Electro-hydraulic servo actuator controller system

Abstract

The invention belongs to the field of electro-hydraulic servo actuators, particularly relates to an electro-hydraulic servo actuator controller system, and aims to solve the problems that most of existing controllers are of analog structures, namely a large number of analog electronic components are adopted to form an analog control circuit, the parameter adjustment process is tedious, and timely replacement and adjustment of a control algorithm are not facilitated. In order to solve the problem that the prior art is difficult to adapt to various working occasions, the invention provides the following scheme that the system comprises a control unit, the control unit is connected with a power supply unit, a 4G module, an analog-to-digital converter, a current detection unit and a position detection unit, the control unit is an STM32 microprocessor, the 4G module is connected with a cloud server, and the cloud server is connected with a cloud server. According to the electro-hydraulic servo actuator, the overall performance of the electro-hydraulic servo actuator can be improved, rapid positioning of a rotor at any position is achieved, meanwhile, the defect that a motor is out of step is overcome, and the electro-hydraulic servo actuator has the advantages of being high in response speed and high in control precision.

Description

Technical Field

[0001] This invention relates to the field of electro-hydraulic servo actuator technology, and more particularly to an electro-hydraulic servo actuator controller system. Background Technology

[0002] Actuators are common power output devices in motion control systems, widely used in industrial applications such as vibration tables, automatic suspension systems, robots, and marine gangways. An actuator system typically consists of a controller, sensors, a load, and the actuator itself. The controller is the carrier of the control method, responsible for receiving sensor signals and outputting drive signals to excite the actuator. As the control core of an electro-hydraulic servo actuator system, the controller controls the flow rate of the electro-hydraulic servo valve, thereby controlling the position of the actuator. Its performance directly affects the control effect of the actuator system.

[0003] Currently, most controllers are analog in structure, which uses a large number of analog electronic components to form analog control circuits. The process of adjusting parameters is cumbersome, and it is not conducive to timely replacement and adjustment of control algorithms. They are also difficult to adapt to various working environments. To address these issues, we propose an electro-hydraulic servo actuator controller system. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies where controllers are mostly analog structures, i.e., they use a large number of analog electronic components to form analog control circuits, the parameter adjustment process is cumbersome, it is not conducive to timely replacement and adjustment of control algorithms, and it is difficult to adapt to various working environments. Therefore, an electro-hydraulic servo actuator controller system is proposed.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An electro-hydraulic servo actuator controller system includes a control unit connected to a power supply unit, a 4G module, an analog-to-digital converter, a current detection unit, and a position detection unit. The control unit is an STM32 microprocessor. The 4G module is connected to a cloud server. The input terminal of the analog-to-digital converter is connected to a sensor signal interface circuit. The control unit is connected to a drive unit, which is connected to a stepper motor. The drive unit is connected to the current detection unit, and the stepper motor is connected to the position detection unit. The stepper motor is connected to a servo valve, which is connected to an actuator and a laser displacement sensor.

[0007] Preferably, the actuator is connected to a piston displacement sensor, a first chamber pressure sensor, and a second chamber pressure sensor.

[0008] Preferably, the power supply unit provides a DC power output with good performance for the entire controller, the current detection unit detects the magnitude of the two-phase current of the stepper motor, and the position detection unit transmits the position information of the stepper motor rotor and the piston movement position information in real time.

[0009] Preferably, the analog-to-digital converter is used to convert analog signals collected by sensors of a preset category into corresponding digital signals.

[0010] Preferably, the control unit processes various signals that have been converted into digital quantities and performs control algorithm calculations through programming, and outputs control signals to the drive unit.

[0011] Preferably, the laser displacement sensor is used to detect the valve core position, the piston displacement sensor is used to detect the displacement of the piston rod of the actuator, and the first chamber pressure sensor and the second chamber pressure sensor are used to detect the pressure of the two hydraulic chambers of the actuator.

[0012] Preferably, the sensor signal interface circuit is used to connect with multiple preset category sensors, collect corresponding analog signals, and send the analog signals collected by the multiple category sensors to the signal conversion module. The multiple preset category sensors include a proportional electromagnet current sampling resistor, a valve core displacement sensor, a hydraulic cylinder displacement sensor, a hydraulic cylinder speed sensor, and a hydraulic cylinder cavity pressure sensor.

[0013] Preferably, the drive unit drives the stepper motor to rotate, realizing the conversion of control signals into power signals. The control unit outputs digital pulse signals to control the energizing cycle and switching time of the power transistor, thereby changing the magnitude of the two-phase current of the stepper motor and realizing rapid positioning of the stepper motor.

