Anti-pollution control algorithm for servo valve

Abstract

The invention relates to an anti-pollution control algorithm for a servo valve, which comprises the following steps of: establishing a real-time control model of a servo system according to response characteristics of the servo valve and an actuating device, acquiring an estimated value of the working state of the servo system at the current moment according to the real-time control model and an observed value of the working state of the servo system at the current moment, the control mode of the servo system is determined according to the cleaning requirement and the control state of the servo system, the control mode comprises a cleaning mode and a performance mode, and a control input signal of the servo valve is determined according to the estimated value and the control mode of the servo system at the current moment. According to the method, mathematical models of the servo valve and the actuating device are used, real-time prediction and calculation are conducted through the controller, on the premise that it is guaranteed that the actual response of the actuating device meets the control expectation, automatic cleaning of the servo valve in the normal operation process is achieved, the self-flushing capacity of the servo valve is improved, and the service life of the servo valve is prolonged. And faults such as valve element clamping stagnation caused by pollution of the servo valve are effectively prevented.

Description

Technical Field

[0001] The invention belongs to the technical field of servo system control, and in particular relates to a servo valve anti-pollution control algorithm. Background Art

[0002] Servo valves include electro-hydraulic servo valves and direct-drive servo valves, which are important components of servo systems. Figure 2 As shown. The servo valve receives the electrical signal from the controller, adjusts the position of its valve core, outputs hydraulic oil, fuel and other working media of different flow rates, and then changes the working state of actuators, valves and other actuators. Since the servo valve has the advantages of small size, high efficiency and large power amplification, it is widely used in aviation, mining, metallurgy and other fields. In engineering, due to the small size and precise structure of the servo valve, impurities caused by the pollution and coking of the working medium enter the servo valve through the pipeline, which will affect the normal action of the valve core, which will reduce the control quality of the servo valve at the least, and cause valve core jamming and other faults in severe cases, resulting in failure of servo system control and endangering the safe operation of the equipment.

[0003] Engineering experience and related research have shown that the periodic reciprocating motion of the valve core can flush and clean the servo valve, slow down the accumulation of impurities in the working medium in the servo valve, and enhance the servo valve's ability to resist pollution. In actual work, the servo valve is in a steady state most of the time, and the position of the valve core is relatively fixed. If the valve core is forced to move, it will inevitably have an adverse effect on the control of the actuator, and in severe cases, it will cause control fluctuations and affect work efficiency. Therefore, existing practices are mainly based on decoupling the cleaning of the servo valve core and normal control. Specific methods include off-site maintenance, shutdown maintenance, hardware redundancy, etc.

[0004] The off-site maintenance valve refers to the servo valve being removed from its original installation position and installed on a dedicated workbench for flushing and cleaning. This method is cumbersome to disassemble and assemble, and requires a certain amount of spare parts to maintain the normal operation of the system, so the time cost and hardware cost are very high. In addition, this method is usually a post-maintenance repair and cannot avoid the occurrence of failures.

[0005] The shutdown maintenance method refers to the suspension of normal operation of the actuator according to events (such as detection of servo valve core jam) or time conditions, and the execution of a specific cleaning procedure instead. This method reduces the effective working time of the system and reduces work efficiency.

[0006] The hardware redundancy method refers to adding additional hardware devices. During normal operation, the hydraulic connection between the current servo valve and the actuator is cut off through a switching device, and the actuator is controlled by a backup system instead. This method does not affect the normal operation of the actuator, but requires the additional arrangement of a backup system and a switching device, which is more costly.

[0007] Due to various drawbacks, the above method is subject to many restrictions in its application in engineering practice, resulting in the inability to effectively alleviate the accumulation of impurities in the servo valve during the long-term operation of the servo system, thereby reducing the working life of the servo valve. Summary of the invention

[0008] The purpose of the present invention is to solve the deficiencies of the prior art and to provide a control method for effectively flushing the spool of a servo valve without affecting the normal operation of a servo system.

