A servo valve control method, system, device and medium

Abstract

This invention provides a servo valve control method, system, device, and medium, relating to the field of servo valve control technology. The method includes receiving a power-on trigger signal and performing a hardware self-test; driving a servo motor to move the valve throughout its stroke range and acquiring real-time valve position data, generating a valve stroke range and position-opening degree mapping relationship; receiving external control commands and matching the command parsing protocol, parsing the commands to obtain the valve target opening degree, converting it into the valve target position based on the position-opening degree mapping relationship, performing limit checks on the valve target position based on the valve stroke range, and outputting the valve target position control quantity; performing closed-loop adjustment calculations on the control quantity, outputting a motor drive signal to the servo driver, and simultaneously outputting a valve position feedback signal, thereby improving valve control accuracy, precisely adapting to various combinations of control signals and feedback signals, and allowing the adjustment stroke to be arbitrarily set throughout the entire stroke, enhancing the flexibility of the valve opening and closing directions.

Description

Technical Field

[0001] This invention relates to the field of servo valve control technology, and in particular to a servo valve control method, system, device and medium. Background Technology

[0002] With the continuous acceleration of industrial automation, modern industrial production places increasingly stringent demands on the position control accuracy, dynamic response speed, and long-term operational stability of actuators. In fields such as petroleum, chemical, power, metallurgy, and urban water supply and drainage, valves, as key components of fluid control, directly impact the safety and efficiency of the entire production system through the accuracy and reliability of their opening regulation. Furthermore, with the rapid development of servo motors, high-precision encoders, and microprocessor technologies, electric actuators have gradually achieved digital and intelligent upgrades. The deep integration of IoT technology and artificial intelligence algorithms is further driving the evolution of actuators towards highly modular, networked remote monitoring, and intelligent fault prediction.

[0003] However, traditional electric actuators generally rely on mechanical transmission structures to achieve simple switching operations. Their control methods are singular and rigid, lacking intelligent adjustment and remote monitoring capabilities. They also suffer from prominent problems such as complex mechanical structures, high maintenance costs, and insufficient safety and reliability, making it difficult to meet the urgent needs of current industrial sites for precise adjustment and remote centralized control of valve openings. Existing servo valve control systems still suffer from limited control accuracy, poor compatibility between control and feedback signals, and inflexible adjustment stroke settings in practical applications, severely restricting their promotion and application in complex and ever-changing industrial scenarios.

[0004] Therefore, it is necessary to provide a servo valve control method, system, device, and medium to solve the above-mentioned technical problems. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a servo valve control method, system, device, and medium, which solves the problems of insufficient valve control accuracy, difficulty in adapting to various combinations of control signals and feedback signals, inability to arbitrarily set the adjustment stroke within the entire stroke, and lack of flexibility in valve opening and closing directions.

[0006] This invention provides a servo valve control method, the method comprising: Receives the power-on trigger signal and performs a system hardware self-test, and outputs a system ready status signal; In response to the system ready status signal, the control system enters the stroke learning mode, drives the servo motor to move the valve through the valve stroke range, and collects the real-time valve position through the absolute encoder to generate the valve stroke range and position-opening mapping relationship; Receive external control commands and match the corresponding command parsing protocol, parse the external control commands based on the command parsing protocol to obtain the target valve opening, convert the target valve opening into the target valve position based on the position-opening mapping relationship, perform over-limit verification on the target valve position based on the valve stroke range, and output the target valve position control quantity. The target valve position control quantity is input to a multi-level servo closed-loop control loop, and closed-loop adjustment calculation is performed in conjunction with the real-time valve position. The motor drive signal is output to the servo driver, and the valve position feedback signal is output synchronously.

[0007] Preferably, the step of receiving the power-on trigger signal, performing a system hardware self-test, and outputting a system ready status signal includes: The system detects the voltage amplitude and ripple coefficient of the power input, determines whether the voltage is within the rated voltage operating range, and outputs the power detection result signal. When the power detection result signal is qualified, the absolute encoder, the servo driver, the operation panel and the communication interface are sequentially tested for connectivity, and a hardware self-test status code is generated. Obtain the hardware self-test pass threshold, compare the hardware self-test status code with the hardware self-test pass threshold, if the hardware self-test status code is the same as the hardware self-test pass threshold, output the system ready status signal, and synchronously load and send the default configuration parameters stored in the non-volatile memory, including control mode, reference dead zone value and torque upper limit threshold.

[0008] Preferably, in response to the system ready state signal, the control system enters a stroke learning mode, drives the servo motor to move the valve through the valve stroke range, and collects the real-time valve position through an absolute encoder to generate a valve stroke range and position-opening mapping relationship, including: In response to the system ready status signal, the system receives the stroke learning trigger command, controls the system to enter the stroke learning mode, drives the servo motor to drive the valve to the closing direction at a preset low speed, collects the motor torque through the servo driver, and simultaneously collects the real-time valve position through the absolute encoder. When the motor torque is detected to reach the calibrated torque threshold and the duration exceeds the calibrated duration, the current valve position value collected by the absolute encoder is locked and recorded as the closing stroke endpoint. The servo motor is driven to move the valve in the opening direction at the preset low speed. The motor torque is collected by the servo driver, and the real-time valve position is collected by the absolute encoder at the same time. When the motor torque is detected to reach the calibrated torque threshold and the duration exceeds the preset duration, the current valve position value collected by the absolute encoder is locked and recorded as the opening stroke endpoint; The valve stroke range is determined based on the closing stroke endpoint and the opening stroke endpoint, and a linear correspondence is established between the real-time valve position and valve opening degree collected by the absolute encoder, generating the position-opening degree mapping relationship.

[0009] Preferably, the steps of receiving external control commands and matching corresponding command parsing protocols, parsing the external control commands based on the command parsing protocols to obtain the target valve opening, converting the target valve opening into a target valve position based on the position-opening mapping relationship, performing limit checks on the target valve position based on the valve stroke range, and outputting the target valve position control quantity include: The signal type of the external control command is detected, and the command parsing protocol corresponding to CAN communication, analog quantity, switch quantity and fieldbus is matched to identify the valid data segment of the external control command. Based on the instruction parsing protocol obtained by matching, the valid data segment is parsed, and the parsed valid data segment is subjected to first-order low-pass filtering and range conversion to obtain the target valve opening. Based on the position-opening degree mapping relationship, the target valve opening degree is converted into the target valve position through linear interpolation. The valve target position is checked for exceeding limits based on the valve stroke range. If the valve target position value is within the valve stroke range, the valve target position value is output as the valve target position control quantity. If the valve target position value is less than the valve position endpoint value corresponding to the closing stroke endpoint of the valve stroke range, the valve target position value is clamped to the valve position endpoint value corresponding to the closing stroke endpoint and output as the valve target position control quantity. If the valve target position value is greater than the valve position endpoint value corresponding to the opening stroke endpoint of the valve stroke range, the valve target position value is clamped to the valve position endpoint value corresponding to the opening stroke endpoint and output as the valve target position control quantity.

