Adaptive control method and device based on erosion wear compensation

Abstract

The present disclosure relates to an adaptive control method and device based on erosion wear compensation. The adaptive control method based on erosion wear compensation comprises: performing finite element simulation on a fluid domain of a hydraulic valve, and fitting an erosion rate function of the hydraulic valve; establishing a throttle coefficient prediction model of the hydraulic valve based on the erosion rate function and the throttle coefficient before erosion; establishing a mathematical model of a hydraulic system, and designing an adaptive law and a controller based on the mathematical model; wherein the hydraulic system comprises the hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system; establishing an erosion wear compensation model of the hydraulic system based on the throttle coefficient prediction model and the mathematical model; and using the adaptive law, the controller and the erosion wear compensation model to perform adaptive control on the output voltage of the hydraulic system. The present disclosure can use the erosion wear compensation model to perform adaptive control on the output voltage of the hydraulic system under the action of the adaptive law and the controller.

Description

Technical Field

[0001] The present disclosure relates to the technical field of compensation control, and in particular to an adaptive control method and device based on erosion wear compensation. Background Art

[0002] Erosive wear refers to the phenomenon that solid particles violently impact the surface of a material at a certain angle and speed, causing the surface material to fatigue and then fall off.

[0003] Hydraulic valves are widely used in various fields, including aerospace and shipbuilding. In recent years, with the increasing demand for control precision, valve performance and service life have become increasingly prominent. The geometric accuracy of the working edge of a hydraulic valve orifice directly affects its performance. As the valve operates, erosion and wear of the working edge of the valve orifice will occur, which will seriously affect the control accuracy and service life of the valve. Summary of the Invention

[0004] In view of this, an embodiment of the present disclosure provides an adaptive control method and device based on erosion wear compensation to solve the problems existing in the related art.

[0005] A first aspect of the embodiments of the present disclosure provides an adaptive control method based on erosion wear compensation, comprising:

[0006] Performing finite element simulation on the fluid domain of the hydraulic valve to obtain an erosion rate function of the hydraulic valve by fitting;

[0007] Establishing a throttling coefficient prediction model based on the erosion rate function and the throttling coefficient before erosion;

[0008] Establishing a mathematical model of a hydraulic system, and designing an adaptive law and a controller based on the mathematical model; wherein the hydraulic system includes the hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system;

[0009] Establishing an erosion wear compensation model for the hydraulic system based on the throttling coefficient prediction model and the mathematical model;

[0010] The hydraulic system is adaptively controlled by utilizing the adaptive law, the controller and the erosion wear compensation model.

[0011] A second aspect of the embodiments of the present disclosure provides an adaptive control device based on erosion wear compensation, comprising:

[0012] A simulation module, configured to perform finite element simulation on a fluid domain of a hydraulic valve and obtain an erosion rate function of the hydraulic valve by fitting;

[0013] The construction module is further configured to establish a mathematical model of the hydraulic system, and design an adaptive law and a controller based on the mathematical model, wherein the hydraulic system comprises the hydraulic valve, and the mathematical model is used to describe working principles of the hydraulic system.

[0014] The construction module is further configured to establish a mathematical model of the hydraulic system, and design an adaptive law and a controller based on the mathematical model, wherein the hydraulic system comprises the hydraulic valve, and the mathematical model is used to describe working principles of the hydraulic system.

[0015] The construction module is further configured to establish an erosion wear compensation model of the hydraulic system based on the throttle coefficient prediction model and the mathematical model.

[0016] The control module is configured to perform adaptive control on an output voltage of the hydraulic system by using the adaptive law, the controller and the erosion wear compensation model.

[0017] A third aspect of the embodiments of the present disclosure provides an electronic device, comprising:

[0018] at least one processor;

[0019] a memory for storing at least one processor-executable instruction;

[0020] The at least one processor is configured to execute the instructions to implement the steps of the above method.

[0021] A fourth aspect of the embodiments of the present disclosure provides a computer-readable storage medium, when instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to perform the steps of the above method.

[0022] The above at least one technical solution adopted by the embodiments of the present disclosure can achieve the following beneficial effects: the erosion rate function of the hydraulic valve is fitted by performing finite element simulation on the fluid domain of the hydraulic valve; the throttle coefficient prediction model of the hydraulic valve is established based on the erosion rate function and the throttle coefficient before erosion; the mathematical model of the hydraulic system is established, and the adaptive law and the controller are designed based on the mathematical model; wherein the hydraulic system comprises the hydraulic valve, and the mathematical model is used to describe the working principles of the hydraulic system; the erosion wear compensation model of the hydraulic system is established based on the throttle coefficient prediction model and the mathematical model; and the output voltage of the hydraulic system is adaptively controlled by using the adaptive law, the controller and the erosion wear compensation model. The throttle coefficient prediction model of the hydraulic valve is established, the mathematical model of the hydraulic system is established and the adaptive law and the controller are designed, and then the erosion wear compensation model of the hydraulic system is established based on the throttle coefficient prediction model and the mathematical model. Under the action of the adaptive law and the controller, the output voltage of the hydraulic system is adaptively controlled by using the erosion wear compensation model, so as to improve the control precision of the hydraulic valve and prolong the service life of the hydraulic valve. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative effort based on these drawings.

