Rotor conducting bar, rotor assembly and generator

Abstract

The invention provides a rotor conducting bar, a rotor assembly and a generator, the rotor conducting bar comprises a first conducting section and a second conducting section, and at least part of the first conducting section is used for being arranged on a rotor core of the rotor assembly; the second conductive section is in butt joint with the first conductive section, one end, far away from the first conductive section, of the second conductive section exceeds the rotor core in the axial direction of the rotor core, and the heat conductivity coefficient and / or conductivity of the material of the second conductive section is greater than that of the material of the first conductive section. The rotor conducting bar is made of a mixed material, the first conducting section forms the part, located in the iron core groove, of the rotor conducting bar, and the second conducting section forms the end part of the rotor conducting bar, so that the heat conductivity coefficient and / or the electric conductivity of the material of the end part of the rotor conducting bar are / is larger than that of the part, located in the iron core groove, of the rotor conducting bar; therefore, the temperature of the whole rotor conducting bar is uniform, and the temperature of the whole rotor winding formed by the rotor conducting bar made of the mixed material is also uniform.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of power generation equipment, and particularly to a rotor conductive bar, a rotor assembly and a generator. Background Art

[0002] With the advent of the era of wind power parity, in order to reduce the cost per kilowatt-hour of the unit, wind turbines are developing towards high power. Doubly-fed generators are mainly used in wind turbines. The rotor assembly of a doubly-fed generator includes a rotor core and a rotor winding. The rotor core is provided with core slots. The main material of the rotor winding is copper. The middle part of the rotor winding is embedded in the core slots of the rotor core, and both ends of the rotor winding are located outside the core slots of the rotor core. Generally, the end structure of the rotor winding is compact, and the cooling effect is poor, so that the temperature rise at the end of the rotor winding is more than 20K higher than that of the part of the rotor winding located in the core slot. In order to meet the overall temperature rise requirements of the doubly-fed generator, the overall current density and thermal load of the rotor assembly are relatively small during the design of the generator, which leads to design redundancy of the rotor winding in the core slot, thus increasing the overall cost of the doubly-fed generator. Summary of the Invention

[0003] The purpose of the embodiments of the present invention is to provide a rotor conductive bar, a rotor assembly and a generator, aiming to achieve uniform temperature of the entire rotor winding of the doubly-fed generator.

[0004] To solve the above technical problems, an embodiment of the present invention provides a rotor conductive bar for a rotor assembly, and the rotor conductive bar includes:

[0005] A first conductive section, at least part of which is used to be arranged on the rotor core of the rotor assembly;

[0006] A second conductive section, one end of which is butted against one end of the first conductive section, and the end of the second conductive section far from the first conductive section extends beyond the rotor core in the axial direction of the rotor core;

[0007] Wherein, the thermal conductivity of the material of the second conductive section is greater than that of the material of the first conductive section; and / or, the conductivity of the material of the second conductive section is greater than that of the material of the first conductive section.

[0008] In some embodiments, the density of the first conductive section is less than that of the second conductive section.

[0009] In some embodiments, the density of the material of the first conductive section is less than that of the material of the second conductive section.

[0010] In some embodiments, the material of the first conductive section is aluminum, and the material of the second conductive section is copper.

[0011] In some embodiments, there are two second conductive segments, and the two second conductive segments are respectively butted against both ends of the first conductive segment.

[0012] To achieve the above object, the present invention further provides a rotor assembly, including:

[0013] A rotating shaft;

[0014] A rotor core sleeved on the rotating shaft;

[0015] A rotor busbar, which is the above-mentioned rotor busbar. At least a part of the first conductive segment of the rotor busbar is disposed on the rotor core, and one end of the second conductive segment of the rotor busbar far from the first conductive segment extends beyond the rotor core in the axial direction of the rotor core.

[0016] In some embodiments, a core slot extending along the axial direction of the rotor core is formed on the outer peripheral side surface of the rotor core, and the part of the rotor busbar disposed on the rotor core is embedded in the core slot.

[0017] In some embodiments, one end of the second conductive segment close to the first conductive segment extends into the core slot.

[0018] In some embodiments, a radial ventilation slot extending along the circumferential direction of the rotor core is formed on the outer peripheral side surface of the rotor core. The radial ventilation slot communicates with the core slot, and the butt joint of the second conductive segment and the first conductive segment is located at the communication position of the core slot and the radial ventilation slot.