[0009] The technical solution of the present invention is as follows: A servo valve anti-pollution control method, comprising:

[0010] S10: Establishing a real-time control model of the servo system according to the response characteristics of the servo valve and the actuator;

[0011] S20: obtaining an estimated value of the working state of the servo system at the current moment according to the real-time control model and the observed value of the working state of the servo system at the current moment;

[0012] S30: determining a control mode of the servo system according to a cleaning requirement and a control state of the servo system, wherein the control mode includes a cleaning mode and a performance mode;

[0013] S40: Determine the control input signal of the servo valve according to the estimated value and control mode of the servo system at the current moment.

[0014] Furthermore, in step S10, the real-time control model includes:

[0015] x k+1 =Ax k +Bu k

[0016] z k =Cx k

[0017] Among them, vector x represents the working state of the servo system, x = [svdi lpv ] T , s represents the displacement of the actuator, v represents the moving speed of the actuator, d represents the position of the servo valve core, i lpv Indicates the servo valve input electrical signal at the last moment;

[0018] u=i is the input signal of the servo system, i is the input electrical signal of the servo valve, z=s is the measurement signal of the servo system, and k represents the time;

[0019] A represents the state transfer matrix of the system, B represents the input matrix of the servo system, and C represents the identity matrix.

[0020] Furthermore, the state transfer matrix, input matrix and identity matrix are respectively:

[0021]

[0022]

[0023] C =

[100]

[0024] Among them, T c represents the control period of the controller, T p Indicates the time constant of the actuator, K p Indicates the gain of the actuator relative to the servo valve core, T s Indicates the time constant of the servo valve spool, K s Indicates the gain of the servo valve spool relative to the control current.

[0025] Furthermore, the step S20 includes:

[0026] Obtaining an observation value of the working state of the servo system at the current moment, wherein the observation value is a detection value of a displacement sensor of the actuator;

[0027] Estimate the actual working state of the servo system and obtain an estimated value of the working state of the servo system;

[0028] According to the estimated value of the working state of the servo system at the previous moment and the real-time control model, the predicted value of the working state of the servo system at the current moment is predicted.

[0029] Further, estimating the actual working state of the servo system to obtain an estimated value of the working state of the servo system includes:

[0030]

[0031] in, represents the estimated value of the servo system working state, L is the observer gain matrix, z k represents the observed value of the system servo working status, represents the predicted value of the servo system working state, C represents the unit matrix, and k represents the time;

[0032] The predicted value of the working state of the servo system at the current moment is predicted based on the estimated value of the working state of the servo system at the previous moment and the real-time control model, including:

[0033]

[0034] represents the predicted value of the servo system working state at time k, represents the estimated value of the servo system working state at time k-1, A represents the state transfer matrix of the system, B represents the input matrix of the servo system, u k-1Represents the input signal of the servo system at time k-1.

[0035] Furthermore, the step S30 includes:

[0036] The control state of the servo system includes a steady state and a dynamic state. When the control state of the servo system is in a steady state and the servo system needs to be cleaned, the servo system executes a cleaning mode, otherwise it executes a performance mode.

[0037] Furthermore, when ss is satisfied dem ≤δ and lasts for T enable time, determining that the control state of the servo system is a steady state, otherwise determining that the control state of the servo system is a dynamic state;

[0038] Where s represents the displacement of the actuator, s dem Indicates the target value of the actuator displacement, δ, T enable They are respectively the judgment threshold and confirmation time of the servo system control status criterion.

[0039] Furthermore, the step S40 includes:

[0040] Generate a state reference value of the servo system within N control cycles according to a control mode of the servo system;

[0041] According to the estimated value of the servo system state at the current moment, the servo system state within N consecutive control cycles is predicted to obtain the state prediction value within the N control cycles;

[0042] A quadratic programming equation is established based on the state prediction value, state reference value, valve core displacement characteristics, and actuator displacement characteristics within N control cycles to determine the optimal output vector of the quadratic programming equation, wherein the first item of the optimal output vector is the control input signal of the servo valve.

