A brushless outer-rotor motor cooperative control system and method

Abstract

The application discloses a brushless outer rotating motor cooperative control system and method. The system comprises a motor structure and an integrated electric control board. A sensor is embedded in the end of the U-shaped slot silicon steel sheet stator of the motor structure, and a micro magnetic steel position Hall sensor array is embedded in the outer wall of the barium neodymium ferrite ring embracing broken magnetic steel rotor. The rear cover is made of die-cast aluminum or aluminum-silicon alloy material and integrally formed with a heat sink and a buckle type exclusive reserved cavity. The integrated electric control board is embeddedly installed in the cavity, the control chip of which is provided with a core database and is configured to inhibit the cogging torque based on the stator exclusive magnetic circuit parameters, and to identify the load level and dynamically adjust the power output according to the real-time collected torque and current signals. Through the deep coupling of structure and control, the application solves the problems of low speed jamming and poor dynamic load adaptability, while retaining the advantages of small size and high power of the motor with a diameter of 70 mm and a power of 0.75 HP, and is suitable for the light commercial high-frequency use scene in the gym.

Description

Technical Field

[0001] This invention belongs to the field of brushless motor control technology, specifically, it relates to a brushless external rotating motor cooperative control system and method. Background Technology

[0002] Brushless external rotary motors, due to their advantages such as small size, high power density, low operating noise, and long service life, have gradually replaced traditional brushed motors as the core power component of light commercial treadmills. Light commercial treadmills are used in high-frequency usage scenarios such as gyms, and are characterized by a wide range of user weights (50-150kg), diverse operating states (walking / jogging / sprinting / sudden stops), and a high demand for low-speed walking. This places stringent requirements on the control precision, load adaptability, power response speed, and energy efficiency of the matching brushless external rotary motor.

[0003] In existing technologies, brushless external motors used in treadmills generally suffer from the following technical defects: The control algorithm is disconnected from the motor structure. Many treadmills use generic dual-loop speed / current control algorithms without incorporating customized control strategies specific to their motors. This results in poor cogging torque suppression at low speeds, causing noticeable jerking during the 0-2km / h walking phase and a poor user experience. Furthermore, the motors often employ constant power or constant speed control, failing to accurately adjust power output based on dynamic load changes. This leads to excessive energy consumption under light loads, delayed power response under heavy loads, and vibrations and sudden speed changes during extreme heavy load stops. Additionally, the sensor acquisition system suffers from low accuracy and high latency. Traditional sensors are often externally mounted, making them susceptible to electromagnetic interference and exhibiting poor fit with the motor stator and rotor, hindering accurate acquisition of core signals such as electrical angle, magnet position, and speed fluctuations. This results in large errors in the data source provided to the control algorithm. While some motors use embedded sensors, the poorly designed embedding structure disrupts the stator magnetic circuit distribution, affecting power density and operational stability. To address the aforementioned issues, there is an urgent need to develop a collaborative control system and control method that is deeply coupled with the customized structure of the brushless external rotary motor. This would enable the structure to empower the control and maximize the performance of the structure through integrated innovation, thereby solving problems such as low-speed lag, power fluctuations due to sudden load changes, and low energy efficiency in treadmills. Summary of the Invention

[0004] In view of this, the technical problem to be solved by the present invention is to provide a brushless external motor collaborative control system and control method, which solves the technical problems of low-speed jamming, poor dynamic load adaptability, power response delay, low energy efficiency, low sensor acquisition accuracy, and disconnect between structure and control of existing brushless external motors used in treadmills, while ensuring that the motor retains the core design advantages of small size and high power, and is suitable for high-frequency use scenarios in gyms and light commercial settings.