[0024] Figure 1 A flowchart of the adaptive control method based on erosion wear compensation provided by the exemplary embodiments of the present disclosure is shown;

[0025] Figure 2 A schematic diagram of the overall control framework of the hydraulic system provided by the exemplary embodiments of the present disclosure is shown;

[0026] Figure 3A A schematic diagram of the overall control framework of the hydraulic system provided by the exemplary embodiments of the present disclosure is shown;

[0027] Figure 3B A schematic diagram of the overall control framework of the hydraulic system provided by the exemplary embodiments of the present disclosure is shown;

[0028] Figure 4 A profile diagram of the erosion wear of the hydraulic valve provided by the exemplary embodiments of the present disclosure is shown;

[0029] Figure 5A A schematic diagram of the control method of the hydraulic system provided by the conventional method is shown;

[0030] Figure 5B A schematic diagram of the control method of the hydraulic system provided by the exemplary embodiments of the present disclosure is shown;

[0031] Figure 6 A control effect diagram of the adaptive control method based on erosion wear compensation provided by the exemplary embodiments of the present disclosure is shown;

[0032] Figure 7 A schematic diagram of the adaptive control device based on erosion wear compensation provided by the exemplary embodiments of the present disclosure is shown;

[0033] Figure 8 A schematic diagram of the electronic device provided by the exemplary embodiments of the present disclosure is shown;

[0034] Figure 9 A schematic diagram of the computer system provided by the exemplary embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0035] Embodiments of the present disclosure will be described below in greater detail with reference to the accompanying drawings. While certain embodiments of the present disclosure are shown in the drawings, it is understood that the present disclosure can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein, but rather should be construed to encompass all modifications equivalent in meaning and scope. It is understood that the drawings and embodiments of the present disclosure are only for illustrative purposes and are not intended to limit the scope of protection of the present disclosure.

[0036] It should be understood that each step described in the method embodiments of the present disclosure can be performed in different orders and / or in parallel. In addition, the method embodiments can include additional steps and / or omit the steps shown. The scope of the present disclosure is not limited in this respect.

[0037] The term "comprising" and variations thereof as used herein are open-ended, that is "including but not limited to". The term "based on" is "based, at least in part, on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Related terms are defined as follows. It should be noted that the concepts mentioned in the present disclosure are merely illustrative and not restrictive, and those skilled in the art should understand that "one", "multiple" modification is illustrative and not restrictive, and unless otherwise explicitly stated in the context, it should be understood as "one or more".

[0038] It should be noted that the "one", "multiple" modification mentioned in the present disclosure is illustrative and not restrictive, and those skilled in the art should understand that unless otherwise explicitly stated in the context, it should be understood as "one or more".

[0039] The names of the messages or information exchanged between the devices in the embodiments of the present disclosure are only for illustrative purposes, and are not intended to limit the scope of the messages or information.

[0040] The adaptive control method based on erosion wear compensation provided by the embodiments of the present disclosure can be executed by a terminal or a chip applied to the terminal.

[0041] For example, the terminal described above can include one or more of a mobile phone, a tablet computer, a wearable device, a vehicle-mounted device, a notebook computer, an ultra-mobile personal computer (UMPC), a netbook, a Personal Digital Assistant (PDA), etc., and the exemplary embodiments of the present disclosure do not specifically limit this.

[0042] Figure 1A flowchart of an adaptive control method based on erosion wear compensation provided by an example embodiment of the present disclosure is shown. As shown in Figure 1 The adaptive control method based on erosion wear compensation includes the following steps.

[0043] S101, finite element simulation is performed on the fluid domain of the hydraulic valve, and an erosion rate function of the hydraulic valve is fitted;

[0044] S102, a throttle coefficient prediction model of the hydraulic valve is established based on the erosion rate function and the throttle coefficient before erosion;

[0045] S103, a mathematical model of the hydraulic system is established, and an adaptive law and a controller are designed based on the mathematical model; wherein the hydraulic system includes the hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system;

[0046] S104, an erosion wear compensation model of the hydraulic system is established based on the throttle coefficient prediction model and the mathematical model;

[0047] S105, the output voltage of the hydraulic system is adaptively controlled by using the adaptive law, the controller, and the erosion wear compensation model.

[0048] Specifically, the method of the example embodiment of the present disclosure is described by taking the hydraulic system as a valve-controlled cylinder system, and taking the hydraulic valve of the valve-controlled cylinder system as a proportional servo valve. Figure 2 A schematic diagram of the valve-controlled cylinder system provided by an example embodiment of the present disclosure is shown. As shown in Figure 2 The example embodiment of the present disclosure takes the rod displacement of the hydraulic cylinder 201 as the object, at a certain time, the displacement sensor 205 reads the rod displacement at this time, and transmits the information to the control system 204, the control system 204 compares the rod displacement with the expected displacement to obtain the displacement deviation, and the control system 204 outputs a control voltage to the proportional servo valve 202 according to the displacement deviation and a certain control strategy, changes the flow rate from the oil tank 203 to the proportional servo valve 202, and then realizes the control of the rod displacement.

[0049] In actual application, the example embodiment of the present disclosure can draw the fluid domain of the valve cavity of the proportional servo valve by using the Boolean operation idea, perform finite element simulation on the fluid domain to obtain the finite element simulation result, and then fit the finite element simulation result to obtain the erosion rate function of the hydraulic valve.

[0050] At this time, the throttle coefficient of the hydraulic valve before erosion can be obtained, and a throttle coefficient prediction model of the hydraulic valve is established based on the erosion rate function and the throttle coefficient before erosion.

[0051] Meanwhile, the example embodiments of the present disclosure can establish a mathematical model of the hydraulic system, and design an adaptive law and a controller based on the mathematical model, wherein the hydraulic system comprises a hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system.