[0043] Further, generating a state reference value of the servo system within a prediction period according to the control mode of the servo system includes:

[0044] x ref,k+j =[s ref,k+j v ref,k+j d ref,k+j i ref,k+j-1 ] T

[0045] Among them, x ref,k+j represents the state reference value at time k+j, s ref,k+j represents the reference displacement value of the actuator at time k+j, v ref,k+j Indicates the reference value of the moving speed of the actuator at time k+j, d ref,k+j represents the reference value of the servo valve core position at time k+j, iref,k+j-1 represents the reference value of the servo valve input electrical signal at time k+j-1;

[0046] When the control mode is performance mode:

[0047]

[0048] When the control mode is cleaning mode:

[0049]

[0050] Among them, f(k,j) is the expected response trajectory of the servo system displacement, and g(k,j) is the cleaning waveform function.

[0051] Furthermore, the quadratic programming equation is:

[0052]

[0053] stx k+j ∈[x min ,x max ],j=1,2,...,N

[0054] in,

[0055] U=[u k u k+1 …u k+N-1 ] T is the independent variable of the quadratic programming equation, representing the input signal of the servo system within N consecutive control cycles starting from time k, p is the weight factor of the displacement following error of the servo valve spool, q is the weight factor of the displacement following error of the actuator, and r is the weight factor of the servo valve input electrical signal;

[0056] x min =[s dem +ηΔs min v min d min i min ] T is the lower limit of the deviation between the predicted state value and the state reference value of the servo system;

[0057] x max =[s dem +ηΔs max v max d max i max ] T is the upper limit of the deviation between the predicted state value and the state reference value of the servo system;

[0058] Among them, s dem Indicates the target value of the actuator displacement, Δs min, Δs max Respectively represent the lower and upper limits of the displacement of the actuator, v min 、v max Respectively represent the lower and upper limits of the moving speed of the actuator, d min d max Respectively represent the lower limit and upper limit of the servo valve core position, i min 、i max They respectively represent the lower limit and upper limit of the servo valve input electrical signal, and η is the safety margin coefficient.

[0059] The beneficial effects of the present invention are as follows:

[0060] This method is based on the principle of model predictive control. It uses the mathematical model of the servo valve and the actuator to perform real-time prediction and calculation through the controller. On the premise of ensuring that the actual response of the actuator meets the control expectations, the servo valve spool position is adjusted to perform periodic reciprocating motion, thereby realizing automatic cleaning of the servo valve during normal operation, improving the self-flushing ability of the servo valve, and effectively preventing the occurrence of servo valve spool jamming and other faults caused by contamination.

[0061] The present invention realizes the periodic reciprocating motion of the servo valve core through a model prediction algorithm, effectively slows down the accumulation speed of impurities in the working medium inside the servo valve, prolongs the working life of the servo valve, and improves the durability and reliability of the servo system.

[0062] The present invention effectively limits the disturbance caused by the servo valve core action on the control of the actuator by adding a constraint equation for the displacement fluctuation of the actuator in the algorithm, realizes the flushing and cleaning of the servo valve during normal operation, reduces the frequency of off-site maintenance and shutdown maintenance, and improves the working efficiency of the entire servo system.

[0063] The present invention can realize flushing and cleaning of the servo valve in operation without changing the hardware state or adding additional hardware devices, thereby effectively reducing the design and manufacturing costs of the servo system. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 It is a flow chart of the present invention.

[0065] Figure 2 is a schematic diagram of a typical servo system including a servo valve.

[0066] Figure 3 A response curve of the servo valve core displacement in a specific embodiment of the present invention.

