Vehicle-mounted brushless motor control system and method

Abstract

The invention discloses a vehicle-mounted brushless motor control system and method, and relates to the technical field of automobile electronic control, and the method comprises the steps: carrying out the initialization after power-on, including working frequency configuration, time reference setting and interruption mechanism establishment, and carrying out the initial safety setting of a drive output module; according to the invention, working frequency setting, time reference synchronization and interruption mechanism establishment are sequentially completed through the main control module in a power-on stage, and in combination with safety configuration of a three-phase bridge arm driving loop, a safe and controllable driving output state can be entered at the starting moment; according to the method, a double-loop closed-loop structure formed by outer loop speed regulation and inner loop current regulation is adopted in the operation stage, the driving control quantity can be quickly and accurately generated under target instruction change and load disturbance, continuous and stable regulation of motor output is achieved, the operation smoothness, dynamic response performance and control precision of the vehicle-mounted brushless motor are improved, and the vehicle-mounted brushless motor control method is suitable for large-scale popularization and application. Therefore, the stability of the whole vehicle driving system is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automotive electronic control technology, in particular to a vehicle-mounted brushless motor control system and method. BACKGROUND

[0002] A brushless DC motor is a kind of motor structure that realizes electromagnetic energy conversion in an electronic commutation manner. Compared with a traditional brush DC motor, the brushless DC motor cancels the mechanical commutator and carbon brush assembly in structure, adopts a stator winding and a permanent magnet rotor to work together, and realizes electronic commutation through a position sensor or a position estimation algorithm, thereby obtaining higher efficiency, reliability and service life. The brushless motor is usually composed of a stator core, a three-phase winding, a permanent magnet rotor and a power drive circuit. The drive system collects rotor positions or calculates electrical angles by using a back electromotive force algorithm, and then controls the conduction combination of the three-phase bridge arm according to the corresponding commutation logic, so that the motor generates a continuous rotating magnetic field in the full speed range, and realizes electromagnetic torque output. The traditional scheme is prone to overcurrent and overtemperature under high-voltage input and transient load, which leads to a decline in motor control performance and even causes system failure. In view of the above technical defects, a solution is proposed. SUMMARY

[0003] In view of the deficiencies of the prior art, the present application provides a vehicle-mounted brushless motor control system and method.

[0004] To achieve the above purpose, the present application is implemented by the following technical scheme: a vehicle-mounted brushless motor control system and method, comprising: S1, initialization after power-on, including work frequency configuration, time reference setting and interrupt mechanism establishment, and performing initial safety setting on the drive output module; the initial safety configuration is performed through the three-phase bridge arm drive loop, and the initial output is set to a safe state; S2, the analog-to-digital conversion module collects voltage, current and position signals related to motor operation; the collected operating quantities are pretreated by a filtering algorithm before entering the control core, for suppressing transient noise and disturbance; S3, open-loop positioning and acceleration process is executed, the motor is accelerated from static to closed-loop condition through a preset drive sequence and output climb curve, and a smooth transition strategy is executed to suppress operation impact; after entering operation, the drive control quantity is formed through the joint adjustment mechanism of the outer loop and the inner loop; the outer loop calculates the deviation of the target instruction and the actual operating quantity to form a current reference quantity, and the inner loop generates a modulation control instruction according to the deviation of the actual operating quantity and the reference quantity and converts it into a drive output signal; S4, during operation, orderly mode switching is performed between the running mode, standby mode and fault mode according to external requests or internal states; S5, monitoring voltage, current, temperature and external signal state, identifying overcurrent, overtemperature, power abnormal fault events through multi-level decision mechanism; when detecting any abnormal signal, triggering shutdown strategy according to fault level, including closing drive output, shutting down enable signal and executing controlled shutdown.

[0005] The initial safety setting performed on the drive output includes: completing the clock source CLK frequency configuration, timer TIM period setting and interrupt control unit INT initialization by the microcontroller MCU in the master module in the initialization sequence; The microcontroller MCU sets the carrier frequency and dead zone time DZT for the three-phase bridge arm drive circuit respectively, forces the three-phase initial duty ratio DUT to zero; the analog-digital conversion module enables the bus voltage sampling channel, motor phase current sampling channel, bus current sampling channel and power device temperature sampling channel, and sets the sampling trigger source as the update event of the timer TIM; the microcontroller MCU completes the mapping configuration of external signals through the general input-output interface GIO, including configuring the Hall signal POS as the trigger input, configuring the overtemperature comparison signal OTC and overcurrent comparison signal OCC as the fast interrupt input, and configuring the external enable signal ENA as the state reading input.