[0052] Based on this, the example embodiments of the present disclosure can also establish an erosion wear compensation model of the hydraulic system based on the throttle coefficient prediction model and the mathematical model, and use the adaptive law, the controller and the erosion wear compensation model to perform adaptive control on the output voltage of the hydraulic system.

[0053] Figure 3A FIG. 1 shows a schematic diagram of the overall control framework of the hydraulic system provided by the conventional method, Figure 3B FIG. 2 shows a schematic diagram of the overall control framework of the hydraulic system provided by the example embodiments of the present disclosure. Figure 3A And Figure 3B It can be seen that, compared with the conventional method, the example embodiments of the present disclosure establish a throttle coefficient prediction model for the hydraulic valve in the hydraulic system, and establish an erosion wear compensation model of the hydraulic valve in combination with the mathematical model of the hydraulic system, and then use the adaptive law, the controller and the erosion wear compensation model to perform adaptive control on the output voltage of the hydraulic system.

[0054] It should be noted that, since the erosion wear mainly causes the flow leakage of the hydraulic valve, the more accurate the throttle coefficient prediction model is, the more accurate the control on the output voltage of the hydraulic system is theoretically. According to the selected model of the hydraulic valve, the mathematical model of the entire hydraulic system is established, and in order to improve the compensation accuracy, the mathematical modeling of the hydraulic valve can be as detailed as possible.

[0055] When designing the adaptive law and the robust controller, the parameters that need to be adapted can be selected according to the characteristics of the hydraulic valve, the adaptive law is designed based on the discontinuous projection (other suitable methods can be used), and the robust controller is designed according to the overall system.

[0056] According to the technical scheme of the example embodiment of the present disclosure, the erosion rate function of the hydraulic valve is fitted by performing finite element simulation on the fluid domain of the hydraulic valve; the throttle coefficient prediction model of the hydraulic valve is established based on the erosion rate function and the throttle coefficient before erosion; the mathematical model of the hydraulic system is established, and the adaptive law and the controller are designed based on the mathematical model; wherein the hydraulic system comprises the hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system; the erosion wear compensation model of the hydraulic system is established based on the throttle coefficient prediction model and the mathematical model; the output voltage of the hydraulic system is adaptively controlled by using the adaptive law, the controller and the erosion wear compensation model, the throttle coefficient prediction model of the hydraulic valve is established, the mathematical model of the hydraulic system is established, the adaptive law and the controller are designed, and then the erosion wear compensation model of the hydraulic system is established based on the throttle coefficient prediction model and the mathematical model, under the action of the adaptive law and the controller, the output voltage of the hydraulic system is adaptively controlled by using the erosion wear compensation model, so as to improve the control precision of the hydraulic valve and prolong the service life of the hydraulic valve.

[0057] In some embodiments, the erosion rate function of the hydraulic valve is fitted by performing finite element simulation on the fluid domain of the hydraulic valve, which can include:

[0058] The erosion rate under a plurality of different valve opening degrees and working pressure differences is obtained by performing finite element simulation on the fluid domain of the hydraulic valve.

[0059] The erosion rate under a plurality of different valve opening degrees and working pressure differences is fitted by using the E / CRC wear model to obtain the erosion rate function of the hydraulic valve.

[0060] Specifically, the erosion wear rate of the valve port of the hydraulic valve can be calculated by FLUENT. The erosion rate under different valve opening degrees and working pressure differences can be obtained by a large number of finite element analysis (FEA) calculations, and the erosion rate expression, that is, the erosion rate function of the hydraulic valve, can be obtained after fitting.

[0061] Exemplarily, the flowing oil is taken as a continuous phase, and the solid particles in the oil are taken as discrete items. The flow field distribution of the continuous phase and the motion trajectory of the discrete items in the Lagrangian coordinate system are simulated. The velocity, impact angle and other parameters of the discrete items are obtained by integration, which are brought into the E / CRC model to calculate the erosion wear rate.

[0062] The E / CRC wear model can be represented by the following formula (1):

[0063]

[0064] Wherein, E R represents the E / CRC wear model, represents the mass flow rate of particles, N a represents the number of particles colliding per unit time, v represents the particle erosion velocity; S(t) represents the erosion wear area per unit time, b(v) represents the velocity index (generally taking the empirical value of 2.6), and C(d) represents the particle property function, which takes a value of 1.8×10 -9 ,f(θ α ) is the erosion angle function, and its value is a piecewise function;

[0065] The erosion rate function is expressed by the following formula (2):

[0066]

[0067] Where ER represents the erosion rate function, x v represents the valve opening, ΔP represents the working pressure difference, and the fitting degree of the erosion rate function is 0.90865.

[0068] In some embodiments, establishing a throttling coefficient prediction model for a hydraulic valve based on the erosion rate function and the throttling coefficient before erosion may include:

[0069] Obtaining the valve opening and erosion time of the hydraulic valve before erosion;

[0070] Calculate the valve opening of the hydraulic valve after erosion based on the valve opening before erosion, erosion time and erosion rate function;

[0071] A throttling coefficient prediction model for hydraulic valves is established based on the valve opening before erosion, the valve opening after erosion and the throttling coefficient before erosion.

[0072] Specifically, Figure 4 FIG. 1 shows a profile diagram of erosion wear of a hydraulic valve provided by an exemplary embodiment of the present disclosure. Figure 4 As shown in the figure, it is assumed that the erosion profile of the valve core 401 and the valve sleeve 402 of the hydraulic valve is a quarter circle, R1 and R2 represent the erosion wear profile fillet radius of the valve core and the valve sleeve respectively, d1 and d2 represent the erosion depth of the valve core and the valve sleeve respectively, and x v0 represents the valve opening before erosion; where R1 = R2 = R, and d1 = d2 = d. Then, based on the relationship between erosion mass loss, erosion depth, and the geometry of the valve opening after erosion, a prediction model for the throttling coefficient caused by erosion wear can be obtained.

