Processing method and application of pumped storage air internal cooling magnetic pole coil copper bar

Abstract

This invention discloses a method for processing copper busbars for pumped-storage internal cooling magnetic pole coils and its application, belonging to the technical field of pumped-storage generator motors. The method includes the following steps: S1, processing a tool blank, on which grooves adapted to the copper busbar are machined, one end of the groove being an open end and the other end a closed end; S2, machining multiple tool notches along the length of the tool blank, corresponding to the notches on the copper busbar; S3, installing multiple pressure strips along the length of the tool blank, placing the copper busbar into the grooves of the tool blank, and pressing the copper busbar tightly with the pressure strips; S4, placing the tool blank and the copper busbar together on a milling machine for milling the notches on the copper busbar. This invention, by using a tool blank to precisely position and process the notches on the copper busbar, can ensure the cooling effect of the magnetic pole coil while guaranteeing the structural strength and operational stability of the copper busbar.

Description

Technical Field

[0001] This invention relates to the field of pumped storage power generation motor technology, and in particular to a method for processing copper busbars of internal cold magnetic pole coils in pumped storage power generation and its application. Background Technology

[0002] Pumped storage generator motors operate at high speeds and generate significant centrifugal force. To achieve lightweight design, a method of internal and external cooling of the rotor poles is adopted to improve rotor cooling capacity, thereby reducing the amount of copper busbars used in the poles and reducing the rotor diameter, thus fundamentally reducing centrifugal force.

[0003] The rotor magnetic pole coils of large pumped storage generator motors generally adopt a spiral stacked structure with multiple turns of copper busbars welded together. High-strength insulating paper containing insulating adhesive is placed between the turns to ensure the insulation between the turns.

[0004] To improve the cooling effect of the magnetic pole coil, ventilation channels are usually created within the copper busbar of the magnetic pole coil by creating openings. However, for the centripetal magnetic poles used in large pumped-storage generators, the magnetic pole coils can only use thin copper busbars that are easy to bend into an arc shape, with a thickness of only 4-8mm. If openings are to be made in the copper busbar, the height of the opening needs to reach a certain value to ensure smooth ventilation. According to engineering experience and calculation analysis, it needs to be at least close to 3mm high. This would leave the remaining structural thickness of the copper busbar at the opening very small, greatly weakening its load-bearing capacity. Taking a 6mm thick magnetic pole copper busbar as an example, after machining a 3mm hole, the remaining structure of the copper busbar at this point is two thin sheets with a thickness of only 1.5mm, which may lead to the copper busbar breaking. In addition, it is also very difficult to manufacture ventilation holes that are too small in the middle of the copper busbar.

[0005] Therefore, for the above-mentioned magnetic pole coil, it is proposed to process notches at the same position on adjacent copper busbars, then weld them into a spiral stack, insert insulation, and shape them. The two notches at the same position interlock to form an internal cooling ventilation hole.

[0006] However, the precision of the ventilation hole alignment has a decisive impact on the ventilation effect and the appearance quality of the magnetic pole products. Since the long-side copper busbars of the rotor magnetic pole coils of large pumped-storage generator motors, which have internal cooling ventilation channels, can generally reach lengths of over 3 meters, multiple notches are usually required to significantly improve the cooling effect, sometimes reaching dozens. During the processing, current methods require very expensive giant milling machines due to the excessive length of the copper busbars. While this allows for relatively precise machining, each notch needs to be machined using the short edge of the copper busbar as a reference to eliminate accumulated errors. However, due to the excessive length, the precision error of the machine tool guide rails also accumulates, resulting in poorer positioning accuracy for notches farther from the reference. When subsequent adjacent copper busbars are aligned, because they are spirally stacked, the same reference edge as the machining reference is often used to ensure post-welding precision—that is, the short edge of the copper busbar serving as the machining reference. This results in adjacent copper busbars being aligned in opposite directions, and the error of the far-end notch will exacerbate the error after alignment. Furthermore, giant machine tools are scarce and often used to process large components. Using them to process copper busbars would consume production resources. If small or medium-sized machine tools are used, the copper busbar clamping needs to be readjusted during processing, making it impossible to use a single processing reference. While the initial few notches can be aligned using the end of the copper busbar as a reference, subsequent notches must be aligned using the already machined notches, easily leading to cumulative errors. Additionally, thin copper busbars cannot be magnetically clamped; multiple pressure plates are typically distributed along the length of the busbar. If multiple clamping and alignment operations are used, the copper busbar may experience clamping variations and deflection deformation, causing additional errors. Trial processing verification shows that the positioning and processing error of a single notch can be guaranteed to be within 0.1mm, but after processing dozens of notches, the maximum positional error can reach 1mm or even several millimeters. Combined with the unavoidable errors in subsequent welding and pressing processes, this can result in an error of several millimeters at the edge of the notch.

