Gate control method and system based on intelligent valve positioner

Abstract

The invention discloses a gate control method and system based on an intelligent valve positioner, and relates to the technical field of gate dynamic control, and the method comprises the steps: setting parameters based on the intelligent valve positioner, dividing a valve into a plurality of intervals according to the parameters, and setting an independent PID parameter for each interval; the PID parameter is substituted into the optimized PID controller to generate a control signal; performing dead-zone compensation on the control signal, and generating a final control signal by combining the control signal; and valve control is conducted according to the final control signal. The two-way communication capability of the HART protocol is fully utilized, so that an operator can accurately adjust various parameters of the valve in a remote control room, and the parameters comprise key indexes such as flow characteristics, split-range control setting and stroke range. The remote control not only improves the convenience of operation, but also enables a control room to master the working state, operation parameters and alarm information of on-site electrical equipment at any time through a real-time data transmission function.

Description

Technical Field

[0001] The present invention relates to the technical field of gate dynamic control, and in particular to a gate control method and system based on an intelligent valve positioner. Background Art

[0002] With the continuous development of industrial automation technology, valves, as key components in fluid control systems, play a vital role in industrial production. Traditional valve control systems mostly use simple switch control or PID control based on fixed parameters. This control method is often difficult to accurately adjust the valve opening when facing complex working conditions, resulting in slow system response speed, insufficient control accuracy, and high energy consumption. In recent years, with the rapid development of intelligent technology, intelligent valve positioners have gradually become the new favorite in the field of industrial automation. Intelligent valve positioners can monitor the working status of valves in real time and adjust control parameters according to working conditions through built-in sensors and advanced control algorithms, thereby achieving more accurate valve control. However, existing intelligent valve positioners still face some challenges in practical applications, especially when dealing with complex nonlinear systems. Traditional PID control algorithms are difficult to adapt to changing working conditions, resulting in poor performance of the system in terms of dynamic response and stability.

[0003] In the prior art, the traditional PID controller uses fixed control parameters, which makes it difficult to cope with the nonlinear characteristics of the valve at different openings, which limits the control accuracy and response speed of the system. For example, in some working conditions that require precise adjustment, the valve opening changes are not linear, and the PID controller with fixed parameters may cause the system to overshoot, oscillate or respond lag. In addition, the existing valve control system usually lacks dead zone compensation for the control signal, which further reduces the control accuracy of the system, especially in the case of small valve opening adjustments. Although some improved technologies attempt to improve the robustness and accuracy of the system through methods such as adaptive control or fuzzy control, these methods are often highly complex and computationally intensive, and are difficult to be widely used in actual industrial environments. Therefore, how to design a more accurate control strategy for different valve opening ranges while ensuring system stability has become an important topic in the current development of intelligent valve positioner technology. Summary of the invention

[0004] In view of the problems existing in the existing control system, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is that the traditional PID controller uses fixed control parameters and is difficult to cope with the nonlinear characteristics of the valve at different openings, which limits the control accuracy and response speed of the system.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides a gate control method based on an intelligent valve positioner, which comprises:

[0008] Parameters are set based on the intelligent valve positioner, and the valve is divided into a plurality of intervals according to the parameters, and independent PID parameters are set for each interval;

[0009] Substituting the PID parameters into the optimized PID controller to generate a control signal;

[0010] Performing dead zone compensation on the control signal and combining the control signal to generate a final control signal;

[0011] The valve is controlled according to the final control signal.

[0012] As a preferred solution of the gate control method based on the intelligent valve positioner of the present invention, the optimization of the PID controller includes the following steps:

[0013] Add nonlinear compensation items to compensate for the inherent nonlinear characteristics of the valve;

[0014] Determine whether the valve actuator is saturated. If saturated, add anti-saturation items;

[0015] The anti-saturation term includes,

[0016] When the system is in normal working condition, The anti-windup term has no significant effect on control;

[0017] When the system reaches saturation, The anti-windup term will limit the integral action and prevent integral windup;

[0018] in, is the error change rate, is the preset maximum allowable error change rate.