[0005] To achieve the above-mentioned technical objectives, this invention discloses a brushless external rotating motor cooperative control system, including a motor structure and an integrated electronic control board; The motor structure includes a stator assembly, a rotor assembly, an end cover assembly, and a housing; The stator assembly is made of U-shaped slot silicon steel sheets. The slot depth, slot width, slot opening curvature and stacking coefficient of the U-shaped slot silicon steel sheets are precisely calibrated and form a dedicated magnetic circuit parameter library. The three-phase winding ends of the stator assembly are provided with miniature sealed embedding slots. Platinum resistance temperature sensors and high-resolution linear Hall position sensors are embedded in the embedding slots. The embedding slots are sealed with epoxy resin potting. The sensors are seamlessly attached to the stator core and do not change the power density of the motor. The rotor assembly adopts a barium neodymium ferrite ring-shaped fractured magnet structure. A miniature magnet position Hall sensor array is embedded in the non-magnetic area corresponding to the magnet fracture on the outer side wall of the rotor. A high-temperature resistant magnetic insulating coating is sprayed between the sensor array and the magnet surface. The end cover assembly includes a front cover made of cast iron and a rear cover made of die-cast aluminum or aluminum-silicon alloy. The rear cover is integrally formed with heat sinks and has a snap-fit ​​dedicated reserved cavity inside. The outer casing is made of No. 20 steel shaped tubing, which, together with the end cover assembly, forms an overall encapsulation structure for the motor. The integrated electronic control board is embedded in a dedicated reserved cavity in the rear cover and is electrically connected to the platinum resistance temperature sensor, high-resolution linear Hall position sensor, and miniature magnet position Hall sensor array embedded in the stator assembly. The electronic control board is equipped with a power drive module and a control chip with a built-in core database. The control chip is configured to suppress the cogging torque of the motor based on the exclusive magnetic circuit parameters of the U-groove silicon steel sheet stator, and to identify the load level and dynamically adjust the power output according to the real-time collected motor torque and current signals.

[0006] Furthermore, the control chip is configured to build a cogging torque waveform library by: calculating the theoretical value of the cogging torque of the U-slot silicon steel sheet stator at different electrical angles through finite element simulation, performing multiple rounds of calibration in combination with the actual no-load test data of the motor, generating motor-specific cogging torque-electric angle matching waveform data, and storing the data in the core database of the control chip.

[0007] Furthermore, the control chip is configured to perform cogging torque suppression using a composite drive method that superimposes a three-phase current sine wave with a customized harmonic compensation component; wherein the compensation coefficient is amplified by 1.2 times in the low-speed range of 0-2km / h of the motor, and the compensation coefficient is automatically reduced to the standard value when the motor speed is higher than 2km / h, ultimately suppressing the motor cogging torque to less than 2% of the rated torque.

[0008] Furthermore, the load classification standard preset in the control chip is divided into four levels based on the real-time torque value of the motor: L1 light load, L2 medium load, L3 heavy load, and L4 extremely heavy load. Each level corresponds to different torque ranges, power output thresholds, speed-torque matching curves, and power adjustment strategies.

[0009] Furthermore, the power regulation strategy executed by the control chip after identifying the load level is as follows: for L1 light load and L2 medium load, a speed-priority regulation strategy is adopted; for L3 heavy load, a torque-priority regulation strategy is switched, and the power output can be increased to the corresponding threshold within 0.3ms; for L4 extremely heavy load, a sub-strategy of rapid load shedding, inertial buffering, and energy recovery is adopted. When the energy recovery sub-strategy detects that the motor speed drops sharply by more than 30%, it cuts off the high-power output and converts the rotor inertial kinetic energy into electrical energy to feed back to the electronic control board capacitor.

[0010] Furthermore, the miniature sealing groove of the stator assembly is sealed with epoxy resin potting, and the sensor is seamlessly attached to the stator core, without affecting the stator magnetic circuit distribution and winding insulation; the sensor array of the rotor assembly is coated with a high-temperature resistant magnetic insulating coating between itself and the magnet surface.

[0011] Furthermore, the back cover is integrally molded with a heat sink, and the power devices of the integrated electronic control board are closely attached to the heat sink.

