Intelligent control system and method of permanent magnet synchronous brushless motor

Abstract

The invention discloses an intelligent control system and method for a permanent magnet synchronous brushless motor, and the method comprises the steps: measuring a rotation position signal of a secondary magnetic wheel of a motor rotor through a high-resolution position sensor, and measuring a rotation position signal of a main magnetic wheel of the motor rotor through a low-resolution sensor; detecting whether the position signal increment synchronization between the rotation position signal of the secondary magnetic wheel of the motor rotor and the rotation position signal of the main magnetic wheel of the motor rotor is completed within a set time or not; when the rotation position signal of the secondary magnetic wheel of the motor rotor and the rotation position signal of the main magnetic wheel of the motor rotor complete position signal increment synchronization within a set time, the motor enters a closed-loop control operation mode; the actual rotation position of the motor is determined according to the initial position of the motor and the rotation position signals of the motor rotor secondary magnetic wheel and the motor rotor main magnetic wheel, and the actual rotation position of the motor is adjusted according to the difference value between the actual rotation position of the motor and the target rotation position of the motor to reach the target rotation position of the motor.

Description

Technical Field

[0001] This invention relates to the field of motor control, specifically to an intelligent control system and method for a permanent magnet synchronous brushless motor. Background Technology

[0002] With the continuous advancement of motor control technology, permanent magnet synchronous brushless motors are widely used in high-precision control scenarios such as electric vehicles and industrial automation due to their high efficiency and reliability. The requirements for the dynamic response and positional accuracy of these motors are becoming increasingly stringent. However, existing control methods, such as trapezoidal wave control, suffer from vibration and noise problems caused by sudden changes in commutation current; direct torque control suffers from harmonic interference and poor low-speed performance due to inconsistent switching frequencies; model predictive control requires high computing power and is easily affected by model errors; and vector control algorithms are complex and rely on high-performance controllers. These shortcomings collectively limit the accuracy, stability, and robustness of control systems, making it difficult to meet the millimeter-level precision control requirements of modern applications such as lift or valve opening control. Summary of the Invention

[0003] The purpose of this invention is to provide an intelligent control system for a permanent magnet synchronous brushless motor and an intelligent control method for a permanent magnet synchronous brushless motor. The system and method achieve real-time measurement and incremental synchronous detection of rotational position signals by integrating high-resolution and low-resolution position sensors. After confirming synchronization, the system switches to a closed-loop control mode and adjusts the motor operating parameters based on the initial position of the motor and the dynamic difference between the actual and target rotational positions, thereby achieving precise control of the permanent magnet synchronous brushless motor.

[0004] To achieve this objective, the present invention provides an intelligent control system for a permanent magnet synchronous brushless motor, comprising: The sensor measurement module is used to measure the rotational position signal of the secondary magnetic wheel of the motor rotor using a high-resolution position sensor, and to measure the rotational position signal of the main magnetic wheel of the motor rotor using a low-resolution sensor. The synchronization detection module is used to detect whether the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed incremental synchronization of position signals within a set time. When the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed incremental synchronization of position signals within a set time, the motor enters the closed-loop control operation mode. The closed-loop control module is used to determine the actual rotation position of the motor in the closed-loop control operation mode of the motor based on the initial position of the motor, the rotation position signals of the secondary magnetic wheel of the motor rotor and the main magnetic wheel of the motor rotor, and adjust the actual rotation position of the motor according to the difference between the actual rotation position and the target rotation position of the motor to achieve the target rotation position of the motor.

[0005] Preferably, an intelligent control system for a permanent magnet synchronous brushless motor further includes: a synchronization fault detection module for continuously detecting whether the position signal increment between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor remains synchronized in the motor closed-loop control mode; when an asynchronous fault occurs between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor, the asynchronous fault is recorded and a de-jittering operation is performed; otherwise, the motor operates normally.

[0006] Furthermore, there are multiple high-resolution position sensors and multiple low-resolution position sensors, and the multiple high-resolution position sensors and low-resolution position sensors are arranged at a set angle.

[0007] Furthermore, the method for detecting whether the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed position signal increment synchronization within a set time includes: within a set time, if the position signal step size increment between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor exceeds a set step size, the synchronization fails; otherwise, the synchronization succeeds. Furthermore, if the position signal step between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor fails to synchronize multiple times within a set time, the synchronization is restarted until synchronization is successful.

