Angular travel intelligent electric actuator control system and electric actuator

Abstract

The invention relates to the technical field of electric actuators, in particular to an angular travel intelligent electric actuator control system and an electric actuator, and the angular travel intelligent electric actuator control system comprises a signal access module, a driving control module, a cooperative control module, a control verification module and a diagnosis output module; a control instruction of an electric actuator is obtained, the operation speed of each torque execution state serves as a target, a torque speed curve of multiple torque execution states is obtained, the standard operation duration of the switching process of each control instruction is determined, the control time of each instruction is extracted from each control instruction, and the actual control situation of each pipeline is obtained; calculating constant-speed execution time and variable-speed execution time of the electric actuators by using actual control conditions of the pipelines, judging control association of the electric actuators, and setting an association control coefficient; the correlation control coefficient is monitored, and when the correlation control coefficient exceeds a preset threshold value, an alarm is given; stability and accuracy in the control command switching process are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric actuators, in particular to an angular travel intelligent electric actuator control system and an electric actuator. Background Art

[0002] In the field of industrial automation, angular-turn intelligent electric actuators are widely used in scenarios such as valve control and fluid regulation. However, traditional control systems have shortcomings in the following aspects: traditional systems often find it difficult to accurately control the angular position and operating speed of the actuator; the coordinated actions between multiple actuators are not smooth enough, which can easily lead to system instability or inefficiency; traditional control systems usually do not have real-time monitoring and automatic diagnosis functions, and cannot detect and handle abnormal situations in a timely manner; due to the lack of accurate mapping relationships, the actuator response may be inaccurate.

[0003] For example, Chinese patent publication number CN112923115A discloses an electric actuator and its positioning control method, valve control system, and storage medium. The electric actuator of the present invention controls the operation of the motor driving the valve by controlling the frequency converter. The electric actuator obtains the current valve position value of the valve in real-time feedback, calculates the difference between the current valve position value and the target positioning point, and controls the motor to slowly decelerate until the motor speed reaches the preset low speed when the difference decreases to the first distance; and controls the motor to quickly decelerate to stop when the difference decreases to the second distance. The prior art describes the angle value that needs to be considered in the deceleration stage and the acceleration stage, and adjusts the angle according to this angle value, but this method easily ignores the actual operation of the electric actuator and cannot respond quickly according to working conditions or other conditions, resulting in limited overall processing effect.

[0004] For example, Chinese patent publication number CN117847305A discloses a mining valve control and protection system based on an embedded computer. The present invention first comprehensively considers the operating space, operating environment and suitability of operating conditions of each target loop valve, realizes accurate judgment on whether the control instructions of each target loop valve can be executed, and avoids safety accidents that may be caused by blind execution of loop valve control instructions. Secondly, during the execution of the control instructions of each operable valve, the valve control safety factor of the coal mine underground water pump unit is analyzed to realize centralized safety management of each operable valve of the coal mine underground water pump unit. After the corresponding control instructions of each operable valve are executed, the control performance evaluation coefficient of each operable valve is comprehensively analyzed and feedback is provided. The prior art describes that the temperature, working area and other parameters of each valve are controlled according to the threshold value of the parameters relative to the valve. However, this control method does not take into account the actual working speed of the electric actuator, resulting in only the average detector angle or the maximum response time during the overall control. The actual execution situation at each point of the electric actuator is not described, which makes it difficult to issue a warning later. It cannot explain the parts of the electric actuator that need dynamic adjustment and routine processing according to the relative time ratio of the electric actuator's operation, making it difficult to ensure stability and accuracy during the control command switching process. Summary of the invention

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: an angular stroke intelligent electric actuator control system, including: a signal access module, used to obtain the control instructions of the electric actuator, and determine the target angle, input current, output torque and operating speed corresponding to the control instructions.

[0006] The drive control module is used to take the operating speed of each torque execution state as the target, obtain the torque speed curve of multiple torque execution states by comparing the speed curves under each torque execution state, and introduce the input current corresponding to each operating speed to verify the switching process of each control command.

[0007] The collaborative control module is used to determine the standard operating time of the switching process of each control command, and extract the control time of each command from each control command according to the standard operating time of the switching work. The control time of each command is used to obtain the distance between each electric actuator when the control command is switched, and the actual control status of each pipeline is obtained.

[0008] The control verification module is used to use the actual control conditions of each pipeline to calculate the uniform speed execution time and variable speed execution time of the electric actuator, determine the control association of each electric actuator, and set the associated control coefficient.

[0009] The diagnosis output module is used to implement monitoring of the associated control coefficient. When the associated control coefficient exceeds a preset threshold, an alarm is issued and the diagnosis result is output according to the device associated with the associated control coefficient.

[0010] An electric actuator comprises: a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, the content of the system described in any one of the above items is realized.