[0010] Preferably, the step of inputting the valve target position control quantity to a multi-level servo closed-loop control loop, performing closed-loop adjustment calculations in conjunction with the real-time valve position, outputting a motor drive signal to the servo driver, and synchronously outputting a valve position feedback signal includes: The target valve position control quantity is input to the multi-level servo closed-loop control loop, the position deviation between the target valve position control quantity and the real-time valve position is calculated, the position deviation is input to the position loop controller, and the target speed control quantity is output. calculating a rotation speed deviation between the target rotation speed control amount and a real-time rotation speed feedback amount of the servo motor; inputting the rotation speed deviation into a speed loop controller to generate an initial torque control amount; superimposing the initial torque control amount with a friction torque compensation amount, and outputting a target torque control amount; when the position deviation is smaller than a preset buffer distance threshold, determining that the valve enters a buffering interval, calculating a ratio of the position deviation to a total length of the buffer distance to obtain a deceleration coefficient; proportionally scaling the target torque control amount based on the deceleration coefficient to generate a buffering torque control instruction; generating a PWM driving signal with a corresponding duty cycle based on the buffering torque control instruction as the motor driving signal, and outputting the PWM driving signal to the servo driver; collecting a current valve position, converting the current valve position into a feedback signal format matched with the external control instruction, and synchronously outputting the valve position feedback signal.

[0011] preferably, the step of inputting the valve target position control amount into the multi-stage servo closed-loop control loop, calculating a position deviation between the valve target position control amount and the real-time valve position, inputting the position deviation into a position loop controller, and outputting a target rotation speed control amount comprises: inputting the valve target position control amount into the multi-stage servo closed-loop control loop, calculating a position deviation e(k) between the valve target position control amount at a current moment k and the real-time valve position, and constructing a non-singular fast terminal sliding mode surface s(k), wherein a corresponding calculation formula is as follows: ; in the formula, is a positive coefficient of the non-singular fast terminal sliding mode surface; p and q are power parameters of the non-singular fast terminal sliding mode surface, both are positive odd numbers, and satisfy p>q>0; calculating a sliding mode reaching law control component by adopting a hyperbolic tangent composite power reaching law based on the non-singular fast terminal sliding mode surface s(k) , wherein a corresponding calculation formula is as follows: ; in the formula, is a positive coefficient of the hyperbolic tangent composite power reaching law; m and n are power parameters of the hyperbolic tangent composite power reaching law, both are positive odd numbers, and satisfy m<n; T is a control period; tanh( ) is a hyperbolic tangent function; Based on the position deviation, the servo motor, valve transmission mechanism, and valve are equivalent to a second-order rigid body rotation structure, and an equivalent dynamic model of the valve is established. Based on the sliding mode invariance principle, the rate of change of the non-singular fast terminal sliding surface is set to 0, and substituted into the equivalent dynamic model of the valve to obtain the equivalent control components. The equivalent control components are superimposed with the sliding mode reaching law control components to obtain the position loop output increment. Obtain the position loop output at the previous time k-1, and add it to the position loop output increment at the current time k to obtain the position loop output at the current time k; The position loop output at the current time k is subjected to speed limiting processing, and the target speed control quantity is output.

[0012] Preferably, the process of generating the frictional torque compensation includes: A friction observer is constructed based on the LuGre dynamic friction model to estimate the friction torque compensation amount of the valve transmission mechanism in real time. The corresponding calculation formula is as follows: ; ; ; In the formula, z is the equivalent deformation of the bristles of the valve transmission mechanism; The rate of change of the equivalent deformation of the bristles in the valve transmission mechanism; This refers to the real-time angular velocity of the servo motor. Stribeck characteristic velocity; These are the bristle stiffness coefficient, bristle damping coefficient, and viscous friction coefficient of the LuGre dynamic friction model, respectively. The Coulomb friction torque of the valve transmission mechanism; This represents the maximum static friction torque of the valve transmission mechanism. This is the Stribeck effect function.

[0013] A servo valve control system, the system comprising: The ready module is used to receive the power-on trigger signal, perform system hardware self-test, and output the system ready status signal; The drive module is used to respond to the system ready state signal, control the system to enter the stroke learning mode, drive the servo motor to drive the valve to traverse the valve stroke range, and collect the real-time valve position through the absolute encoder to generate the valve stroke range and position-opening mapping relationship. The conversion module is used to receive external control commands and match the corresponding command parsing protocol, parse the external control commands based on the command parsing protocol to obtain the target valve opening, convert the target valve opening into the target valve position based on the position-opening mapping relationship, perform over-limit verification on the target valve position based on the valve stroke range, and output the target valve position control quantity. The output module is used to input the target valve position control quantity to a multi-level servo closed-loop control loop, perform closed-loop adjustment calculations in conjunction with the real-time valve position, output a motor drive signal to the servo driver, and synchronously output a valve position feedback signal.

[0014] An electronic device includes a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor performs the steps of a servo valve control method as described in any of the above.

[0015] A readable storage medium storing a computer program, which, when executed by a processor, is used to implement the steps of a servo valve control method as described in any of the above claims.

[0016] Compared with related technologies, the servo valve control method, system, equipment, and medium provided by the present invention have the following beneficial effects: This invention receives a power-on trigger signal and performs a system hardware self-test, outputting a system ready status signal. In response to this signal, the control system enters a stroke learning mode, driving a servo motor to move the valve throughout its stroke range. A real-time valve position is acquired using an absolute encoder, generating a mapping relationship between the valve stroke range and the position-opening degree. External control commands are received and matched with the corresponding command parsing protocol. The external control commands are parsed using this protocol to obtain the target valve opening. Based on the position-opening degree mapping relationship, the target valve opening is converted into the target valve position. The target valve position is checked for exceeding limits based on the valve stroke range, and the target valve position control quantity is output. This target valve position control quantity is input to a multi-level servo closed-loop control loop. Combined with the real-time valve position, closed-loop adjustment calculations are performed, outputting a motor drive signal to the servo driver and simultaneously outputting a valve position feedback signal. This improves valve control accuracy, precisely adapts to various combinations of control and feedback signals, and allows for arbitrary setting of the adjustment stroke throughout the entire stroke, enhancing the flexibility of the valve's opening and closing directions.

