A built-in control driving module and control method of a direct current brush motor electric cylinder

Abstract

The application discloses a built-in control driving module and control method of a direct-current brush motor electric cylinder, and belongs to the technical field of motor control. The module comprises a power driving module, a signal processing module and a protection circuit. The power driving module adopts an integrated H-bridge driving circuit, and the power switch element thereof is a MOSFET tube with low conduction resistance, which is used for driving the motor to run to realize the reciprocating operation of the piston rod. The signal processing module comprises a microcontroller, which is used for receiving external control signals and converting the external control signals into PWM signals, simultaneously collecting current and position information in real time, and dynamically adjusting the PWM duty cycle through a closed-loop control algorithm to realize accurate speed and position control. The protection circuit is used for performing overcurrent, overvoltage and overheat protection. The application improves the control precision, dynamic response performance and energy utilization efficiency of the electric cylinder, enhances the system reliability and service life, and has a compact structure and can be built-in installed, and is suitable for the fields of industrial automation and precise positioning.

Description

Technical Field

[0001] This invention relates to the field of motor control technology, specifically to a control drive circuit for a DC brushed motor electric cylinder, and more particularly to an integrated and intelligent built-in control drive module and control method for a DC brushed motor electric cylinder. Background Technology

[0002] DC brushed motor electric cylinders are a common actuator widely used in industrial automation, robotics, and precision positioning systems. Their core function lies in converting rotary motion into linear motion via motor drive, thereby achieving precise position control and force output. With the increasing demands for intelligent, miniaturized, and energy-efficient equipment in modern industry, optimizing the design of motor drive circuits has become a research hotspot in this field.

[0003] Currently, traditional DC brushed motor drive circuits have limitations in control precision, response speed, and energy efficiency, making it difficult to meet the ever-increasing demands for high performance. Specifically, existing drive circuits typically use discrete components to construct H-bridge circuits, resulting in high on-resistance and high switching losses, leading to low overall energy utilization efficiency. Furthermore, traditional drive circuits lack effective closed-loop control mechanisms, usually relying solely on open-loop PWM speed regulation. When the load changes abruptly, the motor speed and output torque are difficult to maintain stability, resulting in insufficient control precision and dynamic response performance. In addition, existing drive circuits are relatively weak in fault protection; most solutions lack comprehensive overcurrent, overvoltage, and overheat protection mechanisms, making the electric cylinder susceptible to damage under abnormal operating conditions, affecting equipment lifespan and increasing maintenance costs.

[0004] In recent years, the development of power electronics technology has provided new possibilities for improving DC brushed motor drive circuits. In particular, the application of new power devices and control strategies has significantly improved the overall performance of motor drive systems. Against this backdrop, developing a high-efficiency, high-precision DC brushed motor electric cylinder control drive circuit has significant practical importance and broad application prospects. Summary of the Invention

[0005] To address the technical problems of insufficient control precision, poor dynamic response performance, low energy utilization efficiency, and lack of a sound fault protection mechanism in existing DC brushed motor electric cylinder drive circuits, this invention provides a built-in control drive module and control method for a DC brushed motor electric cylinder, aiming to improve the control precision, operating efficiency, and system reliability of the electric cylinder by optimizing circuit design and control strategy.

[0006] To achieve the above objectives, the present invention provides a built-in control drive module for a DC brushed motor electric cylinder, including a power drive module, a signal processing module, and a protection circuit. Power drive module The power drive module adopts an integrated H-bridge drive circuit. The power switching element of the integrated H-bridge drive circuit is a MOSFET with low on-resistance. The power drive module is used to drive a DC brushed motor to achieve the reciprocating operation of the piston rod of the electric cylinder.

[0007] Preferably, the on-resistance of the MOSFET is less than 10mΩ to further reduce switching losses and conduction losses, and improve energy utilization.

[0008] Signal processing module The signal processing module includes a microcontroller. The microcontroller receives external control signals (such as speed commands, position commands, etc.) and converts these signals into PWM signals for controlling the power drive module. The microcontroller also acquires real-time current and position information of the electric cylinder and dynamically adjusts the duty cycle of the PWM signal based on this information using a closed-loop control algorithm to achieve speed and position control of the electric cylinder.

[0009] Preferably, the microcontroller uses an STM32 series or ARM Cortex-M series processor to ensure sufficient computing power and processing speed.

[0010] Preferably, the input port of the signal processing module is provided with an RC filter circuit, which is used to filter the input signal. More preferably, the RC filter circuit is provided at each input / output port of the signal processing module.

[0011] Preferably, transient suppression diodes are respectively provided at the power input terminal of the power drive module and the signal interface of the signal processing module. The transient suppression diodes are used to absorb transient overvoltages to enhance anti-interference capability.