[0011] The beneficial effects of the present invention are as follows: 1. The present invention establishes a mapping table of input current and angle to ensure that each control instruction can be accurately converted into a target angle, and then compares the speed curves under each torque execution state to obtain a torque-speed curve, so that the electric actuator can achieve smooth operation under different load conditions. The input current is also connected to verify the switching process of the control command to determine the stability and accuracy of the switching process.

[0012] 2. The present invention determines the standard operating time of each control command and extracts the control time of each command to ensure the coordinated actions of multiple actuators. Then, the operating status of the control command and other contents are drawn to form a control flow chart. In the control flow chart, each command is regarded as a control node. The relative situation of the electric actuator under these control commands is identified, and the connection relationship between the control nodes is described. Multiple subjects are also selected to set the cause of the error to ensure the overall coordination of the system, the stability of the switching between the control commands, and the traceability and multi-traceability of each control command when problems exist.

[0013] 3. The present invention calculates the uniform speed execution time and variable speed execution time of the electric actuator based on the actual control situation of each pipeline, and combines and describes the corresponding distribution of each device in the upstream and downstream, so that each electric actuator can maintain relative consistency in space and time, and thereby determines the relationship between each electric actuator, thereby determining the time allocation ratio required for the electric actuator, and the corresponding set distance, so as to determine that when there is a command transmission delay when setting the electric actuator on each pipeline, each device node can ensure that the system is processed in a certain coordination. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0015] Figure 1 It is a system framework diagram of an angular stroke intelligent electric actuator control system.

[0016] Figure 2 The invention is a flow chart of a drive control module of an angular stroke intelligent electric actuator control system.

[0017] Figure 3 The invention is a flow chart of a cooperative control module of an angular stroke intelligent electric actuator control system.

[0018] Figure 4The invention is a flow chart of a control verification module of an angular stroke intelligent electric actuator control system. DETAILED DESCRIPTION

[0019] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. If no specific techniques or conditions are specified in the embodiments, the techniques or conditions described in the literature in the art or the product specifications are used.

[0020] A control system for an angular stroke intelligent electric actuator comprises: a signal access module, a drive control module, a collaborative control module, a control verification module and a diagnostic output module; wherein the output end of the signal access module is connected to the drive control module, the output end of the drive control module is connected to the collaborative control module, the output end of the collaborative control module is connected to the control verification module, and the output end of the control verification module is connected to the diagnostic output module.

[0021] The signal access module is used to obtain the control instructions of the electric actuator and determine the target angle, input current, output torque and operating speed corresponding to the control instructions.

[0022] The drive control module is used to take the operating speed of each torque execution state as the target, obtain the torque speed curve of multiple torque execution states by comparing the speed curves under each torque execution state, and introduce the input current corresponding to each operating speed to verify the switching process of each control command.

[0023] The collaborative control module is used to determine the standard operating time of the switching process of each control command, and extract the control time of each command from each control command according to the standard operating time of the switching work. The control time of each command is used to obtain the distance between each electric actuator when the control command is switched, and the actual control status of each pipeline is obtained.

[0024] The control verification module is used to use the actual control conditions of each pipeline to calculate the uniform speed execution time and variable speed execution time of the electric actuator, determine the control association of each electric actuator, and set the associated control coefficient.

[0025] The diagnosis output module is used to implement monitoring of the associated control coefficient. When the associated control coefficient exceeds a preset threshold, an alarm is issued and the diagnosis result is output according to the device associated with the associated control coefficient.

[0026] like Figure 1 As shown, the current figure shows the corresponding technical means used by the system, and uses various technical means to calculate the current torque and related content to determine whether the data and control commands processed by the current electric actuator are implemented according to the preset requirements.

[0027] Among them, the information access module converts the external input analog signal (usually a 4-20mA current signal) into the angular position instruction of the actuator. After determining the form of the received electrical signal and the required target angle at this time, the relevant command is sent to the drive control module. The drive control module uses the PID controller to generate a suitable PWM signal to drive the motor to make the electric actuator reach the target position; then the collaborative control module uses TSN time synchronization to keep the time of multiple electric actuators consistent, and the control verification module calculates the associated control coefficient (K coefficient) to evaluate the coordination and stability between each device node, and adjusts the control parameters accordingly. Finally, when an abnormal situation is detected, the diagnostic output module sends an alarm message through the OPC UA protocol and provides detailed diagnostic results.

[0028] In one embodiment of the present invention, the angular stroke intelligent electric actuator is generally started by receiving a standard value current signal of 0-10, 4-20 mA or 1-5 volts, 4mA represents that the valve is fully closed, and 20mA represents that the valve is fully open; then the torque and displacement thrust of the device are adjusted according to the received current and time to adjust the output force of the current machine, thereby completing the description of torque and relative displacement.

