Operation and control integrated servo motor driver

Abstract

The invention discloses an operation and control integrated servo motor driver, which comprises a control module and a driving module, the control module and the driving module can realize high-speed real-time interaction of motor state parameters and control parameters through a reflective memory mechanism, the control module is a high-performance ARM controller, the high-performance ARM controller comprises a CPU0 and a CPU1, and the CPU0 and the CPU1 are connected with each other. The driving module is composed of a plurality of FPGA driving control units. According to the invention, the control module and the driving module are creatively integrated, and the control module adopts a high-performance ARM controller, so that a complex control algorithm can be efficiently processed; and the driving module is composed of a plurality of FPGA driving control units, so that the accuracy and reliability of motor driving are ensured. Meanwhile, according to the design, the size of the servo motor driving control system is effectively reduced, the integration level and the intelligent level of the system are remarkably improved, rapid development of the control system in the miniaturization and intelligent direction is promoted, and the market competitiveness of products is further enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of servo motor drives, and particularly relates to a servo motor driver integrating motion control. Background Art

[0002] With the continuous development of industrial automation and intelligent manufacturing technologies, servo motor drivers are increasingly widely used in various automation equipment and robots. As the core component for controlling servo motors, the performance of servo motor drivers directly affects the accuracy, stability, and response speed of the entire system. Especially in high-end manufacturing fields such as semiconductor processing, precision instrument manufacturing, and industrial robots, the performance requirements for servo motor drivers are getting higher and higher. It is not only necessary to achieve precise position control and speed control, but also to have fast response, high reliability, and good anti-interference capabilities.

[0003] Most of the existing servo motor drivers adopt a split design, that is, the control module and the drive module are arranged separately. Although this design meets the control requirements of servo motors to a certain extent, there are the following problems: First, the system volume is large. Since the control module and the drive module are separated, more connecting wires and interfaces are required, resulting in a larger volume of the entire driver, which is not conducive to the integration of equipment with compact space. This problem is particularly prominent in fields with strict space requirements such as industrial robots and medical devices. Second, the response speed is limited. The split design causes a certain delay in the signal transmission process, affecting the real-time performance and response speed of the system. Especially in high-speed and high-precision motion control scenarios, such as high-speed cutting of numerically controlled machine tools and rapid grasping of industrial robots, this delay may lead to a decrease in control accuracy or even system instability. Third, the system complexity is high. The split design increases the system complexity, not only increasing the probability of faults but also increasing the maintenance cost. According to statistics, about 35% of the faults in servo systems with split design originate from the connection problems between the control module and the drive module. Finally, the integration level is low. The integration level of the control module and the drive module of the existing drivers is not high, which is not conducive to the development trend of miniaturization and intelligence. With the advancement of Industry 4.0 and intelligent manufacturing, the intelligent requirements for servo systems are getting higher and higher, and the existing split design is difficult to meet these new needs.

[0004] In view of the above problems, it is necessary to study a new type of servo motor driver to achieve a high degree of integration of the control module and the drive module, improve the response speed, stability, and integration level of the system, and meet the requirements of modern automation equipment for high-performance and compact servo motor drivers. Summary of the Invention

[0005] The object of the present invention is to provide a servo motor driver integrating motion control. In view of the market demand for high integration, response speed and stability of servo motor drivers, a technical solution for integrating motion control of servo motor drivers is provided.

[0006] To achieve the above object, the present invention provides the following technical solution: A servo motor driver integrating motion control includes a control module and a drive module. The control module and the drive module can achieve high-speed real-time interaction of motor state parameters and control parameters through the reflective memory mechanism. Among them, the control module is a high-performance ARM controller, which includes CPU0 and CPU1, and the drive module is composed of multiple FPGA drive control units. The FPGA drive control unit includes a motor control module, a signal processing module, an IO expansion module and an algorithm acceleration module, which are used to achieve high-performance control of the servo motor.

[0007] Preferably, the reflective memory mechanism is a high-speed communication technology based on shared memory. There is a data connection between the control module and the drive module, and the data transmission rate can reach the Gbps level.

[0008] Preferably, CPU0 includes an interface expansion module, a status monitoring module, a parameter management module and a coordinate transformation module, which are used to achieve system management functions.

[0009] Preferably, CPU1 includes a motion control module and a motor drive module. The motion control module adopts an advanced trajectory generation algorithm and supports multiple motion modes such as S-shaped curves and polynomial interpolation. The motor drive module generates PWM signals through a real-time control algorithm.

[0010] Preferably, the reflective memory mechanism is implemented based on a shared dual-port RAM. The ARM controller and the FPGA respectively access the same physical memory area through independent address buses.

