JP2009254027A - Brazing method of stator winding, brazing correction method of stator winding, and stator winding of rotating electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a brazing method which easily performs preplaced brazing between all brazing faces, and easily keep brazing intervals between element wires constant. <P>SOLUTION: The brazing method of the stator winding comprises: a first process which is a preparation step of obtaining element wire bundles of prescribed sizes by aligning a plurality of the hollow element wires composed of hollow wires, and bonds metal coatings on external peripheral faces of the hollow element wires in order to keep the intervals between the hollow element wires; and a second process in which a plurality of the element wire bundles obtained at the first process are sequentially laminated and inserted into a coolant feeding/discharging box having an opening in a state where a lid is removed, brazing materials are sandwiched between the element wire groups, between the element wire bundles and the coolant feeding/discharging box, and between the lid and the coolant feeding/discharging box, and a stator winding end is obtained by brazing the brazing materials between the element wires by raising a temperature to a brazing temperature in the atmosphere in a state where the lid is arranged at the opening of the coolant feeding/discharging box. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a solder supply / discharge box for simultaneously supplying / discharging a cooling medium and electrically energizing a cooling medium in an end portion of a direct cooling type rotating electric machine stator winding and a hollow wire constituting the winding. The present invention relates to an attaching method, a stator winding, and a stator winding repair method.

  As an example of a large turbine generator stator, as shown in FIG. 15, the conductor wire itself constituting the stator winding 22 inserted into the slot of the stator core 21 is formed of a hollow wire made of a hollow wire. However, there is a hollow wire that is directly cooled from the inside of the winding conductor through a coolant such as water.

  In order to supply and discharge the refrigerant directly to and from the coil element wire 23 made of a hollow element wire, as shown in FIG. Clip) 6 is provided. The refrigerant supply / discharge box 6 and the coil wire 23 are joined by inserting the coil wire 23 into the refrigerant supply / discharge box 6 having the opening 6a on one side of the bottomed rectangular tube shape, and then covering the opening 6a with the lid 7. The refrigerant supply / exhaust box 6, the lid (cover) 7 and the coil wire 23 are joined together by brazing at the same time.

In Patent Document 1, in the brazing of the end of the water-cooled large generator stator winding (stator coil) and the refrigerant supply / exhaust box 6, in order to maintain the brazing quality constant, A temperature sensor and a fiberscope are inserted into the pipe, and the temperature and the melting / flowing state of the brazing material are monitored to control the brazing temperature and the pressure of the brazing part. The oxygen concentration in the refrigerant supply / discharge box 6 is measured and managed.
JP-A-9-28062

  However, in Patent Document 1, this brazing with the refrigerant supply / exhaust box 6 is performed as shown in FIGS. 17 and 18, in which a strand bundle EB composed of a number of solid wires 1 and hollow wires 2 and a refrigerant are used. When there is a structural problem that the supply / discharge box 6 and the lid 7 are brazed at the same time, and the insertion position of the brazing material is often limited due to the configuration of the wire bundle EB, and cannot be placed between all brazing surfaces There are many. For this reason, it is easy to generate | occur | produce the part into which a brazing material does not enter easily between the strands in which it is difficult to install a brazing material.

  In many cases, such a defect cannot prevent the occurrence of a brazing defect even if the brazing state is monitored and the brazing condition is controlled according to the state as in Patent Document 1.

  An object of the present invention is to provide a method for brazing a stator winding and a brazing repair of a stator winding that can prevent close contact between the strands and prevent the occurrence of a defective portion where the brazing material does not enter when the strand is bundled. The object is to provide a method and a stator winding for a rotating electrical machine.

  In order to achieve the above object, the invention corresponding to claim 1 is a preparation for obtaining a bundle of strands having a predetermined size by arranging a plurality of hollow strands made of hollow wires, and maintaining a space between the hollow strands. A plurality of wire bundles obtained in the first step in a refrigerant supply / discharge box having a first step of attaching a metal coating to the outer peripheral surface of the hollow wire and an opening with the lid removed Are inserted in order, and a brazing material is sandwiched between the wire bundles, between the wire bundles and the refrigerant supply / exhaust box, and between the lid and the refrigerant supply / exhaust box, and the lid is attached to the opening of the refrigerant supply / exhaust box. And a second step of obtaining a stator winding end by brazing the brazing material between the strands by raising the temperature to a brazing temperature in the atmosphere in a provided state. This is a method of brazing a stator winding.

