A motor puller servo drive control system and method

Abstract

The application relates to a motor puller servo drive control system and method, which comprises a master control MCU, an AC input rectification filter circuit connected with the master control MCU, a switching power supply circuit, a double-path IPM inverter drive module, a double-path three-phase current detection circuit and a double-path SPI absolute value encoder interface. The application solves the technical problems of poor torque control precision, lack of protection mechanism and insufficient double-motor independent control capability of the existing puller controller; realizes independent position, speed and torque vector control of two servo motors, simultaneously builds a multiple software and hardware cooperative protection mechanism, and improves the operation safety, control precision and response speed of the intelligent puller.

Description

Technical Field

[0001] This invention relates to the field of motor control technology for fitness equipment, specifically to a servo drive control system and method for a motor tensioner. Background Technology

[0002] Traditional resistance gauges typically use mechanical counterweights or cylinders / magnetic powder brakes to provide resistance. Their control circuits are relatively simple, usually including a power module, a main control MCU (often an 8-bit or 16-bit microcontroller), a motor drive module (using a DC brushed motor with single-tube chopper speed control, or a BLDC motor with six discrete MOSFETs and a pre-drive chip for six-step commutation control), a simple speed or position feedback module (Hall effect sensor or photoelectric encoder), and an operation display panel. Some devices use PLCs and servo drivers for resistance control, but these are bulkier and more expensive. Current detection only monitors the total bus current for overcurrent protection, without independent three-phase acquisition, making precise torque control impossible. The control modes are limited, providing only basic resistance adjustment and lacking multi-mode switching capabilities.

[0003] The existing controller only has simple overcurrent and overtemperature protection, lacking a systematic multi-layered hardware and software collaborative protection mechanism. Specifically, it lacks independent three-phase current detection, making it unable to identify faults such as phase loss, abnormal three-phase bias current, or excessive three-phase sampling current; it lacks comprehensive protection from the IPM module (such as FO fault signal processing); it lacks real-time bus voltage monitoring and overvoltage protection; it lacks validity verification of encoder signals; and it lacks real-time monitoring of motor winding temperature. When these abnormalities occur, the system cannot identify and respond in a timely manner, easily leading to damage to power devices or the motor, resulting in insufficient system reliability. Summary of the Invention

[0004] This invention provides a servo drive control system and method for a motor-driven tension controller, aiming to solve the technical problems of poor torque control accuracy, lack of protection mechanisms, and insufficient independent control capability of dual motors in existing tension controllers; it realizes independent position, speed, and torque vector control of two servo motors, and at the same time builds multiple software and hardware collaborative protection mechanisms to improve the operational safety, control accuracy, and response speed of the intelligent tension controller.

[0005] To achieve the above objectives, the present invention provides a servo drive control system for a motor tensioner, comprising: a main control MCU, an AC input rectifier and filter circuit, a switching power supply circuit, a dual-channel IPM inverter drive module, a dual-channel three-phase current detection circuit, and a dual-channel SPI absolute encoder interface connected to the main control MCU.

[0006] The AC input rectifier and filter circuit is used to convert AC mains power into DC bus voltage; the switching power supply circuit is electrically connected to the AC input rectifier and filter circuit, and outputs multiple low-voltage power supplies to power various components of the system.

[0007] The dual-channel IPM inverter drive module drives two servo motors respectively; the dual-channel three-phase current detection circuit collects the two-phase current signals of the corresponding servo motors and sends them to the main control MCU; the dual-channel SPI absolute encoder interface obtains the rotor angle and speed feedback signals of the two servo motors.

[0008] The main control MCU is equipped with a field-oriented FOC algorithm module and an SVPWM modulation module. It is used to generate six PWM signals to drive the IPM inverter to a three-phase sinusoidal voltage to drive the servo motor according to the position control mode, speed control mode, or torque control mode. Based on the feedback of the dual-channel three-phase current detection circuit and the dual-channel SPI absolute encoder interface, vector closed-loop and SVPWM modulation are performed to realize independent position closed-loop control, speed closed-loop control, and torque closed-loop control of the two servo motors.