[0008] Furthermore, when an asynchronous fault occurs between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor, the method for recording the asynchronous fault and performing de-jittering operation includes: within a fault detection cycle in the motor closed-loop control mode, when the number of times the position signal increment between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor is asynchronous exceeds a first set threshold, a rotational position signal asynchronous fault is marked; when the number of consecutive occurrences of the rotational position signal asynchronous fault mark exceeds a second set threshold, a rotational position signal asynchronous fault is recorded, and the motor is stopped or degraded; if no rotational position signal asynchronous fault mark appears in multiple consecutive fault detection cycles before the number of consecutive occurrences of the rotational position signal asynchronous fault mark exceeds the second set threshold, the rotational position signal asynchronous fault mark count is cleared to zero, the motor has no rotational position signal asynchronous fault, and operates normally.

[0009] Furthermore, the method for obtaining the actual rotational position of the motor includes: obtaining the initial position of the motor based on the current actual lift position of the helical eccentric shaft; and obtaining the actual lift position of the helical eccentric shaft driven by the motor rotation based on the rotation angle of the secondary magnetic wheel or the main magnetic wheel of the motor rotor, which is the actual rotational position of the motor.

[0010] Furthermore, the method for adjusting the actual rotation position of the motor to reach the target rotation position based on the difference between the actual rotation position and the target rotation position includes: the PID controller drives the motor to rotate to the target lift position of the helical eccentric shaft based on the difference between the actual lift position and the target lift position of the helical eccentric shaft, wherein the target lift position of the helical eccentric shaft is obtained from a pre-calibrated target lift position lookup table.

[0011] Furthermore, an intelligent control method for a permanent magnet synchronous brushless motor based on the system described in claim 1 is characterized by comprising: The rotational position signal of the secondary magnetic wheel of the motor rotor is measured by a high-resolution position sensor, and the rotational position signal of the main magnetic wheel of the motor rotor is measured by a low-resolution sensor. The system detects whether the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed position signal increment synchronization within a set time. When the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed position signal increment synchronization within a set time, the motor enters the closed-loop control operation mode. In the closed-loop control operation mode of the motor, the actual rotation position of the motor is determined based on the initial position of the motor, the rotation position signals of the secondary magnetic wheel of the motor rotor and the main magnetic wheel of the motor rotor, and the actual rotation position of the motor is adjusted according to the difference between the actual rotation position and the target rotation position of the motor to achieve the target rotation position of the motor.

[0012] The beneficial effects of this invention are as follows: Addressing the shortcomings of existing permanent magnet synchronous brushless motor control methods, such as trapezoidal wave control (leading to vibration and noise due to sudden changes in commutation current), direct torque control (causing harmonics and poor low-speed performance due to inconsistent switching frequencies), model predictive control (requiring high computational power and being sensitive to model errors), and vector control (relying on complex algorithms and high-performance controllers), this invention utilizes the collaborative work of a control module, charging module, drive module, filtering module, diagnostic module, and the motor and sensors. The control module executes PID or FOC algorithms and processes Hall sensor feedback. The arrangement of five Hall sensors (including three commutation sensors and two high-resolution sensors) enables synchronous detection of angle increments and dynamic correction logic, supplemented by PWM regulation and anti-jitter mechanisms, such as jitter counting and fault diagnosis, ensuring closed-loop control of the motor after synchronization. Furthermore, the multi-sensor redundancy design improves angle detection accuracy to 30°, ultimately achieving high control accuracy (lift control up to 0.1 mm level), moderate computational power requirements, low vibration and noise, and strong robustness. This invention can be widely applied to precise control scenarios such as electric vehicle lift and valve opening. Attached Figure Description

