JPH0739211Y2 - Foil winding transformer - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to a foil winding transformer having a tap coil.

B. Outline of the Invention This device aims at downsizing of a foil wound transformer by stacking the output conductors in the reverse order of the tap drawing order and fixing them along the axial direction of the outer circumference of the tap coil. It is a thing.

C. Prior art Fig. 2 shows a conventional foil wound transformer with a tap coil.
Is a transformer core, 2 is an iron core clamp, 3 is an insulating cylinder, 4 is a low-voltage winding wound around the outer circumference of the insulating cylinder 3, and 5 is an insulating gap (or insulator) around the outer circumference of the low-voltage winding 4. The low-voltage winding 4 and the tap coil 5 are formed by winding a thin foil-shaped metal sheet 6 which is a coil and is insulated by an insulating sheet 7. Reference numeral 8 denotes a strip-shaped lead conductor provided in the tap lead-out portion of the tap coil 5. The lead-out conductor 8 is displaced in the circumferential direction to maintain the insulation distance between the lead conductors, for example, the tip portion is formed into a cylindrical shape. Then, the connection conductor 9 is connected. Reference numeral 10 is a support insulator of the connection conductor 9, and 11 and 12 are connection conductors of other tap coils. These connection conductors are connected to terminals of a tap changer (not shown).
Reference numeral 13 shows the tank wall of this foil wound transformer.

D. Problem to be solved by the invention A foil wound transformer can be made smaller than a conventional transformer if the space factor of the winding is good and the ratings are the same, and the winding work is easy to automate. It has been widely adopted because it can improve productivity.

However, in a foil wound transformer equipped with a tap coil, the lead-out portion and the connecting conductor of the tap have to be pulled out or arranged with a predetermined insulation distance maintained, and the lead-out portion is weakened. Often, the connecting conductor travels outside the outer diameter of the tap coil or travels above the tap coil.

If the distance from the outermost conductor on the business trip to the inner wall surface of the tank is made equal to the predetermined insulation distance, the outer diameter of the transformer tank will be large even though the outer diameter of the winding portion will be small, and The intended purpose of miniaturization cannot be achieved.

Therefore, an object of the present invention is to reduce the size of a foil winding transformer provided with a tap coil.

E. Means for Solving the Problem The means for solving the above problem in the present invention is to install a thin strip-shaped lead conductor for pulling out a tap from a tap coil in an insulating sheet in the reverse order of the tap pulling order. The lead conductors are overlapped with each other and are aligned along the axial direction of the outer circumference of the tap coil and fixed.

F. Action The connection conductors concentrated on the upper part of the tap coil are also distributed on the outer periphery of the tap coil. The outermost tap and the tap coil side of the lead conductor are set to the same potential, and the insulation dimension therebetween is set to almost zero.

G. Embodiment FIG. 1 shows an embodiment of the present invention. In the figure (A)
The figure is a longitudinal cross-sectional view of an essential part, (B) is an explanatory view of part A in (A), (C) is a cross-sectional view taken along the line I-A in (B),
FIG. 3D is a plan view of a main portion of the tap coil portion showing the relationship between the output conductor and the connection conductor of another tap coil. The same parts as those in FIG. 2 are designated by the same reference numerals and the description thereof will be omitted.

