A fractional-order sliding mode composite control method for multi-temperature zone structural thermal test system

Abstract

The present invention discloses a fractional-order sliding mode composite control method for a multi-temperature zone structural thermal test system, which relates to the field of complex environment simulation in aerospace. The fractional-order sliding mode composite control method for a multi-temperature zone structural thermal test system includes establishing a multi-temperature zone heat transfer model for a structural thermal test; converting the multi-temperature zone heat transfer model for a structural thermal test into a first-order control model; using the multi-temperature zone structural thermal test system error, the fractional-order multi-temperature zone structural thermal test system error power function integral term and differential term to construct a fractional-order sliding mode surface for a multi-temperature zone structural thermal test system; establishing a terminal sliding mode fast reaching law; based on the first-order control model, introducing a delay observer, thereby establishing a fractional-order sliding mode composite controller for a multi-temperature zone structural thermal test system. The method of the present invention solves the problem that the existing multi-temperature zone structural thermal test system has multiple disturbances that cause low control accuracy, and realizes the limitation of all concentrated disturbances.

Description

Technical Field

[0001] The invention relates to the technical field of complex environment simulation in aerospace, and in particular to a fractional-order sliding mode composite control method for a multi-temperature zone structural thermal test system. Background Art

[0002] Hypersonic aircraft have attracted much attention from all countries due to their ultra-high flight speed. In the development process of hypersonic aircraft, the safety of its thermal protection system design must be fully considered, and structural thermal testing is an important way to test the quality of hypersonic aircraft thermal protection design. Therefore, how to achieve accurate simulation of multi-temperature zone structural thermal test system is crucial.

[0003] The multi-temperature zone structural thermal test system is highly nonlinear and coupled, with unmodeled dynamics, parameter uncertainty, etc. The traditional PID controller cannot solve the problem of low tracking accuracy under nonlinear disturbances and uncertain conditions, and cannot eliminate the system oscillation problem of the unmodeled part. Summary of the invention

[0004] In view of the above problems existing in the prior art, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is how to solve the influence of nonlinear disturbances, uncertainties and system oscillations of the unmodeled parts on the control accuracy in the multi-temperature zone structural thermal test system, and solve the problem of low tracking accuracy of the traditional PID controller.

[0006] To solve the above technical problems, the present invention provides the following technical solutions: a fractional-order sliding mode composite control method for a multi-temperature zone structural thermal test system, which includes, based on the law of conservation of energy, establishing a multi-temperature zone heat transfer model for the structural thermal test and dividing heat conduction, heat convection and heat radiation according to the time history; defining system input variables and system output variables and introducing the output variable diagonal matrix and all concentrated disturbances to convert the multi-temperature zone heat transfer model for the structural thermal test into a first-order control model; defining the multi-temperature zone structural thermal test system error, and using the multi-temperature zone structural thermal test system error, the fractional-order multi-temperature zone structural thermal test system error power function integral term and differential term to construct a fractional-order sliding mode surface for the multi-temperature zone structural thermal test system; using the constant speed reaching law and the power reaching law to establish a terminal sliding mode fast reaching law; based on the first-order control model, introducing a delay observer to suppress all the concentrated disturbances, thereby establishing a fractional-order sliding mode composite controller for the multi-temperature zone structural thermal test system.

[0007] As an optimal scheme of the fractional-order sliding mode composite control method of the multi-temperature zone structural thermal test system described in the present invention, the multi-temperature zone structural thermal test system includes a non-contact radiation heater, an electric power regulation device, a calorimetric sensor, and a temperature transmitter, wherein the non-contact radiation heater is a linear iodine tungsten filament quartz lamp group.