[0009] A further technical solution of the present invention is that the dual-channel SPI absolute encoder interface is also used to acquire the rotor angle and speed of each servo motor in real time, the three-phase current detection circuit is also used to collect the two-phase current of each servo motor and calculate the third-phase current, and the MCU is also used to convert the third-phase current through Clarke transformation and Park transformation to obtain the quadrature-axis current Iq and direct-axis current Id in the rotating coordinate system, wherein the quadrature-axis current Iq is used for servo torque closed-loop control, and the direct-axis current Id is used for excitation control. Then, according to the set position, speed or torque mode, the target voltage Vd and Vq are obtained by the corresponding outer-loop PID regulator. After inverse Park transformation, they are sent to the SVPWM modulation module to calculate the duty cycle of the three-phase bridge arm, thereby generating a six-channel complementary PWM wave with dead time to drive the IPM inverter drive module, which inverts the DC bus voltage into a three-phase sinusoidal voltage with adjustable frequency and amplitude to drive the servo motor.

[0010] A further technical solution of the present invention includes a motor temperature detection circuit connected to the MCU. The motor temperature detection circuit is used to collect the servo motor temperature signal. The MCU is also used to monitor the three-phase current, bus voltage, encoder calibration and motor temperature signal in real time. When a fault trigger condition occurs, the PWM is immediately blocked and a fault code is reported through the UART communication interface.

[0011] A further technical solution of the present invention is that the fault triggering conditions include phase loss, overcurrent, overvoltage, overspeed, overtemperature, or encoder malfunction.

[0012] A further technical solution of the present invention includes a discharge resistor circuit connected to the main control MCU. The discharge resistor circuit is controlled by the main control MCU and is used to discharge the residual high voltage of the DC bus when the power is off or the machine is shut down.

[0013] A further technical solution of the present invention includes a fan drive circuit connected to the main control MCU, the fan drive circuit being used to drive a cooling fan to dissipate heat during power operation.

[0014] A further technical solution of the present invention is that the fan drive circuit includes an AC fan drive sub-circuit and a DC fan drive sub-circuit; the main control MCU controls the start / stop or speed adjustment of the AC fan and DC fan respectively according to the temperature of the power device or the motor temperature.

[0015] 8. The servo drive control system for the motor tensioner according to claim 1, wherein the main control MCU is an ARM Cortex-M4.

[0016] A further technical solution of the present invention is that the UART communication interface interacts with the display panel to realize parameter setting and data feedback.

[0017] To achieve the above objectives, the present invention also proposes a servo drive control method for a motor tensioner, applied to the servo drive control system for a motor tensioner as described above, comprising the following steps: S1. When the system is powered on, the AC input rectifier and filter circuit outputs the DC bus voltage, the switching power supply circuit outputs multiple low-voltage power supplies, the main control MCU completes peripheral initialization, and the system enters standby mode, waiting for the host computer or display panel to send control commands and parameters. S2. The main control MCU receives control commands and selects the position control mode, speed control mode, or torque control mode; it obtains the rotor angle and speed feedback of the two servo motors through the dual-channel SPI absolute encoder interface; it collects the two-phase current of the motor through the dual-channel three-phase current detection circuit, calculates the third-phase current, and performs Clarke transformation and Park transformation on the three-phase current to obtain the quadrature axis current Iq and direct axis current Id in the rotating coordinate system. S3. Execute the corresponding outer loop PID calculation according to the selected control mode to obtain the target voltages Vd and Vq of the d / q axes; after inverse Park transformation of Vd and Vq, input them into the SVPWM module to generate six complementary PWM waves with dead time, drive the dual-channel IPM inverter drive module to invert the DC bus voltage into a three-phase sinusoidal voltage, and drive the two servo motors to run independently respectively. S4. During operation, the main control MCU collects three-phase current, bus voltage, and motor winding temperature in real time, and verifies the validity of the encoder signal. When a phase loss, overcurrent, overvoltage, undervoltage, overspeed, overtemperature, or encoder malfunction is detected, all PWM outputs are immediately blocked, and the corresponding fault code is reported to the outside via the UART communication interface. S5. When a system shutdown, power failure, or bus voltage exceeding the discharge threshold is detected, the main control MCU controls the discharge resistor circuit to conduct, releasing the residual high voltage of the DC bus; at the same time, based on the collected temperature signal, the fan drive circuit is controlled to drive the cooling fan for heat dissipation; the UART communication interface transmits motor operating status data back to the display panel in real time.