[0029] If the electric actuator is controlled by a control signal, the corresponding position of its angular stroke can be aligned with the target angle, but the time used under the control command is different from the expected situation, so that the current pipeline opening is adjusted too fast or too slow, resulting in negative situations such as overpressure and overload in the pipeline under scheduling control. At this time, the processing of time is to determine whether the speed of the electric actuator changes at a constant speed or variable speed in accordance with the preset form under different control instructions, so that the connected pipeline can achieve a relatively stable operating state; to prevent the electric actuator from changing too fast, and the torque and displacement thrust generated by it are inconsistent with the requirements of the current control command, so as to achieve automatic adjustment and stability of the electric actuator.

[0030] At this time, it is necessary to judge whether the control process of the current electric actuator is stable and whether it can meet the needs of normal equipment processing based on the torque and relative displacement generated by the current electric actuator.

[0031] Therefore, the implementation method of the signal access module also includes: establishing a mapping table of input current and angle, determining the mapping relationship between the electric actuator and the input current when executing each target angle, and checking whether the current control instruction corresponds to the mapping table of input current and angle. If so, execute the current control instruction, otherwise re-acquire the control instruction.

[0032] For example, when a 12mA signal is input, the ADC chip is used to convert it into a digital value: 12mA→2457 (12-bit resolution); the corresponding angle is obtained by looking up the table: 4mA(0°), 20mA(90°)→θ_target=(12-4) / (20-4)×90°=45°; the instruction package is generated: {CMD: ANGLE_SET, Value: 45°, TimeStamp: 2023-09-011 4:00:00.123}; according to this generated control instruction, the target angle that the current electric actuator needs to adjust is known.

[0033] In one embodiment of the present invention, it is necessary to determine the current angle value of each electric actuator when executing a control command, and the angle value represents the degree of pipeline opening and the corresponding output torque controlled by the current electric actuator. Then, a torque-speed curve used under different medium flow rates is pre-stored to determine the working conditions of the electric actuator under each torsional execution state, as well as the process differences corresponding to the time required for the corresponding input current and the current mutation value when the control command is switched. The time at this time is checked to adjust each electric actuator in the relevant situation of controlling the pipeline, whether the control command represented by the current requires corresponding dynamic compensation to prevent differences in the switching angles of the electric actuators at different flow rates.

[0034] A series of torque-speed curves are preset according to different media flow rates. These curves define the best operating parameters, such as torque and speed, that the electric actuator should adopt under specific working conditions, such as different media flow rates. This helps ensure that the actuator can operate in the most optimized way and avoid overload or inefficiency.

[0035] When the control command switches, the input current will change, which will affect the working state of the actuator. By monitoring these current mutations and their corresponding time delays, the speed and accuracy of the actuator's response to new commands can be evaluated. If the response time is found to be too long or the current mutation is abnormal, it may mean that the control logic needs to be adjusted. At the same time, it is also necessary to determine the time required for the electric actuator to complete the control command after the command is executed. This time will indicate the corresponding time to complete the control command and the changes in parameters such as torque within the corresponding time, to prevent problems such as overpressure in some pipelines caused by rapid adjustments.

[0036] Each torque execution state refers to the torque output characteristics of the electric actuator under different working conditions, such as different medium flow rates, load conditions or valve openings. These states reflect the torque size and its changing rules required by the actuator to complete a specific task, and are important indicators for evaluating the performance and adaptability of the actuator.

[0037] like Figure 2As shown, the implementation method of the drive control module includes: respectively determining a speed curve for decelerating from the maximum operating speed of the electric actuator to a stop in each torque execution state, and a speed curve for reversely decelerating from a stop to a normal operating speed at the operating speed of the electric actuator in each torque execution state.

[0038] The speed curve from the maximum operating speed to the stop is realized to prevent the impact and vibration during the working process of the electric actuator. For example, rapid deceleration may cause mechanical shock and vibration, which may cause damage to equipment such as valves or baffles and their connected parts. Identifying how the electric actuator decelerates under different working conditions can understand the current working state of the electric actuator, and further prevent the negative impact of excessive deceleration of some electric actuators on the overall connecting pipeline. This curve mainly checks the speed curve represented when reaching or about to reach the target position, avoiding overshoot or under-adjustment caused by inertia, so as to extend the working life of the electric actuator as much as possible.

[0039] The purpose of the speed curve from a stopped state to an operating speed is to describe the normal operating speed of the electric actuator from a stopped state to the current target angle. For example, when starting from a stationary state, a larger initial torque is required to overcome static friction and other static resistances. The speed curve describing this situation can help us understand the working conditions of the motor and prevent excessive speed, which may cause motor overload or increase in current, and thus lead to problems with the control method of the electric actuator. At the same time, under working conditions such as different media, the speed curve represented by the electric actuator should also be adjusted to the corresponding situation as much as possible to adapt to more working conditions.

