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 and the first conductive section are arranged along the extension direction of the rotor conducting bar, the cross section area of the second conductive section is larger than that of the first conductive section, and 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. The rotor conducting bar is a variable cross-section rotor conducting bar, and under the condition that the cross-sectional area of the second conducting section is not changed, the cross-sectional area of the first conducting section is reduced, so that the material consumption of the part, located in the iron core groove, of the rotor conducting bar is reduced; under the condition that the cross section area of the first conductive section is not changed, the cross section area of the second conductive section is increased, so that the end loss of the rotor winding can be reduced, and end hot spots are eliminated to perform motor capacity increasing.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of power generation equipment, and in particular 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 unit's electricity cost, wind turbines are developing towards high power. Doubly fed generators are mainly used in wind turbines. The rotor assembly of the doubly fed generator includes a rotor core and a rotor winding. The rotor core is provided with core slots. The middle part of the rotor winding is wound in the core slots of the rotor core, and the two ends of the rotor winding are located outside the core slots of the rotor core. Generally, the end of the rotor winding has a compact structure and poor cooling effect, which makes the temperature rise of the end of the rotor winding more than 20K higher than the temperature rise of the part of the rotor winding located in the core slot.

[0003] At present, the rotor conductive bars used to wind the rotor windings are basically fixed-section structures, and the ends of the rotor conductive bars are the same size as the parts of the rotor conductive bars located in the core slots. Since the hot spots of the rotor windings are at the ends of the rotor windings, the insulation of the rotor conductive bars has requirements for the overall temperature rise, and the temperature of the rotor windings located in the core slots is relatively low, so the fixed-section rotor conductive bars will cause waste of winding materials in the slots. The rotor conductive bars are mostly made of copper or aluminum, and the cost of the rotor conductive bars is relatively high, and the waste of winding materials in the slots will increase the overall cost of the generator. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a rotor conductive bar, a rotor assembly and a generator, aiming to reduce the waste of winding material in the slots or eliminate the end hot spots of the rotor winding to increase the capacity of the motor.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides a rotor conductive bar for a rotor assembly, wherein the rotor conductive bar comprises:

[0006] a first conductive segment, at least a portion of which is used to be disposed on a rotor core of the rotor assembly;

[0007] A second conductive segment, wherein the second conductive segment and the first conductive segment are arranged along an extension direction of the rotor conductive row, a cross-sectional area of ​​the second conductive segment is greater than a cross-sectional area of ​​the first conductive segment, and an end of the second conductive segment away from the first conductive segment exceeds the rotor core in the axial direction of the rotor core.

[0008] In some embodiments, a width of the second conductive segment is greater than a width of the first conductive segment.

[0009] In some embodiments, a thickness of the second conductive segment is greater than a thickness of the first conductive segment.

[0010] In some embodiments, a thickness of the second conductive segment is equal to a thickness of the first conductive segment.

[0011] In some embodiments, the second conductive segment is connected to the first conductive segment, and a connection between the second conductive segment and the first conductive segment is transitioned by a chamfer.

[0012] In some embodiments, the second conductive segment is connected to the first conductive segment, an insulating layer is disposed on the circumferential side surface of the rotor conductive row, and the insulating layer is thickened at the connection between the second conductive segment and the first conductive segment.

[0013] In some embodiments, two second conductive segments are provided, and the two second conductive segments are respectively located at two sides of the first conductive segment in the extension direction of the rotor conductive bar.

[0014] In order to achieve the above object, the present invention further provides a rotor assembly, comprising:

[0015] Rotating shaft;

[0016] A rotor core, wherein the rotor core is sleeved on the rotating shaft;

[0017] A rotor conductive row, wherein the rotor conductive row is the above-mentioned rotor conductive row, at least a portion of a first conductive segment of the rotor conductive row is disposed on the rotor core, and an end of a second conductive segment of the rotor conductive row away from the first conductive segment exceeds the rotor core in the axial direction of the rotor core.

