A high-speed permanent magnet motor with magnetic field control based on a temperature-sensitive magnetic coil

Abstract

This invention discloses a high-speed permanent magnet motor with magnetic field control based on a temperature-sensitive magnetic field regulating coil, comprising a stator and a rotor. The rotor is located inside the stator. The stator includes a stator yoke and stator teeth and auxiliary teeth arranged circumferentially along the stator yoke. A temperature-sensitive magnetic field regulating coil is mounted on each auxiliary tooth, with its two sides close to the inner rotor region and the outer stator region of the motor, respectively. The energizing state of the temperature-sensitive magnetic field regulating coil is determined based on the resistance difference between its inner and outer sides. By controlling the energizing state of the coil, the magnetic field inside the motor can be dynamically adjusted to transfer the heat source from the inner rotor region to the outer stator region. This invention utilizes a temperature-sensitive magnetic field regulating coil to adaptively adjust the magnetic field inside the motor based on the heat transfer direction, dynamically optimizing the temperature rise distribution within the motor, thereby solving the problem of limited motor torque increase capability due to hot spot temperature rise.

Description

Technical Field

[0001] This invention relates to the field of motor magnetic adjustment technology, and in particular to a high-speed permanent magnet motor with magnetic field control based on a temperature-sensitive magnetic adjustment coil. Background Technology

[0002] Permanent magnet synchronous motors (PMSMs) are classified into rotor PMSMs and stator PMSMs based on the mounting position of their permanent magnets. Rotor PMSMs, on the other hand, output stable torque through coupling between the stator armature magnetic field and the rotating magnetic field of the rotor's permanent magnet excitation, making them a high-performance, high-reliability AC motor. Due to their advantages such as low manufacturing cost, high power factor, and high torque density, rotor PMSMs have become an important alternative to traditional electrically excited motors. High-speed PMSMs, with their high efficiency, high power density, and excellent dynamic performance, are widely used in aerospace, industrial automation, and other fields. However, during high-speed operation, eddy current losses in the permanent magnets increase due to the influence of higher harmonics in the air gap magnetic flux density, leading to increased hot spot temperatures and thus increasing the risk of permanent magnet demagnetization, severely limiting further improvements in the motor's output torque capability. Therefore, reducing rotor temperature and mitigating the risk of permanent magnet demagnetization has become a pressing issue.

[0003] Traditional magnetization methods typically use fixed or variable resistors to adjust the magnetization current, but these methods have some limitations. Fixed resistors cannot dynamically adjust the magnetization current according to the motor's operating status and actual temperature rise distribution, while variable resistors require complex mechanical structures or electronic control circuits, increasing the system's complexity and cost. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a high-speed permanent magnet motor with magnetic field control based on a temperature-sensitive magnetic adjustment coil. The temperature-sensitive magnetic adjustment coil adaptively adjusts the magnetic field inside the motor based on the heat transfer direction, dynamically optimizing the temperature rise distribution inside the motor, thereby solving the problem of the motor's torque enhancement capability being limited by the temperature rise of hot spots.

[0005] This invention provides a high-speed permanent magnet motor with magnetic field control based on a temperature-sensitive magnetic coil, comprising a stator and a rotor, the rotor being located inside the stator. The stator includes a stator yoke and stator teeth and auxiliary teeth arranged circumferentially along the stator yoke. A temperature-sensitive magnetic coil is mounted on each auxiliary tooth, with its inner and outer sides close to the inner rotor region and the outer stator region of the motor, respectively. The energizing state of the temperature-sensitive magnetic coil is determined based on the resistance difference between its inner and outer sides. By controlling the energizing state of the temperature-sensitive magnetic coil, the magnetic field within the motor can be dynamically adjusted to transfer the heat source of the motor from the inner rotor region to the outer stator region.

[0006] Optionally, the energizing state of the temperature-sensitive magnetizing coil is determined based on the resistance difference between the inner and outer sides of the temperature-sensitive magnetizing coil, including:

[0007] The temperature difference between the inner rotor region and the outer stator region is determined based on the resistance difference on both sides of the temperature-sensitive tuning coil.

[0008] When the temperature of the inner rotor region of the motor is higher than that of the outer stator region, a magnetic adjustment current is passed into the temperature-sensitive magnetic adjustment coil to generate an auxiliary magnetic field to adjust the magnetic field inside the motor.

