Adaptive heat dissipation cylinder type magnetic transmission system for electric motor

Abstract

The application relates to the technical field of magnetic coupling transmission, and discloses a self-adaptive heat dissipation cylinder type magnetic transmission system for a motor, which comprises a magnetic transmission module and a coupling control module; the magnetic transmission module comprises a conductor rotor, a permanent magnet rotor, a motor flange and an output flange; the conductor rotor is fixedly connected with the motor flange, and the permanent magnet rotor is fixedly connected with the output flange; the conductor rotor and the permanent magnet rotor are coaxially nested and installed, and an axial gap is reserved; the coupling control module is used for collecting operation parameters of the magnetic transmission module, and identifying whether the magnetic transmission module is in a heat accumulation state based on the operation parameters; when the magnetic transmission module is in the heat accumulation state, the coupling control module adjusts the axial gap to assist the magnetic transmission module in self-adaptive heat dissipation. The application can realize self-adaptive heat dissipation of the magnetic transmission system, reduce daily maintenance, and be suitable for various complex industrial working conditions.

Description

Technical Field

[0001] This application relates to the technical field of magnetic coupling transmission, and specifically to an adaptive heat sink type magnetic transmission system for electric motors. Background Technology

[0002] Existing electric motor drive systems can incorporate a magnetic coupling transmission mechanism between the motor and the load to transmit torque non-contactly, reducing wear and vibration caused by mechanical contact. This magnetic coupling transmission mechanism typically includes a conductor rotor driven by the motor and a permanent magnet rotor connected to the load. As the conductor rotor rotates, a speed difference is created between it and the permanent magnet rotor, inducing eddy currents within the conductor. The magnetic fields corresponding to these eddy currents interact with the permanent magnet's magnetic field, generating a magnetically coupled torque that drives the load. During torque transmission, eddy current losses caused by the speed difference are converted into heat. For cylindrical coaxial nested structures, the space between the rotor wall, magnet mounting area, end cover, and transmission clearance is relatively compact, making it difficult to dissipate internal heat promptly. Continuous heat accumulation affects the magnetic coupling torque and the output speed on the load side, reduces motor transmission efficiency, and causes attenuation of the permanent magnet's magnetic properties.

[0003] Existing magnetic coupling transmission mechanisms mostly employ fixed transmission clearances and are equipped with ventilation slots, air guide structures, or external water cooling systems. When the motor starts, accelerates, or the load torque changes, the slip between the input and output ends also changes, leading to variations in the torque transmission state and heat generation of the mechanism. Fixed transmission clearances and fixed heat dissipation structures make it difficult to simultaneously meet the transmission and heat dissipation requirements under different load conditions.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the overall background of this application and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] This application addresses the shortcomings of existing magnetic drive devices, such as poor heat dissipation, high temperature rise, and complex and easily leaking water-cooled structures. It provides an adaptive heat dissipation cylinder-type magnetic drive system for electric motors, which enables forced convection to dissipate internal heat, reduces the overall temperature of the machine, and significantly reduces the risk of permanent magnet demagnetization, thus adapting to various complex industrial conditions.

[0006] To solve the above-mentioned technical problems, this application provides the following technical solution:

[0007] An adaptive heat dissipation cylindrical magnetic drive system for electric motors includes a magnetic drive module and a coupling control module.

[0008] The magnetic drive module includes a conductor rotor, a permanent magnet rotor, a motor flange, and an output flange; wherein the conductor rotor is fixedly connected to the motor flange, and the permanent magnet rotor is fixedly connected to the output flange; the conductor rotor and the permanent magnet rotor are installed in a coaxial nested manner, with axial clearance reserved.

[0009] The coupling control module is used to collect the operating parameters of the magnetic drive module and identify whether the magnetic drive module is in a state of heat accumulation based on the operating parameters. When the magnetic drive module is in a state of heat accumulation, the coupling control module assists the magnetic drive module in adaptive heat dissipation by adjusting the axial clearance.

[0010] As a preferred embodiment of the adaptive heat dissipation cylindrical magnetic drive system for an electric motor described in this application, the permanent magnet rotor includes a magnet, a magnetic cylinder, a magnetic cylinder cover, and a first cover plate; wherein:

[0011] The magnetic cylinder is used to carry and hold the magnet; the magnetic cylinder cover is used to seal the magnetic cylinder; the magnet consists of multiple permanent magnets;

[0012] The permanent magnets are arranged circumferentially inside the magnetic cylinder, and the magnetic poles of any two adjacent permanent magnets are opposite in direction.

[0013] The first cover plate is fixedly connected to the magnetic cylinder and the output flange respectively, and is provided with a first heat dissipation duct; the first heat dissipation duct includes a plurality of slots distributed circumferentially on the first cover plate.

[0014] As a preferred embodiment of the adaptive heat dissipation cylinder-type magnetic transmission system for electric motors described in this application, the conductor rotor includes an inner iron cylinder, an outer iron cylinder, a second cover plate, a first heat dissipation fin, and a second heat dissipation fin.

[0015] The first heat sink includes multiple air guide fins distributed on the inner wall of the inner iron cylinder; the second heat sink includes multiple air guide fins distributed on the outer wall of the outer iron cylinder.

[0016] The second cover plate is used to seal the inner and outer iron cylinders and is fixedly connected to the motor flange; the second cover plate is provided with a second heat dissipation duct and a third heat dissipation duct; the second heat dissipation duct and the third heat dissipation duct are respectively included in multiple slots distributed circumferentially on the second cover plate.

