A valve positioner control method and system to eliminate overshoot

Abstract

The application belongs to the technical field of intelligent valve positioner, and provides a valve positioner control method and system for eliminating overshoot phenomenon, which determines current remaining distance according to the difference between current valve position and set valve position; obtains predicted brake distance according to current control current, current valve movement speed and preset fitting curve model; compares the predicted brake distance with the current remaining distance, and when overshoot phenomenon occurs, determines new control current according to the current remaining distance and the fitting curve model, and controls the valve positioner through the new control current; dynamically adjusts the control current by comparing the actual remaining distance with the predicted brake distance, avoids the generation of overshoot and oscillation, avoids the occurrence of overshoot phenomenon under the premise of ensuring high control speed, improves the stability of the control process, effectively reduces the valve seat vibration and the impact of fluid on the valve interior, and prolongs the overall service life of the valve.

Description

Technical Field

[0001] This invention belongs to the field of intelligent valve positioner technology, and particularly relates to a valve positioner control method and system for eliminating overshoot. Background Technology

[0002] Intelligent valve positioners typically need to meet two requirements: the ability to quickly and accurately change the valve opening to meet the needs of the production process; and the smoothest possible valve movement to minimize vibration and extend valve life. The quality of the control algorithm used in the intelligent valve positioner has a fundamental impact on valve control.

[0003] Most existing intelligent valve positioners employ PID control algorithms or fuzzy PID control algorithms. Regardless of the algorithm used, it is difficult to achieve a balance between control speed and control stability. To improve response speed, a larger current is required, driving the valve at a faster speed, which reduces control stability. If the brake is not applied promptly when the valve opens, the actual valve position may exceed the set position, resulting in overshoot. The controller then needs to drive the valve back to the set position; this excess is called overshoot. Overshoot increases response time, and the extra movement increases mechanical wear and vibration, leading to poor sealing performance of the valve's packing. Furthermore, overshoot causes the valve to move in the opposite direction, resulting in significant impact from the fluid in the pipeline, causing valve seat deformation or damage and reducing the valve's service life. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a valve positioner control method and system that eliminates overshoot. This invention dynamically adjusts the control current by comparing the actual remaining distance with the predicted braking distance, thereby avoiding overshoot and oscillation. While ensuring a high control speed, it avoids overshoot, improves the stability of the control process, effectively reduces valve seat vibration and fluid impact on the valve's interior, and extends the overall service life of the valve.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, the present invention provides a valve positioner control method for eliminating overshoot, comprising: Obtain the current valve position, the set valve position, the current control current, and the current valve movement speed; The remaining distance is determined based on the difference between the current valve position and the set valve position; the predicted braking distance is obtained based on the current control current, the current valve movement speed, and a preset fitting curve model. By comparing the predicted braking distance with the current remaining distance, it is determined whether overshoot has occurred. If so, a new control current is determined based on the current remaining distance, the current remaining distance, and the fitted curve model, and the valve positioner is controlled by the new control current. Otherwise, the valve positioner is controlled according to the current control current.

[0006] Furthermore, the fitted curve model is a linear fitting model: ; ; Where D is the valve braking distance; V is the valve speed; and I is the braking current. , , and These are the coefficients obtained from the fitting process; and It is a bias term; This represents the forward motion model of the valve; This represents the valve's reverse motion model.

[0007] Furthermore, the fitted curve model is a nonlinear fitting model: ; ; Where D is the valve braking distance; V is the valve speed; and I is the braking current. , , , , , , and These are the coefficients obtained from the fitting process; This represents the forward motion model of the valve; This represents the valve's reverse motion model.

[0008] Furthermore, the current remaining distance is the absolute value of the difference between the current position of the valve and the set position of the valve.

[0009] Furthermore, if the current remaining distance is less than or equal to the predicted braking distance, it indicates that there is no overshoot and no intervention is made to the current control current; if the current remaining distance is greater than the predicted braking distance, it indicates that overshoot has occurred, and intervention is made to the current control current, switching the current control current to a new control current.

[0010] Furthermore, the current control current is gradually switched to the new control current through interpolation.