In the figure (A), 14 is an inner terminal of the tap coil 5,
Similar to the lead conductor provided in the tap lead-out portion of the tap coil 5, the tap coil 5 is made of a thin strip plate or foil-like conductor, and the tip end portion is formed, for example, in a cylindrical shape and connected to the terminal conductor. 15, 16 are terminal conductors of other tap coils, 17 is a support insulator of the terminal conductors, which are attached to the iron core clamp 2,
The tip does not travel beyond the outer circumference of the tap coil 5. Reference numeral 18 is a lead conductor which is laminated in the reverse order of the tapping order through an insulating sheet, and is aligned along the axial direction of the outer periphery of the tap coil 5 and the binding tape is appropriately placed.
Fix it to the outer circumference of the tap coil 5 and connect the connecting conductors in order from the outer conductor.
2. Line up in the tap pull-out order like T5. FIG. 5B is an enlarged view of the part A in FIG.
It is a tap, but in this explanatory view, it is 3 taps for simplicity. (B) As is apparent from the figure, the tap conductors 61, 62, 63 are aligned with the tap conductors 61, 62, 63 from the bottom, and the output conductors of the horizontal conductors are overlapped as shown in FIG. In the vertically drawn out portions aligned in the direction, the insulating sheets 73 are stacked from the inner side toward the outer side in the order of 63, 62, 61, which is the reverse of the tapping order. 71 is a foil metal sheet 6
It is a tape-shaped insulating sheet having the same thickness as the above, and is arranged on both edges of the foil-shaped metal sheet 6 so as to have the same width as the insulating sheet 7. 72 is the outer circumference insulation of the tap coil 5. As is clear from the figure (B), since the outermost peripheral foil-shaped metal sheet of the tap coil 5 and the lead conductor 63 have the same potential, the insulating strength between them is not particularly required, and the mouths of 61, 62, 63, etc. are not required. Since the taps have the same potential difference between the output conductors, the insulating layer 73 may have any insulation strength according to the potential difference. Therefore, the lead conductors 18 superposed like 61, 62, and 63 have a small thickness.
Further, the output conductor 18 is firmly fixed to the outer periphery of the tap coil 5 with a bind tape or the like as shown in FIG. In the figure (D), for example, when there are two sets of windings in a three-legged iron core, the connecting conductors of those other tap coils do not overlap the output conductor 18, and the number of taps is If there is a large number, the output conductors 18 that are overlapped may be drawn out from two or more places.

In the example described above, the inner terminal of the tap coil is described separately from the tap lead-out conductor, but the inner terminal of the tap coil is connected to the tap lead conductor via an insulator. The lead conductors and the connecting conductors, which are drawn out by overlapping, may not be connected only at the outer circumference of the tap coil, and the space above or below the tap coil may be used as appropriate. Good, in short, it should be done in a space formed by the outer diameter of the tap coil and the height of the iron core.

H. Effect of the Invention In the foil winding transformer provided with the tap coil according to the present invention, the output conductor for tapping is used as a strip-shaped output conductor with a thin thickness, and the tapping order is reversed. Since they are superposed through an insulating sheet, the insulation distance between the output conductors is extremely small, and the superposed output conductors are connected to the outer circumference of the tap coil along the axial direction of the tap changer terminal, etc. The connection conductors can be easily connected, and all connection conductors including terminal conductors can be stored in the space defined by the outer diameter of the tap coil and the height of the iron core. There is no such thing. In the embodiment, the connecting conductor travels to the outer circumference of the tap coil, but the protrusion thereof is extremely small. Therefore, the outer shape of the transformer tank becomes smaller as the outer diameter of the winding portion becomes smaller, and the intended purpose of downsizing the transformer can be achieved by adopting the foil winding.

Further, the superposed output conductors are firmly fixed to the outer circumference of the tap coil by a bind tape or the like, so that the strength at the time of a short circuit is improved and the reliability is enhanced, which is a practical effect.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, in which FIG. 1A is a longitudinal sectional view of a main part, FIG. 1B is an explanatory view of part A in FIG. 1A, and FIG. FIG. 6B is a cross-sectional view taken along the line I-A in FIG. 7B, and FIG. 6D is a plan view of a main portion of the tap coil showing the relationship between the output conductor and the connection conductor of another tap coil.
FIG. 2 is a longitudinal sectional view of a main part showing a conventional example. 5 ... Tap coil, 14,61,62,63 ... Band-shaped output conductor, 18 ... Overlaid output conductor, 19 ... Bind tape, etc., 73 ... Insulating sheet.

Claims (1)

[Scope of utility model registration request] 1. A foil winding transformer provided with a tap coil for drawing out a tap by means of a strip-shaped lead conductor having a thin thickness, wherein said lead conductor is provided with an insulating sheet in the reverse order of the tap drawing order. A foil winding transformer, characterized in that the lead conductors are overlapped with each other, and the combined lead conductors are fixed along the axial direction of the outer circumference of the tap coil.