[0040] Taking the torque execution states corresponding to the speed curve as the starting point and the time for each electric actuator to complete the control command as the end point, each speed curve is intersected and combined with the output torque of the electric actuator to form a torque speed curve. The horizontal axis of the torque speed curve represents the operating speed of the electric actuator, which is degrees / second or revolutions / minute to indicate the speed of the electric actuator's angular rotation; the vertical axis of the torque speed curve represents the output torque of the electric actuator. The obtained torque speed curve is more inclined to the changes that occur after the electric actuator receives different control commands, to identify whether the torque and operating speed output by these changes tend to be normal.

[0041] It is determined whether the torque-speed curve is a complete speed curve. If so, the time interval corresponding to the torque-speed curve is determined. Otherwise, the speed curve is re-intersected.

[0042] It is determined whether the time interval corresponding to the torque-speed curve corresponds to the control instruction. If so, the torque-speed curve is output.

[0043] After obtaining the torque-speed curve, the event interval of the torque-speed curve needs to be adjusted. The implementation method of outputting the torque-speed curve also includes: determining the time interval of the torque-speed curve in each torque execution state, comparing the torque-speed curve with the input current according to each time interval, and determining the deviation value between the current angle and the target angle. The deviation value indicates the deviation value between the angle rotated per second and the angle that should be rotated per second under the control command within the time to reach the target angle; extracting the time period corresponding to each deviation value as the switching process of each control command output. At this time, the switching process of verifying each control command is to verify the multiple time periods corresponding to the deviation between the angle executed by the electric actuator and the target angle after executing the control command, so as to determine the deviation that the electric actuator can produce under different working conditions. The switching process represents the process implemented by the electric actuator after the control command is issued.

[0044] The implementation method of introducing the input current corresponding to each operating speed to verify the switching process of each control command includes: obtaining the starting point and end point of the time interval corresponding to each torque execution state, starting calculation from the starting point of the time interval, and comparing the slope value and the slope average value of each torque-speed curve after the input current is input.

[0045] Determine the time point when the slope value and the slope average value of each torque-speed curve reach the maximum value, and record the position of the time point in the time interval corresponding to each torque execution state, and obtain the state point of each torque execution state. The state point represents a data point represented by its timestamp, input current, working conditions, angle of the electric actuator, output torque and running speed at the corresponding time. The data point represents a point where the torque-speed curve can reach the maximum value under the relative slope. This point represents the position where the output torque and running speed can reach the allowable maximum value under different working conditions. This position will represent the operating limit of the electric actuator under a specific limit.

[0046] Using the data corresponding to each state point, the probability distribution of each state point in the corresponding time interval of each torque execution state is calculated. What is calculated at this time is the possibility of describing the state point under the corresponding data, which can be calculated by statistical methods. For example, the state point obtained at this time represents low torque and low speed, then the probability of this described state point at all the state points can be obtained by statistics. If the state point represents medium torque and medium speed, it can also be obtained in the same way. Then, the conditional probability of this probability under a certain torque execution state, that is, working conditions, is described as the probability distribution at this time.

[0047] At the same time, the probability can also be in the form of Gaussian distribution. The Gaussian probability of discrete distribution is calculated based on the corresponding values ​​of output torque and running speed. Then, the two probabilities are combined together in the form used by conditional probability to describe the probability distribution of each state point at this time.

[0048] Based on the probability distribution of each state point, the matching of the output torque and the operating speed when each state point is the optimal operating point is calculated. Finally, according to the matching of the output torque and the operating speed, the switching process of each output control command is selected.

[0049] When calculating the matching of output torque and operating speed when each state point is the optimal operating point, the content executed by the state point is calculated without obvious oscillation when each state point is in dynamic response, that is, the value fluctuation at this point is small. At this time, the content running at this state point will be marked as the optimal operating point.

[0050] The error value between the output torque and the running speed is calculated and output as the matching situation of the output torque and the running speed. That is, the error value between the output torque and the running speed and the corresponding data in the historical data is used as the content of the matching situation at this time.

[0051] When the error value between the output torque and the operating speed is greater than the preset error threshold, the corresponding time period is output as the switching process of each control command. At this time, it mainly describes that when each state point can reach the optimal state, if the error value is large at this time, then there may be a delay in executing the control command at this time, or the electric actuator may suffer an angle rotation loss due to slow dynamic response, so that the final angle cannot match the target angle, thereby affecting the pipeline adjustment process and increasing the risk of damage to some structures of the electric actuator.

[0052] For electric actuators, the torque is proportional to the angle, for example ;in, Indicates the output torque of the electric actuator, Indicates the angle of the electric actuator, Indicates the output shaft diameter (fixed value), Indicates the elastic modulus of the material (fixed value) , shaft length (fixed value), from which we can know the corresponding output torque of the current electric actuator under the set torque-speed curve, and then describe the working conditions of the electric actuator in different scenarios according to this output torque.

