Automatic accelerator nonlinear control method and device for full-automatic landing of airplane

Abstract

The invention belongs to the field of flight control, and relates to an automatic accelerator nonlinear control method and device for full-automatic landing of an aircraft, and the method comprises the steps: S1, obtaining an accelerator control input quantity; s2, feed-forward lead-lag correction is carried out; s3, negative feedback is superimposed on the correction value, and the accelerator control quantity is formed; s4, automatic accelerator control system transmission calculation is carried out, and the accelerator output quantity is obtained; s5, automatic accelerator execution system transmission calculation is conducted on the accelerator output quantity, and the actuator output quantity is obtained; s6, accelerator system model operation is carried out on the accelerator output quantity to form a first control quantity, and second time delay compensation operation is carried out on the first control quantity to form a second control quantity; and S7, subtracting the second control quantity from the controller output quantity, inputting the controller output quantity into the PD controller, and superposing the first control quantity on the output result to form negative feedback. According to the method, the aircraft approach power compensation effect is improved, and the flight path control precision is improved.

Description

Technical Field

[0001] This application belongs to the field of flight control, and particularly relates to an automatic throttle non-linear control method and device for fully automatic aircraft landing. Background Art

[0002] Fully automatic landing on a mobile platform is an advanced aircraft landing method and the only way to complete aircraft recovery in bad weather such as fog, sandstorm, and heavy snow, which can significantly improve the safety and accuracy of aircraft landing and reduce the workload of pilots.

[0003] The approach power compensation technology is an important part of the fully automatic landing control technology, mainly used to solve the problem of unstable speed during low-speed approach of the aircraft and improve the track control accuracy. The core inner-loop control is the automatic throttle control system. The automatic throttle control system is usually an electro-mechanical control system, and there are non-linear links such as inherent time delay in mechanical transmission (such as cable structure), resulting in system response lag, large overshoot, and long adjustment time, affecting stability. In the method of dealing with mechanical transmission non-linearity, the traditional Smith control method is usually used. As Figure 1 shown, it eliminates the time delay effect by compensating the time delay link, but requires complete model matching. However, in the complex working conditions of approach power compensation, it is difficult to achieve complete model matching, affecting the safety of fully automatic landing. Summary of the Invention

[0004] This application provides an automatic throttle non-linear control method and device for fully automatic aircraft landing, which is improved on the basis of the classical Smith control method to solve the stability problem of the automatic throttle control system under time delay conditions.

[0005] The first aspect of this application provides an automatic throttle non-linear control method for fully automatic aircraft landing, mainly including:

[0006] Step S1: Obtain the throttle control input quantity X(s);

[0007] Step S2: Perform feedforward lead-lag correction on the throttle control input quantity X(s) to obtain the correction value A;

[0008] Step S3: Superimpose a negative feedback Y′(s) including a PD controller on the correction value A to form the throttle control quantity E(s);

[0009] Step S4: Perform automatic throttle control system transfer calculation on the throttle control quantity E(s) to obtain the throttle output quantity U(s);

[0010] Step S5: Perform automatic throttle execution system transfer calculation on the throttle output U(s) to obtain the actuator output Y(s). The automatic throttle execution system includes a throttle system model W p (s) and a first time delay compensation

[0011] Step S6: Perform an operation on the throttle output U(s) using the throttle system model W p (s) to form a first control quantity B1, and perform a second time delay compensation operation on the first control quantity to form a second control quantity B2;

[0012] Step S7: After performing negative feedback of the second control quantity B2 on the controller output Y(s), input it into the PD controller, and superimpose the output result of the PD controller with the first control quantity B1 to form the negative feedback Y′(s).

[0013] Preferably, in step S2, the transfer function used for the feedforward lead-lag correction is where a and T are adjustment parameters, and s is the Laplace operator;

[0014] where the adjustment parameter T is determined by the following formula:

[0015] T = KL / (V ref ·sinθ), where K is the pneumatic correction coefficient, L is the runway length, θ is the glide angle, and V ref is the landing speed;

[0016] The adjustment parameter a is determined by the following formula:

[0017] a = 1.5 + 0.5ΔV / V ref , where ΔV is the real-time airspeed error.

[0018] Preferably, in step S6, the time of the second time delay compensation is obtained by statistically analyzing the mechanical characteristics of multiple aircraft after installation.

