Tap leading-out method and structure of transformer coil wound by multiple strands of flat copper wires

Abstract

The invention relates to a tap leading-out method and structure for a transformer wound by multiple strands of flat copper wires, and the method comprises the steps: combining the taps of the multiple strands of flat copper wires, and connecting a strand of leading-out wire with the combined tap, the leading-out wire being an enameled flat copper wire; welding the joint of the outgoing line and the combined tap by adopting argon arc welding, and quickly immersing the welded part in the cooling liquid after welding; and winding H-grade glass fiber adhesive tape on the cooled welding part, covering a NOMEX insulating paper board, and fixing the NOMEX insulating paper board by adopting the NOMEX adhesive tape. The taps of the multiple strands of flat copper wires are combined and then led out through argon arc welding, a single leading-out wire is welded through argon arc welding, a standard terminal hole can be well adapted, compared with tin soldering, argon arc welding has the advantages that the rigidity of the welding position is large, pseudo soldering is not prone to being generated, large impact current can be borne, heat conduction of argon arc welding to a welded object is slow, and the welding quality is improved. And cooling liquid is adopted to cool the welded part in time, so that the enameling damage caused by higher temperature rise of the taps can be effectively avoided, and the enameling damage area is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of winding transformer coils, and in particular to a tapping lead-out method and structure for winding transformer coils with multiple flat copper wires. Background Art

[0002] When the transformer coil is wound with multi-strand enameled flat copper wire, there is a problem: how to lead out the wire. Leading out multiple strands together makes subsequent bending difficult and the wire is thick and difficult to assemble. For example: it is difficult to roll the terminal of multi-strand enameled flat copper wire. Especially when connected with fully enclosed plastic terminals, since the standard terminal hole is designed according to the current carrying capacity of the wire, it can generally accommodate one strand of enameled flat copper wire. If it is a multi-strand enameled flat copper wire, the terminal size needs to be enlarged by 2 to 3 times to meet the insertion of the multi-strand enameled flat copper wire into the terminal hole. This is unreasonable both electrically and mechanically. Some manufacturers use soldering methods, that is, soldering the cable wire with the main wire to lead out, but the disadvantage is that it is easy to have a cold solder joint or it is difficult to withstand a large current shock. Some manufacturers have also tried to use high-frequency induction methods to weld the taps of multi-strand enameled flat copper wires, but the high temperature generated will cause large-scale damage to the paint skin of the enameled flat copper wire. Summary of the invention

[0003] Based on this, it is necessary to provide a tap lead method and structure for the transformer coil wound with flat copper wire that can adapt the lead wire of the transformer line to the standard terminal hole and withstand large current impact in order to solve the above technical problems.

[0004] The present invention provides a method for extracting taps from a transformer wound with multiple flat copper wires, comprising:

[0005] Merging the taps of multiple strands of flat copper wires, and connecting a lead wire to the merged tap, wherein the lead wire is an enameled flat copper wire;

[0006] Use argon arc welding to weld the lead wire and the combined tap connection, and quickly immerse the weld in coolant after welding;

[0007] After the weld is cooled, H-grade glass fiber tape is wrapped around it, and after covering it with the NOMEX insulating paperboard, the NOMEX insulating paperboard is fixed with the NOMEX tape.

[0008] In one embodiment, the step of merging the taps of multiple strands of flat copper wires and connecting a lead wire to the merged taps includes:

[0009] When winding multiple strands of enameled flat copper wire, arrange the multiple strands of flat copper wire in parallel and keep the end faces flush;

[0010] The end of the lead wire is superimposed on the tap of the multi-strand flat copper wire, and the axial direction of the lead wire is perpendicular to the axial direction of the tap.

[0011] In one embodiment, the tap superimposed on the multi-strand flat copper wire includes:

[0012] Overlay the flat side of the lead wire end onto the flat side of the multi-strand flat copper wire tap;

[0013] The end face of the lead wire is flush with the non-flat side of the flat copper wire lead arranged at the edge, and the non-flat side of the lead wire is flush with the end face of the multi-strand flat copper wire lead.