[0006] The analog-digital conversion module collects the bus voltage, bus current and three-phase phase current signals according to the synchronous update event triggered by the timer TIM, and calculates the corresponding motor electrical angle position and actual speed through the rising or falling edge capture event of the Hall signal POS; the voltage, current and speed signals are subjected to the moving average filtering algorithm executed by the microcontroller MCU for suppressing high-frequency switching noise and the first-order low-pass filtering algorithm for weakening transient electromagnetic disturbance before entering the control link, to obtain the motor running quantity; the microcontroller MCU compares the bus voltage with the under-voltage threshold and the over-voltage threshold, and determines the power state trend through the trend discrimination rule of continuous multiple periods.

[0007] In the closed-loop control stage, the microcontroller MCU executes the double-loop regulation process of the speed loop and the current loop, including: calculating the difference between the target speed and the actual speed as the speed error and inputting it to the speed proportional-integral regulator, and outputting the current given value according to the amplitude and change trend of the speed error; The current given value and the actual motor current are differentiated to obtain the current error, which is input to the current proportional-integral regulator to generate the voltage side modulation control quantity; the voltage modulation control quantity is mapped to the duty ratio instruction of the three-phase drive by the microcontroller MCU according to the inverter modulation index conversion rule, and the duty ratio instruction is output to the three-phase bridge arm drive circuit.

[0008] The microcontroller MCU executes the open-loop pre-positioning and acceleration control, including: S21, applying three-phase excitation according to a commutation table by a positioning unit in a stationary state of the motor; S22, gradually increasing the duty cycle of the three-phase drive according to a duty cycle climbing curve by an open-loop acceleration unit; S23, periodically detecting the actual speed during the acceleration process, and when it is detected that the actual speed reaches a closed-loop switching threshold, closing the open-loop drive logic and switching to a double-loop closed-loop control mode, and the speed loop and the current loop are simultaneously put into operation; S24, performing a duty cycle smooth transition strategy to avoid torque pulsation during the switching process, and aligning the phase according to the commutation table and the actual electrical angle.

[0009] Performing an orderly switching between the running mode RUN, standby mode STB and fault mode FLT, including: when the mode management module receives a standby mode instruction or the internal state machine meets the standby condition, performing a step-by-step decrease on the target speed instruction, so that the target speed is smoothly decreased from the current value to zero; the microcontroller MCU turns off the enable signal of the drive module and closes all outputs and control logic except power supply monitoring; When an external wake-up signal or a task request from the upper computer is detected, the microcontroller MCU exits the standby mode, re-executes the initial safety setting, and after completion, restores to the running mode.

[0010] The fault protection module performs multi-stage fault processing, including: The phase current and bus current are continuously sampled through a sampling resistor and an amplification circuit, and when any of the sampled currents exceeds the current threshold, an overcurrent signal is generated by the fault protection module to close all drive outputs of the pulse width modulation module PWM; The temperature of the power device is collected by an NTC temperature sensor, and when the temperature exceeds the temperature threshold, an over-temperature signal is output, and the drive output and the enable signal are closed according to the overcurrent processing strategy; The bus voltage is continuously sampled and compared with the under-voltage threshold and the over-voltage threshold, and when the bus voltage is in the under-voltage or over-voltage interval for a plurality of control periods, it is identified as a power supply abnormality, and a controlled shutdown is performed in the order of reducing the duty cycle, closing the pulse width modulation module PWM and turning off the drive module enable signal.

[0011] A vehicle-mounted brushless motor control system, comprising: A main control module for constructing a basic control environment after power-on, including completing work frequency setting, time reference synchronization and interrupt mechanism establishment, and performing initial safety setting on the drive output; An analog-to-digital conversion module for acquiring voltage, current and position type operating quantities from the motor, and suppressing high-frequency noise and transient disturbance through a preprocessing mechanism based on a filter model; A mode management module for performing an orderly switch between the running, standby and failure modes according to external requests and internal states; A failure protection module for monitoring voltage, current, temperature and external protection signals, identifying overcurrent, overtemperature, power supply abnormality through a multi-stage decision mechanism, and triggering corresponding protection strategies according to the failure level.