[0019] Preferably, in step S7, the time constant T D of the PD controller is determined by simulation;

[0020] Preferably, in step S7, when superimposing the output result of the PD controller with the first control quantity B1, it further includes setting the proportional coefficient Kp of the output result of the PD controller:

[0021] Kp = η·(J / M) 0.5 ;

[0022] Among them, J is the moment of inertia of the engine, M is the mass of the aircraft, η is the damping correction factor, and its value ranges from 0.8 to 1.2.

[0023] The second aspect of this application provides an automatic throttle non-linear control device for fully automatic landing of an aircraft, mainly including:

[0024] An input quantity acquisition module, used to acquire the throttle control input quantity X(s);

[0025] A feedforward lead-lag correction control module, used to perform feedforward lead-lag correction on the throttle control input quantity X(s) to obtain a correction value A;

[0026] A throttle control quantity acquisition module, used to superimpose a negative feedback Y′(s) including a PD controller on the correction value A to form a throttle control quantity E(s);

[0027] An automatic throttle control module, used to perform automatic throttle control system transfer calculation on the throttle control quantity E(s) to obtain a throttle output quantity U(s);

[0028] An automatic throttle execution module, used to perform automatic throttle execution system transfer calculation on the throttle output quantity U(s) to obtain an actuator output quantity Y(s), and the automatic throttle execution system includes a throttle system model W p (s) and a first time delay compensation

[0029] An automatic throttle execution parameter acquisition module, used to perform an operation on the throttle output quantity U(s) with the throttle system model W p [[ID=2,6]](s) to form a first control quantity B1, and perform a second time delay compensation operation on the first control quantity to form a second control quantity B2;

[0030] A PD control module, used to perform negative feedback of the second control quantity B2 on the controller output quantity Y(s), input it into the PD controller, and superimpose the output result of the PD controller on the first control quantity B1 to form the negative feedback Y′(s).

[0031] Preferably, in the feedforward lead-lag correction control module, the transfer function used for the feedforward lead-lag correction is Among them, a and T are adjustment parameters, and s is the Laplace operator;

[0032] Among them, the adjustment parameter T is determined by the following formula:

[0033] T = KL / (V ref ·sinθ), where K is the aerodynamic correction coefficient, L is the runway length, θ is the glide angle, and V ref is the landing speed;

[0034] The adjustment parameter a is determined by the following formula:

[0035] a = 1.5 + 0.5ΔV / V ref , where ΔV is the real-time airspeed error.

[0036] Preferably, in the automatic throttle execution module, the time of the second time delay compensation e -τms is obtained by statistically analyzing the mechanical characteristics of multiple aircraft after installation.

[0037] Preferably, in the PD control module, the time constant T of the PD controller D is determined by simulation.

[0038] Preferably, in the PD control module, when the output result of the PD controller is superimposed on the first control quantity B1, it further includes setting the proportionality coefficient Kp of the output result of the PD controller:

[0039] Kp = η·(J / M) 0.5 ;

[0040] where J is the engine inertia, M is the aircraft mass, and η is the damping correction factor, with a value range of 0.8 to 1.2.

[0041] This application can achieve fast response of the aircraft, enhance the robustness to changes in model parameters, improve the power compensation effect during aircraft approach, and improve the track control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is the schematic diagram of the existing Smith control method.

[0043] Figure 2 is the control schematic diagram of a preferred embodiment of the automatic throttle non-linear control method for fully automatic landing of the aircraft in this application. DETAILED DESCRIPTION OF THE INVENTION

[0044] To make the purpose, technical solutions, and advantages of the implementation of this application clearer, the following will describe the technical solutions in the implementation of this application in more detail in combination with the accompanying drawings in the implementation of this application. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The described implementation is part of the implementations of this application, not all of the implementations. The implementation described below by referring to the accompanying drawings is exemplary and is intended to explain this application and should not be construed as a limitation of this application. Based on the implementations in this application, all other implementations obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of this application. The following will explain the implementation of this application in detail in combination with the accompanying drawings.

