Magnetic field regulation and control type high-speed permanent magnet motor based on temperature-sensitive magnetic field regulation coil

Abstract

The magnetic field regulation and control type high-speed permanent magnet motor comprises a stator and a rotor, the rotor is located on the inner side of the stator, and the stator comprises a stator yoke part, stator teeth and auxiliary teeth, and the stator teeth and the auxiliary teeth are arranged in the circumferential direction of the stator yoke part at intervals; the auxiliary teeth are provided with temperature-sensitive magnetic adjusting coils, and the two sides of each temperature-sensitive magnetic adjusting coil are close to an inner side rotor area and an outer side stator area of the motor respectively. The power-on state of the temperature-sensitive magnetic field adjusting coil is determined according to the resistance difference value of the inner side and the outer side of the temperature-sensitive magnetic field adjusting coil, and the magnetic field in the motor can be dynamically adjusted by controlling the power-on state of the temperature-sensitive magnetic field adjusting coil so that a heat source of the motor can be migrated to an outer side stator area from an inner side rotor area. According to the invention, the temperature-sensitive magnetic field adjusting coil is utilized to carry out adaptive adjustment on the magnetic field in the motor by taking the heat transfer direction as a criterion, and temperature rise distribution in the motor is dynamically optimized, so that the problem that the torque increasing capability of the motor is limited due to hot-spot temperature rise is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of motor magnetic regulation, and in particular to a magnetic field regulating high-speed permanent magnet motor based on a temperature-sensitive magnetic regulation coil. Background Art

[0002] Permanent magnet synchronous motors (PMSMs) are categorized as rotor-type and stator-type permanent magnet synchronous motors (PMSMs), depending on the location of their permanent magnets. The rotor-type PMSM, a high-performance, highly reliable AC motor, outputs stable torque by coupling its internal stator armature magnetic field with the rotating magnetic field of the rotor's permanent magnet excitation. Due to its low manufacturing cost, high power factor, and high torque density, the rotor-type PMSM has become an important alternative to traditional electrically excited motors. High-speed PMSMs, owing to their high efficiency, high power density, and excellent dynamic performance, have found widespread application in aerospace, industrial automation, and other fields. However, during high-speed operation, eddy current losses in the permanent magnets increase due to the high harmonics of the air gap flux density, leading to elevated hot spot temperatures and the risk of permanent magnet demagnetization, severely limiting further improvements in the motor's output torque capability. Therefore, reducing rotor temperature and minimizing the risk of permanent magnet demagnetization has become a pressing issue.

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

[0004] In response to the deficiencies in the prior art, the present invention provides a magnetic field-regulated high-speed permanent magnet motor based on temperature-sensitive magnetic tuning coils. The temperature-sensitive magnetic tuning coils are used to adaptively adjust the magnetic field inside the motor based on the direction of heat transfer, dynamically optimizing the temperature rise distribution inside the motor, thereby solving the problem of limiting the motor's torque boost capability due to the increase in hot spot temperatures.

[0005] The present invention provides a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic tuning coil, comprising a stator and a rotor, wherein the rotor is located inside the stator, and the stator comprises a stator yoke and stator teeth and auxiliary teeth arranged at intervals along the circumference of the stator yoke; the auxiliary teeth are provided with a temperature-sensitive magnetic tuning coil, and the inner and outer sides of the temperature-sensitive magnetic tuning coil are respectively close to the inner rotor region and the outer stator region of the motor; the power-on state of the temperature-sensitive magnetic tuning coil is determined according to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil, and by controlling the power-on state of the temperature-sensitive magnetic tuning coil, the magnetic field inside the motor can be dynamically adjusted so that the heat source of the motor is transferred from the inner rotor region to the outer stator region.

