Variable flux memory motor adopting consequent pole double-layer staggered permanent magnet structure

Abstract

The invention discloses a variable flux memory motor adopting a consequent-pole double-layer staggered permanent magnet structure. Belongs to the field of motor design and manufacturing. Each layer of permanent magnet in the variable flux memory motor adopts a high coercive force (HCF) permanent magnet and a low coercive force (LCF) permanent magnet, the HCF and the LCF in each layer of permanent magnet form a parallel magnetic circuit, and the HCF and the LCF between the two layers of permanent magnets are arranged in a staggered manner to form a series magnetic circuit, so that the double-layer U-shaped staggered permanent magnet structure can have the advantages of series connection and parallel connection of the two permanent magnets; and meanwhile, good load magnetic stabilization capability and a wide magnetic adjustment range are achieved. In addition, the consequent pole permanent magnet design can effectively reduce the magnetic circuit magnetic resistance and improve the LCF magnetizing and demagnetizing effect.

Description

Technical Field

[0001] The present invention belongs to the field of motor design and manufacturing, and in particular relates to a variable flux memory motor adopting an alternating pole double-layer staggered permanent magnet structure. Background Art

[0002] With the rapid development of new energy vehicles, permanent magnet synchronous motors (PMSMs) play a vital role in vehicle powertrains. In the past, these motors typically employed a single series or parallel permanent magnet configuration to meet power requirements. However, the series or parallel configurations of traditional PMSMs have limitations. Series configurations can be limited by a narrow magnetic adjustment range and require larger magnetizing and demagnetizing currents, while parallel configurations can suffer from poor load magnetic stability, susceptibility to demagnetization, and low torque capability. These challenges have become increasingly prominent in the rapidly developing new energy vehicle market, necessitating more innovative solutions.

[0003] While existing hybrid structures combine the advantages of series and parallel structures, aiming to overcome their respective shortcomings and maintain relatively high efficiency under varying load conditions, improving motor performance, the motor's air gap flux density is relatively high in field weakening conditions, limiting the motor's magnetic field adjustment range.

[0004] In order to further improve the performance of the motor and adapt to the ever-changing market demand, the present invention proposes a variable flux memory motor using an alternating pole double-layer staggered permanent magnet structure. Summary of the Invention

[0005] The present invention proposes a variable flux memory motor with an alternating pole double-layer staggered permanent magnet structure to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above-mentioned objectives, the present invention provides a variable flux memory motor adopting an alternating pole double-layer staggered permanent magnet structure, comprising a stator, a rotor, a rotor permanent magnet and an armature winding, wherein the armature winding is arranged in the stator slot, the rotor is embedded with a rotor permanent magnet, and the rotor permanent magnet includes a high coercive force permanent magnet and a low coercive force permanent magnet.

[0007] Optionally, the high-coercivity permanent magnets and the low-coercivity permanent magnets in each layer of permanent magnets are arranged in parallel to form a parallel magnetic circuit.

[0008] Optionally, high-coercivity permanent magnets and low-coercivity permanent magnets are alternately arranged along the axial direction between the two layers of permanent magnets to form a series magnetic circuit.

[0009] Optionally, the rotor adopts an alternating pole structure, wherein the permanent magnets are all of the same polarity, the iron core and the permanent magnets are arranged alternately, and the iron core replaces the permanent magnet of one polarity.

[0010] Optionally, the rotor permanent magnet includes a first permanent magnet layer and a second permanent magnet layer arranged along the axial direction, the central axis of the low coercive force permanent magnet in the first permanent magnet layer coincides with the d-axis, and the central axis of the high coercive force permanent magnet in the second permanent magnet layer coincides with the d-axis.

[0011] Optionally, the rotor permanent magnets are arranged in a U shape to form a double-layer staggered structure.

[0012] Optionally, the magnetic flux generated by the high-coercive force permanent magnet forms a closed loop through the adjacent low-coercive force permanent magnet, so as to reduce the air gap magnetic flux density.

[0013] Compared with the prior art, the present invention has the following advantages and technical effects:

[0014] 1. The double-layer staggered permanent magnet structure of the present invention can simultaneously achieve good load magnetic stabilization capability, reduce the demagnetization risk of the permanent magnet, and broaden the magnetic adjustment range.

[0015] 2. The present invention rationally designs the magnetic flux path so that the magnetic flux generated by the HCF permanent magnet can form a closed loop through the LCF permanent magnet, thereby reducing the magnetic flux density in the air gap and the magnetic flux density under demagnetization conditions, further improving the magnetic adjustment capability.

[0016] 3. The alternating pole structure of the present invention can greatly reduce the amount of permanent magnets used, lower the magnetic circuit reluctance, enhance the LCF charging and demagnetization effect, and increase the magnetic modulation multiple. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0018] Figure 1 A schematic structural diagram of a variable flux memory motor according to an embodiment of the present invention;

[0019] Figure 2 Schematic diagram of the structure of a single permanent magnet pole according to an embodiment of the present invention;

[0020] Figure 3 This is a diagram showing the distribution of magnetic lines of force in a magnetized state of a motor according to an embodiment of the present invention;

[0021] Figure 4 This is a diagram showing the distribution of magnetic lines of force in a demagnetized state of a motor according to an embodiment of the present invention;

[0022] Figure 5 This is a curve diagram of radial air gap magnetic flux density in the motor under the charging and demagnetizing states according to an embodiment of the present invention;

[0023] In the figure: 1. stator; 2. rotor; 3. rotor permanent magnet; 3.1. high coercive force permanent magnet; 3.2. low coercive force permanent magnet; 4. armature winding. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0026] Example 1

[0027] like Figure 1 As shown, this embodiment provides a variable flux memory motor using an alternating pole double-layer staggered permanent magnet structure, comprising:

[0028] Stator 1 , rotor 2 , rotor permanent magnet 3 and armature winding 4 , armature winding 4 is placed in the slot of stator 1 , and rotor permanent magnet 3 is embedded in the rotor 2 .