[0011] Secondly, the present invention also provides a valve positioner control system for eliminating overshoot, comprising: The data acquisition module is configured to: acquire the current valve position, the set valve position, the current control current, and the current valve movement speed; The distance determination module is configured to: determine the current remaining distance based on the difference between the current valve position and the valve set position; and obtain the predicted braking distance based on the current control current, the current valve movement speed, and a preset fitting curve model. The control module is configured to: determine whether overshoot occurs by comparing the predicted braking distance with the current remaining distance; if so, determine a new control current based on the current remaining distance and the fitted curve model, and control the valve positioner using the new control current; otherwise, control the valve positioner according to the current control current.

[0012] Thirdly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the valve positioner control method for eliminating overshoot as described in the first aspect.

[0013] Fourthly, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor executes the program to implement the steps of the valve positioner control method for eliminating overshoot as described in the first aspect.

[0014] Fifthly, the present invention also provides a computer program product, the computer program product comprising a computer program, which, when executed by a processor, implements the steps of the valve positioner control method for eliminating overshoot as described in the first aspect.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention first determines the current remaining distance based on the difference between the current valve position and the set valve position; then, it obtains the predicted braking distance based on the current control current, the current valve movement speed, and a preset fitting curve model; next, it compares the predicted braking distance with the current remaining distance to determine if overshoot has occurred; finally, if overshoot occurs, it determines a new control current based on the current remaining distance, the current remaining distance, and the fitting curve model, and controls the valve positioner using the new control current. By dynamically adjusting the control current by comparing the actual remaining distance with the predicted braking distance, overshoot and oscillation are avoided. This ensures a high control speed while preventing overshoot, improving the stability of the control process, effectively reducing valve seat vibration and fluid impact on the valve's interior, and extending the overall service life of the valve. Attached Figure Description

[0016] The accompanying drawings, which form part of this embodiment, are used to provide a further understanding of this embodiment. The illustrative embodiments and their descriptions are used to explain this embodiment and do not constitute an improper limitation of this embodiment.

[0017] Figure 1 The control flow of the intelligent valve positioner in Embodiment 1 of the present invention is as follows; Figure 2 The parameter self-tuning process of the intelligent locator in Embodiment 1 of the present invention is as follows; Figure 3 This refers to the valve oscillation waveform information of the intelligent positioner in Embodiment 1 of the present invention; Figure 4 The process for establishing the prediction model in Embodiment 1 of the present invention. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0020] Example 1: A smart valve positioner is a device that automatically controls the opening and closing of valves. Simply installing the smart valve positioner on the valve enables automatic valve control, making it widely used in industrial control. The smart valve positioner integrates microcontrollers and digital communication technology, featuring high sensitivity and high reliability. It improves the dynamic response characteristics of valves and enhances valve positioning accuracy. Smart valve positioners typically need to meet two requirements: the ability to quickly and accurately change the valve opening to meet the needs of the production process; and the smoothest possible valve movement to minimize vibration and extend valve life.

[0021] Intelligent valve positioners employ various control algorithms, each with different control parameters. Regardless of the algorithm used, the intelligent valve positioner must be able to determine the parameters within the control algorithm itself; this process is known as parameter self-tuning. Through parameter self-tuning, the intelligent valve positioner can automatically measure parameters such as valve friction, valve zero point, and valve stroke range, and calculate a set of control parameters based on the measured results. It is evident that the quality of the control algorithm used by the intelligent valve positioner has a fundamental impact on valve control. Even when using the same control algorithm, the control parameters obtained during self-tuning will differ, again significantly affecting the valve control process.

[0022] Most existing intelligent valve positioners employ PID control algorithms or fuzzy PID control algorithms, which are extensions of PID control. In reality, regardless of the control algorithm used, it's difficult to simultaneously achieve both control speed and control stability. Increasing response speed necessitates increasing the current to drive the valve at a faster speed, which reduces control stability. Just like driving a car, the faster the speed, the longer the braking distance; valve movement follows the same principle. If the host computer sends a control signal to the intelligent valve positioner, requesting the valve to open from 0% to 50%, and the valve's actual position reaches 60% due to delayed "braking," the controller needs to drive the valve back from 60% to the set position of 50%. The excess (60% - 50%) is called the system overshoot. Overshoot is detrimental to the system. On one hand, it increases response time; on the other hand, the extra movement increases mechanical wear and vibration. Valve vibration can lead to poor sealing performance of the packing at the valve seal. On the other hand, overshoot causes the valve to move in the opposite direction, which can cause the fluid in the pipeline to have a greater impact on the valve, potentially leading to deformation or damage to the valve seat and reducing the valve's service life.