[0045] The first aspect of this application provides a method for non-linear control of the automatic throttle for fully automatic aircraft landing, as Figure 2 shown, mainly including:

[0046] Step S1, obtain the throttle control input quantity X(s);

[0047] Step S2, perform feedforward lead-lag correction on the throttle control input quantity X(s) to obtain the correction value A;

[0048] Step S3, superimpose a negative feedback Y′(s) including a PD controller on the correction value A to form the throttle control quantity E(s);

[0049] Step S4, perform transfer calculation of the automatic throttle control system on the throttle control quantity E(s) to obtain the throttle output quantity U(s);

[0050] Step S5, perform transfer calculation of the automatic throttle actuator system on the throttle output quantity U(s) to obtain the actuator output quantity Y(s), and the automatic throttle actuator system includes a throttle system model W p (s) and the first time-delay compensation

[0051] Step S6, perform operation of the throttle system model W p (s) on the throttle output quantity U(s) to form the first control quantity B1, and perform the second time-delay compensation operation on the first control quantity to form the second control quantity B2;

[0052] Step S7, after performing negative feedback of the second control quantity B2 on the controller output quantity Y(s), input it into the PD controller, and superimpose the output result of the PD controller on the first control quantity B1 to form the negative feedback Y′(s).

[0053] Compare Figure 1 andFigure 2 , Figure 1 is the schematic diagram of the existing Smith control method. After the throttle control input X(s) undergoes negative feedback, it first passes through the transfer function of W c (s). W c (s) is the transfer function of the actual automatic throttle controller. The output U(s) is used to drive the automatic throttle execution system, which is a conventional PID controller. Then, it passes through the transfer function of the automatic throttle execution system W p (s)e -τs . Among them, W p (s) is the mathematical model of the actuator, which can be constructed based on the principles of the structures such as the motor, connecting rod, and cable that compose it. e -τs is the time-delay link. After the output U(s) of the automatic throttle controller transfer function passes through W τ (s), it is combined with the output result of the automatic throttle execution system transfer function W p (s)e -τs . They are jointly used as negative feedback and superimposed on the throttle control input X(s). Among them, W τ (s) = (1 - e -τs )W p .

[0054] Based on the Smith control method, this application adds steps such as the transfer of the throttle system model W p (s) and time-delay compensation PD control and feedforward lead-lag correction. First, decompose the existing transfer function of the automatic throttle execution system W p (s)e -τs to obtain the throttle system model W p (s) and the time delay. To distinguish it from the time delay of the traditional Smith control method, refer to Figure 2 , the time delay of the original Smith control method is marked as the first time-delay compensation The newly added time delay in this application is marked as the second time-delay compensation The throttle system model W p (s) and the second time-delay compensation serve as the basis for the control of this scheme. In step S6, they are calculated in parallel with the existing transfer function of the automatic throttle execution system W p (s)e -τs . On this basis, in step S7, a PD controller is introduced to dynamically compensate the error between the theoretical parameters and the actual parameters, and feed it back to the input end in advance to suppress the oscillation caused by time-delay mismatch. Finally, in step S2, a lead-lag correction step is added to offset the amplification effect of PD control on interference, reduce overshoot, and improve the dynamic characteristics of the system.

[0055] In the above manner, the present application can effectively solve problems such as response lag, large overshoot, and long adjustment time caused by the time-delay non-linear link, improve the stability of the system, and further improve the approach power compensation effect and enhance the track control accuracy.

[0056] In some alternative embodiments, in step S2, the transfer function used for the feedforward lead-lag correction is where a and T are adjustment parameters, and s is the Laplace operator; among them, the adjustment parameter T is determined by the following formula:

[0057] T = KL / (V ref ·sinθ), where K is the aerodynamic correction coefficient, L is the runway length, θ is the glide angle, and V ref is the landing speed;

[0058] The adjustment parameter a is determined by the following formula:

[0059] a = 1.5 + 0.5ΔV / V ref , where ΔV is the real-time airspeed error.

[0060] In some alternative embodiments, in step S6, the time of the second time-delay compensation is obtained according to the statistical results of the mechanical characteristics of multiple aircraft after installation, for example, by calculating the average value based on the statistical time-delay results.

[0061] In some alternative embodiments, in step S7, the time constant T of the PD controller D is determined by simulation. In this embodiment, according to the requirements of the automatic throttle response characteristics of full-automatic landing, the time constant T D is determined by simulation and can be adjusted according to the specific characteristics after installation.