[0019] As a preferred solution of the gate control method based on the intelligent valve positioner of the present invention, the nonlinear compensation term is as follows:

[0020] f(x)=a*x 2 +b*x+c

[0021] Among them, a, b, and c are parameters determined according to the valve characteristic curve;

[0022] The anti-saturation term is shown as follows:

[0023]

[0024] in, is the preset maximum allowable error change rate, is the error change rate, is the anti-saturation term.

[0025] As a preferred solution of the gate control method based on the intelligent valve positioner of the present invention, the control signal is generated based on the optimized PID controller, as shown in the following formula:

[0026]

[0027] Among them, u(t) is the controller output, e(t) is the error signal (the difference between the set value and the actual value), Kp is the proportional gain, Ki is the integral gain, Kd is the differential gain, Kf*f(x) is the nonlinear compensation term, is the anti-saturation term.

[0028] As a preferred solution of the gate control method based on the intelligent valve positioner of the present invention, wherein: in the multiple intervals, if the valve opening is at the boundary of the interval, a transition algorithm is used to make the output of the PID controller smoothly transition;

[0029] The transition algorithm is shown below:

[0030]

[0031] Among them, x n is the starting point of interval n, x (n+1) It is the starting point of interval n+1.

[0032] As a preferred solution of the valve control method based on the intelligent valve positioner of the present invention, wherein: performing dead zone compensation on the control signal includes:

[0033] Detecting the minimum effective control input, minimum position change and leakage flow of the valve according to the intelligent valve positioner;

[0034] Calculating a valve deadband estimate based on the minimum effective control input, the minimum position change, and the leakage flow;

[0035] Dynamic dead-band compensation is performed on the control signal according to the valve state.

[0036] As a preferred solution of the valve control method based on the intelligent valve positioner of the present invention, the calculation of the estimated value of the valve dead zone is shown in the following formula:

[0037] d est =k 1 *u min +k 2 *m+k 3 *q

[0038] Among them, k1, k2, k3 are weight coefficients, which need to be determined through experiments or experience;

[0039] The dead zone compensation is shown as follows:

[0040]

[0041] Where ucomp(t) is the basic PID control output after dead-band compensation:

[0042]

[0043] In a second aspect, an embodiment of the present invention provides a gate control system based on an intelligent valve positioner, which includes:

[0044] A PID parameter setting module, used to set parameters based on the intelligent valve positioner, and divide the valve into multiple intervals according to the parameters, and set independent PID parameters for each interval;

[0045] A control signal generating module, used for substituting the PID parameters into the optimized PID controller to generate a control signal;

[0046] The dead zone compensation module is used to perform dead zone compensation on the control signal and generate a final control signal in combination with the control signal.

[0047] In a third aspect, an embodiment of the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, wherein: when the processor executes the computer program, any step of the above-mentioned gate control method based on the intelligent valve positioner is implemented.

[0048] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, any step of the above-mentioned gate control method based on the intelligent valve positioner is implemented.

[0049] The beneficial effect of the present invention is to make full use of the two-way communication capability of the HART protocol, so that the operator can accurately adjust the various parameters of the valve in the remote control room, including key indicators such as flow characteristics, split-range control settings and travel range. This remote control not only improves the convenience of operation, but also enables the control room to grasp the working status, operating parameters and alarm information of the on-site electrical equipment at any time through the real-time data transmission function, so as to adjust the control strategy in time to ensure the stability and safety of the system. In view of the nonlinear characteristics of the valve, the present invention divides the entire stroke of the valve into multiple intervals and sets independent PID parameters for each interval. The selection of this interval parameter is based on the characteristics of each interval, so that in the low opening interval, a higher gain can be used to overcome static friction and improve the response speed, while in the high opening interval, the gain is reduced to avoid overreaction and reduce oscillation. In addition, the added nonlinear compensation term can effectively compensate for the inherent nonlinear characteristics of the valve, further improving the control accuracy and robustness of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0051] Figure 1 The flowchart of the gate control method based on the intelligent valve positioner is shown in FIG. DETAILED DESCRIPTION

[0052] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0053] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0054] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0055] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0056] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0057] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] Example 1

[0059] Reference Figure 1 , which is the first embodiment of the present invention, provides a gate control method based on an intelligent valve positioner, comprising:

[0060] The intelligent valve positioner based on HART protocol of the present invention has good practical application effect. In addition to the basic function of general positioners to change the input current signal into pneumatic pressure signal, the intelligent valve positioner based on HART protocol can also configure the positioner through the central control unit to change the flow characteristics of the regulating valve; use its communication capability to realize remote configuration of field instruments and provide rich diagnostic information for fault location.