[0073] In the method of the exemplary embodiment of the present disclosure, the valve opening after erosion can be expressed by the following formula (3):

[0074]

[0075] 10n 100The erosion wear mass of the valve port caused by one particle in the time Δt can be represented by the following formula (4):

[0076]

[0077] wherein M represents the erosion wear mass of the valve port, ER represents the erosion rate of the valve sleeve and the valve core, A represents the area of the erosion site of the throttling edge of the valve sleeve and the valve core, and Δt represents the erosion time.

[0078] The erosion depth of the valve port can be represented by the following formula (5):

[0079]

[0080] wherein d represents the erosion depth of the valve port, ρ v represents the density of the material of the valve core and the valve sleeve, and S represents the erosion wear area.

[0081] From the geometric relationship, the following formula (6) can be obtained:

[0082]

[0083] By combining the formula (3) to formula (6), the valve port opening after erosion is obtained. The valve port opening after erosion is calculated by the following formula (7):

[0084]

[0085] wherein x v ’ represents the valve port opening after erosion, x v0 represents the valve port opening before erosion, ER represents the erosion rate function, Δt represents the erosion time, and ρ v represents the material density of the valve core and the valve sleeve of the hydraulic valve.

[0086] At this time, the throttling coefficient before erosion can be obtained, and based on the valve port opening before erosion, the valve port opening after erosion, and the throttling coefficient before erosion, a throttling coefficient prediction model of the hydraulic valve is established. The throttling coefficient prediction model is represented by the following formula (8):

[0087]

[0088] wherein C V represents the throttling coefficient after erosion, C V0 represents the throttling coefficient before erosion, and other parameters are described above and will not be repeated here.

[0089] In some embodiments, adaptive control of the output voltage of the hydraulic system by using the adaptive law, the controller, and the erosion wear compensation model can include:

[0090] outputting a current voltage based on an adaptive law and a controller;

[0091] outputting a compensation voltage based on an erosion wear compensation model, the compensation voltage being related to a current erosion time and a current working condition;

[0092] compensating the current voltage by using the compensation voltage, the output voltage of the hydraulic system including the current voltage and the compensation voltage.

[0093] Specifically, according to the erosion wear mechanism, to eliminate the flow deviation caused by the erosion wear of the valve port, it is necessary to predict and compensate the output flow variation of the proportional servo valve.

[0094] Figure 5A a principle diagram of a control method of a hydraulic system provided by a traditional method is shown, Figure 5B a principle diagram of a control method of a hydraulic system provided by an example embodiment of the present disclosure is shown. By comparison Figure 5A and Figure 5B It can be seen that, compared with the traditional method, the example embodiment of the present disclosure can take the given time and the expected displacement of the rod as input, calculate the erosion wear after the throttling coefficient of the proportional servo valve after the erosion wear by the erosion wear compensation model, calculate the compensation voltage du based on the difference between the throttling coefficient after the erosion wear and the throttling coefficient before the erosion wear under the given time and working condition, compensate the current voltage u output by the controller by using the compensation voltage du, so that the output voltage of the hydraulic system includes the current voltage u and the compensation voltage du.

[0095] Based on this, the example embodiment of the present disclosure can establish the erosion wear compensation model of the hydraulic valve for the hydraulic valve in the hydraulic system, and then use the adaptive law, the controller and the erosion wear compensation model to adaptively control the output voltage of the hydraulic system, so as to improve the control accuracy of the hydraulic valve and prolong the service life of the hydraulic valve.

[0096] Figure 6 a control effect diagram of the adaptive control method based on the erosion wear compensation provided by the example embodiment of the present disclosure is shown. As Figure 6 shown, before the voltage compensation, the actual output flow peak value is much higher than the expected output due to the flow leakage; after the voltage compensation, the actual output flow peak value is closer to the expected output.

[0097] Taking the hydraulic system as a valve-controlled cylinder system and the hydraulic valve of the valve-controlled cylinder system as a proportional servo valve, the mathematical model of the valve-controlled cylinder system can include the following contents:

[0098] The mathematical model of the proportional servo valve can be represented by the following formula (9):

[0099] P c =K a *u (9)

[0100] where P c represents the control pressure of the spool valve core, K a represents the voltage gain, u represents the input voltage of the hydraulic valve (also the current voltage output by the controller).

[0101] The motion equation of the valve core can be represented by the following formula (10):

[0102]

[0103] where A2 represents the control pressure P c of the spool valve core, P out represents the feedback action area of the valve outlet pressure on the spool valve core, P t represents the pre-tightening force of the spool valve core, m v represents the mass of the spool valve core, y v represents the displacement of the spool valve core, y v The above “·” represents the first-order derivative, y v The above “··” represents the second-order derivative, C f represents the damping of the spool valve core, K f represents the spring stiffness of the spool valve core.

[0104] The flow of the proportional servo valve can be represented by the following formula (11):

[0105]

[0106] where: q v represents the valve outlet flow; C v represents the orifice coefficient; d m represents the valve port diameter; P s represents the oil source pressure; P oil represents the tank back pressure; and p represents the oil density.

[0107] The flow equation of the hydraulic cylinder can be represented by the following formula (12):

[0108]

[0109] where A g represents the effective action area of the hydraulic cylinder, Y represents the piston displacement of the hydraulic cylinder, C tp represents the total leakage coefficient of the hydraulic cylinder, P represents the pressure difference between the two chambers of the hydraulic cylinder, V t represents the total volume of the hydraulic cylinder, and βe represents the bulk modulus of the working fluid.

