Rotor punching sheet structure, motor rotor and motor

Abstract

The utility model provides a rotor punching sheet structure, which can effectively improve the performance and the reliability of a motor, a plurality of magnetic steel grooves are arranged on a rotor punching sheet, each magnetic steel groove is formed by sequentially connecting a plurality of edge sections, and the edge sections are smoothly connected through arcs; two groups of first grooves and two groups of second grooves are symmetrically formed in the magnetic steel groove in the axial direction; the first groove is arranged at the outer side edge of the magnetic steel groove, and the second groove is arranged at the inner side edge of the magnetic steel groove; the first grooves protrude towards the outer side, and the first grooves are parallel to the outer side edges of the magnetic steel grooves. The second groove protrudes towards the inner side and is arranged in the direction opposite to the direction of the first groove.

Description

Technical Field

[0001] The utility model relates to the technical field of motor rotors, in particular to a rotor punching structure, a motor rotor and a motor. Background Art

[0002] In modern industrial applications, the working environment of motors is becoming more and more complex and changeable. In addition to requiring the motor to show excellent performance under rated conditions, it must also ensure that the motor can still maintain its performance under special conditions, such as short-term overload at rated speed or overload when the motor is overspeeding. However, these special conditions often lead to an increase in motor current. For permanent magnet synchronous motors, the increase in current will not only cause the motor temperature to rise, but may also cause more serious problems.

[0003] When the current increases, especially in permanent magnet synchronous motors, the negative d-axis component of the current will generate a reverse magnetic field on the permanent magnet. This reverse magnetic field is not evenly distributed around the magnetic steel slots, and its unevenness may cause the working point of the magnetic steel to move below the inflection point of its demagnetization curve. Once this happens, the magnetic steel may suffer irreversible demagnetization, which will seriously affect the performance of the motor and may trigger a vicious cycle, eventually causing the motor to fail to work properly. Utility Model Content

[0004] The utility model aims to solve the problem of motor failure caused by demagnetization, and provides a rotor punching structure that can eliminate magnetic steel demagnetization, thereby effectively improving the performance and reliability of the motor.

[0005] In order to solve the above technical problems, the utility model provides a rotor punching structure, on which a plurality of magnetic steel slots are arranged, wherein the magnetic steel slots are composed of a plurality of edge segments connected in sequence, and each edge segment is smoothly connected by an arc;

[0006] Two groups of first grooves and two groups of second grooves are axially symmetrically arranged on the magnetic steel groove; the first grooves are arranged on the outer side of the magnetic steel groove, and the second grooves are arranged on the inner side of the magnetic steel groove;

[0007] The first groove protrudes outward, and the first groove is arranged parallel to the outer side of the magnetic steel groove; the second groove protrudes inward, and is arranged opposite to the first groove.

[0008] In a preferred embodiment, the first groove, the second groove and the edge section of the magnetic steel groove are connected by an arc transition.

[0009] In a preferred embodiment, grooves are arranged at the four corners of the magnetic steel slot, and two groups of first grooves and two groups of second grooves are arranged at the upper and lower parts.

[0010] In a preferred embodiment, the first groove and the second groove are provided at any position of the outer side and the inner side of the magnetic steel groove.

[0011] In a preferred embodiment, the number of grooves in a single group of first grooves is set to 1-3; the number of grooves in a single group of second grooves is set to 1-3.

[0012] In a preferred embodiment, the length of the first groove is set to 1 / 30-1 / 15 of the length of the magnetic steel groove.

[0013] In a preferred embodiment, the number of magnetic steel slots provided on the rotor punching is greater than or equal to 4.

[0014] In a preferred embodiment, the magnetic steel slots are distributed in a straight line on the rotor punching sheets.

[0015] The utility model also provides a motor rotor, comprising the rotor punching structure.

[0016] The utility model also provides a motor, comprising the motor rotor.

[0017] Compared with the prior art, the technical solution of the utility model has the following beneficial effects:

[0018] 1. The magnetic steel slot is composed of multiple side segments connected in sequence, and each side segment is smoothly connected by an arc. This design helps to reduce stress concentration and improve the overall strength of the structure.

[0019] 2. Raised grooves are designed at the four corners of the magnetic steel slot. Such grooves help to weaken the reverse magnetic field generated by the current and reduce the demagnetization effect on the magnetic steel.