[0009] When the temperature of the inner rotor region of the motor is not higher than that of the outer stator region, the temperature rise distribution inside the motor has reached the expected level, and no regulating current is passed through the temperature-sensitive regulating coil.

[0010] Optionally, the resistance of the temperature-sensitive magnetic coil decreases as the temperature increases.

[0011] Optionally, determining the temperature difference between the inner rotor region and the outer stator region based on the resistance difference between the inner and outer sides of the temperature-sensitive tuning coil includes:

[0012] When the resistance of the outer side of the temperature-sensitive magnetic coil is greater than the resistance of the inner side, the temperature of the inner rotor region of the motor is higher than the temperature of the outer stator region.

[0013] When the outer resistance of the temperature-sensitive magnetic coil is not greater than the inner resistance, the temperature of the inner rotor region of the motor is not higher than the temperature of the outer stator region.

[0014] Optionally, during the energizing process of the temperature-sensitive magnetic adjustment coil, the amplitude of the magnetic adjustment current is proportional to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic adjustment coil.

[0015] Optionally, the temperature-sensitive magnetic adjustment coil is arranged on the auxiliary teeth along the radial, circumferential, or axial direction of the motor.

[0016] Optionally, when the temperature-sensitive magnetic adjustment coils are arranged radially on the auxiliary teeth, the arrangement spacing of the temperature-sensitive magnetic adjustment coils is negatively correlated with the temperature difference gradient between the rotor and stator under preset operating conditions.

[0017] Optionally, the temperature-sensitive magnetic coil is wound radially around the auxiliary tooth.

[0018] Optionally, the temperature-sensitive magnetic adjustment coil adopts a centralized or distributed coil arrangement.

[0019] Compared to existing technologies, this invention offers the following advantages: In this invention, the inner and outer sides of the temperature-sensitive magnetic adjustment coil are located near the poorly cooled inner rotor region and the well-cooled outer stator region of the motor, respectively. The resistance difference between the inner and outer sides of the temperature-sensitive magnetic adjustment coil can reflect the direction of heat transfer and temperature rise changes within the motor in real time. This invention determines the energizing state of the temperature-sensitive magnetic adjustment coil based on the resistance difference between its inner and outer sides, and can adaptively control the energizing state of the coil according to changes in the motor's internal temperature rise, thereby dynamically adjusting the magnetic field within the motor. This adaptive control method allows the heat source of the motor to migrate from the poorly cooled inner rotor region to the well-cooled outer stator region, thereby adjusting the temperature rise distribution within the motor, reducing the risk of permanent magnet demagnetization, effectively suppressing hot spot temperature rise within the motor, removing the thermal constraint's limitation on motor torque, and ensuring that the motor always operates within a high-efficiency range. Attached Figure Description

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0021] Figure 1 This is a front sectional view of the axis and stator teeth of a magnetic field-controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic coil, provided as an embodiment of the present invention.

[0022] Figure 2 A cross-sectional view perpendicular to the axis of a high-speed permanent magnet motor based on a temperature-sensitive magnetic adjustment coil and a magnetic field-controlled motor, provided as an embodiment of the present invention.

[0023] Figure 3 The magnetic density cloud diagram obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive magnetic adjustment coil and a magnetic field control type before the application of the magnetic adjustment current is given in an embodiment of the present invention.

[0024] Figure 4 The magnetic density cloud map obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive magnetic adjustment coil and a magnetic field-controlled motor after applying a magnetic adjustment current is given in an embodiment of the present invention.

[0025] Figure 5 The cogging torque waveforms under different tuning currents obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive tuning coil are shown in this embodiment of the invention.

[0026] Figure 6 The following is a simulation diagram of the load torque waveform under different tuning currents obtained for an embodiment of the present invention: a high-speed permanent magnet motor based on a temperature-sensitive tuning coil and a magnetic field-controlled motor.

[0027] Figure 7The air gap magnetic flux density harmonic distribution diagram under different tuning currents is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive tuning coil, as presented in an embodiment of the present invention.

[0028] Figure 8 The stator temperature rise distribution diagram before applying the tuning current is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive tuning coil and a magnetic field-controlled motor, as provided in an embodiment of the present invention.

[0029] Figure 9 The stator temperature rise distribution diagram after applying the tuning current is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive tuning coil and a magnetic field-controlled motor, as provided in an embodiment of the present invention.

[0030] Figure 10 The rotor temperature rise distribution diagram before applying the tuning current is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive tuning coil, as provided in an embodiment of the present invention.