[0061] Specifically, operators can use the two-way communication capability of the HART protocol in the remote control room to accurately adjust the various parameters of the gate. These parameters include but are not limited to key indicators such as flow characteristics, split-range control settings and travel range. At the same time, the HART protocol also supports real-time data transmission, allowing the control room to keep track of the working status, operating parameters and alarm information of on-site electrical equipment at any time.

[0062] Furthermore, the microcontroller and microprocessor based on the intelligent electrical valve positioner determine the direction of action of the actuator, and then automatically set the stroke and zero point of the actuator structure to ensure that the valve can respond accurately throughout the entire range of motion. Next, the leakage is automatically tested to evaluate the sealing performance of the valve, and finally the minimum positioning increment is determined to complete automatic parameter identification.

[0063] The entire valve stroke is divided into multiple intervals according to specific parameters, and a set of independent PID parameters is set for each interval. The selection of these parameters is based on the characteristics of each interval. For example, in the low opening interval, a higher gain is required to overcome static friction and improve response speed, while in the high opening interval, the gain needs to be reduced to avoid overreaction and reduce oscillation.

[0064] Preferably, the valve control system has obvious nonlinear characteristics, especially in the small opening and large opening ranges, but the traditional PID controller will be insufficient in processing such nonlinearity, resulting in reduced control accuracy or oscillation. Therefore, this embodiment adds a nonlinear compensation term to compensate for the inherent nonlinear characteristics of the valve, which can be expressed as a fixed polynomial as follows:

[0065] f(x)=a*x 2 +b*x+c

[0066] Among them, a, b, and c are parameters determined according to the valve characteristic curve.

[0067] More specifically, this nonlinear compensation is achieved through the following steps:

[0068] Perform valve characteristic tests to obtain flow or pressure difference data at different openings.

[0069] Using curve fitting techniques, the optimal values ​​of parameters a, b, and c are determined.

[0070] f(x) is calculated in real time in the control algorithm and added to the control output as a compensation.

[0071] Furthermore, through a period of valve control, it is found that the actuator saturation problem is often encountered when the actuator is saturated with a large adjustment or the external interference is large. When the actuator is saturated, the integral term will continue to accumulate, resulting in a large overshoot after the system returns to normal. To solve this problem, this embodiment adds an anti-saturation term, as shown in the following formula:

[0072]

[0073] in, is the preset maximum allowable error change rate, is the error change rate, is the anti-saturation term;

[0074] When the system is in normal working condition, The anti-windup term has no significant effect on control.

[0075] When the system reaches saturation, The anti-windup term limits the integral action and prevents integral windup.

[0076] The integration into the traditional PID controller formula is shown below:

[0077]

[0078] Among them, u(t) is the controller output, e(t) is the error signal (the difference between the set value and the actual value), Kp is the proportional gain, Ki is the integral gain, Kd is the differential gain, Kf*f(x) is the nonlinear compensation term, is the anti-saturation term.

[0079] Because different PID parameters are used for each interval, in order to avoid sudden changes in control output at the interval boundary, an interpolation algorithm is used at the interval transition point to ensure a smooth transition of the control output. Assuming that the current valve opening is x%, it is between interval n and interval n+1, and the PID parameters are calculated using the following formula:

[0080]

[0081] Among them, x n is the starting point of interval n, x (n+1) It is the starting point of interval n+1.

[0082] Furthermore, when the control signal changes, the valve dead zone will cause the valve to not change accordingly, making it impossible to perform more precise control. First, we analyze the factors that cause the valve dead zone, which are mainly as follows:

[0083] Static Friction: The initial friction that needs to be overcome when the valve is actuated.