[0017] This invention, employing servo drive technology and an absolute encoder, significantly improves the accuracy and operational stability of valve opening control, effectively suppressing system errors and hysteresis, and meeting the requirements of high-precision industrial control scenarios. It supports flexible combinations of various types of control and feedback signals, and is widely adaptable to communication protocols and interface standards of different control system architectures, greatly enhancing the equipment's versatility and field compatibility, and reducing system integration difficulty. This invention allows for arbitrary setting of the effective adjustment stroke within the entire mechanical stroke range of the valve, and supports custom configuration of the valve opening and closing directions, greatly improving the convenience of field installation and adaptability to complex operating conditions. Simultaneously, this invention can accurately match thrust according to different valve types and operating loads, and possesses good environmental adaptability, operating stably within a wide temperature range, ensuring equipment reliability and service life. This invention achieves precise overload protection through intelligent motor control strategies, effectively avoiding mechanical damage and significantly reducing equipment failure rates. In addition, this invention fully supports local manual control, infrared remote control and various industrial bus communication control methods, making it convenient and flexible to operate, easy to debug on-site, configure parameters and remotely centrally monitor, and significantly improve the overall operating efficiency, maintenance convenience and management intelligence level of industrial automation systems. Attached Figure Description

[0018] Figure 1 A flowchart of a servo valve control method provided in an embodiment of the present invention; Figure 2 A system block diagram of a servo valve control system provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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] like Figure 1 The diagram shown is a flowchart of a servo valve control method provided in an embodiment of the present invention. Figure 1The execution subject of the method shown can be a software and / or hardware device. The execution subject of this invention can include, but is not limited to, at least one of the following: user equipment, network equipment, etc. User equipment can include, but is not limited to, computers, smartphones, personal digital assistants (PDAs), and the aforementioned electronic devices. Network equipment can include, but is not limited to, a single network server, a server group consisting of multiple network servers, or a cloud based on cloud computing consisting of a large number of computers or network servers. Cloud computing is a type of distributed computing, consisting of a super virtual computer composed of a group of loosely coupled computers. This embodiment does not limit this. Steps S1 to S4 are detailed as follows: S1 receives the power-on trigger signal and performs a system hardware self-test, outputting a system ready status signal.

[0021] The process of receiving the power-on trigger signal, performing a system hardware self-test, and outputting a system ready status signal includes: The system detects the voltage amplitude and ripple coefficient of the power input, determines whether the voltage is within the rated voltage operating range, and outputs the power detection result signal. When the power detection result signal is qualified, the absolute encoder, the servo driver, the operation panel and the communication interface are sequentially tested for connectivity, and a hardware self-test status code is generated. Obtain the hardware self-test pass threshold, compare the hardware self-test status code with the hardware self-test pass threshold, if the hardware self-test status code is the same as the hardware self-test pass threshold, output the system ready status signal, and synchronously load and send the default configuration parameters stored in the non-volatile memory, including control mode, reference dead zone value and torque upper limit threshold.

[0022] After the system is powered on, the voltage amplitude and ripple coefficient of the power input port are sampled in real time. The sampled voltage amplitude is compared with the rated voltage operating range, and it is determined whether the ripple coefficient is within the preset allowable fluctuation range. A power detection result signal is generated to indicate whether the current power quality meets the system startup requirements.

[0023] When the power supply detection signal indicates that the power supply status is qualified, the system performs connectivity self-tests on the absolute encoder, servo driver, operation panel, and communication interface in a preset order. The connectivity self-test includes at least verifying the electrical connection status of each hardware module, checking the signal integrity of the communication link, and confirming the normal functional response of each module. The self-test results of each module are then encoded and integrated to generate a hardware self-test status code.

[0024] The system reads the pre-stored hardware self-test pass threshold and compares the hardware self-test status code with the hardware self-test pass threshold bit by bit. If the hardware self-test status code matches the hardware self-test pass threshold, the system hardware self-test is deemed to have passed, and a system ready status signal is output, indicating that the system has completed initialization and is in a ready-to-run state. Simultaneously with outputting the system ready status signal, the system retrieves default configuration parameters from non-volatile memory, including at least the control mode, reference dead zone value, and torque upper limit threshold. These default configuration parameters are then loaded into the system running register and distributed to the corresponding control modules, including the position loop controller, speed loop controller, servo driver, main control communication module, and operation panel display control module.

[0025] The system comprises the following components: a position loop controller, a speed loop controller, and a main control module. The position loop controller receives the reference dead zone value to determine the effective adjustment range of the position deviation and prevent high-frequency oscillations near the target position. The speed loop controller receives the torque upper limit threshold to limit the output torque of the servo motor and prevent overload damage to the valve transmission mechanism under abnormal operating conditions. The servo driver receives control mode parameters and the torque upper limit threshold to configure the output mode of the motor drive signal and the torque output boundary, thereby achieving drive control of the servo motor. The main control communication module receives control mode parameters to configure the instruction parsing protocol and communication interface working mode between the system and external control devices. The operation panel display control module receives control mode parameters to configure the display status and operation enable logic of the local human-machine interface.

[0026] After the system hardware self-test is passed, each control module synchronously receives and loads the default configuration parameters stored in the non-volatile memory to achieve system initialization and ensure that the multi-level servo closed-loop control loop and external communication interface enter the ready-to-run state according to the preset operating conditions.

[0027] S2, in response to the system ready state signal, the control system enters the stroke learning mode, drives the servo motor to drive the valve to traverse the valve stroke range, and collects the real-time valve position through the absolute encoder to generate the valve stroke range and position-opening mapping relationship.

[0028] In response to the system readiness signal, the control system enters the stroke learning mode, drives the servo motor to move the valve through the valve stroke range, and collects the real-time valve position through an absolute encoder to generate a valve stroke range and position-opening mapping relationship, including: In response to the system ready status signal, the system receives the stroke learning trigger command, controls the system to enter the stroke learning mode, drives the servo motor to drive the valve to the closing direction at a preset low speed, collects the motor torque through the servo driver, and simultaneously collects the real-time valve position through the absolute encoder. When the motor torque is detected to reach the calibrated torque threshold and the duration exceeds the calibrated duration, the current valve position value collected by the absolute encoder is locked and recorded as the closing stroke endpoint. The servo motor is driven to move the valve in the opening direction at the preset low speed. The motor torque is collected by the servo driver, and the real-time valve position is collected by the absolute encoder at the same time. When the motor torque is detected to reach the calibrated torque threshold and the duration exceeds the preset duration, the current valve position value collected by the absolute encoder is locked and recorded as the opening stroke endpoint; The valve stroke range is determined based on the closing stroke endpoint and the opening stroke endpoint, and a linear correspondence is established between the real-time valve position and valve opening degree collected by the absolute encoder, generating the position-opening degree mapping relationship.

[0029] After outputting a system ready status signal, the system receives a stroke learning trigger command and switches the system operating mode to stroke learning mode. Stroke learning mode is used to automatically calibrate the limit positions of the valve's mechanical stroke during initial installation or re-commissioning, establishing a quantitative mapping relationship between the absolute encoder output value and the valve opening. Depending on the valve structure, stroke learning mode is suitable for partial-turn and multi-turn valves; depending on the operating method, stroke learning mode includes manual and automatic learning modes. In automatic learning mode, the system automatically controls the servo motor to run to the stroke endpoint; in manual learning mode, the operator controls the servo motor to run to the stroke endpoint via the control panel.

[0030] In stroke learning mode, the system outputs a low-speed operation command to the servo driver, driving the servo motor to move the valve towards the closing direction at a preset low speed. The preset low speed is a rotational speed lower than the valve's rated operating speed, used to reduce mechanical shock during the stroke end calibration process. During the valve's movement towards the closing direction, the servo driver acquires the servo motor's output torque in real time, and the absolute encoder synchronously acquires the valve's real-time angular or linear displacement, feeding back the torque and position data to the system.

