Novel magnet yoke

Abstract

The utility model relates to the technical field of generators, in particular to a novel magnet yoke which comprises a magnet yoke body and a plurality of inner side key grooves matched with vertical ribs of a rotor support. And an interelectrode groove is also arranged between two adjacent inner side key grooves. Through the magnet yoke, the strain energy at the notch of the key groove in the inner side of the magnet yoke can be released, and the pulling force borne by the key groove in the inner side of the magnet yoke is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of generators, in particular to a novel magnetic yoke. Background Art

[0002] The yoke is one of the most critical components in a hydro-turbine generator. It secures the magnetic poles on the outside and connects to the rotor frame on the inside, forming a key component of the generator's magnetic circuit. Typically, the yoke is constructed from a laminated structure consisting of several identically shaped yoke sheets, or from stacked, integral steel plates or forgings. To connect to the rotor frame, the yoke's inner circular edge is typically notched, with a corresponding notch on the rotor frame's side. A yoke key connects the two.

[0003] For example, in the prior art, a Chinese utility model patent document with publication number CN220857733U and authorization announcement date of April 26, 2024 is proposed. The technical solution disclosed in the patent document is as follows: a new type of combined yoke key structure for a high-speed pumped storage unit, including a rotor bracket, a yoke and a yoke key, the yoke key including independently arranged radial keys and tangential keys, the rotor bracket and the yoke both have keyways, and after the two are matched, a keying space for the radial key is formed in the middle of the yoke keyway, and a keying space for the tangential key is formed at both ends of the yoke keyway.

[0004] During actual use of the above technical solution, the following problems may arise: when the generator is working, due to the centrifugal force of the magnetic poles and the yoke itself, stress concentration will be formed at the sharp corners of the keyway notch on the inner side of the yoke. Therefore, the sharp corners of the keyway notch on the inner side of the yoke sheet are prone to bending deformation or cracks, which seriously affects the reliability and safety of the generator.

[0005] In order to release the strain energy at the keyway notch on the inner side of the yoke, the current structure is to make a rounded corner smooth transition or adopt a smooth groove design at the sharp corner of the keyway on the inner side of the yoke to reduce the stress concentration of the inner keyway. However, considering the matching relationship between the yoke key and the keyway on the inner side of the yoke, the size of the rounded corner or groove of the inner keyway is limited. In addition, for large-capacity and high-speed generator motors, due to their large centrifugal force, simply reducing their stress concentration is not enough. There is an urgent need for a yoke structure that can meet installation requirements and reduce stress concentration at the keyway. Summary of the Invention

[0006] In order to solve the above technical problems, the utility model proposes a new type of magnetic yoke, which can release the strain energy at the keyway notch on the inner side of the magnetic yoke and reduce the pulling force on the keyway on the inner side of the magnetic yoke.

[0007] The utility model is realized by adopting the following technical solutions:

[0008] A novel magnetic yoke comprises a magnetic yoke body and a plurality of inner keyways for cooperating with vertical ribs of a rotor support; an interpolar groove is further provided between two adjacent inner keyways.

[0009] The interpolar groove includes an arcuate edge, and the arcuate edge is concentric with the inner circular edge of the yoke body.

[0010] The interpolar groove further comprises two oblique edges, one end of each of the two oblique edges is respectively connected to the inner circular edge of the yoke body, and the other end is respectively transitionally connected to the two ends of the arc edge through the arc edge.

[0011] The angle between the oblique edge and the inner circular edge of the yoke body is 45°.

[0012] The inner keyway includes three right-angled sides connected in sequence, and the intersection of two adjacent right-angled sides is a rounded corner or a groove.

[0013] Each inner keyway is matched with the vertical rib of the rotor bracket through a yoke radial key and a yoke tangential key.

[0014] Each inner keyway is matched with the vertical rib of the rotor support through a yoke radial key and two yoke tangential keys.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] 1. The utility model reduces the pulling force on the inner keyway without introducing a new stress concentration point by arranging an interpolar groove between two adjacent inner keyways, thereby fundamentally solving the problem of excessive stress in the inner keyway.

[0017] 2. The interpolar groove includes an arcuate edge. The arrangement of the arcuate edge can not only release the stress of the keyway inside the yoke, but also provide effective support for the edge of the yoke that transmits torque tangentially, thereby achieving a better effect.

[0018] 3. The setting of the bevel edge and the arc edge makes the structure of the inter-pole groove more stable and can better release the strain at the keyway notch on the inner side of the yoke.

[0019] 4. Due to the setting of the inter-pole groove, the intersection of the two adjacent right-angled sides of the inner keyway can be set as a rounded corner or a groove, which can further reduce the stress concentration of the inner keyway.