[0014] In one embodiment, the step of merging the taps of the plurality of flat copper wires and connecting the lead wires to the merged taps comprises:

[0015] When the enameled flat copper wires are wound in multiple strands, the tap of one of the flat copper wires is used as a lead wire, the taps of the remaining flat copper wires are stacked one by one, and the ends of the taps are exposed one by one, and the remaining flat copper wires are stacked on the one of the flat copper wires;

[0016] Adjust the length of the exposed ends of the remaining flat copper wires to be equivalent.

[0017] In one embodiment, the method of welding the lead-out wire and the combined tap connection by argon arc welding includes:

[0018] Select the current and argon gas flow rate of argon arc welding according to the specifications of the flat copper wire;

[0019] Controlled argon arc welding is used to quickly weld the connection between the lead-out wire and the combined tap.

[0020] In one embodiment, the step of rapidly immersing the welded portion in a coolant after welding comprises:

[0021] Immerse the weld in the coolant for 5-10 minutes, then take it out and observe the welding effect and temperature of the weld;

[0022] When the temperature is higher than the preset temperature, immerse the welded joint in the coolant repeatedly for 5-10 minutes, and observe the welding effect of the welded joint when the temperature is lower than the preset temperature;

[0023] When the welding effect reaches the standard, immerse the welded part in the coolant again until it reaches room temperature.

[0024] In one embodiment, after covering the NOMEX insulation paperboard, fixing the NOMEX insulation paperboard with a NOMEX tape comprises:

[0025] Two pieces of NOMEX insulating paperboard are clamped on both sides of the weld and fixed with NOMEX tape.

[0026] In one embodiment, the step of wrapping the cooled welded joint with an H-grade glass tape further comprises:

[0027] After the weld has cooled and dried, it is ground with a file to remove burrs.

[0028] In one embodiment, the method of fixing the NOMEX insulating paperboard with the NOMEX tape comprises:

[0029] Measure the DC copper resistance to determine whether it meets the welding standards.

[0030] The present invention also provides a tap lead-out structure for a transformer wound with multiple flat copper wires, which is manufactured by the tap lead-out method for a transformer wound with multiple flat copper wires as described above. The structure includes lead-out wires, welding portions and taps of multiple flat copper wires. The taps of multiple flat copper wires are stacked in sequence or arranged in parallel. The welding portions connect the stacked taps of multiple flat copper wires, and connect the lead-out wires and the taps of multiple flat copper wires. The welding portions are formed by argon arc welding.

[0031] The tap lead-out method and structure of the above-mentioned multi-strand flat copper wire wound transformer, after merging the taps of the multi-strand flat copper wires, is led out by argon arc welding into a single lead-out wire, which can better adapt to the standard terminal hole. In addition, compared with tin welding, argon arc welding has greater rigidity at the welding point, is less likely to produce cold welds and can withstand larger impact currents. Argon arc welding has a slow heat conduction to the welded object, and timely use of coolant to cool the weld can effectively avoid damage to the enamel package caused by high temperature rise of the tap, thereby reducing the area of ​​enamel package damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 A flowchart of a method for tapping a transformer wound with multiple flat copper wires according to an embodiment;

[0034] Figure 2 A schematic diagram of welding a lead-out wire and a multi-strand flat copper wire tap according to an embodiment;

[0035] Figure 3 A schematic diagram of welding the lead wires and the multi-strand flat copper wire taps according to another embodiment;

[0036] Figure 4 for Figure 2 A state diagram of the welded joint of the embodiment immersed in a coolant;

[0037] Figure 5 for Figure 3A state diagram of the welded joint of the embodiment immersed in a coolant;

[0038] Figure 6 for Figure 2 Schematic diagram of wrapping glass tape around the welding joint of the embodiment;

[0039] Figure 7 for Figure 2 Schematic diagram of fixing NOMEX insulation paperboard at the welding point of the embodiment;

[0040] Figure 8 The figure is a schematic diagram of the tap lead structure of a transformer wound with multiple flat copper wires according to an embodiment.