[0011] Preferably, the FPGA drive control unit includes modules such as motor control, signal processing, IO expansion, and algorithm acceleration. The motor control module is responsible for the closed-loop control of the current loop, speed loop and position loop, and adopts space vector modulation (SVPWM) technology to improve the motor drive efficiency.

[0012] Preferably, the drive module is an integrated motor module based on FPGA technology. The FPGA chip collects three-phase current feedback information through a Σ-Δ ADC, analyzes the position data of the encoder, and transmits control information to the ARM controller through the reflective memory mechanism.

[0013] Preferably, the control module is used to transmit the signals of the grating scale position sensor, the strain gauge torque sensor, and the Hall current sensor in real time through the reflection memory mechanism to the ARM controller, and then output control instructions to the power drive circuit through modules such as algorithm acceleration and IO expansion, so as to achieve high-precision control of the servo motor.

[0014] Preferably, the drive control method includes designing feedforward compensation and resonance suppression algorithms, which are applied to the controller to generate control signals, so as to realize a real-time control loop of command-execution-feedback.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] 1. The present invention is not aimed at a specific model of servo motor. The design scheme is applicable to the control systems of various servo motors, with wide applicability. At the same time, the servo motor driver of the present invention integrates a drive module and a control module, and can achieve high response speed and high stability of the servo motor control system. Through the reflection memory mechanism and FPGA acceleration technology, microsecond-level data transmission and computing capabilities are achieved, significantly improving the response speed and control accuracy of the system.

[0017] 2. The present invention can effectively reduce the volume of the drive control system, which is beneficial to the development of the control system towards miniaturization and intelligence. By optimizing the hardware design and control algorithms, the system complexity is reduced, the probability of faults is decreased, and the stability and reliability of the system are improved. At the same time, it supports multiple communication protocols and advanced control algorithms, facilitating the realization of the intelligence and networking of the servo motor control system, and meeting the development needs of Industry 4.0 and intelligent manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the integrated motion and control module of the present invention;

[0019] Figure 2 It is a detailed structural schematic diagram of the control module and the drive module of the present invention;

[0020] Figure 3 It is a schematic diagram of the integrated motion and control system of the six-joint industrial robot of the present invention;

[0021] Figure 4 It is a physical diagram of the nano-level integrated motion and control servo motor driver of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0023] Please refer to Figures 1-4 , the present invention provides a technical solution: a servo motor driver integrating motion control, including a control module and a drive module. The control module and the drive module can achieve high-speed real-time interaction of motor state parameters and control parameters through the reflective memory mechanism. Among them, the control module is a high-performance ARM controller, the high-performance ARM controller includes CPU0 and CPU1, and the drive module is composed of multiple FPGA drive control units, and the FPGA drive control unit includes a motor control module, a signal processing module, an IO expansion module and an algorithm acceleration module for realizing high-performance control of the servo motor.

[0024] The ARM controller of the present invention, that is, a microprocessor based on the ARM architecture, is a high-performance and low-power embedded processing solution.

[0025] In the specific implementation manner of the present invention, the adopted ARM controller is responsible for realizing the core operation and control functions of the servo motor driver. This controller has a rich instruction set and high processing ability, can quickly process motor state data, execute complex algorithms including PID control, fuzzy control and adaptive control, and ensure the stable operation of the system. By integrating multiple communication interfaces such as CAN, EtherCAT, SPI and RS485, the ARM controller can achieve data interaction with the upper computer, external sensors and human-machine interaction devices. For example, multi-axis synchronous control is realized based on the EtherCAT protocol, or real-time instructions of the distributed system are received through the CAN bus. In addition, the ARM controller adopts a multi-core architecture, such as a dual-core Cortex-A series, where CPU0 is responsible for interface expansion, status monitoring, parameter management and coordinate transformation, specifically including motor temperature monitoring, current fluctuation analysis, dynamic parameter adjustment and Clark, Park coordinate transformation; CPU1 focuses on motion control and motor drive, executes trajectory planning, interpolation calculation and generates closed-loop instructions for the current loop and speed loop. The ARM controller is equipped with a real-time operating system to ensure the determinacy of task scheduling, meet the microsecond-level real-time requirements, and at the same time the ARM controller can achieve efficient interaction with external devices, providing strong support for the miniaturization and intelligentization of the servo motor driver.

[0026] The FPGA (Field Programmable Gate Array) of the present invention is an integrated circuit that can be programmed through a hardware description language.

[0027] In the present invention, the FPGA adopts a parallel processing architecture, and its internal logic modules include a motor control module, a signal processing module, an IO expansion module, and an algorithm acceleration module. The motor control module is used to generate PWM signals and implement dead-time compensation; the signal processing module is responsible for filtering current and voltage signals and quadrature decoding encoder signals; the IO expansion module supports multi-channel differential signal input and output; the algorithm acceleration module implements the SVPWM algorithm and position-loop PID calculation through hardware logic. The FPGA can update its logic function through the JTAG interface to meet the requirements of different models of servo motors. Its parallel processing ability enables it to synchronously complete current sampling, encoder position parsing, and PWM signal output within a 1-microsecond time window, significantly reducing the control loop delay and ensuring the high-speed response of the servo motor.