[0006] Optionally, the power-on state of the temperature-sensitive magnetic tuning coil is determined according to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil, including: Determining the temperature difference between the inner rotor region and the outer stator region based on the resistance difference between the two sides of the temperature-sensitive magnetic tuning coil; When the temperature of the inner rotor area of ​​the motor is higher than the temperature of the outer stator area, a magnetic field current is passed into the temperature-sensitive magnetic field regulating coil to generate an auxiliary magnetic field to regulate the magnetic field inside the motor; 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 in the motor has reached the expected level, and no magnetic tuning current is passed into the temperature-sensitive magnetic tuning coil.

[0007] Optionally, the resistance value of the temperature-sensitive magnetic tuning coil decreases as the temperature increases.

[0008] Optionally, determining the temperature difference between the inner rotor region and the outer stator region according to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil includes: When the outer resistance of the temperature-sensitive magnetic tuning coil is greater than the inner resistance, the temperature of the inner rotor area of ​​the motor is higher than the temperature of the outer stator area; When the outer resistance of the temperature-sensitive magnetic tuning 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.

[0009] Optionally, during the process of passing the magnetic tuning current through the temperature-sensitive magnetic tuning coil, the current amplitude of the magnetic tuning current is proportional to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil.

[0010] Optionally, the temperature-sensitive magnetic tuning coils are arranged on the auxiliary teeth along the radial direction, circumferential direction or axial direction of the motor.

[0011] Optionally, when the temperature-sensitive magnetic tuning coils are arranged radially on the auxiliary teeth, the arrangement spacing of the temperature-sensitive magnetic tuning coils is negatively correlated with the temperature difference gradient between the rotor and the stator under preset working conditions.

[0012] Optionally, the temperature-sensitive magnetic tuning coil is radially wound on the auxiliary teeth.

[0013] Optionally, the temperature-sensitive magnetic tuning coils are arranged in a centralized or distributed manner.

[0014] Compared with the prior art, the present invention has the following beneficial effects: the inner and outer sides of the temperature-sensitive magnetic tuning coil in the present invention are respectively close to the inner rotor area with poor heat dissipation and the outer stator area with good heat dissipation of the motor, and the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil can reflect the heat transfer direction inside the motor and the temperature rise change inside the motor in real time. The present invention determines the power-on state of the temperature-sensitive magnetic tuning coil by the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil, and can adaptively control the power-on state of the temperature-sensitive magnetic tuning coil according to the temperature rise change inside the motor, thereby dynamically adjusting the magnetic field inside the motor. Through such an adaptive control method, the present invention can migrate the heat source of the motor from the inner rotor area with poor heat dissipation to the outer stator area with good heat dissipation, thereby adjusting the temperature rise distribution inside the motor, reducing the risk of permanent magnet demagnetization and effectively suppressing the temperature rise of hot spots inside the motor, removing the restriction of thermal constraints on the motor torque, and ensuring that the motor always operates in a high efficiency range. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more apparent; Figure 1 A main cross-sectional view of the axis and stator teeth of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic tuning coil provided in an embodiment of the present invention; Figure 2 A cross-sectional view perpendicular to the axis of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic tuning coil provided in an embodiment of the present invention; Figure 3 This is a magnetic flux density cloud diagram obtained by simulation of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic flux-regulating coil according to an embodiment of the present invention before applying magnetic flux-regulating current; Figure 4 This is a magnetic flux density cloud diagram obtained by simulation of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic flux coil according to an embodiment of the present invention after applying a magnetic flux modulation current; Figure 5 The cogging torque waveforms under different magnetic tuning currents obtained by simulation of a magnetic field-controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic tuning coil according to an embodiment of the present invention are shown; Figure 6 The load torque waveforms under different magnetic tuning currents obtained by simulating a magnetic field-controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic tuning coil according to an embodiment of the present invention are as follows; Figure 7 The air gap magnetic flux harmonic distribution diagram under different magnetic tuning currents obtained by simulation of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic tuning coil according to an embodiment of the present invention; Figure 8This is a stator temperature rise distribution diagram obtained by simulation of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to an embodiment of the present invention before applying magnetic field regulating current; Figure 9 This is a stator temperature rise distribution diagram obtained by simulation of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to an embodiment of the present invention after applying a magnetic field regulating current; Figure 10 This is a rotor temperature rise distribution diagram obtained by simulation of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to an embodiment of the present invention before applying magnetic field regulating current; Figure 11 This is a rotor temperature rise distribution diagram obtained by simulation of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to an embodiment of the present invention after applying a magnetic field regulating current; Figure 12 This is a temperature rise distribution diagram of a temperature-sensitive magnetic field regulating coil before applying magnetic field regulating current, obtained by simulation of a magnetic field regulating high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to an embodiment of the present invention; Figure 13 This is a temperature rise distribution diagram of a temperature-sensitive magnetic field regulating coil after applying a magnetic field regulating current, obtained from a simulation of a high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to an embodiment of the present invention; Figure 14 This is a temperature rise distribution diagram of the armature winding before applying the magnetic field modulation current, obtained by simulation of a magnetic field regulated high-speed permanent magnet motor based on a temperature-sensitive magnetic field modulation coil according to an embodiment of the present invention; Figure 15 This is a temperature rise distribution diagram of the armature winding after applying a magnetic field modulation current, obtained by simulation of a magnetic field regulated high-speed permanent magnet motor based on a temperature-sensitive magnetic field modulation coil according to an embodiment of the present invention; Figure 16 This is a permanent magnet temperature rise distribution diagram obtained by simulation of a magnetic field controlled high-speed permanent magnet motor based on a temperature-sensitive magnetic field regulating coil according to an embodiment of the present invention before applying a magnetic field regulating current; Figure 17 This is a diagram showing the temperature rise distribution of the permanent magnet after applying the magnetic field modulation current, obtained by simulation of a magnetic field regulated high-speed permanent magnet motor based on a temperature-sensitive magnetic field modulation coil according to an embodiment of the present invention.