[0008] As a preferred solution of the fractional-order sliding mode composite control method of the multi-temperature zone structural thermal test system of the present invention, wherein: the linear iodine-tungsten filament quartz lamp groups transfer part of the electric energy input by the linear iodine-tungsten filament quartz lamp groups to the h test piece groups to be tested in the form of heat convection and heat radiation; based on the law of conservation of energy, the multi-temperature zone heat transfer model of the structural thermal test is:

[0009] ,

[0010] ,

[0011] ,

[0012] in, is the input power matrix of the linear tungsten iodine filament quartz lamp group at time t; is the internal energy matrix of the linear iodine-tungsten filament quartz lamp set itself at time t; is a matrix of thermal radiation coupling factors outputted outward by the linear iodine-tungsten filament quartz lamp groups; is the thermal radiation energy matrix outputted outward by ƒ linear iodine-tungsten filament quartz lamp groups at time t; is a matrix of heat convection coupling factors outputted outward by the linear iodine-tungsten filament quartz lamp groups; is the heat convection energy matrix outputted outward by the linear iodine-tungsten filament quartz lamp groups at time t; is the coupling factor matrix of energy loss of the linear iodine-tungsten filament quartz lamp group; is the energy matrix of heat loss of ƒ linear tungsten iodine filament quartz lamp groups at time t; is the heat conduction energy matrix outputted outward by ƒ linear iodine-tungsten filament quartz lamp groups at time t; is the thermal energy matrix of the filament resistance of the linear tungsten iodine filament quartz lamp group at time t; is the thermal expansion acoustic energy matrix of the linear iodine tungsten filament quartz lamp group at time t; is the absorption factor matrix of the thermal radiation coupling output by the linear tungsten-iodine filament quartz lamp groups ƒ and the test piece groups to be tested h; is the absorption factor matrix of the output heat convection coupling between the ƒ linear iodine-tungsten filament quartz lamp groups and the h test piece groups to be tested; is the internal energy matrix of the h test pieces to be tested at time t; is the thermal radiation coupling factor matrix outputted to the outside by the h test pieces; is the thermal radiation energy matrix outputted outward by the h test pieces at time t; is the thermal convection coupling factor matrix outputted to the outside by the h test pieces; is the thermal convection energy matrix output by the h test pieces at time t; is the coupling factor matrix of other additional loss energy outputted to the outside by the h test pieces to be tested; is the additional loss energy matrix output by the h test pieces to be tested at time t.

[0013] As a preferred solution of the fractional-order sliding mode composite control method of the multi-temperature zone structural thermal test system of the present invention, the system input variable is:

[0014] U ( t ) = [ U 1 2 ( t ) U 2 2 ( t ) ⋅⋅⋅ U f 2 ( t ) ] T ,

[0015] in, is the square of the input voltage of the linear tungsten iodine filament quartz lamp group at time t.

[0016] As a preferred solution of the fractional-order sliding mode composite control method of the multi-temperature zone structural thermal test system of the present invention, the output variable of the system is:

[0017] T test ( t ) = [ T t 1 ( t ) T t 2 ( t ) ⋅⋅⋅ T th ( t ) ] T ,

[0018] in, For in time At , the temperature of the h hypersonic vehicle test pieces to be tested.

[0019] As a preferred solution of the fractional-order sliding mode composite control method of the multi-temperature zone structure thermal test system of the present invention, the input power matrix of the linear iodine tungsten filament quartz lamp group is:

[0020] Q e ( t ) = [ Q e 1 ( t ) Q e 2 ( t ) ⋮ Q ef ( t ) ] = [ U 1 2 ( t ) R 1 t U 2 2 ( t ) R 2 t ⋯ U f 2 ( t ) R f t ] T ,

[0021] Among them, R ƒ is the filament resistance of the linear iodine-tungsten filament quartz lamp, satisfying: R 1 =R 2 =…=R ƒ ;

[0022] The internal energy matrix of the h test pieces to be tested is:

[0023] Q ( t ) = [ Q ti 1 ( t ) Q ti 2 ( t ) ⋮ Q tih ( t ) ] = diag ( c tn m tn )( T test ( t ) − T 0 ( t )) ,

[0024] T 0 ( t ) = [ T 0 T 0 ⋯ T 0 ] T ,

[0025] in, is a diagonal matrix; c tn is the specific heat capacity of the material of the nth test piece to be tested; m tn is the mass of the material of the nth test piece to be tested; 1≤n≤h, and n is an integer;

[0026] Then the first-order control model is:

[0027] ,

[0028] ,

[0029] in, for The first order differential of is the output variable diagonal matrix; For all the said concentrated disturbances.