[0031] The system compares the real-time collected motor torque with a pre-stored calibrated torque threshold, while simultaneously monitoring the cumulative duration for which the torque continuously exceeds the calibrated torque threshold. When the motor torque reaches the calibrated torque threshold and the duration exceeds the calibrated time, it determines that the valve has reached the mechanical limit position in the closing direction. The system locks the valve position value currently output by the absolute encoder and records it as the end point of the closing stroke. The calibrated torque threshold is set according to the valve type and transmission mechanism characteristics to distinguish between normal operating resistance and mechanical end point resistance.

[0032] After completing the calibration of the closed stroke endpoint, the system outputs a low-speed operation command to the servo driver again, driving the servo motor to move the valve in the opening direction at a preset low speed. During the valve's movement in the opening direction, the servo driver continuously acquires the motor torque, and the absolute encoder synchronously acquires the real-time valve position and feeds the data back to the system.

[0033] When the motor torque is detected to reach the calibrated torque threshold and the duration exceeds the preset duration, it is determined that the valve has reached the mechanical limit position in the opening direction. The system locks the valve position value currently output by the absolute encoder and records it as the end point of the opening stroke.

[0034] The system calculates the valve stroke range based on the recorded closing and opening stroke endpoints. The valve stroke range is the total displacement of the valve between its mechanical limits in the closing and opening directions. The system establishes a linear correspondence between the real-time valve position acquired by the absolute encoder and the valve opening degree. It linearly maps the absolute position value output by the encoder to the opening degree range of 0% to 100%, generating a position-opening degree mapping relationship and storing it in non-volatile memory for subsequent closed-loop control. For partially rotary valves, the position-opening degree mapping relationship corresponds to angle parameters; for multi-turn valves, it corresponds to the number of turns parameter.

[0035] S3, receive external control commands and match the corresponding command parsing protocol, parse the external control commands based on the command parsing protocol to obtain the valve target opening degree, convert the valve target opening degree into the valve target position based on the position-opening degree mapping relationship, perform limit verification on the valve target position based on the valve stroke range, and output the valve target position control quantity.

[0036] The process involves receiving external control commands and matching them with corresponding command parsing protocols, parsing the external control commands based on the command parsing protocols to obtain the target valve opening, converting the target valve opening into a target valve position based on the position-opening mapping relationship, performing limit checks on the target valve position based on the valve stroke range, and outputting a target valve position control quantity, including: The signal type of the external control command is detected, and the command parsing protocol corresponding to CAN communication, analog quantity, switch quantity and fieldbus is matched to identify the valid data segment of the external control command. Based on the instruction parsing protocol obtained by matching, the valid data segment is parsed, and the parsed valid data segment is subjected to first-order low-pass filtering and range conversion to obtain the target valve opening. Based on the position-opening degree mapping relationship, the target valve opening degree is converted into the target valve position through linear interpolation. The valve target position is checked for exceeding limits based on the valve stroke range. If the valve target position value is within the valve stroke range, the valve target position value is output as the valve target position control quantity. If the valve target position value is less than the valve position endpoint value corresponding to the closing stroke endpoint of the valve stroke range, the valve target position value is clamped to the valve position endpoint value corresponding to the closing stroke endpoint and output as the valve target position control quantity. If the valve target position value is greater than the valve position endpoint value corresponding to the opening stroke endpoint of the valve stroke range, the valve target position value is clamped to the valve position endpoint value corresponding to the opening stroke endpoint and output as the valve target position control quantity.

[0037] After entering remote control mode, the system performs signal type detection on the external control commands input to the ports. The signal types include at least CAN communication signals, analog signals, digital signals, and fieldbus signals. Based on the detected signal type, the system invokes the corresponding command parsing protocol, which includes at least the CAN communication protocol, analog range conversion protocol, digital status mapping protocol, and fieldbus communication protocol. The system extracts valid data segments from the external control commands according to the frame format or signal specifications defined by the command parsing protocol.

[0038] Based on the command parsing protocol obtained through matching, the system performs protocol parsing on the valid data segments. For analog signals, the system performs first-order low-pass filtering on the sampled values ​​corresponding to current-type or voltage-type control signals to remove high-frequency noise interference during signal transmission. Then, range conversion is performed to map the filtered sampled values ​​to the valve opening range of 0% to 100%, obtaining the target valve opening. For CAN communication signals and fieldbus signals, the system extracts the target opening command data from the communication frame and obtains the target valve opening after first-order low-pass filtering and range conversion. For digital signals, the system determines the corresponding target valve opening based on the switch state mapping relationship.

[0039] The system calls the position-opening mapping relationship stored in non-volatile memory. This mapping relationship represents the linear correspondence between the absolute encoder position value and the valve opening established during the travel learning phase. Based on this mapping relationship, the system converts the target valve opening into the target valve position in the absolute encoder dimension through linear interpolation.

[0040] The system reads the valve stroke range recorded during the stroke learning phase. The valve stroke range is defined by the closing stroke endpoint and the opening stroke endpoint. The target valve position is compared with the valve stroke range, and an over-limit check is performed. If the target valve position value is between the closing stroke endpoint and the opening stroke endpoint, i.e., within the valve stroke range, the target valve position value is directly output as the target valve position control quantity.

[0041] If the valve target position value is less than the valve position endpoint value corresponding to the closing stroke endpoint, it is determined that the valve target position has exceeded the closing direction limit. The valve target position value is forcibly limited to the valve position endpoint value corresponding to the closing stroke endpoint, and the clamped value is used as the valve target position control quantity output.

[0042] If the valve target position value is greater than the valve position endpoint value corresponding to the opening stroke endpoint, it is determined that the valve target position has exceeded the opening direction limit. The valve target position value is forcibly limited to the valve position endpoint value corresponding to the opening stroke endpoint, and the clamped value is used as the valve target position control quantity output.

[0043] S4, input the valve target position control quantity to the multi-level servo closed-loop control loop, perform closed-loop adjustment calculation in combination with the real-time valve position, output motor drive signal to servo driver, and synchronously output valve position feedback signal.

[0044] The process of inputting the target valve position control quantity into a multi-level servo closed-loop control loop, performing closed-loop adjustment calculations in conjunction with the real-time valve position, outputting a motor drive signal to the servo driver, and synchronously outputting a valve position feedback signal includes: The target valve position control quantity is input to the multi-level servo closed-loop control loop, the position deviation between the target valve position control quantity and the real-time valve position is calculated, the position deviation is input to the position loop controller, and the target speed control quantity is output. Calculate the speed deviation between the target speed control quantity and the real-time speed feedback quantity of the servo motor; input the speed deviation quantity to the speed loop controller to generate the initial torque control quantity; superimpose the friction torque compensation quantity on the initial torque control quantity to output the target torque control quantity; When the position deviation is less than a preset buffer distance threshold, it is determined that the valve has entered the buffer zone. The ratio of the position deviation to the total length of the buffer distance is calculated to obtain the deceleration coefficient. Based on the deceleration coefficient, the target torque control quantity is scaled proportionally to generate a buffer torque control command. Based on the buffer torque control command, a PWM drive signal with a corresponding duty cycle is generated as the motor drive signal and output to the servo driver. The current valve position is acquired and converted into a feedback signal format that matches the external control command, and the valve position feedback signal is output synchronously.