[0110] The motion equation of the hydraulic cylinder can be represented by the following formula (13):

[0111]

[0112] where m represents the total mass of the piston and load, B k represents the viscous damping coefficient of the variable cylinder piston and load, K f represents the spring stiffness of the load (spool valve core), and F represents the variable mechanism adjustment force.

[0113] Based on this, the example embodiments of the present disclosure can design adaptive laws and controllers based on mathematical models.

[0114] According to the principle of the system, the state variables are defined as follows:

[0115] In combination with the mathematical model of the valve-controlled cylinder system, the state space expression is as follows:

[0116]

[0117] where,

[0118] According to the influence of parameter changes on the system tracking effect and other dynamic characteristics during the operation of the system, the parameter variables are defined as follows:

[0119]

[0120] Substituting the parameter variables into the state space expression, the following formula is obtained:

[0121]

[0122] where,

[0123] It is assumed that the unknown parameter vector θ is in a known bounded set Ω, and:

[0124]

[0125] where θ min = [θ 1min , …, θ nmin ] T , θ max = [θ 1max , …, θ nmax ] T .

[0126] Let denote the estimated value of θ, denote the estimation error, i.e. An adaptive law based on discontinuous projection is designed as follows:

[0127]

[0128] where Γ denotes an adaptive law, and is a positive definite diagonal constant matrix: τ denotes an adaptive function. Define a discontinuous projection

[0129]

[0130] From (16) and (17), it can be seen that for any adaptive function τ, the designed adaptive law has the following two properties:

[0131]

[0132]

[0133] For example, in designing the controller, define a set of error variables: z2 = x2 - x 2eq , e1 = x1 - x 1d (t),

[0134] where x 1d denotes the desired trajectory, x1 denotes the actual trajectory, and z1 denotes the tracking error. In the control of the system, it is necessary to ensure that z1 approaches 0. Where K is a constant gain greater than 0. Since:

[0135]

[0136] Only need to ensure that z2 is as small as possible and approaches 0, then z1 will also approach 0. Based on the state space expression, the expression of is as follows:

[0137]

[0138] Define the virtual control law α2 of x3 as follows:

[0139] α2 = α 2a + α 2s (22)

[0140] Combining formula (21), we can get:

[0141]

[0142] The designed robust control function α 2s can be represented as:

[0143] α 2s = α 2s1 + α 2s2 (24)

[0144] ​T2= ω2φ2Z2 (25)

[0145] α 2s1 = -k 2s1 z2 (26)

[0146]

[0147]

[0148] where ω2is a positive weight factor, k2is a positive scalar, and C φ2 is a positive definite constant diagonal matrix. Defining z3= x3- α2as the input difference, substituting the expression of the control law part into the expression of α

[0149]

[0150] The robust control function α 2s2 should satisfy the following conditions:

[0151]

[0152] where ε2is a positive design parameter that can be arbitrarily close to zero. Condition 1 indicates that the robust control function α 2s2 is synthesized based on the parameter uncertainty and the uncertain nonlinearities ; and condition 2 is to ensure that α 2s2 is dissipative in nature so that it does not interfere with the function of the adaptive control part α 2s2 .

[0153] Define a semi-positive definite function V2, where ω2is a positive weight factor.

[0154] Substituting into V2, the derivative of V2with respect to time is obtained as:

[0155]

[0156] Next, the actual control law u of the synthesized system is determined. Choose the following Lyapunov function:

[0157]

[0158] From z3= x3- α2, we have:

[0159]

[0160] where

[0161]

[0162]

[0163] According to formula (32) to formula (35), we have:

[0164]

[0165] Thus, the control input is:

[0166]

[0167] where,

[0168]

[0169] where, k 3s1 is a normal number, u s2 is a positive constant diagonal matrix satisfying the following conditions:

[0170]

[0171] In addition, from formula (29), formula (36) and formula (37), we have:

[0172]

[0173] From formula (30), formula (39) and formula (40), we have:

[0174]

[0175] Therefore, z1, z2 and z3 are bounded. As can be seen from the error variable definition part, x 2eq is bounded. From formula (34), we know that, is bounded, so u is bounded. For any adaptive function τ, the boundary of the positive definite function V3 can be judged as:

[0176]

[0177] Therefore, in the controller, as long as reasonable parameters can be selected, the difference between the actual output value of the system and the expected value can be very small.

[0178] Based on this, combined with the prediction model of the throttling coefficient of the hydraulic valve and the mathematical model of the valve controlled cylinder system, an erosion wear compensation model is constructed.

[0179] According to formula (13), we have:

[0180]

[0181] According to formula (11), we have:

[0182]

[0183] By combining formula (9), formula (10) and formula (44), there are:

[0184]

[0185] Let the voltage corresponding to the throttle coefficient before erosion be u0, and the voltage corresponding to the throttle coefficient after erosion be u1. By combining formula (12), formula (43) and formula (45), the compensation voltage du determined by the erosion wear compensation model can be calculated by the following formula (46):

[0186] du=u0-u1 (46)

[0187] The above at least one technical solution adopted by the embodiments of the present disclosure can achieve the following beneficial effects: the erosion rate function of the hydraulic valve is fitted by performing finite element simulation on the fluid domain of the hydraulic valve; the throttle coefficient prediction model of the hydraulic valve is established based on the erosion rate function and the throttle coefficient before erosion; the mathematical model of the hydraulic system is established, and the adaptive law and the controller are designed based on the mathematical model; wherein the hydraulic system includes the hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system; the erosion wear compensation model of the hydraulic system is established based on the throttle coefficient prediction model and the mathematical model; the output voltage of the hydraulic system is adaptively controlled by using the adaptive law, the controller and the erosion wear compensation model, the throttle coefficient prediction model of the hydraulic valve can be established, the mathematical model of the hydraulic system is established and the adaptive law and the controller are designed, and then the erosion wear compensation model of the hydraulic system is established based on the throttle coefficient prediction model and the mathematical model, under the action of the adaptive law and the controller, the output voltage of the hydraulic system is adaptively controlled by using the erosion wear compensation model, so as to improve the control precision of the hydraulic valve and prolong the service life of the hydraulic valve.