[0007] Chinese patent document CN102069252A, published on May 25, 2011, discloses a method for manufacturing a magnetic pole coil, characterized in that: (1) First, install the clamping and positioning device on the brazing machine and adjust its position. Check whether the power supply is on and whether the cooling system is running normally. (2) Place a welding plate between the two copper busbars and place the copper busbars to be welded on the center position of the induction coil. Adjust the horizontal adjustment plate to ensure that the U-shaped pressure head is directly facing the center position of the induction coil. After adjustment, operate the movable handle to press the U-shaped pressure head tightly onto the two copper busbars to be welded. (3) After adjusting the position of the horizontal U-shaped pressure head, clamp the workpiece to ensure that it remains in the same position and keep the clamping force in a balanced state; (4) Power on the high frequency induction power supply of the high frequency brazing machine to make the induction coil heat the weld joint and the welding piece of the two copper busbars. When the weld joint and the welding piece reach the melting state, cut off the power supply of the induction coil. At this time, maintain the clamping force for 3-5 seconds. The welding piece is quickly solidified by the cooling cycle inside the U-shaped pressure head. After the welding piece solidifies, open the clamping and positioning device to complete the production of the magnetic pole coil.

[0008] The magnetic pole coil manufacturing method disclosed in this patent document overcomes the defects caused by uneven dissolution of silver solder or poor soldering in the welding of copper busbars, resulting in short circuits between turns and improving welding efficiency and quality. However, since there are no ventilation holes on the copper busbar, the cooling effect of the magnetic pole coil is poor. If ventilation holes are made on the copper busbar, the remaining structural thickness of the copper busbar at the ventilation hole is very small, which greatly weakens its load-bearing capacity, reduces structural strength, and affects the stability of use. Summary of the Invention

[0009] In order to overcome the defects of the prior art, this invention provides a method and application for processing copper busbars of pumped storage air-cooled magnetic pole coils. This invention uses a tool to accurately locate and process the notches on the copper busbar, which can ensure the cooling effect of the magnetic pole coil while ensuring the structural strength and stability of the copper busbar.

[0010] This invention is achieved through the following technical solution: A method for processing copper busbars for internal cold magnetic pole coils in pumped hydro storage includes the following steps: S1. Machining tool blank: Machining a groove on the tool blank that matches the copper busbar. One end of the groove is an open end, and the other end of the groove is a closed end. S2. Machining tool notches that are consistent with the notches on the copper busbars along the length of the tool blank; there are multiple tool notches. S3. Install multiple pressure strips along the length of the tool holder, insert the copper busbar into the groove of the tool holder, and press the copper busbar tightly with the pressure strips; S4. Place the tool holder and the copper busbar together on the milling machine to mill the notch of the copper busbar.

[0011] In S1, the straightness of the groove is 0.1 mm / m.

[0012] In S1, the flatness of the groove is 0.2 mm per meter along its length.

[0013] In S1, there are one or more grooves. When there are multiple grooves, any two grooves are parallel to each other.

[0014] In S2, setting tool notches that are consistent with copper busbar notches means that the number, width, and position of tool notches are the same as those of copper busbar notches.