[0030] As a preferred solution of the fractional-order sliding mode composite control method of the multi-temperature zone structure thermal test system of the present invention, the error of the multi-temperature zone structure thermal test system is:

[0031] ,

[0032] in, is the target temperature of the h hypersonic vehicle test pieces to be tested;

[0033] The fractional-order sliding surface of the multi-temperature zone structural thermal test system is:

[0034] ,

[0035] in, is the integral term of the power function of the fractional-order multi-temperature-zone structure thermal test system error; is the differential term of the error power function of the fractional-order multi-temperature zone structure thermal test system; , , , , , is the parameter adjustment gain, which is a positive number; is a symbolic function.

[0036] As a preferred solution of the fractional-order sliding mode composite control method of the multi-temperature zone structural thermal test system of the present invention, the terminal sliding mode fast reaching law is:

[0037] ,

[0038] in, , , is the diagonal matrix gain; is the isokinetic approach law; is the power reaching law.

[0039] As a preferred solution of the fractional-order sliding mode composite control method of the multi-temperature zone structure thermal test system of the present invention, the delay observer is:

[0040] ,

[0041] in, For the previous moment Input variable values ​​of multi-temperature zone structural thermal test system; For the previous moment The first-order differential value of the output variable of the multi-temperature zone structural thermal test system; It was the moment before All concentrated disturbance values ​​of the multi-temperature zone structural thermal test system; yes The estimated value of .

[0042] As a preferred solution of the fractional-order sliding mode composite control method of the multi-temperature zone structure thermal test system of the present invention, wherein: the fractional-order sliding mode composite controller of the multi-temperature zone structure thermal test system is:

[0043] .

[0044] The beneficial effects of the present invention are as follows: the fractional-order sliding mode composite control method for the multi-temperature zone structural thermal test system provided by the present invention solves the problem of low control accuracy caused by multiple disturbances in the existing multi-temperature zone structural thermal test system, and realizes the limitation of all concentrated disturbances. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0046] Figure 1 This is a flow chart of the fractional-order sliding mode composite control method for the multi-temperature zone structural thermal test system described in Example 1 of the present invention.

[0047] Figure 2 It is a two-dimensional dimension diagram of the wing of the aerospace plane hypersonic aircraft described in Example 2 of the present invention and a schematic diagram of its temperature zone division.

[0048] Figure 3 The figure is a schematic diagram of the aero-thermal finite element analysis results and flow trajectory of the wing of the space plane hypersonic aircraft described in Example 2 of the present invention.

[0049] Figure 4 This is a front view of the layout of the quartz lamp group on the wing surface of the aerospace plane hypersonic aircraft described in Example 2 of the present invention.

[0050] Figure 5 This is a curve chart of tracking simulation results of the control method (method 1) of the present invention, which takes temperature zone 1 as the target in embodiment 2 of the present invention.

[0051] Figure 6 This is a curve chart of tracking simulation results of the control method (method 1) of the present invention, which takes temperature zone 2 as the target in embodiment 2 of the present invention.

[0052] Figure 7 This is a tracking error curve diagram of the control method (method 1) of the present invention in embodiment 2 of the present invention with temperature zone 1 as the target.

[0053] Figure 8 This is a tracking error curve diagram of the control method (method 1) of the present invention in Example 2 of the present invention with temperature zone 2 as the target.

[0054] Fig. 9 This is a curve chart of tracking simulation results of using the traditional PID control method (method 2) with temperature zone 1 as the target in embodiment 2 of the present invention.

[0055] Fig.10 This is a curve chart of tracking simulation results of using the traditional PID control method (method 2) with temperature zone 2 as the target in embodiment 2 of the present invention.

[0056] Fig.11 This is a tracking error curve diagram of the traditional PID control method (method 2) in embodiment 2 of the present invention with temperature zone 1 as the target.

[0057] Fig.12 This is a tracking error curve diagram of the traditional PID control method (method 2) in embodiment 2 of the present invention with temperature zone 2 as the target. DETAILED DESCRIPTION

[0058] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0059] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0060] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it an embodiment that is mutually exclusive with other embodiments, either individually or selectively.

[0061] Example 1, reference Figure 1 , which is the first embodiment of the present invention, and provides a fractional-order sliding mode composite control method for a multi-temperature zone structural thermal test system.

[0062] First, the devices included in the multi-temperature zone structural thermal test system include non-contact radiation heaters, electric power regulators, calorimetric sensors, and temperature transmitters.