  In order to achieve the above object, the invention corresponding to claim 3 is a preparation for obtaining a bundle of strands having a predetermined size by alternately arranging hollow strands made of hollow wires and solid strands made of solid wires. An outer peripheral surface of the hollow strand facing the solid strand or an outer peripheral surface of the solid strand facing the hollow strand, the hollow strand, or an outer peripheral surface of the solid strand A plurality of wire bundles obtained in the first step are sequentially stacked and inserted into a refrigerant supply / discharge box having an opening with a lid removed, and a first step of attaching a metal coating for maintaining the interval In addition, a brazing material is sandwiched between the wire bundles, between the wire bundle and the refrigerant supply / discharge box, and between the lid and the refrigerant supply / discharge box, and the cover is provided at the opening of the refrigerant supply / discharge box. Second, obtaining a stator winding end by raising the temperature to the brazing temperature in the atmosphere and brazing the brazing material between the strands. A step, a brazing method of the stator winding, which comprises a.

  In order to achieve the above object, the invention corresponding to claim 5 is a preparation for obtaining a bundle of strands having a predetermined size by arbitrarily arranging a hollow strand made of a hollow wire and a solid strand made of a solid wire. A first step of adhering a metal coating for maintaining an interval between the hollow strands, the adjacent hollow strands of the solid strands, and the solid strands to an outer peripheral surface of the hollow strands; A plurality of strands obtained in the first step are sequentially stacked and stored in a refrigerant supply / discharge box having an opening with the lid removed, and between the strands, the strand bundle and the refrigerant supply / discharge A brazing material is sandwiched between boxes, the lid and the refrigerant supply / exhaust box, and the brazing material is heated to a brazing temperature in the atmosphere with the lid provided at the opening of the refrigerant supply / exhaust box. A second step of brazing between the strands to obtain a stator winding end, and a stator winding comprising: It is a method with cormorant.

  In order to achieve the above object, the invention corresponding to claim 10 is characterized in that at least a plurality of hollow wires made of hollow wires capable of supplying a refrigerant are arranged to form a bundle of strands of a predetermined size, and a plurality of one ends of each of the plurality of hollow wires In a stator winding of a rotating electrical machine having a stator winding end portion inserted and stacked, and brazed between the wire bundles and between the refrigerant supply / discharge box and the wire bundles, the refrigerant supply / discharge box is A stator winding of a rotating electrical machine, wherein a main part and a subordinate part are separable when repairing a brazing defect between the wire bundles.

  In order to achieve the above object, the invention corresponding to claim 11 is directed to a bundle of hollow wires having a predetermined size by arranging a plurality of hollow wires made of hollow wires in a refrigerant supply / discharge box having an opening with a lid removed. The hollow strands made of the hollow wires and the solid strands made of the solid solid wires are alternately or arbitrarily arranged, and a bundle of strands of a predetermined size is sequentially stacked and inserted between the bundles of strands, the strand bundle and the refrigerant supply / discharge A brazing material is sandwiched between boxes, the lid and the refrigerant supply / exhaust box, and the brazing material is heated to a brazing temperature in the atmosphere with the lid provided at the opening of the refrigerant supply / exhaust box. In a stator winding having a stator winding end brazed between each strand, a coating with a cold spray is applied to a brazing defect portion formed at a joint between the lid and the opening of the refrigerant supply / discharge box. This is a brazing repair method for the stator windings to be attached.