[0013] Figure 1 This is a graph showing the relationship between the motor speed and torque of the present invention when the maximum allowable operating current is 40A under rated voltage; Figure 2 This is a schematic diagram showing the position of the Hall sensor on the motor rotor of the present invention; Figure 3 This is a schematic diagram of the structural composition of the present invention; Figure 4 This is a schematic diagram of the control flow of the present invention; Figure 5 This is a schematic diagram of the structure of the present invention; Figure 6 This invention relates to a continuously variable valve lift (VVL) system. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Example 1 like Figure 5 As shown, an intelligent control system for a permanent magnet synchronous brushless motor includes: The sensor measurement module is used to measure the rotational position signal of the secondary magnetic wheel of the motor rotor using a high-resolution position sensor, and to measure the rotational position signal of the main magnetic wheel of the motor rotor using a low-resolution sensor. The synchronization detection module is used to detect whether the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed incremental synchronization of position signals within a set time. When the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed incremental synchronization of position signals within a set time, the motor enters the closed-loop control operation mode. The closed-loop control module is used to determine the actual rotation position of the motor in the closed-loop control operation mode of the motor based on the initial position of the motor, the rotation position signals of the secondary magnetic wheel of the motor rotor and the main magnetic wheel of the motor rotor, and adjust the actual rotation position of the motor according to the difference between the actual rotation position and the target rotation position of the motor to achieve the target rotation position of the motor.

[0016] In some embodiments, such as Figure 3 As shown, the present invention consists of a control module, a charging module, a drive module, a filtering module, a diagnostic module, a motor, and sensors; wherein the control module may be reserved for connection to a remote control receiving device, enabling remote control.

[0017] Control module: Responsible for the overall control strategy of the motor, including the adjustment of parameters such as speed, torque, and position. It executes control algorithms (such as PID control, FOC vector control, etc.), processes feedback signals from sensors, generates PWM (pulse width modulation) signals, and controls the output of the drive module. It also enables communication and interaction with other systems.

[0018] The charging module supplies power to the system via the vehicle's 12V low-voltage circuit. This module manages the power input, providing a stable DC voltage to the system. It offers overvoltage, undervoltage, and overcurrent protection; if the small battery is depleted, a DC-DC converter can adjust the voltage level to meet the motor's needs.

[0019] The drive module, also known as the power inverter module, converts the control signal into the drive current required by the motor. It uses IGBTs to convert DC power into three-phase AC power and amplifies the PWM signal to output sufficient power to drive the motor windings. It also provides overcurrent and overheat protection functions.

[0020] Filtering module: To control the motor's precision and allow for current fluctuations, four 1000uF large capacitors are connected in parallel with the power supply, along with a 0.1uF ceramic capacitor, to suppress voltage spikes, ensuring the motor receives a stable input voltage and current.

[0021] Diagnostic module: Monitors system status in real time to ensure safe operation. Detects faults such as overcurrent, overheating, short circuits, and sensor failure. Records fault codes and triggers protection mechanisms such as degradation and shutdown.

[0022] The motor is a three-phase brushless motor with equal resistance in phases U, V, and W; rated voltage 12V, maximum no-load current 3A, maximum operating speed 5500rpm, and maximum allowable operating current under rated voltage 40A. The relationship between motor speed and torque is as follows: Figure 1 As shown, the horizontal axis represents rotational speed in rpm; the vertical axis represents torque in nm. The three-phase brushless motor (i.e., the motor described in this invention) is a low-power motor. One embodiment of this invention includes applications such as... Figure 6 The engine valve lift control mechanism shown is shown.

[0023] In some technical solutions, the synchronous fault detection module is used to continuously detect whether the position signal increment between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor remains synchronized in the motor closed-loop control mode. When an asynchronous fault occurs between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor, the asynchronous fault is recorded and a de-jittering operation is performed; otherwise, the motor operates normally.

[0024] In some technical solutions, there are multiple high-resolution position sensors and multiple low-resolution position sensors, and the multiple high-resolution position sensors and low-resolution position sensors are arranged at a set angle.

[0025] In some embodiments, the motor rotor includes a secondary magnetic wheel and a primary magnetic wheel. The primary magnetic wheel is a cavity or magnetic barrier embedded inside the rotor core, used to house the main permanent magnets. The magnetic field generated by the permanent magnets is the main source of the motor's air gap magnetic field. When current is applied to the stator windings to generate a rotating magnetic field, the magnetic field of the primary magnetic wheel interacts with it, generating a strong electromagnetic force that drives the rotor to rotate and output mechanical energy. The secondary magnetic wheel itself may not contain permanent magnets, or may contain smaller, lower-grade permanent magnets. The main function of the secondary magnetic wheel is to provide the expected low-resistivity path for the magnetic lines of force generated by the primary magnetic wheel, guiding and shaping the distribution of the magnetic field. The high-resolution position sensor is a high-resolution Hall sensor, and the low-resolution position sensor is also a low-resolution Hall sensor. There are at least two low-resolution Hall sensors and at least two high-resolution Hall sensors. The two low-resolution Hall sensors are arranged at a 120° angle interval, corresponding to a 120° phase difference between the three-phase AC phases U, V, and W. One high-resolution position sensor is positioned on the centerline of the two low-resolution Hall sensors, forming two 60° angles, creating a 60° step size position signal increment detection angle between the high-resolution position sensor and the low-resolution Hall sensors. Another high-resolution position sensor is arranged at a 30° angle with any one of the low-resolution Hall sensors, creating a 30° step size position signal increment detection angle between them. Higher precision position signal increment detection angle step sizes can be obtained by adjusting the number and angle of the high-resolution position sensors and low-resolution Hall sensors.