[0015] The tool notches are all based on the width of the unopened groove, with a positional tolerance of 0.05mm.

[0016] In S3, the copper busbar is formed by water seal extrusion, and after the width side is precision machined, the perpendicularity between the width side and the long side of the copper busbar is 0.05mm.

[0017] In S3, installing multiple pressure strips along the length of the tool carriage means machining multiple threaded holes along the length of the tool carriage, with a spacing of 200mm between any two adjacent threaded holes, and then attaching pressure strips to the threaded holes.

[0018] In S3, a felt cloth is adhered to the pressure strip, and the felt cloth is located between the pressure strip and the copper busbar. The size of the felt cloth is the same as the size of the pressure strip.

[0019] In S4, the milling process uses slow milling.

[0020] In S4, the milling of the copper busbar notch refers to the re-alignment and machining based on the tool notch, and the milling tool mark is less than 0.02mm.

[0021] An application of a copper busbar for a pumped-storage air-cooled magnetic pole coil, applicable to pumped-storage air-cooled magnetic pole coils.

[0022] The beneficial effects of this invention are mainly reflected in the following aspects: 1. Compared with the prior art, the present invention uses a tool to accurately locate and process the notch on the copper busbar, which can ensure the cooling effect of the magnetic pole coil while ensuring the structural strength and stability of the copper busbar. 2. In this invention, the copper busbar is pressed into the groove of the tool holder by a pressure strip, so that the copper busbar can remain flat and avoid affecting the positional accuracy of the copper busbar notch due to local warping of the copper busbar.

[0023] 3. In this invention, there are one or more grooves. When there are multiple grooves, any two grooves are parallel to each other. By setting multiple grooves side by side on the tool holder, multiple copper busbars can be clamped at the same time. The copper busbar notches of all the side by side can be processed at one time using the same tool notch of the tool holder, which can ensure positioning accuracy and improve processing efficiency.

[0024] 4. This invention can achieve the processing of copper busbar notches in a large number of copper busbars using conventional small and medium-sized machine tools, and has good applicability and economy.

[0025] 5. This invention achieves precise positioning of the copper busbar notch through a tool holder, which can solve the cumulative error caused by the multi-reference positioning problem in small and medium-sized machine tools, and also avoid the cumulative error introduced by the guide rails in giant machine tools.

[0026] 6. In this invention, a felt cloth is bonded to the pressure strip, and the felt cloth is located between the pressure strip and the copper busbar. The size of the felt cloth is the same as the size of the pressure strip, which can prevent the surface of the copper busbar from being excessively squeezed by the pressure strip and is beneficial to protect the surface of the copper busbar during processing.

[0027] 7. In this invention, the milling process uses slow milling, which can ensure that the copper busbar does not warp severely due to stress release after processing, thus ensuring processing quality.

[0028] 8. This invention achieves one-time clamping and reliable fixing of copper busbars by specifically setting grooves, tool notches and pressure strips on the tool jig, and achieves accurate positioning of copper busbar notches. It effectively ensures the positional accuracy, shape consistency and processing efficiency of multi-copper busbar notch processing, and is particularly suitable for high-precision and mass production of copper busbars for air-cooled magnetic pole coils in pumped storage motors. Attached Figure Description

[0029] The present invention will now be further described in detail with reference to the accompanying drawings and specific embodiments, wherein: Figure 1 This is a schematic diagram of the structure of the tool tire of the present invention; Figure 2 This is a schematic diagram of the copper busbar structure of the present invention; Figure 3 This is a schematic diagram of the structure of the pressure strip of the present invention; The markings in the diagram are: 1. Tool blank, 2. Copper busbar, 3. Groove, 4. Copper busbar notch, 5. Tool notch, 6. Pressure strip, 7. Felt cloth. Detailed Implementation

[0030] Example 1 See Figure 1 A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems includes the following steps: S1. Machining tool 1, machining a groove 3 on tool 1 that is compatible with copper busbar 2, one end of groove 3 is an open end and the other end of groove 3 is a closed end; S2. A tool notch 5, which is consistent with the copper busbar notch 4, is machined along the length direction of the tool fixture 1. There are multiple tool notches 5. S3. Install multiple pressure strips 6 along the length of the tool fixture 1, place the copper busbar 2 into the groove 3 of the tool fixture 1, and press the copper busbar 2 tightly by the pressure strips 6; S4. Place the tool holder 1 together with the copper busbar 2 on the milling machine to mill the notch 4 of the copper busbar.