[0045] The system inputs the target valve position control value to a multi-level servo closed-loop control loop. It calculates the difference between the target valve position control value and the real-time valve position acquired by the absolute encoder to obtain the position deviation, which characterizes the displacement difference between the current valve position and the target position. The sign of the deviation indicates the valve's adjustment direction. The position deviation is then input to the position loop controller, which performs closed-loop regulation based on a non-singular fast terminal sliding mode control strategy. By constructing a sliding surface and a reaching law, the system achieves rapid convergence of the position deviation and avoids control singularities, outputting the target speed control value. Furthermore, the target speed control value is subjected to speed limiting to constrain the maximum operating speed of the servo motor and prevent overspeed operation.

[0046] The system calculates the difference between the target speed control value and the real-time speed feedback value of the servo motor to obtain the speed deviation. The real-time speed feedback value is acquired and fed back by the servo driver, representing the actual rotational angular velocity of the servo motor. The speed deviation value is input to the speed loop controller, which performs closed-loop adjustment calculations to generate the initial torque control value. To suppress nonlinear friction interference in the valve transmission mechanism, a friction observer is constructed based on the LuGre dynamic friction model. Based on the real-time angular velocity of the servo motor and the characteristics of the transmission mechanism, the friction torque compensation value of the valve transmission mechanism is estimated in real time. The friction torque compensation value is superimposed on the initial torque control value to obtain the target torque control value, thus offsetting the impact of friction nonlinearity on control accuracy.

[0047] The system compares the position deviation with a preset buffer distance threshold. When the absolute value of the position deviation is less than the preset buffer distance threshold, the valve is determined to have entered the buffer zone, at which point the valve approaches the target stroke endpoint. The ratio of the position deviation to the total buffer distance is calculated as a deceleration coefficient, with a value ranging from 0 to 1. Based on the deceleration coefficient, the target torque control quantity is proportionally scaled to generate a buffer torque control command, causing the output torque of the servo motor to gradually decrease as the valve approaches the target position. The buffer torque control command is pulse-width modulated (PWM) to generate a PWM drive signal with a corresponding duty cycle. The PWM drive signal is output to the servo driver, which adjusts the output current according to the PWM duty cycle to drive the servo motor to decelerate, allowing the valve to smoothly approach the target position and reducing mechanical shock and vibration. The preset buffer distance threshold and the total buffer distance are set based on the valve's mechanical characteristics, the transmission mechanism's inertia, and operating conditions.

[0048] While outputting the motor drive signal, the system collects the current valve position through the absolute encoder, and the current valve position is the real-time absolute position value output by the absolute encoder. The position-opening mapping relationship stored in the non-volatile memory is called to convert the current valve position into a corresponding valve opening value. According to the feedback signal format matched with the external control instruction, the valve opening value is subjected to signal conversion and protocol encapsulation, and the valve position feedback signal is synchronously output to the external control device. Wherein, the feedback signal format corresponds to the signal type of the external control instruction, and at least includes CAN communication format, analog format or fieldbus format, so as to ensure protocol consistency between the control signal and the feedback signal.

[0049] Inputting the valve target position control quantity into the multi-stage servo closed-loop control loop, calculating the position deviation between the valve target position control quantity and the real-time valve position, and inputting the position deviation to the position loop controller to output the target speed control quantity comprises: Inputting the valve target position control quantity into the multi-stage servo closed-loop control loop, calculating the position deviation e(k) between the valve target position control quantity and the real-time valve position at the current moment k, and constructing a non-singular fast terminal sliding mode surface s(k), the corresponding calculation formula is as follows: ; In the formula, is a positive coefficient of the non-singular fast terminal sliding mode surface; p and q are power parameters of the non-singular fast terminal sliding mode surface, both are positive odd numbers, satisfying p>q>0; A hyperbolic tangent composite power reaching law is adopted, and the sliding mode reaching law control component is calculated based on the non-singular fast terminal sliding mode surface s(k) , the corresponding calculation formula is as follows: ; In the formula, is a positive coefficient of the hyperbolic tangent composite power reaching law; m and n are power parameters of the hyperbolic tangent composite power reaching law, both are positive odd numbers, satisfying m<n; T is the control period; tanh( ) is the hyperbolic tangent function; Based on the position deviation, the servo motor, the valve transmission mechanism and the valve are equivalently modeled as a second-order rigid body rotation structure, and a valve equivalent dynamic model is established; based on the sliding mode invariance principle, the change rate of the non-singular fast terminal sliding mode surface is set to 0, which is substituted into the valve equivalent dynamic model to solve and obtain the equivalent control component; the equivalent control component is superimposed with the sliding mode reaching law control component to obtain the position loop output increment; Acquiring the position loop output at the previous moment k-1, and superimposing the position loop output increment at the current moment k to obtain the position loop output at the current moment k; The position loop output at the current time k is subjected to speed limiting processing, and the target speed control quantity is output.

[0050] The position loop controller, as the outermost loop of the multi-level servo closed-loop control circuit, receives the target valve position control signal and the real-time valve position feedback from the absolute encoder after signal processing. The target valve position control signal characterizes the desired absolute valve position after limit verification, while the real-time valve position characterizes the actual absolute valve position at the current moment. The position loop controller performs real-time difference calculation between the target valve position control signal and the real-time valve position to obtain the position deviation within the current control cycle. The sign of the position deviation indicates the valve's adjustment direction, and its absolute value reflects the degree of deviation between the current position and the target position.

[0051] The position loop controller constructs a non-singular fast terminal sliding surface based on the position deviation. This non-singular fast terminal sliding surface introduces power-law combination terms into the traditional linear sliding surface, enabling faster convergence when the system state is far from the equilibrium position compared to linear sliding mode. Simultaneously, parameter constraints avoid control singularities that may occur in traditional terminal sliding mode control, ensuring the control law is continuously solvable across the entire state space. The positive coefficients of the non-singular fast terminal sliding surface are used to adjust the curvature characteristics of the sliding surface, while the power-law parameters are all positive odd numbers, used to balance the dynamic response speed and steady-state control accuracy of the system, meeting the industrial requirements for speed, no overshoot, and robustness in valve position control.

[0052] The position loop controller employs a hyperbolic tangent composite power-law approach law to calculate the sliding mode approach law control components. This law combines the bounded saturation characteristics of the hyperbolic tangent function with the rapid convergence of the power term. When the sliding surface is far from the origin, it provides a larger approach velocity to shorten the settling time; when the sliding surface approaches the origin, it automatically reduces the approach velocity to weaken the switching gain. This approach law effectively suppresses high-frequency chattering, a common problem in traditional sliding mode control, while ensuring finite-time convergence of the sliding surface, thus reducing mechanical impact and wear on the valve transmission mechanism. The positive coefficients and power parameters of the hyperbolic tangent composite power-law approach law are all positive odd numbers, and the control period ensures the feasibility and real-time performance of the approach law in the digital controller.