[0063] The non-contact radiation heater uses a linear iodine tungsten filament quartz lamp group, the electric power regulation device uses a thyristor rectifier, the calorimetric sensor uses a K-type thermocouple with a nickel-based high-temperature alloy probe, and the temperature transmitter uses a thermocouple input isolation safety barrier.

[0064] The fractional-order sliding mode composite control method for multi-temperature zone structural thermal test system includes:

[0065] S1: Based on the law of conservation of energy, a multi-temperature zone heat transfer model for structural thermal tests is established and heat conduction, heat convection and heat radiation are divided according to the time history.

[0066] First, it should be noted that the non-contact radiation heater, i.e., the linear iodine tungsten filament quartz lamp group, transfers part of its input electrical energy to the test piece group to be tested by means of thermal convection and thermal radiation. In this embodiment, the test piece group to be tested is the wing of a hypersonic aircraft.

[0067] Preferably, when the linear iodine-tungsten filament quartz lamp groups transfer part of the electric energy input by the linear iodine-tungsten filament quartz lamp groups to the h test piece groups to be tested by means of heat convection and heat radiation, based on the law of conservation of energy, the multi-temperature zone heat transfer model of the structural thermal test is:

[0068] ,

[0069] ,

[0070] ,

[0071] in, is the input power matrix of a linear iodine-tungsten filament quartz lamp group at time t;

[0072] is the internal energy matrix of a linear iodine-tungsten filament quartz lamp group at time t;

[0073] is the thermal radiation coupling factor matrix outputted by a linear iodine-tungsten filament quartz lamp group;

[0074] is the thermal radiation energy matrix output by a linear iodine-tungsten filament quartz lamp group at time t;

[0075] is the heat convection coupling factor matrix outputted by a linear iodine-tungsten filament quartz lamp group;

[0076] is the heat convection energy matrix output by a linear iodine-tungsten filament quartz lamp group at time t;

[0077] is the coupling factor matrix of energy loss of a linear iodine-tungsten filament quartz lamp group;

[0078] is the energy matrix of heat loss of a linear iodine-tungsten filament quartz lamp group at time t;

[0079] is the heat conduction energy matrix output by a linear iodine-tungsten filament quartz lamp group at time t;

[0080] is the thermal energy matrix of the filament resistance of a linear iodine-tungsten quartz lamp group at time t;

[0081] is the thermal expansion acoustic energy matrix of a linear iodine-tungsten filament quartz lamp group at time t;

[0082] is the absorption factor matrix of the thermal radiation coupling output by ƒ linear iodine-tungsten filament quartz lamp groups and h test pieces to be tested;

[0083] is the absorption factor matrix of the output heat convection coupling between ƒ linear iodine-tungsten filament quartz lamp groups and h test pieces to be tested;

[0084] is the internal energy matrix of the h test pieces to be tested at time t;

[0085] is the thermal radiation coupling factor matrix outputted to the outside by the h test pieces;

[0086] is the thermal radiation energy matrix outputted outward by the h test pieces at time t;

[0087] is the thermal convection coupling factor matrix outputted to the outside by the h test pieces;

[0088] is the thermal convection energy matrix output by the h test pieces at time t;

[0089] is the coupling factor matrix of other additional loss energy outputted to the outside by the h test pieces to be tested;

[0090] is the additional loss energy matrix output by the h test pieces to be tested at time t.

[0091] S2: Define system input variables and system output variables and introduce the output variable diagonal matrix and all concentrated disturbances to transform the multi-temperature zone heat transfer model of the structural thermal test into a first-order control model.

[0092] Specifically, define the system input variables as:

[0093] U ( t ) = [ U 1 2 ( t ) U 2 2 ( t ) ⋅⋅⋅ U f 2 ( t ) ] T ,

[0094] in, is the square of the input voltage of the linear tungsten iodine filament quartz lamp group at time t.

[0095] The system output variables are:

[0096] T test ( t ) = [ T t 1 ( t ) T t 2 ( t ) ⋅⋅⋅ T th ( t ) ] T ,

[0097] in, For in time At , the temperature of the h hypersonic vehicle test pieces to be tested.