[0031] This embodiment is the most basic implementation method. Compared with the prior art, by using the tool 1 to accurately position and process the copper busbar notch 4 on the copper busbar 2, the cooling effect of the magnetic pole coil can be ensured while guaranteeing the structural strength and stability of the copper busbar 2. Example 2 See Figure 1 and Figure 2 A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems includes the following steps: S1. Machining tool 1, machining a groove 3 on tool 1 that is compatible with copper busbar 2, one end of groove 3 is an open end and the other end of groove 3 is a closed end; S2. A tool notch 5, which is consistent with the copper busbar notch 4, is machined along the length direction of the tool fixture 1. There are multiple tool notches 5. S3. Install multiple pressure strips 6 along the length of the tool fixture 1, place the copper busbar 2 into the groove 3 of the tool fixture 1, and press the copper busbar 2 tightly by the pressure strips 6; S4. Place the tool holder 1 together with the copper busbar 2 on the milling machine to mill the notch 4 of the copper busbar.

[0032] In S1, the straightness of the groove 3 is 0.1 mm / m.

[0033] In S1, the flatness of the groove 3 within each meter along its length is 0.2 mm.

[0034] This embodiment is a preferred implementation. The copper busbar 2 is pressed into the groove 3 of the tool holder 1 by the pressure strip 6, so that the copper busbar 2 can remain flat and avoid affecting the positional accuracy of the copper busbar notch 4 due to local warping of the copper busbar 2.

[0035] Example 3 See Figure 1 and Figure 2 A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems includes the following steps: S1. Machining tool 1, machining a groove 3 on tool 1 that is compatible with copper busbar 2, one end of groove 3 is an open end and the other end of groove 3 is a closed end; S2. A tool notch 5, which is consistent with the copper busbar notch 4, is machined along the length direction of the tool fixture 1. There are multiple tool notches 5. S3. Install multiple pressure strips 6 along the length of the tool fixture 1, place the copper busbar 2 into the groove 3 of the tool fixture 1, and press the copper busbar 2 tightly by the pressure strips 6; S4. Place the tool holder 1 together with the copper busbar 2 on the milling machine to mill the notch 4 of the copper busbar.

[0036] In S1, the straightness of the groove 3 is 0.1 mm / m.

[0037] In S1, the flatness of the groove 3 within each meter along its length is 0.2 mm.

[0038] In S1, there are multiple grooves 3, and any two grooves 3 are parallel to each other.

[0039] In S2, setting tool notches 5 that are the same as copper busbar notches 4 means that the number, width, and position of tool notches 5 are the same as those of copper busbar notches 4.

[0040] This embodiment is another preferred implementation. There are multiple grooves 3, and any two grooves 3 are parallel to each other. By setting multiple grooves 3 side by side on the tool holder 1, multiple copper busbars 2 can be clamped at the same time. The copper busbar notches 4 of all the side by side copper busbars 2 can be processed at one time using the same tool notch 5 of the tool holder 1, which can ensure positioning accuracy and improve processing efficiency.

[0041] Example 4 See Figure 1 and Figure 2 A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems includes the following steps: S1. Machining tool 1, machining a groove 3 on tool 1 that is compatible with copper busbar 2, one end of groove 3 is an open end and the other end of groove 3 is a closed end; S2. A tool notch 5, which is consistent with the copper busbar notch 4, is machined along the length direction of the tool fixture 1. There are multiple tool notches 5. S3. Install multiple pressure strips 6 along the length of the tool fixture 1, place the copper busbar 2 into the groove 3 of the tool fixture 1, and press the copper busbar 2 tightly by the pressure strips 6; S4. Place the tool holder 1 together with the copper busbar 2 on the milling machine to mill the notch 4 of the copper busbar.

