Active part of transformer and its assembly method

Abstract

FIELD: electrical engineering.SUBSTANCE: declared active part of the transformer comprises a magnetic circuit with insulating strips installed on it. The rails on the magnetic circuit are pulled together until they are immobile with bandage tapes, and the windings are installed on top of the bandage tapes. The method for assembling the active part of a transformer includes the following stages: installing insulating strips on a magnetic circuit, tightening the magnetic circuit with the strips installed on it with bandage tapes until the strips on it are immobile, and installing windings on the magnetic circuit over the bandage tapes.EFFECT: increase in the reliability of securing the rails on the core of the transformer magnetic circuit and, as a consequence, an increase in the reliability of the transformer during operation and transportation.8 cl, 2 dwg

Description

[0001] Technical field

[0002] The group of inventions relates to mechanical engineering, and more specifically to the production of transformers.

[0003] Technology Level

[0004] Electrodynamic stability is one of the key indicators in the operation of transformers and reflects the ability of a transformer to withstand, without damage, the mechanical forces that arise in its windings and current-carrying parts during the flow of short-circuit currents.

[0005] To achieve the required electrodynamic strength, transformers are equipped with rails made of durable dielectric material, securely fastened to the magnetic circuit in such a way that they form a rigid frame that prevents displacement, deformation or damage to the windings under the action of large electrodynamic forces that arise during a short circuit.

[0006] Great importance in the design is given to fixing the rails on the magnetic circuit, so as to prevent them from falling out during vibrations caused by transportation or operation of the transformer.

[0007] A transformer is known, described in document SU 1107182 (published 07.08.1984, applicant PRODUCTION ASSOCIATION "URALELEKTROTYAZHMASH" NAMED AFTER V.I. LENIN), [1], and containing a magnetic circuit, on the rods of which concentric windings are placed, and between the windings there are spacers made in the form of a rail with a longitudinal groove, in which a rod is placed, the thickness of which is greater than the depth of the groove, equipped with horizontal grooves and a protrusion in the lower part, and the bandages are placed in the horizontal grooves of the gaskets, and the rods rest against the protrusion.

[0008] The disadvantages of this solution include its complex design, the presence of additional rods and spacers making it heavier and more difficult to assemble, requiring a large amount of materials and time. The spacers are secured by the protrusions of the spacers and the edges of the grooves. However, this fixation is not rigid, and unwanted movement of the spacers is possible during transport or operation.

[0009] A coil is known, disclosed in the Russian Federation patent No. 80990 U1 for the utility model "Coil" (published on 27.02.2009, applicant Open Joint-Stock Company "Elektrovypryamitel"), [2], and containing a rectangular rod magnetic circuit, windings, an insulating element located between the rectangular rod magnetic circuit and the windings, characterized in that the rectangular rod magnetic circuit is made stepped, and insulating strips are installed in the grooves between the steps of the magnetic circuit for the length of the placement of the windings, wherein the outer edge of the insulating strips is rounded, and the insulating element located between the magnetic circuit and the windings is made flexible.

[0010] The disadvantages of solution [2] include a complex design containing a flexible insulating element located between the magnetic core and the windings, the installation of which requires the use of additional materials. Installing insulating strips in the slots between the magnetic core stages does not ensure the immobility of the strips during transportation and operation of the transformer, which may result in their loss.

[0011] The well-known solution [1] is adopted as a prototype.

[0012] Both known devices feature a complex design with additional insulation and fastening elements, which requires extensive assembly and does not ensure the rails are completely immobilized, causing them to fall out. Neither of the presented solutions mentions a method for preventing the rails from becoming clogged between the magnetic circuit and the windings.

[0013] Essence of the invention

[0014] The problem solved by the claimed group of inventions is the loss of insulating strips during transportation and operation of the transformer.

[0015] The technical result achieved by the claimed group of inventions is to increase the reliability of fixing the rails on the core of the magnetic circuit, and as a consequence, to increase the reliability of the transformer during operation and transportation, while simplifying the design of the active part of the transformer and the process of its assembly, eliminating damage to the winding and magnetic circuit at the stage of production and transportation, thereby contributing to an increase in the reliability of the entire transformer.

[0016] The claimed group of inventions includes an active part of a transformer and a method for assembling this active part, which are characterized by the following corresponding special technical features that distinguish each of the inventions of the group from its closest analogue.

[0017] The declared active part of the transformer contains:

[0018] - magnetic circuit with insulating strips installed on it;

[0019] - the rails on the magnetic circuit are pulled together until they are immobile with bandage tapes, which ensures their reliable fixation during transportation and operation of the transformer, preventing them from falling out;

[0020] - windings installed on top of bandage tapes, which eliminates the need to drive the rails into the active part of the transformer and thus the windings and magnetic circuit are not subject to deformation.