  According to the present invention, when a bundle of strands is formed, a stator winding brazing method and a stator winding brazing repair capable of preventing adhesion between the strands and preventing occurrence of a defective portion into which the brazing material does not enter. A method and a stator winding of a rotating electrical machine can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment of brazing method)
The first embodiment will be described with reference to FIGS. 1 to 4, 8, and 9. This is a method of brazing a stator winding that includes a first step and a second step described below. . In the first step, a hollow wire 2 made of a hollow wire as shown in FIGS. 1 and 3 and a solid wire 1 made of a solid wire as shown in FIGS. 3 and 4 are alternately arranged to have a predetermined size. Preparation for obtaining a bundle of strands EB, on the outer peripheral surface facing the solid strand 1 of the hollow strand 2 or on the outer peripheral surface facing the hollow strand 2 of the solid strand 1, Or the metal coating 3 for maintaining the space | interval with the outer peripheral surface of the solid strand 1 is adhered, and the outer peripheral surface facing the hollow strand 2 of the solid strand 1 or the solid strand 1 of the hollow strand 2 In this case, the brazing material coating 4 is attached to a position where it does not overlap the metal coating 3 attached to the outer peripheral surface of the hollow wire 2 or the solid wire 1.

  In the second step, a plurality of wire bundles EB obtained in the first step are sequentially stacked and inserted into a refrigerant supply / discharge box (clip) 6 having an opening with the lid 7 removed in FIG. 1, a brazing material, for example, a brazing filler metal 5 is sandwiched between the wire bundles EB, between the wire bundles EB and the refrigerant supply / exhaust box 6, and between the lid 7 and the refrigerant supply / exhaust box 6. In the state where the lid 7 is provided, the temperature is raised to the brazing temperature in the atmosphere, and the brazing material is brazed between the strands, and the stator winding end portion having the brazing portion 8 as shown in FIG. Is to get.

  According to the brazing method of the stator winding of the first embodiment, in the first step, as shown in FIG. 3, the outer peripheral surface or the solid strand facing the solid strand 1 of the hollow strand 2 as shown in FIG. By attaching a metal coating 3 for maintaining a distance from the outer peripheral surface of the hollow element wire 2 or the solid element wire 1 to the outer peripheral surface facing the hollow element wire 1, the conventional problem is solved. Can improve. Here, the conventional problems are often the structural problem of brazing a number of wire bundles EB and the refrigerant supply / discharge box 6 at the same time, and the insertion position of the brazing material is often limited due to the configuration of the wire bundle EB. The problem is that there are many cases where it cannot be placed between brazing surfaces. On the other hand, in the present embodiment, when the strands are made into the strand bundle EB, the close contact between the strands can be prevented, and the generation of a defective portion into which the brazing material does not enter can be prevented.

  The metal coating 3 may be a dot-like one as shown in (1), (2), (3) in the side view of FIG. 9, a linear one shown in (4), or a mixture thereof. Since the solid wire 1 and the hollow wire 2 are made of pure copper having good electrical conductivity, the metal coating 3 is also made of pure copper. However, the phosphor copper brazing material, or pure copper or phosphor copper brazing material, Other materials that do not produce hard and brittle compounds may be coated.

  The thickness of the metal coating 3 was set to 0.05 to 0.25 mm suitable for brazing phosphor copper brazing. When coating in a linear form, it is desirable not to disturb the flow of the brazing material during brazing. It is also possible to make the thickness of the metal coating 3 gradually thicker in a certain direction with respect to the longitudinal direction of the hollow wire 2. It is also possible to gradually increase the thickness of the hollow wire 2 in the height direction.

  If the gaps between the strands change regularly in a certain direction in this way, the flow of wax can be aligned from the narrower to the wider gaps.

  Then, as shown in FIGS. 1, 3, and 4, the brazing material coating 4 is attached to the outer peripheral surface of the solid wire 1. The brazing material coating 4 and the metal coating 3 are attached so as not to overlap when the solid wire 1 and the hollow wire 2 are bundled. Also, the brazing material coating 4 should not exceed the thickness of the metal coating 3. The metal coating 3 and the brazing material coating 4 are attached by cold spraying or thermal spraying to be described later.