[0012] This invention also provides a brushless external motor collaborative control method based on the above-mentioned collaborative control system, applied to a light commercial treadmill, comprising the following steps: S1. Signal Acquisition: The stator temperature, motor electrical angle and speed signals are acquired in real time through the stator sensing component. The actual rotation position of the magnet, speed fluctuation and the relative position of the rotor and stator are acquired in real time through the rotor sensing component. All acquired signals are transmitted to the control chip of the integrated electronic control board in real time with a delay of <0.5ms. S2, Cogging Torque Suppression: The control chip calls the motor-specific cogging torque waveform library pre-stored in the core database, retrieves the corresponding compensation current amplitude, phase and timing based on the real-time collected motor electrical angle, and superimposes the reverse harmonic compensation component onto the basic drive current to generate a PWM drive signal; S3. Load Level Identification and Power Adjustment: The control chip identifies the current load level of the light commercial treadmill based on the real-time collected motor torque and current signals, and retrieves the corresponding power output threshold, speed-torque matching curve and power adjustment strategy from the core database, and outputs a power adjustment command to the power drive module; if a load level switch is detected, the power output is gradually adjusted using a gradient power adjustment method. S4, Motor Drive: The control chip synchronously outputs the PWM drive signal generated in step S2 and the power adjustment command in step S3 to the power drive module, which then controls the operation of the brushless external motor. S5. Real-time feedback correction: The stator and rotor sensing components continuously collect motor operation signals, and the control chip dynamically adjusts the compensation current parameters and power output commands based on the real-time signals to achieve closed-loop control.

[0013] Furthermore, the specific adjustment method for cogging torque suppression in step S2 is as follows: in the low-speed range of 0-2km / h of the motor, the compensation coefficient is amplified by 1.2 times to enhance the suppression effect, so that the cogging torque is reduced to less than 2% of the rated torque; when the motor speed is higher than 2km / h, the compensation coefficient is automatically reduced to the standard value, and the proportion of harmonic compensation components is gradually reduced.

[0014] Furthermore, the specific criteria for load level identification in step S3 are as follows: L1 Light Load: Motor torque ≤ 30% of rated torque, corresponding to users weighing 50-80kg walking on the treadmill; L2 medium load: The motor torque is 30%-60% of the rated torque, which corresponds to users weighing 80-120kg walking on the treadmill or users weighing 50-80kg jogging on the treadmill. L3 Heavy-Duty: The motor torque is 60%-90% of the rated torque, which corresponds to a 120-150kg user walking on the treadmill or an 80-120kg user jogging on the treadmill. L4 Extremely Heavy Load: Motor torque > 90% of rated torque, corresponding to users weighing 120-150kg sprinting on the treadmill or during the transition phase of a sudden stop on the treadmill.

[0015] Furthermore, the power regulation strategy in step S3 is as follows: For L1 light load and L2 medium load, a speed-priority adjustment strategy is adopted to smoothly adjust the power output and reduce energy consumption. For L3 heavy load, a torque-priority regulation strategy is adopted to increase the power output to the corresponding threshold within 0.3ms; For L4 heavy load, the starting power is quickly cut off, inertial buffer and energy recovery sub-strategy are implemented. When the motor speed drops by more than 30%, the high power output is immediately cut off, and the rotor inertial kinetic energy is converted into electrical energy and fed back to the electronic control board capacitor.

[0016] Compared with the prior art, the present invention can achieve the following technical effects: A customized cogging torque waveform library is constructed based on the exclusive magnetic circuit parameters of the U-groove silicon steel sheet stator. A composite drive method with enhanced compensation in the low-speed range is adopted to suppress the cogging torque to below 2% of the rated torque. This ensures smooth operation without any jerking during the 0-2km / h low-speed walking phase. A four-level load classification standard specifically designed for light commercial treadmills is employed, coupled with differentiated power adjustment strategies. This achieves energy saving under light loads, strong power under heavy loads, and stable transition under extremely heavy loads. For users weighing 50-150kg, the motor's power response time is short under all operating conditions, with no speed drops or machine vibration issues. Through load-level on-demand power output and energy recovery strategies for sudden stops under extremely heavy loads, the overall energy efficiency of the motor is improved, and energy consumption during sudden stops is reduced. Embedded stator and rotor sensing components are used, with a platinum resistance temperature sensor having a data acquisition accuracy of ±0.2℃ and a Hall effect position sensor. The sensor's electrical angle recognition accuracy is ±1°, and the signal acquisition delay is <0.5ms. Furthermore, the sensor installation does not disrupt the motor's magnetic circuit distribution or winding insulation. The motor structure provides dedicated hardware support for the control module, with pre-reserved sensor mounting positions on the stator and rotor. The rear cover features a dedicated mounting cavity for the control board, and the power devices on the control board are integrated with the rear cover's heat sink, achieving zero-delay transmission of control signals and efficient heat dissipation for the power devices. All structural modifications are miniaturized embedded designs, retaining the motor's small size (70mm diameter) and high power (0.75HP). Closed-loop real-time feedback corrects and dynamically adjusts control parameters, preventing motor failures caused by power surges and current distortion. Simultaneously, the integrated design of the sensor, control, and motor structure enhances the motor's overall protection, significantly extending its actual service life in the sweaty, high-frequency use environment of a gym.