[0018] The beneficial effects of the servo drive control system and method for the motor tensioner of the present invention are: This invention solves the technical problems of poor torque control accuracy, lack of protection mechanism, and insufficient independent control capability of dual motors in existing tension controllers; it realizes independent position, speed, and torque vector control of two servo motors, and at the same time builds a multi-software and hardware collaborative protection mechanism, which improves the operational safety, control accuracy and response speed of the intelligent tension controller. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the circuit structure of the main control MCU; Figure 2 and Figure 3 This is a schematic diagram of the AC input rectifier and filter circuit. Figure 4 This is a schematic diagram of the circuit structure of a switching power supply circuit (step-down circuit); Figure 5 and Figure 6 This is a schematic diagram of the circuit structure of a dual-channel IPM inverter drive module; Figure 7 and Figure 8 This is a schematic diagram of the circuit structure of two servo motors; Figure 9 This is a schematic diagram of the circuit structure of the UART communication interface; Figure 10 This is a schematic diagram of the circuit structure of the bleeder resistor circuit; Figure 11 and Figure 12 This is a schematic diagram of the circuit structure of the motor temperature detection circuit; Figure 13 and Figure 14 This is a schematic diagram of the fan drive circuit. Figure 15 and Figure 16 This is a schematic diagram of the operational amplifier circuit. Figure 17and Figure 18 This is a schematic diagram of an auto-lock circuit. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0021] This invention proposes a servo drive control system for a motor tensioner, such as... Figures 1 to 18 As shown, a preferred embodiment of the motor tensioner servo drive control system of the present invention includes an ARM Cortex-M4 main control MCU, an AC input rectifier and filter circuit connected to the ARM Cortex-M4 main control MCU, a switching power supply circuit, a dual-channel IPM inverter drive module, a dual-channel three-phase current detection circuit, and a dual-channel SPI absolute encoder interface.

[0022] The AC input rectifier and filter circuit is used to convert AC mains power into DC bus voltage; the switching power supply circuit is electrically connected to the AC input rectifier and filter circuit, and outputs multiple low-voltage power supplies to power various components of the system.

[0023] The dual-channel IPM inverter drive module drives two servo motors respectively; the dual-channel three-phase current detection circuit collects the two-phase current signals of the corresponding servo motors and sends them to the main control MCU; the dual-channel SPI absolute encoder interface obtains the rotor angle and speed feedback signals of the two servo motors.

[0024] The main control MCU is equipped with a field-oriented FOC algorithm module and an SVPWM modulation module. It is used to generate six PWM signals to drive the IPM inverter to a three-phase sinusoidal voltage to drive the servo motor according to the position control mode, speed control mode, or torque control mode. Based on the feedback of the dual-channel three-phase current detection circuit and the dual-channel SPI absolute encoder interface, vector closed-loop and SVPWM modulation are performed to realize independent position closed-loop control, speed closed-loop control, and torque closed-loop control of the two servo motors.

[0025] In this embodiment, the dual-channel SPI absolute encoder interface is also used to acquire the rotor angle and speed of each servo motor in real time. The three-phase current detection circuit is also used to collect the two-phase current of each servo motor and calculate the third-phase current. The MCU is also used to convert the third-phase current through Clarke transformation and Park transformation to obtain the quadrature-axis current Iq and direct-axis current Id in the rotating coordinate system. The quadrature-axis current Iq is used for servo torque closed-loop control, and the direct-axis current Id is used for excitation control. Then, according to the set position, speed or torque mode, the target voltage Vd and Vq are obtained by the corresponding outer-loop PID regulator. After inverse Park transformation, they are sent to the SVPWM modulation module to calculate the duty cycle of the three-phase bridge arm, thereby generating a six-channel complementary PWM wave with dead time to drive the IPM inverter drive module, which inverts the DC bus voltage into a three-phase sinusoidal voltage with adjustable frequency and amplitude to drive the servo motor.

[0026] In this embodiment, as Figure 11 and Figure 12 As shown, the motor tensioner servo drive control system also includes a motor temperature detection circuit connected to the MCU. This circuit collects the servo motor temperature signal. The MCU also monitors the three-phase current, bus voltage, encoder calibration, and motor temperature signal in real time. When a fault trigger condition occurs, it immediately blocks the PWM and reports a fault code via the UART communication interface. The UART communication interface interacts with the display panel to achieve parameter setting and data feedback.

[0027] The fault triggering conditions include phase loss, overcurrent, overvoltage, overspeed, overtemperature, or encoder malfunction.

[0028] like Figure 10 As shown in this embodiment, the motor tensioner servo drive control system further includes a discharge resistor circuit connected to the main control MCU. The discharge resistor circuit is controlled by the main control MCU and is used to discharge the residual high voltage of the DC bus when the power is off or the machine is shut down.