[0067] Figure 4 Response curve of the displacement of the actuator in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0068] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. The described embodiment is only a part of the embodiment of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0069] In one technical solution of the present invention, Figure 2 The figure is a schematic diagram of a typical servo system including a servo valve and an actuator. The present invention provides a servo valve anti-pollution control method without changing the hardware state. Figure 1 This is a flowchart provided according to the specific process of the present invention. Figure 1 As shown, the present invention specifically includes:

[0070] S10: Establish a real-time control model of the servo system based on the response characteristics of the servo valve and the actuator.

[0071] A real-time model of the servo system is established, where the real-time model includes the response characteristics of components such as servo valves and actuators. The model can run in real time in the controller. At time k, the real-time control model of the servo system is defined as:

[0072] x k+1 =Ax k +Bu k

[0073] z k =Cx k

[0074] Among them, vector x represents the working state of the servo system, x = [svdi lpv ] T , s represents the displacement of the actuator, v represents the moving speed of the actuator, d represents the position of the servo valve core, i lpv Indicates the servo valve input electrical signal at the last moment;

[0075] u=i is the input signal of the servo system, i is the input electrical signal of the servo valve, z=s is the measurement signal of the servo system, and k represents the time;

[0076] A represents the state transfer matrix of the system, B represents the input matrix of the servo system, and C represents the identity matrix.

[0077] Among them, the state transfer matrix, input matrix and identity matrix are respectively:

[0078]

[0079]

[0080] C =

[100]

[0081] Among them, T c represents the control period of the controller, T p Indicates the time constant of the actuator, K p Indicates the gain of the actuator relative to the servo valve core, T s Indicates the time constant of the servo valve spool, K s Indicates the gain of the servo valve spool relative to the control current.

[0082] The values ​​of the model parameters in matrices A and B are shown in Table 1.

[0083] Table 1

[0084]

[0085] S20: Obtain an estimated value of the working state of the servo system at the current moment according to the real-time control model and the observed value of the working state of the servo system at the current moment.

[0086] The observed value of the working state of the servo system at the current moment is obtained, where the observed value is the detection value of the displacement sensor of the actuator.

[0087] Obtain the observed value of the working state of the servo system at time k, and obtain z through the displacement sensor of the actuator k .

[0088] The actual working state of the servo system is estimated to obtain an estimated value of the working state of the servo system.

[0089] Construct the Lumberg observer to estimate the actual working state of the servo system at time k:

[0090]

[0091] in, represents the estimated value of the servo system working state, L is the observer gain matrix, z k represents the observed value of the system servo working status, represents the predicted value of the servo system working state, C represents the unit matrix, and k represents the time. Among them, the value of L is L=[0.5200.50] T .

[0092] According to the estimated value of the working state of the servo system at the previous moment and the real-time control model, the predicted value of the working state of the servo system at the current moment is predicted.

[0093]

[0094] represents the predicted value of the servo system working state at time k, represents the estimated value of the servo system working state at time k-1, A represents the state transfer matrix of the system, B represents the input matrix of the servo system, u k-1 Represents the input signal of the servo system at time k-1.

[0095] It should be noted that obtaining the predicted value of the servo system working state at time k requires the estimated value at time k-1, and obtaining the estimated value at time k-1 requires the predicted value at time k-1.

[0096] S30: Determine a control mode of the servo system according to a cleaning requirement and a control state of the servo system, wherein the control mode includes a cleaning mode and a performance mode.

[0097] The control state of the servo system includes a steady state and a dynamic state.

[0098] Identify the control state of the servo system. When ss is satisfied dem ≤δ and lasts for T enable time, determining that the control state of the servo system is a steady state, otherwise determining that the control state of the servo system is a dynamic state;

[0099] Where s represents the displacement of the actuator, s dem Indicates the target value of the actuator displacement, δ, T enable They are respectively the judgment threshold and confirmation time of the servo system control status criterion.

[0100] Identify the cleaning requirement of the servo system, and consider the cleaning requirement to always be met or determine the cleaning requirement based on the pollution status of the servo system or determine the cleaning requirement based on the running time of the servo system. In this example, it is considered that the cleaning requirement is always met during the working process.