  As shown in FIG. 1, the coated strands 1 and 2 are arranged in a line, alternately overlapped with the brazing filler metal 5, inserted into a refrigerant supply / discharge box (clip) 6, and pressed by a lid (cover) 7. As the sheet brazing material 5, a phosphor copper brazing material was used. When this is heated up to the brazing temperature of phosphor copper brazing in the atmosphere, the brazing material turns between the strands as shown in FIG.

  The first embodiment described above is a brazing method for obtaining a bundle of strands having a predetermined size by alternately arranging the hollow strands 2 and the solid strands 1, and this is modified as follows. Can be implemented. That is, the hollow strands 2 and the solid strands 1 can be arranged arbitrarily, not alternately, or can be similarly implemented even if only the hollow strands 2 are arranged without providing the solid strands 1. In the case of only the case, both the metal coating 3 and the brazing material coating 4 are formed on the outer peripheral surface of the hollow wire 2. In this case, the same effect as that of the above-described embodiment can be obtained.

  In addition, the brazing material coating 4 attached to the outer peripheral surfaces of the wires 1 and 2 in the above-described embodiment is not attached as shown in FIGS. 8 and 9 and only the metal coating 3 is applied to the outer peripheral surfaces of the wires 1 and 2. It may be attached.

  Next, as shown in FIGS. 5 and 6, a post-brazing coating 9 is attached to the surface of the brazed portion. As the coating material, pure copper or phosphor copper brazing material is suitable, but any material that does not corrode electrochemically with pure copper or phosphor copper brazing material in an underwater environment may be used. As a coating method, cold spraying and thermal spraying are suitable. The entire surface of the brazing part 8 may be covered with the coating 9 after brazing, or may be limited to a part where a brazing defect is generated or a part where a brazing defect is likely to occur. In addition, after the brazing coating 9 is adhered, it may be heated by high-frequency induction heating or the like to diffuse the adhered coating to further increase the adhesion.

  According to the present embodiment, since the metal coating 3 is attached to the solid wire 1, when the wire bundle EB is formed, the close contact between the wires can be prevented, and the occurrence of a defective portion where the brazing material does not enter can be prevented. . Moreover, since the space | interval between strands can be controlled by the thickness of the metal coating 3, it can be set as the thickness suitable for brazing and can make the inflow of the brazing material between strands favorable. Furthermore, since the gap between the strands can be gradually changed by changing the thickness of the metal coating 3, the flow of the molten brazing material can be controlled from the narrower to the wider gap, and by the inclusion of bubbles that are likely to occur during brazing. Generation of void defects can be prevented. Since the brazing material coating 4 is adhered between the strands, the brazing filler metal is called between the strands, and brazing defects between the strands are less likely to occur. Since these coatings 3 and 4 are performed by cold spraying, coating is easy. In addition, since the surface of the brazed portion after brazing is coated, even if a minute void defect or the like remains in the brazed portion 8, it can be covered with cooling water from the brazed portion. And leakage due to corrosion that occurs when water enters the microvoids can be prevented. Furthermore, since the coating is performed by cold spraying, the coating is easy and the adhesion is strong.

(Embodiment of stator winding)
Next, problems in the brazing will be described with reference to FIGS. 10, 11, and 12. In this brazing, not only between the wires, but also the brazing defect portion 10 is likely to occur in the brazing portion of the refrigerant supply / discharge box 6 and the lid 7. In some cases, cooling water permeates, the corrosion progresses, and water leaks from the brazed portion of the lid 7.

  For this reason, the refrigerant supply / discharge box 6 is a stator winding of a rotating electric machine configured to be separable into a main part and a subordinate part when repairing a brazing defect between the wire bundles EB. Specifically, as shown in FIGS. 11 and 12, a divided refrigerant supply / discharge box (divided clip) 14 is brazed to the refrigerant supply / discharge box 6 in a separable manner, and FIG. 11 shows the refrigerant supply / discharge box 6. And the state where the brazing surface between the clips of the divided refrigerant supply / exhaust box 14 is not brazed or both are separated. FIG. 12 shows a state in which the refrigerant supply / discharge box 6 and the divided refrigerant supply / discharge box 14 are brazed, and reference numeral 15 in FIG. 12 denotes an inter-clip brazing portion.