[0020] 3. The four corner grooves and the edge lines of the magnetic steel slots are smoothly transitioned. This transition method can reduce stress concentration, improve the strength of the connection, reduce transition stress, and thus improve the reliability of the entire rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the rotor punching structure in the preferred embodiment of the utility model.

[0022] Explanation of the reference numerals: 1. rotor punching sheet; 2. magnetic steel slot; 21. outer edge; 22. inner edge; 23. edge segment; 24. arc; 3. first groove; 4. second groove; 5. magnetic steel. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model; it is obvious that the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the utility model without making creative work are within the scope of protection of the utility model.

[0024] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present utility model, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "provided with", "installed / connected", "connected", etc. should be understood in a broad sense. For example, "connection" can be a wall-mounted connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium. It can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to specific circumstances.

[0026] refer to Figure 1 , this embodiment provides a rotor punching 1 structure, which is mainly used for motor rotors and motors. When the motor is running, the current has components in the d-axis and q-axis directions. The d-axis direction is perpendicular to the edge of the magnetic steel 5, and the q-axis direction has a counterclockwise angle with the d-axis direction. The size of the angle is an electrical cycle angle, which is converted into a mechanical angle of 360° / (2*P) / 2, where P is the number of pole pairs of the motor. The component of the current in the negative direction of the d-axis will generate a reverse magnetic field of the magnetic steel 5. Therefore, the embodiment provides a rotor punching 1 structure that can eliminate the demagnetization of the magnetic steel 5. Through the reasonable structural layout of the rotor punching 1, the irreversible demagnetization of the magnetic steel 5 caused by the reverse current magnetic field caused by the sudden increase of current under specific working conditions such as short-term overload at rated speed, or overload under motor overspeed is eliminated. At the same time, the strength of the connection is improved and the transition stress is reduced.

[0027] A plurality of magnetic steel slots 2 are arranged on the rotor sheet 1. The magnetic steel slots 2 are arranged in a straight line on the rotor sheet 1, which helps to simplify the magnetic circuit design and improve the uniformity of the magnetic field. The number of magnetic steel slots 2 arranged on the rotor sheet 1 is greater than or equal to 4.

[0028] The magnetic steel slot 2 is used to place the magnetic steel 5. The magnetic steel slot 2 is formed by a plurality of side segments 23 connected in sequence. Each side segment 23 is smoothly connected by an arc 24, which helps to reduce stress concentration and improve the overall strength of the structure.

[0029] Raised grooves are arranged at the four corners of the magnetic steel slot 2 to weaken the reverse magnetic field generated by the current. The grooves arranged at the four corners are transitioned to the corresponding edge lines of the magnetic steel slot 2 with arcs 24 to improve the strength of the connection and reduce the transition stress. In addition, when the motor is subjected to a short-term overload current shock and the reverse magnetic field inside the motor is too large, the reverse magnetic field at the four corners of the magnetic steel 5 is usually greater than that at the other edge lines. The raised grooves at the four corners of the magnetic steel slot 2 are used to weaken the unreasonable reverse magnetic field here to avoid irreversible demagnetization caused by the working point of the magnetic steel 5 moving below the inflection point of the demagnetization curve of the magnetic steel 5.

[0030] Protruding grooves at the four corners of the magnetic steel slot 2 not only help optimize the magnetic circuit, but also enhance the mechanical connection of the rotor punching sheet 1, thereby improving the mechanical strength and impact resistance of the rotor.

[0031] The specific structure of the groove on the magnetic steel slot 2 is that the magnetic steel slot 2 includes an outer side 21 and an inner side 22. The outer side 21 refers to the position of the magnetic steel slot 2 that is farther from the center relative to the center line of the rotor, that is, the side close to the outer diameter of the rotor. The inner side refers to the position of the magnetic steel slot 2 that is closer to the center relative to the center line of the rotor. Two groups of first grooves 3 and two groups of second grooves 4 are axially symmetrically arranged on the magnetic steel slot 2; the first groove 3 is arranged on the outer side 21 of the magnetic steel slot 2, and the second groove 4 is arranged on the inner side 22 of the magnetic steel slot 2.

