Low-hot-spot large-current coil structure
By adopting a parallel-connected end current-shafting sub-coil and continuous sub-coil structure in a low-voltage large-capacity transformer, the hot spot problem caused by large current on the low-voltage side is solved, and the effect of reducing the hot spot temperature and improving the reliability of the transformer is achieved.
Patent Information
- Application Number
- CN202411671096.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-21
- Publication Date
- 2025-03-14
AI Technical Summary
In low-voltage and large capacity transformers, the low-voltage side current is large, resulting in excessive loss of the sub-coil at the end and excessive temperature, which will pull up the hot spot of the high-current coil, affecting the safety and service life of the transformer.
A high current coil structure with low heat spot is adopted, including the upper half coil, the lower half coil, the first end connection line and the tail end connection line. The upper half coil and the lower half coil both contain the end current equalization sub-coil and the continuous sub-coil. The end current equalization sub-coil and the continuous sub-coil are connected in parallel through the first and tail end connection lines to reduce the influence of the leakage magnetic field on the end coil current.
It effectively reduces the hot spot temperature of the high-current coil and improves the reliability and service life of the transformer.
Smart Images
Figure CN119626726A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of transformers, and in particular relates to a low-hot-spot high-current coil structure. Background Art
[0002] In low-voltage, large-capacity transformers, the current on the low-voltage side of the transformer is very large, even up to tens of thousands of amperes. In order to ensure the safety of the transformer, it is necessary to use large-section wires for coil winding, or connect multiple wires in parallel for coil winding. However, when the current reaches a certain level, using large-section wires will cause problems such as excessive coil additional loss and inability to process and manufacture. In order to solve this problem, the general method is to wind multiple groups of identical sub-coils on the axial direction of the core, and connect all the sub-coils in parallel to the current, so that the current in each sub-coil is reduced, reducing the difficulty of manufacturing high-current coils. The multiple groups of axially distributed sub-coils are connected in parallel, and each group of sub-coils is located at a different position of the leakage magnetic field formed by the device body. Under the action of the leakage magnetic field, the current in the sub-coil at the end is significantly higher than the current in the sub-coil at other positions, resulting in an unbalanced current distribution phenomenon in the axial direction of the iron core. When the current on the low-voltage side of the transformer is larger and the number of sub-coil groups is larger, the unbalanced current distribution phenomenon is more serious, resulting in excessive additional losses and high temperatures in the sub-coils at the end, seriously raising the hot spot of the high-current coil, causing the hot spot temperature of the coil to exceed the safety value, affecting the safety of transformer operation, and shortening the service life of the transformer. Summary of the invention
[0003] The purpose of the present invention is to provide a high-current coil structure with low hot spots, aiming to solve the problem that the current on the low-voltage side of a low-voltage and large-capacity transformer is large, the sub-coil loss at the end is too large, the temperature is too high, and the hot spots of the high-current coil are increased.
[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide a high-current coil structure with a low hot spot, including an upper half coil, a lower half coil, a head end connecting line and a tail end connecting line, the upper half coil includes an end current-sharing sub-coil and a continuous sub-coil, the end current-sharing sub-coil includes a first current-sharing upper wire cake and a first current-sharing lower wire cake, the first current-sharing upper wire cake is arranged at the uppermost end of the upper half coil, the first current-sharing lower wire cake is arranged at the lowermost end of the upper half coil, the first current-sharing upper wire cake and the first current-sharing lower wire cake are connected through a first current-sharing connecting line, the continuous sub-coil is arranged between the first current-sharing upper wire cake and the first current-sharing lower wire cake, and the lower half coil is provided with a plurality of wires. The half coil includes the end current-sharing sub-coil and the continuous sub-coil, the uppermost end of the lower half coil is provided with the first current-sharing upper wire cake, the lowermost end of the lower half coil is provided with the first current-sharing lower wire cake, the continuous sub-coil of the lower half coil is arranged between the first current-sharing upper wire cake and the first current-sharing lower wire cake, the continuous sub-coil includes a continuous upper wire cake and a continuous lower wire cake, the head end connecting line and the tail end connecting line are arranged along the height direction of the upper half coil and the lower half coil, the head end connecting line connects all the first current-sharing upper wire cakes and the continuous upper wire cake, and the tail end connecting line connects all the first current-sharing lower wire cakes and the continuous lower wire cake.