[0018] In some embodiments, a core slot extending along the axial direction of the rotor core is opened on the outer peripheral side surface of the rotor core, and a portion of the rotor conductive bar disposed on the rotor core is embedded in the core slot.

[0019] In some embodiments, at least one end of the first conductive segment extends beyond the rotor core in the axial direction of the rotor core.

[0020] In order to achieve the above object, the present invention also provides a generator, comprising the above rotor assembly.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The rotor conductive bar of the present invention is a variable-section rotor conductive bar, which includes a first conductive segment with a smaller cross-sectional area and a second conductive segment with a larger cross-sectional area. The first conductive segment forms the portion of the rotor conductive bar located in the core slot, and the second conductive segment forms the end of the rotor conductive bar. When the cross-sectional area of ​​the second conductive segment remains unchanged relative to that of the existing rotor conductive bar, the cross-sectional area of ​​the first conductive segment is reduced relative to that of the existing rotor conductive bar, so that the material consumption of the portion of the rotor conductive bar located in the core slot is reduced. By using this variable-section rotor conductive bar to wind the rotor winding, the waste of winding material in the slot of the rotor winding can be reduced. When the cross-sectional area of ​​the first conductive segment remains unchanged relative to that of the existing rotor conductive bar, the cross-sectional area of ​​the second conductive segment is increased relative to that of the existing rotor conductive bar. By using this variable-section rotor conductive bar to wind the rotor winding, the end loss of the rotor winding can be reduced, and the end hot spots of the rotor winding can be eliminated to increase the capacity of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0024] Figure 1 Schematic diagram of the structure of the rotor conductive bar in an embodiment of the present invention;

[0025] Figure 2 Schematic diagram of the structure of the rotor assembly in an embodiment of the present invention.

[0026] Description of the accompanying drawings of the present invention:

[0027] Rotor assembly 100, rotor conductive row 1, first conductive segment 11, second conductive segment 12, left second conductive segment 12a, right second conductive segment 12b, chamfer 13, variable cross-section transition 14, left variable cross-section transition 14a, right variable cross-section transition 14b, end conductive row 15, left end conductive row 15a, right end conductive row 15b, in-slot conductive row 16, rotor core 2, core slot 21, radial ventilation slot 22, rotor lamination 23, rotating shaft 3.

[0028] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0029] As can be seen from the background technology, it is currently necessary to provide a rotor conductive bar, a rotor assembly and a generator that can reduce the waste of winding materials in the slots or eliminate the end hot spots of the rotor winding to increase the capacity of the motor.

[0030] The rotor conductive bar of the present invention is a variable-section rotor conductive bar, which includes a first conductive segment with a smaller cross-sectional area and a second conductive segment with a larger cross-sectional area. The first conductive segment forms the portion of the rotor conductive bar located in the core slot, and the second conductive segment forms the end of the rotor conductive bar. When the cross-sectional area of ​​the second conductive segment remains unchanged relative to that of the existing rotor conductive bar, the cross-sectional area of ​​the first conductive segment is reduced relative to that of the existing rotor conductive bar, so that the material consumption of the portion of the rotor conductive bar located in the core slot is reduced. By using this variable-section rotor conductive bar to wind the rotor winding, the waste of winding material in the slot of the rotor winding can be reduced. When the cross-sectional area of ​​the first conductive segment remains unchanged relative to that of the existing rotor conductive bar, the cross-sectional area of ​​the second conductive segment is increased relative to that of the existing rotor conductive bar. By using this variable-section rotor conductive bar to wind the rotor winding, the end loss of the rotor winding can be reduced, and the end hot spots of the rotor winding can be eliminated to increase the capacity of the motor.

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] The present invention provides a rotor conductive bar, which can be used for a rotor assembly of a doubly-fed generator. Figure 1 A preferred embodiment of the rotor conductive bar provided by the present invention is shown. Figure 2 A preferred embodiment of the rotor assembly provided by the present invention is shown.