[0017] Of course, any product implementing this invention does not necessarily need to achieve all of the technical effects described above at the same time. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a three-dimensional view of the brushless external rotary motor cooperative control system in an embodiment of the present invention.

[0019] Figure 2 This is a cross-sectional view of the brushless external rotary motor cooperative control system in an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the internal workings of the brushless external rotary motor collaborative control system in an embodiment of the present invention.

[0021] Figure 4 This is a flowchart of the brushless external rotary motor collaborative control method in an embodiment of the present invention.

[0022] Figure label: 1-Stator assembly, 11-U-slot silicon steel sheet, 12-Embedded slot, 2-Rotor assembly, 21-Barium neodymium ferrite-enclosed fracture magnet, 22-Miniature magnet position Hall sensor array, 3-End cover assembly, 31-Front cover, 32-Rear cover, 322-Snap-on dedicated reserved cavity, 4-Outer shell, 5-Integrated electronic control board. Detailed Implementation

[0023] The following will describe in detail the implementation of the present invention with reference to the accompanying drawings and embodiments, so that the process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0024] Example 1: Brushless External Rotary Motor Cooperative Control System This embodiment provides a brushless external motor collaborative control system suitable for light commercial treadmills. For example... Figures 1-3 As shown, the system includes a motor structure and an integrated electronic control board 5.

[0025] The motor structure includes a stator assembly 1, a rotor assembly 2, an end cover assembly 3, and a housing 4.

[0026] The stator assembly 1 is made of U-shaped slot silicon steel sheets 11. The slot depth, slot width, slot opening curvature and stacking coefficient of the U-shaped slot silicon steel sheets 11 are accurately calibrated through finite element simulation analysis and experimental verification to form a dedicated magnetic circuit parameter library for the motor, providing underlying data support for subsequent control algorithms.

[0027] Miniature sealed mounting slots 12 are formed at the ends of the three-phase windings of the stator assembly 1. These slots 12 contain stator sensing components, including a platinum resistance temperature sensor and a high-resolution linear Hall effect position sensor. The platinum resistance temperature sensor is used to acquire stator temperature with an accuracy of ±0.2℃; the high-resolution linear Hall effect position sensor is used to acquire motor electrical angle and speed signals with an electrical angle recognition accuracy of ±1°. The mounting slots 12 are sealed with epoxy resin to ensure seamless contact between the sensors and the stator core, without affecting the stator magnetic circuit distribution or winding insulation, and without altering the motor's power density.

[0028] The rotor assembly 2 employs a barium-neodymium ferrite-encircled fractured magnet 21 structure. A rotor sensing component, a miniature magnet position Hall sensor array 22, is embedded in the non-magnetic region corresponding to the magnet fracture on the outer wall of the rotor. A high-temperature resistant magnetic insulating coating (withstanding temperatures ≥150℃) is sprayed between the sensor array and the magnet surface to effectively prevent electromagnetic interference. This sensor array is used to acquire the actual rotational position of the magnet, speed fluctuations, and the relative position signals between the rotor and stator.