[0023] To address at least one of the aforementioned problems, this embodiment provides a valve positioner control method that eliminates overshoot. While ensuring a high control speed, it avoids overshoot, improves the stability of the control process, effectively reduces valve seat vibration and fluid impact on the valve's interior, and extends the overall service life of the valve.

[0024] like Figure 1 As shown, the control flow of the intelligent valve positioner includes: the MCU control module receives the valve position signal given by the host computer and compares it with the current valve position signal. The drive current is determined by the preset control algorithm in the MCU control module, and the actuator drives the valve to move after receiving the drive current. The preset control algorithm can be a PID algorithm or a fuzzy algorithm, etc. The control method in this embodiment can be applied to algorithms such as PID or fuzzy algorithms to eliminate overshoot.

[0025] During the parameter self-tuning stage of the intelligent valve positioner, a specific self-tuning process is used to model the valve's overshoot phenomenon, enabling prediction of overshoot. Commonly used algorithms such as PID or fuzzy algorithms cannot predict overshoot in advance; they adjust after overshoot occurs. In this embodiment, however, the algorithm measures and models the overshoot at different valve speeds during the parameter self-tuning stage, providing advance prediction rather than post-overshoot correction. Based on the model's advance prediction and the valve's current speed, the drive current is adjusted to prevent overshoot.

[0026] This embodiment pre-predicts the required braking distance of the valve by using data obtained from the self-tuning or simulation of the valve positioner, combined with the valve's motion state (valve speed + valve control current). The control current is dynamically adjusted by comparing the actual remaining distance with the predicted braking distance, thereby avoiding overshoot and oscillation. The parameter self-tuning process of the intelligent positioner in this embodiment is as follows: Figure 2 As shown: S1. Measurement of the valve's maximum operating range: The processor outputs a 100% positive PWM current to drive the valve to open. It monitors the valve position in real time; if the valve position remains unchanged within a set time, it indicates that the valve is fully open, and this position is recorded as the maximum valve position, Pmax.

[0027] The processor sends a 100% PWM current in the opposite direction to drive the valve to close. It also monitors the valve position in real time. If the valve position stops changing within a set time, it indicates that the valve is completely closed, and this position is recorded as the minimum valve position value, Pmin.

[0028] To ensure accuracy, the measurement is repeated twice. If the results of the two measurements differ significantly, an error is reported and the program terminates. If the error between the two measurements is within the allowable range, the average value is taken as the final result.

[0029] S2, Actuator action time measurement: The measurement of motion time is achieved using methods such as timers, which will not be described in detail here.

[0030] S3, Actuator drive current measurement: The processor sends a PWM current to drive the valve to open to approximately 50% and then stops. The positive control current is then slowly increased, starting from 0% and gradually increasing to drive the valve open further. The processor monitors valve position changes in real time. If the valve movement exceeds a set value (e.g., from 55% to 56%), the PWM current at that moment is recorded as the positive reference current I+1.

[0031] The processor sends a PWM current to drive the valve to open to approximately 50% and then stops. The reverse control current is then slowly increased, starting from 0% and gradually increasing to drive the valve to close. The processor monitors valve position changes in real time. If the valve movement exceeds a set value (e.g., from 45% to 44% closing), the PWM current at that moment is recorded as the reverse reference current I-2.

[0032] To ensure measurement accuracy, the same test was performed at valve openings of 25%, 50%, and 75%. If the error of the reference current at different points was within the allowable range, the average value was taken as the final result. If there was a large error in the reference current at different locations, a second strategy was adopted. The reference current at each location was recorded, and the corresponding reference current was used near the corresponding location. For example, the current measured at 25% was used as the reference in the 0%-33% opening range. In the 33%-66% opening range, the current measured at 50% was automatically switched as the reference.