[0017] As a preferred embodiment of the adaptive heat dissipation cylindrical magnetic drive system for electric motors described in this application, the coupling control module includes a sensor unit; the sensor unit is used to collect operating parameters of the magnetic drive module; the operating parameters include input speed, output speed, first temperature, second temperature, and gap distance;

[0018] The first temperature represents the temperature of the conductor rotor; the second temperature represents the temperature of the permanent magnet rotor; the gap distance represents the axial length of the axial gap;

[0019] The sensor unit is configured with a uniform sampling period. At the beginning of each sampling period, each operating parameter is collected synchronously once.

[0020] As a preferred embodiment of the adaptive heat dissipation cylindrical magnetic drive system for electric motors described in this application, the coupling control module further includes a computing unit; the computing unit is configured with a heat accumulation identification strategy to identify whether the magnetic drive module is in a state of heat accumulation; the heat accumulation identification strategy specifically includes:

[0021] Set an observation window; the observation window includes the most recent W consecutive sampling periods; W is a positive integer;

[0022] Based on the operating parameters, the slip rate, master control temperature, and temperature rise rate within the observation window are calculated for each sampling period.

[0023] If the slip rate of each sampling period within the observation window is greater than the preset slip rate threshold, and the temperature rise rate is greater than the preset temperature rise rate threshold, or the second temperature of each sampling period within the observation window is greater than the preset second temperature threshold, then the magnetic drive module is in a state of heat accumulation.

[0024] As a preferred embodiment of the adaptive heat dissipation cylindrical magnetic drive system for electric motors described in this application, the heat accumulation identification strategy further includes a method for calculating the temperature rise rate and the slip ratio and main control temperature for any sampling period, specifically including:

[0025] For any sampling period, calculate the difference between the input speed and the output speed to obtain the speed difference; calculate the ratio of the speed difference to the input speed to obtain the slip ratio;

[0026] For any sampling period, the larger value between the first temperature and the second temperature is taken as the main control temperature;

[0027] The master temperature of the earliest sampling period within the observation window is marked as the first master temperature; the master temperature of the latest sampling period within the observation window is marked as the second master temperature; the difference between the second master temperature and the first master temperature is calculated and divided by the length of the observation window to obtain the temperature rise rate.

[0028] As a preferred embodiment of the adaptive heat dissipation cylinder-type magnetic drive system for electric motors described in this application, the coupling control module further includes a control unit and an execution unit; the control unit is configured with a gap control strategy for calculating the gap adjustment amount of the axial gap; the control unit generates an adjustment command based on the gap adjustment amount and sends it to the execution unit; the execution unit parses the adjustment command to obtain the gap adjustment amount, and adjusts the gap distance of the axial gap based on the gap adjustment amount, including driving the permanent magnet rotor to move axially along the rotation axis, such that after the permanent magnet rotor moves, the gap distance is reduced compared to before the permanent magnet rotor moves, and the reduction amount is equal to the gap adjustment amount.

[0029] As a preferred embodiment of the adaptive heat dissipation cylindrical magnetic drive system for electric motors described in this application, the gap control strategy includes:

[0030] Based on the slip ratio, the main control temperature, and the temperature rise rate, the slip deviation and the heat accumulation are calculated; the values ​​of the slip deviation and the heat accumulation are both in the range of 0 to 1.

[0031] Calculate the fuzzy membership degree of the slip deviation degree and the fuzzy membership degree of the heat accumulation degree respectively; the fuzzy membership degree of either slip deviation degree or heat accumulation degree includes a first membership degree, a second membership degree, and a third membership degree.

[0032] A reference adjustment strength is set; the reference adjustment strength includes a first adjustment strength, a second adjustment strength, and a third adjustment strength; the value of any one of the reference adjustment strengths is between 0 and 1;

[0033] Assign a correlation membership degree to each reference regulation strength, and determine the activation degree of each reference regulation strength based on the correlation membership degree; calculate the overall regulation strength based on the activation degree of each reference regulation strength.

[0034] The maximum gap adjustment amount is determined based on the gap distance; the product of the comprehensive adjustment intensity and the maximum gap adjustment amount is calculated as the gap adjustment amount.

[0035] As a preferred embodiment of the adaptive heat dissipation cylindrical magnetic drive system for electric motors described in this application, the calculation of slip deviation and heat accumulation specifically includes:

[0036] Calculate the mean slip rate for each sampling period within the observation window, and use it as the reference slip rate; calculate the mean second temperature for each sampling period within the observation window, and use it as the reference second temperature;

[0037] The slip deviation is assigned a value based on the reference slip rate; the slip deviation is positively correlated with the reference slip rate.

[0038] The temperature deviation is assigned a value based on the reference second temperature; the temperature deviation ranges from 0 to 1 and is positively correlated with the reference second temperature;

[0039] The temperature rise deviation is assigned a value based on the temperature rise rate; the temperature rise deviation ranges from 0 to 1 and is positively correlated with the temperature rise rate.

[0040] The larger of the temperature deviation and the temperature rise deviation is taken as the heat accumulation degree.

[0041] As a preferred embodiment of the adaptive heat sink magnetic drive system for electric motors described in this application, the activation degree of any reference adjustment intensity is determined by: marking the association membership degree of the reference adjustment intensity that is greater than 0 as its effective association membership degree; taking the minimum value among the effective association membership degrees as the activation degree of the reference adjustment intensity; if any reference adjustment intensity does not have an effective association membership degree, then its activation degree is recorded as 0.