[0062] In some alternative embodiments, in the PD control module, when superimposing the output result of the PD controller on the first control quantity B1, it further includes setting the proportional coefficient Kp of the output result of the PD controller:

[0063] Kp = η·(J / M) 0.5 ;

[0064] where J is the engine moment of inertia, M is the aircraft mass, and η is the damping correction factor, with a value range of 0.8 to 1.2.

[0065] This embodiment introduces the optimization of the mass-thrust coupling parameter, improving the environmental adaptability and robustness of the control system. Among them, after increasing the proportional coefficient Kp, the transfer function of the PD controller is Kp(1 + T D s).

[0066] The second aspect of the present application provides an automatic throttle non-linear control device for fully automatic aircraft landing corresponding to the above method, mainly including:

[0067] An input quantity acquisition module, configured to acquire a throttle control input quantity X(s);

[0068] A feed-forward lead-lag correction control module, configured to perform feed-forward lead-lag correction on the throttle control input quantity X(s) to obtain a correction value A;

[0069] A throttle control quantity acquisition module, configured to superimpose a negative feedback Y′(s) including a PD controller on the correction value A to form a throttle control quantity E(s);

[0070] An automatic throttle control module, configured to perform automatic throttle control system transfer calculation on the throttle control quantity E(s) to obtain a throttle output quantity U(s);

[0071] An automatic throttle execution module, configured to perform automatic throttle execution system transfer calculation on the throttle output quantity U(s) to obtain an actuator output quantity Y(s), and the automatic throttle execution system includes a throttle system model W p (s) and a first time-delay compensation

[0072] An automatic throttle execution parameter acquisition module, configured to perform an operation on the throttle output quantity U(s) with the throttle system model W p (s) to form a first control quantity B1, and perform a second time-delay compensation operation on the first control quantity to form a second control quantity B2;

[0073] A PD control module, configured to perform negative feedback of the second control quantity B2 on the controller output quantity Y(s), input it into the PD controller, and superimpose the output result of the PD controller on the first control quantity B1 to form the negative feedback Y′(s).

[0074] In some alternative embodiments, in the feed-forward lead-lag correction control module, the transfer function used for the feed-forward lead-lag correction is where a and T are adjustment parameters, and s is the Laplace operator;

[0075] where the adjustment parameter T is determined by the following formula:

[0076] T = KL / (V ref ·sinθ), where K is an aerodynamic correction coefficient, L is the runway length, θ is the glide angle, and V ref is the landing speed;

[0077] The adjustment parameter a is determined by the following formula:

[0078] a = 1.5 + 0.5ΔV / V ref , where ΔV is the real-time airspeed error.

[0079] In some alternative embodiments, in the automatic throttle execution module, the time of the second time delay compensation is obtained based on the statistics of the mechanical characteristics of multiple aircraft after installation.

[0080] In some alternative embodiments, in the PD control module, the time constant T of the PD controller D is determined by simulation.

[0081] In some alternative embodiments, in the PD control module, when the output result of the PD controller is superimposed on the first control quantity B1, it further includes setting the proportionality coefficient Kp of the output result of the PD controller:

[0082] Kp = η·(J / M) 0.5 ;

[0083] where J is the engine moment of inertia, M is the aircraft mass, and η is the damping correction factor, with a value range of 0.8 to 1.2.

[0084] As described above, the above are only the specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An automatic throttle non-linear control method for fully automatic landing of an aircraft, characterized in that, Including: Step S1: Obtain the throttle control input quantity X(s); Step S2: Perform feedforward lead-lag correction on the throttle control input quantity X(s) to obtain a correction value A; Step S3: Superimpose a negative feedback Y′(s) including a PD controller on the correction value A to form a throttle control quantity E(s); Step S4: Perform automatic throttle control system transfer calculation on the throttle control quantity E(s) to obtain a throttle output quantity U(s); Step S5: Perform automatic throttle execution system transfer calculation on the throttle output U(s) to obtain the actuator output Y(s). The automatic throttle execution system includes a throttle system model W p (s) and a first time-delay compensation Step S6: Perform the operation of the throttle system model W p (s) on the throttle output U(s) to form the first control quantity B1, and perform the second time-delay compensation operation on the first control quantity to form the second control quantity B2; Step S7: After performing negative feedback of the second control quantity B2 on the controller output quantity Y(s), input it into the PD controller, and superimpose the output result of the PD controller on the first control quantity B1 to form the negative feedback Y′(s).