[0020] 5. The tangential key of the yoke can transmit the torque of the unit. The radial key of the yoke can ensure that the yoke and the rotor bracket remain concentric. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, wherein:

[0022] Figure 1 It is a structural diagram of the utility model;

[0023] Figure 2 This is a connection diagram of the utility model;

[0024] Markings in the figure:

[0025] 1. Inner keyway, 2. Yoke radial key, 3. Interpole groove, 4. Fillet, 5. Bevel edge, 6. Arc edge, 7. Arc edge, 8. Right-angle edge, 9. Yoke tangential key, 10. Yoke body, 11. Rotor bracket, 12. Vertical rib. DETAILED DESCRIPTION

[0026] Example 1

[0027] As a basic embodiment of the present invention, the present invention comprises a novel magnetic yoke, comprising a yoke body 10 and a plurality of inner keyways 1 for mating with vertical ribs 12 of a rotor support 11. Interpolar grooves 3 are also provided between adjacent inner keyways 1. The specific structure of the interpolar grooves 3 is not limited in this embodiment, as long as no new stress concentration points are introduced.

[0028] Example 2

[0029] As a preferred embodiment of the present invention, the present invention includes a novel magnetic yoke, comprising a yoke body 10 and a plurality of inner keyways 1 for mating with vertical ribs 12 of a rotor support 11. An interpolar groove 3 is provided between two adjacent inner keyways 1. The interpolar groove 3 includes an arcuate edge 7 that is concentric with the inner circular edge of the yoke body 10, resulting in a large arc-shaped interpolar groove 3.

[0030] Example 3

[0031] As another preferred embodiment of the present invention, the present invention includes a novel magnetic yoke comprising a yoke body 10 and a plurality of inner keyways 1 for mating with vertical ribs 12 of a rotor support 11. The inner keyways 1 comprise three sequentially connected right-angled sides 8, with the intersection of two adjacent right-angled sides 8 forming a groove. An interpolar groove 3 is also provided between adjacent inner keyways 1.

[0032] Example 4

[0033] As the best embodiment of this utility model, refer to the attached Figure 1The present invention includes a novel magnetic yoke, comprising a yoke body 10 and a plurality of inner keyways 1 for mating with vertical ribs 12 of a rotor support 11. The inner keyway 1 includes three sequentially connected right-angled edges 8. Specifically, the inner keyway 1 may include a first right-angled edge, a second right-angled edge, and a third right-angled edge. The intersection of the first and second right-angled edges is a rounded corner 4, and the intersection of the second and third right-angled edges is also a rounded corner 4.

[0034] An interpolar groove 3 is also provided between two adjacent inner keyways 1. The interpolar groove 3 includes an arcuate edge 7 and two beveled edges 5. The arcuate edge 7 is concentric with the inner circular edge of the yoke body 10. One end of each of the two beveled edges 5 is connected to the inner circular edge of the yoke body 10, and the other end is transitionally connected to the two ends of the arcuate edge 7 via an arcuate edge 6. The beveled edge 5 forms a certain angle with the inner circular edge of the yoke body 10. In this embodiment, the angle can be 45°.

[0035] Refer to the instruction manual Figure 2 , each inner keyway 1 and the vertical rib 12 of the rotor bracket 11 are matched with the yoke radial key 2 and the yoke tangential key 9. Preferably, each inner keyway 1 and the vertical rib 12 of the rotor bracket 11 are matched with a yoke radial key 2 and two yoke tangential keys 9. Among them, the first right-angled side and the second right-angled side are respectively in contact with a yoke tangential key 9 to transmit the torque of the unit; the second right-angled side is in contact with the yoke radial key 2 to keep the yoke and the rotor bracket 11 concentric. A certain amount of tightening is generally set between the two, which is achieved by hot-bonding the yoke.

[0036] To sum up, after reading the utility model document, ordinary technicians in this field can make various other corresponding transformation schemes based on the technical scheme and technical concept of the utility model without creative mental labor, which all fall within the scope of protection of the utility model.

Claims

1. A novel magnetic yoke comprising a magnetic yoke body (10) and a plurality of inner keyways (1) for cooperating with vertical ribs (12) of a rotor support (11); characterized in that: An interpolar groove (3) is also provided between two adjacent inner keyways (1).

2. A new type of magnetic yoke according to claim 1, characterized in that: The interpolar groove (3) comprises an arcuate edge (7), and the arcuate edge (7) is concentric with the inner circular edge of the yoke body (10).

3. A new type of magnetic yoke according to claim 2, characterized in that: The interpolar groove (3) further comprises two oblique edges (5), one end of each of the two oblique edges (5) being connected to the inner circular edge of the yoke body (10), and the other end of each of the two oblique edges being transitionally connected to the two ends of the arc edge (7) via the arc edge (6).

4. A novel magnetic yoke according to claim 3, characterized in that: The included angle between the oblique edge (5) and the inner circular edge of the yoke body (10) is 45°.

5. A novel magnetic yoke according to any one of claims 1 to 4, characterized in that: The inner keyway (1) comprises three right-angled sides (8) connected in sequence, and the intersection of two adjacent right-angled sides (8) is a rounded corner (4) or a groove.

6. The novel magnetic yoke according to claim 2, characterized in that: Each inner keyway (1) and the vertical rib (12) of the rotor bracket (11) are matched with the yoke radial key (2) and the yoke tangential key (9).

7. The novel magnetic yoke according to claim 6, characterized in that: Each inner keyway (1) is matched with the vertical rib (12) of the rotor bracket (11) via a yoke radial key (2) and two yoke tangential keys (9).

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