[0042] The calculation of the overall regulation strength specifically includes: calculating the product of each reference regulation strength and its corresponding activation level as the trigger strength; and calculating the sum of the trigger strengths of all reference regulation strengths to obtain the overall regulation strength.

[0043] Compared with the prior art, the beneficial effects achieved by this application are as follows:

[0044] This application utilizes a cylindrical coaxial nested magnetic coupling structure to create a uniform and stable coupling air gap between the conductor rotor and the permanent magnet rotor. This improves the magnetic coupling torque density, reduces operational vibration and noise, and ensures smooth transmission. Simultaneously, the system forms a continuous heat dissipation path through heat sinks, cooling ducts, and air gap guiding structures, effectively removing heat generated by eddy currents and reducing the risk of long-term high-temperature operation and demagnetization of the permanent magnets, thereby extending the overall service life of the machine. This structure does not rely on external water circuits, water pumps, or sealed cooling components, avoiding potential leakage, maintenance, and installation space issues associated with water-cooled systems. This results in a more compact and adaptable overall structure, making it particularly suitable for outdoor, dusty, explosion-proof, water-scarce, or maintenance-limited industrial conditions.

[0045] This application comprehensively judges the slip state, temperature state and temperature rise trend of the magnetic coupling transmission system, and adaptively adjusts the coupling state according to the degree of heat accumulation, so as to maintain a reasonable dynamic balance between transmission efficiency, heat dissipation requirements and slip margin, thereby improving the stability of the equipment in continuous operation scenarios such as pumps, fans and conveyors. Attached Figure Description

[0046] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0047] Figure 1 An axial sectional view of the magnetic drive module provided in this application;

[0048] Figure 2 An axial sectional view of the permanent magnet rotor provided in this application;

[0049] Figure 3 A schematic diagram of the end face structure of the magnet and magnetic cylinder provided in this application;

[0050] Figure 4 An axial sectional view of the conductor rotor provided in this application;

[0051] Figure 5 This is a schematic diagram of the end face structure of the permanent magnet rotor provided in this application;

[0052] Figure 6 This is a schematic diagram of the end face structure of the conductor rotor provided in this application.

[0053] Explanation of reference numerals in the attached drawings: 1. Conductor rotor; 2. Permanent magnet rotor; 3. Motor flange; 4. Output flange; 5. Axial clearance; 11. Inner iron cylinder; 12. Outer iron cylinder; 13. Second cover plate; 14. First heat sink; 15. Second heat sink; 21. Magnet; 22. Magnetic cylinder; 23. Magnetic cylinder cover; 24. First cover plate; 51. First heat dissipation duct; 52. Second heat dissipation duct; 53. Third heat dissipation duct. Detailed Implementation

[0054] The technical solution of this application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments and specific features in the embodiments are detailed descriptions of the technical solution of this application, rather than limitations thereof. In the absence of conflict, the embodiments and technical features in the embodiments can be combined with each other.

[0055] This embodiment describes an adaptive heat dissipation cylindrical magnetic drive system for electric motors, which includes a magnetic drive module and a coupling control module.

[0056] Reference Figure 1The magnetic drive module includes a conductor rotor 1, a permanent magnet rotor 2, a motor flange 3, and an output flange 4; wherein the conductor rotor 1 is fixedly connected to the motor flange 3, and the permanent magnet rotor 2 is fixedly connected to the output flange 4; the conductor rotor 1 and the permanent magnet rotor 2 are installed in a coaxial nested manner, with an axial gap 5 reserved.

[0057] When the magnetic drive module is working, the motor flange 3 drives the conductor rotor 1 to rotate under the drive of the motor. The magnetic field of the permanent magnet rotor 2 acts on the conductor rotor 1, causing the conductor rotor 1 to generate eddy currents. The magnetic field formed by the eddy currents interacts with the magnetic field of the permanent magnet rotor 2, thereby generating a magnetic coupling torque. This magnetic coupling torque drives the permanent magnet rotor 2 and the output flange 4 fixedly connected to it to rotate, realizing the power transmission from the motor side to the load side. The output flange 4 is connected to the load through the output shaft, such as various industrial pumps, fans, conveyor drive systems, etc. In this embodiment, the conductor rotor 1 and the permanent magnet rotor 2 are installed in a coaxial nested manner. The two rotate around the same rotation axis without contact. That is, the center of the bottom surface of the inner iron cylinder 11, the outer iron cylinder 12 and the magnetic cylinder 22 are located on the same straight line, which is the rotation axis of the conductor rotor 1 and the permanent magnet rotor 2.

[0058] like Figure 2 As shown, the permanent magnet rotor 2 includes a magnet 21, a magnetic cylinder 22, a magnetic cylinder cover 23, and a first cover plate 24; wherein:

[0059] The magnetic cylinder 22 is used to support and fix the magnet 21; the magnetic cylinder cover 23 is used to seal the magnetic cylinder 22; the magnet 21 includes multiple permanent magnets;

[0060] The permanent magnets are arranged circumferentially inside the magnetic cylinder 22, and the magnetic poles of any two adjacent permanent magnets are opposite in direction.