[0098] The input power matrix of another linear iodine tungsten filament quartz lamp group is:

[0099] Q e ( t ) = [ Q e 1 ( t ) Q e 2 ( t ) ⋮ Q ef ( t ) ] = [ U 1 2 ( t ) R 1 t U 2 2 ( t ) R 2 t ⋯ U f 2 ( t ) R f t ] T ,

[0100] Among them, R ƒ is the filament resistance of the linear iodine tungsten filament quartz lamp, satisfying: R 1 =R 2 =…=R ƒ ;

[0101] The internal energy matrix of the h test pieces to be tested is:

[0102] Q ( t ) = [ Q ti 1 ( t ) Q ti 2 ( t ) ⋮ Q tih ( t ) ] = diag ( c tn m tn )( T test ( t ) − T 0 ( t )) ,

[0103] T 0 ( t ) = [ T 0 T 0 ⋯ T 0 ] T ,

[0104] in, is a diagonal matrix;

[0105] c tn is the specific heat capacity of the material of the nth test piece to be tested;

[0106] m tn is the mass of the material of the nth test piece to be tested;

[0107] 1≤n≤h, and n is an integer;

[0108] Then the first-order control model is:

[0109] ,

[0110] ,

[0111] in, for The first order differential of

[0112] is the diagonal matrix of output variables;

[0113] for all concentrated disturbances.

[0114] S3: Define the multi-temperature zone structure thermal test system error, and construct the fractional-order sliding surface of the multi-temperature zone structure thermal test system by using the multi-temperature zone structure thermal test system error, the fractional-order multi-temperature zone structure thermal test system error power function integral term and the differential term.

[0115] Specifically, the multi-temperature zone structure thermal test system error is defined as:

[0116] ,

[0117] in, is the target temperature of the h hypersonic vehicle test pieces to be tested;

[0118] Therefore, the fractional-order sliding surface of the multi-temperature zone structural thermal test system is:

[0119] ,

[0120] in, is the integral term of the power function of the fractional-order multi-temperature zone structure thermal test system error;

[0121] is the differential term of the power function of the fractional-order multi-temperature zone structure thermal test system error;

[0122] , , , , , is the parameter adjustment gain, which is a positive number;

[0123] is a symbolic function.

[0124] S4: Using the constant speed approaching law and the power approaching law, establish the terminal sliding mode rapid approaching law.

[0125] Specifically, the terminal sliding mode fast approaching law is:

[0126] ,

[0127] in, , , is the diagonal matrix gain;

[0128] is the isokinetic approach law;

[0129] is the power reaching law.

[0130] S5: Based on the first-order control model, a time-delay observer is introduced to suppress all the centralized disturbances, thereby establishing a fractional-order sliding mode composite controller for the multi-temperature zone structural thermal test system.

[0131] Specifically, the delay observer is:

[0132] ,

[0133] in, For the previous moment Input variable values ​​of multi-temperature zone structural thermal test system;

[0134] For the previous moment The first-order differential value of the output variable of the multi-temperature zone structural thermal test system;

[0135] It was the moment before All concentrated disturbance values ​​of the multi-temperature zone structural thermal test system;

[0136] yes The estimated value of .

[0137] Then the fractional-order sliding mode composite controller of the multi-temperature zone structural thermal test system is constructed as follows:

[0138] .

[0139] Furthermore, the stability of the fractional-order sliding mode composite controller for constructing a multi-temperature zone structural thermal test system is proved:

[0140] The first-order differential of the multi-temperature zone structure thermal test system error is:

[0141] ,

[0142] The first-order differential of the fractional sliding surface of the multi-temperature zone structural thermal test system is:

[0143] ,

[0144] Substituting the first-order differential of the error of the multi-temperature zone structure thermal test system and the fast reaching law of the terminal sliding mode into the first-order differential of the fractional sliding mode surface of the multi-temperature zone structure thermal test system, we get:

[0145] ,

[0146] Further, the fractional-order sliding mode composite controller of the multi-temperature zone structural thermal test system is substituted into the first-order control model to obtain the observation error equation:

[0147] ,

[0148] in, is the observation error.

[0149] Define the Lyapunov equation as: .