[0035] See also Figure 1 and Figure 2 The rotor conductive bar 1 includes a first conductive segment 11 and a second conductive segment 12. At least a portion of the first conductive segment 11 is used to be arranged on the rotor core 2 of the rotor assembly 100. The second conductive segment 12 and the first conductive segment 11 are arranged along the extension direction of the rotor conductive bar 1. The cross-sectional area of ​​the second conductive segment 12 is greater than the cross-sectional area of ​​the first conductive segment 11. One end of the second conductive segment 12 away from the first conductive segment 11 exceeds the rotor core 2 in the axial direction of the rotor core 2.

[0036] Specifically, the rotor assembly 100 includes a rotor core 2 and a rotor winding, wherein the rotor core 2 is generally cylindrical. The rotor winding is wound on the rotor core 2, and the rotor winding is wound by a plurality of rotor conductive bars 1, which are arranged along the circumference of the rotor core 2 to form the rotor winding.

[0037] The middle part of the rotor conductive bar 1 is arranged on the rotor core 2, and a core slot 21 is usually provided on the outer peripheral side of the rotor core 2. The part of the rotor conductive bar 1 arranged on the rotor core 2 (i.e., the middle part of the rotor conductive bar 1) is embedded in the core slot 21. The part of the rotor conductive bar 1 located in the core slot 21 is defined as the in-slot conductive bar 16 below. In this way, the in-slot conductive bars 16 of multiple rotor conductive bars 1 form the part of the rotor winding located in the core slot 21. The following will take the core slot 21 provided on the rotor core 2 for accommodating the rotor conductive bar 1 as an example for description.

[0038] The dimension of the rotor conductive bar 1 in the axial direction of the rotor core 2 is larger than the dimension of the rotor core 2 in the axial direction of the rotor core 2, so that both ends of the rotor conductive bar 1 extend beyond the rotor core 2 in the axial direction of the rotor core 2. The portion of the rotor conductive bar 1 extending beyond the rotor core 2 is defined as two end conductive bars 15 below, so that the end conductive bars 15 of multiple rotor conductive bars 1 form two ends of the rotor winding.

[0039] The cross-section of the rotor conductive bar 1 is a cross-section perpendicular to the extension direction of the rotor conductive bar 1. The rotor conductive bar 1 can be divided into multiple conductive segments along the extension direction of the rotor conductive bar 1. The multiple conductive segments of the rotor conductive bar 1 include a first conductive segment 11 and a second conductive segment 12 with different cross-sectional areas to form a variable-section rotor conductive bar 1.

[0040] When the rotor conductive bar 1 is mounted on the rotor core 2, at least part of the first conductive segment 11 is embedded in the core slot 21, so that at least part of the in-slot conductive bar 16 is formed by the first conductive segment 11. The end of the second conductive segment 12 away from the first conductive segment 11 extends beyond the rotor core 2 in the axial direction of the rotor core 2, so that at least part of the end conductive bar 15 is formed by the second conductive segment 12. Since the cross-sectional area of ​​the second conductive segment 12 is larger than the cross-sectional area of ​​the first conductive segment 11, the cross-sectional area of ​​at least part of the end conductive bar 15 is larger than the cross-sectional area of ​​at least part of the in-slot conductive bar 16. When the cross-sectional area of ​​the second conductive segment 12 (i.e., the end conductive bar 15) remains unchanged relative to the existing rotor conductive bar, the cross-sectional area of ​​the first conductive segment 11 (i.e., the in-slot conductive bar 16) is reduced relative to the existing rotor conductive bar, so that the material consumption of the in-slot conductive bar 16 is reduced. By using such a variable-section rotor conductive bar 1 to wind the rotor winding, the waste of the in-slot winding material of the rotor winding can be reduced. When the cross-sectional area of ​​the first conductive segment 11 (i.e., the in-slot conductive bar 16) remains unchanged relative to the existing rotor conductive bar, the cross-sectional area of ​​the second conductive segment 12 (i.e., the end conductive bar 15) is increased relative to the existing rotor conductive bar. By using such a variable-section rotor conductive bar 1 to wind the rotor winding, the end loss of the rotor winding can be reduced, and the end hot spots of the rotor winding can be eliminated to increase the capacity of the motor.