[0033] S4. Control Parameter Configuration and Calibration: The processor first drives the valve to the fully closed position, then sends a 100% positive PWM current to drive the valve to open as quickly as possible. Once the valve position exceeds 50%, it immediately switches to a 100% negative PWM current. Since the valve only begins to brake after reaching 50%, the final stopping position will definitely be greater than 50% (e.g., the valve eventually stops at 60%). At this point, driven by the 100% negative PWM current, the valve brakes in a square motion and then accelerates in the opposite direction, driving the valve to close again. This process continues until the valve position exceeds 50% again (this time from 60% towards the valve closing direction), at which point the current direction is switched again, driving the valve to move in the other direction, repeating this process. The valve will oscillate repeatedly around the 50% position. The specific movement is as follows... Figure 3 As shown.

[0034] Repeat the above operation at the 25% and 75% positions respectively. If the control parameter errors measured at the 25%, 50%, and 75% positions are within the allowable range, then a single set of control parameters is used to control the entire process. If the parameters at the three different positions differ too much, then a control strategy using different control parameters in different control intervals is adopted.

[0035] S5. Feedforward channel parameter measurement: like Figure 4As shown, the prediction model establishment process includes: Since the dynamic response of the valve at different stroke positions may not be the same, it is necessary to obtain the bidirectional dynamic response corresponding to multiple preset stroke positions (such as 20%, 40%, 60%, 80%). The bidirectional dynamic response includes the positive dynamic response and the negative dynamic response. In order to improve the accuracy of the model, the dynamic response is the average value after multiple measurements.

[0036] The forward and reverse dynamic responses at different travel positions are fitted separately to obtain dynamic response fitting curves. These dynamic response fitting curves are used to predict the overshoot of the positioner.

[0037] Optionally, the process of obtaining the dynamic response fitting curve is as follows: For each preset stroke position, different currents are used to drive the valve movement; typical currents can be 25%, 50%, 75%, and 100%. When the valve positioner drives the actuator to the preset stroke position, the driving current is immediately reversed, driving the valve to move in the opposite direction. After the valve position returns to the preset stroke position, the driving current is reversed again. This drives the valve to generate periodic oscillations at the preset stroke positions. The oscillation waveforms are analyzed and fitted at different positions and with different currents to obtain the dynamic response fitting curve.

[0038] In one embodiment, optionally, the valve speed is denoted by V; the faster the speed, the longer the braking distance. The control current is denoted by I; the larger the current, the greater the braking force and the shorter the braking distance. The braking distance is denoted by D, the distance required from the start of braking to a complete stop. Since the dynamic characteristics of the valve may differ at different positions, zone calibration is performed to improve control accuracy. Optionally, the valve position is divided into three zones: from 0% to 33%, from 33% to 66%, and from 66% to 100%, with 25%, 50%, and 75% positions selected as reference points for each zone. The calibration method is the same for each zone, only the reference points differ; therefore, only the calibration process from 33% to 66%, using the 50% position as the reference point, is described. The specific process is as follows: S201, Drive the valve at maximum speed V max Open the valve and monitor its position in real time. The valve position reaches the reference point P at 50%. ref Then, apply the maximum braking current to decelerate I. max Record the position P after the valve decelerates and stops. real The overshoot at this point is P+50_O 1.0×1.0 Recorded as: P+50_O 1.0×1.0 =|P real -P ref |; Maintain valve speed at 100% V maxThe braking speed remains unchanged, but is adjusted to 66% of I. max Repeat step S201. The overshoot at this point is P+50_O. 1.0×0.6 Recorded as: P+50_O 1.0×0.6 =|P real -P ref |; Multiple sets of motion speeds and braking currents were repeatedly tested, with a maximum speed of V. max The valve speed V is generally selected from three reference values, namely 100% of V. max 66% of V max 33% of V max The braking current I can be selected from three reference values, namely 100% of the maximum braking current I. max 66% of the maximum braking current I max 33% of the maximum braking current I max .

[0039] The total number of measurements required is the combination of the selected reference values ​​for speed and current. For example, if three reference values ​​are selected for each, there are 3 × 3 = 9 combinations. Therefore, the overshoot can be calculated for 9 different cases. Specific combinations are shown in Table 1. Table 1. Overshoot under different conditions

[0040] The above nine scenarios represent data measured during the valve opening process. Since the performance of a valve during opening and closing is usually not entirely the same, data also needs to be measured during the valve closing process.