(Embodiment of brazing repair method)
On the other hand, in the case shown in FIG. 10, conventional TIG welding repair or brazing repair by high-frequency induction heating or burner heating has been performed, but since the material is copper and heat conduction is good, heat is easy to escape and difficult to repair. . Therefore, in this embodiment, the repair coating 11 of pure copper in FIG. 7B is attached to the brazing defect portion 10 in FIG. 7A using a cold gas spray system. Only the brazing defect portion 10 in FIG. 7B may be used, or the entire brazing portion in FIG. 7C may be coated. Further, after coating, the coating portion may be diffused by high-frequency induction heating or the like to further strengthen the adhesion. Heat brazing repair may be performed by attaching a brazing material.

  Here, the cold gas spray system used in the present invention will be described with reference to FIGS. This has a spray device main body 30, a carrier gas powder supply system, a process gas supply system for supplying helium gas and nitrogen gas, a nozzle 31, and a high-speed gas flow emitted from the nozzle 31. It has become. The spray device main body 30 includes a control panel 32, a heater 33, powder supply systems 35 and 36, an active jet heater 34, and the like. Metal powder is injected at high temperature (350 to 800 ° C.) and high pressure (3 to 4 MPa).

  In this embodiment, since the repair coating 11 is performed by a cold gas spray system, the repair is easy and the adhesion of the coating is excellent. It is also possible to carry in and repair the cold gas spray system at the place where the generator is installed.

  In the above-described embodiment, the stator winding is exemplified by a hollow wire made of a hollow wire and a solid wire made of a solid wire alternately arranged to obtain a wire bundle of a predetermined size. However, the present invention is not limited to this, only a hollow wire made of a hollow wire, or a hollow wire made of a hollow wire and a solid wire made of a solid wire are arbitrarily arranged to obtain a wire bundle of a predetermined size. Obviously, any of these may be used.

The front view which shows the state before brazing for demonstrating 1st Embodiment of the brazing method of the stator winding | coil in this invention. The front view which shows the state after brazing for demonstrating 2nd Embodiment of the brazing method of the stator winding | coil in this invention. The front view which shows a part of FIG. The side view which shows a part of FIG. The front view which shows the state before brazing for demonstrating 2nd Embodiment of the brazing method of the stator winding | coil in this invention. The front view which shows the state after brazing for demonstrating 2nd Embodiment of the brazing method of the stator winding | coil in this invention. The process figure for demonstrating the brazing repair method of the stator winding | coil in this invention. The front view which shows the state after brazing for demonstrating 3rd Embodiment of the brazing method of the stator winding | coil in this invention. The side view of FIG. The front view which shows the state after brazing for demonstrating the modification of the brazing method of the stator winding | coil in this invention. The front view which shows the state after brazing for demonstrating the modification of the brazing method of the stator winding | coil in this invention. The front view which shows the state after brazing for demonstrating the modification of the brazing method of the stator winding | coil in this invention. The schematic block diagram for demonstrating the cold gas spray system used in order to implement the method of this invention. The block diagram for demonstrating the cold gas spray system used in order to implement this invention method. The schematic block diagram which shows only the upper half part of the stator winding | coil which is the object of this invention. The perspective view for demonstrating the brazing method of the conventional stator winding | coil. The front view which is for demonstrating the brazing method of the conventional stator winding | winding, and shows the state before brazing. The front view which is for demonstrating the brazing method of the conventional stator winding | winding, and shows the state after brazing.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Solid wire strand, 2 ... Hollow wire strand, 3 ... Metal coating, 4 ... Brazing material coating, 5 ... Plate brazing material, 6 ... Refrigerant supply / discharge box (clip), 6a ... Opening, 7 ... Cover ( Cover), 8 ... brazing part, 9 ... coating after brazing, 10 ... defective part of brazing, 11 ... repair coating, 14 ... divided refrigerant supply / discharge box, 21 ... stator core, 22 ... stator winding, 23 DESCRIPTION OF SYMBOLS ... Coil strand, 30 ... Sprayer main body, 31 ... Nozzle, 32 ... Control panel, 33 ... Heater, 34 ... Active jet heater, 35, 36 ... Powder supply system.