[0029] The end cover assembly 3 includes a front cover 31 and a rear cover 32. The front cover 31 is made of cast iron to ensure the structural strength of the motor's load-bearing end; the rear cover 32 is made of die-cast aluminum or an aluminum-silicon alloy, balancing lightweight design and heat dissipation. The rear cover 32 is integrally molded with heat sinks for cooling power devices. The rear cover 32 also has a snap-fit ​​dedicated cavity 322 inside, the shape and size of which match the integrated electronic control board 5, facilitating the embedded installation of the electronic control board and subsequent disassembly and maintenance.

[0030] The outer casing 4 is made of 20# steel shaped tubing, which is bolted to the end cap assembly 3 to form an integral motor enclosure structure. The shaped tubing design is adapted to the installation space of light commercial treadmills, and the overall structure ensures the motor's compact size (70mm diameter) while providing sufficient structural strength and protection. The motor's rated power can reach 0.75HP (550W).

[0031] The integrated electronic control board 5 is embedded in the dedicated reserved cavity 322 of the rear cover 32 and is fixed by a snap-fit. The electronic control board 5 is electrically connected to the platinum resistance temperature sensor, the high-resolution linear Hall position sensor embedded in the stator assembly 1, and the miniature magnet position Hall sensor array 22 embedded in the rotor assembly via high-temperature resistant wires.

[0032] The control board 5 is equipped with a power drive module 51 and a control chip 52 with a built-in core database. The control chip 52 is a high-performance MCU chip. The power devices (such as MOSFETs) of the control board 5 are closely attached to the heat sink of the back cover 32 to achieve efficient heat dissipation; the embedded installation shortens the signal transmission path and realizes zero-delay transmission of control signals.

[0033] The control chip has a built-in core database and is configured to perform collaborative control functions, mainly including two modules: cogging torque suppression and load-level adaptive power regulation.

[0034] In detail, the control chip calculates the theoretical value of the cogging torque of the U-slot silicon steel sheet stator 11 under electrical angles of 0-360° through finite element simulation, performs multiple rounds of calibration in combination with the actual no-load test data of the motor, generates the cogging torque-electric angle matching waveform data specific to the motor, and stores it in the core database.

[0035] During operation, the control chip retrieves the corresponding compensation current amplitude, phase, and timing from the database based on the real-time electrical angle acquired by the high-resolution linear Hall position sensor. It then employs a composite drive method that superimposes a three-phase current sine wave with a customized harmonic compensation component, outputting compensation commands to the power drive module. Specifically, in the low-speed range of 0-2 km / h, the compensation coefficient is amplified by 1.2 times to enhance the suppression effect; when the motor speed exceeds 2 km / h, the compensation coefficient is automatically reduced to the standard value, gradually decreasing the proportion of harmonic compensation components and avoiding current distortion in the high-frequency range. Ultimately, the cogging torque is suppressed to below 2% of the rated torque.

[0036] The control chip identifies the current load level based on motor torque and current signals acquired by the platinum resistance temperature sensor and Hall sensor, according to a preset four-level load classification standard. The preset load classification standard is as follows: L1 Light Load: Motor torque ≤ 30% of rated torque; L2 medium load: Rated torque 30% < motor torque ≤ 60% of rated torque; L3 Heavy Load: Rated torque 60% < Motor torque ≤ 90% of Rated torque; L4 Extremely Heavy Load: Motor torque > 90% of rated torque.

[0037] After identifying the load level, the control chip retrieves the corresponding power output threshold, speed-torque matching curve, and power regulation strategy from the core database, and outputs instructions to the power drive module: For L1 light load and L2 medium load, a speed-priority adjustment strategy is adopted to smoothly adjust the power output and reduce energy consumption. For L3 heavy load, the torque-priority regulation strategy is switched to increase the power output to the corresponding threshold within 0.3ms, ensuring a power response without delay. For L4 heavy load, the starting power is quickly cut off, and the inertial buffer and energy recovery sub-strategy is implemented. When the motor speed drops by more than 30%, the high power output is immediately cut off, and the rotor inertial kinetic energy is converted into electrical energy and fed back to the energy storage capacitor of the control board to achieve energy recovery.

