A 220kV transformer lead clamping structure for middle outlet

Abstract

The present invention relates to a 220 kV transformer lead clamping structure for a middle outlet, belonging to the technical field of transformers. The technical scheme is as follows: a top-connected trapezoidal paperboard (1) is a double trapezoidal shape with two upper bottom edges connected together by a rectangular plate (10), the two trapezoids are bent toward the same side of the rectangular plate (10), the two lower bottom edges of the top-connected trapezoidal paperboard (1) are tied to a bottom paperboard (2) by a shrink band (8), the bottom paperboard (2) is tied to a transformer body (9) by multiple polyester binding bands (7), the high-voltage lead (4) is fixed to a rectangular plate between the two upper bottom edges of the top-connected trapezoidal paperboard (1) by a winged U-shaped fixing plate (5) and an insulating screw (6), and a flat paperboard (3) is provided between the winged U-shaped fixing plate (5) and the rectangular plate between the two upper bottom edges of the top-connected trapezoidal paperboard. The beneficial effects of the present invention are: the structure is simple and can meet the requirements of mechanical properties and electrical strength.

Description

Technical Field

[0001] The invention relates to a 220kV grade transformer lead clamping structure for middle outlet, belonging to the technical field of transformers. Background Art

[0002] In the power transformer or traction transformer industry, the capacity and current of the 220kV level are relatively small. When the high-voltage lead is connected in the middle of the transformer body, it is necessary to increase the clamping of the lead to improve the reliability of the product. An economical, simple and reliable clamping method is very important. It should not be too complicated to increase the product cost, but should meet the product's requirements for mechanical properties and electrical strength.

[0003] At present, the commonly used clamping method is to remove the spacers between coil segments at four suitable positions corresponding to the high-voltage lead wires in the outermost coil of the device body, and replace them with four longer wire clamps so that the other end of the wire clamp passes through the device body screen and extends to the outside, and then a wire clamp with a circular arc notch is placed horizontally and fixed to the ends of the four long wire clamps extending out of the screen with an insulating screw. Finally, two U-shaped wire clamps are used to fix the high-voltage lead wire to the horizontally placed wire clamp. Although this clamping method has a simple structure, it requires increasing the size of the local horizontal oil channel of the coil to place the wire clamp. In addition, holes need to be opened at the corresponding positions of the device body screen so that the four long horizontal and longitudinal wire clamps can pass through and extend, which will cause local weakening of the insulation strength of the screen and leave hidden dangers. In addition, this support method has low mechanical strength and poor short-circuit resistance, and can only be used for small-capacity products. Summary of the invention

[0004] The purpose of the present invention is to provide a 220kV transformer lead clamping structure for middle outlet, which has a simple structure, can meet the requirements of mechanical performance and electrical strength, and solve the problems existing in the background technology.

[0005] The technical solution of the present invention is:

[0006] A 220kV transformer lead clamping structure for a middle outlet comprises a top-connected trapezoidal paperboard, a bottom paperboard, a flat paperboard, a high-voltage lead, a U-shaped fixing plate with wings, an insulating screw, a polyester binding tape, a shrink tape and a transformer body. The top-connected trapezoidal paperboard is a double trapezoid with two upper bottom edges connected together by a rectangular plate, the two trapezoids are bent toward the same side of the rectangular plate, the two lower bottom edges of the top-connected trapezoidal paperboard are bound to the bottom paperboard by a shrink tape, the bottom paperboard is bound to the transformer body by multiple polyester binding tapes, the high-voltage lead is fixed to the rectangular plate between the two upper bottom edges of the top-connected trapezoidal paperboard by a U-shaped fixing plate with wings and an insulating screw, and a flat paperboard is provided between the U-shaped fixing plate with wings and the rectangular plate between the two upper bottom edges of the top-connected trapezoidal paperboard.

[0007] The bottom paperboard is rectangular.

[0008] The bottom paper board is fixed at a position of the transformer body close to the middle outlet line.

[0009] The flat paperboard is arranged on a rectangular plate between two upper bottom edges of the top trapezoidal paperboard, and the rectangular plate between two upper bottom edges of the top trapezoidal paperboard, the flat paperboard and the U-shaped fixing plate with wings are connected together through four insulating screws.

[0010] The winged U-shaped fixing plate is composed of two integrally formed rectangular plates and a U-shaped plate connected in sequence, and the two rectangular plates are symmetrically arranged at both ends of the U-shaped plate, and the whole is similar to an Ω shape.