[0041] After each valve opening, data from the valve closing process can be measured simultaneously and recorded as P-50. There are also 9 possible results (replace all "+" signs with "-"), as shown in Table 2: Table 2 Overshoot under different conditions during valve closing

[0042] Ultimately, each position can get 9. 2 = 18 sets of data. To improve control accuracy, the 0%-100% range was divided into three areas for measurement: 0% to 33%, 33% to 66%, and 66% to 100%. The three positions of 25%, 50%, and 75% were selected as reference points for the three areas respectively.

[0043] Therefore, a total of 18 can be obtained. 3 = 54 sets of data.

[0044] The collected data is similar to that shown in Table 3: Table 3 Braking distance under different valve speeds and braking currents

[0045] Based on experimental observations, the relationship between the valve braking distance D (to address the dimension issue in the fitting process, the result obtained during fitting calculations is a dimensionless value without units, as below) and the valve speed V (to address the dimension issue in the fitting process, a dimensionless percentage or only a dimensionless speed value is used during fitting calculations, as below) and the braking current I (to address the dimension issue in the fitting process, a dimensionless percentage or only a dimensionless current value is used during fitting calculations, as below) can be approximated as linear. Therefore, a linear regression model is used to establish the first type of fitting curve model: ; ; in, , , and These are the coefficients obtained through calculation and fitting; and It is a bias term; This represents the forward motion model of the valve (the braking distance during the valve opening process). This represents the valve's reverse motion model (the braking distance during the valve closing process).

[0046] Different models may be used for different valve types. When higher accuracy is required or sufficient self-tuning time is available, more accurate and complex models, such as nonlinear models, can be used. ; ; in, , , , , , , and These are coefficients obtained through calculation and fitting. This represents the forward motion model of the valve; This represents the valve's reverse motion model.

[0047] The sensor data is filtered when measuring the braking distance. In this embodiment, a moving average filter is used to accurately measure the final braking position of the valve, eliminating interference caused by sensor inaccuracies. Analysis shows that there should be a positive correlation between valve speed V and braking distance D, as well as between braking current and braking distance D. For example, when the valve speed V remains constant, a larger braking current should result in a shorter braking distance. This embodiment adds a correlation logic detection function; when a non-positive correlation is detected, the erroneous data is remeasured to eliminate outliers.

[0048] After modeling, the braking distance D can be obtained as a model function of the valve speed V and the braking current I, denoted as: D=F(V,I); When the user issues a valve movement command to the processor, the internal control algorithm drives the valve to move. During the valve movement, this embodiment monitors the current valve position P in real time. now and valve set position P set And detect the current control current I real and the current valve movement speed V real Substituting these values ​​into the model function D=F(V,I), the predicted braking distance D is calculated. pre .

[0049] Compare the predicted braking distance D pre and the current remaining distance D real =|P now -P set |, thus deriving the corresponding control strategy. If the current remaining distance D pre Less than or equal to the predicted braking distance D real This indicates that under the model's prediction, there will be no overshoot phenomenon, and in this case, the algorithm in this paper will not intervene in the original algorithm.

[0050] If the current remaining distance D pre Greater than the predicted braking distance D real This indicates that overshoot will occur under the model's prediction. In this case, intervention is needed in the control current of the original algorithm, based on the current actual distance D. real and actual speed V real Conversely, substituting these values ​​into the model D=F(V, I), we can obtain the new control current I. pre The original current control current I... real Switching to the new control current I predicted in this embodiment real That's all.

[0051] In actual control, abrupt changes during control current switching may cause slight vibrations in the mechanical structure. Therefore, in most cases, current changes will not have an observable impact. When the current change is large, interpolation can be used to make the current switching smoother, theoretically resulting in better stability. Specific measures are as follows: The current control current is I... real The new current calculated by the algorithm in this paper should be I. pre At this point, the current control current I is not directly applied. real Switch to new control current I pre Instead, several intermediate interpolations are added. The current control current is gradually switched to the new control current through interpolation. For example, if the current (in milliamperes) needs to be changed from 1.2mA to 0.3mA, it can be changed from 1.2mA to 0.9mA, then from 0.9mA to 0.6mA, and finally from 0.6mA to 0.3mA.