[0038] Example 2: Collaborative Control Method for Brushless External Rotary Motor This embodiment, based on the collaborative control system of Embodiment 1, provides a collaborative control method for a brushless external motor suitable for light commercial treadmills. For example... Figure 4 As shown, the method includes the following steps: S1, Signal Acquisition The stator sensing components acquire stator temperature, motor electrical angle, and speed signals in real time, while the rotor sensing components acquire the actual rotational position of the magnets, speed fluctuations, and the relative position of the rotor and stator in real time. All acquired signals are transmitted in real time to the control chip of the integrated electronic control board 5 via high-temperature resistant wires with a delay of <0.5ms.

[0039] S2, Cogging torque suppression The control chip calls the motor-specific cogging torque waveform library pre-stored in the core database, retrieves the corresponding compensation current amplitude, phase and timing based on the real-time collected motor electrical angle (identification accuracy ±1°), and superimposes the reverse harmonic compensation component onto the basic drive current to generate a PWM drive signal.

[0040] The specific adjustment method is as follows: in the low speed range of 0-2km / h of the motor, the compensation coefficient is amplified by 1.2 times to enhance the suppression effect, so that the cogging torque is reduced to less than 2% of the rated torque; when the motor speed is higher than 2km / h, the compensation coefficient is automatically reduced to the standard value, gradually reducing the proportion of harmonic compensation components and avoiding high-frequency current distortion.

[0041] S3, Load Level Identification and Power Regulation The control chip identifies the current load level of the treadmill according to a four-level load classification standard based on real-time collected motor torque and current signals. The specific classification and its correspondence with user scenarios are as follows: L1 Light Load: Motor torque ≤ 30% of rated torque, corresponding to users weighing 50-80kg walking on the treadmill; L2 medium load: The motor torque is 30%-60% of the rated torque, which corresponds to users weighing 80-120kg walking on the treadmill or users weighing 50-80kg jogging on the treadmill. L3 Heavy-Duty: The motor torque is 60%-90% of the rated torque, which corresponds to a 120-150kg user walking on the treadmill or an 80-120kg user jogging on the treadmill. L4 Extremely Heavy Load: Motor torque > 90% of rated torque, corresponding to users weighing 120-150kg sprinting on the treadmill or during the transition phase of a sudden stop on the treadmill.

[0042] After identification, the control chip retrieves the power output threshold, speed-torque matching curve, and power adjustment strategy corresponding to the load level from the core database, and outputs a power adjustment command to the power drive module. If a load level change is detected, a gradient power adjustment method is used to gradually adjust the power output to avoid motor torque fluctuations and treadmill body vibrations caused by sudden power changes.

[0043] The power regulation strategy is as follows: For L1 light load and L2 medium load, a speed-priority adjustment strategy is adopted to smoothly adjust the power output and reduce energy consumption. For L3 heavy load, a torque-priority regulation strategy is adopted to increase the power output to the corresponding threshold within 0.3ms; For L4 heavy load, the starting power is quickly cut off, inertial buffer and energy recovery sub-strategy are implemented. When the motor speed drops by more than 30%, the high power output is immediately cut off, and the rotor inertial kinetic energy is converted into electrical energy and fed back to the electronic control board capacitor.

[0044] S4, motor drive The control chip synchronously outputs the PWM drive signal generated in step S2 and the power adjustment command in step S3 to the power drive module, which then controls the operating speed and power output of the brushless external rotary motor according to the command.

[0045] S5, Real-time Feedback Correction The stator sensing component 13 and the rotor sensing component 22 continuously collect the real-time operating signals of the motor. The control chip compares the collected signals with the preset operating parameters and dynamically adjusts the compensation current parameters and power output commands according to the comparison results to realize closed-loop control of the motor and ensure the stability of the motor operation under all working conditions.

[0046] The control method of this embodiment can improve the energy efficiency of the brushless external motor to over 94%, reduce energy consumption by 15% under sudden stop conditions of the treadmill, and ensure that the motor does not jam, slow down, or vibrate when users of all weights (50-150kg) are walking, jogging, sprinting, or stopping on the treadmill.