[0042] In S1, the straightness of the groove 3 is 0.1 mm / m.

[0043] In S1, the flatness of the groove 3 within each meter along its length is 0.2 mm.

[0044] In S1, there are multiple grooves 3, and any two grooves 3 are parallel to each other.

[0045] In S2, setting tool notches 5 that are the same as copper busbar notches 4 means that the number, width, and position of tool notches 5 are the same as those of copper busbar notches 4.

[0046] The tool notch 5 is based on the unopened width edge of the groove 3, with a positional tolerance of 0.05mm.

[0047] In S3, the copper busbar 2 is formed by water seal extrusion, and after the width side is finely machined, the perpendicularity between the width side and the long side of the copper busbar 2 is 0.05mm.

[0048] This embodiment is another preferred implementation method. It can be used with conventional small and medium-sized machine tools to process a large number of copper busbars 2 copper busbar notches 4, which has good applicability and economy.

[0049] The precise positioning of the copper busbar notch 4 is achieved by using tool kit 1, which can solve the cumulative error caused by the multi-reference positioning problem of small and medium-sized machine tools, and also avoid the cumulative error introduced by the guide rail when using giant machine tools.

[0050] Example 5 See Figures 1-3 A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems includes the following steps: S1. Machining tool 1, machining a groove 3 on tool 1 that is compatible with copper busbar 2, one end of groove 3 is an open end and the other end of groove 3 is a closed end; S2. A tool notch 5, which is consistent with the copper busbar notch 4, is machined along the length direction of the tool fixture 1. There are multiple tool notches 5. S3. Install multiple pressure strips 6 along the length of the tool fixture 1, place the copper busbar 2 into the groove 3 of the tool fixture 1, and press the copper busbar 2 tightly by the pressure strips 6; S4. Place the tool holder 1 together with the copper busbar 2 on the milling machine to mill the notch 4 of the copper busbar.

[0051] In S1, the straightness of the groove 3 is 0.1 mm / m.

[0052] In S1, the flatness of the groove 3 within each meter along its length is 0.2 mm.

[0053] In S1, there are multiple grooves 3, and any two grooves 3 are parallel to each other.

[0054] In S2, setting tool notches 5 that are the same as copper busbar notches 4 means that the number, width, and position of tool notches 5 are the same as those of copper busbar notches 4.

[0055] The tool notch 5 is based on the unopened width edge of the groove 3, with a positional tolerance of 0.05mm.

[0056] In S3, the copper busbar 2 is formed by water seal extrusion, and after the width side is finely machined, the perpendicularity between the width side and the long side of the copper busbar 2 is 0.05mm.

[0057] In S3, installing multiple pressure strips 6 in the length direction of tool kit 1 means machining multiple threaded holes in the length direction of tool kit 1, with the distance between any two adjacent threaded holes being 200mm, and then attaching pressure strips 6 to the threaded holes.

[0058] In S3, a felt cloth 7 is adhered to the pressure strip 6. The felt cloth 7 is located between the pressure strip 6 and the copper busbar 2, and the size of the felt cloth 7 is the same as the size of the pressure strip 6.

[0059] This embodiment is another preferred implementation. A felt cloth 7 is adhered to the pressure strip 6. The felt cloth 7 is located between the pressure strip 6 and the copper busbar 2. The size of the felt cloth 7 is the same as that of the pressure strip 6, which can prevent the surface of the copper busbar 2 from being excessively squeezed by the pressure strip 6, and is beneficial to protect the surface of the copper busbar 2 during processing.