[0019] To achieve the above object, the present invention further provides a generator, including the above-mentioned rotor assembly.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The rotor conducting bar of the present invention is a rotor conducting bar made of a hybrid material. The rotor conducting bar includes a first conducting segment made of a material with a lower thermal conductivity and / or electrical conductivity, and a second conducting segment made of a material with a higher thermal conductivity and / or electrical conductivity. The first conducting segment forms the part of the rotor conducting bar located in the core slot, and the second conducting segment forms the end of the rotor conducting bar, such that the thermal conductivity and / or electrical conductivity of the material at the end of the rotor conducting bar is greater than that of the material of the part of the rotor conducting bar located in the core slot. This allows the heat dissipation capacity of the end of the rotor conducting bar to be better than that of the part of the rotor conducting bar located in the core slot, and also allows the losses generated at the end of the rotor conducting bar to be less than those of the part of the rotor conducting bar located in the core slot, thereby compensating for the poor heat dissipation at the end caused by the rotor end structure, achieving uniform temperature throughout the rotor conducting bar. Moreover, the entire rotor winding composed of such a rotor conducting bar made of a hybrid material can also have a uniform temperature, meeting the overall temperature rise requirements of the doubly-fed generator. Brief Description of the Drawings

[0022] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplary illustrations do not limit the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the drawings in the figures do not constitute a scale limitation.

[0023] Figure 1 It is a schematic structural diagram of the rotor conducting bar in an embodiment of the present invention;

[0024] Figure 2 It is a schematic structural diagram of the rotor assembly in an embodiment of the present invention.

[0025] Description of the reference numerals in the drawings of the present invention:

[0026] Rotor assembly 100, rotor conducting bar 1, first conducting segment 11, second conducting segment 12, left second conducting segment 12a, right second conducting segment 12b, docking location 13, left docking location 13a, right docking location 13b, rotor core 2, core slot 21, radial ventilation slot 22, rotor laminations 23, first rotor lamination 23a, second rotor lamination 23b, third rotor lamination 23c, fourth rotor lamination 23d, rotating shaft 3.

[0027] The realization, functional features, and advantages of the object of the present invention will be further described in conjunction with the embodiments with reference to the drawings. Detailed Embodiments

[0028] As can be seen from the background art, it is currently necessary to provide a rotor conducting bar, a rotor assembly, and a generator that can achieve uniform temperature throughout the rotor winding.

[0029] The rotor current-carrying bar of the present invention is a rotor current-carrying bar made of a hybrid material. The rotor current-carrying bar includes a first current-carrying segment made of a material with a lower thermal conductivity and / or electrical conductivity, and a second current-carrying segment made of a material with a higher thermal conductivity and / or electrical conductivity. The first current-carrying segment forms the part of the rotor current-carrying bar located in the core slot, and the second current-carrying segment forms the end of the rotor current-carrying bar, so that the thermal conductivity and / or electrical conductivity of the material at the end of the rotor current-carrying bar is greater than that of the material of the part of the rotor current-carrying bar located in the core slot. This can make the heat dissipation capacity of the end of the rotor current-carrying bar better than that of the part of the rotor current-carrying bar located in the core slot, and also make the loss generated at the end of the rotor current-carrying bar less than that of the part of the rotor current-carrying bar located in the core slot, thereby compensating for the poor heat dissipation at the end caused by the rotor end structure, achieving uniform temperature of the entire rotor current-carrying bar, and the entire rotor winding composed of such a hybrid material rotor current-carrying bar can also have a uniform temperature, meeting the overall temperature rise requirements of the doubly-fed generator.

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0031] It should be noted that if there are directional indications (such as up, down, left, right, front, back,...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0032] In addition, if there are descriptions such as "first" and "second" involved in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] The present invention provides a rotor current-carrying bar, which can be used for the rotor assembly of a doubly-fed generator. Figure 1 A preferred embodiment of the rotor current-carrying bar provided by the present invention is shown. Figure 2 A preferred embodiment of the rotor assembly provided by the present invention is shown.

[0034] Please refer to Figure 1 and Figure 2 , the rotor conducting bar 1 is used for the rotor assembly 100. The rotor conducting bar 1 includes a first conducting section 11 and a second conducting section 12. At least part of the first conducting section 11 is used to be arranged on the rotor core 2 of the rotor assembly 100; One end of the second conducting section 12 is butted against one end of the first conducting section 11, and the end of the second conducting section 12 far from the first conducting section 11 extends beyond the rotor core 2 in the axial direction of the rotor core 2; Wherein, the thermal conductivity of the material of the second conducting section 12 is greater than that of the material of the first conducting section 11; And / or, the conductivity of the material of the second conducting section 12 is greater than that of the material of the first conducting section 11.