[0047] Example 3: Light Commercial Treadmill This embodiment provides a light commercial treadmill, which includes the brushless external motor collaborative control system of Embodiment 1. This motor system serves as the core power component of the treadmill and is connected to the treadmill rollers via a spline quick-connect connection. The motor's operating status is controlled through the treadmill's control panel. This treadmill enables smooth walking at low speeds, stable sprints at high speeds, and smooth transitions to sudden stops, significantly improving the user experience and operational stability, and is suitable for the high-frequency, multi-user needs of light commercial settings such as gyms.

[0048] The foregoing description illustrates and describes several preferred embodiments of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A brushless external rotary motor collaborative control system, characterized in that, This includes the motor structure and the integrated electronic control board; The motor structure includes a stator assembly, a rotor assembly, an end cover assembly, and a housing. The stator assembly is made of U-shaped slot silicon steel sheets. The slot depth, slot width, slot opening curvature and stacking coefficient of the U-shaped slot silicon steel sheets are precisely calibrated and form a dedicated magnetic circuit parameter library. The three-phase winding ends of the stator assembly are provided with miniature sealed embedding slots. Platinum resistance temperature sensors and high-resolution linear Hall position sensors are embedded in the embedding slots. The embedding slots are sealed with epoxy resin potting. The sensors are seamlessly attached to the stator core and do not change the power density of the motor. The rotor assembly adopts a barium neodymium ferrite ring-shaped fractured magnet structure. A miniature magnet position Hall sensor array is embedded in the non-magnetic area corresponding to the fracture of the magnet on the outer side wall of the rotor. A high-temperature resistant magnetic insulating coating is sprayed between the sensor array and the magnet surface. The end cap assembly includes a front cover and a rear cover, and the rear cover has a snap-fit ​​dedicated reserved cavity inside; The outer casing and the end cap assembly cooperate to form an overall motor enclosure structure; The integrated electronic control board is embedded in the dedicated reserved cavity of the rear cover and is electrically connected to the platinum resistance temperature sensor, the high-resolution linear Hall position sensor embedded in the stator assembly, and the miniature magnet position Hall sensor array embedded in the rotor assembly. The electronic control board is equipped with a power drive module and a control chip with a built-in core database. The control chip is configured to suppress the cogging torque of the motor based on the exclusive magnetic circuit parameters of the U-groove silicon steel sheet stator, and to identify the load level and dynamically adjust the power output according to the real-time collected motor torque and current signals.

2. The brushless external rotary motor cooperative control system according to claim 1, characterized in that, The control chip is configured to build a cogging torque waveform library by: calculating the theoretical value of the cogging torque of the U-groove silicon steel sheet stator at different electrical angles through finite element simulation, performing multiple rounds of calibration in combination with the actual no-load test data of the motor, generating motor-specific cogging torque-electric angle matching waveform data, and storing the data in the core database of the control chip.

3. The brushless external rotary motor cooperative control system according to claim 1, characterized in that, The control chip is configured to perform cogging torque suppression using a composite drive method that superimposes a three-phase current sine wave with a customized harmonic compensation component. Specifically, the compensation coefficient is amplified by 1.2 times in the low-speed range of 0-2 km / h, and the compensation coefficient is automatically reduced to the standard value when the motor speed is higher than 2 km / h, ultimately suppressing the motor cogging torque to less than 2% of the rated torque.

4. The brushless external rotary motor cooperative control system according to claim 1, characterized in that, The load classification standard preset in the control chip is divided into four levels based on the real-time torque value of the motor: L1 light load, L2 medium load, L3 heavy load, and L4 extremely heavy load. Each level corresponds to a different torque range, power output threshold, speed-torque matching curve, and power adjustment strategy.

5. The brushless external rotary motor cooperative control system according to claim 4, characterized in that, The power regulation strategy executed by the control chip after identifying the load level is as follows: for L1 light load and L2 medium load, a speed-priority regulation strategy is adopted; for L3 heavy load, a torque-priority regulation strategy is switched, and the power output can be increased to the corresponding threshold within 0.3ms; for L4 extremely heavy load, a sub-strategy of rapid load shedding, inertial buffering and energy recovery is adopted. When the energy recovery sub-strategy detects that the motor speed drops sharply by more than 30%, it cuts off the high-power output and converts the rotor inertial kinetic energy into electrical energy to feed back to the electronic control board capacitor.