[0014] Preferably, the laser displacement sensor, piston displacement sensor, first cavity pressure sensor, and second cavity pressure sensor are all connected to the sensor signal interface circuit.

[0015] Preferably, the power supply unit provides a stable power supply for the microprocessor, analog-to-digital converter, sensor signal interface circuit, drive unit circuit, position current detection unit circuit, etc.

[0016] The beneficial effects of the electro-hydraulic servo actuator controller system described in this invention are as follows:

[0017] 1. This solution controls the position of the valve core of the electro-hydraulic servo valve by outputting a control signal to the drive unit, and then controls the piston position of the actuator by controlling the output flow of the electro-hydraulic servo valve.

[0018] 2. This solution uses a drive unit to drive a stepper motor to rotate, thereby converting control signals into power signals. The control unit outputs digital pulse signals to control the energizing cycle and switching time of the power transistor, changing the magnitude of the two-phase current of the motor and achieving rapid positioning of the motor.

[0019] This invention can improve the overall performance of electro-hydraulic servo actuators, realize rapid positioning of rotors at any position, and overcome the disadvantage of motor step loss, giving it the advantages of fast response speed and high control accuracy. Attached Figure Description

[0020] Figure 1 This is a structural block diagram of an electro-hydraulic servo actuator controller system proposed in this invention;

[0021] Figure 2 This is a schematic diagram of the structure of an electro-hydraulic servo actuator controller system proposed in this invention;

[0022] Figure 3 This is a schematic diagram of the internal structure of an electro-hydraulic servo actuator controller system proposed in this invention. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0024] Reference Figures 1-3An electro-hydraulic servo actuator controller system includes a control unit connected to a power supply unit, a 4G module, an analog-to-digital converter (ADC), a current detection unit, and a position detection unit. The control unit is an STM32 microprocessor. The 4G module is connected to a cloud server, which is connected to the 4G module circuit via a communication line for data communication. A sensor signal interface circuit is connected to the input of the ADC. The control unit is connected to a drive unit, which is connected to a stepper motor. The drive unit is connected to the current detection unit, and the stepper motor is connected to the position detection unit. The stepper motor is connected to a servo valve, which is connected to an actuator and a laser displacement sensor. The power supply unit provides stable power to the microprocessor, ADC, sensor signal interface circuit, drive unit circuit, and position / current detection unit circuit. The actuator is connected to a piston displacement sensor, a first chamber pressure sensor, and a second chamber pressure sensor. All three sensors are connected to the sensor signal interface circuit. The power supply unit provides a high-performance DC power output to the entire controller. The current detection unit detects the stepper motor's position. The stepper motor's two-phase current is measured, and the position detection unit transmits the rotor's position information and piston's movement position information in real time. The drive unit drives the stepper motor to rotate, realizing the conversion of control signals into power signals. The control unit outputs digital pulse signals to control the power transistor's energizing cycle and switching time, changing the magnitude of the stepper motor's two-phase current to achieve rapid positioning of the stepper motor. The analog-to-digital converter is used to convert analog signals collected by preset category sensors into corresponding digital signals. The sensor signal interface circuit is used to connect to multiple preset category sensors, collect corresponding analog signals, and send the analog signals collected by multiple category sensors to the signal conversion module. The multiple preset category sensors include a proportional electromagnet current sampling resistor, a valve core displacement sensor, a hydraulic cylinder displacement sensor, a hydraulic cylinder speed sensor, and a hydraulic cylinder cavity pressure sensor. The control unit processes the various signals converted to digital quantities and calculates the control algorithm through programming, outputting control signals to the drive unit. Through pre-programmed code, the control unit combines sensor feedback to calculate the control algorithm, which includes a dynamic control algorithm and a state feedback control algorithm. After the algorithm is solved, the control unit outputs a control signal to the drive unit to control the position of the electro-hydraulic servo valve core. Then, by controlling the output flow of the electro-hydraulic servo valve, the position of the piston of the actuator is controlled. The laser displacement sensor is used to detect the position of the valve core, the piston displacement sensor is used to detect the displacement of the piston rod of the actuator, and the first chamber pressure sensor and the second chamber pressure sensor are used to detect the pressure of the two hydraulic chambers of the actuator. Since the data processing is mainly completed in the interrupt routines of each module, the software design mainly focuses on the main program and the interrupt subroutines of modules such as PWM, SP2, ADC, and VART.