2. The automatic throttle non-linear control method for fully automatic landing of an aircraft according to claim 1, wherein In step S2, the transfer function used for the feedforward lead-lag correction is where a and T are adjustment parameters, and s is the Laplace operator; Wherein, the adjustment parameter T is determined by the following formula: T = KL / (V ref ·sinθ), where K is the aerodynamic correction coefficient, L is the runway length, θ is the glide angle, and V ref is the landing speed; The adjustment parameter a is determined by the following formula: a = 1.5 + 0.5ΔV / V ref , where ΔV is the real-time airspeed error.

3. The automatic throttle non-linear control method for fully automatic aircraft landing according to claim 1, characterized in that, In step S6, the time of the second time delay compensation is obtained according to the statistics of the mechanical characteristics of multiple aircraft after installation.

4. The automatic throttle non-linear control method for fully automatic aircraft landing according to claim 1, characterized in that In step S7, the time constant T of the PD controller D is determined by simulation.

5. The automatic throttle non-linear control method for fully automatic aircraft landing according to claim 1, characterized in that, In step S7, when superimposing the output result of the PD controller on the first control quantity B1, it further includes setting a proportionality coefficient Kp of the output result of the PD controller: Kp = η·(J / M) 0.5 ; Wherein, J is the engine moment of inertia, M is the aircraft mass, and η is a damping correction factor with a value range of 0.8 to 1.

2.

6. An automatic throttle non-linear control device for fully automatic landing of an aircraft, characterized in that, Including: An input quantity acquisition module for obtaining the throttle control input quantity X(s); A feedforward lead-lag correction control module for performing feedforward lead-lag correction on the throttle control input quantity X(s) to obtain a correction value A; A throttle control quantity acquisition module for superimposing a negative feedback Y′(s) including a PD controller on the correction value A to form a throttle control quantity E(s); An automatic throttle control module for performing automatic throttle control system transfer calculation on the throttle control quantity E(s) to obtain a throttle output quantity U(s); An automatic throttle execution module is used to perform automatic throttle execution system transfer calculation on the throttle output U(s) to obtain the actuator output Y(s). The automatic throttle execution system includes a throttle system model W p (s) and a first time-delay compensation An automatic throttle execution parameter acquisition module, which is used to perform an operation on the throttle output U(s) with a throttle system model W p (s) to form a first control quantity B1, and perform a second time delay compensation operation on the first control quantity to form a second control quantity B2; A PD control module for performing negative feedback of the second control quantity B2 on the controller output quantity Y(s), inputting it into the PD controller, and superimposing the output result of the PD controller on the first control quantity B1 to form the negative feedback Y′(s).

7. The automatic throttle non-linear control device for fully automatic aircraft landing according to claim 6, characterized in that, In the feedforward lead-lag correction control module, the transfer function used for the feedforward lead-lag correction is where a and T are adjustment parameters, and s is the Laplace operator; Wherein, the adjustment parameter T is determined by the following formula: T = KL / (V ref · sinθ), where K is the aerodynamic correction coefficient, L is the runway length, θ is the glide angle, and V ref is the landing speed; The adjustment parameter a is determined by the following formula: a = 1.5 + 0.5ΔV / V ref , where ΔV is the real-time airspeed error.

8. The automatic throttle non-linear control device for fully automatic aircraft landing according to claim 6, characterized in that, In the automatic throttle execution module, the second time delay compensation time is obtained according to the statistics of the mechanical characteristics of multiple aircraft after installation.

9. The automatic throttle non-linear control device for fully automatic aircraft landing according to claim 6, characterized in that, In the PD control module, the time constant T of the PD controller D is determined by simulation.

10. The automatic throttle non-linear control device for fully automatic aircraft landing according to claim 6, characterized in that, In the PD control module, when superimposing the output result of the PD controller on the first control quantity B1, it further includes setting a proportionality coefficient Kp of the output result of the PD controller: Kp = η·(J / M) 0.5 ; Wherein, J is the engine moment of inertia, M is the aircraft mass, and η is a damping correction factor with a value range of 0.8 to 1.2.

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