[0035] Specifically, the rotor assembly 100 includes a rotor core 2 and a rotor winding. The rotor core 2 is usually arranged in a cylindrical shape. The rotor winding is wound around the rotor core 2, and the rotor winding is formed by winding a plurality of rotor conducting bars 1. The plurality of rotor conducting bars 1 are arranged along the circumferential direction of the rotor core 2 to form the rotor winding.

[0036] The middle part of the rotor conducting bar 1 is arranged on the rotor core 2. Usually, a core slot 21 is formed on the outer peripheral side surface of the rotor core 2. The part of the rotor conducting bar 1 arranged on the rotor core 2 (i.e., the middle part of the rotor conducting bar 1) is embedded in the core slot 21. In this way, the middle parts of the plurality of rotor conducting bars 1 form the part of the rotor winding located in the core slot 21. Hereinafter, an example in which the rotor core 2 is provided with a core slot 21 for accommodating the rotor conducting bar 1 will be introduced.

[0037] The dimension of the rotor conducting bar 1 in the axial direction of the rotor core 2 is greater than the dimension of the rotor core 2 in the axial direction of the rotor core 2, so that both ends of the rotor conducting bar 1 extend beyond the rotor core 2 in the axial direction of the rotor core 2. In this way, both ends of the plurality of rotor conducting bars 1 in the axial direction of the rotor core 2 form two ends of the rotor winding.

[0038] The rotor conducting bar 1 is made of materials with different thermal conductivities and / or conductivities to form a rotor conducting bar 1 of a mixed material. The rotor conducting bar 1 includes a first conducting section 11 and a second conducting section 12. The first conducting section 11 and the second conducting section 12 are arranged along the extending direction of the rotor conducting bar 1. The two ends of the first conducting section 11 and the second conducting section 12 close to each other are butted, so as to splice into the rotor conducting bar 1. The first conducting section 11 is made of a first conducting material, and the second conducting section 12 is made of a second conducting material. And the thermal conductivity and / or conductivity of the second conducting material is greater than the thermal conductivity and / or conductivity of the first conducting material. In this way, the thermal performance and / or conductivity performance of the second conducting section 12 is better than that of the first conducting section 11.

[0039] Optionally, in this embodiment, the thermal conductivity of the material of the second conductive segment 12 is greater than that of the material of the first conductive segment 11, and the conductivity of the material of the second conductive segment 12 is greater than that of the material of the first conductive segment 11.

[0040] When the rotor conductive bar 1 is installed on the rotor core 2, at least a part of the first conductive segment 11 is embedded in the core slot 21, so that the part of the first conductive segment 11 located in the core slot 21 forms the part of the rotor conductive bar 1 located in the core slot 21. And one end of the second conductive segment 12 far from the first conductive segment 11 extends beyond the rotor core 2 in the axial direction of the rotor core 2, so that the part of the second conductive segment 12 extending beyond the rotor core 2 forms an end of the rotor conductive bar 1. Thus, the thermal conductivity of the material of the end of the rotor conductive bar 1 is greater than that of the material of the part of the rotor conductive bar 1 located in the core slot 21, and the conductivity of the material of the end of the rotor conductive bar 1 is greater than that of the material of the part of the rotor conductive bar 1 located in the core slot 21. And the fact that the thermal conductivity of the material of the end of the rotor conductive bar 1 is greater than that of the material of the part of the rotor conductive bar 1 located in the core slot 21 can make the thermal performance of the end of the rotor conductive bar 1 better than that of the part of the rotor conductive bar 1 located in the core slot 21; and the fact that the conductivity of the material of the end of the rotor conductive bar 1 is greater than that of the material of the part of the rotor conductive bar 1 located in the core slot 21 can make the conductive performance of the end of the rotor conductive bar 1 better than that of the part of the rotor conductive bar 1 located in the core slot 21, that is, the resistance of the end of the rotor conductive bar 1 is less than that of the part of the rotor conductive bar 1 located in the core slot 21. Thus, under the same current, the loss generated at the end of the rotor conductive bar 1 is less than that generated by the part of the rotor conductive bar 1 located in the core slot 21. Thus, by superimposing the advantages brought by the different thermal conductivities and conductivities, the poor end heat dissipation caused by the rotor end structure can be compensated, and the temperature uniformity of the whole rotor conductive bar 1 can be realized. When using the rotor conductive bar 1 made of such a hybrid material to form the rotor winding, since the temperature of the whole of the multiple rotor conductive bars 1 forming the rotor winding is uniform, the temperature of the whole rotor winding can also be uniform, so as to meet the temperature rise requirements of the whole doubly-fed generator.