[0061] According to such Figure 3 As shown in the arrangement, the permanent magnets can form a circumferentially alternating permanent magnet magnetic field, which causes the conductor rotor 1 to generate induced eddy currents during rotation, forming a circumferentially alternating induced magnetic field; the induced magnetic field and the permanent magnet magnetic field interact due to the slip, thereby generating a magnetic coupling torque to drive the permanent magnet rotor 2 to rotate. Figure 3 Each sector ring corresponds to a permanent magnet, and the N or S markings inside the sector ring indicate the magnetic poles of the permanent magnet.

[0062] The first cover plate 24 is fixedly connected to the magnetic cylinder 22 and the output flange 4 respectively, and is provided with a first heat dissipation duct 51; the first heat dissipation duct 51 includes a plurality of slots distributed circumferentially on the first cover plate 24.

[0063] like Figure 4 As shown, the conductor rotor 1 includes an inner iron cylinder 11, an outer iron cylinder 12, a second cover plate 13, a first heat sink 14, and a second heat sink 15;

[0064] After installation, the inner iron cylinder 11 is located radially inside the magnetic cylinder 22, and the outer iron cylinder 12 is located radially outside the magnetic cylinder 22; a first radial air gap is formed between the inner iron cylinder 11 and the magnetic cylinder 22; a second radial air gap is formed between the outer iron cylinder 12 and the magnetic cylinder 22.

[0065] In this embodiment, the first radial air gap, the second radial air gap, and the axial gap 5 together achieve the isolation between the conductor rotor 1 and the permanent magnet rotor 2, so that a non-contact power transmission is formed from the motor side to the load side.

[0066] The first heat sink 14 includes multiple air guide fins distributed on the inner wall of the inner iron cylinder 11; the second heat sink 15 includes multiple air guide fins distributed on the outer wall of the outer iron cylinder 12.

[0067] The second cover plate 13 is used to cover the inner iron cylinder 11 and the outer iron cylinder 12, and is fixedly connected to the motor flange 3; the second cover plate 13 is provided with a second heat dissipation air duct 52 and a third heat dissipation air duct 53; the second heat dissipation air duct 52 and the third heat dissipation air duct 53 respectively include a plurality of slots distributed circumferentially on the second cover plate 13.

[0068] like Figure 5 As shown, the first heat dissipation duct 51 includes a plurality of circumferentially distributed elongated oval slots; the first heat dissipation duct 51 communicates with the first radial air gap and can be used for convection between the first radial air gap and the outside environment; as shown Figure 6 As shown, the second heat dissipation duct 52 includes multiple circumferentially distributed fan-shaped annular slots, and the third heat dissipation duct 53 includes multiple circumferentially distributed arc-shaped elongated slots. The second heat dissipation duct 52 is connected to the internal cavity of the inner iron cylinder 11, and the third heat dissipation duct 53 is connected to the second radial air gap. Both can realize the convection between the inside of the magnetic drive module and the external environment, send hot air out of the device, and introduce cold air from the outside to achieve continuous heat dissipation.

[0069] like Figure 4 or Figure 6 As shown, the first heat sink 14 includes air guide fins installed on the inner wall of the inner iron cylinder 11; there is a cavity inside the inner iron cylinder 11. When the inner iron cylinder 11 generates a large amount of heat due to induced eddy currents, the air in the cavity plays a role in heat dissipation; the first heat sink 14 can increase the heat exchange area between the air and the inner iron cylinder 11 and improve the heat dissipation efficiency; in addition, when the inner iron cylinder 11 rotates at high speed, the air guide fins will drive the air in the cavity to rotate synchronously, generating an axial pumping effect, pushing the hot air in the cavity to flow to both ends of the cavity, and finally flowing out to the outside of the system through the first heat dissipation air duct 51, the second heat dissipation air duct 52 and the third heat dissipation air duct 53.

[0070] like Figure 4 or Figure 6As shown, the second heat sink 15 includes air guide fins mounted on the outer wall of the outer iron cylinder 12. When the outer iron cylinder 12 generates a large amount of heat due to induced eddy currents, the second heat sink 15 can increase the heat exchange area between the air and the outer iron cylinder 12 to improve heat dissipation efficiency. When the outer iron cylinder 12 rotates at high speed, the air guide fins drive the outside air to flow through the gaps between its fins, forming a directional flow to actively carry away heat.

[0071] The coupling control module is used to collect the operating parameters of the magnetic drive module and identify whether the magnetic drive module is in a state of heat accumulation based on the operating parameters. When the magnetic drive module is in a state of heat accumulation, the coupling control module assists the magnetic drive module in adaptive heat dissipation by adjusting the axial clearance 5.

[0072] The coupling control module includes a sensor unit; the sensor unit is used to collect the operating parameters of the magnetic drive module; the operating parameters include input speed, output speed, first temperature, second temperature, and gap distance;

[0073] The input speed represents the rotational speed of the conductor rotor 1, which can be acquired by a speed sensor installed on the output shaft of the motor or the motor flange 3; the output speed represents the rotational speed of the permanent magnet rotor 2, which can be acquired by a speed sensor installed on the output flange 4.

[0074] The first temperature represents the temperature of the conductor rotor 1; the second temperature represents the temperature of the permanent magnet rotor 2; the gap distance represents the axial length of the axial gap 5;

[0075] The sensor unit is configured with a uniform sampling period. At the beginning of each sampling period, each operating parameter is collected synchronously once.