[0016] Description of the accompanying drawings: 1. Stator; 101. Stator yoke; 102. Stator teeth; 103. Auxiliary teeth; 104. Armature winding; 2. Rotor; 201. Shaft; 202. Rotor core; 203. Permanent magnet; 204. Rotor salient pole; 3. Temperature sensitive magnetic adjustment coil; 4. Casing. DETAILED DESCRIPTION

[0017] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0018] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0019] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0020] Combine Figure 1 and Figure 2 This embodiment discloses a high-speed permanent magnet motor with a magnetic field control structure based on temperature-sensitive magnetic flux-regulating coils. 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. Each stator tooth 102 and auxiliary tooth 103 is alternately connected to the stator yoke 101. The rotor 2 is rotatable relative to the stator 1 and includes a shaft 201, a rotor core 202, permanent magnets 203, and rotor salient poles 204.

[0021] Combine Figure 1 and Figure 2The motor also includes a temperature-sensitive magnetic tuning coil 3 disposed on the auxiliary teeth 103. The inner and outer sides of the temperature-sensitive magnetic tuning coil 3 are respectively located near the inner rotor 2 and outer stator 1 regions of the motor. The temperature-sensitive magnetic tuning coil 3 is used to monitor the local temperature rise distribution within the motor. The difference in resistivity at different locations on the temperature-sensitive magnetic tuning coil 3 can be used to determine the direction of heat transfer within the motor.

[0022] Specifically, the power-on state of the temperature-sensitive magnetic tuning coil 3 in this embodiment is determined according to the resistance difference on both sides of the temperature-sensitive magnetic tuning coil 3. By controlling the power-on state of the temperature-sensitive magnetic tuning 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 transferred from the inner rotor 2 area to the outer stator 1 area, thereby adjusting the temperature rise distribution inside the motor, forming a magnetothermal coupling adjustment mechanism of "temperature rise change-temperature sensitive coil perception-adaptive magnetic tuning-temperature field distribution reconstruction", which solves the problem of limiting the motor torque improvement capability due to the increase in hot spot temperature.