[0060] Example 6 See Figures 1-3 A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems includes the following steps: S1. Machining tool 1, machining a groove 3 on tool 1 that is compatible with copper busbar 2, one end of groove 3 is an open end and the other end of groove 3 is a closed end; S2. A tool notch 5, which is consistent with the copper busbar notch 4, is machined along the length direction of the tool fixture 1. There are multiple tool notches 5. S3. Install multiple pressure strips 6 along the length of the tool fixture 1, place the copper busbar 2 into the groove 3 of the tool fixture 1, and press the copper busbar 2 tightly by the pressure strips 6; S4. Place the tool holder 1 together with the copper busbar 2 on the milling machine to mill the notch 4 of the copper busbar.

[0061] In S1, the straightness of the groove 3 is 0.1 mm / m.

[0062] In S1, the flatness of the groove 3 within each meter along its length is 0.2 mm.

[0063] In S1, there are multiple grooves 3, and any two grooves 3 are parallel to each other.

[0064] In S2, setting tool notches 5 that are the same as copper busbar notches 4 means that the number, width, and position of tool notches 5 are the same as those of copper busbar notches 4.

[0065] The tool notch 5 is based on the unopened width edge of the groove 3, with a positional tolerance of 0.05mm.

[0066] In S3, the copper busbar 2 is formed by water seal extrusion, and after the width side is finely machined, the perpendicularity between the width side and the long side of the copper busbar 2 is 0.05mm.

[0067] In S3, installing multiple pressure strips 6 in the length direction of tool kit 1 means machining multiple threaded holes in the length direction of tool kit 1, with the distance between any two adjacent threaded holes being 200mm, and then attaching pressure strips 6 to the threaded holes.

[0068] In S3, a felt cloth 7 is adhered to the pressure strip 6. The felt cloth 7 is located between the pressure strip 6 and the copper busbar 2, and the size of the felt cloth 7 is the same as the size of the pressure strip 6.

[0069] In S4, the milling process uses slow milling.

[0070] This embodiment is another preferred implementation. The milling process uses slow milling, which can ensure that after the copper busbar 2 is processed, it avoids severe warping of the copper busbar 2 due to stress release, thus ensuring the processing quality.

[0071] Example 7 See Figures 1-3 A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems includes the following steps: S1. Machining tool 1, machining a groove 3 on tool 1 that is compatible with copper busbar 2, one end of groove 3 is an open end and the other end of groove 3 is a closed end; S2. A tool notch 5, which is consistent with the copper busbar notch 4, is machined along the length direction of the tool fixture 1. There are multiple tool notches 5. S3. Install multiple pressure strips 6 along the length of the tool fixture 1, place the copper busbar 2 into the groove 3 of the tool fixture 1, and press the copper busbar 2 tightly by the pressure strips 6; S4. Place the tool holder 1 together with the copper busbar 2 on the milling machine to mill the notch 4 of the copper busbar.

[0072] In S1, the straightness of the groove 3 is 0.1 mm / m.

[0073] In S1, the flatness of the groove 3 within each meter along its length is 0.2 mm.

[0074] In S1, there are multiple grooves 3, and any two grooves 3 are parallel to each other.

[0075] In S2, setting tool notches 5 that are the same as copper busbar notches 4 means that the number, width, and position of tool notches 5 are the same as those of copper busbar notches 4.

[0076] The tool notch 5 is based on the unopened width edge of the groove 3, with a positional tolerance of 0.05mm.

[0077] In S3, the copper busbar 2 is formed by water seal extrusion, and after the width side is finely machined, the perpendicularity between the width side and the long side of the copper busbar 2 is 0.05mm.

[0078] In S3, installing multiple pressure strips 6 in the length direction of tool kit 1 means machining multiple threaded holes in the length direction of tool kit 1, with the distance between any two adjacent threaded holes being 200mm, and then attaching pressure strips 6 to the threaded holes.

[0079] In S3, a felt cloth 7 is adhered to the pressure strip 6. The felt cloth 7 is located between the pressure strip 6 and the copper busbar 2, and the size of the felt cloth 7 is the same as the size of the pressure strip 6.

[0080] In S4, the milling process uses slow milling.