[0041] Reference numerals:

[0042] 310. Lead wire; 320. Welding part (welding point); 330. Multi-strand flat copper wire tap; 410. Container; 610. Glass fiber tape; 710. NOMEX insulating paperboard. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may be a central component at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in the specification of the present invention are for illustrative purposes only and do not represent the only implementation method.

[0045] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0046] In the present invention, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first feature is directly in contact with the second feature, or the first feature and the second feature are indirectly in contact through an intermediate medium. Moreover, a first feature being “above”, “above” or “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below” or “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0047] Unless otherwise defined, all technical and scientific terms used in the specification of the present invention have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in the specification of the present invention includes any and all combinations of one or more related listed items.

[0048] Combine the following Figure 1-Figure 8 The invention describes a tapping method and structure of a transformer wound with multiple flat copper wires.

[0049] like Figure 1 As shown, in one embodiment, a method for extracting taps from a transformer wound with multiple flat copper wires comprises the following steps:

[0050] Step S110, merging the taps of multiple strands of flat copper wires, and connecting a lead wire to the merged tap, where the lead wire is an enameled flat copper wire.

[0051] The ends of multiple parallel-wound or stacked enameled rectangular copper wires are used as taps, and the taps are combined, and a lead wire 310 is used to connect the combined taps, wherein the lead wire 310 can be a single enameled rectangular copper wire or a wire in multiple enameled rectangular copper wires. As an option, see Figure 2When multiple strands of enameled flat copper wire are wound together, a separate lead-out wire 310 is used to arrange the multiple flat copper wire taps 330 in parallel and keep the ends flush, wherein the parallel arrangement means that the flat sides of the multiple flat copper wires are on the same horizontal plane and the adjacent flat copper wire taps are against each other. Specifically, the multiple flat copper wire taps 330 are arranged in parallel so that the flat sides are flush, and the non-flat sides are against each other, and the end faces of the multiple flat copper wire taps 330 are kept flush, and the end of the lead-out wire 310 is superimposed on the taps of the multiple flat copper wires, and the axial direction of the lead-out wire 310 is perpendicular or approximately perpendicular to the axial direction of the tap. More specifically, the flat side of the end of the lead-out wire 310 is superimposed on the flat side of the multiple flat copper wire taps 330, and the end face of the lead-out wire 310 is flush with the non-flat side of the flat copper wire taps 330 arranged at the edge, and the non-flat side of the lead-out wire 310 is flush with the end face of the multiple flat copper wire taps 330.

[0052] Step S120, using argon arc welding to weld the lead-out wire and the combined tap connection, and after welding, quickly immersing the welded portion 320 in a coolant.

[0053] As an alternative, see Figure 4 or Figure 5 , immerse the weld 320 in the coolant for 5-10 minutes, then take it out to observe the welding effect and the temperature of the weld. The coolant is water contained in a container, and the coolant is replaced in time when the temperature of the coolant is high. The welding effect includes the degree of welding and the degree of flatness of the weld. The temperature of the weld can be judged according to the color of the weld and the evaporation rate of the coolant; when the temperature of the weld is higher than the preset temperature, immerse the weld 320 repeatedly in the coolant for 5-10 minutes until it is lower than the preset temperature, and observe the welding effect of the weld; when the welding effect reaches the standard, immerse the weld 320 in the coolant again until it reaches room temperature. The welding temperature of argon arc welding is usually between 2000 and 4000 degrees Celsius. The welding temperature is high, but the heat conduction along the welded object is slow. After welding, the weld 320 is quickly placed in the coolant, which can effectively avoid the damage of the enameled package caused by the heating of the flat copper wire tap, and reduce the area of ​​the enameled package damage.

[0054] Step S130, wrapping the cooled welded joint with H-grade glass fiber tape, and covering it with NOMEX insulating paperboard, and then fixing the NOMEX insulating paperboard with NOMEX tape.