[0188] The above mainly introduces the scheme provided by the embodiments of the present disclosure. It can be understood that, in order to realize the above functions, the electronic device contains the hardware structure and / or software module corresponding to each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed in the present text, the present disclosure can be realized in the form of hardware or the combination of hardware and computer software. Whether a certain function is realized by hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present disclosure.

[0189] The embodiments of the present disclosure can divide the functional units of the electronic device according to the above method examples. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The integrated module can be implemented in the form of hardware or in the form of a software functional module. It should be noted that the division of the modules in the embodiments of the present disclosure is illustrative, and is only a logical functional division. When actually implemented, another division manner can be used.

[0190] In the case of dividing each functional module according to each function, the exemplary embodiments of the present disclosure provide an adaptive control device based on erosion wear compensation, which can be an electronic device or a chip applied to an electronic device. Figure 7 A structure diagram of the adaptive control device based on erosion wear compensation provided by the exemplary embodiments of the present disclosure is shown. As shown in Figure 7 The device 700 includes:

[0191] The simulation module 701 is configured to perform finite element simulation on a fluid domain of a hydraulic valve, and fit an erosion rate function of the hydraulic valve.

[0192] The construction module 702 is configured to establish a throttle coefficient prediction model based on the erosion rate function and a throttle coefficient before erosion.

[0193] The construction module 702 is further configured to establish a mathematical model of a hydraulic system, and design an adaptive law and a controller based on the mathematical model. The hydraulic system includes the hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system.

[0194] The construction module 702 is further configured to establish an erosion wear compensation model of the hydraulic system based on the throttle coefficient prediction model and the mathematical model.

[0195] The control module 703 is configured to perform adaptive control on an output voltage of the hydraulic system by using the adaptive law, the controller, and the erosion wear compensation model.

[0196] In some embodiments, the simulation module 701 is further configured to perform finite element simulation on the fluid domain of the hydraulic valve to obtain erosion rates under a plurality of different valve opening degrees and working pressure differences.

[0197] The erosion rates under the plurality of different valve opening degrees and working pressure differences are fitted by using an E / CRC wear model to obtain the erosion rate function of the hydraulic valve.

[0198] In some embodiments, the E / CRC wear model is represented by the following formula:

[0199]

[0200] wherein E R represents the E / CRC wear model, represents the mass flow rate of particles, N a represents the number of particles colliding per unit time, v represents the particle erosion velocity; S(t) represents the erosion wear area per unit time, b(v) represents the velocity index (generally taking the empirical value 2.6), C(d) represents the particle property function, taking the value 1.8x10 -9 , f(θ α ) is the erosion angle function, which takes the value of a piecewise function;

[0201] The erosion rate function is represented by the following formula:

[0202]

[0203] wherein ER represents the erosion rate function, x v represents the valve opening, ΔP represents the working pressure difference, and the fitting degree of the erosion rate function is 0.90865.

[0204] In some embodiments, the construction module 702 is further configured to obtain the valve opening before erosion and the erosion time of the hydraulic valve;

[0205] Based on the valve opening before erosion, the erosion time and the erosion rate function, the valve opening after erosion of the hydraulic valve is calculated.

[0206] Based on the valve opening before erosion, the valve opening after erosion and the throttling coefficient before erosion, a throttling coefficient prediction model of the hydraulic valve is established.

[0207] In some embodiments, the valve opening after erosion is calculated by the following formula:

[0208]

[0209] wherein x v ' represents the valve opening after erosion, x v0 represents the valve opening before erosion, ER represents the erosion rate function, Δt represents the erosion time, and ρ v represents the material density of the valve core and valve sleeve of the hydraulic valve.

[0210] In some embodiments, the throttling coefficient prediction model is represented by the following formula:

[0211]

[0212] wherein C V represents the throttling coefficient after erosion, CV0 The throttling coefficient before the erosion is represented, and other parameters are described above.

[0213] In some embodiments, the control module 703 is further configured to output a current voltage based on the adaptive law and the controller;

[0214] output a compensation voltage based on the erosion wear compensation model, the compensation voltage being related to a current erosion time and a current working condition;

[0215] compensate the current voltage by using the compensation voltage, and the output voltage of the hydraulic system comprises the current voltage and the compensation voltage.

[0216] The electronic device provided by the example embodiments of the present disclosure also includes at least one processor, a memory for storing at least one processor-executable instruction, and wherein the at least one processor is configured to execute the instructions to implement the steps of the above method.