[0029] In this embodiment, the motor tensioner servo drive control system further includes a fan drive circuit connected to the main control MCU, which is used to drive a cooling fan to dissipate heat during power operation.

[0030] like Figure 13 and Figure 14 As shown, in this embodiment, the fan drive circuit includes an AC fan drive sub-circuit and a DC fan drive sub-circuit; the main control MCU controls the AC fan and DC fan to start / stop or adjust their speed according to the temperature of the power device or the motor.

[0031] Furthermore, in this embodiment, the motor tensioner servo drive control system also includes, for example, Figure 15 and Figure 16 The operational amplifier circuit shown is as follows: Figure 17 and Figure 18 The auto-lock circuit shown.

[0032] In this embodiment, the IPM inverter drive module can be replaced with six discrete IGBTs or MOSFET power transistors, and paired with the three-phase bridge drive chip IR2136 to achieve the same three-phase inverter drive function.

[0033] The structure and working principle of the servo drive control system for the motor tensioner of the present invention will be further described in detail below.

[0034] The servo drive control system for the motor tensioner of this invention mainly consists of an AC input rectifier and filter circuit, a switching power supply circuit, an ARM Cortex-M4 main control MCU, a dual-channel IPM inverter drive module, a dual-channel three-phase current detection circuit, a dual-channel SPI absolute encoder interface (controller motherboard M1 and M2 ports), a motor temperature detection circuit, a bleeder resistor circuit, an AC / DC fan drive circuit, and a UART communication interface (controller motherboard Display port).

[0035] After power-on, the switching power supply generates low-voltage power supply, the main control MCU completes initialization and establishes DC bus voltage, and waits for instructions from the host computer; after receiving the mode and parameter settings, according to the position control (closed-loop positioning accuracy up to 0.05°), speed control (speed response bandwidth 2000Hz), or torque control (torque accuracy ±2% of rated torque) mode, it uses encoder angle and three-phase current feedback to perform vector closed-loop and SVPWM modulation, generating six PWM drive IPMs to invert into three-phase sinusoidal voltage, realizing independent speed, position, or resistance adjustment of the two motors.

[0036] It should be noted that this invention is based on field-oriented control (FOC) and SVPWM modulation technology. First, the rotor angle and speed are acquired in real time through an SPI absolute encoder. At the same time, a three-phase current detection circuit is used to collect the two-phase current of the motor and calculate the third-phase current. The main control MCU converts the three-phase current into quadrature-axis current (Iq, relative to stress torque) and direct-axis current (Id, corresponding to excitation) in the rotating coordinate system through Clarke and Park transformations. Then, according to the set position, speed or torque mode, the corresponding outer-loop PID regulator obtains the target voltage command (Vq, Vd). After inverse Park transformation, it is sent to the SVPWM module to calculate the duty cycle of the three-phase bridge arm, thereby generating a six-channel complementary PWM wave with dead time to drive the IPM module, which inverts the DC bus voltage into a three-phase sinusoidal voltage with adjustable frequency and amplitude to drive the servo motor.

[0037] This invention relates to a servo drive control system for a motor-driven resistance band. During operation, it monitors three-phase current, bus voltage, encoder calibration, and NTC temperature signals in real time. In the event of phase loss, overcurrent, overvoltage, overspeed, overtemperature, or encoder malfunction, the MCU immediately blocks the PWM and reports fault codes (E-02~E-08) via UART. During power failure or shutdown, the high-voltage bus voltage is quickly released through a bleeder resistor, and a fan assists in cooling. Simultaneously, the UART interface interacts with the display panel to achieve parameter setting and data feedback. This invention integrates multiple hardware and software protections, and its AC-DC isolation design complies with safety regulations. It is compatible with 50-120kg servo motors with a rated power of 2.2kW and is suitable for high-precision dual-motor drive control in intelligent resistance bands and strength training equipment.