[0101] When the control state of the servo system is in a steady state and the servo system needs to be cleaned, the servo system executes the cleaning mode, otherwise it executes the performance mode.

[0102] S40: Determine the control input signal of the servo valve according to the estimated value and control mode of the servo system at the current moment.

[0103] According to the control mode of the servo system, a state reference value of the servo system within N control cycles is generated.

[0104] x ref,k+j =[s ref,k+j v ref,k+j d ref,k+j i ref,k+j-1 ] T

[0105] Among them, xref,k+j represents the state reference value at time k+j, s ref,k+j represents the reference displacement value of the actuator at time k+j, v ref,k+j Indicates the reference value of the moving speed of the actuator at time k+j, d ref,k+j represents the reference value of the servo valve core position at time k+j, i ref,k+j-1 Represents the reference value of the servo valve input electrical signal at time k+j-1.

[0106] When the control mode is performance mode:

[0107]

[0108] When the control mode is cleaning mode:

[0109]

[0110] Among them, f(k,j) is the expected response trajectory of the servo system displacement, and g(k,j) is the cleaning waveform function.

[0111] in A triangular waveform cleaning function is used, β is an algorithm parameter, the values ​​are shown in Table 2, indicating the amplitude of the cleaning waveform, λ is an algorithm parameter, the values ​​are shown in Table 2, indicating the period of the cleaning waveform, and % indicates the remainder operation.

[0112] g(k,i)=αs ref,k+i-1 +(1-α)s dem ,s dem is the expected value of the actuator position at the current moment, s ref,k+i-1 represents the displacement reference value of the actuator at time k+i-1, α is the algorithm parameter, and its value is shown in Table 2, which represents the expected servo system response characteristics. In particular, the initial value is the estimated value of the servo system state Item 1 of .

[0113] According to the estimated value of the servo system state at the current moment, the servo system state within N consecutive control cycles is predicted to obtain the state prediction value within the N control cycles.

[0114] Specifically, for any j = 1, 2, ..., N, x k+j =A j x k +A j-1 Bu k +…+Bu k+j-1 .

[0115] A quadratic programming equation is established based on the state prediction value, state reference value, valve core displacement characteristics, and actuator displacement characteristics within N control cycles to determine the optimal output vector of the quadratic programming equation, wherein the first item of the optimal output vector is the control input signal of the servo valve.

[0116] Wherein, the quadratic programming equation is:

[0117]

[0118] stx k+j ∈[x min ,x max ],j=1,2,...,N

[0119] in,

[0120] U=[u k u k+1 …u k+N-1 ] T is the independent variable of the quadratic programming equation, which represents the input signal of the servo system within N consecutive control cycles starting from time k, p is the weight factor of the servo valve spool displacement following error, q is the weight factor of the actuator displacement following error, and r is the weight factor of the servo valve input electrical signal.

[0121] Among them, d k+j -d ref，k+j It represents the difference between the expected control position of the servo valve at time k+j and the actual position of the servo valve.

[0122] S k+j -S ref，k+j It represents the difference between the predicted control position of the actuator at time k+j and the actual position of the servo valve.

[0123] u k+j-1 Represents the input signal of the servo system of the servo valve at time k+j-1.

[0124] x min =[s dem +ηΔs min v min d min i min ] T is the lower limit of the deviation between the predicted state value and the state reference value of the servo system;

[0125] x max =[s dem +ηΔs max v max d max i max ] T is the upper limit of the deviation between the predicted state value and the state reference value of the servo system;

[0126] Among them, s dem Indicates the target value of the actuator displacement, Δs min , Δs max Respectively represent the lower and upper limits of the displacement of the actuator, v min 、v max Respectively represent the lower and upper limits of the moving speed of the actuator, d min d max Respectively represent the lower limit and upper limit of the servo valve core position, i min 、i max They represent the lower limit and upper limit of the servo valve input electrical signal respectively, and η is the safety margin coefficient, which is used to prevent the actual system state from exceeding the limit due to estimation error, prediction error and control fluctuation.