[0053] Based on the position deviation, the system treats the servo motor, valve transmission mechanism, and valve load as an equivalent second-order rigid body rotational structure, establishing an equivalent dynamic model of the valve. This model uniformly converts the rotor inertia of the servo motor, the equivalent rotational inertia of the reduction mechanism, and the equivalent rotational inertia of the valve core and fluid load to obtain the total equivalent rotational inertia of the system. Bearing friction, seal friction, and fluid resistance are uniformly converted into equivalent damping coefficients. The motor's electromagnetic torque is used as the drive input, and the external load torque and the aforementioned friction torque compensation are used as the comprehensive disturbance input. The valve equivalent dynamic model uses the valve's angular or linear displacement as the output and the motor's driving torque as the input, describing the second-order dynamic differential relationship between the valve position and the motor's driving torque.

[0054] Based on the principle of sliding mode invariance, the system sets the rate of change of the non-singular fast-terminal sliding surface to 0. Substituting the sliding conditions into the valve's equivalent dynamic model, the equivalent control components are obtained through algebraic operations. These equivalent control components represent the ideal control input required to maintain the system state on the sliding surface. They are used to compensate for the system's equivalent inertia, equivalent damping, and the combined load disturbance, ensuring that the position deviation converges to 0 according to the preset sliding dynamic characteristics. The solution for the equivalent control components depends on the parameter identification results of the valve's equivalent dynamic model, and the parameters include at least the total equivalent moment of inertia and the equivalent damping coefficient.

[0055] The system vector-superimposes the equivalent control component and the sliding mode reaching law control component to obtain the position loop output increment within the current control cycle. The equivalent control component is used to maintain the sliding mode motion and suppress known disturbances, while the sliding mode reaching law control component is used to drive the system state to rapidly approach the sliding surface. The combined effect of the two causes the valve position to converge to the target position within a finite time. The position loop output increment characterizes the control quantity adjustment value of the current control cycle relative to the previous control cycle, and its dimension is rotational speed or angular velocity, reflecting the magnitude of the correction of the position loop controller's command to the speed loop controller.

[0056] The system reads the stored position loop output from the previous control cycle and adds it discretely with the position loop output increment calculated for the current control cycle to obtain the position loop output for the current control cycle. This eliminates steady-state position deviations under constant load disturbances and frictional nonlinearity, improving the valve's final positioning accuracy and ensuring that the control precision meets the high-precision requirements of industrial automation. The position loop output from the previous control cycle is stored in the controller's running register and updated at the end of each control cycle, providing accurate initial values ​​for the integral calculation of the next control cycle and achieving smooth recursion of the control quantity.

[0057] The position loop output of the current control cycle is subject to speed limiting. This speed limiting is based on the servo motor's rated maximum speed, the mechanical strength constraints of the valve's transmission mechanism, and operational safety requirements, restricting the position loop output to the maximum permissible speed range. When the position loop output exceeds the positive maximum speed limit, it is forcibly constrained to that limit; conversely, when the position loop output is below the negative maximum speed limit, it is forcibly constrained to that limit. This prevents the servo motor from overspeeding when position deviations are large, avoiding damage to the motor and transmission mechanism due to mechanical overload, while ensuring the safety and reliability of the valve throughout its entire stroke adjustment process.

[0058] After speed limiting processing, the position loop controller outputs the target speed control value to the speed loop controller. This target speed control value, as the final output of the position loop controller, is input to the inner loop of the multi-level servo closed-loop control circuit, i.e., the speed loop controller, as the setpoint for the speed loop. The position loop controller and the speed loop controller are cascaded and coupled through the target speed control value. The outer loop is used to eliminate position deviations and generate speed commands, while the inner loop is used to track speed commands and generate torque commands, forming a nested closed-loop control structure. The sign of the target speed control value indicates the rotation direction of the servo motor, and its absolute value indicates the target speed of the servo motor.

[0059] The process of generating the frictional torque compensation includes: A friction observer is constructed based on the LuGre dynamic friction model to estimate the friction torque compensation amount of the valve transmission mechanism in real time. The corresponding calculation formula is as follows: ; ; ; In the formula, z is the equivalent deformation of the bristles of the valve transmission mechanism; The rate of change of the equivalent deformation of the bristles in the valve transmission mechanism; This refers to the real-time angular velocity of the servo motor. Stribeck characteristic velocity; These are the bristle stiffness coefficient, bristle damping coefficient, and viscous friction coefficient of the LuGre dynamic friction model, respectively. The Coulomb friction torque of the valve transmission mechanism; This represents the maximum static friction torque of the valve transmission mechanism. This is the Stribeck effect function.

[0060] To suppress nonlinear frictional interference in the valve transmission mechanism, the system constructs a friction observer based on the LuGre dynamic friction model to estimate the frictional torque compensation of the valve transmission mechanism in real time.

[0061] The LuGre dynamic friction model equates the contacting kinematic pairs in a valve transmission mechanism to a bristle-like contact surface with random elasticity. The bristle-like equivalent deformation describes the cumulative elastic deformation effect of the micro-protrusions on the contact surface under tangential force. The bristle-like equivalent deformation is the state variable of the friction observer, characterizing the degree of elastic energy storage at the contact interface during the pre-sliding stage. The rate of change of the bristle-like equivalent deformation characterizes the dynamic rate of change of elastic deformation, determined by the real-time angular velocity of the servo motor, the bristle-like equivalent deformation, the Stribeck effect function, and the bristle stiffness coefficient.

[0062] The real-time angular velocity of the servo motor is acquired by the speed detection unit built into the servo driver and fed back to the friction observer. The Stribeck characteristic velocity is the critical angular velocity parameter in the Stribeck curve where the friction torque transitions from the maximum static friction torque to the Coulomb friction torque. Its value is determined based on the material properties, surface roughness, and lubrication conditions of the valve transmission mechanism.

[0063] The Stribeck effect function is calculated based on the real-time angular velocity and Stribeck characteristic velocity of the servo motor. It describes the negative slope phenomenon when the friction characteristics transition from static friction to dynamic friction. When the absolute value of the real-time angular velocity of the servo motor is less than the Stribeck characteristic velocity, the output value of the Stribeck effect function lies between the maximum static friction torque and the Coulomb friction torque, reflecting the condition where static friction dominates under boundary lubrication or mixed lubrication conditions. When the absolute value of the real-time angular velocity of the servo motor is much greater than the Stribeck characteristic velocity, the output value of the Stribeck effect function approaches the Coulomb friction torque, reflecting the condition where dynamic friction dominates under fully lubricated conditions.