[0041] The rotor conducting bar 1 of the present invention is a rotor conducting bar 1 made of a hybrid material. The rotor conducting bar 1 includes a first conducting segment 11 made of a material with a lower thermal conductivity and / or electrical conductivity, and a second conducting segment 12 made of a material with a higher thermal conductivity and / or electrical conductivity. The first conducting segment 11 forms the part of the rotor conducting bar 1 located within the core slot 21, and the second conducting segment 12 forms the end portion of the rotor conducting bar 1, such that the thermal conductivity and / or electrical conductivity of the material of the end portion of the rotor conducting bar 1 are both greater than those of the material of the part of the rotor conducting bar 1 located within the core slot 21. This allows the heat dissipation capacity of the end portion of the rotor conducting bar 1 to be better than that of the part of the rotor conducting bar 1 located within the core slot 21, and also allows the losses generated at the end portion of the rotor conducting bar 1 to be less than those of the part of the rotor conducting bar 1 located within the core slot 21, thereby compensating for the poor heat dissipation at the end caused by the rotor end structure, achieving uniform temperature throughout the rotor conducting bar 1. Moreover, the entire rotor winding composed of such a rotor conducting bar 1 made of a hybrid material can also have a uniform temperature, meeting the overall temperature rise requirements of the doubly-fed generator.

[0042] The embodiments of the present invention will be described in more detail below with reference to the accompanying drawings.

[0043] The rotor conducting bar 1 includes a first conducting segment 11 and a second conducting segment 12. The rotor conducting bar 1 may include only one first conducting segment 11 and one second conducting segment 12. In this case, the end of the first conducting segment 11 remote from the second conducting segment 12 extends axially beyond the rotor core 2 in the axial direction of the rotor core 2, such that the portions of the first conducting segment 11 and the second conducting segment 12 that extend beyond the rotor core 2 respectively form the two end portions of the rotor conducting bar 1. The rotor conducting bar 1 may also include two second conducting segments 12, and the two second conducting segments 12 are respectively butt-jointed to the two ends of the first conducting segment 11. In this case, the two ends of the two second conducting segments 12 remote from the first conducting segment 11 respectively form the two end portions of the rotor conducting bar 1. The rotor conducting bar 1 may further include a third conducting segment, one end of the third conducting segment is butt-jointed to the end of the first conducting segment 11 remote from the second conducting segment 12. In this case, the end of the second conducting segment 12 remote from the first conducting segment 11 and the end of the third conducting segment remote from the first conducting segment 11 respectively form the two end portions of the rotor conducting bar 1, wherein the third conducting segment is made of a third conducting material, and the thermal conductivity and / or electrical conductivity of the third conducting material are different from those of the first conducting material and the second conducting material. For example, the thermal conductivity and / or electrical conductivity of the third conducting material are greater than those of the first conducting material, and the thermal conductivity and / or electrical conductivity of the third conducting material are greater than or less than those of the second conducting material.

[0044] Optionally, please refer to Figure 1 and Figure 2, in this embodiment, there are two second conductive segments 12, and the two second conductive segments 12 are respectively butted against both ends of the first conductive segment 11.

[0045] Specifically, the first conductive segment 11 is generally arranged to extend along the axial direction of the rotor core 2. The rotor conductive bar 1 includes two second conductive segments 12, and the two second conductive segments 12 are respectively located on both sides of the first conductive segment 11 in the axial direction of the rotor core 2. Both ends of the first conductive segment 11 are respectively butted against the two second conductive segments 12. The two ends of the two second conductive segments 12 away from the first conductive segment 11 respectively extend beyond the rotor core 2 in opposite directions in the axial direction of the rotor core 2, so that the two ends of the two second conductive segments 12 away from the first conductive segment 11 respectively form the two ends of the rotor conductive bar 1. In this way, by respectively forming the two ends of the rotor conductive bar 1 with the two second conductive segments 12, it can be realized that both ends of the rotor conductive bar 1 can have heat conduction performance and electrical conduction performance, which is beneficial to ensuring the overall temperature uniformity of the rotor conductive bar 1.

[0046] Next, an example in which there are two second conductive segments 12 will be introduced, and the axial direction of the rotor core 2 is defined as the left - right direction. The first conductive segment 11 is arranged to extend along the left - right direction. The two second conductive segments 12 are respectively located on the left and right sides of the first conductive segment 11. One of the two second conductive segments 12 located on the left side of the first conductive segment 11 is the left - hand second conductive segment 12a, and the one located on the right side of the first conductive segment 11 is the right - hand second conductive segment 12b. The right end of the left - hand second conductive segment 12a is butted against the left end of the first conductive segment 11, and the left end of the left - hand second conductive segment 12a extends beyond the rotor core 2 to the left. In this way, the left end of the left - hand second conductive segment 12a forms the left end of the rotor conductive bar 1. Similarly, the left end of the right - hand second conductive segment 12b is butted against the right end of the first conductive segment 11, and the right end of the right - hand second conductive segment 12b extends beyond the rotor core 2 to the right. In this way, the right end of the right - hand second conductive segment 12b forms the right end of the rotor conductive bar 1.