[0021] For maximum effect on the rails, an adhesive bond can be applied between the insulating rails and the magnetic core rod, which eliminates the displacement of the rails when they are tightened with bandage tapes on the magnetic core rod, reducing the likelihood of the rails shifting along the magnetic core rod.

[0022] Preferably, the insulating slats are made with grooves where the bandage tapes are placed, due to which the bandage tapes do not move along the slats when tightened.

[0023] Additionally, the insulating slats can be made with rounded edges so that they are not damaged by sharp edges when tightened with bandaging tapes.

[0024] The declared active part ensures a simple design, reduced material consumption during production, reliable fixation of the rails, due to which the likelihood of damage to the winding and magnetic circuit, and as a result the transformer, is significantly reduced.

[0025] The claimed method for assembling the active part contains the following stages:

[0026] - install insulating strips on the magnetic circuit to prevent contact between the magnetic circuit and the winding;

[0027] - tighten the magnetic circuit with the rails installed on it with bandage tapes until the rails on it become motionless, which ensures a strong fixation of the rails, preventing them from falling out, and also speeds up the assembly process;

[0028] - windings are installed on the magnetic circuit over the bandage tapes, which eliminates the need to hammer in the rails after installing the windings, thereby preserving the windings and magnetic circuit without mechanical damage.

[0029] Additionally, the method includes a step in which bandage tapes are placed in the grooves of the insulating slats, which speeds up the assembly process and ensures a constant location of the bandage tapes during the assembly of the active part by eliminating the need to hammer in the insulating slats.

[0030] It is preferable to apply adhesive to the slats before installing them, providing additional fixation of the slats during the assembly process.

[0031] The claimed method ensures the quick assembly of a reliable and simple active part, which eliminates damage to the magnetic circuit and windings both during the assembly process by eliminating clogging of the rails when the windings are installed, and during transportation and operation during vibrations due to reliable fixation of the rails, and also eliminates unwanted contact between the winding and the magnetic circuit.

[0032] Brief description of drawings

[0033] The essence of the stated solution is explained by figures depicting:

[0034] Fig. 1 - longitudinal sectional view of the magnetic core of the active part of the transformer, where (1) is the magnetic core, (2) is the magnetic core, (3) are the rails, (4) is the winding.

[0035] Fig. 2 - the core of the magnetic circuit of the active part of the transformer, cross-sectional view, where in addition (5) there is a bandage tape.

[0036] Detailed Description

[0037] The active part of the transformer according to the claimed invention comprises a magnetic circuit (1) with at least two insulating strips (3) secured to its rod (2), fastening elements (not shown), and winding taps (not shown) (4).

[0038] The insulating strips (3) are installed on the magnetic circuit by means of a fixed connection, provided with their rigid fixation by bandage tapes (5), by tightening the strips (3) around the rod (2) (see Fig. 2).

[0039] As an additional layer of the active part between the insulating strips (3) and the magnetic circuit, there can be an adhesive joint applied to the side of the strip (3) facing the rod (2) of the magnetic circuit (1), which eliminates the displacement of the strips (3) during further assembly of the transformer and helps maintain the established position in the finished transformer.

[0040] Adhesive bonding refers to any suitable adhesive bond, applied as a continuous layer or in spots, or by any other method that ensures the adhesion of the rails (3) to the magnetic core (1). Adhesive bonding of the rails to the core provides additional fixation and prevents free movement, which greatly simplifies assembly and the design of the active part itself.

[0041] Fixing the insulating strips (3) in two places—at the top and bottom—ensures optimal pressure along the entire length of the strips (3), which facilitates a secure, immovable installation of the strips (3) on the core (2) of the magnetic circuit (1). Three or more bandage straps (5) can be additionally installed to apply even greater pressure to the strips (3) to ensure their immobility.

[0042] The length of the rails (3) can be equal to the height of the magnetic core window (1) or 2-10 mm shorter than the height of the magnetic core window (1). This is determined by the dimensions of the finished transformer in which the active part is installed, providing additional vibration reduction for the rails (3) themselves during transportation.

[0043] The rail (3) can be made as a single piece or as a composite piece, which does not affect the function it performs.

[0044] Additionally, the slats (3) may contain grooves for placing the bandage tapes (5), thereby preventing the bandage tapes (5) from moving along the slats (3), which in some cases may lead to a decrease in the pressure exerted by the bandage tapes (5) on the slats (3).

[0045] Preferably, the rails (3) can be made with rounded edges, which helps to avoid possible damage to the bandage tapes (5) when tightening, thus contributing to the additional reliability of the structure and fixation of the rails (3), eliminating their falling out, and as a consequence, contact of the winding (4) and the magnetic circuit (1), leading to damage to the device.

[0046] The slats (3) are made of dielectric material, such as, but not limited to, fiberglass, fiberglass and other suitable materials.

[0047] In this design, the inner and outer windings (4) are installed over the rod (2) with the slats (3) and banding straps (5) already attached to it. This is in comparison to prior art solutions, where the installation of the slats by hammering occurs after the installation of the windings.