[0028] In an embodiment of the present invention, as Figure 1 shown, it is a schematic diagram of the module structure of the integrated motion control in the embodiment of the present invention. The driver includes a control module and a drive module, and the control module and the drive module achieve high-speed real-time interaction of motor state parameters and control parameters through the reflective memory mechanism. The reflective memory mechanism is based on a shared dual-port RAM, and the ARM controller and the FPGA respectively access the same physical memory area through independent address buses. The ARM controller writes real-time control instructions such as target position, speed, and torque to the specified address of the reflective memory mechanism, and the FPGA reads the data at a fixed period of 100 nanoseconds and converts it into a PWM control signal; at the same time, the FPGA writes motor state data such as three-phase current, encoder position, and temperature information to another address of the reflective memory mechanism, and the ARM controller reads and updates the control algorithm parameters through an interrupt trigger method. This mechanism avoids the protocol parsing overhead of traditional bus communication, realizes sub-microsecond data transmission, and ensures the real-time performance of the control system.

[0029] The control module is a high-performance ARM control, and the drive module consists of multiple FPGA drive control units. The high-performance ARM controller includes CPU0 and CPU1. CPU0 contains an interface expansion module, a status monitoring module, a parameter management module, and a coordinate transformation module. Among them, the interface expansion module supports the parsing of EtherCAT master protocol stack and Modbus-TCP protocol. The status monitoring module diagnoses motor overcurrent, overvoltage, and overheating faults in real time. The parameter management module dynamically adjusts PID parameters through the GUI interface. The coordinate transformation module converts the three-phase current of the motor into d-q axis components. CPU1 contains a motion control module and a motor drive module. The motion control module realizes S-shaped acceleration and deceleration planning and multi-axis interpolation operation. The motor drive module generates closed-loop control instructions for the speed loop and the position loop. The FPGA drive control unit includes a motor control module, a signal processing module, an IO expansion module, and an algorithm acceleration module. Among them, the motor control module realizes space vector modulation and dead-time compensation. The signal processing module performs debounce filtering on Hall signals and quadruple frequency decoding on encoder signals. The IO expansion module provides 16 digital inputs and 12 analog outputs. The algorithm acceleration module realizes Kalman filtering and FFT analysis through hardware logic.

[0030] The drive module of the servo motor driver is an integrated motor module based on FPGA technology. In this module, the FPGA chip collects three-phase current feedback information at a sampling rate of 1MHz through a Σ-Δ ADC, and parses the position data of the incremental encoder or the absolute encoder, and transmits control information to the ARM controller through the reflective memory mechanism. At the same time, the FPGA uses the digital-analog IO interface to output PWM waves, enable signals, and fault reset signals to the power drive circuit. The power drive circuit is designed based on IGBT modules, supports a bus voltage of 600V and a peak current of 50A, and integrates overcurrent, overvoltage, and overheating protection functions. The FPGA monitors the IGBT temperature and the bus voltage in real time, immediately shuts down the PWM output when an abnormality is detected, and sends a fault code to the ARM controller through the reflective memory mechanism. The control module of the servo motor driver is used to transmit the signals collected by the position sensor and the torque sensor, as well as information such as the current of the servo motor, to the ARM controller in real time through the reflective memory mechanism, and outputs control instructions to the power drive circuit through modules such as algorithm acceleration and IO expansion to achieve high-precision control of the servo motor.

[0031] The control module of the servo motor driver is used to transmit the signals of the grating scale position sensor, the strain gauge torque sensor and the Hall current sensor to the ARM controller in real time through the reflection memory mechanism. The ARM controller processes the data through the floating-point arithmetic coprocessor. For example, the Runge-Kutta method is used to solve the motor dynamics model, or the control parameters are dynamically adjusted through the fuzzy PID algorithm. The finally generated control instructions are transmitted to the power drive circuit through the differential output IO expansion module to achieve high-precision control of the servo motor.