[0047] Optionally, in this embodiment, the density of the first conductive segment 11 is less than the density of the second conductive segment 12.

[0048] Specifically, since the density of the first conductive segment 11 is less than the density of the second conductive segment 12, for the same volume of the first conductive segment 11 and the second conductive segment 12, the weight of the first conductive segment 11 is less than the weight of the second conductive segment 12. In this way, the weight of the rotor conductive bar 1 can be reduced, so that the rotor deflection and bearing load of the generator can also be correspondingly reduced, thereby improving the reliability of the generator.

[0049] There are various specific ways to achieve that the density of the first conductive segment 11 is less than that of the second conductive segment 12. For example, the first conductive segment 11 can be provided with weight-reducing cavities or holes and other weight-reducing structures, so that the density of the first conductive segment 11 is less than that of the second conductive segment 12. In this way, when the volume of the first conductive segment 11 remains unchanged, by setting weight-reducing structures on the first conductive segment 11, the density of the first conductive segment 11 can be reduced, thereby achieving that the density of the first conductive segment 11 is less than that of the second conductive segment 12. Another example is that the density of the material of the first conductive segment 11 is less than the density of the material of the second conductive segment 12. In this way, by setting the density of the first material to be less than the density of the second material, it is also possible to achieve that the density of the first conductive segment 11 is less than that of the second conductive segment 12.

[0050] The materials of the first conductive segment 11 and the second conductive segment 12 can be set according to the actual situation. For example, the first conductive segment 11 can be made of materials such as aluminum or aluminum alloy, and the second conductive segment 12 can be made of materials such as copper or copper alloy. Optionally, in this embodiment, the material of the first conductive segment 11 is aluminum, and the material of the second conductive segment 12 is copper.

[0051] Specifically, the first material is aluminum and the second material is copper. The second conductive segment 12 is made of copper, so that the end of the rotor conductive bar 1 retains the original copper material. This not only makes the end of the rotor conductive bar 1 have advantages such as good mechanical properties, safe and reliable during high-speed rotation, excellent electrical and thermal conductivity, and low end temperature rise, but also keeps the bridging and lead structure of the rotor assembly 100 unchanged, and the reliability can still be guaranteed. The first conductive segment 11 is made of aluminum. The first conductive segment 11 can make full use of the large cooling flow rate and high wind speed at the outlet of the radial ventilation slot 22 of the rotor core 2. Even under high thermal load, it can still maintain a relatively low temperature rise, realize uniform temperature rise of the whole rotor conductive bar 1, and reduce the weight of the rotor conductive bar 1 compared with a fully copper conductive bar. In this way, the rotor deflection and bearing load of the generator can also be reduced accordingly, thereby improving the reliability of the generator. Hereinafter, an example where the material of the first conductive segment 11 is aluminum and the material of the second conductive segment 12 is copper will be introduced.

[0052] And the price of the first material is usually lower than that of the second material. In this way, the rotor conductive bar 1 can only replace the material of the part of the conductive bar located in the iron core slot compared with the existing conductive bar, and still keep the overall existing rotor core 2 unchanged, so as to achieve rapid cost reduction of the generator.

[0053] The first conductive segment 11 is butt - fixed to the second conductive segment 12. The specific fixing method between the first conductive segment 11 and the second conductive segment 12 can be set according to the actual situation. For example, the first conductive segment 11 and the second conductive segment 12 can be fixedly connected by welding, bonding, or hot melting, etc. Optionally, in this embodiment, the first conductive segment 11 and the second conductive segment 12 are fixedly connected by flash welding. Hereinafter, the case where the first conductive segment 11 and the second conductive segment 12 are fixedly connected by flash welding will be taken as an example for introduction.

[0054] Please refer to Figure 1 and Figure 2 , one end of the first conductive segment 11 is butted against one end of the second conductive segment 12, thereby forming a butting joint 13 between the first conductive segment 11 and the second conductive segment 12. The butting joint 13 can be located inside or outside the iron core slot 21.

[0055] Optionally, please refer to Figure 1 and Figure 2 , in this embodiment, the butting joint 13 between the first conductive segment 11 and the second conductive segment 12 is arranged to be inside the iron core slot 21. In this way, setting the butting joint 13 between the first conductive segment 11 and the second conductive segment 12 inside the iron core slot 21 can avoid the butting joint 13 from being subjected to axial tension.