[0029] The rotor permanent magnets 3 include high-coercivity permanent magnets 3.1 and low-coercivity permanent magnets 3.2. The magnetic flux generated by the high-coercivity permanent magnets 3.1 passes through the adjacent low-coercivity permanent magnets 3.2 to form a closed loop, thereby reducing the air gap magnetic flux density.

[0030] Further, if Figure 2 The high-coercivity permanent magnets and low-coercivity permanent magnets in each permanent magnet layer form a parallel magnetic circuit; the HCF permanent magnets and LCF permanent magnets are placed in a cross-shaped manner in the two permanent magnet layers to form a series magnetic circuit.

[0031] Furthermore, in the first permanent magnet layer, low-coercivity permanent magnets are located along the d-axis, while in the second permanent magnet layer, high-coercivity permanent magnets are located along the d-axis. The d-axis is the main magnetic path direction of the rotor permanent magnet magnetic field, i.e., the central symmetry line of the permanent magnet poles (N or S poles).

[0032] Furthermore, each layer of permanent magnets is arranged in a U-shape, with HCF and LCF permanent magnets of varying sizes interlaced to form numerous small units connected in series and parallel. This combines the advantages of both series and parallel permanent magnet configurations, ensuring both excellent load-stabilizing magnetic field capability and a wide magnetic field adjustment range. Furthermore, the alternating-pole design effectively reduces the use of permanent magnets, lowers the magnetic resistance of the magnetic circuit, and further extends the magnetic field adjustment range.

[0033] Furthermore, the rotor employs an alternating-pole structure, wherein the permanent magnets all have the same polarity. The iron core and the permanent magnets are arranged alternately, with the iron core replacing the permanent magnets of one polarity. This embodiment employs an alternating-pole, double-layer staggered permanent magnet structure, replacing the permanent magnets of one polarity with the iron core. This not only reduces the number of permanent magnets used, but also effectively reduces the magnetic resistance of the magnetic circuit, resulting in a more significant LCF magnetization effect.

[0034] The distribution of magnetic lines of force in different states of variable flux memory motor is as follows Figure 3-Figure 4 shown.

[0035] Figure 5 This is a curve of radial air gap magnetic flux density in the motor charging and demagnetizing state. The horizontal axis is the current angle and the vertical axis is the electromagnetic density.

[0036] The operating principle of the variable flux memory motor in this embodiment is as follows: in the hybrid magnetic circuit, each layer of permanent magnets contains many parallel magnetic circuits, so the magnetic flux generated by the magnetizing current can pass directly through the LCF permanent magnets, thereby achieving a wider magnetizing range and reducing the risk of accidental demagnetization. The second layer of permanent magnets, with permanent magnets of different coercive forces from the first layer, forms a series magnetic circuit with the first layer. The magnetic flux of the HCF permanent magnets can pass through the LCF permanent magnets, improving the load's magnetic stabilization capability and providing the motor with a greater torque density. The magnetic flux generated by the HCF permanent magnets forms a closed loop through the LCF permanent magnets, reducing the magnetic flux density in the air gap and improving the magnetic stabilization capability in the weak magnetic field state. The alternating pole structure used in the motor can significantly reduce the amount of permanent magnets used and reduce the magnetic circuit reluctance, thereby changing the magnetic field distribution of the motor, making the charging and demagnetization effects of the LCF permanent magnets more pronounced and increasing the magnetizing range.

[0037] The above are merely preferred embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A variable flux memory motor with an alternating pole double-layer staggered permanent magnet structure, characterized in that: The invention comprises a stator (1), a rotor (2), a rotor permanent magnet (3) and an armature winding (4); the armature winding (4) is arranged in a slot of the stator (1); the rotor permanent magnet (3) is embedded in the rotor (2); and the rotor permanent magnet (3) comprises a high-coercive force permanent magnet (3.1) and a low-coercive force permanent magnet (3.2).

2. The variable flux memory motor according to claim 1, characterized in that: The high-coercive force permanent magnets (3.1) and the low-coercive force permanent magnets (3.2) in each layer of permanent magnets are arranged in parallel to form a parallel magnetic circuit.

3. The variable flux memory motor according to claim 1, characterized in that: Between the two layers of permanent magnets, high-coercivity permanent magnets (3.1) and low-coercivity permanent magnets (3.2) are staggered along the axial direction to form a series magnetic circuit.

4. The variable flux memory motor according to claim 1, characterized in that: The rotor (2) adopts an alternating pole structure, wherein the permanent magnets are all of the same polarity, the iron cores and the permanent magnets are arranged alternately, and the iron cores replace the permanent magnets of one polarity.

5. The variable flux memory motor according to claim 1, characterized in that: The rotor permanent magnet (3) comprises a first permanent magnet layer and a second permanent magnet layer arranged in the axial direction, wherein the central axis of the low-coercive force permanent magnet (3.2) in the first permanent magnet layer coincides with the d-axis, and the central axis of the high-coercive force permanent magnet (3.1) in the second permanent magnet layer coincides with the d-axis.

6. The variable flux memory motor according to claim 1, characterized in that: The rotor permanent magnets (3) are arranged in a U shape to form a double-layer staggered structure.

7. The variable flux memory motor according to claim 1, characterized in that: The magnetic flux generated by the high-coercive force permanent magnet (3.1) forms a closed loop through the adjacent low-coercive force permanent magnet (3.2), which is used to reduce the air gap magnetic flux density.

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