[0005] In a possible implementation, a first current sharing head is led out from the first current sharing upper line cake, and the other end of the first current sharing head is connected to the head end connecting line, and a first current sharing tail is led out from the first current sharing lower line cake, and the other end of the first current sharing tail is connected to the tail end connecting line.
[0006] In a possible implementation, a continuous head is led out from the continuous upper line cake, and the other end of the continuous head is connected to the head end connection line, and a continuous tail is led out from the continuous lower line cake, and the other end of the continuous tail is connected to the tail end connection line.
[0007] In a possible implementation, the continuous sub-coil further includes a continuous middle coil, and the continuous middle coil is arranged between the continuous upper coil and the continuous lower coil.
[0008] In a possible implementation, the first current sharing connection line is located on the inner side / outer side of the first current sharing upper line cake.
[0009] In a possible implementation, the upper half coil further includes a middle current balancing sub-coil, and the middle current balancing sub-coil is arranged between the first current balancing upper coil and the first current balancing lower coil.
[0010] In a possible implementation, the middle current sharing sub-coil includes a second current sharing upper coil and a second current sharing lower coil, and the second current sharing upper coil and the second current sharing lower coil are connected via a second current sharing connection line.
[0011] In a possible implementation manner, the second current sharing upper coil and the second current sharing lower coil of the same group of the middle current sharing sub-coils are not adjacent to each other.
[0012] In a possible implementation, the plurality of groups of middle current-balancing sub-coils are arranged sequentially from top to bottom.
[0013] In a possible implementation, a plurality of groups of the middle current-sharing sub-coils are nested.
[0014] The beneficial effects of a low hot spot high current coil structure provided by the present invention are: Compared with the prior art, an upper coil, a lower coil, a head end connecting line and a tail end connecting line are provided, the upper coil is arranged above the lower coil, the lower coil has a similar structure to the upper coil, the head end connecting line and the tail end connecting line are both vertically arranged along the height direction of the upper coil and the lower coil, the upper coil includes an end current-equalizing sub-coil and a continuous sub-coil, the end current-equalizing sub-coil includes a first current-equalizing upper wire cake and a first current-equalizing lower wire cake, the first current-equalizing upper wire cake and the first current-equalizing lower wire cake are connected through a first current-equalizing connecting line, the first current-equalizing upper wire cake and the first current-equalizing lower wire cake are respectively arranged at the upper and lower ends of the upper coil, the continuous sub-coil is arranged between the first current-equalizing upper wire cake and the first current-equalizing lower wire cake, similarly, the lower coil includes an end current-equalizing sub-coil and a continuous sub-coil, the first current-equalizing upper wire cake and the first current-equalizing lower wire cake The connection is made through the first current-sharing connecting line. The first current-sharing upper wire cake and the first current-sharing lower wire cake are respectively arranged at the upper and lower ends of the lower half coil. The continuous sub-coil is arranged between the first current-sharing upper wire cake and the first current-sharing lower wire cake. The continuous sub-coil includes a continuous upper wire cake and a continuous lower wire cake. The continuous upper wire cake and the first current-sharing upper wire cake are both connected to the head end connecting line. The continuous lower wire cake and the first current-sharing lower wire cake are both connected to the tail end connecting line. The end current-sharing sub-coil realizes the series connection between the wire cake at the end and the wire cake in the middle of the entire large current coil, reduces the influence of the leakage magnetic field of the transformer body on the end coil current, thereby reducing the unbalanced current of the coil at the upper end of the upper half coil and the lower end of the lower half coil, thereby reducing its loss and temperature, reducing the hot spot of the entire large current coil, improving the reliability of the transformer, and extending the life of the transformer. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0016] Figure 1 A schematic structural diagram of a low hot spot high current coil structure provided by an embodiment of the present invention; Figure 2 A schematic diagram of the structure of the end current equalizer coil used in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the end continuous sub-coil used in an embodiment of the present invention.