[0056] The right end of the second conductive segment 12a on the left is butted against the left end of the first conductive segment 11 to form a butting joint 13. The butting joint 13 between the second conductive segment 12a on the left and the first conductive segment 11 is the left butting joint 13a; the left end of the second conductive segment 12b on the right is butted against the right end of the first conductive segment 11 to form a butting joint 13. The butting joint 13 between the second conductive segment 12b on the right and the first conductive segment 11 is the right butting joint 13b. The left butting joint 13a and the right butting joint 13b can both be located inside the iron core slot 21. At this time, the size of the first conductive segment 11 in the left - right and up - down directions is smaller than the size of the rotor iron core 2 in the left - right and up - down directions. The first conductive segment 11 is located inside the iron core slot 21. The right end of the second conductive segment 12a on the left extends into the iron core slot 21 from the left, and the left end of the second conductive segment 12b on the right extends into the iron core slot 21 from the right, so that both the left butting joint 13a and the right butting joint 13b are located inside the iron core slot 21.

[0057] The left butting joint 13a and the right butting joint 13b can also both be located outside the iron core slot 21. At this time, the size of the first conductive segment 11 in the left - right and up - down directions is larger than the size of the rotor iron core 2 in the left - right and up - down directions. Both ends of the first conductive segment 11 extend out of the iron core slot 21, so that both the left butting joint 13a and the right butting joint 13b are located outside the iron core slot 21.

[0058] The left docking part 13a and the right docking part 13b can also be arranged such that one is outside the iron core slot 21 and the other is inside the iron core slot 21. At this time, one end of the first conductive segment 11 is inside the iron core slot 21 and the other end extends outside the iron core slot 21, so that one of the left docking part 13a and the right docking part 13b is outside the iron core slot 21 and the other is inside the iron core slot 21.

[0059] Optionally, please refer to Figure 1 and Figure 2 , in this embodiment, the docking part 13 of the first conductive segment 11 and the second conductive segment 12 is arranged at the connection between the iron core slot 21 and the radial ventilation slot 22.

[0060] Specifically, the outer peripheral side of the rotor iron core 2 is usually provided with radial ventilation slots 22 extending along the circumferential direction of the rotor iron core 2. The radial ventilation slots 22 communicate with the iron core slots 21, and a plurality of radial ventilation slots 22 are arranged at intervals along the axial direction of the rotor iron core 2. Since the resistance of the docking part 13 of the first conductive segment 11 and the second conductive segment 12 is greater than that of the base material, arranging the docking part 13 at the connection between the iron core slot 21 and the radial ventilation slot 22 is beneficial to the heat dissipation of the docking part 13 to ensure the uniform temperature of the overall rotor conductive bar 1.

[0061] Furthermore, please refer to Figure 1 and Figure 2 , in this embodiment, the two docking parts 13 of the rotor conductive bar 1 are respectively arranged at the connections between the iron core slot 21 and the two radial ventilation slots 22 located on the outermost sides.

[0062] Specifically, the left docking part 13a is arranged at the connection between the iron core slot 21 and the leftmost radial ventilation slot 22, and the right docking part 13b is arranged at the connection between the iron core slot 21 and the rightmost radial ventilation slot 22. In this way, while ensuring that the two docking parts 13 of the rotor conductive bar 1 can be located at the connections between the iron core slot 21 and the radial ventilation slots 22, it is also beneficial to increase the size of the first conductive segment 11 in the left-right direction.

[0063] Optionally, please refer to Figure 1 and Figure 2 , in this embodiment, the end of the second conductive segment 12 far from the first conductive segment 11 is bent.

[0064] Optionally, in this embodiment, an insulating structure is provided on the outer surface of the rotor conductive bar 1.

[0065] Specifically, after welding the end faces of the first conductive segment 11 and the second conductive segment 12, bending and insulating wrapping are carried out to obtain the rotor conductive bar 1.

[0066] The present invention also provides a rotor assembly, which can be used in a doubly-fed generator. Figure 2 Fig. shows a preferred embodiment of the rotor assembly provided by the present invention.

[0067] Please refer to Figure 1 and Figure 2 , in this embodiment, the rotor assembly 100 includes a rotor conducting bar 1, a rotor core 2 and a rotating shaft 3. The rotor core 2 is sleeved on the rotating shaft 3; at least a part of the first conducting section 11 of the rotor conducting bar 1 is arranged on the rotor core 2, and one end of the second conducting section 12 of the rotor conducting bar 1, which is far from the first conducting section 11, extends beyond the rotor core 2 in the axial direction of the rotor core 2.