[0026] A preferred embodiment, such as Figure 2As shown, the main magnetic wheel 3 on the inner ring of the motor rotor has 5 pairs of magnetic poles. Since there are relatively few magnetic poles, the magnetic field changes are relatively simple. Therefore, a low-resolution Hall sensor is used to collect the position information (i.e., the rotation angle and angular velocity) of the main magnetic wheel. Three low-resolution Hall sensors 1 are evenly distributed (i.e., spaced 120° apart; the measurement accuracy of three low-resolution Hall sensors is higher than that of two low-resolution Hall sensors) on the main magnetic wheel 3. The secondary magnetic wheel 4 on the outer ring of the motor rotor has 30 pairs of magnetic poles. Since there are more magnetic poles, the magnetic field changes are more complex. Therefore, a high-resolution Hall sensor is used to collect the position information (i.e., the rotation angle and angular velocity) of the secondary magnetic wheel. Two high-resolution Hall sensors 2 are distributed on the secondary magnetic wheel.

[0027] Hall sensor groups of different resolutions are arranged on the main and secondary magnetic wheels, respectively, using a specific angular layout to achieve high-precision and high-reliability detection of the motor rotor position. Three low-resolution Hall sensors on the secondary magnetic wheel provide basic commutation signals, which, combined with two high-resolution Hall sensors on the main magnetic wheel, significantly improve the angle detection resolution to 60° and 30°, enabling fine monitoring of the rotor's rotation angle. The two sets of sensors do not operate independently; the high-resolution sensors are located on the centerline of the low-resolution sensors, allowing them to cross-check signal synchronization.

[0028] In some technical solutions, the method for detecting whether the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed position signal increment synchronization within a set time includes: within a set time, if the position signal step size increment between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor exceeds a set step size, the synchronization fails; otherwise, the synchronization succeeds. In some technical solutions, when the position signal step between the secondary magnetic wheel of the motor rotor and the main magnetic wheel of the motor rotor fails to synchronize multiple times within a set time, synchronization is restarted until synchronization is successful.

[0029] In some embodiments, the ideal state for the secondary and primary magnetic wheels of the motor rotor is synchronous rotation, and the position signal increment per unit time should be consistent. However, errors are inevitable in practical applications. The position signal step size includes 60° and 30°. Position signal increment errors below 30° are permissible and have negligible impact on motor control. Errors between 30° and 60° have a significant impact on precise motor control. That is, synchronization fails when the position signal step size increment between the secondary and primary magnetic wheels of the motor rotor exceeds ±30°; otherwise, synchronization succeeds.

[0030] When the position signal step increment between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor is successfully synchronized, it indicates that if there is no slippage or abnormality in the connection between the magnetic wheel and the rotor, the rotor position information obtained by the motor control system is accurate and consistent. The motor control system can accurately calculate the real-time position and speed of the rotor based on these rotational position signals and perform precise electronic commutation.

[0031] The angle increments of the high- and low-resolution position sensors are kept synchronized, which can not only effectively identify signal loss of synchronization caused by sensor failure, electromagnetic interference or mechanical slippage, but also distinguish between transient interference and real faults by setting a synchronization time window and the allowable number of difference steps (such as diff counting), thereby greatly improving the system's robustness against transient interference. Once a loss of synchronization is detected, the system can immediately trigger a resynchronization process or enter a degraded operation mode to prevent control errors caused by abnormal signals from a single sensor group, ensuring the absolute reliability and position accuracy of motor angle control, and providing a solid data integrity guarantee for the entire closed-loop control system.