[0017] In the figure: 100, upper half coil; 200, lower half coil; 300, head end connecting line; 400, tail end connecting line; 110, end current equalizing sub-coil; 111, first current equalizing upper line cake; 112, first current equalizing head; 113, first current equalizing connecting line; 114, first current equalizing lower line cake; 115, first current equalizing tail; 120, continuous sub-coil; 122, continuous upper line cake; 123, continuous head; 124, continuous lower line cake; 125, continuous tail. DETAILED DESCRIPTION
[0018] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0019] Please refer to Figures 1 to 3A specific embodiment of a low hot spot high current coil structure provided by the present invention is now described, including an upper half coil 100, a lower half coil 200, a head end connecting line 300 and a tail end connecting line 400, the upper half coil 100 includes an end current balancing sub-coil 110 and a continuous sub-coil 120, the end current balancing sub-coil 110 includes a first current balancing upper wire cake 111 and a first current balancing lower wire cake 114, the first current balancing upper wire cake 111 is arranged at the uppermost end of the upper half coil 100, the first current balancing lower wire cake 114 is arranged at the lowermost end of the upper half coil 100, the first current balancing upper wire cake 111 and the first current balancing lower wire cake 114 are connected through a first current balancing connecting line 113, and the continuous sub-coil 120 is arranged between the first current balancing upper wire cake 111 and the first current balancing lower wire cake 114 The lower half coil 200 includes an end current-equalizing sub-coil 110 and a continuous sub-coil 120. The uppermost end of the lower half coil 200 is provided with a first current-equalizing upper wire cake 111, and the lowermost end of the lower half coil 200 is provided with a first current-equalizing lower wire cake 114. The continuous sub-coil 120 of the lower half coil 200 is arranged between the first current-equalizing upper wire cake 111 and the first current-equalizing lower wire cake 114. The continuous sub-coil 120 includes a continuous upper wire cake 122 and a continuous lower wire cake 124. The head end connecting line 300 and the tail end connecting line 400 are arranged along the height direction of the upper half coil 100 and the lower half coil 200. The head end connecting line 300 connects all the first current-equalizing upper wire cakes 111 and the continuous upper wire cake 122, and the tail end connecting line 400 connects all the first current-equalizing lower wire cakes 114 and the continuous lower wire cake 124.
[0020] The present invention provides a low hot spot high current coil structure. Compared with the prior art, the present invention is provided with an upper half coil 100, a lower half coil 200, a head end connecting line 300 and a tail end connecting line 400. The upper half coil 100 is arranged above the lower half coil 200. The lower half coil 200 has a similar structure to the upper half coil 100. The head end connecting line 300 and the tail end connecting line 400 are both arranged vertically along the height direction of the upper half coil 100 and the lower half coil 200. The upper half coil 100 includes an end current equalizing sub-coil 110 and a continuous sub-coil 120, the end current-sharing sub-coil 110 includes a first current-sharing upper wire cake 111 and a first current-sharing lower wire cake 114, the first current-sharing upper wire cake 111 and the first current-sharing lower wire cake 114 are connected by a first current-sharing connecting line 113, the first current-sharing upper wire cake 111 and the first current-sharing lower wire cake 114 are respectively arranged at the upper and lower ends of the upper half coil 100, and the continuous sub-coil 120 is arranged between the first current-sharing upper wire cake 111 and the first current-sharing lower wire cake 114. Similarly, the lower half coil 200 includes the end current-sharing sub-coil 110 and the continuous sub-coil 120. The continuous sub-coil 120, the first current-sharing upper wire cake 111 and the first current-sharing lower wire cake 114 are connected through the first current-sharing connecting line 113, the first current-sharing upper wire cake 111 and the first current-sharing lower wire cake 114 are respectively arranged at the upper and lower ends of the lower half coil 200, the continuous sub-coil 120 is arranged between the first current-sharing upper wire cake 111 and the first current-sharing lower wire cake 114, the continuous sub-coil 120 includes a continuous upper wire cake 122 and a continuous lower wire cake 124, the continuous upper wire cake 122 and the first current-sharing upper wire cake 111 are connected to the head end connecting line 3 00 connection, the continuous lower wire coil 124 and the first current-sharing lower wire coil 114 are all connected to the tail connecting line 400, and the end current-sharing sub-coil 110 realizes the series connection between the wire coil at the end and the wire coil in the middle of the entire high-current coil, reducing the influence of the leakage magnetic field of the transformer body on the end coil current, thereby reducing the unbalanced current of the coil at the upper end of the upper half coil 100 and the lower end of the lower half coil 200, thereby reducing its loss and temperature, reducing the hot spots of the entire high-current coil, improving the reliability of the transformer, and extending the life of the transformer.