[0084] Mechanical Clearance: The small gap between the valve stem and the actuator.

[0085] Deformation of sealing elements: such as deformation of O-rings under pressure.

[0086] Fluid Force: The force exerted by the fluid on the valve, resisting valve movement.

[0087] Furthermore, the valve dead zone is estimated in real time by using d_est=f(u_min,m,q), where u_min is the minimum effective control input, m is the minimum positioning increment, and q is the leakage amount.

[0088] First, the control signal is gradually increased from zero. When the valve movement is detected for the first time, the current control signal value is recorded as the minimum effective control input.

[0089] Use the intelligent valve positioner to perform a small step test and record the minimum valve position change that can be reliably detected as m;

[0090] When the valve is fully closed, the leakage flow is q;

[0091] The specific formula for calculating the valve dead zone is as follows:

[0092] d est =k 1 *u min +k 2 *m+k 3 *q

[0093] Among them, k1, k2, k3 are weight coefficients, which need to be determined through experiments or experience.

[0094] After the dead zone estimation is calculated, the dead zone compensation is performed. Specifically, it is shown in the following formula:

[0095] u comp (t)=u(t)+sign(u(t))*d est

[0096] Among them, u(t) is the original control signal and u_comp(t) is the compensated control signal.

[0097] The specific principles are:

[0098] When the control signal is positive, positive dead-time compensation is added

[0099] When the control signal is negative, negative dead zone compensation is added

[0100] This ensures that the control signal is always large enough to overcome the deadband;

[0101] Preferably, the dead zone compensation is dynamically adjusted according to the working state of the valve, and the amplitude and frequency characteristics of the control signal are first analyzed;

[0102] When it is detected that the control signal amplitude |u(t)| is less than the first preset threshold, the dead zone compensation d_est_adjusted = d_est*(1+α) is increased. When the control signal amplitude |u(t)| is greater than the second preset threshold, the original dead zone estimation is maintained. When the control signal frequency is high, the dead zone compensation is reduced: d est_adjusted =d_est*(1-β), when the control signal frequency is low, the original dead zone estimation is used.

[0103] The output of PID and the output of dead zone compensation are combined to obtain the final controller output, as shown in the following formula:

[0104]

[0105] Among them, u comp (t) is the basic PID control output after dead-zone compensation:

[0106]

[0107] The final u comp The (t) signal is transmitted to the intelligent valve positioner, which first analyzes and processes the received signal, and then compares the current position of the valve with the target position required by the control signal u_final(t) to calculate the position error. Based on the calculated position error, the intelligent positioner generates a corresponding execution signal to control the actuator to close or open the valve.

[0108] Furthermore, this embodiment also provides a gate control system based on an intelligent valve positioner, comprising:

[0109] Determine the PWM parameter module, which is used to dynamically adjust the frequency and duty cycle of PWM according to the current state of the gate control system;

[0110] An optimal PWM sequence determination module is used to construct a mathematical model of the gate control system, input the frequency and duty cycle of the PWM into the mathematical model, and determine the optimal PWM drive signal sequence using a model predictive control algorithm;

[0111] The gate control module is used to control the inflation and deflation of the valve according to the optimal PWM drive signal.

[0112] This embodiment also provides a computer device, which is applicable to the gate control method based on the intelligent valve positioner, including a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions to implement the gate control method based on the intelligent valve positioner proposed in the above embodiment.

[0113] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0114] This embodiment further provides a storage medium on which a computer program is stored. When the program is executed by a processor, the gate control method based on the intelligent valve positioner as proposed in the above embodiment is implemented.