[0032] The time-based synchronization verification mechanism effectively ensures the consistency of signal increments between high-resolution and low-resolution position sensors, thereby significantly improving the real-time performance and reliability of the overall control. This method effectively avoids cumulative errors caused by sensor step size loss by accurately detecting signal step size deviations (e.g., exceeding ±1 step size (30°) indicates failure), ensuring the accuracy of position detection. Simultaneously, the time window avoids indefinite waiting, optimizing synchronization efficiency. Furthermore, the automatic restart strategy after multiple synchronization failures further enhances the system's fault tolerance and self-recovery capabilities, preventing temporary interference from causing permanent faults. Ultimately, this allows the motor to maintain a stable and accurate operating state even under complex conditions, extending equipment lifespan and reducing maintenance requirements. In some embodiments, the time setting includes, but is not limited to, 1 second, and the number of synchronization attempts within 1 second includes, but is not limited to, 4. As shown in the table above, when the position signal increment is in an "unsynchronized" state (i.e., the synchronization count is 0 or the Hall difference is 0, and the resynchronization counter is 0), the motor controller will initiate a self-test process to attempt to establish initial synchronization. If the system still fails to synchronize after the self-test (i.e., the state changes to "resynchronized but not synchronized"), for safety reasons, the controller will command the motor to stop or enter a degraded operation mode to avoid control abnormalities caused by inaccurate position information. Once the system confirms successful synchronization (synchronization count is 1 and the Hall difference is 1, while the resynchronization counter is 1), it means that the signal increments of the high- and low-resolution Hall sensors are consistent, the position detection is reliable, and the system immediately switches to a high-precision "closed-loop control" mode. If the system has synchronized but has not undergone a resynchronization process (resynchronization counter = 0), it will be judged as "not resynchronized" and a resynchronization operation will be triggered. The purpose is to deal with possible transient interference during operation and ensure the continuous effectiveness of the synchronization state.

[0033] In some technical solutions, when an asynchronous fault occurs between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor, the method for recording the asynchronous fault and performing de-jittering operation includes: within a fault detection cycle in the motor closed-loop control mode, when the number of times the position signal increment between the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor is asynchronous exceeds a first set threshold, a rotational position signal asynchronous fault is marked; when the number of consecutive occurrences of the rotational position signal asynchronous fault mark exceeds a second set threshold, a rotational position signal asynchronous fault is recorded, and the motor is stopped or degraded; if no rotational position signal asynchronous fault mark appears in multiple consecutive fault detection cycles before the number of consecutive occurrences of the rotational position signal asynchronous fault mark exceeds the second set threshold, the rotational position signal asynchronous fault mark count is cleared to zero, the motor has no rotational position signal asynchronous fault, and operates normally.

[0034] In some embodiments, when the number of error patterns detected within a 1ms time window exceeds 255, or the total number of error patterns accumulated during operation exceeds 5, the system will reset the Hall diff flag and trigger the sensor fault flag to indicate a serious signal anomaly. If the system identifies more than 12 consecutive correct signal patterns during continuous monitoring, it will automatically reset the error counter, thereby achieving state recovery and system self-correction. See the table below: like Figure 4As shown, the control flow of this invention is as follows: obtain the initial position of the motor and determine the validity of the position information; power on, the two sets of sensors send synchronization signals and complete synchronization within a determined time and number of synchronizations; if the incremental synchronization of the position signals of the two sets of sensors fails, degrade the operation (motor disabled or low speed operation); if the incremental synchronization of the position signals of the two sets of sensors succeeds, control the motor in closed-loop mode, determine the motor rotation direction, torque and rotation speed according to the motor position and the target position, determine the optimal way to reach the target lift, and continuously monitor the motor's following performance and error count; finally, stop the machine and return to the designated position.

[0035] In some technical solutions, the method for obtaining the actual rotational position of the motor includes: obtaining the initial position of the motor based on the current actual lift position of the helical eccentric shaft; and obtaining the actual lift position of the helical eccentric shaft driven by the motor rotation based on the rotation angle of the secondary magnetic wheel or the main magnetic wheel of the motor rotor, which is the actual rotational position of the motor.