[0023] In this embodiment, the rotor 2 is located inside the stator 1. The inner rotor 2 area is the motor's heat-difficult-to-dissipate region, while the outer stator 1 area is the motor's heat-dissipating region. The temperature-sensitive magnetic tuning coils 3 are radially arranged on the auxiliary teeth 103 of the stator 1. (In other specific embodiments, the temperature-sensitive magnetic tuning coils 3 can also be arranged circumferentially or axially of the motor, with the arrangement direction of the temperature-sensitive magnetic tuning coils 3 consistent with the heat dissipation path of the motor's temperature rise.) The radial spacing of the temperature-sensitive magnetic tuning coils 3 on the auxiliary teeth 103 is negatively correlated with the temperature gradient between the rotor 2 and stator 1 under preset operating conditions.

[0024] To illustrate with reference to the specific working principle, the resistance difference between the radial inner and outer sides of the temperature-sensitive magnetic tuning coil 3 can reflect the direction and intensity of the radial heat flow inside the motor in real time. When the outer resistance of the temperature-sensitive magnetic tuning coil 3 is greater than the inner resistance (the temperature of the inner rotor 2 area is higher than the temperature of the outer stator 1 area), a magnetic tuning current is passed through the temperature-sensitive magnetic tuning coil 3. The magnetic tuning current generates an auxiliary magnetic field in the temperature-sensitive magnetic tuning coil 3, changing the local magnetic circuit saturation state and magnetic flux distribution, thereby directing heat sources such as iron loss from the inner rotor 2 area with poor heat dissipation to the outer stator 1 area with good heat dissipation, actively optimizing the internal temperature rise distribution and reducing the risk of demagnetization of the permanent magnet 203. During the power-on process of the magnetic tuning current passing through the temperature-sensitive magnetic tuning coil 3, the current amplitude of the magnetic tuning current is proportional to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil 3. When the outer resistance of the temperature-sensitive magnetic tuning coil 3 is less than or equal to the inner resistance (the temperature of the inner rotor 2 region is less than or equal to the temperature of the outer stator 1 region), the motor has achieved the desired optimal temperature rise distribution. No magnetic tuning current is passed through the temperature-sensitive magnetic tuning coil 3, and magnetic tuning is stopped. This adaptive control process of the temperature-sensitive magnetic tuning coil 3 effectively suppresses the temperature rise of hot spots within the motor, removing thermal constraints on motor torque and enabling the motor to continuously output high torque in its high-efficiency range. Understandably, this embodiment employs a strategy of increasing the temperature rise of the stator 1 (located on the outer side, with better heat dissipation conditions) to reduce the temperature rise of the rotor 2, fully leveraging the advantages of the stator 1's heat dissipation, thereby balancing the overall temperature rise of the motor and improving motor performance.

[0025] In summary, this embodiment addresses the high-torque density requirements of applications such as robotic joints and electric vehicle drives, providing a simple structure for a permanent magnet synchronous motor with high efficiency, high permanent magnet utilization, and high output torque. Furthermore, this embodiment utilizes permanent magnets 203 for excitation, eliminating the need for field windings and resulting in high efficiency and power density.

[0026] 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 that of the stator teeth 102, thereby providing space for the placement of the armature winding 104 and the temperature-sensitive magnetic tuning coil 3 while meeting the magnetic field control requirements. The temperature coefficient of the temperature-sensitive magnetic tuning coil 3 ranges from -0.5% / °C to -5% / °C to ensure the accuracy and agility of dynamic magnetic tuning. The number of turns of each temperature-sensitive magnetic 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 capacity and efficiency of the motor. The cross-sectional shape of each auxiliary tooth 103 in the cross section perpendicular to the axis 201 is "I"-shaped or "7"-shaped. The armature winding 104 adopts centralized or distributed winding. As a preferred embodiment, the armature winding 104 adopts 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 working under load, thereby improving the motor operation efficiency.