[0053] In one embodiment of the present invention, the time error of the switching process of each control command is mainly described in the collaborative control module to determine the action delay required by the electric actuator, that is, the product of the medium flow rate in the pipeline and the time delay, to determine the output of each control command under collaborative control.

[0054] The standard operating time refers to the average time required for the electric actuator to complete a control command switch under ideal conditions. This time is usually determined by the following factors: the maximum operating speed of the electric actuator; the range of opening variation of the valve or damper; and the response delay of the control system. At this time, the standard operating time in the time period of the switching process extracted by each control command will be obtained. This time can be used as the standard operating time used here by selecting the average time to execute the control command by simulating the scenario of the control command. Then, the time length value corresponding to the control command in the time period corresponding to the switching process is extracted, and then the two values ​​are compared to determine the cause of the problem of each control command relative to the normal situation, and a control flow chart is formed to describe the working process of the electric actuator under the control command; if the duration of some control commands deviates significantly from the average value, it is necessary to further analyze the cause, such as load changes or mechanical failures, etc. These situations will be marked in the control flow chart to describe the specific execution status of the current electric actuator.

[0055] The distance between two consecutive control commands refers to the actual running distance of the electric actuator, expressed as an angle or linear displacement, to express the difference in the angles required by the two adjacent control commands.

[0056] like Figure 3 As shown, the implementation method of the collaborative control module also includes: aligning the standard operating time of the switching process of each control command with the control time of each command to determine the switching time corresponding to each control command. The switching time described here represents the time required for the control command to execute the command switching process, that is, aligning the standard operating time with the control time of each command to determine whether there is a deviation in the time of the switching process, and then treating each control command as a node to connect multiple control commands.

[0057] The switching time, distance between all control commands and the operating status of the electric actuator are summarized to form a complete control flow chart, which is output as the actual control status of each pipeline. The operating status includes but is not limited to the following aspects: normal operation, overload protection, fault alarm, position deviation, response delay and oscillation, as shown in Table 1.

[0058] Normal operation: indicates that the actuator executes the command as expected without any exception.

[0059] Overload protection: When the actuator detects that the load exceeds its design, it automatically stops or slows down to protect itself from damage.

[0060] Fault alarm: refers to the actuator encountering mechanical or electrical problems during operation, resulting in the inability to complete the scheduled task.

[0061] Position deviation: There is a difference between the actual position reached and the target position.

[0062] Response delay: The time interval from receiving a command to starting an action exceeds the set value.

[0063] Oscillation phenomenon: An unstable state occurs when approaching the target position, which is manifested as repeated adjustments and inability to stabilize at the target position.

[0064] Table 1. Control command diagram

[0065]

[0066] Table 1 shows that there may be problems after two adjacent control commands. The commands 1-5 described here are not directly continuous control commands, but are only used to illustrate the possible content of the operating status that appears, and the current electric actuator uses a corresponding device with a range of 0-90° to describe what problems may occur on the electric actuator according to different needs.

[0067] The implementation method of forming a complete control flow chart also includes: treating each control command in the control flow chart as a control node, determining the connection relationship between each control node under the corresponding operating state, and then associating the current operating state with the situation of the control node executing the corresponding control command.

[0068] Use the connection relationship of each control node in the corresponding operating state to mark the direction of the relationship between each control node, and set connection constraints on the control flow graph according to the relationship direction, and traverse the control flow graph to match the direction; at this time, the relationship direction will indicate the direction of the instruction or data flow between the control commands, and each control node can be triggered in different operating states; when multiple control commands require the same working conditions, these commands should be reasonably grouped or linked in the control flow graph to ensure logical coherence and efficiency; at this time, the connection constraints ensure that the control commands not only need to meet specific working conditions to be executed, but also must follow the established operation sequence to prevent system abnormalities due to improper combinations. Direction matching involves verifying and confirming whether the actual connection between control nodes meets the expected design specifications based on the set relationship direction and connection constraints, ensuring that all paths are executed in the correct order and conditions.

[0069] Locate multiple subjects for direction matching, select the error causes corresponding to each subject, and summarize the error causes in the control flow chart. After the direction matching is completed, summarize the error causes corresponding to the main subjects in the control flow chart to make the data display more comprehensive.

[0070] As shown in Table 2, possible causes of errors and other contents when implementing the control command are explained.

[0071] Table 2. Summary of control commands

[0072]

[0073] As shown in Table 2, after connecting the cause of the error with the control flow chart, we can know the relevant situation if there is a problem with the current electric actuator. These data will be used as the corresponding conditions of the pipeline connected to the electric actuator in the subsequent identification, and the time matching and spatial consistency will be associated with the control to determine the corresponding condition of the electric actuator under the associated control.