[0055] After welding is completed, the weld 320 needs to be insulated. In order to avoid the adverse effects of burrs generated during welding on the insulation treatment, the weld 320 after cooling and drying needs to be polished with a file to remove the burrs, and then the weld 320 is wrapped with H-grade glass fiber tape. Figure 6Subsequently, two pieces of NOMEX insulating paperboard are clamped on both sides of the weld 320 and fixed with NOMEX tape, see Figure 7 After insulation treatment, measure the DC copper resistance to determine whether it meets the welding standards and to check whether there are any places that are not welded well. If the measured DC copper resistance is greater than the technical design value, check the welded joint 320. If it is serious, re-welding is required.

[0056] The tap lead-out method of the transformer wound with multiple flat copper wires in this embodiment combines the multiple flat copper wire taps 330 and then leads them out into a single lead-out wire 310 through argon arc welding, which can better adapt to the standard terminal hole. In addition, compared with tin welding, the welding joint of argon arc welding has greater rigidity, is less likely to produce cold welds and can withstand greater impact currents. The heat conduction of argon arc welding to the welded object is slow, and timely use of coolant to cool the weld 320 can effectively avoid damage to the enamel package caused by high temperature rise of the tap, thereby reducing the area of ​​enamel package damage.

[0057] like Figure 8 As shown, in one embodiment, the taps of multiple strands of flat copper wires are merged, and the lead wires are connected to the merged taps, including the following steps:

[0058] Step S810, when the enameled flat copper wires are wound in multiple strands, the tap of one of the strands is used as a lead wire, the taps of the remaining flat copper wires are stacked one by one, and the ends of the taps are exposed one by one, and the remaining flat copper wires are stacked on the one of the strands, see Figure 3 The flat copper wire taps expose part of the ends in sequence, which can increase the effective welding area of ​​adjacent taps during argon arc welding, reduce the welding difficulty and improve the mechanical strength after welding.

[0059] Step S820, adjust the length of the exposed ends of the remaining flat copper wires to be equal. Equal length means that the lengths are equal or approximately equal. The exposed ends of each flat copper wire in the remaining flat copper wires are equal in length, which can make the welded parts of the argon arc welding more evenly distributed, improve the flatness of the welded parts, reduce the generation of burrs, and help the insulation treatment after welding.

[0060] In this embodiment, argon arc welding is used to weld the lead-out wire and the combined tap connection, including:

[0061] According to the specifications of the flat copper wire, select the argon arc welding current and argon gas flow rate; control the argon arc welding to quickly weld the connection between the lead wire and the combined tap. In order to reduce the damage to the enameled package of the flat copper wire caused by the heat conduction generated during welding, the time of each welding should be shortened as much as possible, or after one welding, quickly enter the coolant to cool to room temperature and then weld again and cool again, and finally complete the argon arc welding by multiple cycles.

[0062] In addition, the present invention also provides a tap lead-out structure for a transformer wound with multiple flat copper wires.

[0063] like Figure 3 As shown, in one embodiment, a tap lead-out structure of a transformer wound with multiple flat copper wires includes a lead-out wire 310, a welding portion 320, and a tap 330 of multiple flat copper wires. The taps 330 of multiple flat copper wires are sequentially stacked or arranged in parallel, the welding portion 320 connects the taps 330 of multiple flat copper wires, and connects the lead-out wire 310 and the tap 330 of multiple flat copper wires, and the welding portion 320 is formed by argon arc welding.

[0064] The tap lead-out structure of the transformer wound with multiple flat copper wires in this embodiment combines the multiple flat copper wire taps 330 and connects them to a single lead-out wire 310 through a welded portion 320, which can be well adapted to a standard terminal hole. In addition, the welded portion 320 formed by argon arc welding has a relatively large rigidity, is not prone to cold welding, and can withstand a relatively large impact current. When the welded portion 320 is formed by argon arc welding, the argon arc welding has a relatively slow heat conduction to the welded object. The timely use of coolant to cool the welded portion can effectively avoid damage to the enamel package caused by the high temperature rise of the tap, and reduce the area of ​​the enamel package damage.