[0041] The rotor conductive bar 1 of the present invention is a variable-section rotor conductive bar 1, and the rotor conductive bar 1 includes a first conductive segment 11 with a smaller cross-sectional area and a second conductive segment 12 with a larger cross-sectional area. The first conductive segment 11 forms the portion of the rotor conductive bar 1 located in the core slot 21, and the second conductive segment 12 forms the end of the rotor conductive bar 1; when the cross-sectional area of ​​the second conductive segment 12 remains unchanged relative to that of the existing rotor conductive bar, the cross-sectional area of ​​the first conductive segment 11 is reduced relative to that of the existing rotor conductive bar, so that the material consumption of the portion of the rotor conductive bar 1 located in the core slot 21 is reduced, and the use of such a variable-section rotor conductive bar 1 to wind the rotor winding can reduce the waste of winding materials in the slot of the rotor winding; when the cross-sectional area of ​​the first conductive segment 11 remains unchanged relative to that of the existing rotor conductive bar, the cross-sectional area of ​​the second conductive segment 12 is increased relative to that of the existing rotor conductive bar, and the use of such a variable-section rotor conductive bar 1 to wind the rotor winding can reduce the end loss of the rotor winding, eliminate the end hot spots of the rotor winding, and increase the capacity of the motor.

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

[0043] There are many specific configuration methods to achieve that the cross-sectional area of ​​the second conductive segment 12 is larger than the cross-sectional area of ​​the first conductive segment 11. For example, the width of the second conductive segment 12 can be set to be larger than the width of the first conductive segment 11, so that the cross-sectional area of ​​the second conductive segment 12 is larger than the cross-sectional area of ​​the first conductive segment 11, wherein the width of the rotor conductive bar 1 is the dimension of the rotor conductive bar 1 in the slot width direction of the core slot 21; the thickness of the second conductive segment 12 can be set to be larger than the thickness of the first conductive segment 11, so that the cross-sectional area of ​​the second conductive segment 12 is larger than the cross-sectional area of ​​the first conductive segment 11, wherein the thickness of the rotor conductive bar 1 is the dimension of the rotor conductive bar 1 in the slot depth direction of the core slot 21; the width and thickness of the second conductive segment 12 can be set to be larger than the width and thickness of the first conductive segment 11, respectively, so that the cross-sectional area of ​​the second conductive segment 12 is larger than the cross-sectional area of ​​the first conductive segment 11; and a hole structure extending along the first conductive segment 11 can be provided on the first conductive segment 11, so that the cross-sectional area of ​​the second conductive segment 12 is larger than the cross-sectional area of ​​the first conductive segment 11.

[0044] Optionally, see Figure 1 and Figure 2 In some embodiments, the thickness of the second conductive segment 12 is equal to the thickness of the first conductive segment 11 .

[0045] Specifically, the rotor conductive bar 1 may be a fixed thickness structure, that is, the thicknesses of the multiple conductive segments of the rotor conductive bar 1 are equal, so that the thickness of the second conductive segment 12 is equal to the thickness of the first conductive segment 11, and the width of the second conductive segment 12 is set to be greater than the width of the first conductive segment 11, so that the cross-sectional area of ​​the second conductive segment 12 is greater than the cross-sectional area of ​​the first conductive segment 11. When the rotor conductive bar 1 with a fixed thickness structure is wound with multiple layers of windings, two rotor conductive bars 1 adjacent to each other in the slot depth direction of the core slot 21 can be closely fitted.

[0046] The second conductive segment 12 and the first conductive segment 11 are arranged along the extension direction of the rotor conductive row 1, and the second conductive segment 12 can be directly connected to the first conductive segment 11; the second conductive segment 12 can also be arranged at intervals with the first conductive segment 11, and one or more conductive segments are arranged between the second conductive segment 12 and the first conductive segment 11. For example, the rotor conductive row 1 also includes a third conductive segment, and the two ends of the third conductive segment are respectively connected to the second conductive segment 12 and the first conductive segment 11. The cross-sectional area of ​​the third conductive segment may not be equal to the cross-sectional area of ​​the second conductive segment 12 and the cross-sectional area of ​​the first conductive segment 11, and the cross-sectional area of ​​the third conductive segment may also be gradual.