[0217] Figure 8 The structure of the electronic device provided by the example embodiments of the present disclosure is shown. As shown in the figure, the electronic device 800 includes at least one processor 801 and a memory 802 coupled to the processor 801, and the processor 801 can execute the corresponding steps in the above method disclosed by the example embodiments of the present disclosure. Figure 8

[0218] The processor 801 described above can also be referred to as a central processing unit (CPU), which can be an integrated circuit chip with signal processing capability. Each step in the above method disclosed by the example embodiments of the present disclosure can be completed by the integrated logic circuit of hardware or the instructions in the form of software in the processor 801. The processor 801 described above can be a general-purpose processor, a digital signal processor (DSP), an ASIC, a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor. The steps of the method disclosed in conjunction with the example embodiments of the present disclosure can be directly embodied as a hardware coding processor to execute, or a combination of hardware and software modules in the coding processor to execute. The software module can be located in the memory 802, such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, a register, or other mature storage medium in the art. The processor 801 reads the information in the memory 802 and completes the steps of the above method in combination with the hardware thereof. ​

[0219] In addition, when various operations / processes according to the present disclosure are implemented by software and / or firmware, they can be transferred from a storage medium or a network to a computer system having a dedicated hardware structure, for example, Figure 9 The computer system 900 shown is installed with the programs constituting the software. When the various programs are installed, the computer system can perform various functions, including the functions described above. Figure 9 A schematic diagram of the structure of a computer system provided by an exemplary embodiment of the present disclosure is shown.

[0220] Computer system 900 is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic devices can also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0221] like Figure 9 As shown, the computer system 900 includes a computing unit 901, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 902 or a computer program loaded from a storage unit 908 into a random access memory (RAM) 903. Various programs and data required for the operation of the computer system 900 can also be stored in the RAM 903. The computing unit 901, the ROM 902, and the RAM 903 are connected to each other via a bus 904. An input / output (I / O) interface 905 is also connected to the bus 904.

[0222] The plurality of components in the computer system 900 are connected to the I / O interface 905, including: an input unit 906, an output unit 907, a storage unit 908, and a communication unit 909. The input unit 906 can be any type of device capable of inputting information to the computer system 900, which can receive inputted digital or character information, and generate key signal inputs related to user settings and / or function controls of the electronic device. The output unit 907 can be any type of device capable of presenting information, and can include, but is not limited to, a display, a speaker, a video / audio output terminal, a vibrator, and / or a printer. The storage unit 908 can include, but is not limited to, a magnetic disk, an optical disk. The communication unit 909 allows the computer system 900 to exchange information / data with other devices through a network such as the Internet, and can include, but is not limited to, a modem, a network card, an infrared communication device, a wireless communication transceiver, and / or a chipset, for example, a Bluetooth™ device, a WiFi device, a WiMax device, a cellular communication device, and / or the like.

[0223] The computing unit 901 can be various general and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 901 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The computing unit 901 performs various methods and processes described above. For example, in some embodiments, the above-described methods disclosed by embodiments of the present disclosure can be implemented as a computer software program, which is tangibly contained in a machine-readable medium, for example, the storage unit 908. In some embodiments, part or all of the computer program can be loaded and / or installed on the electronic device via the ROM 902 and / or the communication unit 909. In some embodiments, the computing unit 901 can be configured to perform the above-described methods disclosed by embodiments of the present disclosure by any other appropriate means, for example, by means of firmware.

[0224] Embodiments of the present disclosure also provide a computer-readable storage medium, wherein when instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to perform the above-described methods disclosed by embodiments of the present disclosure.

[0225] The computer-readable storage medium in the embodiments of the present disclosure can be a tangible medium that can contain or store a program for use by an instruction execution system, device or equipment or used in combination with an instruction execution system, device or equipment. The above-mentioned computer-readable storage medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the above. More specifically, the above-mentioned computer-readable storage medium can include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0226] The computer-readable medium may be included in the electronic device, or may exist independently without being incorporated into the electronic device.

[0227] The embodiments of the present disclosure further provide a computer program product, including a computer program, wherein when the computer program is executed by a processor, the method disclosed in the embodiments of the present disclosure is implemented.

[0228] In embodiments of the present disclosure, computer program code for performing the operations of the present disclosure may be written in one or more programming languages ​​or combinations thereof, including but not limited to object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer.

[0229] The flow diagrams and the block diagrams in the drawings are illustrations of architectures, functionalities, and operations of possible implementations of systems, methods, and computer program products according to various embodiments of present disclosure. In this regard, each block in the flow diagrams or block diagrams can represent a module, a segment, or a portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that in some alternative implementations, the functions noted in the block can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and / or flow diagrams, and combinations thereof, can be implemented by special purpose hardware-based systems that perform the specified functions or operations, or combinations of special purpose hardware and computer instructions.

[0230] The modules, components or units described in the embodiments of the present disclosure can be implemented by software or by hardware. In some cases, the name of the module, component or unit does not constitute a limitation on the module, component or unit itself.

[0231] The functions described above in the specification of the present disclosure can be performed by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs), Application-specific Integrated Circuits (ASICs), Application-specific Standard Products (ASSPs), System-on-a-chip systems (SOCs), Complex Programmable Logic Devices (CPLDs), etc.

[0232] The above description is merely some embodiments of the present disclosure and a description of principles of technology used. It should be understood by those skilled in the art that the disclosed scope of the present disclosure is not limited to the technical solutions formed by the specific combinations of the above technical features, and also covers other technical solutions formed by the combinations of the above technical features or equivalent features without departing from the above disclosed concept. For example, the technical solutions formed by the mutual replacement of the above features and the technical features disclosed in the present disclosure (but not limited to) having similar functions.