[0036] The motor described in this application is used to drive a continuously variable valve lift mechanism; the rotor power output shaft of the motor is connected to a worm gear. Figure 6 This is a continuously variable valve lift (VVL) system, comprising a torsion spring 1, a limiting block 2, a valve mechanism 5, a valve rocker arm 8, a worm gear 4 (motor), and a hydraulic tappet 9. One end of the valve rocker arm 8 is pressed against the valve mechanism 5, and the other end is connected to the hydraulic tappet 9 via a ball joint. It also includes an intermediate camshaft 3 (a helical eccentric shaft) and a cam rocker arm 7. The cam rocker arm 7 includes a cam rocker arm end face located at its lower end, and a first cam rocker arm roller and a second cam rocker arm roller connected to the cam rocker arm 7. The end face of the cam rocker arm 7 contacts and engages with the valve rocker arm 8, the first cam rocker arm roller contacts and engages with the intermediate camshaft 3, and the second cam rocker arm roller contacts and engages with the cam 6. The torsion spring 1 is fixed to the limiting block 2 by bolt fasteners 10. An engine with this variable valve lift mechanism can continuously vary within the maximum valve lift range. The motor 4 drives the camshaft 3 (helical eccentric shaft) to rotate, the cam 6 pushes the cam rocker arm 7, the cam rocker arm 7 pushes the valve rocker arm 8, and the valve rocker arm 8 opens the engine valve.

[0037] In some embodiments, the worm gear 4 is a motor, and the intermediate camshaft 3 is a helical eccentric shaft. The threaded portion on the motor rotor can drive a maximum effective lift of 9mm through rotation. The motor drives the helical eccentric shaft to rotate; one rotation of the motor causes the helical eccentric shaft to rotate one tooth. One tooth rotation of the helical eccentric shaft increases or decreases its corresponding lift by one-tenth of a millimeter. Each one-tenth of a millimeter corresponds to one engine valve opening. The helical eccentric shaft has mechanical dead points at the maximum and minimum lift positions driven by the motor. It is easy to understand that the rotation center of the helical eccentric shaft is the rotation center of the turbine meshing with the worm gear; a cam is set on the rotation center shaft of the turbine meshing with the worm gear; the lift of the cam is the lift of the helical eccentric shaft.

[0038] During vehicle operation, the continuously variable valve lift mechanism is constantly working. Each time the engine valve opening is changed, the number of motor rotations can be calculated based on the historical rotation angle of the motor. The current actual lift position of the helical eccentric shaft is determined based on the number of motor rotations, and this current actual lift position of the helical eccentric shaft is used as the initial position for controlling the motor rotation each time. Once the initial position of the motor is determined, the actual lift position driven by the helical eccentric shaft can be continuously tracked and calculated based on the rotation angle and rotation speed of the secondary and primary magnetic wheels of the motor rotor. This achieves high-precision control of the target lift position of the helical eccentric shaft (i.e., valve lift).

[0039] In some technical solutions, the method of adjusting the actual rotation position of the motor to reach the target rotation position based on the difference between the actual rotation position and the target rotation position of the motor includes: the PID controller drives the motor to rotate to the target lift position of the helical eccentric shaft based on the difference between the actual lift position and the target lift position of the helical eccentric shaft, wherein the target lift position of the helical eccentric shaft is obtained according to a pre-calibrated target lift position lookup table.

[0040] After successfully achieving incremental synchronization of high- and low-resolution position signals, the motor control system immediately switches to closed-loop control mode. During this process, the system drives the rotor to rotate at a preset angle or step size by precisely controlling the sequence and timing of current switching in the motor windings. The controller first issues a command containing the target rotation direction and speed, and then accurately sets the motor's output torque by adjusting the current vector. The system's electronic commutation and high-precision angular position acquisition rely on real-time analysis of Hall signals: the rotor direction is determined based on the phase difference between the high-resolution Hall sensor and the signal, and a hardware counter counts the edges of these two signals. An interrupt is triggered at each commutation step (corresponding to a commutation magnetic field angle in 60° units), thereby sequentially sensing the three-phase phase signals W, V, and U of the motor from top to bottom and their corresponding commutation states. Due to the consideration of the leading characteristic of the rotation angle in actual control, the effective control accuracy is further improved to 30°, thus achieving smoother and more precise magnetic field orientation control. The system continuously monitors Hall signals, acquires key parameters such as the motor's actual position and speed in real time, and quickly compares these feedback values ​​with the control commands. The control core dynamically calculates and adjusts the required rotational speed based on the deviation between the target position and the actual position, positioning the drive motor to the target lift position with optimal response speed. Throughout operation, the system continuously monitors the status of the motor control mode and performs statistical analysis and diagnostics on the synchronization of Hall signals to ensure continuous and reliable control.