[0076] Optionally, the temperature of the inner iron cylinder 11 or the outer iron cylinder 12 is measured using a non-contact infrared temperature sensor as the first temperature to characterize eddy current heating and heat dissipation. The temperature of the magnetic cylinder 22 is measured using a non-contact infrared temperature sensor as the second temperature to characterize the heating state of the permanent magnet. The sampling period can be set to 1 second to reflect changes in operating parameters such as input rotation speed and output rotation speed in a timely manner.

[0077] The coupling control module further includes a computing unit; the computing unit is configured with a heat accumulation identification strategy to identify whether the magnetic drive module is in a state of heat accumulation; the heat accumulation identification strategy specifically includes:

[0078] Set an observation window; the observation window includes the most recent W consecutive sampling periods; W is a positive integer;

[0079] Based on the operating parameters, the slip rate, master control temperature, and temperature rise rate within the observation window are calculated for each sampling period.

[0080] If the slip rate of each sampling period within the observation window is greater than the preset slip rate threshold, and the temperature rise rate is greater than the preset temperature rise rate threshold, or the second temperature of each sampling period within the observation window is greater than the preset second temperature threshold, then the magnetic drive module is in a state of heat accumulation.

[0081] The heat accumulation identification strategy also includes a method for calculating the temperature rise rate and the slip ratio and master control temperature for any sampling period, specifically including:

[0082] For any sampling period, calculate the difference between the input speed and the output speed to obtain the speed difference; calculate the ratio of the speed difference to the input speed to obtain the slip ratio;

[0083] The larger the slip ratio, the more obvious the relative slip between the conductor rotor 1 and the permanent magnet rotor 2, the higher the eddy current loss generated by the conductor rotor 1, and the greater the heat generation.

[0084] For any sampling period, the larger value between the first temperature and the second temperature is taken as the main control temperature;

[0085] The master temperature of the earliest sampling period within the observation window is marked as the first master temperature; the master temperature of the latest sampling period within the observation window is marked as the second master temperature; the difference between the second master temperature and the first master temperature is calculated and divided by the length of the observation window to obtain the temperature rise rate.

[0086] When the temperature rise rate is greater than 0, it indicates that the master control temperature is maintaining an upward trend; when the temperature rise rate is equal to 0, it indicates that the current heat generation and air cooling heat dissipation are basically balanced; when the temperature rise rate is less than 0, it indicates that the current air cooling heat dissipation capacity is sufficient to bring the master control temperature down. To reduce the impact of single-point temperature fluctuations, the average of the master control temperatures of the three earliest sampling periods within the observation window can be used as the first master control temperature, and the average of the master control temperatures of the three latest sampling periods within the observation window can be used as the second master control temperature.

[0087] Optionally, the slip rate threshold ranges from 5% to 8%, used to limit the slip rate to the point where it causes significant eddy current heating. As an optional example, the normal operating temperature of the permanent magnet rotor 2 described in this embodiment is less than 80°C, and the second temperature threshold can be set to 75°C, used to limit the permanent magnet rotor 2 to the high-temperature operating range. As an optional example, the temperature rise rate threshold is set to 0.5°C / min, used to limit the main control temperature to maintain an upward trend. Based on the above threshold settings and heat accumulation identification strategy, adaptive heat dissipation adjustment can be triggered when slip is significant and heat is accumulating, avoiding erroneous adjustment due to single temperature fluctuations or short-term speed differences.

[0088] Optionally, W is set to 20. When the sampling period is 1 second, the corresponding observation window covers a time range of 20 seconds, which can smooth short-term speed fluctuations and temperature measurement noise, while reflecting the temperature rise trend.

[0089] The coupling control module further includes a control unit and an execution unit; the control unit is configured with a clearance control strategy for calculating the clearance adjustment amount of the axial clearance 5; the control unit generates an adjustment command based on the clearance adjustment amount and sends it to the execution unit; the execution unit includes an electric lead screw, an axial sliding seat, and a bearing assembly mounted on the axial sliding seat; the output flange 4 is connected to the load via an output shaft, the output shaft is supported by the bearing assembly, and the axial sliding seat is connected to the electric lead screw; the execution unit parses the adjustment command to obtain the clearance adjustment amount, and the electric lead screw drives the axial sliding seat to move along the rotation axis; the axial sliding seat drives the output shaft, output flange 4, and permanent magnet rotor 2 to move synchronously along the rotation axis via the bearing assembly, so that the clearance distance of the axial clearance 5 after the permanent magnet rotor 2 moves is reduced compared to before the movement, and the reduction amount is equal to the clearance adjustment amount.

[0090] In one optional embodiment, the axial sliding seat is provided with a linear guide or guide post, the extension direction of which is consistent with the direction of the rotation axis. This restricts the circumferential rotation and radial deflection of the axial sliding seat, allowing it to move only along the direction of the rotation axis. The bearing assembly can be an angular contact ball bearing or a tapered roller bearing to withstand the radial load on the output shaft and the axial push-pull force generated during axial adjustment. This allows the axial displacement of the axial sliding seat to be transmitted to the output shaft while maintaining the rotation of the output shaft relative to the axial sliding seat, enabling the output shaft to move axially with the axial sliding seat. A coupling that allows axial movement is provided between the output flange 4 and the load to accommodate the axial displacement of the output shaft with the permanent magnet rotor 2 and to reduce the impact of this axial displacement on the connection state at the load end.

[0091] The gap control strategy includes:

[0092] Based on the slip ratio, the main control temperature, and the temperature rise rate, the slip deviation and the heat accumulation are calculated; the values ​​of the slip deviation and the heat accumulation are both in the range of 0 to 1.