[0115] The storage medium proposed in this embodiment and the data storage method proposed in the above embodiment belong to the same inventive concept. The technical details not fully described in this embodiment can be found in the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0116] Example 2

[0117] This is the second embodiment of the present invention. This embodiment provides a gate control method based on an intelligent valve positioner. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0118] In order to verify the performance advantages of the intelligent valve positioner of the present invention in industrial control systems, an experiment of an intelligent valve positioner based on the HART protocol was conducted. The valve control system involved in the experiment includes a pneumatic actuator, an intelligent valve positioner (supporting the HART protocol), a central control unit, and a remote control room connected thereto. The object of the experiment is a typical fluid control system, in which the parameters of valve control include flow, valve opening, response time, and sealing performance.

[0119] The experiment first connected the intelligent valve positioner to the central control unit through the HART protocol, ensuring that the remote control room can monitor and adjust the various parameters of the valve in real time. At the beginning of the experiment, the operator configured the initial flow characteristics of the valve through the HART protocol in the remote control room, and divided the valve stroke into a low opening range (0% to 30%), a medium opening range (30% to 70%), and a high opening range (70% to 100%), and set independent PID parameters for each range. Specifically, a higher gain parameter is set in the low opening range to overcome static friction and increase the response speed; the gain is reduced in the high opening range to avoid overreaction and reduce oscillation.

[0120] Subsequently, the experiment automatically completed the direction setting of the actuator, stroke zero point calibration, leakage test and sealing performance evaluation through the microprocessor and microcontroller of the intelligent valve positioner. During the entire experiment, real-time data was transmitted to the central control unit via the HART protocol, and the control room was able to grasp the operating status and response of the valve at any time.

[0121] In view of the nonlinear characteristics of the valve, the experiment further introduced a nonlinear compensation term. The compensation parameters a, b, and c were obtained by fitting the valve characteristic curve, and the compensation value f(x) was calculated in real time in the control algorithm and added to the control output as the compensation amount. In order to solve the control overshoot problem caused by actuator saturation, the experiment also introduced an anti-saturation term, and dynamically adjusted the dead zone compensation amount according to the actual working state of the valve during the control process to ensure the smooth transition of the control signal and the stability of the system. Finally, the control signal u_final(t) after nonlinear compensation and anti-saturation processing is transmitted to the intelligent valve positioner. After the positioner analyzes and processes the signal, it controls the actual opening of the valve. The specific comparison with the traditional PID is shown in the following table:

[0122] Table 1 Experimental data table

[0123]

[0124] It can be seen from the experimental data that the control performance of the intelligent valve positioner of the present invention in different opening ranges is significantly better than that of the traditional PID control system, especially in the low and high opening ranges. Specifically, the flow characteristics of the present invention in the low opening range reached 85%, the response time was shortened to 120ms, the leakage was reduced to 0.02L / min, and the sealing performance was improved to 98.5%. In contrast, the flow characteristics of the traditional PID control in the low opening range were only 75%, the response time was longer, 150ms, and the leakage was relatively large, reaching 0.05L / min, and the sealing performance was only 97.0%.

[0125] In the medium opening range, the intelligent valve positioner of the present invention also performs well, with a flow characteristic of 90%, a response time of 110ms, a leakage further reduced to 0.01L / min, and a sealing performance improved to 99.0%. In contrast, the flow characteristic of the traditional PID control in the medium opening range is 80%, the response time is 140ms, the leakage is 0.03L / min, and the sealing performance is 97.5%. In the high opening range, the flow characteristic of the present invention reaches 95%, the response time is 130ms, the leakage is maintained at 0.01L / min, and the sealing performance is further improved to 99.2%, while the corresponding data of the traditional PID control are 85%, 160ms, 0.02L / min and 98.0%.

[0126] In addition, by comparing the data of the opening error and the oscillation amplitude, the opening error and oscillation amplitude of the control system of the present invention in all intervals are significantly lower than those of the traditional PID control system. For example, in the low opening interval, the opening error of the present invention is 1.2% and the oscillation amplitude is 0.8%, while the opening error of the traditional PID control is 3.5% and the oscillation amplitude is 1.5%. Similarly, in the high opening interval, the opening error of the present invention is only 0.5% and the oscillation amplitude is 0.2%, while the traditional PID control is 1.5% and 0.7% respectively.