[0048] The claimed design of the active part of the transformer ensures reliable fixation of the rails (3) on the magnetic circuit (1), ease of assembly, eliminates the need to fix the rails (3) by hammering after installing the windings (4), reduces the likelihood of their damage and the labor intensity of production.

[0049] The design options of the device are explained by examples of the implementation of the active part with two and four insulating strips.

[0050] In one embodiment, two insulating strips, located diametrically opposite each other, are installed on each leg of the transformer's active magnetic circuit. The two strips create two main vertical cooling channels between the winding and the magnetic circuit. This design has sufficient mechanical strength to withstand pressing forces, electrodynamic loads, and vibration during transportation and operation. When the transformer experiences vibration during transportation or operation, the two strips, secured with banding straps, are firmly pressed against the magnetic circuit on two opposite sides of the core. In addition to the cooling channel, they form a spacer layer, preventing the windings from contacting the magnetic circuit and causing damage. The pressure of the banding straps on the strips and their compression against the magnetic circuit core ensures their secure attachment, preventing their loss.

[0051] The four-insulation-bar design ensures equidistant placement of four insulating bars on each magnetic core leg, creating four cooling channels and tight and uniform contact between the winding and the fixed insulating bars. The bars are secured with bandages placed above and below the bars, preventing them from falling out. When the transformer vibrates, the winding rests against the insulating bars without touching the magnetic core, thus eliminating the possibility of damage to the active components of the transformer.

[0052] Using a single insulating strip in the active section of a transformer is not recommended, as it will not securely hold the heavy winding. Also, tightening the banding straps on a single strip and the magnetic core will not securely hold the strip. This misalignment may cause the strip to fall out, causing the winding to become displaced, resulting in damage.

[0053] The method of assembling the active part of the transformer is as follows.

[0054] First, rails (3) are installed on the rod (2) of the magnetic circuit (1), providing an insulating layer.

[0055] Next, the core (2) of the magnetic circuit (1) with the rails (3) is wrapped with banding straps (5), at least at the top and bottom. Preferably, the banding straps (5) are positioned in the grooves of the rails (3), which reduces the possibility of the straps moving along them, thereby providing additional immobility of the fastening.

[0056] After this, the core (2) of the magnetic circuit (1) and the strips (3) placed on it are tightened with bandage tapes (5) until each insulating strip (3) becomes motionless along its entire length, thereby achieving reliable, rigid fixation of the strips (3) on the core (2) of the magnetic circuit (1). The insulating strips (3) fixed in this way in the active part of the transformer do not fall out during its transportation and operation, maintaining the high electrodynamic stability of the transformer.

[0057] After the bandage tapes (5) are tightened on the magnetic circuit (1), the inner and outer windings (4) and taps (not shown) are installed.

[0058] Additionally, for the fastest possible assembly, before installing the insulating strips (3) on the rod (2) of the magnetic circuit (1), an adhesive joint can be applied, ensuring an unchanged position of the strips during further assembly of the active part.

[0059] Installing the windings (4) after fixing the rails on the rod (2) of the magnetic circuit (1) prevents the rails (3) from becoming clogged when the windings (4) are already installed, thereby preventing damage to the windings (4) and the rod (2) of the magnetic circuit (1), ensuring the reliability and integrity of the structure, and also facilitating the process of assembling the active part of the transformer.

[0060] The active part of the transformer, as well as its assembly method, with its simplicity, ensures reliable fastening of the insulating strips on the core of the magnetic circuit, which eliminates their loss during transportation and operation of the transformer, and as a result reduces the likelihood of transformer failure, increasing its reliability.

Claims

1. The active part of the transformer, containing - a magnetic circuit with at least two insulating strips installed on it, and windings, characterized in that - the insulating strips on the magnetic circuit are pulled together with bandage tapes until they are immobile, - windings are installed over the bandage tapes.

2. The active part of the transformer according to paragraph 1, characterized in that an adhesive connection is made between the insulating strips and the core of the magnetic circuit.

3. The active part of the transformer according to paragraph 1, characterized in that the insulating strips are made with grooves where the bandage tapes are placed.

4. The active part of the transformer according to paragraph 1, characterized in that the insulating strips are made with rounded edges.

5. The active part of the transformer according to paragraph 1, characterized in that the active part contains at least two bandage tapes.

6. A method for assembling the active part of a transformer, comprising the steps of: - install insulating strips on the magnetic circuit, characterized in that, - the insulating strips on the magnetic circuit are tightened with bandage tapes until they become motionless; - windings are installed on the magnetic circuit over the bandage tapes.

7. The method for assembling the active part according to paragraph 6, characterized in that it additionally comprises a step in which an adhesive connection is made between the insulating strips and the core of the magnetic circuit.

8. The method for assembling the active part according to paragraph 6, characterized in that it additionally contains a step in which bandage tapes are placed in the grooves of the insulating slats.

Images