[0027] The rotor 2 includes a plurality of permanent magnets 203, which are fixedly mounted on the outer periphery of the rotor core 202. Specifically, Figure 1 and Figure 2 As shown, the N pole of the rotor 2 adopts a permanent magnet 203, and the S poles are all replaced by iron core poles. The characteristic of the magnetic conductive core converging magnetic lines of force to form magnetic poles is utilized to form an alternating pole structure, so that the permanent magnet utilization rate of the motor is effectively improved. The magnetic steel thickness and pole arc coefficient of the permanent magnet pole can be increased while the amount of permanent magnet 203 remains unchanged. At the same time, this structure can avoid the magnetic saturation problem of the stator 1 core, make the magnetic field distribution more uniform, and significantly improve the torque output capacity of the motor.

[0028] The stator yoke 101 and rotor core 202 are made of stacked slotted silicon steel sheets. The permanent magnets 203 are either neodymium iron boron permanent magnets or ferrite permanent magnets. The motor also includes a housing 4, which is fixedly mounted on the outer periphery of the stator yoke 101. Furthermore, to enhance motor stability, a sleeve is fixed to the outer side of the rotor 2 to protect the permanent magnets 203 from centrifugal forces.

[0029] 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 based on motor principles for simulation analysis of the motor's electromagnetic performance and temperature field. Specifically, the finite element simulation model is used to simulate and analyze electromagnetic properties such as the motor's magnetic flux distribution, no-load back EMF, cogging torque, air gap magnetic flux harmonic distribution, load torque, and losses, and calculates the motor's efficiency at rated operating conditions.

[0030] Table 1 Comparison of motor losses and electromagnetic performance parameters

[0031] Combined with Table 1, after applying the magnetic tuning current, the eddy current loss of the permanent magnet 203 during steady-state operation of the motor is reduced from 34.7 W to 18.4 W, and the iron loss of the rotor 2 is reduced from 17.5 W to 9.5 W. This is beneficial to reducing the temperature rise of the rotor 2, removing the restriction on the motor's torque boosting capability, and reducing the risk of demagnetization of the permanent magnet 203. In addition, after applying the magnetic tuning current, the rotor 2 iron loss and the eddy current loss of the permanent magnet 203 during steady-state operation of the motor are reduced, while the stator 1 iron loss increases. The increase in the stator 1 iron loss and the magnetic tuning copper loss is approximately equal to the decrease in the rotor 2 iron loss and the eddy current loss of the permanent magnet 203. From the perspective of loss, the feasibility of the method of guiding the heat source from the high-temperature inner rotor 2 region to the low-temperature outer stator 1 region of the motor is verified. In addition, after applying the magnetic tuning current, the motor efficiency increases from 85.8% before magnetic tuning to 87.8%, thereby controlling the motor to operate in a high-efficiency range.

[0032] Furthermore, the comparison Figure 3 and Figure 4 It can be seen that after applying the magnetic modulation current, the magnetic saturation degree of the stator teeth 102 of the motor is reduced, which is conducive to obtaining higher output torque and lower torque ripple; Figure 5 As shown in Table 1, after applying the magnetic modulation current, the cogging torque is reduced, which improves the stability and control accuracy of the motor operation. Figure 6 After applying the magnetic modulation current, the motor output torque can be increased from 6.30Nm to 7.91Nm, and the output power can be increased from 2805.2W to 2870.9W, which improves the torque output capacity of the motor; Figure 7 As shown in the figure, after the magnetic modulation current is applied, the amplitude of the main working harmonic (5th harmonic) of the air gap magnetic flux increases, and the amplitude of the non-working harmonic decreases, which is beneficial to improving the torque quality of the motor.