[0052] This embodiment effectively suppresses system overshoot and oscillation without affecting the original algorithm. It predicts the required braking distance of the valve by pre-calculating data obtained from the valve positioner's self-tuning or simulation, combined with the valve's motion state (valve speed + valve control current). The control current is dynamically adjusted by comparing the actual remaining distance with the predicted braking distance, thus avoiding overshoot and oscillation. Since the valve positioner's control algorithm itself requires self-tuning to determine control parameters, this embodiment only needs to add an additional tuning step to the original self-tuning mechanism, making it widely applicable.

[0053] In the above method, the calculation of parameters in the model is a one-time process. Once the parameters are calculated during the tuning phase, they remain fixed until the next tuning. Because the dynamic response characteristics of the equipment vary under different temperatures, loads, and operating stages, using a fixed set of model coefficients to uniformly fit all historical data can easily lead to model coefficients that only reflect the average characteristics of historical samples, making it difficult to accurately describe the current operating conditions. To further improve the adaptability and stability of the model, in another embodiment, the "fixed model parameters" are further improved to "adaptive model parameters." "Adaptive model parameters" refer to model parameters that dynamically adjust as the equipment operates, transforming the parameters into a dynamic function driven by "operating condition identification + historical error + control current." The establishment of the adaptive dynamic function relies on the past dynamic characteristics of the valve.

[0054] First, the valve's most recent N movements are recorded in memory. The information to be recorded includes: the magnitude of the control signal change, the valve's action time, and the valve's trajectory (i.e., a "position-time" graph of the valve's movement). When determining N, if the valve moves frequently, N can be set to a larger value, for example, N=20. If the valve does not move frequently, N can be set to a smaller value, for example, N=5. The N movements are selected as one calculation cycle for the dynamic function. The dynamic correction term for the k-th cycle is denoted as... The two new models are: ; ; as well as: ; ; Among them, D k+1 This represents the new model output, where... This indicates a newly added dynamic compensation item. The specific calculation method is as follows: First, read the data from the first N actions. The results are recorded, including the maximum value (Max) and the minimum value (Min). For the second model, the results are recorded from... The maximum and minimum values ​​are obtained. The algorithm calculates valve position control based on historically saved valve movement trajectories, dividing it into two segments: a "rapid action zone" and a "fine-tuning zone." First, the valve movement trajectory in the "rapid action zone" is analyzed. The valve position is then calculated using time difference. ; in, It is a fixed sampling period; The valve is in the first k The position at any given moment; The valve is in the first The position at that moment.

[0055] Within the "fast-action zone," the ideal valve movement trajectory is smooth, therefore the difference results... Each term should have the same sign (positive when the valve is open in the forward direction, negative when the valve is closed in the reverse direction). If the difference result... The change in the sign of the valve indicates that the deceleration process was too "aggressive." This manifests as a minimum point in the valve's "velocity-time" graph, disrupting the continuity of the valve's motion trajectory. To eliminate this effect, the valve's "braking speed" should be reduced.

[0056] The specific adjustment rule is as follows: when the sign of the result of the difference calculation is found to be in the first... arrive When a reversal occurs between sampling points, record the difference result at this point: ; as well as: ; The second difference is obtained by taking the absolute value of the difference between the two and treating it as an outlier. Right now: ; in, Here, N represents the N sets of valve action information recorded previously; M represents the number of outliers. For example, This indicates the first outlier in the second set of historical data. This indicates the third outlier in the second set of historical data.

[0057] Sum all the outlier data: ; The summation result P is used as one of the variables for dynamically adjusting parameters.

[0058] Calculations are performed based on historically preserved valve movement trajectories, and the overshoot of the control process is analyzed within the "fine-tuning zone" of valve movement. The overshoot of the first N valve movements is statistically analyzed and denoted as... Similarly, sum the data from the first N iterations: ; Next, we will consider the dynamic parameters P and Q together. To ensure that the contribution of each term is controllable, we will first perform normalization.

[0059] Dynamically correct parameters Defined as: ; in, and To influence the weights, empirical values ​​are selected. By adding dynamic correction parameters to analyze the valve's dynamic processes over the past N times, automatic parameter optimization is achieved. This further suppresses and eliminates overshoot and makes the valve's operation smoother. Simultaneously, the added "memory" of previous dynamic processes enhances the model's robustness.