[0021] For details, please refer to Figures 1 to 3, the upper coil 100 and the lower coil 200 are arranged from top to bottom, and the compositions of the upper coil 100 and the lower coil 200 are similar, both of which include an end current-equalizing sub-coil 110 and a continuous sub-coil 120. The total number of coils of the upper coil 100 and the lower coil 200 is the same. The upper coil 100 includes a group of end current-equalizing sub-coils 110, and the first current-equalizing upper coil 111 and the first current-equalizing lower coil 114 of a group of end current-equalizing sub-coils 110 are respectively arranged at the upper and lower ends of the upper coil 100, and the first current-equalizing connecting line 113 connects the first current-equalizing upper coil 111 and the first current-equalizing lower coil 114. The lower coil 200 includes a group of end current-equalizing sub-coils 110, and the first current-equalizing upper coil 111 and the first current-equalizing lower coil 114 of a group of end current-equalizing sub-coils 110 are respectively arranged at the upper and lower ends of the lower coil 200, and the first current-equalizing connecting line 113 connects the first current-equalizing upper coil 111 and the first current-equalizing lower coil 114. The continuous sub-coil 120 is arranged in the middle of the upper half coil 100 and the lower half coil 200. The continuous sub-coil 120 includes a continuous upper wire cake 122 and a continuous lower wire cake 124. The continuous upper wire cake 122 and the continuous lower wire cake 124 are connected in series. The continuous sub-coil 120 is arranged from top to bottom. The head end connecting line 300 connects all the first upper current equalizing wire cakes 111 and the continuous upper wire cake 122 of the upper half coil 100 and the lower half coil 200, and the tail end connecting line 400 connects all the first lower current equalizing wire cakes 114 and the continuous lower wire cake 124 of the upper half coil 100 and the lower half coil 200. The more the number of continuous sub-coils 120 between the first upper current equalizing wire cake 111 and the first lower current equalizing wire cake 114 of a group of end current equalizing sub-coils 110, the greater the current reduction ratio in the end current equalizing sub-coil 110, and the better the effect of reducing the hot spots of the large current coil.
[0022] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 A first current sharing head 112 is led out from the first current sharing upper line cake 111, and the other end of the first current sharing head 112 is connected to the head end connecting line 300, and a first current sharing tail head 115 is led out from the first current sharing lower line cake 114, and the other end of the first current sharing tail head 115 is connected to the tail end connecting line 400.
[0023] For details, please refer to Figures 1 to 3 The first current equalizing upper wire cake 111 leads to the first current equalizing head 112 outward, and the first current equalizing lower wire cake 114 leads to the first current equalizing tail 115 outward. The ends of the two groups of first current equalizing heads 112 away from the first current equalizing upper wire cake 111 are both arranged on the head end connecting line 300, and the ends of the two groups of first current equalizing tail heads 115 away from the first current equalizing lower wire cake 114 are both arranged on the tail end connecting line 400, thereby realizing the parallel connection of the two groups of end current equalizing sub-coils 110.
[0024] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 A continuous head 123 is led out from the continuous upper line cake 122, and the other end of the continuous head 123 is connected to the head end connection line 300, and a continuous tail head 125 is led out from the continuous lower line cake 124, and the other end of the continuous tail head 125 is connected to the tail end connection line 400.