[0012] Protection circuit The protection circuit is connected to the power drive module and the signal processing module respectively, and the protection circuit is used to perform at least one of the protection actions of overcurrent protection, overvoltage protection and overheat protection.

[0013] Preferably, the protection circuit includes an overcurrent protection sub-circuit, an overvoltage protection sub-circuit, and an overheat protection sub-circuit. The overcurrent protection sub-circuit detects the current through a current sampling resistor, the overvoltage protection sub-circuit detects the voltage through a voltage sampling voltage divider resistor, and the overheat protection sub-circuit detects the temperature through a temperature sensor (preferably an NTC thermistor). Each of the protection sub-circuits feeds back the detected physical quantity to the microcontroller or hardware comparator, and cuts off the power output or limits the current when the detected value exceeds a preset threshold.

[0014] More preferably, the overcurrent protection sub-circuit, the overvoltage protection sub-circuit, and the overheat protection sub-circuit respectively feed back the detected current signal, voltage signal, and temperature signal to the microcontroller, and the microcontroller determines whether to trigger a protection action based on each of the signals.

[0015] Integrated structure Preferably, the signal processing module, the power drive module, and the protection circuit are integrated on the same PCB board, which is installed inside the housing of the electric cylinder. This compact, modular design reduces the space required for external wiring and auxiliary equipment, making installation and debugging simpler and faster.

[0016] Control methods A control method for a DC brushed motor electric cylinder, applied to the built-in control drive module of the DC brushed motor electric cylinder described in any of the above technical solutions, includes the following steps: The microcontroller receives external control signals and generates PWM signals based on the external control signals. The PWM signals are used to control the switching state of the integrated H-bridge drive circuit in the power drive module to drive the DC brushed motor to run. Real-time acquisition of current feedback signals and piston rod position feedback signals during the operation of the electric cylinder; The microcontroller calculates the required PWM duty cycle based on the deviation between the target values ​​corresponding to the current feedback signal, the position feedback signal, and the external control signal using a closed-loop control algorithm (preferably an intelligent PID control algorithm), and dynamically adjusts the duty cycle of the output PWM signal to precisely control the motor's speed, direction, and output torque. The protection circuit monitors the system's operating status in real time and executes corresponding protection actions when it detects overcurrent, overvoltage, or overheating abnormalities. Beneficial effects

[0017] Compared with the prior art, the present invention has the following advantages: 1) Improved control accuracy and dynamic response performance: This invention uses a high-performance microcontroller combined with a closed-loop control algorithm to collect the current and position information of the electric cylinder in real time and dynamically adjust the duty cycle of the PWM signal, thereby achieving precise control of the motor speed and torque. Compared with the traditional open-loop control scheme, it significantly improves the position control and speed control accuracy of the electric cylinder, while maintaining excellent dynamic response performance under sudden load changes. 2) Improve energy utilization efficiency: The power drive module of this invention uses MOSFETs with low on-resistance to build an integrated H-bridge drive circuit, which effectively reduces switching losses and conduction losses, reduces energy waste, and thus improves the overall system energy utilization efficiency, which meets the requirements of energy-saving development. 3) Enhanced system reliability and adaptability: This invention effectively prevents damage to the circuit and electric cylinder from abnormal operating conditions by incorporating comprehensive overcurrent, overvoltage, and overheat protection circuits, as well as signal filtering and transient suppression designs. At the same time, the closed-loop control mechanism enables the system to respond quickly to external interference and automatically adjust to the optimal working state, significantly enhancing the system's reliability and environmental adaptability. 4) Extend equipment lifespan and reduce maintenance costs: This invention effectively reduces the risk of damage to electric cylinders under abnormal operating conditions through fault diagnosis and protection mechanisms and intelligent dynamic adjustment capabilities, thereby extending the service life of the equipment and reducing the frequency and cost of daily maintenance and repair. 5) Convenient installation and debugging: The present invention adopts a compact modular structure design, integrating the signal processing module, power drive module and protection circuit on the same PCB board. It can be built into the electric cylinder body, reducing the space occupied by external wiring and supporting equipment, making installation and debugging simpler and faster, and has strong market applicability and competitiveness. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the built-in control and drive module of the DC brushed motor electric cylinder of the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Figure 1 The block diagram shown includes: an external control signal input terminal, a signal processing module (including a microcontroller), a PWM signal output terminal, a power drive module (including an integrated H-bridge drive circuit and MOSFETs), an electric cylinder body (including a DC brushed motor and piston rod), a current / position information feedback terminal, and a protection circuit (including overcurrent / overvoltage / overheat protection and transient suppression diodes).