[0081] In S4, the milling of the copper busbar notch 4 refers to the re-alignment and machining based on the tool notch 5, and the milling tool marks are less than 0.02mm.

[0082] This embodiment is the best implementation method. By specifically setting grooves 3, tool notches 5 and pressure strips 6 on the tool jig 1, the copper busbar 2 is clamped and reliably fixed in one go, and the copper busbar notch 4 is accurately positioned. This effectively ensures the positional accuracy, shape consistency and processing efficiency of the multi-copper busbar notch 4. It is particularly suitable for the high-precision and mass production of the copper busbar 2 of the air-cooled magnetic pole coil of the pumped storage motor. The specific process for processing the copper busbar of the internal cold magnetic pole coil in this invention is as follows: First, machining tool kit 1: A tool holder 1, 50-100mm thick and the same length as the copper busbar 2, and more than twice the width of the copper busbar 2, is machined using a giant machine tool for milling and grinding. A groove 3, with a width more than 1.05 times the width of the copper busbar 2, is formed in the middle of the tool holder 1 along its length. One side of the groove 3 is closed, while the other side is open along the length. The depth of the groove 3 is 0.2-1mm less than the thickness of the copper busbar 2. The straightness of the groove 3 is guaranteed to be within 0.1mm / m, and the flatness of the groove 3 is 0.2mm per meter along the length. The straightness of the closed wide side of the groove 3 is 0.02mm, and its perpendicularity to the long side is 0.05mm. A row of threaded holes for fixing the pressure strip 6 is machined at a position more than 10mm away from the long side of the groove 3, with a threaded hole spacing of 200mm. Tool notches 5, identical in number, width, and position to the four copper busbar notches 4 that need to be machined on the copper busbar 2, are milled and ground on both long sides of the groove 3. The depth of each tool notch 5 is more than 5mm, and the position of each tool notch 5 is based on the unopened wide side of the groove 3, with a positional tolerance of 0.05mm. This 0.05mm positional tolerance is ensured by multiple machining operations, with measurements taken during machining. By measuring the positional tolerance and then performing compensating cutting, the positional tolerance is ultimately guaranteed, thereby avoiding the cumulative error introduced by the tool holder 1 into the giant machine tool guideway.

[0083] Then, process copper busbar 2: The wide edge of the water-sealed extruded copper busbar 2, after rough cutting, is precision machined to ensure that the perpendicularity between the wide edge and the long edge of the copper busbar 2 is within 0.05mm, and the chamfered burrs on the machined surface are removed. The machined copper busbar 2 is placed into the groove 3 of the tool holder 1, close to the unopened wide edge of the groove 3, and the long edge of the copper busbar 2 is close to the side edge of the groove 3, which is the edge closest to the bolt hole. The pressure strips 6 are assembled one by one, with one end of the pressure strip 6 engaging in the bolt hole of the tool holder 1, and the other end pressing the copper busbar 2. To protect the surface of the copper busbar 2, felt cloth 7 is adhered to the pressure strip 6. The bolt torque is kept basically consistent, with an error range of 20%. The tool holder 1 and the copper busbar 2 are placed together on a small-size high-precision milling machine for milling the notch 4 of the copper busbar. When milling each copper busbar notch 4, the tool notch 5 at the corresponding position of the tool holder 1 is used as a reference for re-alignment and machining, ensuring that the milling tool marks are less than 0.02mm. High-precision slow milling is used in one pass to ensure that the copper busbar 2 does not warp severely due to stress release after machining. The sides of the copper busbar notch 4 are uniformly chamfered to remove burrs.