[0127] Select vector U * The first item in is used as the control input of the servo valve at the current moment, where U * is the optimal solution found in the quadratic programming equation.

[0128] The specific algorithm parameters in the embodiment of the present invention are as follows:

[0129] Table 2 Control algorithm parameter values

[0130]

[0131] In this embodiment, the initial parameters are set as follows:

[0132] Table 3 Initial parameters of the embodiment

[0133]

[0134] At the initial moment, set the target value s of the actuator displacement dem is 0mm, and is adjusted to 5mm at 0.5s. The working mode of the servo system is determined according to step S30:

[0135] 1) During the 0-0.5s period, the servo system works in the "cleaning mode" and the lower limit of the displacement of the actuator is Δs min , upper limit value Δs max Take -2mm and 2mm respectively, and the reference value of the servo valve core position d ref The change of the triangular waveform is shown. Through the control algorithm of the present invention, on the one hand, the displacement s of the actuator remains relatively stable, and on the other hand, the position d of the servo valve core follows its reference value d well. ref , indicating that the system can fully move the servo valve core to achieve servo valve cleaning while limiting the disturbance of the actuator, so that the servo system can work stably. The displacement of the actuator in this process is shown in Figure 3 , the performance of the servo valve spool position Figure 4 shown.

[0136] 2) During the period of 0.5-0.71s, the system works in the “performance mode”, and the lower and upper limits of the displacement of the actuator are Δs min , Δs max Take -10 respectively 6 mm, 10 6 mm, at this time the displacement of the actuator responds quickly and accurately s dem The change of displacement ensures that the servo system has excellent following performance for the displacement target value. Figure 3 shown.

[0137] 3) After 0.71s, the system returns to "cleaning mode".

[0138] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A servo valve anti-pollution control method, characterized in that: include: S10: Establishing a real-time control model of the servo system according to the response characteristics of the servo valve and the actuator; S20: obtaining an estimated value of the working state of the servo system at the current moment according to the real-time control model and the observed value of the working state of the servo system at the current moment; S30: determining a control mode of the servo system according to a cleaning requirement and a control state of the servo system, wherein the control mode includes a cleaning mode and a performance mode; S40: Determine the control input signal of the servo valve according to the estimated value and control mode of the servo system at the current moment.

2. The servo valve anti-pollution control method according to claim 1, characterized in that: In step S10, the real-time control model includes: x k+1 =Ax k +Bu k from k =Cx k Among them, vector x represents the working state of the servo system, x = [svdi lpv ] T , s represents the displacement of the actuator, v represents the moving speed of the actuator, d represents the position of the servo valve core, i lpv Indicates the servo valve input electrical signal at the last moment; u=i is the input signal of the servo system, i is the input electrical signal of the servo valve, z=s is the measurement signal of the servo system, and k represents the time; A represents the state transfer matrix of the system, B represents the input matrix of the servo system, and C represents the identity matrix.

3. The servo valve anti-pollution control method according to claim 2, characterized in that: The state transfer matrix, input matrix and identity matrix are respectively: Among them, T c represents the control period of the controller, T p Indicates the time constant of the actuator, K p Indicates the gain of the actuator relative to the servo valve core, T s Indicates the time constant of the servo valve spool, K s Indicates the gain of the servo valve spool relative to the control current.

4. The servo valve anti-pollution control method according to claim 1, characterized in that: The step S20 comprises: Obtaining an observation value of the working state of the servo system at the current moment, wherein the observation value is a detection value of a displacement sensor of the actuator; Estimate the actual working state of the servo system and obtain an estimated value of the working state of the servo system; According to the estimated value of the working state of the servo system at the previous moment and the real-time control model, the predicted value of the working state of the servo system at the current moment is predicted.

