the iron core legs at the vertices of an equilateral triangle. Yokes formed by stacking a plurality of stages of unit blocks in which both ends in the length direction that are joints with the iron core legs are stacked at an angle of 60 degrees in the length direction and the stacking direction,
By arranging and joining each two yokes at an angle of 60 degrees, the three-phase magnetic paths are balanced, the height of the iron core is lowered, the installation area is reduced, and the iron core noise is reduced. It is a three-phase transformer that is advantageous in transportation and has high mechanical strength.

When a grain-oriented silicon steel sheet or a non-oriented silicon steel sheet is used as the magnetic steel sheet, the joint portion of the unit blocks of each stage of the core leg and the yoke is zigzag right and left at an angle of 30 degrees with respect to the center line. Are arranged so that they are butt-joined with each other at a line intersecting with each other, and the long sides of the trapezoids of the unit blocks at each stage of the iron core legs are butted against each other, and the faces of these two trapezoidal unit blocks are formed into a V shape with 60 degrees open. The hypotenuses of the trapezoidal unit blocks of each stage of the iron core leg are joined to the hypotenuses of the tips of the unit blocks of each step of the yoke.

Further, the joining positions of the silicon steel plates of the unit blocks of each stage of the iron core leg and the yoke are alternately moved at a predetermined fixed interval for each silicon steel plate, and every other one is laminated at the same position alternately. Either the stacking structure or the step lap stacking structure in which the joining positions of the iron core leg and the silicon steel plate of the yoke are sequentially moved at a predetermined fixed interval for each silicon alternation and laminated at a plurality of joining positions .

When a non-oriented silicon steel sheet is used as the magnetic steel sheet, the joining portion of each stage of the iron core leg and the yoke is constructed by alternately stacking strip-shaped non-oriented silicon steel sheets in an L-shape. Often.

Further, the magnetic noise is injected into the gap between the left and right zigzag iron core legs and the yoke butts and hardened to fill the gap, whereby the core noise of the three-phase tripod transformer is reduced. Can be reduced.

In this way, the three iron core legs of the three-phase transformer are arranged in such a manner that the axes of the three iron core legs are arranged at the apexes of an equilateral triangle so as to be juxtaposed to each other. By joining the unit blocks of each stage at an angle of 60 degrees to form a new structure of the part where the iron core is laminated, the three-phase magnetic path is balanced, the height of the iron core is reduced, and the installation area is reduced. It is a three-phase transformer that reduces iron core noise, is advantageous in transportation, and has high mechanical strength.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings.

FIG. 1 is a perspective view showing the shape of an iron core of an embodiment of a triangularly arranged tripod core type three-phase transformer of the present invention, and FIG. 2 is a plan view thereof, as shown in FIGS. The centers of the axes of the three iron core legs 2 (tripods) around which the wire 1 is wound are arranged at the vertices of an equilateral triangle, and are arranged so as to be in parallel with each other.
The upper and lower sides of each of these three iron core legs 2 are joined by a yoke 3 to form a magnetic path to form a triangular tripod iron core 4.

FIG. 3 is a plan view showing the joint portion of the yoke of the embodiment of the triangularly arranged tripod core type three-phase transformer of the present invention.
As shown in FIG. 5, approximately half of the iron core legs 2 are stacked in two directions inside the insulating cylinder 5 which is the innermost side of the winding, with each half having a V shape of 60 degrees. In this case, a magnetic steel plate having a required width is used for each unit block with an acute angle of 60 degrees in the cross section.
The two sets of blocks in which n stages of a plurality of stages of unit blocks D ₁ , D ₂ , ... D _k , ... D _n stacked in a balanced quadrilateral with an obtuse angle of 120 degrees are acute angle parts of 60 degrees Butt and join at an angle of 60 degrees, and the center of the axis of the three iron core legs 2 formed by stacking them so that their tangents are circular, as shown in FIG. They are arranged so as to be in parallel with each other. Note that K ₁ indicates the inside and K ₂ indicates the outside.

The upper and lower portions of each of these three iron core legs 2 are joined together by magnetic steel plates having a required width, and both ends in the length direction that form a joint with the iron core legs form an angle between the length direction and the laminating direction. A plurality of unit blocks D ₁ , D ₂ ,
The yokes 3 formed by stacking n stages of D _k , ... D _n are arranged by joining each two yokes 3 at an angle of 60 degrees.

FIG. 4 is an enlarged plan view showing the D _k stage of the iron core of the embodiment of the triangularly arranged tripod core type three-phase transformer of the present invention.
As shown in FIG. 4, the iron core leg 2 or the yoke 3 is divided in the stacking direction into n stages of D ₁ , D ₂ ... D _k , ... D _n . Note that K ₁ indicates the inside and K ₂ indicates the outside. The tips of the magnetic steel sheets are piled up so that the angle between the direction of stacking the iron core legs 2 and the width direction is 60 degrees.