[0074] In one embodiment of the present invention, when performing associated control, the electric actuators are divided into upstream devices and downstream devices in turn according to their positions, and then the uniform speed execution time and variable speed execution time during operation are compared to determine the time ratio of the upstream device and the downstream device, as well as the corresponding density, to judge the relationship between the electric actuators under associated control.

[0075] The uniform speed execution time indicates the time it takes for the electric actuator to move from one position to another at a constant speed. The position described at this time indicates the corresponding angle of the electric actuator. This mode is suitable for application scenarios that require smooth and predictable motion.

[0076] The variable speed execution time involves acceleration and deceleration stages, that is, the electric actuator does not always run at the same speed, but accelerates or decelerates according to demand; this is usually used in the following situations: fast response to demand, energy-saving optimization and complex control strategy scenarios, which require the electric actuator to complete the adjustment of the electric actuator angle in a fast response mode to complete the opening and closing of the valve.

[0077] Rapid response needs: If the system detects an emergency situation (such as overpressure or leakage), it may be necessary to quickly close or open the valve. At this time, the electric actuator will first accelerate to reach the maximum speed, and then decelerate when approaching the target position to avoid overshoot or damage to the equipment.

[0078] Energy-saving optimization: By intelligently controlling acceleration and deceleration, energy consumption can be reduced without affecting performance. For example, slowly increasing speed at the beginning of startup can reduce the motor starting current, thereby reducing the power load.

[0079] Complex control strategies: In some advanced control systems, the speed of the actuator may be dynamically adjusted according to the real-time working conditions to achieve the best process control effect. For example, based on the model predictive control (MPC) algorithm, the system can predict the future change trend based on the current state and adjust the actuator speed curve accordingly.

[0080] The uniform speed execution time and variable speed execution time identified here are calculated in a scenario involving multiple electric actuators. These devices choose different ways to adjust themselves, and the relative consistency of the electric actuators in space and time is judged based on these adjustment methods.

[0081] like Figure 4 As shown, the implementation method of the control verification module includes: based on the actual control situation of each pipeline, recording the parameters of the control instructions of the electric actuator from the previous position to the next position, and establishing a mapping relationship between each electric actuator; the parameters described at this time include the control instructions used, and the situation where the angle on the electric actuator changes from one angle to another, and then these data are associated to facilitate subsequent analysis of the correlation between each electric actuator in the upstream equipment and the downstream equipment.

[0082] The equipment interval of each electric actuator is calibrated, and the equipment interval includes the upstream equipment interval and the downstream equipment interval; the time ratio of the uniform speed execution time and the variable speed execution time corresponding to each equipment node in the equipment interval and the calibration distance of each equipment node are determined in turn. The calibration distance represents the physical distance of the electric actuators corresponding to each equipment node, that is, the relative distance in space. This distance is used to evaluate the situation when each electric actuator executes the command and rotates to the target angle considering the fluid transmission delay in the pipeline at the actual physical distance, so as to verify whether there is a corresponding error in the time ratio occupied by the selected working model under its signal transmission, so as to describe the correlation of each electric actuator under joint work.

[0083] Compare the time ratios between the device nodes, set the time ratio coefficients of the device nodes, and output the time ratio coefficients in sequence according to the distances between the device nodes in the upstream device interval and the downstream device interval and the upstream and downstream center points.

[0084] When outputting the time proportion coefficient in sequence, its implementation method also includes: taking the key node of logic control in the upstream equipment interval and the downstream equipment interval as the upstream and downstream center point, which node represents the main coordination point in the upstream and downstream equipment intervals, such as the key point of flow control, which is mainly used to quantify the distribution of each electric actuator in the pipeline layout position, so as to facilitate the subsequent verification of whether the allocated time ratio is normal.

[0085] According to the distance between each device node and the upstream and downstream center points, the time ratio of the uniform speed execution time and the variable speed execution time of each device node is compared in turn. The time step of each device node during adjustment is determined according to the value of the time ratio. The time ratio coefficient corresponding to each time step is traversed to determine the time ratio coefficient when the time ratio deviation is minimum.

[0086] Assume that there is a simple piping system consisting of three electric actuators A, B, and C. They are located in the upstream and downstream equipment intervals, respectively, and their distances to the upstream and downstream center points and their respective uniform speed and variable speed execution times are known as shown in Table 3.

[0087] Table 3. Device node diagram

[0088]

[0089] Table 3 shows the relative positions of the device nodes at this time, as well as the corresponding uniform speed execution time and variable speed execution time. Then, the center point at this time is found. For example, the upstream center point is valve V1, and the downstream center point is valve V2.