[0064] The bristle stiffness coefficient characterizes the equivalent elastic stiffness of the micro-protrusions on the contact surface, determining the response slope between frictional torque and angular displacement during the pre-sliding stage. Its value is related to the elastic modulus and surface morphology of the contact material. The bristle damping coefficient characterizes the equivalent internal damping of the micro-protrusions on the contact surface, used to describe the energy dissipation and phase lag characteristics during the friction dynamic process. The viscous friction coefficient characterizes the viscous damping component under hydrodynamic lubrication or boundary lubrication conditions, and is linearly proportional to the real-time angular velocity of the servo motor. The Coulomb friction torque is the constant frictional torque required to maintain uniform motion after relative sliding of the contact surfaces, and its value is related to the normal force of the contact surfaces and the dynamic friction coefficient. The maximum static friction torque is the maximum frictional torque that the contact surfaces can withstand before entering the sliding state from a static state, and its value is greater than the Coulomb friction torque.

[0065] The friction observer iteratively updates the equivalent deformation of the bristles and its rate of change using differential equations based on the real-time angular velocity of the servo motor, and calculates the comprehensive friction state under the current operating conditions by combining the Stribeck effect function. Subsequently, the friction observer linearly superimposes the product of the bristle stiffness coefficient and the equivalent deformation of the bristles, the product of the bristle damping coefficient and the rate of change of the equivalent deformation of the bristles, and the product of the viscous friction coefficient and the real-time angular velocity of the servo motor to obtain the friction torque compensation of the valve transmission mechanism.

[0066] The friction torque compensation is output to the speed loop controller, and algebraically superimposed with the initial torque control quantity generated by the speed loop controller to synthesize the target torque control quantity. The target torque control quantity is then adjusted by buffer deceleration and pulse width modulation to generate a motor drive signal, which is used to compensate for nonlinear frictional disturbances in the valve transmission mechanism, eliminate stick-slip motion, creeping phenomenon and positioning dead zone caused by friction, improve the stability and control accuracy of the valve during low-speed operation, start-up reversal and target position approach, and reduce the system's basic error and hysteresis.

[0067] like Figure 2 The diagram shown is a system block diagram of a servo valve control system provided in an embodiment of the present invention. The system includes: The ready module is used to receive the power-on trigger signal, perform system hardware self-test, and output the system ready status signal; The drive module is used to respond to the system ready state signal, control the system to enter the stroke learning mode, drive the servo motor to drive the valve to traverse the valve stroke range, and collect the real-time valve position through the absolute encoder to generate the valve stroke range and position-opening mapping relationship. The conversion module is used to receive external control commands and match the corresponding command parsing protocol, parse the external control commands based on the command parsing protocol to obtain the target valve opening, convert the target valve opening into the target valve position based on the position-opening mapping relationship, perform over-limit verification on the target valve position based on the valve stroke range, and output the target valve position control quantity. The output module is used to input the target valve position control quantity to a multi-level servo closed-loop control loop, perform closed-loop adjustment calculations in conjunction with the real-time valve position, output a motor drive signal to the servo driver, and synchronously output a valve position feedback signal.

[0068] Figure 2 The apparatus of the illustrated embodiment can be used to perform corresponding actions. Figure 1 The steps in the method embodiments shown are implemented in a similar manner and have similar technical effects, and will not be repeated here.

[0069] An electronic device includes a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor performs the steps of a servo valve control method as described in any of the above.

[0070] like Figure 3 The diagram shown is a hardware structure schematic of an electronic device according to an embodiment of the present invention. The electronic device 30 includes: a processor 31, a memory 32, and a computer program; wherein... The memory 32 is used to store the computer program, and the memory may also be flash memory. The computer program is, for example, an application program or functional module that implements the above method.

[0071] The processor 31 is configured to execute the computer program stored in the memory to implement the various steps performed by the device in the above method. For details, please refer to the relevant descriptions in the preceding method embodiments.

[0072] Alternatively, the memory 32 can be either standalone or integrated with the processor 31.

[0073] When the memory 32 is a device independent of the processor 31, the device may further include: Bus 33 is used to connect the memory 32 and the processor 31.

[0074] A readable storage medium storing a computer program, which, when executed by a processor, is used to implement the steps of a servo valve control method as described in any of the above claims.

[0075] The readable storage medium can be a computer storage medium or a communication medium. A communication medium includes any medium that facilitates the transfer of computer programs from one location to another. A computer storage medium can be any available medium accessible to a general-purpose or special-purpose computer. For example, a readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application-Specific Integrated Circuit (ASIC). Alternatively, the ASIC can be located in a user equipment. Of course, the processor and the readable storage medium can also exist as discrete components in a communication device. The readable storage medium can be a read-only memory (ROM), random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0076] The present invention also provides a program product including executable instructions stored in a readable storage medium. At least one processor of the device can read the executable instructions from the readable storage medium, and the at least one processor executes the executable instructions to cause the device to implement the methods provided in the various embodiments described above.

[0077] In the embodiments of the above-described device, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly manifested as execution by a hardware processor, or execution by a combination of hardware and software modules within the processor.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A servo valve control method, characterized in that, The method includes: Receives the power-on trigger signal and performs a system hardware self-test, and outputs a system ready status signal; In response to the system ready status signal, the control system enters the stroke learning mode, drives the servo motor to move the valve through the valve stroke range, and collects the real-time valve position through the absolute encoder to generate the valve stroke range and position-opening mapping relationship; Receive external control commands and match the corresponding command parsing protocol, parse the external control commands based on the command parsing protocol to obtain the target valve opening, convert the target valve opening into the target valve position based on the position-opening mapping relationship, perform over-limit verification on the target valve position based on the valve stroke range, and output the target valve position control quantity. The target valve position control quantity is input to a multi-level servo closed-loop control loop, and closed-loop adjustment calculation is performed in conjunction with the real-time valve position. The motor drive signal is output to the servo driver, and the valve position feedback signal is output synchronously.

2. The servo valve control method according to claim 1, characterized in that, The process of receiving the power-on trigger signal, performing system hardware self-test, and outputting a system ready status signal includes: The system detects the voltage amplitude and ripple coefficient of the power input, determines whether the voltage is within the rated voltage operating range, and outputs the power detection result signal. When the power detection result signal is qualified, the absolute encoder, the servo driver, the operation panel and the communication interface are sequentially tested for connectivity, and a hardware self-test status code is generated. Obtain the hardware self-test pass threshold, compare the hardware self-test status code with the hardware self-test pass threshold, if the hardware self-test status code is the same as the hardware self-test pass threshold, output the system ready status signal, and synchronously load and send the default configuration parameters stored in the non-volatile memory, including control mode, reference dead zone value and torque upper limit threshold.

3. The servo valve control method according to claim 1, characterized in that, In response to the system readiness signal, the control system enters the stroke learning mode, drives the servo motor to move the valve through the valve stroke range, and collects the real-time valve position through an absolute encoder to generate a valve stroke range and position-opening mapping relationship, including: In response to the system ready status signal, the system receives the stroke learning trigger command, controls the system to enter the stroke learning mode, drives the servo motor to drive the valve to the closing direction at a preset low speed, collects the motor torque through the servo driver, and simultaneously collects the real-time valve position through the absolute encoder. When the motor torque is detected to reach the calibrated torque threshold and the duration exceeds the calibrated duration, the current valve position value collected by the absolute encoder is locked and recorded as the end point of the closing stroke. The servo motor is driven to move the valve in the opening direction at the preset low speed. The motor torque is collected by the servo driver, and the real-time valve position is collected by the absolute encoder at the same time. When the motor torque is detected to reach the calibrated torque threshold and the duration exceeds the preset duration, the current valve position value collected by the absolute encoder is locked and recorded as the opening stroke endpoint; The valve stroke range is determined based on the closing stroke endpoint and the opening stroke endpoint, and a linear correspondence is established between the real-time valve position and valve opening degree collected by the absolute encoder, generating the position-opening degree mapping relationship.