[0047] Optionally, see Figure 1 and Figure 2In some embodiments, the second conductive segment 12 is connected to the first conductive segment 11 , and the connection between the second conductive segment 12 and the first conductive segment 11 is transitioned through a chamfer 13 .

[0048] Specifically, the second conductive segment 12 is directly connected to the first conductive segment 11, and a variable cross-section transition 14 is formed between the second conductive segment 12 and the first conductive segment 11. A chamfer 13 such as a round chamfer or an inclined chamfer is provided at the variable cross-section transition 14, which can avoid stress concentration at the variable cross-section transition 14 of the rotor conductive row 1. The following will take the direct connection between the second conductive segment 12 and the first conductive segment 11 as an example for description.

[0049] An insulating layer such as insulating paint or insulating tape is usually provided on the circumferential side surface of the rotor conductive bar 1. The following description will be made by taking the insulating layer as the insulating tape and the rotor conductive bar 1 as an example of being wrapped with the insulating tape. Optionally, in some embodiments, the second conductive segment 12 is connected to the first conductive segment 11, and an insulating layer is provided on the circumferential side surface of the rotor conductive bar 1. The portion of the insulating layer provided at the connection between the second conductive segment 12 and the first conductive segment 11 is thickened.

[0050] Specifically, the insulating layer covers the first conductive segment 11, the second conductive segment 12, and the variable cross-section transition 14. Compared with the portion of the insulating layer arranged at the second conductive segment 12 and the first conductive segment 11, the portion of the insulating layer arranged at the variable cross-section transition 14 is thickened. In this way, the insulation wrapping at the variable cross-section transition 14 is specially treated and strengthened, which is conducive to ensuring the insulation effect at the variable cross-section transition 14.

[0051] The specific manufacturing method of the variable cross-section rotor conductive bar 1 can be set according to actual conditions. For example, the variable cross-section rotor conductive bar 1 can be fixedly connected by multiple conductive segments through welding or the like, so as to splice the multiple conductive segments into the variable cross-section rotor conductive bar 1. Optionally, in this embodiment, the rotor conductive bar 1 is integrally formed.

[0052] Specifically, the variable-section rotor conductive bar 1 can be manufactured from a bar material through the processes of primary drawing (large cross-section), secondary drawing (small cross-section), straightening, annealing, etc. Compared with the existing extrusion process of the fixed-section rotor conductive bar, the processing technology of the variable-section rotor conductive bar 1 only has one more secondary drawing process, and the molds are also two large and small molds. In this way, the processing technology of the variable-section rotor conductive bar 1 is basically the same as the existing extrusion process of the fixed-section rotor conductive bar, without special processes, and high production efficiency. In addition, the variable-section rotor conductive bar 1 is integrally formed, so that the structural strength of the variable-section rotor conductive bar 1 is the same as the structural strength of the fixed-section rotor conductive bar, which can meet the high-speed rotation conditions of the generator rotor.

[0053] After the variable-section rotor conductive bar 1 is processed and manufactured through the above steps, the coil is bent and expanded. This process is the same as that of conventional products. Then, when the variable-section rotor conductive bar 1 is insulated and wrapped, the insulation wrapping at the variable-section transition 14 requires special treatment and strengthening.

[0054] The rotor conductive bar 1 includes a first conductive segment 11 and a second conductive segment 12. The rotor conductive bar 1 may include only one first conductive segment 11 and one second conductive segment 12. Figure 1 In some embodiments, the rotor conductive bar 1 includes a first conductive segment 11 and a second conductive segment 12 .