[0090] After calculating its position, verify the time scale difference. The time scale of device A is 0.667, the time scale of device B is 0.533, and the time scale of device C is 0.8. According to the time scale, the time steps of devices A, B, and C can be set to 0.1, 0.05, and 0.15 respectively (these are only example values, and they need to be adjusted according to the specific situation in actual applications). Then, the optimization algorithm is used to adjust the time scale coefficient to minimize the time scale deviation. For example, for device A, the initial time scale coefficient is 0.667. After multiple iterative adjustments, the final time scale coefficient may be 0.65 (assuming that this is the result of minimizing the deviation). Finally, check whether the time scale coefficients of all device nodes are reasonable, and ensure that the time scale allocation of the overall system meets the requirements. Finally, the time scale coefficient output by each device node can be obtained.

[0091] The optimization algorithm used is to define a loss function that measures the difference between the current time scale factor and the ideal time scale factor. For example, the mean square error (MSE) can be used as the loss function.

[0092] An initial value of the time scale factor is initialized for each device node. For each device node, the partial derivative of the loss function, i.e., the gradient, is calculated according to the current time scale factor, which indicates how changes in the gradient direction will affect the total loss.

[0093] Update the value of each time scale coefficient according to the gradient information, use the learning rate to update the time scale coefficient each time, and then repeat it continuously until the change of the loss function can be minimized, and output the time scale coefficient corresponding to this time to get the time scale coefficient that needs to be adjusted at present; the corresponding time step will also indicate the relative value of its learning rate. The above description case is only for illustrative purposes and is not the corresponding parameter in actual use.

[0094] The time proportion coefficient and the calibration distance are used to set the weight of each device node and calculate the associated control coefficient.

[0095] According to the time scale coefficient and the calibrated distance, the time weight and space weight of the device node are set respectively. The ratio of the time scale coefficient to the sum of the total time scale coefficients is used as the time weight of the device node. The reciprocal of the calibrated distance between each device node represents the space weight. The weighted sum of the time weight and the space weight is used as the subsequent association control coefficient. At this time, a weighted value of 0.6 is set for the time weight, and a weighted value of 0.4 is set for the space weight. The weighted values ​​of each device node are averaged to obtain the association control coefficient including all device nodes.

[0096] The diagnostic output unit is used to monitor the associated control coefficient. When the associated control coefficient exceeds a preset threshold, an alarm is issued and a diagnostic result is output according to the device associated with the associated control coefficient.

[0097] When the associated control coefficients are associated and the diagnostic output is output, the implementation method of the diagnostic output unit also includes: counting the number of associated devices when the associated control coefficient exceeds a preset threshold, and alarming each electric actuator in turn according to the position of each device.

[0098] When the associated control coefficient exceeds the preset threshold, the main purpose of the alarm is to solve the following problems and prevent potential risks.

[0099] Coordination issues between devices: If the associated control coefficient is abnormal, it may indicate that the actions of some devices are not coordinated, such as the failure of downstream devices to respond in time after the upstream device is adjusted. This may cause system instability or reduced efficiency. At this time, the alarm prompts the operation and maintenance personnel to check the communication link, signal delay or control logic between devices.

[0100] System performance degradation: Abnormal associated control coefficients may mean that the overall performance of the system is affected, such as inaccurate flow regulation, excessive pressure fluctuations, etc. Alarms are used to remind operators to optimize control strategies, adjust the time scale coefficient of the equipment, or recalibrate the equipment range.

[0101] Potential failure risk: Sudden changes in the associated control coefficients may be early signs of equipment failure, such as valve sticking, actuator motor overload, etc. Early detection of potential problems through alarms allows for maintenance or replacement of equipment to avoid larger system failures.

[0102] The present invention further provides an electric actuator, comprising: a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, the content of the system as described in any one of the above items is realized.

[0103] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention and they are still covered by the protection scope of the present invention.

Claims

1. A angular stroke intelligent electric actuator control system, characterized in that: include: The signal access module is used to obtain the control instructions of the electric actuator and determine the target angle, input current, output torque and running speed corresponding to the control instructions; A drive control module is used to take the running speed of each torque execution state as the target, obtain the torque speed curve of multiple torque execution states by comparing the speed curves of each torque execution state, and introduce the input current corresponding to each running speed to verify the switching process of each control command; The collaborative control module is used to determine the standard operating time of the switching process of each control command, and extract the control time of each command from each control command according to the standard operating time of the switching work, and use the control time of each command to obtain the distance between each electric actuator when the control command is switched, so as to obtain the actual control status of each pipeline; The control verification module is used to calculate the uniform speed execution time and variable speed execution time of the electric actuator using the actual control conditions of each pipeline, and to determine the control association of each electric actuator and set the associated control coefficient; The diagnosis output module is used to implement monitoring of the associated control coefficient. When the associated control coefficient exceeds a preset threshold, an alarm is issued and the diagnosis result is output according to the device associated with the associated control coefficient.