Claims (11)

A preparation for obtaining a bundle of strands having a predetermined size by arranging a plurality of hollow strands made of hollow wires, wherein a metal coating for keeping a space between the hollow strands is attached to an outer peripheral surface of the hollow strands. 1 process,
A plurality of wire bundles obtained in the first step are sequentially stacked and inserted into a refrigerant supply / discharge box having an opening with the lid removed, and the wire bundles and the refrigerant supply / discharge box are placed between the wire bundles. In the meantime, a brazing material is sandwiched between the lid and the refrigerant supply / exhaust box, and the brazing material is heated to a brazing temperature in the atmosphere with the lid provided at the opening of the refrigerant supply / exhaust box. A second step of brazing between the strands to obtain a stator winding end;
A method of brazing a stator winding, comprising: A preparation for obtaining a bundle of strands of a predetermined size by arranging a plurality of hollow strands made of hollow wires, and attaching a metal coating for maintaining a space between the hollow strands to the outer peripheral surface of the hollow strands, A first step of attaching a brazing material coating to a position of the outer peripheral surface of the hollow strand that does not overlap with the metal coating attached to the outer peripheral surface of the hollow strand;
A plurality of wire bundles obtained in the first step are sequentially stacked and inserted into a refrigerant supply / discharge box having an opening with the lid removed, and the wire bundles and the refrigerant supply / discharge box are placed between the wire bundles. In the meantime, a brazing material is sandwiched between the lid and the refrigerant supply / exhaust box, and the brazing material is heated to a brazing temperature in the atmosphere with the lid provided at the opening of the refrigerant supply / exhaust box. A second step of brazing between the strands to obtain a stator winding end;
A method of brazing a stator winding, comprising: It is a preparation for obtaining a bundle of strands of a predetermined size by alternately arranging hollow strands made of hollow wires and solid strands made of solid solid wires, and an outer peripheral surface of the hollow strands facing the solid strands Or a first step of attaching a metal coating for keeping a space between the hollow element wire or the outer peripheral surface of the solid element wire to an outer peripheral surface of the solid element wire facing the hollow element wire; ,
A plurality of wire bundles obtained in the first step are sequentially stacked and inserted into a refrigerant supply / discharge box having an opening with the lid removed, and the wire bundles and the refrigerant supply / discharge box are placed between the wire bundles. In the meantime, a brazing material is sandwiched between the lid and the refrigerant supply / discharge box, and the temperature of the brazing material is raised to the brazing temperature in the atmosphere with the cover provided at the opening of the refrigerant supply / discharge box. A second step of brazing between the strands to obtain a stator winding end;
A method of brazing a stator winding, comprising: It is a preparation for obtaining a bundle of strands of a predetermined size by alternately arranging hollow strands made of hollow wires and solid strands made of solid solid wires, and an outer peripheral surface of the hollow strands facing the solid strands Alternatively, the solid element wire is attached to the outer peripheral surface of the solid element wire facing the hollow element wire so as to maintain a distance from the outer peripheral surface of the hollow element wire or the solid element wire. The outer peripheral surface of the hollow element wire or the solid element wire of the hollow element wire that is opposed to the metal coating attached to the outer surface of the hollow element wire or the solid element wire A first step of depositing a brazing filler metal coating;
A plurality of wire bundles obtained in the first step are sequentially stacked and inserted into a refrigerant supply / discharge box having an opening with the lid removed, and the wire bundles and the refrigerant supply / discharge box are placed between the wire bundles. In the meantime, a brazing material is sandwiched between the lid and the refrigerant supply / discharge box, and the temperature of the brazing material is raised to the brazing temperature in the atmosphere with the cover provided at the opening of the refrigerant supply / discharge box. A second step of brazing between the strands to obtain a stator winding end;
A method of brazing a stator winding, comprising: A hollow strand made of a hollow wire and a solid strand made of a solid solid wire are arbitrarily arranged to obtain a wire bundle of a predetermined size, and the hollow wire and the solid wire are adjacent to each other. A first step of attaching a metal coating for maintaining a space between the hollow strand and the solid strand to the outer peripheral surface of the hollow strand;