[0065] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0066] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A method for tapping a transformer wound with multiple flat copper wires, characterized in that: include: Merging the taps of multiple strands of flat copper wires, and connecting a lead wire to the merged tap, wherein the lead wire is an enameled flat copper wire; Use argon arc welding to weld the lead wire and the combined tap connection, and quickly immerse the weld in coolant after welding; After the weld is cooled, H-grade glass fiber tape is wrapped around it, and after covering it with the NOMEX insulating paperboard, the NOMEX insulating paperboard is fixed with the NOMEX tape.

2. The method for extracting the taps of a transformer wound with multiple flat copper wires according to claim 1, characterized in that: The method of combining the taps of the plurality of flat copper wires and connecting a lead wire to the combined taps comprises: When winding multiple strands of enameled flat copper wire, arrange the multiple strands of flat copper wire in parallel and keep the end faces flush; The end of the lead wire is superimposed on the tap of the multi-strand flat copper wire, and the axial direction of the lead wire is perpendicular to the axial direction of the tap.

3. The method for tapping a transformer wound with multiple flat copper wires according to claim 2, characterized in that: The method of superimposing the end of the lead-out wire on the tap of the multi-strand flat copper wire comprises: Overlay the flat side of the lead wire end onto the flat side of the multi-strand flat copper wire tap; The end face of the lead wire is flush with the non-flat side of the flat copper wire lead arranged at the edge, and the non-flat side of the lead wire is flush with the end face of the multi-strand flat copper wire lead.

4. The method for extracting the taps of a transformer wound with multiple flat copper wires according to claim 1, characterized in that: The method of merging the taps of the plurality of flat copper wires and connecting the lead wires to the merged taps comprises: When the enameled flat copper wires are wound in multiple strands, the tap of one of the flat copper wires is used as a lead wire, the taps of the remaining flat copper wires are stacked one by one, and the ends of the taps are exposed one by one, and the remaining flat copper wires are stacked on the one of the flat copper wires; Adjust the exposed ends of the remaining flat copper wires to equivalent lengths.

5. The method for extracting the taps of a transformer wound with multiple flat copper wires according to claim 3 or 4, characterized in that: The method of welding the lead-out wire and the combined tap connection by argon arc welding comprises: Select the current and argon gas flow rate of argon arc welding according to the specifications of the flat copper wire; Controlled argon arc welding is used to quickly weld the connection between the lead-out wire and the combined tap.

6. The method for extracting the taps of a transformer wound with multiple flat copper wires according to claim 5, characterized in that: The method of rapidly immersing the welded portion in a coolant after welding comprises: Immerse the weld in the coolant for 5-10 minutes, then take it out and observe the welding effect and temperature of the weld; When the temperature is higher than the preset temperature, immerse the welded joint repeatedly in the coolant for 5-10 minutes until it is lower than the preset temperature, and then observe the welding effect of the welded joint; When the welding effect reaches the standard, immerse the welded part in the coolant again until it reaches room temperature.

7. The method for extracting the taps of a transformer wound with multiple flat copper wires according to claim 6, characterized in that: After covering the NOMEX insulation paperboard, the NOMEX insulation paperboard is fixed with a NOMEX tape, including: Two pieces of NOMEX insulating paperboard are clamped on both sides of the weld and fixed with NOMEX tape.

8. The method for extracting the taps of a transformer wound with multiple flat copper wires according to claim 1, characterized in that: The step of wrapping the cooled welded joint with an H-grade glass fiber tape may also include: After the weld has cooled and dried, it is ground with a file to remove burrs.

9. The method for extracting the taps of a transformer wound with multiple flat copper wires according to claim 1, characterized in that: The method of fixing the NOMEX insulating paperboard with the NOMEX tape comprises: Measure the DC copper resistance to determine whether it meets the welding standards.

10. A tap lead structure for a transformer wound with multiple flat copper wires, characterized in that: The method for extracting taps of a transformer wound with multiple flat copper wires as claimed in any one of claims 1 to 9 comprises a lead-out wire, a welding portion and a tap of multiple flat copper wires, wherein the taps of multiple flat copper wires are sequentially stacked or arranged in parallel, the welding portion connects the stacked taps of multiple flat copper wires, and connects the lead-out wire and the tap of multiple flat copper wires, and the welding portion is formed by argon arc welding.

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