[0012] The application provides a vehicle-mounted brushless motor control system and method. The application sets the working frequency, synchronizes the time reference and establishes the interrupt mechanism in sequence in the power-on stage through the master control module, and combines the safety configuration of the three-phase bridge arm driving circuit to enter a safe and controllable driving output state at the starting moment; in the running stage, a double-loop closed-loop structure formed by the outer loop speed regulation and the inner loop current regulation is adopted to quickly and accurately generate the driving control amount under the target instruction change and load disturbance, so that the continuous and stable regulation of the motor output is realized, the running smoothness, dynamic response performance and control accuracy of the vehicle-mounted brushless motor are improved, and the stability of the vehicle driving system is improved. The application periodically monitors the key physical quantities in the motor running process through the failure protection module, including voltage, current, temperature and external protection signals, and identifies overcurrent, overtemperature and power supply abnormality and other risk events based on a multi-stage decision rule; the driving output is closed, the driving enable signal is turned off and the controlled shutdown is performed in sequence according to the preset shutdown strategy, so that the failure risk of the driving system under abnormal working conditions is effectively reduced, the running safety of the vehicle-mounted brushless motor control system is significantly improved, the reliability of the vehicle power system is ensured, and potential safety accidents caused by motor failure are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is a schematic diagram of the principle framework of the application; Figure 2 It is a schematic diagram of the principle system mechanism of the application. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0015] Please refer to Figure 1 The application provides a vehicle-mounted brushless motor control system and method, which comprises: S1, initialization after power on, including work frequency configuration, time reference setting and interrupt mechanism establishment, and initial safety setting for driving output module; initial safety configuration is performed through three-phase bridge arm driving circuit to place initial output in safe state; S2, analog-digital conversion module collects voltage, current and position related signals of motor operation; collected operating quantities are preprocessed through filtering algorithm before entering control core to suppress transient noise and disturbance; S3, open-loop positioning and acceleration process is executed to realize acceleration of motor from static state to closed-loop condition through preset driving sequence and output climb curve, and smooth transition strategy is executed to suppress operation impact; after entering operation, driving control quantity is formed through joint adjustment mechanism of outer loop and inner loop; outer loop calculates deviation of target instruction and actual operating quantity to form current reference quantity, and inner loop generates modulation control instruction according to deviation of actual operating quantity and reference quantity and converts it into driving output signal; S4, during operation, orderly mode switching is performed between running mode, standby mode and fault mode according to external request or internal state; S5, voltage, current, temperature and external signal state are monitored, overcurrent, overtemperature, power abnormal fault events are identified through multi-stage judgment mechanism; when any abnormal signal is detected, stop strategy is triggered according to fault level, including closing driving output, turning off enable signal and executing controlled stop.

[0016] The initial safety setting for driving output includes: the microcontroller MCU in the main control module completes the frequency configuration of clock source CLK, the period setting of timer TIM and the initialization of interrupt control unit INT in initialization order; The microcontroller MCU sets the carrier frequency and dead zone time DZT of the three-phase bridge arm driving circuit respectively, and forces the initial duty ratio DUT of three phases to zero; the analog-digital conversion module enables the bus voltage sampling channel, motor phase current sampling channel, bus current sampling channel and power device temperature sampling channel, and sets the sampling trigger source as the update event of timer TIM; the microcontroller MCU completes the mapping configuration of external signals through general input and output interface GIO, including configuring Hall signal POS as edge trigger input, configuring overtemperature comparison signal OTC and overcurrent comparison signal OCC as fast interrupt input, and configuring external enable signal ENA as state reading input.

[0017] Specifically, after power-on, the microcontroller MCU executes the construction of the underlying control environment in a predetermined initialization sequence, first completes the clock source CLK frequency configuration to establish the unified main running frequency within the system; then sets the period of the timer TIM to maintain strict consistency with the subsequent sampling, modulation and control tasks; and synchronously completes the initialization of the interrupt control unit INT, including priority configuration, interrupt vector table update and key interrupt source enable, so that the system has a predictable time trigger mechanism.

[0018] After completing the basic control environment configuration, the microcontroller MCU performs safe initialization of the modulation parameters of the three-phase bridge arm drive circuit, specifically including setting the carrier frequency, dead time DZT and other basic PWM modulation parameters for the three-phase bridge arm, and forcibly setting the initial duty ratio DUT of all three-phase drive channels to zero to ensure that there is no misdirecting, cross-conducting or unintended drive output during initialization, thereby realizing safe startup of the drive link.