[0038] This invention achieves independent and precise control of the position, speed, and torque of two servo motors through the coordinated operation of dual independent IPM inverter modules, dual SPI absolute encoders, and dual three-phase current detection circuits. The position control accuracy reaches 0.05 degrees, the torque control accuracy reaches ±2% of the rated torque, and the speed response bandwidth reaches 2000Hz. This meets the precise simulation requirements of dynamic loads in different training modes (such as constant speed, centrifugal, centripetal, and elastic band simulation) for tension equipment. Simultaneously, the controller integrates multiple hardware and software protection mechanisms, including bus overvoltage, undervoltage, three-phase loss, overcurrent, short circuit, overtemperature, overspeed, and encoder calibration anomaly protection. When any anomaly occurs, the MCU can immediately block the P... The WM output reports specific fault codes (E-02~E-08) via UART, effectively preventing damage to the IPM module and motor, and significantly improving the system's safety and reliability. The bleeder resistor circuit quickly releases residual high voltage on the bus when power is off or the system is shut down, ensuring the safety of maintenance personnel. The independent drives of the AC and DC fans, combined with the heat sink structure, ensure that the power devices operate continuously and stably under rated conditions, extending the controller's lifespan. The UART communication interface (Display interface) supports bidirectional data interaction with the host computer or display screen, facilitating users to set parameters and monitor operating status in real time, improving the human-machine interaction experience. The AC-DC isolation design meets safety regulations, enhancing electrical safety.

[0039] In summary, this invention provides a high-precision, high-response, and high-reliability dual-motor servo drive control solution for intelligent resistance bands and strength training equipment.

[0040] To achieve the above objectives, the present invention also proposes a servo drive control method for a motor tensioner, applied to the servo drive control system for a motor tensioner as described above, comprising the following steps: S1. When the system is powered on, the AC input rectifier and filter circuit outputs the DC bus voltage, the switching power supply circuit outputs multiple low-voltage power supplies, the main control MCU completes peripheral initialization, and the system enters standby mode, waiting for control commands and parameters to be sent by the host computer or display panel.

[0041] S2. The main control MCU receives control commands and selects the position control mode, speed control mode, or torque control mode; it obtains the rotor angle and speed feedback of the two servo motors through the dual-channel SPI absolute encoder interface; it collects the two-phase current of the motor through the dual-channel three-phase current detection circuit, calculates the third-phase current, and performs Clarke transformation and Park transformation on the three-phase current to obtain the quadrature axis current Iq and direct axis current Id in the rotating coordinate system.

[0042] S3. Execute the corresponding outer loop PID calculation according to the selected control mode to obtain the target voltages Vd and Vq of the d / q axes; after inverse Park transformation of Vd and Vq, input them into the SVPWM module to generate six complementary PWM waves with dead time, drive the dual-channel IPM inverter drive module to invert the DC bus voltage into a three-phase sine wave voltage, and drive the two servo motors to run independently.

[0043] S4. During operation, the main control MCU collects three-phase current, bus voltage, and motor winding temperature in real time, and verifies the validity of the encoder signal. When a phase loss, overcurrent, overvoltage, undervoltage, overspeed, overtemperature, or encoder malfunction is detected, all PWM outputs are immediately blocked, and the corresponding fault code is reported to the outside via the UART communication interface.

[0044] S5. When a system shutdown, power failure, or bus voltage exceeding the discharge threshold is detected, the main control MCU controls the discharge resistor circuit to conduct, releasing the residual high voltage of the DC bus; at the same time, based on the collected temperature signal, the fan drive circuit is controlled to drive the cooling fan for heat dissipation; the UART communication interface transmits motor operating status data back to the display panel in real time.

[0045] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A servo drive control system for a motor tensioner, characterized in that, include: The main control MCU, and connected to the main control MCU are an AC input rectifier and filter circuit, a switching power supply circuit, a dual-channel IPM inverter drive module, a dual-channel three-phase current detection circuit, and a dual-channel SPI absolute encoder interface; The AC input rectifier and filter circuit is used to convert AC mains power into DC bus voltage; the switching power supply circuit is electrically connected to the AC input rectifier and filter circuit and outputs multiple low-voltage power supplies to power various components in the system. The dual-channel IPM inverter drive module drives two servo motors respectively; the dual-channel three-phase current detection circuit collects the two-phase current signals of the corresponding servo motors and sends them to the main control MCU; the dual-channel SPI absolute encoder interface obtains the rotor angle and speed feedback signals of the two servo motors. The main control MCU is equipped with a field-oriented FOC algorithm module and an SVPWM modulation module. It is used to generate six PWM signals to drive the IPM inverter to a three-phase sinusoidal voltage to drive the servo motor according to the position control mode, speed control mode, or torque control mode. Based on the feedback of the dual-channel three-phase current detection circuit and the dual-channel SPI absolute encoder interface, vector closed-loop and SVPWM modulation are performed to realize independent position closed-loop control, speed closed-loop control, and torque closed-loop control of the two servo motors.