[0093] The calculation of slip deviation and heat accumulation specifically includes:

[0094] Calculate the mean slip rate for each sampling period within the observation window, and use it as the reference slip rate; calculate the mean second temperature for each sampling period within the observation window, and use it as the reference second temperature;

[0095] The slip deviation is assigned a value based on the reference slip rate; the slip deviation is positively correlated with the reference slip rate.

[0096] The temperature deviation is assigned a value based on the reference second temperature; the temperature deviation ranges from 0 to 1 and is positively correlated with the reference second temperature;

[0097] The temperature rise deviation is assigned a value based on the temperature rise rate; the temperature rise deviation ranges from 0 to 1 and is positively correlated with the temperature rise rate.

[0098] The larger of the temperature deviation and the temperature rise deviation is taken as the heat accumulation degree.

[0099] Optionally, the formula for assigning a value to the slip deviation is as follows:

[0100] ;

[0101] in, Indicates the degree of slip deviation; Indicates the reference slip ratio; This represents the slip ratio threshold. Calculated based on the above formula. And the value range is truncated to 0 to 1, including: if If it is less than 0, then assign it the value 0. If the value is greater than 1, then assign it the value 1.

[0102] Optionally, the formula for assigning a value to the temperature deviation is as follows:

[0103] ;

[0104] in, Indicates the degree of temperature deviation; Indicates a reference second temperature; This indicates the second temperature threshold. The preset upper limit of the operating temperature is set to 80℃ in this embodiment. The calculation is based on the above formula. And the value range is truncated to 0 to 1.

[0105] Optionally, the formula for assigning a value to the temperature rise deviation is as follows:

[0106] ;

[0107] in, Indicates the degree of temperature rise deviation; Indicates the rate of temperature rise; This represents the temperature rise rate threshold. Calculated based on the above formula. And the value range is truncated to 0 to 1.

[0108] Calculate the fuzzy membership degree of the slip deviation degree and the fuzzy membership degree of the heat accumulation degree respectively; the fuzzy membership degree of either slip deviation degree or heat accumulation degree includes a first membership degree, a second membership degree, and a third membership degree.

[0109] In this embodiment, for slip deviation or heat accumulation, the first membership degree, second membership degree, and third membership degree respectively characterize the probability that the slip deviation or heat accumulation degree exhibits a slight anomaly, a moderate anomaly, and a severe anomaly. For example, the larger the first membership degree of slip deviation, the greater the probability that the slip deviation is in a slight anomaly; the larger the third membership degree of slip deviation, the greater the probability that the slip deviation is in a severe anomaly.

[0110] As an optional implementation, for slip deviation or heat accumulation, a left-shoulder trapezoidal membership function is used to calculate the first membership degree, a triangular membership function is used to calculate the second membership degree, and a right-shoulder trapezoidal membership function is used to calculate the third membership degree. Specifically, slip deviation or heat accumulation is marked as the target index. As the target index increases from 0 to 0.25, its first membership degree is 1, and its second and third membership degrees are 0. As the target index increases from 0.25 to 0.5, its first membership degree decreases linearly from 1 to 0, its second membership degree increases linearly from 0 to 1, and its third membership degree is 0. As the target index increases from 0.5 to 0.75, its first membership degree is 0, its second membership degree decreases linearly from 1 to 0, and its third membership degree increases linearly from 0 to 1. As the target index increases from 0.75 to 1, its first and second membership degrees are both 0, and its third membership degree is 1.

[0111] A reference adjustment strength is set; the reference adjustment strength includes a first adjustment strength, a second adjustment strength, and a third adjustment strength; the value of any one of the reference adjustment strengths is between 0 and 1;

[0112] Assign a correlation membership degree to each reference regulation strength, and determine the activation degree of each reference regulation strength based on the correlation membership degree; calculate the overall regulation strength based on the activation degree of each reference regulation strength.

[0113] In this embodiment, the first adjustment intensity corresponds to the adjustment intensity of the gap distance when the slip deviation or heat accumulation exhibits a slight abnormality; the second adjustment intensity corresponds to the adjustment intensity of the gap distance when the slip deviation or heat accumulation exhibits a moderate abnormality; and the third adjustment intensity corresponds to the adjustment intensity of the gap distance when the slip deviation or heat accumulation exhibits a severe abnormality. Accordingly, the association membership degree of the first adjustment intensity includes the first membership degree of both slip deviation and heat accumulation; the association membership degree of the second adjustment intensity includes the second membership degree of both slip deviation and heat accumulation; and the association membership degree of the third adjustment intensity includes the third membership degree of both slip deviation and heat accumulation. This application adaptively controls the adjustment intensity of the gap distance based on heat dissipation requirements; the higher the heat dissipation requirements, the higher the adjustment intensity. As an optional implementation, the first adjustment intensity is set to 0.25, the second membership degree is set to 0.55, and the third membership degree is set to 0.85.

[0114] Determining the activation of any reference regulation strength specifically includes: marking the association membership degree with reference regulation strength greater than 0 as its effective association membership degree; taking the minimum value among the effective association membership degrees as the activation of the reference regulation strength; if any reference regulation strength has no effective association membership degree, then its activation is recorded as 0.

[0115] The calculation of the overall regulation strength specifically includes: calculating the product of each reference regulation strength and its corresponding activation level as the trigger strength; and calculating the sum of the trigger strengths of all reference regulation strengths to obtain the overall regulation strength.