[0068] Specifically, the rotor core 2 and the rotating shaft 3 are coaxially arranged. The rotating shaft 3 extends along the left-right direction. The rotor core 2 is sleeved on the middle part of the rotating shaft 3. A plurality of rotor conducting bars 1 are installed on the rotor core 2 along the circumferential direction of the rotor core 2 to form a rotor winding. In this way, when the rotating shaft 3 rotates around the axis in the left-right direction, the rotating shaft 3 can drive the rotor core 2 and the rotor winding to rotate together, thereby generating an induced electromotive force. Among them, since the rotor conducting bar 1 adopts the technical solution of the above embodiment, it has the beneficial effects brought by the technical solution of the above embodiment.

[0069] Optionally, please refer to Figure 2 , in this embodiment, the rotor winding is a double-layer winding.

[0070] The rotor core 2 can be a conventional rotor core. Usually, a core slot 21 is arranged on the rotor core 2. Optionally, please refer to Figure 2 , in this embodiment, a core slot 21 extending along the axial direction of the rotor core 2 is opened on the outer peripheral side surface of the rotor core 2, and the part of the rotor conducting bar 1 arranged on the rotor core 2 is embedded in the core slot 21.

[0071] Specifically, a core slot 21 extending along the left-right direction is opened on the outer peripheral side surface of the rotor core 2. The core slot 21 penetrates the rotor core 2 from left to right, and a plurality of core slots 21 are arranged along the circumferential direction of the rotor core 2. A plurality of rotor conducting bars 1 are embedded in the plurality of core slots 21 to form a rotor winding.

[0072] Optionally, please refer to Figure 2 , in this embodiment, one end of the second conducting section 12 close to the first conducting section 11 extends into the core slot 21.

[0073] In terms of this, the left - right dimension of the first conductive segment 11 is smaller than that of the rotor core 2 in the left - right direction. The first conductive segment 11 is located within the core slot 21. The right end of the left - hand second conductive segment 12a extends into the core slot 21 from the left side, and the left end of the right - hand second conductive segment 12b extends into the core slot 21 from the right side, so that both the left docking joint 13a and the right docking joint 13b are located within the core slot 21. The parts of the left - hand second conductive segment 12a and the right - hand second conductive segment 12b that are outside the core slot 21 respectively form the two ends of the rotor busbar 1. In this way, the ends of the rotor busbar 1 retain the original copper material, which not only makes the ends of the rotor busbar 1 have advantages such as good mechanical properties, safety and reliability during high - speed rotation, excellent electrical and thermal conductivity, and low end - part temperature rise, but also keeps the bridging and lead - wire structure of the rotor assembly 100 unchanged, and the reliability can still be guaranteed. The first conductive segment 11, the part of the left - hand second conductive segment 12a within the core slot 21, and the part of the right - hand second conductive segment 12b within the core slot 21 form the part of the rotor busbar 1 within the core slot 21, which can make full use of the heat - dissipation conditions of the large outlet cooling flow rate and high wind speed of the radial ventilation slots 22 of the rotor core 2. Even under high heat loads, it can still maintain a relatively low temperature rise, achieve uniform temperature rise of the entire rotor busbar 1, and reduce the weight of the rotor busbar 1 compared with a fully - copper busbar. In this way, the rotor deflection and bearing load of the generator can also be correspondingly reduced, thereby improving the reliability of the generator.

[0074] And setting the left docking joint 13a and the right docking joint 13b within the core slot 21 can prevent the left docking joint 13a and the right docking joint 13b from being subjected to axial tension.

[0075] Optionally, please refer to Figure 2 , in this embodiment, radial ventilation slots 22 extending along the circumferential direction of the rotor core 2 are provided on the outer peripheral side surface of the rotor core 2. The radial ventilation slots 22 communicate with the core slot 21, and the docking joint 13 between the second conductive segment 12 and the first conductive segment 11 is located at the connection between the core slot 21 and the radial ventilation slot 22.

[0076] Specifically, the rotor core 2 includes a plurality of rotor laminations 23. The rotor laminations 23 can be silicon steel sheets, etc. The plurality of rotor laminations 23 are sequentially sleeved on the rotating shaft 3. Any two adjacent rotor laminations 23 are spaced apart in the left - right direction to form a docking joint 13 between any two adjacent rotor laminations 23. Since the resistance of the docking joint 13 between the first conductive segment 11 and the second conductive segment 12 is greater than that of the base material, setting the docking joint 13 at the connection between the core slot 21 and the radial ventilation slot 22 is beneficial to the heat dissipation of the docking joint 13 to ensure uniform temperature of the entire rotor busbar 1.

[0077] Furthermore, please refer to Figure 2, in this embodiment, the two docking joints 13 of the rotor conducting bar 1 are respectively arranged at the connection positions of the iron core slot 21 and the two radially ventilating slots 22 located on the outermost sides.