[0127] These data show that the present invention significantly improves the response speed, control accuracy and stability of the valve control system by introducing independent PID parameter interval settings, nonlinear compensation and anti-saturation processing, overcomes the shortcomings of traditional PID control in processing nonlinear characteristics, and shows obvious advantages in small and large opening intervals. By optimizing the control algorithm and reasonably configuring parameters, the intelligent valve positioner of the present invention achieves more accurate valve control, significantly improves the overall performance of the system, and fully demonstrates its innovation and superiority in the field of industrial automation control.

[0128] The experiment performed a series of control signal changes, recorded the valve response time, steady-state error, and control signal overshoot, and compared it with the traditional PID control method. The data is recorded in the table below.

[0129] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A gate control method based on an intelligent valve positioner, characterized in that: include, Parameters are set based on the intelligent valve positioner, and the valve is divided into a plurality of intervals according to the parameters, and independent PID parameters are set for each interval; Substituting the PID parameters into the optimized PID controller to generate a control signal; Performing dead zone compensation on the control signal and combining the control signal to generate a final control signal; The valve is controlled according to the final control signal.

2. The gate control method based on the intelligent valve positioner according to claim 1, characterized in that: The optimization of the PID controller comprises the following steps: Add nonlinear compensation items to compensate for the inherent nonlinear characteristics of the valve; Determine whether the valve actuator is saturated. If saturated, add anti-saturation items; The anti-saturation term includes, When the system is in normal working condition, The anti-windup term has no significant effect on control; When the system reaches saturation, The anti-windup term will limit the integral action and prevent integral windup; in, is the error change rate, is the preset maximum allowable error change rate.

3. The gate control method based on the intelligent valve positioner according to claim 2, characterized in that: The nonlinear compensation term is shown as follows: f(x)=a*x 2 +b*x+c Among them, a, b, and c are parameters determined according to the valve characteristic curve; The anti-saturation term is shown as follows: in, is the preset maximum allowable error change rate, is the error change rate, is the anti-saturation term.

4. The gate control method based on the intelligent valve positioner according to claim 3, characterized in that: The control signal is generated based on the optimized PID controller, as shown in the following formula: Among them, u(t) is the controller output, e(t) is the error signal (the difference between the set value and the actual value), Kp is the proportional gain, Ki is the integral gain, Kd is the differential gain, Kf*f(x) is the nonlinear compensation term, is the anti-saturation term.

5. The gate control method based on the intelligent valve positioner according to claim 4, characterized in that: In the plurality of intervals, if the valve opening is at the boundary of the interval, a transition algorithm is used to make the output of the PID controller transition smoothly; The transition algorithm is shown below: Among them, x n is the starting point of interval n, x (n+1) is the starting point of interval n+1.

6. The gate control method based on the intelligent valve positioner according to claim 5, characterized in that: Performing dead zone compensation on the control signal includes: Detecting the minimum effective control input, minimum position change and leakage flow of the valve according to the intelligent valve positioner; Calculate a valve deadband estimate value based on the minimum effective control input, the minimum position change, and the leakage flow; Dynamic dead zone compensation is performed on the control signal according to the valve state.

7. The gate control method based on the intelligent valve positioner according to claim 6, characterized in that: The calculation of the estimated valve deadband is as follows: d est =k1*u min +k2*m+k3*q Among them, k1, k2, k3 are weight coefficients, which need to be determined through experiments or experience; The dead zone compensation is shown as follows: Among them, u comp (t) is the basic PID control output after dead-zone compensation:

8. A gate control system based on an intelligent valve positioner, based on the gate control method based on an intelligent valve positioner according to any one of claims 1 to 7, characterized in that: include, A PID parameter setting module, used to set parameters based on the intelligent valve positioner, and divide the valve into multiple intervals according to the parameters, and set independent PID parameters for each interval; A control signal generating module, used for substituting the PID parameters into the optimized PID controller to generate a control signal; The dead zone compensation module is used to perform dead zone compensation on the control signal and generate a final control signal in combination with the control signal.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the gate control method based on the intelligent valve positioner according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the gate control method based on an intelligent valve positioner according to any one of claims 1 to 7 are implemented.

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