[0019] Subsequently, the analog-to-digital conversion module ADC is started and sequentially opens the bus voltage sampling channel, motor phase current sampling channel, bus current sampling channel and power device temperature sampling channel, and configures the sampling trigger source of the ADC as the update event of the timer TIM, so that all voltage, current and temperature sampling tasks are strictly synchronized with the PWM modulation period, realizing periodic consistent collection of operating quantities and avoiding data distortion caused by sampling phase drift.

[0020] The analog-to-digital conversion module collects bus voltage, bus current and three-phase phase current signals according to the synchronous update event triggered by the timer TIM, and calculates the corresponding motor electrical angle position and actual speed through the rising or falling edge capture event of the Hall signal POS; the voltage, current and speed signals are subjected to a sliding average filtering algorithm for suppressing high-frequency switching noise and a first-order low-pass filtering algorithm for weakening transient electromagnetic disturbance before entering the control loop, obtaining motor operating quantities; the microcontroller MCU compares the bus voltage with the under-voltage threshold and the over-voltage threshold, and determines the power supply state trend through continuous multi-period trend discrimination rules.

[0021] In the closed-loop control phase, the microcontroller MCU executes the double-loop regulation process of the speed loop and the current loop, including: calculating the difference between the target speed and the actual speed as the speed error and inputting it to the speed proportional integral regulator, and outputting the current given value according to the amplitude and change trend of the speed error; The current error is obtained by differentiating the current given value and the actual current of the motor, and the current error is input to a current proportional integral regulator to generate a voltage side modulation control quantity; the voltage modulation control quantity is mapped to a duty cycle instruction of three-phase driving by a microcontroller MCU according to an inverter modulation index conversion rule, and the duty cycle instruction is output to a three-phase bridge arm driving circuit.

[0022] The microcontroller MCU performs open-loop positioning and acceleration control, including: S21, a pre-positioning unit applies three-phase excitation according to a fixed phase sequence in a motor static state according to a commutation table; S22, an open-loop acceleration unit gradually increases the duty cycle of three-phase driving according to a duty cycle climbing curve; S23, during the acceleration process, the actual speed is periodically detected, and when the actual speed is detected to reach the closed-loop switching threshold, the open-loop driving logic is turned off and the double-loop closed-loop control mode is switched in, and the speed loop and the current loop are simultaneously put into work; S24, during the switching process, a duty cycle smooth transition strategy is performed to avoid torque pulsation, and phase alignment is performed according to the commutation table and the actual electrical angle.

[0023] In a vehicle-mounted brushless motor control method, a microcontroller MCU realizes smooth acceleration of the motor from a static state to a closed-loop condition through open-loop pre-positioning and acceleration control logic, and the specific implementation is as follows: in the initial static state of the motor and before the motor has position resolution capability, the microcontroller MCU calls a pre-positioning unit, applies three-phase excitation to the motor stator winding according to a fixed phase sequence according to a preset commutation table, to establish a stable flux linkage direction, realize pre-locking of the motor rotor position, and make the rotor have a controllable initial electrical angle position.

[0024] After completing the pre-positioning, the microcontroller MCU activates an open-loop acceleration unit, gradually increases the output duty cycle of the three-phase bridge arm driving circuit according to a preset duty cycle climbing curve, and drives three-phase excitation according to a fixed commutation period, to realize initial acceleration of the motor without the participation of the speed closed loop, so that the motor enters the low-speed controllable interval from the static state.

[0025] During the open-loop acceleration process, the microcontroller MCU collects and calculates the actual speed at a fixed detection period, and when the actual speed is detected to reach the set closed-loop switching threshold, it is considered that the motor has reliable speed feedback conditions, at this time the MCU closes the open-loop driving logic, stops the open-loop mode of fixed period commutation, and then immediately switches to the double-loop closed-loop control mode with the participation of the speed loop and the current loop, to realize disturbance-free switching from open-loop acceleration to closed-loop regulation.

[0026] In the process of performing closed-loop switching, the microcontroller MCU further enables the duty cycle smooth transition strategy, performs slope limiting transition and gradual mapping processing on the difference between the open-loop end duty cycle and the closed-loop initial duty cycle, to avoid electromagnetic force pulsation or torque impact caused by sudden change of duty cycle. At the same time, the MCU performs phase alignment combined with the commutation table and the actual electrical angle obtained through the Hall sensor, to ensure that the electrical angle reference of the closed-loop control and the actual flux position of the motor remain consistent, thereby improving switching stability and torque continuity.