4. The servo valve control method according to claim 3, characterized in that, The process involves receiving external control commands and matching them with corresponding command parsing protocols, parsing the external control commands based on the command parsing protocols to obtain the target valve opening, converting the target valve opening into a target valve position based on the position-opening mapping relationship, performing limit checks on the target valve position based on the valve stroke range, and outputting a target valve position control quantity, including: The signal type of the external control command is detected, and the command parsing protocol corresponding to CAN communication, analog quantity, switch quantity and fieldbus is matched to identify the valid data segment of the external control command. The valid data segment is parsed based on the instruction parsing protocol obtained by matching, and the parsed valid data segment is subjected to first-order low-pass filtering and range conversion to obtain the target valve opening. Based on the position-opening degree mapping relationship, the target valve opening degree is converted into the target valve position through linear interpolation. The valve target position is checked for exceeding limits based on the valve stroke range. If the valve target position value is within the valve stroke range, the valve target position value is output as the valve target position control quantity. If the valve target position value is less than the valve position endpoint value corresponding to the closing stroke endpoint of the valve stroke range, the valve target position value is clamped to the valve position endpoint value corresponding to the closing stroke endpoint and output as the valve target position control quantity. If the valve target position value is greater than the valve position endpoint value corresponding to the opening stroke endpoint of the valve stroke range, the valve target position value is clamped to the valve position endpoint value corresponding to the opening stroke endpoint and output as the valve target position control quantity.

5. The servo valve control method according to claim 1, characterized in that, The process of inputting the target valve position control quantity into a multi-level servo closed-loop control loop, performing closed-loop adjustment calculations in conjunction with the real-time valve position, outputting a motor drive signal to the servo driver, and synchronously outputting a valve position feedback signal includes: The target valve position control quantity is input to the multi-level servo closed-loop control loop, the position deviation between the target valve position control quantity and the real-time valve position is calculated, the position deviation is input to the position loop controller, and the target speed control quantity is output. Calculate the speed deviation between the target speed control quantity and the real-time speed feedback quantity of the servo motor; input the speed deviation quantity to the speed loop controller to generate the initial torque control quantity; superimpose the friction torque compensation quantity on the initial torque control quantity to output the target torque control quantity; When the position deviation is less than a preset buffer distance threshold, it is determined that the valve has entered the buffer zone. The ratio of the position deviation to the total length of the buffer distance is calculated to obtain the deceleration coefficient. Based on the deceleration coefficient, the target torque control quantity is scaled proportionally to generate a buffer torque control command. Based on the buffer torque control command, a PWM drive signal with a corresponding duty cycle is generated as the motor drive signal and output to the servo driver. The current valve position is acquired and converted into a feedback signal format that matches the external control command, and the valve position feedback signal is output synchronously.

6. The servo valve control method according to claim 5, characterized in that, The step of inputting the target valve position control quantity into the multi-level servo closed-loop control loop, calculating the position deviation between the target valve position control quantity and the real-time valve position, inputting the position deviation into the position loop controller, and outputting the target speed control quantity includes: The target valve position control quantity is input to the multi-level servo closed-loop control loop. The position deviation e(k) between the target valve position control quantity and the real-time valve position at the current time k is calculated. A non-singular fast terminal sliding surface s(k) is constructed, and the corresponding calculation formula is as follows: ； In the formula, q are the positive coefficients of the non-singular fast terminal sliding surface; p and q are the power parameters of the non-singular fast terminal sliding surface, and both are positive odd numbers, satisfying p>q>0; Using a hyperbolic tangent composite power-law approaching law, the sliding mode reaching law control components are calculated based on the non-singular fast terminal sliding mode surface s(k). The corresponding calculation formula is as follows: ； In the formula, is a positive coefficient of the hyperbolic tangent composite power reaching law; m and n are power parameters of the hyperbolic tangent composite power reaching law, both are positive odd numbers and satisfy m < n; T is the control period; tanh( ) is the hyperbolic tangent function; Based on the position deviation, the servo motor, valve transmission mechanism, and valve are equivalent to a second-order rigid body rotation structure, and an equivalent dynamic model of the valve is established. Based on the sliding mode invariance principle, the rate of change of the non-singular fast terminal sliding surface is set to 0, and substituted into the equivalent dynamic model of the valve to obtain the equivalent control components. The equivalent control components are superimposed with the sliding mode reaching law control components to obtain the position loop output increment. Obtain the position loop output at the previous time k-1, and add it to the position loop output increment at the current time k to obtain the position loop output at the current time k; The position loop output at the current time k is subjected to speed limiting processing, and the target speed control quantity is output.

7. A servo valve control method according to claim 5, characterized in that, The process of generating the frictional torque compensation includes: A friction observer is constructed based on the LuGre dynamic friction model to estimate the friction torque compensation amount of the valve transmission mechanism in real time. The corresponding calculation formula is as follows: ； ； ； In the formula, z is the equivalent deformation of the bristles of the valve transmission mechanism; The rate of change of the equivalent deformation of the bristles in the valve transmission mechanism; This refers to the real-time angular velocity of the servo motor. Stribeck characteristic velocity; These are the bristle stiffness coefficient, bristle damping coefficient, and viscous friction coefficient of the LuGre dynamic friction model, respectively. The Coulomb friction torque of the valve transmission mechanism; This represents the maximum static friction torque of the valve transmission mechanism. This is the Stribeck effect function.

8. A servo valve control system, characterized in that, The system, applied to a servo valve control method as described in any one of claims 1-7, comprises: The ready module is used to receive the power-on trigger signal, perform system hardware self-test, and output the system ready status signal; The drive module is used to respond to the system ready state signal, control the system to enter the stroke learning mode, drive the servo motor to drive the valve to traverse the valve stroke range, and collect the real-time valve position through the absolute encoder to generate the valve stroke range and position-opening mapping relationship. The conversion module is used to receive external control commands and match the corresponding command parsing protocol, parse the external control commands based on the command parsing protocol to obtain the target valve opening, convert the target valve opening into the target valve position based on the position-opening mapping relationship, perform over-limit verification on the target valve position based on the valve stroke range, and output the target valve position control quantity. The output module is used to input the target valve position control quantity to a multi-level servo closed-loop control loop, perform closed-loop adjustment calculations in conjunction with the real-time valve position, output a motor drive signal to the servo driver, and synchronously output a valve position feedback signal.

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor runs the computer program stored in the memory, the processor performs the steps of a servo valve control method as described in any one of claims 1-7.

10. A readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it is used to implement the steps of a servo valve control method as described in any one of claims 1-7.

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