[0021] like Figure 1 As shown, the present invention provides a built-in control drive module for a DC brushed motor electric cylinder, which mainly includes a power drive module, a signal processing module, and a protection circuit.

[0022] Detailed implementation of the signal processing module The core of the signal processing module is a high-performance microcontroller. External control signals (such as target speed commands or target position commands) are input to the signal processing module via the input port. After receiving the external control signals, the microcontroller converts them into PWM signals suitable for the power drive module. Simultaneously, the microcontroller collects current information and piston rod position information in real time during the operation of the electric cylinder through a current detection circuit (such as a sampling resistor connected in series in the motor power supply circuit in conjunction with a differential amplifier) ​​and position sensors (such as Hall sensors or potentiometers). It then dynamically adjusts the duty cycle of the PWM signal through a built-in closed-loop control algorithm to achieve precise speed and position control. In this embodiment, the microcontroller preferably uses an STM32 series or equivalent ARM Cortex-M series processor to ensure sufficient computing power and processing speed.

[0023] In this embodiment, each input and output port of the signal processing module is equipped with an RC filter circuit. This RC filter circuit is used to filter the input and output signals to remove high-frequency noise interference. Simultaneously, a transient voltage suppressor diode (TVS diode) is also provided at the signal interface of the signal processing module to absorb transient overvoltages, further enhancing the anti-interference capability of signal transmission.

[0024] Detailed implementation of the power drive module The power drive module employs an integrated H-bridge drive circuit, with its core power switching element being a low-on-resistance N-channel MOSFET. Preferably, the on-resistance of the MOSFET is less than 10mΩ to minimize switching and conduction losses and improve energy utilization. The PWM signal output by the microcontroller is amplified by a driver chip (such as a dedicated MOSFET driver IC) and controls the on / off state of the corresponding MOSFET in the H-bridge, thereby controlling the forward and reverse rotation and speed of the brushed DC motor, and realizing the cyclic reciprocating operation control of the electric cylinder piston rod.

[0025] A transient suppression diode is also provided at the power input terminal of the power drive module to absorb transient overvoltages on the power line and prevent surge voltages from damaging the power devices.

[0026] Detailed implementation of the protection circuit The protection circuit is connected to the power drive module and the signal processing module respectively, and is used to perform at least one of the protection actions of overcurrent protection, overvoltage protection and overheat protection.

[0027] In this embodiment, the protection circuit specifically includes an overcurrent protection sub-circuit, an overvoltage protection sub-circuit, and an overheat protection sub-circuit. Wherein: The overcurrent protection sub-circuit detects the current signal through a current sampling resistor connected in series in the motor power supply circuit. The current signal is amplified and fed back to the microcontroller's ADC interface or hardware comparator. The overvoltage protection sub-circuit detects the power supply voltage signal through a voltage sampling divider resistor, and this voltage signal is fed back to the microcontroller's ADC interface or hardware comparator. The overheat protection sub-circuit detects the temperature of the power drive module or the electric cylinder body through a temperature sensor. The temperature sensor is preferably an NTC thermistor. Its resistance value changes with temperature and is converted into a voltage signal by a voltage divider circuit, which is then fed back to the ADC interface of the microcontroller or a hardware comparator.

[0028] In this embodiment, the overcurrent protection sub-circuit, overvoltage protection sub-circuit, and overheat protection sub-circuit respectively feed back the detected current signal, voltage signal, and temperature signal to the microcontroller. The microcontroller compares each signal with a preset threshold to determine whether any detected value exceeds the preset threshold. When any detected value exceeds the preset threshold, the microcontroller performs corresponding protection actions by blocking the PWM output or cutting off the power output at the enable terminal of the control driver chip, or by limiting the current through a current limiting circuit, to prevent damage to the circuit and the electric cylinder.

[0029] Specific implementation methods of integrated structure The control and drive module of this invention adopts a PCB board integration method, integrating the signal processing module, power drive module, and protection circuit on the same circuit board, resulting in a compact overall structure. This module can be internally installed inside the housing of a DC brushed motor electric cylinder, connecting to an external control system via a standard interface for plug-and-play functionality. This reduces the space occupied by external wiring and auxiliary equipment, and facilitates installation and debugging.

[0030] Specific implementation methods of the control method After the system is powered on, the microcontroller initializes all peripherals and reads the initial state. During operation, the microcontroller continuously receives external control commands and acquires the current feedback signal and position feedback signal of the electric cylinder in real time.

[0031] The microcontroller generates a PWM signal based on an external control signal. This PWM signal is used to control the switching state of the integrated H-bridge drive circuit in the power drive module to drive the DC brushed motor.