[0041] The motor speed is controlled by PWM (Pulse Width Modulation). The motor controller provides PWM waves to determine the switching frequency of the power transistors and the timing of converter commutation. By changing the pulse width, the average voltage of the motor is adjusted, thereby controlling the motor speed. For example, when the difference between the actual lift position and the target lift position of the helical eccentric shaft is small, requiring the motor to run at low speed, a PWM signal with a small duty cycle is output; when the difference between the actual lift position and the target lift position of the helical eccentric shaft is large, requiring the motor to run at high speed, a PWM signal with a large duty cycle is output.

[0042] By comparing the difference between the actual and target rotational positions of the motor in real time and dynamically adjusting the angle, torque, and speed, it can be understood that by controlling the torque output, speed, and running time, the rotational angle of the motor (rotation angle) is adjusted, which in turn controls the rotational angle of the worm gear and the lift of the cam, thus achieving valve lift control. This system enables fast and precise closed-loop control, ensuring that the motor's helical eccentric shaft reaches the target lift position with the optimal response path, thereby significantly improving control accuracy to the 0.1 mm level, enhancing the system's dynamic response capability, and effectively reducing vibration and noise. Simultaneously, this differential feedback-based adjustment mechanism improves operational stability and reliability, making it suitable for high-precision scenarios such as valve lift adjustment in electric vehicles, balancing efficiency and robustness.

[0043] like Figure 6 A continuously variable valve lift (VVL) system is described. When the drive motor 4 rotates one revolution, the corresponding camshaft 3 (helical eccentric shaft) rotates one tooth, causing its corresponding lift to increase or decrease by one-tenth of a millimeter. The corresponding engine valve opening is recorded, and a pre-calibrated target lift position lookup table is obtained. Based on the required engine valve opening, the target lift position of the helical eccentric shaft can be obtained by looking up the table. Based on the target lift position, the number of revolutions required for the motor to rotate can be obtained, realizing high-precision control of the engine valve opening by the motor.

[0044] Example 2 A smart control method for a permanent magnet synchronous brushless motor based on the system, comprising: The rotational position signal of the secondary magnetic wheel of the motor rotor is measured by a high-resolution position sensor, and the rotational position signal of the main magnetic wheel of the motor rotor is measured by a low-resolution sensor. The system detects whether the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed position signal increment synchronization within a set time. When the rotational position signal of the secondary magnetic wheel of the motor rotor and the rotational position signal of the main magnetic wheel of the motor rotor have completed position signal increment synchronization within a set time, the motor enters the closed-loop control operation mode. In the closed-loop control operation mode of the motor, the actual rotation position of the motor is determined based on the initial position of the motor, the rotation position signals of the secondary magnetic wheel of the motor rotor and the main magnetic wheel of the motor rotor, and the actual rotation position of the motor is adjusted according to the difference between the actual rotation position and the target rotation position of the motor to achieve the target rotation position of the motor.

[0045] In this embodiment, a motor is used to drive a continuously variable valve lift mechanism; the rotor power output shaft of the motor is connected to a worm gear; it can be understood that the intelligent control method of the permanent magnet synchronous brushless motor in this embodiment is a control method for a continuously variable valve lift mechanism; achieving precise control of valve lift.

[0046] Example 3 This invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of the method described in Embodiment 2. In one embodiment, the computer-readable storage medium is configured in an engine controller.

[0047] This invention can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented in whole or in part as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)).

[0048] It will be readily understood by those skilled in the art that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, substitutions, improvements, etc., made under the spirit and principles of the present invention are included within the protection scope of the present invention.

[0049] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. An intelligent control system for a permanent magnet synchronous brushless motor, characterized in that, It comprises: The sensor measurement module is used for measuring the rotation position signal of the motor rotor secondary magnetic wheel through a high-resolution position sensor and measuring the rotation position signal of the motor rotor primary magnetic wheel through a low-resolution sensor; The synchronous detection module is used for detecting whether the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel complete position signal increment synchronization within a set time, and when the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel complete position signal increment synchronization within the set time, the motor enters a closed-loop control operation mode; The closed-loop control module is used for determining the actual rotation position of the motor according to the initial position of the motor, the rotation position signals of the motor rotor secondary magnetic wheel and the motor rotor primary magnetic wheel in the closed-loop control operation mode of the motor, and adjusting the actual rotation position of the motor according to the difference between the actual rotation position of the motor and the target rotation position of the motor to reach the target rotation position of the motor.