A plurality of wire bundles obtained in the first step are sequentially stacked and stored in a refrigerant supply / discharge box having an opening with the lid removed, and between the wire bundles, the wire bundle and the refrigerant supply / discharge box. In the meantime, a brazing material is sandwiched between the lid and the refrigerant supply / exhaust box, and the brazing material is heated to a brazing temperature in the atmosphere with the lid provided at the opening of the refrigerant supply / exhaust box. A second step of brazing between the strands to obtain a stator winding end;
A method of brazing a stator winding, comprising: It is a preparation for obtaining a bundle of strands having a predetermined length by arbitrarily arranging a hollow strand made of a hollow wire and a solid strand made of a solid solid wire, which are adjacent to each other among the hollow strand and the solid strand. A metal coating for maintaining a space between the hollow strand and the solid strand is attached to an outer peripheral surface of the hollow strand, and the hollow strand of the solid strand or the solid of the hollow strand A first step of attaching a brazing material coating to a position that is an outer peripheral surface facing the element wire and does not overlap a metal coating that is attached to the outer peripheral surface of the hollow element wire or the solid element wire;
A plurality of wire bundles obtained in the first step are sequentially stacked and stored in a refrigerant supply / discharge box having an opening with the lid removed, and between the wire bundles, the wire bundle and the refrigerant supply / discharge box. In the meantime, a brazing material is sandwiched between the lid and the refrigerant supply / discharge box, and the temperature of the brazing material is raised to the brazing temperature in the atmosphere with the cover provided at the opening of the refrigerant supply / discharge box. A second step of brazing between the strands to obtain a stator winding end;
A method of brazing a stator winding, comprising:   A third step of attaching a corrosion-resistant coating to the surface of the brazed portion of the refrigerant supply / discharge box and the lid, which is the stator winding end obtained in the second step; The method for brazing a stator winding according to any one of claims 1 to 6, further comprising:   The method of brazing a stator winding according to any one of claims 1 to 6, wherein the metal coating and / or the brazing material coating is attached by means of spraying powder.   In a state where the lid is provided at the opening of the refrigerant supply / discharge box, a cold spray is applied to a joint portion between the lid and the opening of the refrigerant supply / discharge box or a brazing defect portion of the cover and the refrigerant supply / discharge box. The method of brazing a stator winding according to any one of claims 1 to 6, further comprising a step of depositing a coating. At least a plurality of hollow wires made of hollow wires capable of supplying a refrigerant are arranged side by side, and a plurality of wire bundles of a predetermined size are inserted into a refrigerant supply / discharge box, and one end of each of the plurality of hollow strands is inserted into the refrigerant supply / discharge box. In a stator winding of a rotating electric machine having a stator winding end brazed between a box and the wire bundle,
A stator winding of a rotating electrical machine, wherein the refrigerant supply / discharge box is configured to be separable into a main part and a subordinate part when repairing a brazing defect between the wire bundles. A plurality of hollow wires made of hollow wires are arranged in a refrigerant supply / discharge box having an opening with the lid removed, and a solid wire bundle of a predetermined size or a hollow wire made of the hollow wire and a solid wire made of the solid wire. A strand of wires having a predetermined size is sequentially stacked and inserted by alternately or arbitrarily arranging the strands, and brazing material is inserted between the strands of the wire, between the strand of bundles and the refrigerant supply / discharge box, and between the lid and the refrigerant supply / discharge box. A stator winding end portion that sandwiches and brazes the brazing material between the strands by raising the temperature to a brazing temperature in the atmosphere with the lid provided on the opening of the refrigerant supply / discharge box In the stator winding,
A stator winding brazing repair method in which a coating is applied to a brazing defect portion formed at a joint portion between the lid and the refrigerant supply / discharge box with a cold spray.

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