[0032] During operation, the microcontroller collects the current feedback signal and piston rod position feedback signal of the electric cylinder in real time. Based on the deviation between the target value (target speed or target position) corresponding to the current feedback signal, the position feedback signal, and the external control signal, it calculates the required PWM duty cycle through a closed-loop control algorithm. In this embodiment, the closed-loop control algorithm is preferably an intelligent PID control algorithm, which dynamically adjusts the duty cycle of the output PWM signal through a combination of proportional, integral, and derivative operations to precisely control the motor's speed, direction, and output torque.

[0033] At the same time, the protection circuit monitors the system's operating status (including current, voltage, and temperature) in real time. When overcurrent, overvoltage, or overheating abnormalities are detected, it executes corresponding protection actions (such as cutting off power output or limiting current) to ensure the safe and reliable operation of the system.

[0034] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A built-in control and drive module for a DC brushed motor electric cylinder, characterized in that, include: The power drive module adopts an integrated H-bridge drive circuit, and the power switching element of the integrated H-bridge drive circuit is a MOSFET with low on-resistance. The power drive module is used to drive a DC brushed motor to achieve the reciprocating operation of the piston rod of an electric cylinder. The signal processing module includes a microcontroller. The microcontroller receives external control signals and converts them into PWM signals for controlling the power drive module. The microcontroller also collects the current and position information of the electric cylinder in real time and dynamically adjusts the duty cycle of the PWM signal according to the current and position information through a closed-loop control algorithm to achieve speed and position control of the electric cylinder. A protection circuit is provided, which is connected to the power drive module and the signal processing module respectively. The protection circuit is used to perform at least one of the following protection actions: overcurrent protection, overvoltage protection, and overheat protection.

2. The built-in control and drive module for a DC brushed motor electric cylinder according to claim 1, characterized in that, The protection circuit includes an overcurrent protection sub-circuit, an overvoltage protection sub-circuit, and an overheat protection sub-circuit. The overcurrent protection sub-circuit detects the current through a current sampling resistor, the overvoltage protection sub-circuit detects the voltage through a voltage sampling voltage divider resistor, and the overheat protection sub-circuit detects the temperature through a temperature sensor. Each of the protection sub-circuits feeds back the detected physical quantity to the microcontroller or hardware comparator. When the detected value exceeds a preset threshold, the power output is cut off or the current is limited.

3. The built-in control and drive module for a DC brushed motor electric cylinder according to claim 2, characterized in that, The overcurrent protection sub-circuit, the overvoltage protection sub-circuit, and the overheat protection sub-circuit respectively feed back the detected current signal, voltage signal, and temperature signal to the microcontroller, and the microcontroller determines whether to trigger a protection action based on each of the signals.

4. The built-in control and drive module for a DC brushed motor electric cylinder according to claim 1, characterized in that, The input port of the signal processing module is equipped with an RC filter circuit, which is used to filter the input signal.

5. The built-in control and drive module for a DC brushed motor electric cylinder according to claim 4, characterized in that, The RC filter circuit is located at each input / output port of the signal processing module.

6. The built-in control and drive module for a DC brushed motor electric cylinder according to claim 1, characterized in that, Transient suppression diodes are respectively provided at the power input terminal of the power drive module and the signal interface of the signal processing module. The transient suppression diodes are used to absorb transient overvoltages to enhance anti-interference capability.

7. The built-in control and drive module for a DC brushed motor electric cylinder according to claim 1, characterized in that, The signal processing module, the power drive module, and the protection circuit are integrated on the same PCB board, which is used for internal installation inside the housing of the electric cylinder.

8. The built-in control drive module of a DC brushed motor electric cylinder according to claim 1, wherein the closed-loop control algorithm is an intelligent PID control algorithm.

9. A control method for a DC brushed motor electric cylinder, applied to the built-in control drive module of the DC brushed motor electric cylinder as described in any one of claims 1 to 8, characterized in that, Includes the following steps: The microcontroller receives external control signals and generates PWM signals based on the external control signals. The PWM signals are used to control the switching state of the integrated H-bridge drive circuit in the power drive module to drive the DC brushed motor to run. Real-time acquisition of current feedback signals and piston rod position feedback signals during the operation of the electric cylinder; The microcontroller calculates the required PWM duty cycle based on the deviation between the target values ​​corresponding to the current feedback signal, the position feedback signal, and the external control signal through a closed-loop control algorithm, and dynamically adjusts the duty cycle of the output PWM signal to precisely control the motor speed, direction, and output torque. The protection circuit monitors the system's operating status in real time and executes corresponding protection actions when it detects overcurrent, overvoltage, or overheating abnormalities.

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