2. The servo drive control system for the motor tensioner according to claim 1, characterized in that, The dual-channel SPI absolute encoder interface is also used to acquire the rotor angle and speed of each servo motor in real time. The three-phase current detection circuit is also used to collect the two-phase current of each servo motor and calculate the third-phase current. The MCU is also used to convert the third-phase current through Clarke transformation and Park transformation to obtain the quadrature-axis current Iq and direct-axis current Id in the rotating coordinate system. The quadrature-axis current Iq is used for servo torque closed-loop control, and the direct-axis current Id is used for excitation control. Then, according to the set position, speed or torque mode, the target voltage Vd and Vq are obtained by the corresponding outer-loop PID regulator. After inverse Park transformation, they are sent to the SVPWM modulation module to calculate the duty cycle of the three-phase bridge arm, thereby generating a six-channel complementary PWM wave with dead time to drive the IPM inverter drive module, which inverts the DC bus voltage into a three-phase sinusoidal voltage with adjustable frequency and amplitude to drive the servo motor.

3. The servo drive control system for the motor tensioner according to claim 2, characterized in that, It also includes a motor temperature detection circuit connected to the MCU. The motor temperature detection circuit is used to collect the servo motor temperature signal. The MCU is also used to monitor the three-phase current, bus voltage, encoder calibration and motor temperature signal in real time. When a fault trigger condition occurs, the PWM is immediately blocked and a fault code is reported through the UART communication interface.

4. The servo drive control system for the motor tensioner according to claim 3, characterized in that, The fault triggering conditions include phase loss, overcurrent, overvoltage, overspeed, overtemperature, or encoder malfunction.

5. The servo drive control system for the motor tensioner according to claim 3, characterized in that, It also includes a bleed resistor circuit connected to the main control MCU. The bleed resistor circuit is controlled by the main control MCU and is used to bleed the residual high voltage of the DC bus when the power is off or the machine is shut down.

6. The servo drive control system for the motor tensioner according to claim 3, characterized in that, It also includes a fan drive circuit connected to the main control MCU, which is used to drive a cooling fan to dissipate heat during power operation.

7. The servo drive control system for the motor tensioner according to claim 6, characterized in that, The fan drive circuit includes an AC fan drive sub-circuit and a DC fan drive sub-circuit; the main control MCU controls the start / stop or speed adjustment of the AC fan and DC fan according to the temperature of the power device or the motor.

8. The servo drive control system for the motor tensioner according to claim 1, characterized in that, The main control MCU is an ARM Cortex-M4.

9. The servo drive control system for the motor tensioner according to claim 3, characterized in that, The UART communication interface interacts with the display panel to enable parameter setting and data feedback.

10. A servo drive control method for a motor tensioner, characterized in that, The servo drive control system for the motor tensioner according to any one of claims 1 to 10 includes the following steps: S1. When the system is powered on, the AC input rectifier and filter circuit outputs the DC bus voltage, the switching power supply circuit outputs multiple low-voltage power supplies, the main control MCU completes peripheral initialization, and the system enters standby mode, waiting for the host computer or display panel to send control commands and parameters. S2. The main control MCU receives control commands and selects the position control mode, speed control mode, or torque control mode; it obtains the rotor angle and speed feedback of the two servo motors through the dual-channel SPI absolute encoder interface; it collects the two-phase current of the motor through the dual-channel three-phase current detection circuit, calculates the third-phase current, and performs Clarke transformation and Park transformation on the three-phase current to obtain the quadrature axis current Iq and direct axis current Id in the rotating coordinate system. S3. Execute the corresponding outer loop PID calculation according to the selected control mode to obtain the target voltages Vd and Vq of the d / q axes; after inverse Park transformation of Vd and Vq, input them into the SVPWM module to generate six complementary PWM waves with dead time, drive the dual-channel IPM inverter drive module to invert the DC bus voltage into a three-phase sinusoidal voltage, and drive the two servo motors to run independently respectively. S4. During operation, the main control MCU collects three-phase current, bus voltage, and motor winding temperature in real time, and verifies the validity of the encoder signal. When a phase loss, overcurrent, overvoltage, undervoltage, overspeed, overtemperature, or encoder malfunction is detected, all PWM outputs are immediately blocked, and the corresponding fault code is reported to the outside via the UART communication interface. S5. When a system shutdown, power failure, or bus voltage exceeding the discharge threshold is detected, the main control MCU controls the discharge resistor circuit to conduct, releasing the residual high voltage of the DC bus; at the same time, based on the collected temperature signal, the fan drive circuit is controlled to drive the cooling fan for heat dissipation; the UART communication interface transmits motor operating status data back to the display panel in real time.

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