6. The brushless external rotary motor cooperative control system according to claim 1, characterized in that, The miniature sealing groove of the stator assembly is sealed with epoxy resin potting, and the sensor is seamlessly attached to the stator core, without affecting the stator magnetic circuit distribution and winding insulation; the sensor array of the rotor assembly is coated with a high-temperature resistant magnetic insulating coating between itself and the surface of the magnet.

7. A method for coordinated control of a brushless external motor based on the coordinated control system described in any one of claims 1 to 6, applied to a light commercial treadmill, characterized in that, Includes the following steps: S1. Signal Acquisition: The stator temperature, motor electrical angle and speed signals are acquired in real time through the stator sensing component. The actual rotation position of the magnet, speed fluctuation and the relative position of the rotor and stator are acquired in real time through the rotor sensing component. All acquired signals are transmitted to the control chip of the integrated electronic control board in real time with a delay of <0.5ms. S2, Cogging Torque Suppression: The control chip calls the motor-specific cogging torque waveform library pre-stored in the core database, retrieves the corresponding compensation current amplitude, phase and timing based on the real-time collected motor electrical angle, and superimposes the reverse harmonic compensation component onto the basic drive current to generate a PWM drive signal; S3. Load Level Identification and Power Adjustment: The control chip identifies the current load level of the light commercial treadmill based on the real-time collected motor torque and current signals, and retrieves the corresponding power output threshold, speed-torque matching curve and power adjustment strategy from the core database, and outputs a power adjustment command to the power drive module; if a load level switch is detected, the power output is gradually adjusted using a gradient power adjustment method. S4, Motor Drive: The control chip synchronously outputs the PWM drive signal generated in step S2 and the power adjustment command in step S3 to the power drive module, which then controls the operation of the brushless external motor. S5. Real-time feedback correction: The stator and rotor sensing components continuously collect motor operation signals, and the control chip dynamically adjusts the compensation current parameters and power output commands based on the real-time signals to achieve closed-loop control.

8. The brushless external rotary motor cooperative control method according to claim 7, characterized in that, The specific adjustment method for suppressing cogging torque in step S2 is as follows: in the low speed range of 0-2km / h of the motor, the compensation coefficient is amplified by 1.2 times to enhance the suppression effect, so that the cogging torque is reduced to less than 2% of the rated torque; when the motor speed is higher than 2km / h, the compensation coefficient is automatically reduced to the standard value, and the proportion of harmonic compensation components is gradually reduced.

9. The brushless external rotary motor cooperative control method according to claim 7, characterized in that, The specific criteria for load level identification in step S3 are as follows: L1 Light Load: Motor torque ≤ 30% of rated torque, corresponding to users weighing 50-80kg walking on the treadmill; L2 medium load: The motor torque is 30%-60% of the rated torque, which corresponds to users weighing 80-120kg walking on the treadmill or users weighing 50-80kg jogging on the treadmill. L3 Heavy-Duty: The motor torque is 60%-90% of the rated torque, which corresponds to a 120-150kg user walking on the treadmill or an 80-120kg user jogging on the treadmill. L4 Extremely Heavy Load: Motor torque > 90% of rated torque, corresponding to users weighing 120-150kg sprinting on the treadmill or during the transition phase of a sudden stop on the treadmill.

10. The brushless external rotary motor cooperative control method according to claim 7 or 9, characterized in that, The power regulation strategy described in step S3 is as follows: For L1 light load and L2 medium load, a speed-priority adjustment strategy is adopted to smoothly adjust the power output and reduce energy consumption. For L3 heavy load, a torque-priority regulation strategy is adopted to increase the power output to the corresponding threshold within 0.3ms; For L4 heavy load, the starting power is quickly cut off, inertial buffer and energy recovery sub-strategy are implemented. When the motor speed drops by more than 30%, the high power output is immediately cut off, and the rotor inertial kinetic energy is converted into electrical energy and fed back to the electronic control board capacitor.

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