[0025] For details, please refer to Figures 1 to 3 The continuous upper wire cake 122 leads outwardly to a continuous head 123, and the continuous lower wire cake 124 leads outwardly to a continuous tail 125, and the ends of multiple groups of continuous head 123 away from the continuous upper wire cake 122 are all arranged on the head end connecting line 300, and the ends of multiple groups of continuous tail heads 125 away from the continuous lower wire cake 124 are all arranged on the tail end connecting line 400, thereby realizing the parallel connection of multiple groups of continuous sub-coils 120.
[0026] For further information, please refer to Figures 1 to 3 The head end connecting wire 300 and the tail end connecting wire 400 realize the parallel connection of all end current-sharing sub-coils 110 and the continuous sub-coil 120. The head end connecting wire 300 and the tail end connecting wire 400 are led out as the head end and the tail end of the large current coil structure.
[0027] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 The continuous sub-coil 120 further includes a continuous middle coil, which is disposed between the continuous upper coil 122 and the continuous lower coil 124 .
[0028] For details, please refer to Figures 1 to 3 The continuous sub-coil 120 further includes a continuous middle coil, which is disposed in the middle of the continuous sub-coil 120 , and the continuous middle coil may be provided with one or more groups of coils.
[0029] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 The first current sharing connection line 113 is located on the inner side / outer side of the first current sharing upper line cake 111 .
[0030] For details, please refer to Figures 1 to 3 The first current sharing connection line 113 may be located on the inner side of the end current sharing sub-coil 110 and the continuous sub-coil 120 , or may be located on the outer side of the end current sharing sub-coil 110 and the continuous sub-coil 120 .
[0031] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 The upper half coil 100 also includes a middle current balancing sub-coil, which is arranged between the first current balancing upper coil 111 and the first current balancing lower coil 114.
[0032] For details, please refer to Figures 1 to 3 The upper coil 100 and the lower coil 200 both include a middle current-balancing sub-coil, and the middle current-balancing sub-coil is distributed in the middle of the upper coil 100 / the lower coil 200, so as to further reduce the unbalanced current.
[0033] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 The middle current-sharing sub-coil includes a second current-sharing upper wire cake and a second current-sharing lower wire cake, and the second current-sharing upper wire cake and the second current-sharing lower wire cake are connected by a second current-sharing connecting line.
[0034] For details, please refer to Figures 1 to 3 The middle current-sharing sub-coil includes a second current-sharing upper wire cake and a second current-sharing lower wire cake. The second current-sharing upper wire cake is arranged above the second current-sharing lower wire cake. The second current-sharing connecting line connects the second current-sharing upper wire cake and the second current-sharing lower wire cake.
[0035] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 The second current-sharing upper coil and the second current-sharing lower coil of the same group of middle current-sharing sub-coils are not adjacent.
[0036] For details, please refer to Figures 1 to 3 A coil of a continuous sub-coil 120 is arranged between the second upper current-equalizing coil and the second lower current-equalizing coil of the same group of middle current-equalizing sub-coils. Coils from other middle current-equalizing sub-coils may also be arranged. The coil of the middle current-equalizing sub-coil will not be arranged between coils of the same group of continuous sub-coils 120.
[0037] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 , multiple groups of middle current-balancing coils are arranged sequentially from top to bottom.
[0038] For details, please refer to Figures 1 to 3 In the upper half coil or / and the lower half coil, multiple groups of middle current balancing sub-coils are arranged, and a continuous sub-coil 120 is arranged between the second current balancing upper wire cake and the second current balancing lower wire cake of each group of middle current balancing sub-coils, and multiple groups of middle current balancing sub-coils are arranged in sequence.
[0039] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 , multiple groups of middle current-balancing coils are nested.
[0040] For details, please refer to Figures 1 to 3In the upper half coil or / and the lower half coil, multiple groups of middle current balancing sub-coils are arranged, and a continuous sub-coil 120 is arranged between the second current balancing upper wire cake and the second current balancing lower wire cake of each group of middle current balancing sub-coils. Multiple groups of middle current balancing sub-coils can be nested, that is, between the second current balancing upper wire cake and the second current balancing lower wire cake of one group of middle current balancing sub-coils, there are one or two groups of wire cakes in other groups of middle current balancing sub-coils.