5. The servo valve anti-pollution control method according to claim 4, characterized in that: The estimating the actual working state of the servo system and obtaining the estimated value of the working state of the servo system comprises: in, represents the estimated value of the servo system working state, L is the observer gain matrix, z k represents the observed value of the system servo working status, represents the predicted value of the servo system working state, C represents the unit matrix, and k represents the time; The predicted value of the working state of the servo system at the current moment is predicted based on the estimated value of the working state of the servo system at the previous moment and the real-time control model, including: represents the predicted value of the servo system working state at time k, represents the estimated value of the servo system working state at time k-1, A represents the state transfer matrix of the system, B represents the input matrix of the servo system, u k-1 Represents the input signal of the servo system at time k-1.

6. The servo valve anti-pollution control method according to claim 1, characterized in that: The step S30 comprises: The control state of the servo system includes a steady state and a dynamic state. When the control state of the servo system is in a steady state and the servo system needs to be cleaned, the servo system executes a cleaning mode, otherwise it executes a performance mode.

7. The servo valve anti-pollution control method according to claim 6, characterized in that: When ss is met dem |≤δ and lasts for T enable time, determining that the control state of the servo system is a steady state, otherwise determining that the control state of the servo system is a dynamic state; Where s represents the displacement of the actuator, s dem Indicates the target value of the actuator displacement, δ, T enable They are respectively the judgment threshold and confirmation time of the servo system control status criterion.

8. The servo valve anti-pollution control method according to claim 1, characterized in that: The step S40 comprises: Generate a state reference value of the servo system within N control cycles according to a control mode of the servo system; According to the estimated value of the servo system state at the current moment, the servo system state within N consecutive control cycles is predicted to obtain the state prediction value within the N control cycles; A quadratic programming equation is established based on the state prediction value, state reference value, valve core displacement characteristics, and actuator displacement characteristics within N control cycles to determine the optimal output vector of the quadratic programming equation, wherein the first item of the optimal output vector is the control input signal of the servo valve.

9. The servo valve anti-pollution control method according to claim 8, characterized in that: The step of generating a state reference value of the servo system within a prediction period according to the control mode of the servo system comprises: x ref,k+j =[s ref,k+j v ref,k+j d ref,k+j i ref,k+j-1 ] T Among them, x ref,k+j represents the servo system state reference value at time k+j, s ref,k+j represents the reference displacement value of the actuator at time k+j, v ref,k+j Indicates the reference value of the moving speed of the actuator at time k+j, d ref,k+j represents the reference value of the servo valve core position at time k+j, i ref,k+j-1 represents the reference value of the servo valve input electrical signal at time k+j-1; When the control mode is performance mode: When the control mode is cleaning mode: Among them, f(k,j) is the expected response trajectory of the servo system displacement, and g(k,j) is the cleaning waveform function.

10. The servo valve anti-pollution control method according to claim 8, characterized in that: The quadratic programming equation is: in, U=[u k u k+1 ...u k+N-1 ] T is the independent variable of the quadratic programming equation, representing the input signal of the servo system within N consecutive control cycles starting from time k, p is the weight factor of the displacement following error of the servo valve spool, q is the weight factor of the displacement following error of the actuator, and r is the weight factor of the servo valve input electrical signal; x min =[s dem +ηΔs min v min d min i min ] T is the lower limit of the deviation between the predicted state value and the state reference value of the servo system; x max =[s dem +ηΔs max v max d max i max ] T is the upper limit of the deviation between the predicted state value and the state reference value of the servo system; Among them, s dem Indicates the target value of the actuator displacement, Δs min , Δs max Respectively represent the lower and upper limits of the displacement of the actuator, v min 、v max Respectively represent the lower and upper limits of the moving speed of the actuator, d min ,d max Respectively represent the lower limit and upper limit of the servo valve core position, i min 、i max They respectively represent the lower limit and upper limit of the servo valve input electrical signal, and η is the safety margin coefficient.

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