[0025] In this embodiment, to improve the control accuracy and response speed of the electro-hydraulic servo actuator, the proposed algorithm is a position-current dual closed-loop control based on current synchronous control. The input signal is sampled by the AD module and then enters the STM32 microprocessor. After data processing, it is converted into the angle through which the stator rotating magnetic field of the stepper motor rotates, thereby changing the current setpoint of the two-phase windings and altering the duty cycle of the PWM wave. The change in duty cycle alters the on / off time of the power transistors in the drive circuit. Since the PWM wave has a high frequency, it can be considered as a change in the transient voltage applied across the two-phase windings, thus changing the current flowing through the two-phase windings. This change in current causes the rotating magnetic field generated within the motor to rotate, driving the motor rotor to rotate. After the magnitude of the two-phase current is detected by the current detection unit, the output voltage is proportional to the current magnitude. After being sampled by the AD module, it enters the STM32 microprocessor to form a current closed loop and perform PID calculations to improve the accuracy and response speed of current control. The rotation angle of the motor rotor is measured by the angular displacement sensor on the back of the stepper motor and communicates with the STM32 microprocessor through the SP2 serial port of the chip. Inside the STM32 microprocessor, it forms a position closed loop with the input signal and performs PID calculations to improve the control accuracy of the motor rotor rotation angle and overcome the disadvantage of stepper motors easily losing steps during operation.

[0026] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An electro-hydraulic servo actuator controller system, comprising a control unit, characterized in that, The control unit is connected to a power supply unit, a 4G module, an analog-to-digital converter, a current detection unit, and a position detection unit. The control unit is an STM32 microprocessor. The 4G module is connected to a cloud server. The input terminal of the analog-to-digital converter is connected to a sensor signal interface circuit. The control unit is connected to a drive unit, which is connected to a stepper motor. The drive unit is connected to the current detection unit, and the stepper motor is connected to the position detection unit. The stepper motor is connected to a servo valve, and the servo valve is connected to an actuator and a laser displacement sensor.

2. The electro-hydraulic servo actuator controller system according to claim 1, characterized in that, The power supply unit provides a stable power supply for the microprocessor, analog-to-digital converter, sensor signal interface circuit, drive unit circuit, and position current detection unit circuit.

3. The electro-hydraulic servo actuator controller system according to claim 2, characterized in that, The actuator is connected to a piston displacement sensor, a first chamber pressure sensor, and a second chamber pressure sensor.

4. The electro-hydraulic servo actuator controller system according to claim 3, characterized in that, The laser displacement sensor, piston displacement sensor, first cavity pressure sensor, and second cavity pressure sensor are all connected to the sensor signal interface circuit.

5. The electro-hydraulic servo actuator controller system according to claim 4, characterized in that, The power supply unit provides a high-performance DC power output for the entire controller, the current detection unit detects the magnitude of the two-phase current of the stepper motor, and the position detection unit transmits the position information of the stepper motor rotor and the piston movement position information in real time.

6. The electro-hydraulic servo actuator controller system according to claim 5, characterized in that, The drive unit drives the stepper motor to rotate, realizing the conversion of control signals into power signals. The control unit outputs digital pulse signals to control the energizing cycle and switching time of the power transistor, thereby changing the magnitude of the two-phase current of the stepper motor and realizing rapid positioning of the stepper motor.

7. The electro-hydraulic servo actuator controller system according to claim 6, characterized in that, The analog-to-digital converter is used to convert analog signals collected by sensors of a preset category into corresponding digital signals.

8. The electro-hydraulic servo actuator controller system according to claim 7, characterized in that, The sensor signal interface circuit is used to connect with multiple preset categories of sensors, collect corresponding analog signals, and send the analog signals collected by the multiple categories of sensors to the signal conversion module. The multiple preset categories of sensors include a proportional electromagnet current sampling resistor, a valve core displacement sensor, a hydraulic cylinder displacement sensor, a hydraulic cylinder speed sensor, and a hydraulic cylinder cavity pressure sensor.

9. The electro-hydraulic servo actuator controller system according to claim 8, characterized in that, The control unit processes various signals that have been converted into digital quantities and performs control algorithm calculations through programming, and outputs control signals to the drive unit.

10. The electro-hydraulic servo actuator controller system according to claim 9, characterized in that, The laser displacement sensor is used to detect the position of the valve core, the piston displacement sensor is used to detect the displacement of the piston rod of the actuator, and the first chamber pressure sensor and the second chamber pressure sensor are used to detect the pressure of the two hydraulic chambers of the actuator.

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