[0033] During the simulation process, the losses of each part of the motor can be obtained by analyzing and calculating the motor losses. The losses of each part of the motor can be converted into the unit loss density of the corresponding part to obtain the temperature field distribution inside the motor of this embodiment when there is no DC magnetic modulation and when the magnetic modulation current is 6A. Figure 8 and Figure 9 It can be seen that after the magnetic modulation current is applied, the maximum temperature of stator 1 increases from 73.43℃ to 76.19℃. Figure 10 and Figure 11 It can be seen that after applying the magnetic modulation current, the maximum temperature of rotor 2 drops from 78.00℃ to 68.32℃, removing the limitation on the motor torque boosting capability. Figure 12 and Figure 13It can be seen that after applying the magnetic tuning current, the temperature rise distribution of the temperature-sensitive magnetic tuning coil 3 changes from 69.18℃~71.43℃ to 73.37℃~75.29℃, and the temperature difference between the inside and outside of the temperature-sensitive magnetic tuning coil 3 decreases 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 met the expectations and the magnetic tuning can be stopped. Figure 14 and Figure 15 It can be seen that after the magnetic modulation current is applied, the maximum temperature of the armature winding 104 increases from 73.17°C to 76.11°C. Figure 16 and Figure 17 It can be seen that after applying the magnetic modulation current, the maximum temperature of permanent magnet 203 drops from 78.00°C to 68.32°C, reducing the risk of demagnetization of permanent magnet 203. In summary, after applying the magnetic modulation current, the losses in the motor stator 1 increase, and the temperature rises; while the losses in the rotor 2 decrease, and the temperature drops. The heat source shifts from the inner rotor 2 region with low thermal conductivity to the outer stator 1 region with high thermal conductivity, optimizing the temperature rise distribution of the entire machine and aligning with the electromagnetic simulation analysis results.

[0034] The present invention provides a concept and method for a magnetic field-controlled high-speed permanent magnet motor based on temperature-sensitive magnetic tuning coils. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention. These improvements and variations should also be regarded as within the scope of protection of the present invention.

Claims

1. A magnetic field control type high-speed permanent magnet motor based on a temperature-sensitive magnetic tuning 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 at intervals along the circumference of the stator yoke (101); characterized in that: A temperature-sensitive magnetic adjustment coil (3) is provided on the auxiliary tooth (103), and the inner and outer sides of the temperature-sensitive magnetic adjustment coil (3) are respectively close to the inner rotor (2) area and the outer stator (1) area of ​​the motor; the power-on 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 power-on 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 is transferred from the inner rotor (2) area to the outer stator (1) area.

2. The magnetic field controlled high-speed permanent magnet motor based on temperature-sensitive magnetic tuning coil according to claim 1, characterized in that: The power-on 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), including: Determining the temperature difference between the inner rotor (2) region and the outer stator (1) region based on the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil (3); 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 in the motor has reached the expected level, and no magnetic adjustment current is passed into the temperature-sensitive magnetic adjustment coil (3).

3. The magnetic field controlled high-speed permanent magnet motor based on temperature-sensitive magnetic tuning coil according to claim 2, characterized in that: The resistance value of the temperature-sensitive magnetic tuning coil (3) decreases as the temperature increases.

4. The magnetic field controlled high-speed permanent magnet motor based on temperature-sensitive magnetic tuning coils according to claim 3 is characterized in that: Determining the temperature difference between the inner rotor (2) region and the outer stator (1) region based on the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil (3) includes: When the outer resistance of the temperature-sensitive magnetic tuning 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 tuning 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.

5. The magnetic field controlled high-speed permanent magnet motor based on temperature-sensitive magnetic tuning coils according to claim 2, characterized in that: During the power-on process of the magnetic tuning current flowing into the temperature-sensitive magnetic tuning coil (3), the current amplitude of the magnetic tuning current is proportional to the resistance difference between the inner and outer sides of the temperature-sensitive magnetic tuning coil (3).

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

7. The magnetic field controlled high-speed permanent magnet motor based on temperature-sensitive magnetic tuning coils according to claim 6, characterized in that: When the temperature-sensitive magnetic adjustment coils (3) are arranged radially on the auxiliary teeth (103), the arrangement spacing of the temperature-sensitive magnetic adjustment coils (3) is negatively correlated with the temperature difference gradient between the rotor (2) and the stator (1) under a preset working condition.

8. The magnetic field controlled high-speed permanent magnet motor based on temperature-sensitive magnetic tuning coils according to claim 7, characterized in that: The temperature-sensitive magnetic tuning coil (3) is radially wound on the auxiliary teeth (103).

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

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