2. The angular stroke intelligent electric actuator control system according to claim 1, characterized in that: The implementation of the signal access module also includes: Establish a mapping table of input current and angle, determine the mapping relationship between the electric actuator and the input current when executing each target angle, and check whether the current control instruction corresponds to the mapping table of input current and angle. If so, execute the current control instruction, otherwise re-acquire the control instruction.

3. The angular stroke intelligent electric actuator control system according to claim 1, characterized in that: The implementation methods of the drive control module include: Determine respectively a speed curve of decelerating from the maximum running speed of the electric actuator to a stop in each torque execution state, and a speed curve of reversely decelerating from a stop to a normal running speed in each torque execution state at the running speed of the electric actuator; Taking each torque execution state corresponding to the speed curve as the starting point and the time when each electric actuator completes the control instruction as the end point, each speed curve is intersected and combined with the output torque of the electric actuator to form a torque speed curve; Determine whether the torque-speed curve is a complete speed curve. If so, determine the time interval corresponding to the torque-speed curve. Otherwise, re-intersect the speed curve. It is determined whether the time interval corresponding to the torque-speed curve corresponds to the control instruction. If so, the torque-speed curve is output.

4. The angular stroke intelligent electric actuator control system according to claim 3, characterized in that: The implementation method of outputting the torque speed curve also includes: Determine the time interval of the torque-speed curve under each torque execution state, compare the torque-speed curve with the input current according to each time interval, determine the deviation between the current angle and the target angle, extract the time period corresponding to each deviation value as the switching process of each control command output.

5. The angular stroke intelligent electric actuator control system according to claim 1, characterized in that: The implementation method of introducing the input current corresponding to each operating speed to verify the switching process of each control command includes: Get the starting point and end point of the time interval corresponding to each torque execution state, start calculating from the starting point of the time interval, and compare the slope value and the average slope value of each torque speed curve after the input current is input; Determine the time point at which the slope value and the slope average value of each torque-speed curve reach the maximum value, and record the position of the time point in the time interval corresponding to each torque execution state to obtain the state point of each torque execution state; Using the corresponding data of each state point, the probability distribution of each state point in the corresponding time interval of each torque execution state is calculated; Based on the probability distribution of each state point, the matching of the output torque and the operating speed when each state point is the optimal operating point is calculated. Finally, according to the matching of the output torque and the operating speed, the switching process of each output control command is selected.

6. The angular stroke intelligent electric actuator control system according to claim 1, characterized in that: The implementation of the collaborative control module also includes: Align the standard running time of the switching process of each control command with the control time of each command to determine the switching time corresponding to each control command; The switching time, distance between each other and the operating status of the electric actuator of all control commands are summarized to form a complete control flow chart, and the control flow chart is output as the actual control status of each pipeline.

7. The angular stroke intelligent electric actuator control system according to claim 6, characterized in that: The implementation methods for forming a complete control flow graph also include: Treat each control command in the control flow chart as a control node, and determine the connection relationship between each control node in the corresponding operating state; Use the connection relationship of each control node in the corresponding running state to mark the relationship direction between each control node, and perform connection constraints on the control flow graph according to the relationship direction, and traverse the control flow graph to perform direction matching; Locate multiple subjects with matching directions, select the error causes corresponding to each subject, and summarize the error causes in the control flow chart.

8. The angular stroke intelligent electric actuator control system according to claim 1, characterized in that: The implementation of the control verification module includes: Based on the actual control situation of each pipeline, record the parameters of the control instructions of the electric actuator from the previous position to the next position, and establish the mapping relationship of each electric actuator; Calibrate the equipment interval of each electric actuator, the equipment interval includes the upstream equipment interval and the downstream equipment interval; determine the time ratio of the uniform speed execution time and the variable speed execution time corresponding to each equipment node in the equipment interval, and the calibration distance of each equipment node; Compare the time ratios between the device nodes, set the time ratio coefficients of the device nodes, and output the time ratio coefficients in sequence according to the distances between the device nodes in the upstream device interval and the downstream device interval and the upstream and downstream center points; The time proportion coefficient and the calibration distance are used to set the weight of each device node and calculate the associated control coefficient.

9. The angular stroke intelligent electric actuator control system according to claim 8, characterized in that: The implementation method of outputting the time proportional coefficient in sequence also includes: Take the key nodes of logic control in the upstream equipment section and the downstream equipment section as the upstream and downstream center points; According to the distance between each device node and the upstream and downstream center points, the time ratio of the uniform speed execution time and the variable speed execution time of each device node is compared in turn. The time step of each device node during adjustment is determined according to the value of the time ratio. The time ratio coefficient corresponding to each time step is traversed to determine the time ratio coefficient when the time ratio deviation is minimum.

10. An electric actuator, characterized in that: include: A processor and a memory, wherein the memory stores a computer program, wherein when the computer program is executed by the processor, the content of the system according to any one of claims 1 to 9 is implemented.

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