[0027] Sequential switching is performed between the running mode RUN, standby mode STB and fault mode FLT, including: when the mode management module receives a standby mode instruction or the internal state machine meets the standby condition, gradually decreasing the target speed instruction, so that the target speed is smoothly reduced from the current value to zero; the microcontroller MCU turns off the enable signal of the drive module and closes all outputs and control logic except power supply monitoring; When an external wake-up signal or a task request of the upper computer is detected, the microcontroller MCU exits the standby mode, re-executes the initial safety setting, and after completion, restores to the running mode.

[0028] Beneficial effects: The application can enter a safe and controllable driving output state at the starting moment by completing the working frequency setting, time reference synchronization and interrupt mechanism establishment in the power-on phase in combination with the safety configuration of the three-phase bridge arm driving circuit; in the running phase, a double-loop closed-loop structure formed by the outer loop speed regulation and the inner loop current regulation can quickly and accurately generate a driving control amount under the change of the target instruction and the load disturbance, so that continuous and stable regulation of the motor output is realized, which improves the running smoothness, dynamic response performance and control accuracy of the vehicle-mounted brushless motor, thereby improving the stability of the vehicle driving system.

[0029] The fault protection module performs multi-stage fault processing, including: The phase current and bus current are continuously sampled through the sampling resistor and amplification circuit, and when any sampling current exceeds the current threshold, an overcurrent signal is generated by the fault protection module to close all driving outputs of the pulse width modulation module PWM; The temperature of the power device is collected through the NTC temperature sensor, and when the temperature exceeds the temperature threshold, an over-temperature signal is output, and the driving output and the enable signal are closed according to the overcurrent processing strategy; The bus voltage is continuously sampled and judged with the under-voltage threshold and the over-voltage threshold, and when the bus voltage is in the under-voltage or over-voltage interval for a plurality of control periods, it is identified as a power supply anomaly, and a controlled shutdown is performed in the order of reducing the duty cycle, closing the pulse width modulation module PWM and turning off the enable signal of the drive module.

[0030] Specifically, the fault protection module performs comprehensive fault processing on current, temperature and power state through a multi-level monitoring mechanism, and the specific implementation is as follows: during system operation, the fault protection module first cooperates with a current amplification circuit through a current sampling resistor arranged in a three-phase drive loop and a bus side to continuously sample phase current and bus current, a microcontroller MCU reads the detection voltage output by the current amplification circuit in real time and converts to obtain the actual current value. When any phase current or bus current is detected to exceed the preset current threshold, the fault protection module immediately generates an overcurrent signal, and in the same control cycle, the MCU performs a fast protection action, including turning off all drive outputs of the pulse width modulation module PWM and closing the enable signal of the drive module, thereby quickly cutting off the output path and preventing the power device from being further damaged.

[0031] In terms of temperature monitoring, the fault protection module continuously collects the temperature of the power device through the NTC temperature sensor arranged near the power driver, and the microcontroller MCU compares the temperature sampling result with the temperature threshold, and immediately generates an over-temperature signal when the temperature is detected to exceed the set threshold, and closes the three-phase drive output and the drive enable signal according to the same shutdown strategy as the overcurrent fault, so that the system enters the protection shutdown state. At the same time, record the fault type and temperature information for subsequent diagnostic analysis.

[0032] In terms of power monitoring, the fault protection module uses the analog-to-digital conversion module ADC to continuously sample the bus voltage, and the MCU determines the interval of the sampled bus voltage with the under-voltage threshold and the over-voltage threshold, and uses a continuous multi-cycle trend verification mechanism to confirm whether the power is in an abnormal interval. When the bus voltage is continuously lower than the under-voltage threshold or higher than the over-voltage threshold in multiple control cycles, the system determines that the power is abnormal. At this time, the fault protection module sequentially executes the reduction of the three-phase drive duty cycle, the closing of the PWM drive output and the shutdown of the drive module enable signal according to the controlled shutdown sequence, to ensure that the motor stops running in a controlled manner under abnormal power supply conditions, avoiding further damage caused by excessively high or low voltage.