[0150] Take the first-order differential of the Lyapunov equation and substitute it into the first-order differential of the fractional sliding surface and the observation error equation of the multi-temperature zone structural thermal test system:

[0151] ,

[0152] Further transposing the terms gives:

[0153] ,

[0154] in,

[0155] ,

[0156] ,

[0157] Further, according to the Lyapunov equation: , calculated:

[0158] ,

[0159] Among them, satisfy and Both are greater than 0.

[0160] The time it takes for the system to converge to the sliding surface is:

[0161] ,

[0162] According to the above formula, the convergence condition is:

[0163] ,

[0164] ,

[0165] Further:

[0166] ,

[0167] ,

[0168] The system state can converge to a neighborhood of the sliding surface as .

[0169] In summary, the control method proposed in the present invention first establishes a multi-temperature zone heat transfer model of a hypersonic aircraft structure thermal test dominated by the Stefan Boltzmann law, including heat conduction, heat convection and heat radiation; secondly, based on the definition of input variables and output variables, a first-order control model of the multi-temperature zone heat transfer model of a hypersonic aircraft structure thermal test is established, including the output variable diagonal matrix and all concentrated disturbances; thirdly, based on the definition of system errors, a fractional-order sliding surface of a multi-temperature zone structure thermal test system is established, including the fractional-order multi-temperature zone structure thermal test system error power function integral term and differential term; finally, a terminal sliding mode fast reaching law is established, including the constant speed reaching law and the power reaching law, so as to comprehensively construct a fractional-order sliding mode composite controller of a multi-temperature zone structure thermal test system to suppress all concentrated disturbances. The problem of low control accuracy caused by multiple disturbances in the existing multi-temperature zone structure thermal test system is solved.

[0170] Example 2, reference Figure 2 to Figure 12 , which is the second embodiment of the present invention, and this embodiment is based on the previous embodiment. Different from the previous embodiment, this embodiment provides a simulation verification test of a fractional-order sliding mode composite control method for a multi-temperature zone structural thermal test system.

[0171] In order to verify and illustrate the technical effects of the present invention, the wing of a space plane hypersonic aircraft is selected as the test target in this embodiment to test the control method proposed in the present invention. The test results are compared by scientific demonstration to verify the real effect of the control method.

[0172] Reference Figure 2 , is a two-dimensional dimension diagram of the wing of the space plane hypersonic aircraft selected in this embodiment and a schematic diagram of its temperature zone division. Figure 2 As shown in the figure, the specific dimensions of the wing of the space plane hypersonic aircraft are: wing root 3550mm, wingspan 1250mm, leading edge sweep angle 70°, trailing edge sweep angle 15°. The wing of the space plane hypersonic aircraft is placed horizontally, and the midpoint of the wing root is taken to divide the temperature zone 1 and temperature zone 2.

[0173] Reference Figure 3 , which are the aerodynamic thermal finite element analysis results and flow trajectory diagram of the wing of the space plane hypersonic vehicle. Figure 3 As shown in Table 1, the 3D image of the wing of the space plane hypersonic aircraft is imported into SolidWorks, and the FlowSimulation plug-in parameters are set: static pressure 5475Pa, temperature 216.65K, Mach number 7Ma, angle of attack 0.349rad, so as to obtain the finite element analysis results and flow trajectory diagram. The specific results are shown in Table 1.

[0174] Table 1 Aerothermal finite element analysis results of temperature zones 1 and 2

[0175] Serial number Average temperature (unit: K) Temperature Zone 1 1189.2 Temperature Zone 2 1293.2

[0176] Reference Figure 4 , is the main view of the layout of the quartz lamp group on the wing surface of the space plane hypersonic aircraft. Figure 4 As shown, according to the geometric shape characteristics of the wing surface of the aerospace plane hypersonic aircraft, horizontally arranged quartz lamp groups are used, which are: quartz lamp group 1 and quartz lamp group 2 respectively.

[0177] Test environment setting: The multi-temperature zone heat transfer model of the hypersonic aircraft structure thermal test is run on the simulation platform, and temperature zone 1 (1189.2K) and temperature zone 2 (1293.2K) are used as tracking targets. The control method of the present invention (method 1) and the traditional PID control method (method 2) are used for comparative testing, and the test results are obtained. The automated test equipment is turned on and the simulation test of the theoretical model is implemented using MATLB software programming. Simulation data is obtained according to the experimental results. Two groups of data are tested, and each group of data is sampled for 10s. The input temperature of each group of data is calculated and compared with the expected target temperature of the simulation input.