[0011] The beneficial effect of the present invention is that since the current in the high-voltage lead wire of the 220kV grade product is relatively small, the electromotive force caused by the leakage magnetic field during a short circuit fault is also relatively small, therefore, as long as the insulating paperboards of the top trapezoidal paperboard, the bottom paperboard and the flat paperboard are selected with appropriate thickness, the requirements for mechanical strength can be met, and the requirements for insulation strength of the part can be met. The clamping method has a simple structure, is firm and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the present invention;

[0013] Figure 2 is a cross-sectional view of the present invention;

[0014] Figure 3 It is a structural schematic diagram of a top-connected trapezoidal paperboard;

[0015] In the figure: 1. Trapezoidal cardboard with top; 2. Bottom cardboard; 3. Flat cardboard; 4. High-voltage lead; 5. U-shaped fixing plate with wings; 6. Insulating screw; 7. Polyester binding tape; 8. Shrink tape; 9. Transformer body; 10. Rectangular plate. DETAILED DESCRIPTION

[0016] The present invention will be further described below by way of examples with reference to the accompanying drawings.

[0017] Refer to the attached Figures 1 to 3A 220kV grade transformer lead clamping structure for middle outlet includes a top trapezoidal paperboard 1, a bottom paperboard 2, a flat paperboard 3, a high-voltage lead 4, a winged U-shaped fixing plate 5, an insulating screw 6, a polyester binding tape 7, a shrinking tape 8 and a transformer body 9. The top trapezoidal paperboard 1 is a double trapezoid with two upper bottom edges connected together by a rectangular plate 10, and the two trapezoids are bent to a certain angle on the same side of the rectangular plate 10. The two lower bottom edges of the top trapezoidal paperboard 1 are tied to the bottom paperboard 2 by the shrinking tape 8, and the bottom paperboard 2 is tied to the transformer body 9 by multiple polyester binding tapes 7. The high-voltage lead 4 is fixed to the rectangular plate 10 between the two upper bottom edges of the top trapezoidal paperboard 1 by the winged U-shaped fixing plate 5 and the insulating screw 6. A flat paperboard 3 is provided between the winged U-shaped fixing plate 5 and the rectangular plate 10 between the two upper bottom edges of the top trapezoidal paperboard 1.

[0018] In this embodiment, as shown in the attached Figure 3 As shown, the top-connected trapezoidal paperboard 1 is made of a 3-5mm thick insulating paperboard, which is first cut into a double trapezoidal shape connected together by a rectangular plate 10, then bent along the dotted line and tied to a rectangular insulating bottom paperboard 2 of the same thickness with a shrink band 8 to make the structure stable and secure. Figure 1 , 2 , as shown. The rectangular insulating bottom paperboard 2 is fixed on the transformer body 9 with four polyester binding tapes 7, and then the 10mm thick insulating paperboard is placed as a flat paperboard 3 on the rectangular plate 10, and finally the high-voltage lead 4 is fixed on the rectangular plate 10 between the double trapezoids with four insulating screws 6 through the winged U-shaped fixing plate 5 formed by bending the 10mm thick insulating paperboard.

Claims

1. A 220kV transformer lead clamping structure for middle outlet, characterized in that: The invention comprises a top-connected trapezoidal paperboard (1), a bottom paperboard (2), a flat paperboard (3), a high-voltage lead (4), a winged U-shaped fixing plate (5), an insulating screw (6), a polyester binding belt (7), a shrinking belt (8) and a transformer body (9). The top-connected trapezoidal paperboard (1) is a double trapezoidal shape with two upper bottom edges connected together by a rectangular plate (10), the two trapezoids are bent toward the same side of the rectangular plate (10), the two lower bottom edges of the top-connected trapezoidal paperboard (1) are bound to the bottom paperboard (2) by a shrinking belt (8), the bottom paperboard (2) is bound to the transformer body (9) by a plurality of polyester binding belts (7), the high-voltage lead (4) is fixed to the rectangular plate (10) between the two upper bottom edges of the top-connected trapezoidal paperboard (1) by the winged U-shaped fixing plate (5) and the insulating screw (6), and a flat paperboard (3) is provided between the winged U-shaped fixing plate (5) and the rectangular plate (10) between the two upper bottom edges of the top-connected trapezoidal paperboard (1).

2. A 220kV transformer lead clamping structure for middle outlet according to claim 1, characterized in that: The bottom paperboard (2) is rectangular.

3. A 220kV transformer lead clamping structure for middle outlet according to claim 1 or 2, characterized in that: The bottom paper board (2) is fixed at a position of the transformer body (9) close to the middle outlet line.

4. A 220kV transformer lead clamping structure for middle outlet according to claim 1 or 2, characterized in that: The flat paperboard (3) is arranged on a rectangular plate (10) between two upper bottom edges of the top trapezoidal paperboard (1); the rectangular plate (10) between two upper bottom edges of the top trapezoidal paperboard (1), the flat paperboard (3) and the winged U-shaped fixing plate (5) are connected together via four insulating screws (6).

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