[0031] Figure 11 The rotor temperature rise distribution diagram after applying the tuning current is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive tuning coil and a magnetic field-controlled motor, as provided in an embodiment of the present invention.

[0032] Figure 12 The temperature rise distribution of the temperature-sensitive magnetizing coil before applying the magnetizing current is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive magnetizing coil and an embodiment of the present invention.

[0033] Figure 13 The temperature rise distribution of the temperature-sensitive magnetizing coil after applying the magnetizing current is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive magnetizing coil according to an embodiment of the present invention.

[0034] Figure 14 The armature winding temperature rise distribution diagram before applying the tuning current is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive tuning coil, as provided in an embodiment of the present invention.

[0035] Figure 15 The armature winding temperature rise distribution diagram after applying the magnetic adjustment current is obtained from the simulation of a high-speed permanent magnet motor based on a temperature-sensitive magnetic adjustment coil, which is an embodiment of the present invention.

[0036] Figure 16 The simulation results of a high-speed permanent magnet motor based on a temperature-sensitive magnetic adjustment coil and a magnetic field-controlled permanent magnet motor are shown in the figure below, which is a temperature rise distribution of the permanent magnet before the application of the magnetic adjustment current.

[0037] Figure 17 The temperature rise distribution of the permanent magnet after applying the adjusting current is obtained from the simulation of a magnetic field-controlled high-speed permanent magnet motor based on a temperature-sensitive adjusting coil, as provided in an embodiment of the present invention.

[0038] The accompanying labeling is as follows:

[0039] 1. Stator; 101. Stator yoke; 102. Stator teeth; 103. Auxiliary teeth; 104. Armature winding;

[0040] 2. Rotor; 201. Shaft; 202. Rotor core; 203. Permanent magnet; 204. Rotor salient pole;

[0041] 3. Temperature-sensitive magnetizing coil;

[0042] 4. Casing. Detailed Implementation

[0043] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0044] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0045] To make the purpose, technical solution, and advantages of this invention patent clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0046] Combination Figure 1 and Figure 2This embodiment discloses a high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil. The motor includes a stator 1 and a rotor 2. The stator 1 includes a stator yoke 101 and a plurality of stator teeth 102 and auxiliary teeth 103 arranged circumferentially along the stator yoke 101, with each stator tooth 102 and auxiliary tooth 103 alternately connected to the stator yoke 101. The rotor 2 is rotatable relative to the stator 1, and the rotor 2 includes a shaft 201, a rotor core 202, a permanent magnet 203, and a rotor salient pole 204.

[0047] Combination Figure 1 and Figure 2 The motor also includes a temperature-sensitive magnetic adjustment coil 3 disposed on the auxiliary gear 103. The inner and outer sides of the temperature-sensitive magnetic adjustment coil 3 are respectively close to the inner rotor 2 region and the outer stator 1 region of the motor. The temperature-sensitive magnetic adjustment coil 3 is used to monitor the local temperature rise distribution inside the motor, and the direction of heat transfer inside the motor can be determined by the resistivity difference at different positions of the temperature-sensitive magnetic adjustment coil 3.

[0048] Specifically, in this embodiment, the energizing state of the temperature-sensitive magnetic adjustment coil 3 is determined based on the resistance difference between the two sides of the temperature-sensitive magnetic adjustment coil 3. By controlling the energizing state of the temperature-sensitive magnetic adjustment coil 3, the magnetic field inside the motor can be dynamically adjusted according to the temperature rise change inside the motor, so that the heat source of the motor is moved from the inner rotor 2 region to the outer stator 1 region, thereby adjusting the temperature rise distribution inside the motor and forming a magnetothermal coupling adjustment mechanism of "temperature rise change - temperature-sensitive coil sensing - adaptive magnetic adjustment - temperature field distribution reconstruction", which solves the problem of limiting the motor torque increase capability due to the temperature rise of hot spots.

[0049] In this embodiment, the rotor 2 is located inside the stator 1. The inner rotor 2 area is the area where heat dissipation is difficult for the motor, while the outer stator 1 area is the area where heat dissipation is easy for the motor. The temperature-sensitive magnetic adjustment coil 3 is arranged radially on the auxiliary teeth 103 of the stator 1 (in some other specific embodiments, the temperature-sensitive magnetic adjustment coil 3 can also be arranged along the circumference or axial direction of the motor, and the arrangement direction of the temperature-sensitive magnetic adjustment coil 3 is consistent with the heat dissipation path of the motor temperature rise). The arrangement spacing of the temperature-sensitive magnetic adjustment coil 3 when it is arranged radially on the auxiliary teeth 103 is negatively correlated with the temperature difference gradient between the rotor 2 and the stator 1 under the preset operating conditions.