[0032] The first groove 3 is arranged at two corners of the outer side 21 of the magnetic steel slot 2, and is arranged in a mirror symmetrical manner. The first groove 3 is arranged to bulge outward, and the first groove 3 and the magnetic steel slot 2 are transitionally connected by an arc 24 through their corresponding side segments 23. The first groove 3 is arranged on the outer side 21 to increase the magnetic resistance on the magnetic circuit. The first groove 3 is preferably arranged on the corner, and can also be adjusted to be arranged at any position of the outer side 21 according to actual conditions. The number of grooves in the single group of first grooves 3 is set at 1-3.

[0033] The first groove 3 is arranged parallel to the outer side 21 of the magnetic steel groove 2, and the size of the first groove 3 can be selected according to the length of the magnetic steel groove 2, which is the length of the outer side 21 of the magnetic steel groove 2. The length of the first groove 3 is generally set to 1 / 30-1 / 15 of the length of the magnetic steel groove 2. With respect to the magnetic steel 5, the forward magnetic field at the four corners is generally weaker than that in the middle. When the reverse magnetic field suddenly increases, the field strength at the four corners will weaken faster than that in the middle. By adding the first groove 3 at the corner of the outer side 21 of the magnetic steel groove 2, the magnetic resistance at this position can be changed, thereby eliminating the risk point at this location.

[0034] Similarly, the second groove 4 is arranged at two corners of the inner side 22 of the magnetic steel groove 2, and is arranged in a mirror-symmetrical manner. The second groove 4 protrudes inwardly and is arranged in the opposite direction to the first groove 3. The second groove 4 and the magnetic steel groove 2 are transitionally connected by an arc 24 through their corresponding edge segments 23. The second groove 4 is arranged on the inner side 22 to increase the magnetic resistance on the magnetic circuit. The second groove 4 is preferably arranged on the corner, and can also be adjusted to be arranged at any position of the inner side 22 according to actual conditions. The number of grooves in the single group of first grooves 3 is set at 1-3.

[0035] By providing grooves on the magnetic steel slot 2 to weaken the reverse magnetic field, the magnetic stability of the magnetic steel 5 is enhanced, and the risk of demagnetization caused by the magnetic field generated by the current is reduced. This structural design optimizes the magnetic circuit, reduces the magnetic field loss in the magnetic circuit, and improves the efficiency and output power of the motor.

[0036] The above is only a preferred specific implementation method of the utility model, but the design concept of the utility model is not limited to this. Any technician familiar with the technical field who uses this concept to make non-substantial changes to the utility model within the technical scope disclosed by the utility model shall be deemed to infringe the protection scope of the utility model.

Claims

1. A rotor punching structure, characterized in that: A plurality of magnetic steel slots are arranged on the rotor punching sheet, wherein the magnetic steel slots are composed of a plurality of edge segments connected in sequence, and each edge segment is smoothly connected by an arc; Two groups of first grooves and two groups of second grooves are axially symmetrically arranged on the magnetic steel groove; the first grooves are arranged on the outer side of the magnetic steel groove, and the second grooves are arranged on the inner side of the magnetic steel groove; The first groove protrudes outward, and the first groove is arranged parallel to the outer side of the magnetic steel groove; the second groove protrudes inward, and is arranged in the opposite direction to the first groove.

2. A rotor punching structure according to claim 1, characterized in that: The first groove, the second groove and the edge section of the magnetic steel groove are connected by arc transition.

3. A rotor punching structure according to claim 1, characterized in that: Grooves are arranged at the four corners of the magnetic steel slot, and two groups of first grooves and two groups of second grooves are arranged at the upper and lower parts.

4. A rotor punching structure according to claim 1, characterized in that: A first groove and a second groove are arranged at any position of the outer side and the inner side of the magnetic steel groove.

5. A rotor punching structure according to claim 3 or 4, characterized in that: The number of grooves in a single group of first grooves is set at 1-3; the number of grooves in a single group of second grooves is set at 1-3.

6. A rotor punching structure according to claim 1, characterized in that: The length of the first groove is set to 1 / 30-1 / 15 of the length of the magnetic steel groove.

7. A rotor punching structure according to claim 1, characterized in that: The number of magnetic steel slots arranged on the rotor punching sheet is greater than or equal to 4.

8. A rotor punching structure according to claim 1, characterized in that: The magnetic steel slots are distributed in a straight line on the rotor punching sheets.

9. A motor rotor, characterized in that: The invention comprises a rotor punching structure as claimed in any one of claims 1 to 8.

10. A motor, characterized in that: Comprising the motor rotor as described in claim 9.

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