[0084] After processing, the burrs on the copper busbar notches 4 are inspected, and the positional dimensions of the copper busbar notches 4 are checked. During the inspection, the copper busbar 2 is kept on the tool holder 1. This inspection process is based on the positional accuracy of each copper busbar notch 4 not exceeding 0.1mm. Since the tool notch 5 of the tool holder 1 has a precision of 0.05mm, the tool setting and alignment error can be controlled within 0.02mm. Combined with the processing error, it can be ensured that the positional accuracy of all copper busbar notches 4 on the copper busbar 2 is within 0.1mm, thus achieving high-precision processing. If there are any burrs that have not been completely removed, they are manually removed with sandpaper. After everything is completed, all pressure strips 6 are released, and the copper busbar 2 is kept in the groove 3 of the tool holder 1. The positional accuracy of 1 / 10 of the total number of copper busbar notches 4 is checked again.

Claims

1. A processing method for pumped storage air-cooled magnetic pole coil copper bars, characterized in that, Includes the following steps: S1. Machining tool kit (1): Machining a groove (3) that matches the copper busbar (2) on the tool kit (1). One end of the groove (3) is an open end, and the other end of the groove (3) is a closed end. S2. A tool notch (5) is machined along the length of the tool blank (1) to be consistent with the copper busbar notch (4). There are multiple tool notches (5). S3. Install multiple pressure strips (6) along the length of the tool fixture (1), place the copper busbar (2) into the groove (3) of the tool fixture (1), and press the copper busbar (2) tightly by the pressure strips (6); S4. Place the tool kit (1) together with the copper busbar (2) on the milling machine to mill the notch (4) of the copper busbar.

2. The method for processing copper busbars of internal cold magnetic pole coils in pumped-storage hydroelectric systems according to claim 1, characterized in that: In S1, the straightness of the groove (3) is 0.1 mm / m.

3. The method for processing copper busbars of internal cold magnetic pole coils in pumped water storage according to claim 1, characterized in that: In S1, the flatness of the groove (3) within a range of 0.2 mm per meter along its length is 0.2 mm.

4. The method for processing copper busbars of internal cold magnetic pole coils in pumped-storage hydroelectric systems according to claim 1, characterized in that: In S1, there are one or more grooves (3). When there are multiple grooves (3), any two grooves (3) are parallel to each other.

5. The method for processing copper busbars of internal cold magnetic pole coils in pumped-storage hydroelectric systems according to claim 1, characterized in that: In S2, setting tool notches (5) that are consistent with copper busbar notches (4) means that the number, width and position of tool notches (5) are the same as those of copper busbar notches (4).

6. The method for processing copper busbars of internal cold magnetic pole coils in pumped water storage according to claim 1, characterized in that: The tool notch (5) is based on the width of the unopened groove (3), with a positional tolerance of 0.05 mm.

7. The method for processing copper busbars of internal cold magnetic pole coils in pumped-storage hydroelectric systems according to claim 1, characterized in that: In S3, the copper busbar (2) is formed by water seal extrusion. After the width side is finely machined, the perpendicularity between the width side and the long side of the copper busbar (2) is 0.05mm.

8. The method for processing copper busbars of internal cold magnetic pole coils in pumped-storage hydroelectric systems according to claim 1, characterized in that: In S3, installing multiple pressure strips (6) in the length direction of the tool kit (1) means machining multiple threaded holes in the length direction of the tool kit (1), with the distance between any two adjacent threaded holes being 200mm, and the pressure strips (6) being placed on the threaded holes.

9. A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems according to claim 1, characterized in that: In S3, a felt cloth (7) is bonded to the pressure strip (6). The felt cloth (7) is located between the pressure strip (6) and the copper busbar (2). The size of the felt cloth (7) is the same as that of the pressure strip (6).

10. A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems according to claim 1, characterized in that: In S4, the milling process uses slow milling.

11. A method for processing copper busbars for internal cold magnetic pole coils in pumped-storage hydroelectric systems according to claim 1, characterized in that: In S4, the milling of the copper busbar notch (4) refers to the re-alignment and machining based on the tool notch (5), and the milling tool mark is less than 0.02mm.

12. An application of a copper busbar for an internal cold magnetic pole coil in pumped hydro storage, characterized in that: The copper busbar processing method for pumped storage air-cooled magnetic pole coils as described in claim 1 is applicable to pumped storage air-cooled magnetic pole coils.

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