[0055] Specifically, the axial direction of the rotor core 2 is defined as the left-right direction below, and the two end conductive bars 15 of the rotor conductive bar 1 are respectively the left end conductive bar 15a and the right end conductive bar 15b. The left end of the first conductive segment 11 is connected to the second conductive segment 12, and the right end of the first conductive segment 11 exceeds the rotor core 2 to the right, so that the part of the first conductive segment 11 that exceeds the rotor core 2 to the right forms the right end conductive bar 15b. The right end of the second conductive segment 12 can be located in the core slot 21, so that the second conductive segment 12 and the part of the first conductive segment 11 located in the core slot 21 form the in-slot conductive bar 16, and the part of the second conductive segment 12 located outside the core slot 21 forms the left end conductive bar 15a. The second conductive segment 12 can also be located on the left side of the rotor core 2, and the left end of the first conductive segment 11 exceeds the rotor core 2 to the left, so that the part of the first conductive segment 11 located in the core slot 21 forms the in-slot conductive bar 16, and the part of the first conductive segment 11 that exceeds the rotor core 2 to the left and the second conductive segment 12 form the left end conductive bar 15a.

[0056] The rotor conductive bar 1 may also include two second conductive segments 12. Figure 2 In some embodiments, two second conductive segments 12 are provided, and the two second conductive segments 12 are respectively located on both sides of the first conductive segment 11 in the extension direction of the rotor conductive bar 1 .

[0057] Specifically, the first conductive segment 11 is usually arranged to extend along the axial direction of the rotor core 2, and the rotor conductive row 1 includes two second conductive segments 12, which are respectively located on the left and right sides of the first conductive segment 11, and the two ends of the first conductive segment 11 are respectively connected to the two second conductive segments 12, and the two second conductive segments 12 are respectively away from the two ends of the first conductive segment 11 and extend beyond the rotor core 2 to the left and right. The following will take the example of two second conductive segments 12 being provided as an example for introduction.

[0058] The one of the two second conductive segments 12 located on the left side of the first conductive segment 11 is the left second conductive segment 12a, and the one located on the right side of the first conductive segment 11 is the right second conductive segment 12b. The right end of the left second conductive segment 12a is connected to the left end of the first conductive segment 11, and the left end of the left second conductive segment 12a exceeds the rotor core 2 to the left. The connection between the left second conductive segment 12a and the first conductive segment 11 forms a variable cross-section transition 14, and the variable cross-section transition 14 between the left second conductive segment 12a and the first conductive segment 11 is the left variable cross-section transition 14a. Similarly, the left end of the right second conductive segment 12b is connected to the right end of the first conductive segment 11, and the right end of the right second conductive segment 12b exceeds the rotor core 2 to the right. The connection between the right second conductive segment 12b and the first conductive segment 11 forms a variable cross-section transition 14, and the variable cross-section transition 14 between the right second conductive segment 12b and the first conductive segment 11 is the right variable cross-section transition 14b.

[0059] The variable cross-section transition 14 may be located inside the core slot 21 or outside the core slot 21. Figure 2 In some embodiments, the variable cross-section transition 14 between the first conductive segment 11 and the second conductive segment 12 is used to be arranged outside the core slot 21. That is, the end conductive bar 15 of the rotor conductive bar 1 is a variable cross-section, and the slot conductive bar 16 of the rotor conductive bar 1 is a fixed cross-section, and the size of the slot conductive bar 16 matches the size of the core slot 21. If the slot conductive bar 16 is set to a fixed cross-section, the size of the core slot 21 does not need to be changed and can be switched freely, so that the rotor conductive bar 1 has better versatility.

[0060] The rotor conductive bar 1 has a left variable cross-section transition point 14a and a right variable cross-section transition point 14b. The left variable cross-section transition point 14a and the right variable cross-section transition point 14b can be both located outside the core slot 21. At this time, the left-right and upward dimensions of the first conductive segment 11 are greater than the left-right and upward dimensions of the rotor core 2. Both ends of the first conductive segment 11 extend out of the core slot 21, so that the portion of the first conductive segment 11 located in the core slot 21 forms an in-slot conductive bar 16, the portion of the first conductive segment 11 that exceeds the rotor core 2 to the left and the second conductive segment 12a on the left form a left end conductive bar 15a, and the portion of the first conductive segment 11 that exceeds the rotor core 2 to the right and the second conductive segment 12b on the right form a right end conductive bar 15b.