FIG. 5 is a plan view (A) showing the shape of the 60-degree joint portion of the yoke portion of the embodiment of the triangular-arranged tripod core type three-phase transformer of the present invention, and a 90-degree view for comparison therewith. When the angle between the stacking direction and the width direction of the iron core leg in the plan view (B) of the joint is 90 degrees as in the conventional case, a void portion 6'is generated as shown in FIG. 5 (B). Therefore, as shown in FIG. 5 (A), the gap 6'can be made small by setting the angle between the stacking direction and the width direction of the iron core to be 60 degrees.

FIG. 6 is a sectional view of an iron core leg and a sectional view of a yoke of an embodiment of a triangularly arranged tripod core three-phase transformer of the present invention.
As shown in FIG. 6, the yoke 3 is gradually shifted in the longitudinal direction of the yoke in accordance with the joining with the core leg 2 at 60 degrees.

FIG. 7 is an explanatory view showing the outermost joint shape of the core block and the unit block of the D _k stage of the yoke in the embodiment of the triangularly arranged tripod core three-phase transformer of the present invention, and FIG. FIG. 3 is an explanatory view showing an innermost joint shape of the iron core leg and the yoke at the D _k stage of the embodiment of the triangular-arranged tripod core type three-phase transformer of the present invention, showing a case of the V-phase iron core leg. Here, 7 is a U-phase side yoke steel plate,
8 is a steel plate of a V-phase iron core leg on the U-phase side, 9 is a steel plate of a V-phase iron core leg on the W-phase side, and 10 is a steel plate of a W-phase side yoke. As shown in FIG. 7 and FIG. 8, the joint portion of the unit block of each stage of the iron core leg 2 and the yoke 3 is 30 with respect to the center line as shown in FIG.
The steel plates of the unit blocks of each stage of the iron core leg 2, that is, the steel plates 8 and W of the V-phase iron core leg on the U-phase side are arranged so as to be butt-joined to each other in a zigzag crossing direction at right and left angles.
The steel plate 9 of the V-phase iron core leg on the phase side is formed by abutting the long sides of the trapezoidal steel plates and opening the faces of these two trapezoidal steel plates by 60 degrees.
The hypotenuses of the trapezoidal steel plates 8 of the unit blocks of the respective steps of the iron core leg 2 are the hypotenuses of the tip ends of the trapezoidal steel plates 7 of the unit blocks of the respective steps of the yoke 3,
The hypotenuses of the upper and lower ends of the trapezoidal steel plate 9 of the unit block are formed by being joined to the hypotenuses of the tips of the trapezoidal steel plates 10 of the unit blocks of each step of the yoke 3. The case of the U-phase or W-phase iron core leg is the same as that of the V-phase iron core leg.

Here, the K ₂ side (outer side) in FIG. 3 is a joint having the shape shown in FIG. 7, and the K ₁ side (inner side) in FIG.
And the value of H ₁ / (H ₁ + H ₂ ) is 10 to 50%, the value increases as it approaches K _1, and the value decreases as it approaches K ₂ , At K ₂ , the joint shape becomes the shape shown in FIG.

FIG. 9 shows the connecting positions of the steel plates at the joints of the _Dk stages of the core legs and yokes of the embodiment of the triangularly arranged three-leg iron core type three-phase transformer of the present invention with a certain fixed interval for each steel plate. It is explanatory drawing which shows the shape of the junction part alternately moved and laminated | stacked, and the case of a V-phase iron core leg is shown like FIG. 7 and FIG. Here, 11 is a steel plate of a U-phase side yoke, 12 is a steel plate of a U-phase side V-phase core leg, 13 is a steel plate of a W-phase side V-phase core leg, and 14 is a steel plate of a W-phase side yoke. . As shown in FIG. 9, the steel plate 11 of the U-phase side yoke part, the steel plate 12 of the U-phase side V-phase core leg, the steel plate 13 of the W-phase side V-phase core leg and the steel plate 14 of the W-phase side yoke are The connection positions are alternately moved and connected with a required lap margin (required interval) α for each steel plate. The case of the U-phase or W-phase iron core leg is the same as that of the V-phase.

FIG. 10 is a development view showing the details of the joint portion of each unit block of the iron core leg and the yoke in the embodiment of the triangularly arranged three-leg iron core type three-phase transformer of the present invention. As shown in FIG. The steel plate 15 of the iron core leg 2 and the steel plate 16 of the yoke 3 are alternately joined on both sides of the diagonal line at a position where a required lapping margin α is provided. The protruding portion 17 outside the 45 ° portion of the tip is cut off.