2. An intelligent control system for a permanent magnet synchronous brushless motor, characterized in that, It also comprises: The synchronous fault detection module is used for continuously detecting whether the position signal increment between the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel remains synchronized in the closed-loop control mode of the motor, and when the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel are out of synchronization, recording the out-of-synchronization fault of the rotation position signal and performing a debouncing operation, otherwise the motor operates normally.

3. The intelligent control system of a permanent magnet synchronous brushless motor according to claim 1, characterized in that: The high-resolution position sensor and the low-resolution position sensor are both multiple, and the multiple high-resolution position sensors and the low-resolution position sensors are arranged at a set included angle.

4. The intelligent control system of a permanent magnet synchronous brushless motor according to claim 1, characterized in that: The method for detecting whether the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel complete position signal increment synchronization within a set time comprises: within the set time, when the position signal step increment between the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel exceeds a set step, the synchronization fails, otherwise the synchronization succeeds.

5. The intelligent control system of a permanent magnet synchronous brushless motor according to claim 4, characterized in that: When the position signal step between the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel fails multiple times within the set time, the synchronization is restarted until the synchronization succeeds.

6. The intelligent control system of a permanent magnet synchronous brushless motor according to claim 2 or 4, characterized in that: The method for recording the out-of-sync fault and performing the de-bouncing operation when the out-of-sync fault occurs between the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel comprises: in a fault detection period in the motor closed-loop control mode, when the number of times that the position signal increment between the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel is out of sync exceeds a first set number threshold, marking an out-of-sync fault identifier of the rotation position signal, when the number of times that the out-of-sync fault identifier of the rotation position signal appears continuously exceeds a second set number threshold, recording an out-of-sync fault of the rotation position signal, and performing the shutdown or degraded operation of the motor; if the number of times that the out-of-sync fault identifier of the rotation position signal appears continuously exceeds the second set number threshold before the number of times that the out-of-sync fault identifier of the rotation position signal appears continuously exceeds the second set number threshold in the continuous multiple fault detection periods, the out-of-sync fault identifier count is cleared, the motor has no out-of-sync fault of the rotation position signal, and the motor operates normally.

7. The intelligent control system of a permanent magnet synchronous brushless motor according to claim 1, characterized in that: The method for obtaining the actual rotation position of the motor comprises: obtaining the initial position of the motor based on the current actual lift position of the helical eccentric shaft, and obtaining the actual lift position of the helical eccentric shaft driven by the rotation of the motor rotor as the actual rotation position of the motor based on the initial position of the motor, the rotation angle of the motor rotor secondary magnetic wheel or the motor rotor primary magnetic wheel.

8. The intelligent control system of a permanent magnet synchronous brushless motor according to claim 1 or 7, characterized in that: The method for adjusting the actual rotation position of the motor to reach the target rotation position of the motor according to the difference between the actual rotation position of the motor and the target rotation position of the motor comprises: a PID regulator drives the motor to rotate to reach the target lift position of the helical eccentric shaft according to the difference between the actual lift position of the helical eccentric shaft and the target lift position of the helical eccentric shaft, and the target lift position of the helical eccentric shaft is obtained according to a pre-marked target lift position lookup table.

9. An intelligent control method of a permanent magnet synchronous brushless motor based on the system of claim 1, characterized in that, The method comprises: measuring the rotation position signal of the motor rotor secondary magnetic wheel by a high-resolution position sensor, and measuring the rotation position signal of the motor rotor primary magnetic wheel by a low-resolution sensor; detecting whether the position signal increment between the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel is synchronized within a set time, and when the position signal increment between the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel is synchronized within the set time, the motor enters the closed-loop control operation mode; in the closed-loop control operation mode of the motor, determining the actual rotation position of the motor according to the initial position of the motor, the rotation position signal of the motor rotor secondary magnetic wheel and the rotation position signal of the motor rotor primary magnetic wheel, and adjusting the actual rotation position of the motor to reach the target rotation position of the motor according to the difference between the actual rotation position of the motor and the target rotation position of the motor.

10. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to realize the steps of the method in claim 9.

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