[0050] To illustrate the specific working principle, the resistance difference between the inner and outer radial sides of the temperature-sensitive magnetic adjustment coil 3 can reflect the direction and intensity of radial heat flow inside the motor in real time. When the resistance of the outer side of the temperature-sensitive magnetic adjustment coil 3 is greater than that of the inner side (the temperature of the inner rotor 2 region is higher than that of the outer stator 1 region), a magnetic adjustment current is passed through the temperature-sensitive magnetic adjustment coil 3. The magnetic adjustment current generates an auxiliary magnetic field in the temperature-sensitive magnetic adjustment coil 3, changing the local magnetic circuit saturation state and magnetic flux distribution, thereby guiding heat sources such as iron loss from the poorly heat-dissipated inner rotor 2 region to the well-heat-dissipated outer stator 1 region, actively optimizing the internal temperature rise distribution and reducing the risk of demagnetization of the permanent magnet 203. During the energization process of the magnetic adjustment current passing through the temperature-sensitive magnetic adjustment coil 3, the current amplitude of the magnetic adjustment current is directly proportional to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic adjustment coil 3. When the resistance of the outer side of the temperature-sensitive magnetic adjustment coil 3 is less than or equal to the resistance of the inner side (the temperature of the inner rotor 2 region is lower than or equal to the temperature of the outer stator 1 region), it indicates that the expected optimal temperature rise distribution has been reached within the motor. No magnetic adjustment current is then applied to the temperature-sensitive magnetic adjustment coil 3, and magnetic adjustment ceases. The aforementioned adaptive control process of the temperature-sensitive magnetic adjustment coil 3 effectively suppresses the temperature rise of hot spots within the motor, removes the thermal constraint limiting the motor torque, and allows the motor to continuously output high torque in the high-efficiency region. Understandably, this embodiment employs a strategy of increasing the temperature rise of stator 1 (located on the outer side with good heat dissipation) to reduce the temperature rise of rotor 2, fully utilizing the advantages of stator 1's heat dissipation conditions, thereby balancing the overall temperature rise of the motor and improving motor performance.

[0051] In summary, this embodiment addresses the high torque density applications such as robot joints and electric vehicle drives, providing a permanent magnet synchronous motor with high efficiency, high permanent magnet utilization, and large output torque, featuring a simple structure. Furthermore, the permanent magnet motor in this embodiment uses permanent magnets 203 for excitation, eliminating the need for excitation windings and achieving high efficiency and power density.

[0052] In some specific embodiments, stator slots are formed between adjacent stator teeth 102 and auxiliary teeth 103 of the stator 1, and the armature winding 104 is placed in the stator slots. The width of the auxiliary teeth 103 is smaller than the width of the stator teeth 102, thereby providing space for the placement of the armature winding 104 and the temperature-sensitive tuning coil 3 while meeting the magnetic field control requirements. The temperature coefficient of the temperature-sensitive tuning coil 3 is in the range of -0.5% / ℃ to -5% / ℃ to ensure the accuracy and agility of dynamic magnetic adjustment. The number of turns of each temperature-sensitive tuning coil 3 is smaller than the number of turns of the armature winding 104 wound on the stator teeth 102, thereby improving the torque output capability and efficiency of the motor. The cross-sectional shape of each auxiliary tooth 103 in the cross-section perpendicular to the shaft 201 is "I" shaped or "7" shaped. The armature winding 104 adopts a centralized or distributed winding. As a preferred embodiment, the armature winding 104 adopts a centralized winding, which can save end space, reduce processing and manufacturing difficulty and material cost, reduce motor copper loss, and help reduce the temperature rise of the motor when it is under load, thereby improving the motor operating efficiency.

[0053] The rotor 2 includes a plurality of permanent magnets 203, which are fixedly installed on the outer periphery of the rotor core 202. Specifically, as Figure 1 and Figure 2 As shown, the N pole of rotor 2 uses permanent magnet 203, and the S pole is completely replaced by iron core pole. By utilizing the characteristic of magnetic core to converge magnetic lines of force to form magnetic poles, an alternating pole structure is formed, which effectively improves the utilization rate of permanent magnet in the motor. Without changing the amount of permanent magnet 203, the thickness of permanent magnet steel and pole arc coefficient can be increased. At the same time, this structure can avoid the magnetic saturation problem of stator 1 iron core, making the magnetic field distribution more uniform and significantly improving the torque output capability of the motor.