[0060] Example 2: This embodiment provides a valve positioner control system that eliminates overshoot, including: The data acquisition module is configured to: acquire the current valve position, the set valve position, the current control current, and the current valve movement speed; The distance determination module is configured to: determine the current remaining distance based on the difference between the current valve position and the valve set position; and obtain the predicted braking distance based on the current control current, the current valve movement speed, and a preset fitting curve model. The control module is configured to: determine whether overshoot occurs by comparing the predicted braking distance with the current remaining distance; if so, determine a new control current based on the current remaining distance and the fitted curve model, and control the valve positioner using the new control current; otherwise, control the valve positioner according to the current control current.

[0061] The working method of the system is the same as the valve positioner control method for eliminating overshoot in Example 1, and will not be repeated here.

[0062] Example 3: This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the valve positioner control method for eliminating overshoot as described in Embodiment 1.

[0063] Example 4: This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and capable of running on the processor. When the processor executes the program, it implements the steps of the valve positioner control method for eliminating overshoot as described in Embodiment 1.

[0064] Example 5: This embodiment provides a computer program product, which includes a computer program. When the computer program is executed by a processor, it implements the steps of the valve positioner control method for eliminating overshoot as described in Embodiment 1.

[0065] The above description is merely a preferred embodiment of this practice and is not intended to limit the scope of this practice. Various modifications and variations can be made to this practice by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this practice should be included within the protection scope of this practice.

Claims

1. A valve positioner control method for eliminating overshoot, characterized in that, include: Obtain the current valve position, the set valve position, the current control current, and the current valve movement speed; The remaining distance is determined based on the difference between the current valve position and the set valve position; the predicted braking distance is obtained based on the current control current, the current valve movement speed, and a preset fitting curve model. By comparing the predicted braking distance with the current remaining distance, it can be determined whether overshoot has occurred; If so, a new control current is determined based on the current remaining distance and the fitted curve model, and the valve positioner is controlled by the new control current; otherwise, the valve positioner is controlled according to the current control current.

2. The valve positioner control method for eliminating overshoot as described in claim 1, characterized in that, The fitted curve model is a linear fitting model: ； ； Where D is the valve braking distance; V is the valve speed; and I is the braking current. , , and These are the coefficients obtained from the fitting process; and It is a bias term; This represents the forward motion model of the valve; This represents the valve's reverse motion model.

3. The valve positioner control method for eliminating overshoot as described in claim 1, characterized in that, The fitted curve model is a nonlinear fitting model. ； ； Where D is the valve braking distance; V is the valve speed; and I is the braking current. , , , , , , and These are the coefficients obtained from the fitting process; This represents the forward motion model of the valve; This represents the valve's reverse motion model.

4. The valve positioner control method for eliminating overshoot as described in claim 1, characterized in that, The current remaining distance is the absolute value of the difference between the current position of the valve and the set position of the valve.

5. A valve positioner control method for eliminating overshoot as described in claim 1, characterized in that, If the current remaining distance is less than or equal to the predicted braking distance, it indicates that there is no overshoot and no intervention is made to the current control current; if the current remaining distance is greater than the predicted braking distance, it indicates that overshoot has occurred, and intervention is made to the current control current, switching the current control current to a new control current.

6. The valve positioner control method for eliminating overshoot as described in claim 5, characterized in that, The current control current is gradually switched to the new control current by interpolation.

7. A valve positioner control system for eliminating overshoot, characterized in that, include: The data acquisition module is configured to: acquire the current valve position, the set valve position, the current control current, and the current valve movement speed; The distance determination module is configured to: determine the current remaining distance based on the difference between the current valve position and the valve set position; and obtain the predicted braking distance based on the current control current, the current valve movement speed, and a preset fitting curve model. The control module is configured to: determine whether overshoot has occurred by comparing the predicted braking distance with the current remaining distance; If so, a new control current is determined based on the current remaining distance and the fitted curve model, and the valve positioner is controlled by the new control current; otherwise, the valve positioner is controlled according to the current control current.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the valve positioner control method for eliminating overshoot as described in any one of claims 1-6.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that, When the processor executes the program, it implements the steps of the valve positioner control method for eliminating overshoot as described in any one of claims 1-6.

10. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the steps of the valve positioner control method for eliminating overshoot as described in any one of claims 1-6.

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