[0116] The maximum gap adjustment amount is determined based on the gap distance; the product of the comprehensive adjustment intensity and the maximum gap adjustment amount is calculated as the gap adjustment amount.

[0117] Optionally, a minimum gap distance is set, and the difference between the gap distance of the most recent sampling period and the minimum gap distance is calculated as the maximum gap adjustment amount. As an optional implementation, the minimum gap distance is set to 5 mm; further, the maximum gap distance is set to 18 mm to assist in limiting the movement, ensuring the magnetic drive module operates within a higher-efficiency coupling range. Thus, the gap control strategy allows for a larger adjustment of the axial gap 5 when the slip ratio is abnormally high and the heat accumulation is severe, limiting the gap distance to the range of 5 to 18 mm, thereby enhancing magnetic coupling, reducing eddy current heat loss, and avoiding excessive adjustment.

[0118] The temperature rise of the conductor rotor 1 is mainly related to the eddy current loss caused by the speed difference. The change of the axial clearance 5 will change the effective coupling degree between the conductor rotor 1 and the permanent magnet rotor 2; when the clearance distance of the axial clearance 5 decreases, the magnetic coupling strength increases, and under constant load or small load change conditions, the output speed increases accordingly, resulting in a decrease in slip ratio, thereby reducing eddy current loss and suppressing the heat source.

[0119] One of the core values ​​of a magnetic coupling drive system lies in its soft start and overload protection, which relies on a reasonable slip margin. If the axial clearance 5 is too small, the magnetic coupling strength will be too high, making the transmission nearly rigid. This makes it difficult to buffer torque impacts during motor startup, leading to motor starting current overload. Under overload conditions, slippage is difficult to relieve the load, weakening the flexible protection capability. Furthermore, the equipment's thermal accumulation has thermal inertia. If the clearance is too low, the slip margin will be insufficient, causing a sudden increase in slip rate even with small load fluctuations, triggering temperature rise shocks and exacerbating the risk of thermal accumulation. This application adjusts the clearance distance as needed based on the severity of thermal accumulation to limit it within a reasonable range and avoid system oscillations caused by over-adjustment.

[0120] Furthermore, in actual implementation, those skilled in the art can add other auxiliary devices based on actual needs to assist the electric lead screw pusher in driving the axial sliding seat to generate axial displacement. For example, optionally, by setting linear guides or guide columns to limit the circumferential rotation and radial deflection of the axial sliding seat, only the axial single degree of freedom is retained, ensuring that the axial sliding seat strictly moves along the rotation axis; optionally, a coupling that allows axial movement, such as a spline bushing, slider coupling, diaphragm coupling, etc., is added between the output flange 4 and the load to isolate the influence of the axial displacement of the output flange 4 on the load.

[0121] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of protection of this application, and these forms are all within the protection scope of this application.

Claims

1. An adaptive heat dissipation cylindrical magnetic drive system for electric motors, characterized in that: Includes a magnetic drive module and a coupling control module; The magnetic drive module includes a conductor rotor (1), a permanent magnet rotor (2), a motor flange (3), and an output flange (4); wherein the conductor rotor (1) is fixedly connected to the motor flange (3), and the permanent magnet rotor (2) is fixedly connected to the output flange (4); the conductor rotor (1) and the permanent magnet rotor (2) are installed in a coaxial nested manner, and an axial gap (5) is reserved. The coupling control module is used to collect the operating parameters of the magnetic drive module and identify whether the magnetic drive module is in a state of heat accumulation based on the operating parameters. When the magnetic drive module is in a state of heat accumulation, the coupling control module assists the magnetic drive module in adaptive heat dissipation by adjusting the axial clearance (5).

2. The adaptive heat dissipation cylindrical magnetic drive system for electric motors as described in claim 1, characterized in that: The permanent magnet rotor (2) includes a magnet (21), a magnetic cylinder (22), a magnetic cylinder cover (23), and a first cover plate (24); wherein: The magnetic cylinder (22) is used to carry and fix the magnet (21); the magnetic cylinder cover (23) is used to seal the magnetic cylinder (22); the magnet (21) includes multiple permanent magnets; The permanent magnets are arranged circumferentially inside the magnetic cylinder (22), and the magnetic poles of any two adjacent permanent magnets are opposite in direction; The first cover plate (24) is fixedly connected to the magnetic cylinder (22) and the output flange (4) respectively, and is provided with a first heat dissipation duct (51); the first heat dissipation duct (51) includes a plurality of slots distributed circumferentially on the first cover plate (24).

3. The adaptive heat dissipation cylindrical magnetic drive system for electric motors as described in claim 2, characterized in that: The conductor rotor (1) includes an inner iron cylinder (11), an outer iron cylinder (12), a second cover plate (13), a first heat sink (14), and a second heat sink (15). The first heat sink (14) includes multiple air guide fins distributed on the inner wall of the inner iron cylinder (11); the second heat sink (15) includes multiple air guide fins distributed on the outer wall of the outer iron cylinder (12); The second cover plate (13) is used to cover the inner iron cylinder (11) and the outer iron cylinder (12) and is fixedly connected to the motor flange (3); the second cover plate (13) is provided with a second heat dissipation duct (52) and a third heat dissipation duct (53); the second heat dissipation duct (52) and the third heat dissipation duct (53) are respectively included in a plurality of slots distributed circumferentially on the second cover plate (13).