[0033] Advantages: The present application periodically monitors key physical quantities during motor operation through the fault protection module, including voltage, current, temperature and external protection signals, and identifies overcurrent, overtemperature and power abnormality and other risk events based on multi-level judgment rules; according to the preset shutdown strategy, the drive output is closed, the drive enable signal is turned off and the controlled shutdown is executed, which effectively reduces the failure risk of the drive system under abnormal working conditions, significantly improves the operation safety of the vehicle brushless motor control system, thereby ensuring the reliability of the vehicle power system and reducing potential safety accidents caused by motor failure.

[0034] A vehicle brushless motor control system comprises: A master module for performing construction of a basic control environment after power-up, including completion of working frequency setting, time reference synchronization, and establishment of an interrupt mechanism, and performing initial safety setting on a drive output; An analog-to-digital conversion module for acquiring voltage, current, and position type operating quantities from the motor, and suppressing high-frequency noise and transient disturbances through a pre-processing mechanism based on a filter model; A mode management module for performing orderly switching between a running mode, a standby mode, and a fault mode according to external requests and internal states; A fault protection module for monitoring voltage, current, temperature, and external protection signals, identifying overcurrent, overtemperature, power supply abnormalities through a multi-level decision mechanism, and triggering corresponding protection strategies according to fault levels.

[0035] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented by software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the flow or function according to the embodiments of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another, for example, the computer instructions can be transferred from one website, computer, server, or data center to another via a wired network or wireless network. The computer-readable storage medium can be any available medium accessible by a computer or a data storage device such as a server, data center, etc. containing one or more available medium collections. 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. The semiconductor medium can be a solid-state disk.

[0036] Some of the data in the above formulas are dimensionless for numerical calculation, and the contents not described in detail in the specification are all prior art known to those skilled in the art.

[0037] The above embodiments are only used to illustrate the technical method of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical method of the present application.

Claims

1. A method for controlling an on-board brushless motor, characterized in that, include: S1. After power-on, initialization is performed, including operating frequency configuration, time base setting and interrupt mechanism establishment, and initial safety settings are performed on the drive output module; the initial safety configuration is performed through the three-phase bridge arm drive circuit to set the initial output to a safe state; S2, the analog-to-digital conversion module collects voltage, current and position signals related to motor operation; the collected operating signals are preprocessed by a filtering algorithm before entering the control core to suppress transient noise and disturbances; S3. Execute the open-loop positioning and acceleration process. Through the preset drive sequence and output climbing curve, the motor is accelerated from a standstill to a state where it meets the closed-loop conditions. A smooth transition strategy is executed to suppress the running shock. After entering operation, the drive control quantity is formed through the joint adjustment mechanism of the outer loop and the inner loop. The outer loop calculates the deviation between the target command and the actual running quantity to form the current reference quantity. The inner loop generates the modulation control command based on the deviation between the actual running quantity and the reference quantity and converts it into a drive output signal. S4. During operation, the system performs orderly mode switching between operating mode, standby mode, and fault mode based on external requests or internal status. S5 monitors voltage, current, temperature and external signal status, and identifies overcurrent, overtemperature and power supply abnormality fault events through a multi-level judgment mechanism; when any abnormal signal is detected, it triggers a shutdown strategy according to the fault level, including shutting down the drive output, turning off the enable signal and executing a controlled shutdown.

2. The vehicle-mounted brushless motor control method according to claim 1, characterized in that, The initial safety settings for the drive output include: the microcontroller (MCU) in the main control module performs the main frequency configuration of the clock source CLK, the period setting of the timer TIM, and the initialization of the interrupt control unit INT in the initialization sequence. The microcontroller (MCU) sets the carrier frequency and dead time (DZT) for the three-phase bridge arm drive circuits respectively, and forces the initial duty cycle (DUT) of the three phases to zero. The analog-to-digital converter (ADC) enables the bus voltage sampling channel, motor phase current sampling channel, bus current sampling channel, and power device temperature sampling channel, and sets the sampling trigger source to the update event of the timer (TIM). The MCU completes the mapping configuration of external signals through the general-purpose input / output interface (GIO), including configuring the Hall signal (POS) as an edge-triggered input, configuring the over-temperature comparison signal (OTC) and the over-current comparison signal (OCC) as fast interrupt inputs, and configuring the external enable signal (ENA) as a status read input.