[0061] The left variable cross-section transition point 14a may also be located in the core slot 21, while the right variable cross-section transition point 14b is located outside the core slot 21. At this time, the right end of the left second conductive segment 12a is located in the core slot 21, and the right end of the first conductive segment 11 extends to the right beyond the rotor core 2, so that the first conductive segment 11 and the left second conductive segment 12a located in the core slot 21 form an in-slot conductive bar 16, the left second conductive segment 12a extends to the left beyond the rotor core 2 to form a left end conductive bar 15a, and the first conductive segment 11 extends to the right beyond the rotor core 2 and the right second conductive segment 12b form a right end conductive bar 15b.

[0062] The left variable cross-section transition point 14a can also be located outside the core slot 21, while the right variable cross-section transition point 14b is located inside the core slot 21. At this time, the left end of the right second conductive segment 12b is located inside the core slot 21, and the left end of the first conductive segment 11 extends to the left beyond the rotor core 2, so that the first conductive segment 11 and the right second conductive segment 12b located inside the core slot 21 form an in-slot conductive bar 16, the part of the first conductive segment 11 extending to the left beyond the rotor core 2 and the left second conductive segment 12a form a left end conductive bar 15a, and the part of the right second conductive segment 12b extending to the right beyond the rotor core 2 forms a right end conductive bar 15b.

[0063] Optionally, see Figure 1 and Figure 2 In some embodiments, the end of the second conductive segment 12 away from the first conductive segment 11 is bent.

[0064] The present invention also provides a rotor assembly, which can be used in a double-fed generator. Figure 2 A preferred embodiment of the rotor assembly provided by the present invention is shown.

[0065] See also Figure 1 and Figure 2 In some embodiments, the rotor assembly 100 includes a rotor conductive bar 1, a rotor core 2 and a rotating shaft 3, wherein the rotor core 2 is sleeved on the rotating shaft 3; at least a portion of a first conductive segment 11 of the rotor conductive bar 1 is disposed on the rotor core 2, and an end of a second conductive segment 12 of the rotor conductive bar 1 away from the first conductive segment 11 extends beyond the rotor core 2 in the axial direction of the rotor core 2.

[0066] Specifically, the rotor core 2 is coaxially arranged with the rotating shaft 3, the rotating shaft 3 is extended in the left-right direction, the rotor core 2 is sleeved in the middle of the rotating shaft 3, and a plurality of rotor conductive bars 1 are installed on the rotor core 2 along the circumference of the rotor core 2 to form a rotor winding, so that when the rotating shaft 3 rotates along the left-right upward axis, the rotating shaft 3 can drive the rotor core 2 and the rotor winding to rotate together, thereby generating an induced potential. Among them, since the rotor conductive bar 1 adopts the technical solution of the above embodiment, it has the beneficial effects brought by the technical solution of the above embodiment.

[0067] Optionally, see Figure 2 In some embodiments, the rotor winding is a double-layer winding.

[0068] The rotor core 2 may be a conventional rotor core, and the rotor core 2 is generally provided with a core slot 21. Figure 2 In some embodiments, 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 a portion of the rotor conductive bar 1 disposed on the rotor core 2 is embedded in the core slot 21.

[0069] Specifically, a core slot 21 extending in the left-right direction is opened on the outer circumferential side surface of the rotor core 2. The core slot 21 penetrates the rotor core 2 from left to right, and there are multiple core slots 21 arranged along the circumference of the rotor core 2. Multiple rotor conductive bars 1 are embedded in the multiple core slots 21 to form a rotor winding.

[0070] Optionally, see Figure 2 In some embodiments, radial ventilation slots 22 extending along the circumference of the rotor core 2 are provided on the outer peripheral side surface of the rotor core 2 , and the radial ventilation slots 22 are connected to the core slots 21 .