[0054] The stator yoke 101 and the rotor core 202 are made of stacked coffered silicon steel sheets. The permanent magnet 203 is a neodymium iron boron permanent magnet or a ferrite permanent magnet. The motor also includes a housing 4, which is fixedly fitted around the outer periphery of the stator yoke 101. In addition, to improve the stability of motor operation, a fixed sleeve is provided on the outer side of the rotor 2 to protect the permanent magnet 203 from centrifugal force.

[0055] Further explanation is provided based on the simulation data of the motor in this embodiment. This embodiment establishes 2D and 3D finite element simulation models according to the motor principle for simulation analysis of the motor's electromagnetic performance and temperature field. Specifically, using the finite element simulation model, the electromagnetic performance of the motor, including magnetic flux density distribution, no-load back EMF, cogging torque, air gap magnetic flux density harmonic distribution, load torque, and losses, is simulated and analyzed, and the motor's efficiency under rated operating conditions is calculated.

[0056] Table 1 Comparison of Motor Losses and Electromagnetic Performance Parameters

[0057]

[0058] According to Table 1, after applying the adjusting current, the eddy current loss of permanent magnet 203 during steady-state operation of the motor decreased from 34.7W to 18.4W, and the iron loss of rotor 2 decreased from 17.5W to 9.5W. This helps to reduce the temperature rise of rotor 2, remove the limitation on the motor's torque enhancement capability, and reduce the risk of demagnetization of permanent magnet 203. Furthermore, after applying the adjusting current, the iron loss of rotor 2 and the eddy current loss of permanent magnet 203 during steady-state operation of the motor decreased, while the iron loss of stator 1 increased. The increase in the iron loss of stator 1 and the adjusting copper loss is approximately equal to the decrease in the iron loss of rotor 2 and the eddy current loss of permanent magnet 203. From the perspective of loss, this verifies the feasibility of the method of guiding the heat source from the high-temperature inner region of rotor 2 to the low-temperature outer region of stator 1. In addition, after applying the adjusting current, the motor efficiency increased from 85.8% before adjusting the current to 87.8%, thereby controlling the motor to operate in the high-efficiency range.

[0059] Furthermore, in comparison Figure 3 and Figure 4 It can be seen that after applying the adjusting current, the magnetic saturation of the stator teeth 102 of the motor is reduced, which is beneficial to obtaining higher output torque and lower torque ripple; such as Figure 5 As shown, applying the adjusting current reduces the cogging torque, improving the stability and control accuracy of the motor operation; combined with Table 1 and Figure 6 After applying the magnetic adjustment current, the motor's output torque can increase from 6.30 Nm to 7.91 Nm, and the output power can increase from 2805.2 W to 2870.9 W, thus improving the motor's torque output capability; Figure 7 As shown, after applying the adjusting current, the amplitude of the main working harmonic (5th harmonic) of the air gap magnetic flux density increases, while the amplitude of the non-working harmonic decreases, which is beneficial to improving the torque quality of the motor.

[0060] During the simulation, the losses of each part of the motor can be obtained through analysis and calculation of motor losses. These losses are then converted into unit loss densities for the corresponding parts, yielding the internal temperature field distribution of the motor in this embodiment under conditions of no DC magnetization and a magnetization current of 6A. (Comparison) Figure 8 and Figure 9 It can be seen that after applying the magnetizing current, the highest temperature of stator 1 increased from 73.43℃ to 76.19℃. (Comparison) Figure 10 and Figure 11 It can be seen that after applying the magnetic adjustment current, the highest temperature of rotor 2 dropped from 78.00℃ to 68.32℃, thus removing the limitation on the motor's torque enhancement capability. (Comparison) Figure 12 and Figure 13After applying the adjusting current, the temperature rise distribution of the temperature-sensitive adjusting coil 3 changed from 69.18℃~71.43℃ to 73.37℃~75.29℃, and the temperature difference between the inner and outer sides of the temperature-sensitive adjusting coil 3 decreased from 2.25℃ to 1.92℃. When the temperature difference approaches zero or reaches the preset lower limit, it means that the temperature rise distribution has reached the expected level, and adjusting the magnetization can be stopped. (Comparison) Figure 14 and Figure 15 It can be seen that after applying the magnetizing current, the highest temperature of the armature winding 104 increased from 73.17℃ to 76.11℃. (Comparison) Figure 16 and Figure 17 It can be seen that after applying the adjusting current, the highest temperature of permanent magnet 203 decreased from 78.00℃ to 68.32℃, reducing the risk of demagnetization of permanent magnet 203. In summary, after applying the adjusting current, the loss of the stator 1 part of the motor increased, and the temperature rose; the loss of the rotor 2 part decreased, and the temperature dropped. The heat source migrated from the inner rotor 2 region with low thermal conductivity to the outer stator 1 region with high thermal conductivity, optimizing the overall temperature rise distribution, which is consistent with the electromagnetic simulation analysis results.