[0233] Although some specific embodiments of the present disclosure have been described in detail by way of examples, it should be understood that modifications can be made to the above embodiments without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. An adaptive control method based on erosion wear compensation, characterized in that: include: Performing finite element simulation on the fluid domain of the hydraulic valve to obtain an erosion rate function of the hydraulic valve by fitting; Establishing a throttling coefficient prediction model for the hydraulic valve based on the erosion rate function and the throttling coefficient before erosion; Establishing a mathematical model of a hydraulic system, and designing an adaptive law and a controller based on the mathematical model; wherein the hydraulic system includes the hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system; Establishing an erosion wear compensation model for the hydraulic system based on the throttling coefficient prediction model and the mathematical model; Adaptively controlling the output voltage of the hydraulic system using the adaptive law, the controller, and the erosion wear compensation model; The step of establishing a throttling coefficient prediction model for the hydraulic valve based on the erosion rate function and the throttling coefficient before erosion includes: Obtaining the valve opening and erosion time of the hydraulic valve before erosion; Calculating the valve port opening of the hydraulic valve after erosion based on the valve port opening before erosion, the erosion time, and the erosion rate function; Establishing a throttling coefficient prediction model for the hydraulic valve based on the valve port opening before erosion, the valve port opening after erosion, and the throttling coefficient before erosion; The valve opening after erosion is calculated by the following formula: ， in, x v ’ Indicates the valve opening after erosion, x v0 Indicates the valve opening before erosion, ER represents the erosion rate function, Indicates the erosion time, Indicates the material density of the valve core and valve sleeve of the hydraulic valve; The throttling coefficient prediction model is expressed by the following formula: ， in, C V represents the throttling coefficient after erosion, C V0 Indicates the throttling coefficient before erosion; The adaptive control of the output voltage of the hydraulic system by using the adaptive law, the controller and the erosion wear compensation model includes: outputting a current voltage based on the adaptive law and the controller; Based on the erosion wear compensation model, a compensation voltage is output. The compensation voltage is related to the current erosion time and the current working condition. Under given time and working conditions, the voltage corresponding to the throttling coefficient before erosion is , the voltage corresponding to the throttling coefficient after erosion is , the compensation voltage determined by the erosion wear compensation model for ; The current voltage is compensated by using the compensation voltage, and the output voltage of the hydraulic system includes the current voltage and the compensation voltage.

2. The method according to claim 1, characterized in that The finite element simulation is performed on the fluid domain of the hydraulic valve to obtain the erosion rate function of the hydraulic valve by fitting, including: Finite element simulation of the fluid domain of the hydraulic valve was performed to obtain the erosion rate under different valve openings and working pressure differences; The E / CRC wear model is used to fit the erosion rates under the multiple different valve port openings and working pressure differences to obtain the erosion rate function of the hydraulic valve.

3. The method according to claim 2, characterized in that The E / CRC wear model is expressed by the following formula: ， in, E R represents the E / CRC wear model, represents the mass flow rate of particles, N a represents the number of particles colliding per unit time, v Indicates the particle erosion rate; S ( t ) represents the erosion wear area per unit time, b ( v ) represents the speed index, C ( d ) represents the particle property function, and its value is , f ( θ α ) is the erosion angle function, and its value is a piecewise function; The erosion rate function is expressed by the following formula: in, ER represents the erosion rate function, x v Indicates valve opening, represents the working pressure difference, and the fitting degree of the erosion rate function is 0.90865.

4. An adaptive control device based on erosion wear compensation, characterized in that: include: A simulation module, configured to perform finite element simulation on a fluid domain of a hydraulic valve and obtain an erosion rate function of the hydraulic valve by fitting; A construction module, configured to establish a throttling coefficient prediction model for the hydraulic valve based on the erosion rate function and the throttling coefficient before erosion; The building module is further used to establish a mathematical model of the hydraulic system and design an adaptive law and a controller based on the mathematical model; wherein the hydraulic system includes the hydraulic valve, and the mathematical model is used to describe the working principle of the hydraulic system; The building module is further used to establish an erosion wear compensation model for the hydraulic system based on the throttling coefficient prediction model and the mathematical model; a control module, configured to adaptively control the output voltage of the hydraulic system using the adaptive law, the controller, and the erosion wear compensation model; The construction module is further configured to obtain the valve port opening and erosion time of the hydraulic valve before erosion; calculate the valve port opening of the hydraulic valve after erosion based on the valve port opening before erosion, the erosion time, and the erosion rate function; and establish a throttling coefficient prediction model for the hydraulic valve based on the valve port opening before erosion, the valve port opening after erosion, and the throttling coefficient before erosion; The valve opening after erosion is calculated by the following formula: ， in, x v ’ Indicates the valve opening after erosion, x v0 Indicates the valve opening before erosion, ER represents the erosion rate function, Indicates the erosion time, Indicates the material density of the valve core and valve sleeve of the hydraulic valve; The throttling coefficient prediction model is expressed by the following formula: ， in, C V represents the throttling coefficient after erosion, C V0 Indicates the throttling coefficient before erosion; The control module is further configured to output a current voltage based on the adaptive law and the controller; output a compensation voltage based on the erosion wear compensation model, wherein the compensation voltage is related to the current erosion time and the current working condition; under a given time and working condition, the voltage corresponding to the throttling coefficient before erosion is , the voltage corresponding to the throttling coefficient after erosion is , the compensation voltage determined by the erosion wear compensation model for ; The current voltage is compensated by the compensation voltage, and the output voltage of the hydraulic system includes the current voltage and the compensation voltage.

5. An electronic device, characterized in that: include: at least one processor; a memory for storing the at least one processor-executable instruction; The at least one processor is configured to execute the instructions to implement the steps of the method according to any one of claims 1 to 3.

6. A computer-readable storage medium, characterized in that When the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to perform the steps of the method according to any one of claims 1 to 3.

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