[0178] Test parameter settings: ; ; ; ; ; ; ; ; ; ; ; ; ;.

[0179] In addition, the traditional PID controller is selected for comparison. The traditional PID controller is:

[0180] ,

[0181] Among them, the proportion ;integral ;differential .

[0182] According to the above test environment settings and test parameter settings, refer to Figures 5 to 12 , which is the simulation result of tracking dual-temperature zone targets of the control method of the present invention (method 1) and the traditional PID control method (method 2).

[0183] Specifically, Figure 5 and Figure 6 As shown, the temperature tracking curve of the control method (method 1) of the present invention is consistent with the finite element simulation curve throughout the whole process, which can prove that the control method (method 1) of the present invention can effectively track the target of temperature zone 1 and the target of temperature zone 2 respectively.

[0184] In addition, if Figure 7 and Figure 8 As shown, the control method of the present invention (method 1) has a smaller tracking error, and the tracking error is below 10K throughout the whole process.

[0185] As a comparison, Fig. 9 and Fig.10 As shown in the figure, the temperature tracking curve of the traditional PID control method (method 2) gradually fits the finite element simulation curve only after the running time reaches 80s.

[0186] In addition, if Fig.11 and Fig.12 As shown in the figure, the traditional PID control method (method 2) has obvious tracking errors at the beginning of the operation. When the operation time is 80s, method 2 can reach the target value.

[0187] In summary, the control method of the present invention transforms the multi-temperature zone heat transfer model into a first-order control model, and combines it with the terminal sliding mode fast reaching law, which can quickly improve the tracking convergence speed and maintain a small error.

[0188] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A fractional-order sliding mode composite control method for a multi-temperature zone structural thermal test system, characterized in that: include, Based on the law of conservation of energy, a multi-temperature zone heat transfer model for structural thermal tests is established and heat conduction, heat convection and heat radiation are divided according to the time history. The system input variables and system output variables are defined and the output variable diagonal matrix and all concentrated disturbances are introduced to transform the multi-temperature zone heat transfer model of the structural thermal test into a first-order control model; Defining a multi-temperature zone structure thermal test system error, and constructing a fractional-order sliding surface of the multi-temperature zone structure thermal test system by using the multi-temperature zone structure thermal test system error, the fractional-order multi-temperature zone structure thermal test system error power function integral term and the differential term; Using the constant speed approaching law and the power approaching law, the terminal sliding mode fast approaching law is established; Based on the first-order control model, a time-delay observer is introduced to suppress all the centralized disturbances, thereby establishing a fractional-order sliding mode composite controller for a multi-temperature zone structural thermal test system; The multi-temperature zone structural thermal test system comprises a non-contact radiation heater, an electric power regulating device, a calorimetric sensor, and a temperature transmitter, wherein the non-contact radiation heater is a linear iodine tungsten filament quartz lamp group; The system output variables are: T test (t)=[T t1 (t)T t2 (t)···T th (t)] T Among them, T test (t)∈R h×1 is the temperature of the group of h hypersonic vehicle test pieces to be tested at time t; The system output variables are: T test (t)=[T t1 (t)T t2 (t)···T th (t)] T Among them, T test (t)∈R h×1 is the temperature of the group of h hypersonic vehicle test pieces to be tested at time t; The input power matrix of the f linear iodine tungsten filament quartz lamp groups is: Among them, R f is the filament resistance of the linear iodine-tungsten filament quartz lamp, satisfying: R1=R2=…=R f ; The internal energy matrix of the h test pieces to be tested is: T0(t)=[T0 T0 … T0] T Among them, diag(c tn m tn )∈R h×h is a diagonal matrix; c tn is the specific heat capacity of the material of the nth test piece to be tested; m tn is the mass of the material of the nth test piece to be tested; 1≤n≤h, and n is an integer; Then the first-order control model is: in, T test The first differential of (t); is the diagonal matrix of the output variables; d(t)∈R f×1 for all said concentrated disturbances; The error of the multi-temperature zone structure thermal test system is: in, is the target temperature of the h hypersonic vehicle test pieces to be tested; The fractional-order sliding surface of the multi-temperature zone structural thermal test system is: in, is the integral term of the power function of the fractional-order multi-temperature-zone structure thermal test system error; is the differential term of the power function of the error of the fractional-order multi-temperature zone structure thermal test system; a1, a2, b1, b2, g1, g2 are parameter adjustment gains, which are positive numbers; sign(e(t)) is the sign function; The terminal sliding mode fast approaching law is: in, L1, L2 are diagonal matrix gains; -L1s∈R h×1 is the isokinetic approach law; is the power reaching law; The delay observer is: Among them, U(t-Δt) is the input variable value of the multi-temperature zone structural thermal test system at the previous time t-Δt; is the first-order differential value of the output variable of the multi-temperature zone structural thermal test system at the previous moment t--Δt; d(t-Δt) is all the concentrated disturbance values ​​of the multi-temperature zone structural thermal test system at the previous moment t-Δt; is the estimated value of d(t); The fractional-order sliding mode composite controller of the multi-temperature zone structural thermal test system is:

2. The fractional-order sliding mode composite control method for a multi-temperature zone structural thermal test system according to claim 1, characterized in that: The f linear iodine-tungsten filament quartz lamp groups transfer part of the electric energy input by the linear iodine-tungsten filament quartz lamp groups to the h test piece groups to be tested in a manner of heat convection and heat radiation; Based on the law of conservation of energy, the multi-temperature zone heat transfer model of the structural thermal test is: Q e (t)=Q i (t)+C r Q r (t)+C cv Q cv (t)+C loss Q loss (t) Q loss (t)=Q cd (t)+Q rt (t)+Q sd (t) αQ r (t)+βQ cv (t)=Q ti (t)+C tr Q tr (t)+C tcv Q tcv (t)+C tloss Q loss (t) Among them, Q e (t)∈R f×1 is the input power matrix of the f linear iodine tungsten filament quartz lamp groups at time t; Q i (t)∈R f×1 is the internal energy matrix of the f linear iodine-tungsten filament quartz lamp groups at time t; C r ∈R f×f is the thermal radiation coupling factor matrix outputted outward by the f linear iodine-tungsten filament quartz lamp groups; Q r (t)∈R f×1 is the thermal radiation energy matrix outputted outward by the f linear iodine tungsten filament quartz lamp groups at time t; C cv ∈R f×f is the heat convection coupling factor matrix outputted outward by the f linear iodine-tungsten filament quartz lamp groups; Q cv (t)∈R f×1 is the heat convection energy matrix outputted outward by the f linear iodine tungsten filament quartz lamp groups at time t; C loss ∈R f×f is the coupling factor matrix of the energy loss of the f linear iodine tungsten filament quartz lamp groups; Q loss (t)∈R f×1 is the energy matrix of heat loss of the f linear iodine tungsten filament quartz lamp groups at time t; Q cd (t)∈R f×1 is the heat conduction energy matrix outputted outward by the f linear iodine-tungsten filament quartz lamp groups at time t; Q rt (t)∈R f×1 is the thermal energy matrix of the filament resistance of the f linear iodine-tungsten filament quartz lamp group at time t; Q sd (t)∈R f×1 is the thermal expansion acoustic energy matrix of the f linear iodine tungsten filament quartz lamp groups at time t; α∈R h×f is the absorption factor matrix of the thermal radiation coupling output by the f linear iodine-tungsten filament quartz lamp groups and the h test pieces to be tested; β∈R h×f is the absorption factor matrix of the heat convection coupling output by the f linear iodine-tungsten filament quartz lamp groups and the h test piece groups to be tested; Q ti (t)∈R h×1 is the internal energy matrix of the h test pieces to be tested at time t; C tr ∈R h×h is the thermal radiation coupling factor matrix outputted to the outside by the h test pieces; Q tr (t)∈R h×1 is the thermal radiation energy matrix output by the h test pieces at time t; C tcv ∈R h×h is the thermal convection coupling factor matrix outputted to the outside by the h test pieces; Q tcv (t)∈R h×1 is the thermal convection energy matrix output by the h test pieces at time t; C tloss ∈R h×h is the coupling factor matrix of other additional loss energy outputted to the outside by the h test pieces to be tested; Q tloss (t)∈R h×1 is the additional loss energy matrix output by the h test pieces to be tested at time t.

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