[0061] This invention provides a concept and method for a magnetic field-controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic coil. The above description is only a preferred embodiment of this invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention.

Claims

1. A high-speed permanent magnet motor based on a temperature-sensitive magnetic field-controlled coil, comprising a stator (1) and a rotor (2), wherein the rotor (2) is located inside the stator (1), and the stator (1) comprises a stator yoke (101) and stator teeth (102) and auxiliary teeth (103) arranged circumferentially along the stator yoke (101); characterized in that, The auxiliary tooth (103) is provided with a temperature-sensitive magnetic adjustment coil (3). The inner and outer sides of the temperature-sensitive magnetic adjustment coil (3) are close to the inner rotor (2) region and the outer stator (1) region of the motor, respectively. The energizing state of the temperature-sensitive magnetic adjustment coil (3) is determined according to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic adjustment coil (3). By controlling the energizing state of the temperature-sensitive magnetic adjustment coil (3), the magnetic field inside the motor can be dynamically adjusted so that the heat source of the motor can be moved from the inner rotor (2) region to the outer stator (1) region. The energizing state of the temperature-sensitive magnetic coil (3) is determined based on the resistance difference between the inner and outer sides of the temperature-sensitive magnetic coil (3), including: Based on the resistance difference between the inner and outer sides of the temperature-sensitive magnetic adjustment coil (3), the temperature difference between the inner rotor (2) region and the outer stator (1) region is determined. When the temperature of the inner rotor (2) region of the motor is higher than the temperature of the outer stator (1) region, a magnetic adjustment current is passed into the temperature-sensitive magnetic adjustment coil (3) to generate an auxiliary magnetic field to adjust the magnetic field inside the motor. When the temperature of the inner rotor (2) region of the motor is not higher than that of the outer stator (1) region, the temperature rise distribution inside the motor has reached the expected level, and no magnetic adjustment current is passed into the temperature-sensitive magnetic adjustment coil (3). The resistance of the temperature-sensitive magnetic coil (3) decreases as the temperature increases; Based on the resistance difference between the inner and outer sides of the temperature-sensitive tuning coil (3), the temperature difference between the inner rotor (2) region and the outer stator (1) region is determined, including: When the outer resistance of the temperature-sensitive magnetic coil (3) is greater than the inner resistance, the temperature of the inner rotor (2) region of the motor is higher than the temperature of the outer stator (1) region. When the outer resistance of the temperature-sensitive magnetic coil (3) is not greater than the inner resistance, the temperature of the inner rotor (2) region of the motor is not higher than the temperature of the outer stator (1) region.

2. The high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to claim 1, characterized in that, During the energizing process of the temperature-sensitive magnetic adjustment coil (3), the current amplitude of the magnetic adjustment current is proportional to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic adjustment coil (3).

3. The high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to claim 1, characterized in that, The temperature-sensitive magnetic adjustment coil (3) is arranged on the auxiliary teeth (103) along the radial, circumferential or axial direction of the motor.

4. The high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to claim 3, characterized in that, When the temperature-sensitive magnetic adjustment coil (3) is arranged radially on the auxiliary tooth (103), the arrangement spacing of the temperature-sensitive magnetic adjustment coil (3) is negatively correlated with the temperature difference gradient between the rotor (2) and the stator (1) under the preset working conditions.

5. The high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to claim 4, characterized in that, The temperature-sensitive magnetic coil (3) is wound radially around the auxiliary tooth (103).

6. The high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to claim 1, characterized in that, The temperature-sensitive magnetic adjustment coil (3) adopts a centralized or distributed coil arrangement.

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