[0071] Specifically, the rotor core 2 includes a plurality of rotor laminations 23 , which may be silicon steel sheets or the like. The plurality of rotor laminations 23 are sequentially sleeved on the rotating shaft 3 , and any two adjacent rotor laminations 23 are spaced apart in the left and right directions upward to form a radial ventilation slot 22 between any two adjacent rotor laminations 23 .

[0072] Optionally, see Figure 2 In some embodiments, at least one end of the first conductive segment 11 extends beyond the rotor core 2 in the axial direction of the rotor core 2 .

[0073] In particular, the left end of the first conductive segment 11 may extend beyond the rotor core 2 toward the left while the right end is located in the core slot 21; the right end of the first conductive segment 11 may extend beyond the rotor core 2 toward the right while the left end is located in the core slot 21; the left end and right end of the first conductive segment 11 may extend beyond the rotor core 2 toward the left and right respectively. The following will take the example that the left end and right end of the first conductive segment 11 extend beyond the rotor core 2 toward the left and right respectively as an example.

[0074] The left-right and upward dimensions of the first conductive segment 11 are larger than the left-right and upward dimensions of the rotor core 2. Both ends of the first conductive segment 11 extend out of the core slot 21. Thus, the left variable cross-section transition 14a and the right variable cross-section transition 14b are respectively located on the left and right sides of the rotor core 2, so that the end conductive bar 15 of the rotor conductive bar 1 is a variable cross-section, and the in-slot conductive bar 16 of the rotor conductive bar 1 is a fixed cross-section, and the size of the in-slot conductive bar 16 matches the size of the core slot 21. When the in-slot conductive bar 16 is set to a fixed cross-section, the size of the core slot 21 does not need to be changed and can be switched freely, so that the rotor conductive bar 1 has better versatility.

[0075] The rotor winding uses a variable-section rotor conductive bar 1, which can reduce the amount of winding material in the slot of the rotor winding to a limited extent while meeting the temperature rise of the generator, thereby achieving a significant cost reduction. At the same time, the rotor hotspot of the generator is generally at the end of the winding, so the cross-sectional area of ​​the conductive bar at the end of the winding can be increased to reduce current density and loss, eliminate motor hotspots, and increase motor capacity.

[0076] The present invention also provides a generator, which may 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.

[0077] The generator also includes a stator assembly, which includes a stator core and a stator winding. The stator winding is directly connected to the 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. The difference between the mechanical frequency and the electrical frequency is compensated by the voltage source converter to achieve variable speed constant frequency control, so that the stator and rotor of the generator can exchange power with the power grid.

[0078] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are 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, wherein the second conductive segment and the first conductive segment are arranged along an extension direction of the rotor conductive row, a cross-sectional area of ​​the second conductive segment is greater than a cross-sectional area of ​​the first conductive segment, and an end of the second conductive segment away from the first conductive segment exceeds the rotor core in the axial direction of the rotor core.

2. The rotor conductive bar according to claim 1, characterized in that: The width of the second conductive segment is greater than the width of the first conductive segment; and / or the thickness of the second conductive segment is greater than the thickness of the first conductive segment.

3. The rotor conductive bar according to claim 1, characterized in that: The thickness of the second conductive segment is equal to the thickness of the first conductive segment.

4. The rotor conductive bar according to any one of claims 1 to 3, characterized in that: The second conductive segment is connected to the first conductive segment, and a connection between the second conductive segment and the first conductive segment is transitioned by a chamfer.

5. The rotor conductive bar according to any one of claims 1 to 3, characterized in that: The second conductive segment is connected to the first conductive segment, an insulating layer is arranged on the circumferential side surface of the rotor conductive row, and the insulating layer is thickened at the connection between the second conductive segment and the first conductive segment.

6. 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 located at two sides of the first conductive segment in the extending direction of the rotor conductive bar.

7. 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 6, 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.

8. The rotor assembly according to claim 7, 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.

9. The rotor assembly according to claim 7, characterized in that: At least one end of the first conductive segment extends beyond the rotor core in the axial direction of the rotor core.

10. A generator, characterized in that: Comprising a rotor assembly as described in any one of claims 7-9.

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