[0041] As a specific implementation of a low hot spot high current coil structure provided by the present invention, please refer to Figures 1 to 3 All the coils of the low hot spot large current coil structure are wound by wires of the same cross-section. The first current-sharing connecting wire 113 and the second current-sharing connecting wire can be made of wires of the same cross-section, or can be made of conductive materials such as soft copper strips that take up little space and are easy to make according to actual needs when space is limited or it is inconvenient to make.
[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A low hot spot high current coil structure, characterized in that: The invention comprises an upper half coil, a lower half coil, a head end connecting line and a tail end connecting line, wherein the upper half coil comprises an end current-sharing sub-coil and a continuous sub-coil, wherein the end current-sharing sub-coil comprises a first current-sharing upper wire cake and a first current-sharing lower wire cake, wherein the first current-sharing upper wire cake is arranged at the uppermost end of the upper half coil, and the first current-sharing lower wire cake is arranged at the lowermost end of the upper half coil, wherein the first current-sharing upper wire cake and the first current-sharing lower wire cake are connected through a first current-sharing connecting line, wherein the continuous sub-coil is arranged between the first current-sharing upper wire cake and the first current-sharing lower wire cake, wherein the lower half coil comprises the end current-sharing sub-coil and the continuous sub-coil, wherein the end current-sharing sub-coil comprises a first current-sharing upper wire cake and a first current-sharing lower wire cake ... end current-sharing A continuous sub-coil, the uppermost end of the lower half coil is provided with the first current-sharing upper wire cake, the lowermost end of the lower half coil is provided with the first current-sharing lower wire cake, the continuous sub-coil of the lower half coil is arranged between the first current-sharing upper wire cake and the first current-sharing lower wire cake, the continuous sub-coil includes a continuous upper wire cake and a continuous lower wire cake, the head end connecting line and the tail end connecting line are arranged along the height direction of the upper half coil and the lower half coil, the head end connecting line connects all the first current-sharing upper wire cakes and the continuous upper wire cake, and the tail end connecting line connects all the first current-sharing lower wire cakes and the continuous lower wire cake.
2. A low hot spot high current coil structure as claimed in claim 1, characterized in that: A first current sharing head is led out from the first current sharing upper line cake, and the other end of the first current sharing head is connected to the head end connecting line. A first current sharing tail is led out from the first current sharing lower line cake, and the other end of the first current sharing tail is connected to the tail end connecting line.
3. A low hot spot high current coil structure as claimed in claim 1, characterized in that: A continuous head is led out from the continuous upper line cake, and the other end of the continuous head is connected to the head end connecting line. A continuous tail is led out from the continuous lower line cake, and the other end of the continuous tail is connected to the tail end connecting line.
4. A low hot spot high current coil structure as claimed in claim 1, characterized in that: The continuous sub-coil further includes a continuous middle coil, and the continuous middle coil is arranged between the continuous upper coil and the continuous lower coil.
5. A low hot spot high current coil structure as claimed in claim 1, characterized in that: The first current sharing connection line is located on the inner side / outer side of the first current sharing upper line cake.
6. A low hot spot high current coil structure as claimed in claim 1, characterized in that: The upper half coil also includes a middle current balancing sub-coil, and the middle current balancing sub-coil is arranged between the first current balancing upper coil and the first current balancing lower coil.
7. A low hot spot high current coil structure as claimed in claim 6, characterized in that: The middle current-sharing sub-coil includes a second current-sharing upper coil and a second current-sharing lower coil, and the second current-sharing upper coil and the second current-sharing lower coil are connected via a second current-sharing connecting line.
8. A low hot spot high current coil structure as claimed in claim 7, characterized in that: The second current-sharing upper coil and the second current-sharing lower coil of the same group of the middle current-sharing sub-coils are not adjacent to each other.
9. A low hot spot high current coil structure as claimed in claim 8, characterized in that: The plurality of groups of middle current-balancing coils are arranged in sequence from top to bottom.
10. A low hot spot high current coil structure as claimed in claim 8, characterized in that: A plurality of groups of the middle current-balancing coils are nested.