FIG. 11 is a diagram showing an embodiment of the triangularly arranged tripod core type three-phase transformer according to the present invention, in which the core legs and the yokes are joined at the D _k step, the silicon steel sheets are sequentially moved with a required lap margin. It is explanatory drawing which shows the shape of the joining part laminated | stacked by step lap laminated | stacked in the said several joining position, and shows the case of a V-phase iron core leg like FIG. Here, 18 is a steel plate of the U-phase side yoke, 1
9 is a steel plate of the V-phase iron core leg on the U-phase side, 20 is a steel plate of the V-phase iron core leg on the W-phase side, and 21 is a steel plate of the W-phase side yoke. As shown in FIG. 11, the steel plate 18 of the U-phase side yoke is the V-phase iron core leg 19 on the U-phase side, the steel plate 20 of the V-phase side V-core core leg on the W-phase side, and the steel plate 21 of the W-phase side yoke are in the respective directions. The connection position is sequentially moved and the connection is performed with a required lapping margin α for each silicon steel sheet. In this case, the connection position is moved back to the original position at every several positions, moved at the same interval, and repeatedly circulated for stacking.
The case of the U-phase or W-phase iron core leg is the same as that of the U-phase iron core leg.

When a non-oriented silicon steel sheet is used as the magnetic steel sheet, the joining portion of each stage of the core leg and yoke is constructed by alternately stacking strip-shaped non-oriented silicon steel sheets in an L-shape. .

Incidentally, the left and right zigzag-shaped abutting around K ₁ and K ₂ shown in FIG.
Since one magnetic steel plate (oriented silicon steel plate, non-oriented silicon steel plate, etc.) is cut at a right angle, a void portion 6 as shown in FIG. 4 exists. Magnetic properties can be improved by injecting magnetic powder into the voids 6 and curing the powder to fill the voids.

[0028]

Since the iron core of the triangularly arranged tripod core type three-phase transformer of the present invention has a structure in which the iron core legs are arranged in a tripod and the iron core yokes that join the iron core yoke at 60 degrees are laminated, Has the effect described in.

(1) The geometrical magnetic paths are the same in all three phases, and three-phase nonuniformity does not occur.

(2) The triangular arrangement of the iron core legs makes it possible to reduce the installation area of the transformer.

(3) Theoretically, the magnetic flux of the yoke of the triangularly arranged tripod iron core is about 58% of the magnetic flux of the iron core leg, so the cross-sectional area of the upper and lower yokes is about 58% of the cross-sectional area of the iron core leg. It improves, and therefore the height of the iron core can be reduced.

(4) The reduction of the iron core height is advantageous in transportation.

(5) Noise is reduced because the magnetic circuit is three-phase balanced.

(6) When assembling iron cores in different directions, the joints are abutted in a zigzag pattern on the left and right instead of being straight, so that the mechanical strength is increased.

(7) Since the steel plates of the iron core legs or the joints of the ends of the steel plates of the yoke are aligned at an angle of 60 degrees, the voids are reduced, the magnetic characteristics are improved, and the core noise is reduced.

(8) Magnetic noise is reduced and magnetic characteristics are improved by injecting magnetic powder into the voids of the left and right zigzag-shaped iron core legs and yokes and hardening them to fill the voids. it can.

[Brief description of drawings]

FIG. 1 is a perspective view showing the shape of an iron core according to an embodiment of a triangular arrangement tripod core type three-phase transformer of the present invention.

FIG. 2 is a plan view showing the shape of an iron core according to an embodiment of a triangularly arranged tripod core three-phase transformer of the present invention.

FIG. 3 is a plan view showing the shape of the iron core of the embodiment of the triangularly arranged tripod core type three-phase transformer of the present invention.

FIG. 4 is an enlarged plan view showing the shape of the D _k step of the iron core of the embodiment of the triangularly arranged tripod core type three-phase transformer of the present invention.

FIG. 5 is a plan view (A) showing a shape of a joint portion in which yokes are joined at 60 degrees in the embodiment of the triangular arrangement tripod core type three-phase transformer of the present invention, and this plan view (A). The top view (B) of the joining part which joined the yoke part at 90 degrees for comparison.

6A and 6B are a cross-sectional view showing an iron core leg and a cross-sectional view showing a yoke portion of an embodiment of a triangular arrangement tripod core three-phase transformer of the present invention.

FIG. 7 is an explanatory view showing the outermost joint shape of the core leg and the yoke at the D _k stage of the embodiment of the triangularly arranged tripod core three-phase transformer of the present invention.