3. The vehicle-mounted brushless motor control method according to claim 1, characterized in that, The analog-to-digital conversion module acquires bus voltage, bus current, and three-phase phase current signals according to the synchronous update event triggered by timer TIM, and calculates the corresponding motor electrical angle position and actual speed by capturing the event through the rising or falling edge of the Hall signal POS. Before entering the control loop, the voltage, current, and speed signals are processed by the microcontroller (MCU) using a moving average filtering algorithm to suppress high-frequency switching noise and a first-order low-pass filtering algorithm to weaken transient electromagnetic disturbances, thus obtaining the motor operating parameters. The microcontroller (MCU) compares the bus voltage with the undervoltage and overvoltage thresholds within a range, and determines the power supply state trend through a trend discrimination rule over multiple consecutive cycles.

4. The vehicle-mounted brushless motor control method according to claim 2, characterized in that, During the closed-loop control phase, the microcontroller (MCU) executes a dual-loop regulation process involving speed and current loops, including: calculating the difference between the target speed and the actual speed as the speed error and inputting it to the speed proportional-integral regulator; and outputting the current setpoint based on the magnitude and trend of the speed error. The current error is obtained by differentiating the current setpoint from the actual motor current. The current error is then input to the current proportional-integral regulator to generate the voltage-side modulation control quantity. The voltage modulation control quantity is mapped by the microcontroller (MCU) into the duty cycle command for the three-phase drive according to the inverter modulation index conversion rule. The duty cycle command is then output to the three-phase bridge arm drive circuit.

5. The vehicle-mounted brushless motor control method according to claim 2, characterized in that, The microcontroller (MCU) performs open-loop pre-positioning and acceleration control, including: S21. The prepositioning unit applies three-phase excitation according to the commutation table in a fixed phase sequence when the motor is stationary. S22. The three-phase drive duty cycle is gradually increased by the open-loop acceleration unit according to the duty cycle ramp curve; S23. During acceleration, the actual speed is periodically detected. When the actual speed reaches the closed-loop switching threshold, the open-loop drive logic is turned off and the dual-loop closed-loop control mode is switched on, with the speed loop and current loop working simultaneously. S24. During the switching process, a duty cycle smooth transition strategy is implemented to avoid torque pulsation, and phase alignment is performed according to the commutation table and the actual electrical angle.

6. The vehicle-mounted brushless motor control method according to claim 1, characterized in that, The system performs orderly switching between the RUN mode, STB standby mode, and FLT fault mode, including: when the mode management module receives a standby mode command or the internal state machine meets the standby conditions, it executes a step-by-step decrease on the target speed command, so that the target speed smoothly decreases from the current value to zero; the microcontroller MCU shuts down the enable signal of the drive module and turns off all output and control logic except for power monitoring. When an external wake-up signal or a task request from the host computer is detected, the microcontroller (MCU) exits standby mode, re-executes the initial security settings, and then returns to running mode.

7. The vehicle-mounted brushless motor control method according to claim 1, characterized in that, The fault protection module performs multi-level fault handling, including: The phase current and bus current are continuously sampled by sampling resistors and amplification circuits. When any sampled current exceeds the current threshold, the fault protection module generates an overcurrent signal and shuts down all drive outputs of the pulse width modulation module (PWM). The power device temperature is collected by an NTC temperature sensor. When the temperature exceeds the temperature threshold, an over-temperature signal is output, and the drive output and enable signal are turned off according to the overcurrent handling strategy. The bus voltage is continuously sampled and compared with the undervoltage and overvoltage thresholds. When the bus voltage is in the undervoltage or overvoltage range for multiple consecutive control cycles, it is identified as a power supply abnormality, and controlled shutdown is performed in the order of reducing the duty cycle, turning off the pulse width modulation module (PWM), and turning off the drive module enable signal.

8. A vehicle-mounted brushless motor control system, characterized in that, include: The main control module is used to build the basic control environment after power-on, including setting the working frequency, synchronizing the time base, and establishing the interrupt mechanism, and to perform initial safety settings on the drive output. The analog-to-digital conversion module is used to acquire voltage, current and position-related operating quantities from the motor, and suppresses high-frequency noise and transient disturbances through a preprocessing mechanism based on a filtering model. The mode management module is used to perform orderly switching between running, standby, and fault modes based on external requests and internal status. The fault protection module is used to monitor voltage, current, temperature and external protection signals. It identifies overcurrent, overtemperature and power supply abnormalities through a multi-level judgment mechanism and triggers corresponding protection strategies according to the fault level.

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