[0078] Specifically, in the rotor iron core 2, the leftmost one of the multiple rotor laminations 23 is the first rotor lamination 23a, and the one adjacent to the first rotor lamination 23a is the second rotor lamination 23b. The radially ventilating slot 22 between the first rotor lamination 23a and the second rotor lamination 23b is the leftmost radially ventilating slot 22. The rightmost one of the multiple rotor laminations 23 is the third rotor lamination 23c, and the one adjacent to the third rotor lamination 23c is the fourth rotor lamination 23d. The radially ventilating slot 22 between the third rotor lamination 23c and the fourth rotor lamination 23d is the rightmost radially ventilating slot 22.

[0079] The left docking joint 13a is located between the first rotor lamination 23a and the second rotor lamination 23b, so that the left docking joint 13a is arranged at the connection position of the iron core slot 21 and the leftmost radially ventilating slot 22. The right docking joint 13b is located between the third rotor lamination 23c and the fourth rotor lamination 23d, so that the right docking joint 13b is arranged at the connection position of the iron core slot 21 and the rightmost radially ventilating slot 22. In this way, while ensuring that both docking joints 13 of the rotor conducting bar 1 can be located at the connection positions of the iron core slot 21 and the radially ventilating slots 22, it is also beneficial to increase the size of the first conducting section 11 in the left-right direction.

[0080] The present invention also provides a generator, which can be a doubly-fed generator. The generator includes a rotor assembly. Since the rotor assembly adopts the technical solution of the above embodiment, it has the beneficial effects brought by the technical solution of the above embodiment.

[0081] The generator further includes a stator assembly. The stator assembly includes a stator iron core and a stator winding. The stator winding is directly connected to a fixed-frequency three-phase power grid, while the rotor winding is connected to the power grid through a bidirectional back-to-back IGBT (Insulated Gate Bipolar Transistor) voltage source converter. By compensating the difference between the mechanical frequency and the electrical frequency through the voltage source converter, variable speed constant frequency control is achieved. In this way, both the stator and the rotor of the generator exchange power with the power grid.

[0082] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made under the inventive concept of the present invention, or direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A rotor conductive bar, used in a rotor assembly, characterized in that: The rotor conductive bar comprises: a first conductive segment, at least a portion of which is used to be disposed on a rotor core of the rotor assembly; a second conductive segment, one end of the second conductive segment butting against one end of the first conductive segment, and one end of the second conductive segment away from the first conductive segment extending beyond the rotor core in the axial direction of the rotor core; The thermal conductivity of the material of the second conductive segment is greater than the thermal conductivity of the material of the first conductive segment; and / or the electrical conductivity of the material of the second conductive segment is greater than the electrical conductivity of the material of the first conductive segment.

2. The rotor conductive bar according to claim 1, characterized in that: The density of the first conductive segments is less than the density of the second conductive segments.

3. The rotor conductive bar according to claim 2, characterized in that: The density of the material of the first conductive segment is less than the density of the material of the second conductive segment.

4. The rotor conductive bar according to any one of claims 1 to 3, characterized in that: The material of the first conductive segment is aluminum, and the material of the second conductive segment is copper.

5. The rotor conductive bar according to any one of claims 1 to 3, characterized in that: Two second conductive segments are provided, and the two second conductive segments are respectively connected to two ends of the first conductive segment.

6. A rotor assembly, characterized in that: include: Rotating shaft; A rotor core, wherein the rotor core is sleeved on the rotating shaft; A rotor conductive bar, wherein the rotor conductive bar is a rotor conductive bar as described in any one of claims 1 to 5, wherein at least a portion of a first conductive segment of the rotor conductive bar is disposed on the rotor core, and an end of a second conductive segment of the rotor conductive bar away from the first conductive segment extends beyond the rotor core in the axial direction of the rotor core.

7. The rotor assembly according to claim 6, characterized in that An iron core slot extending along the axial direction of the rotor core is provided on the outer peripheral side surface of the rotor iron core, and a portion of the rotor conductive row arranged on the rotor iron core is embedded in the iron core slot.

8. The rotor assembly according to claim 7, characterized in that One end of the second conductive segment close to the first conductive segment extends into the core slot.

9. The rotor assembly according to claim 8, characterized in that A radial ventilation groove extending along the circumference of the rotor core is provided on the outer peripheral side surface of the rotor core, the radial ventilation groove is connected with the core slot, and the docking point between the second conductive segment and the first conductive segment is located at the connection point between the core slot and the radial ventilation groove.

10. A generator, characterized in that: Comprising a rotor assembly as described in any one of claims 6-9.

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