4. The adaptive heat dissipation cylindrical magnetic drive system for electric motors as described in claim 3, characterized in that: The coupling control module includes a sensor unit; the sensor unit is used to collect the operating parameters of the magnetic drive module; the operating parameters include input speed, output speed, first temperature, second temperature, and gap distance; The first temperature represents the temperature of the conductor rotor (1); the second temperature represents the temperature of the permanent magnet rotor (2); the gap distance represents the axial length of the axial gap (5); The sensor unit is configured with a uniform sampling period. At the beginning of each sampling period, each operating parameter is collected synchronously once.

5. The adaptive heat dissipation cylindrical magnetic drive system for electric motors as described in claim 4, characterized in that: The coupling control module also includes a computing unit; the computing unit is configured with a heat accumulation identification strategy to identify whether the magnetic drive module is in a state of heat accumulation. The heat accumulation identification strategy specifically includes: Set an observation window; the observation window includes the most recent W consecutive sampling periods; W is a positive integer; Based on the operating parameters, the slip rate, master control temperature, and temperature rise rate within the observation window are calculated for each sampling period. If the slip rate of each sampling period within the observation window is greater than the preset slip rate threshold, and the temperature rise rate is greater than the preset temperature rise rate threshold, or the second temperature of each sampling period within the observation window is greater than the preset second temperature threshold, then the magnetic drive module is in a state of heat accumulation.

6. The adaptive heat dissipation cylindrical magnetic drive system for electric motors as described in claim 5, characterized in that: The heat accumulation identification strategy also includes a method for calculating the temperature rise rate and the slip ratio and master control temperature for any sampling period, specifically including: For any sampling period, calculate the difference between the input speed and the output speed to obtain the speed difference; calculate the ratio of the speed difference to the input speed to obtain the slip ratio; For any sampling period, the larger value between the first temperature and the second temperature is taken as the main control temperature; The master temperature of the earliest sampling period within the observation window is marked as the first master temperature; the master temperature of the latest sampling period within the observation window is marked as the second master temperature; the difference between the second master temperature and the first master temperature is calculated and divided by the length of the observation window to obtain the temperature rise rate.

7. The adaptive heat dissipation cylindrical magnetic drive system for electric motors as described in claim 6, characterized in that: The coupling control module further includes a control unit and an execution unit; the control unit is configured with a gap control strategy for calculating the gap adjustment amount of the axial gap (5); the control unit generates an adjustment command based on the gap adjustment amount and sends it to the execution unit; the execution unit parses the adjustment command to obtain the gap adjustment amount, and adjusts the gap distance of the axial gap (5) based on the gap adjustment amount, including driving the permanent magnet rotor (2) to move axially along the rotation axis, so that after the permanent magnet rotor (2) moves, the gap distance is reduced compared to before the permanent magnet rotor (2) moves, and the reduction amount is equal to the gap adjustment amount.

8. The adaptive heat dissipation cylindrical magnetic drive system for electric motors as described in claim 7, characterized in that: The gap control strategy includes: Based on the slip ratio, the main control temperature, and the temperature rise rate, the slip deviation and the heat accumulation are calculated; the values ​​of the slip deviation and the heat accumulation are both in the range of 0 to 1. Calculate the fuzzy membership degree of the slip deviation degree and the fuzzy membership degree of the heat accumulation degree respectively; the fuzzy membership degree of either slip deviation degree or heat accumulation degree includes a first membership degree, a second membership degree, and a third membership degree. A reference adjustment strength is set; the reference adjustment strength includes a first adjustment strength, a second adjustment strength, and a third adjustment strength; the value of any one of the reference adjustment strengths is between 0 and 1; Assign a correlation membership degree to each reference regulation strength, and determine the activation degree of each reference regulation strength based on the correlation membership degree; calculate the overall regulation strength based on the activation degree of each reference regulation strength. The maximum gap adjustment amount is determined based on the gap distance; the product of the comprehensive adjustment intensity and the maximum gap adjustment amount is calculated as the gap adjustment amount.

9. The adaptive heat dissipation cylindrical magnetic drive system for electric motors as described in claim 8, characterized in that: The calculation of slip deviation and heat accumulation specifically includes: Calculate the mean slip rate for each sampling period within the observation window, and use it as the reference slip rate; calculate the mean second temperature for each sampling period within the observation window, and use it as the reference second temperature; The slip deviation is assigned a value based on the reference slip rate; the slip deviation is positively correlated with the reference slip rate. The temperature deviation is assigned a value based on the reference second temperature; the temperature deviation ranges from 0 to 1 and is positively correlated with the reference second temperature; The temperature rise deviation is assigned a value based on the temperature rise rate; the temperature rise deviation ranges from 0 to 1 and is positively correlated with the temperature rise rate. The larger of the temperature deviation and the temperature rise deviation is taken as the heat accumulation degree.

10. The adaptive heat dissipation cylindrical magnetic drive system for an electric motor as described in claim 9, characterized in that: Determining the activation of any reference regulation strength specifically includes: marking the association membership degree with reference regulation strength greater than 0 as its effective association membership degree; taking the minimum value among the effective association membership degrees as the activation of the reference regulation strength; if any reference regulation strength has no effective association membership degree, then its activation is recorded as 0. The calculation of the overall regulation strength specifically includes: calculating the product of each reference regulation strength and its corresponding activation level as the trigger strength; and calculating the sum of the trigger strengths of all reference regulation strengths to obtain the overall regulation strength.

Images