FIG. 8 is an explanatory view showing the innermost joint shape of the core leg and the yoke at the D _k stage in the embodiment of the triangularly arranged tripod core three-phase transformer of the present invention.

FIG. 9 is a diagram showing an embodiment of a triangular-arranged tripod core type three-phase transformer of the present invention, in which a D _k stage joint of an iron core leg and a yoke is moved alternately at a required constant interval for each steel plate. Explanatory drawing which shows the shape of the junction part made into the laminated | stacked alternating stack.

FIG. 10 is a development view showing details of a joint portion of each unit block of an iron core leg and a yoke of an embodiment of a triangularly arranged tripod core three-phase transformer of the present invention.

FIG. 11 is a view showing a plurality of _Dk- stage joints of an iron core leg and a yoke of the embodiment of the triangular-arranged tripod core type three-phase transformer of the present invention, which are sequentially moved at predetermined constant intervals for each steel plate. Explanatory drawing which shows the shape of the joining part which carried out the step lap stacking laminated | stacked at a joining position.

FIG. 12 is a plan view of a tripod core of a conventional three-phase transformer.

FIG. 13 is a plan view of a tripod core of a conventional three-phase transformer.

[Explanation of symbols]

1 ... Winding 2 ... Iron core leg 3 ... Yoke 4 ... Iron core 5 ... Insulation cylinder 6,6 '... Void 7, 11, 18 ... Steel plate of U-phase side yoke 8, 12, 19 ... U-phase side Steel plate after V phase iron core 9,13,20 ... Steel plate of V phase iron core leg on W phase side 10, 14, 21 ... Steel plate of yoke iron on W phase side 15 ... Steel plate of iron core leg 16 ... Steel plate of yoke iron 17 ... Projection D ₁ , D ₂ , D _k , D _n … Number of blocks H ₁ … Width of straight part of yoke tip H ₂ … Width of hypotenuse of yoke tip K ₁ −K ₂ … Center line α… Steel plate Lap fee

Claims (6)

[Claims] 1. Two sets of unit blocks are stacked by stacking magnetic steel sheets each having a required width into a parallelogram shape having a transverse cross-section with an acute angle of 60 degrees and an obtuse angle of 120 degrees. The blocks are butted and joined at an angle of 60 degrees, and the axes of the three iron core legs formed by stacking them so that their outer tangent lines are approximately circular are arranged at the vertices of an equilateral triangle and stand side by side. The magnetic steel plates having a required width are provided above and below each of the two legs of the three iron core legs. It is characterized in that the yokes formed by stacking unit blocks of multiple stages that are stacked at an angle of 60 degrees are arranged and joined at an angle of 60 degrees between each two core legs. Triangle iron core type three-phase transformer. 2. The magnetic steel sheet is a grain-oriented silicon steel sheet or a non-oriented silicon steel sheet, and the joint portion of the core leg and the core leg and the unit block of each step of the yoke and the yoke is 30 with respect to the center line.
It is arranged so as to be butt-joined to each other at a line intersecting in a zigzag manner at right and left angles, and the long sides of the trapezoids of the unit blocks at each stage of the iron core legs are butted, and the faces of these two trapezoidal unit blocks The hypotenuses of the upper and lower ends of the trapezoidal unit block of each stage of the iron core leg are arranged to be arranged in a V shape opened by 60 degrees, and are joined to the hypotenuse part of the tip of the unit block of each stage of the yoke. The tripod core type three-phase transformer having a triangular arrangement according to claim 1, wherein 3. The joining positions of the silicon steel plates of the unit blocks of the respective stages of the iron core leg and the yoke are alternated stacks in which the silicon steel plates are alternately moved and laminated at predetermined constant intervals for each silicon steel plate. The tripod core type three-phase transformer with triangular arrangement according to claim 2, wherein 4. A step lap stacking in which the joining positions of the silicon steel plates of the unit blocks of each stage of the iron core leg and the yoke are sequentially moved at a predetermined constant interval for each silicon steel plate at a plurality of joining positions. 3. The method according to claim 2, wherein
Triangle iron core type three-phase transformer as described in. 5. The magnetic steel sheet is a non-oriented silicon steel sheet, and the joining portions of each stage of the core leg and yoke are formed by alternately stacking strip-shaped non-oriented silicon steel sheets and joining them in an L-shape. The tripod iron core type three-phase transformer having a triangular arrangement according to claim 1. 6. The method according to claim 2, wherein the magnetic powder is injected into the gaps between the left and right zigzag-shaped iron core legs and the yokes, and the gaps are filled to fill the gaps. 5. A tripod iron core type three-phase transformer having a triangular arrangement according to any one of 5 above.