[0032] Working principle: In the application embodiment of the present invention, as Figure 3 shown, it is a schematic diagram of the motion and control integrated system of the six-joint industrial robot in the embodiment of the present invention. This system uses the AXI bus protocol and works in cooperation with the programmable logic module and the drive board through the processing system to complete the precise control of the six-joint industrial robot. The processing system includes motion control, position control and speed control. The processing system integrates the functions of motion control, position control and speed control and runs based on the Linux operating system. The system communicates with external devices or networks through Ethernet and supports the TCP / IP protocol stack. The human-machine interface is developed using graphic libraries such as Qt / GTK to provide user interaction and system monitoring functions. In the programmable logic module, the signal processing module receives the input information from the ADC interface and the encoder interface, works in cooperation with the multi-axis timing control module, and interacts with the current control module. The current control module generates a PWM wave and inputs it into the PWM generator. This module receives the d-axis and q-axis current reference values, adjusts the current using the PI controller, and generates the corresponding control signals. Through the inverse Park transformation and the inverse Clark transformation, the module converts the d-axis and q-axis current signals into current signals in the three-phase stationary coordinate system; at the same time, through the Park transformation and the Clark transformation, the abc three-phase current signals are converted into current signals in the two-phase rotating coordinate system. The drive board includes an analog-to-digital converter and an intelligent power module, which are used to convert digital signals into analog signals and drive the joint motors to operate.

[0033] In summary, the present invention provides a design scheme of a motion and control integrated servo driver for the control requirements of the integration, response speed and stability of the servo motor. In the industrial robot scenario, the present invention can achieve six-axis linkage control through EtherCAT, the FPGA parallel processes the current loop signals of each axis, and the ARM controller generates joint trajectories through the inverse kinematics algorithm; in the numerical control machine tool scenario, the FPGA achieves high-precision spindle orientation control, and the ARM compensates for mechanical errors through the RTCP algorithm. The present invention supports multi-mode configuration of permanent magnet synchronous motors, AC asynchronous motors and linear motors, and can adapt to the requirements of different application scenarios.

[0034] In summary, the technical problem to be solved by the present invention is to provide a design scheme of a servo drive motor driver integrating motion control for the control requirements of the integration, response speed, and stability of the servo motor, and to provide a test platform for the control algorithm of the servo motor. It has a wide range of application scenarios and can achieve high-precision control of the servo motor. The present invention has no requirements for the model of the servo motor, which can be selected according to specific needs, and can better cope with various usage scenarios.

[0035] The above has introduced in detail a servo motor driver integrating motion control provided by the present invention.

[0036] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0037] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A servo motor driver integrating motion control, comprising a control module and a drive module, characterized in that: The control module and the drive module can achieve high-speed real-time interaction of motor state parameters and control parameters through the reflective memory mechanism. The control module is a high-performance ARM controller, which includes CPU0 and CPU1. The drive module is composed of multiple FPGA drive control units, and the FPGA drive control unit includes a motor control module, a signal processing module, an IO expansion module, and an algorithm acceleration module, which are used to achieve high-performance control of the servo motor.

2. The servo motor driver integrating motion control according to claim 1, characterized in that: The reflective memory mechanism is a high-speed communication technology based on shared memory. There is a data connection between the control module and the drive module, and the data transmission rate can reach the Gbps level.

3. The servo motor driver integrating motion control according to claim 2, characterized in that: CPU0 includes an interface expansion module, a status monitoring module, a parameter management module, and a coordinate transformation module, which are used to implement system management functions.

4. The servo motor driver integrating motion control according to claim 3, characterized in that: CPU1 includes a motion control module and a motor drive module. The motion control module adopts an advanced trajectory generation algorithm, supports various motion modes such as S-shaped curves and polynomial interpolation, and the motor drive module generates PWM signals through a real-time control algorithm.

5. The servo motor driver integrating motion control according to claim 4, characterized in that: The reflective memory mechanism is based on a shared dual-port RAM. The ARM controller and the FPGA respectively access the same physical memory area through independent address buses.

6. The servo motor driver integrating motion control according to claim 5, characterized in that: The FPGA drive control unit includes modules such as motor control, signal processing, IO expansion, and algorithm acceleration. The motor control module is responsible for the closed-loop control of the current loop, speed loop, and position loop, and uses space vector modulation (SVPWM) technology to improve the motor drive efficiency.

7. The servo motor driver integrated with motion control according to claim 6, characterized in that: The drive module is an integrated motor module based on FPGA technology. The FPGA chip collects three-phase current feedback information through a Σ-Δ ADC, analyzes the position data of the encoder, and transmits control information to the ARM controller through the reflective memory mechanism.

8. The servo motor driver integrating motion control according to claim 7, characterized in that: The control module is used to process the signals of the grating scale position sensor, strain gauge torque sensor, and Hall current sensor, and transmit them to the ARM controller in real time through the reflective memory mechanism. Then, through modules such as algorithm acceleration and IO expansion, control instructions are output to the power drive circuit to achieve high-precision control of the servo motor.

9. The servo motor driver integrating motion control according to claim 8, characterized in that: The drive control method includes designing feedforward compensation and resonance suppression algorithms, which are applied to the controller to generate control signals to achieve a real-time control loop of command-execution-feedback.

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