An adaptive control method and system for an aircraft fuel tank environment simulation device

Abstract

The present application provides an adaptive control method and system for an aircraft fuel tank environment simulation device, the method comprising: obtaining the working state that the air tank pressure control system needs to control to enter; when it is necessary to enter the air pressure regulation working state, calculating and obtaining the given opening of the regulating valve of the air tank based on the adaptive PID control algorithm; wherein, the adaptive PID control algorithm, calculating and obtaining the given opening of the regulating valve of the air tank, comprises: obtaining the pressure deviation; obtaining the current slope absolute value of the pressure given value curve; obtaining the current internal and external pressure difference; calculating and obtaining the given opening of the regulating valve according to the pressure deviation, the current slope absolute value and the current internal and external pressure difference; linear mapping pressure difference compensation, calculating the given opening of the output regulating valve; when it is necessary to enter the closed state, controlling the regulating valve of the air tank to close. The present application obtains the control opening of the regulating valve of the air tank by adaptive calculation, so that the air tank pressure control system can simultaneously meet the requirements of high dynamic characteristics and high-precision control in steady state.

Description

Technical Field

[0001] The present application relates to the technical field of aircraft fuel tank environment simulation device control, and in particular to an adaptive control method and system for an aircraft fuel tank environment simulation device. Background Art

[0002] During the flight of an aircraft, in order to ensure the continuous supply of fuel, prevent the explosion and fire of the fuel tank, and prevent the appearance of bubbles in the fuel due to the decrease in external air pressure, a fuel tank ventilation and pressurization system is set up to introduce inert gas into the fuel tank and keep a certain positive pressure in the fuel tank against the external environment. The pressure of the ventilation and pressurization system comes from the engine bleed air system and the speed pressure port. During the design phase of the aircraft fuel system, the ventilation and pressurization system of the fuel tank needs to be verified and tested through ground experiments. The environmental simulation device of the aircraft fuel tank ventilation and pressurization system usually has three air boxes, and the pressure in the air boxes is continuously controllable, which simulates the changes of bleed air pressure, speed pressure and environmental air pressure under a flight profile. In order to fully test the performance and reliability of the ventilation and pressurization system of the aircraft under harsh conditions, different working conditions, different speeds and different altitudes, there are relatively high requirements for the real-time performance, control accuracy and dynamic response speed of the ventilation and pressurization system air pressure simulation device.

[0003] The structure of the air box pressure control system is as follows: Figure 1 As shown, the pressure gas source provides a stable high-pressure gas source. If there is a negative pressure requirement in the air box, the exhaust valve is connected to the vacuum gas source. If there is no negative pressure requirement, it is directly connected to the atmosphere. By adjusting the opening of the intake valve, the pressure rise rate in the air box can be adjusted. By adjusting the opening of the exhaust valve, the pressure drop rate in the air box can be adjusted. The differential control method is used to decide whether to open the intake valve or the exhaust valve, and the size of its opening, according to the difference between the air pressure target value and the measured pressure value, that is, the control deviation e. At a certain moment, only one of them is opened and the other is closed, which can control the pressure in the air box to be stable at the pressure setting value. In order to improve the dynamic response rate of the system, the control valve adopts a hydraulically powered control valve, and its action time is generally in milliseconds.

[0004] The traditional air tank pressure control method has the following problems:

[0005] 1. The nonlinearity in the fuel tank ventilation and pressurization system of the traditional control method causes the dynamic response rate of the system to fail to meet higher requirements. For example, when the gas passes through a regulating valve with a certain opening, the mass flow of the gas is proportional to the pressure difference at both ends. During the stage of rising pressure, the difference between the pressure inside the gas tank and the pressure of the gas source gradually decreases, and the air flow decreases, resulting in a decrease in the rate of pressure increase. This problem also exists during the stage of falling pressure. When the pressure difference between the inside and outside of the gas tank becomes smaller, the regulating effect of the regulating valve becomes weaker;

[0006] 2. A set of control parameters of the traditional PID control algorithm is difficult to simultaneously meet the requirements of high dynamic characteristics and high precision in steady state;

[0007] 3. Due to the existence of disturbances, the differential air pressure control system fluctuates near the equilibrium point, which will cause the intake valve and exhaust valve to jump frequently, and switch alternately between the adjustment and closing states, which will cause the valve sealing system to wear out too quickly and reduce the service life of the valve. Summary of the invention

[0008] The present application provides an adaptive control method for an aircraft fuel tank environment simulation device, which can solve the technical problems that the traditional PID control algorithm used in the prior art for tank pressure control cannot simultaneously meet the high dynamic characteristics and high precision requirements in steady state, and the dynamic response rate cannot meet higher requirements.

[0009] In a first aspect, the present application provides an adaptive control method for an aircraft fuel tank environment simulation device, comprising the following steps:

[0010] Obtain the working state that the air tank pressure control system needs to control to enter;

[0011] When the air box pressure control system needs to enter the air pressure regulation working state, the given opening of the regulating valve of the air box is calculated and obtained based on the adaptive PID control algorithm, and the regulating valve of the air box is controlled to execute the obtained given opening;

[0012] The method of calculating and obtaining a given opening of the regulating valve of the air box based on the adaptive PID control algorithm specifically includes the following steps:

[0013] Obtain the pressure deviation existing before the gas tank pressure is adjusted;

[0014] Get the current absolute value of the slope of the pressure setpoint curve of the gas tank pressure regulation control;

[0015] Get the current internal and external pressure difference of the gas tank;

[0016] The given opening of the regulating valve is calculated based on the pressure deviation before the gas tank pressure is adjusted, the current slope absolute value and the current internal and external pressure difference of the gas tank;

[0017] When the air tank pressure control system needs to enter a closed state, the regulating valve of the control air tank is closed.

[0018] In combination with the first aspect, in one implementation, obtaining the working state that the air box pressure control system needs to control to enter specifically includes the following steps:

[0019] Get the measured pressure of the gas tank;

[0020] Obtain the target pressure that the gas tank pressure control expects to achieve;

[0021] Compare the measured pressure of the gas tank with the target pressure, and obtain the working state that the gas tank pressure control system needs to enter based on the comparison result.

[0022] In combination with the first aspect, in one implementation, the step of calculating and obtaining a given opening of the regulating valve according to the pressure deviation existing before the air tank pressure is adjusted, the current slope absolute value, and the current internal and external pressure difference of the air tank specifically includes the following steps:

[0023] According to the pressure deviation existing before the air box pressure is adjusted, the integral term and the differential term of the adaptive PID control algorithm are calculated;

[0024] The current slope absolute value of the air tank pressure set value curve is processed by the limit output, and the SPL value is output. According to the SPL value, the dynamically adjusted PID parameters are obtained;

[0025] According to the obtained integral term and differential term and the dynamically adjusted PID parameters, the control quantity required for the air box pressure regulation is calculated;

[0026] Compensation calculation is performed on the acquired control quantity according to the current internal and external pressure difference of the air box to obtain the pressure difference compensation value required for air box pressure regulation;

[0027] The control quantity obtained by the pressure difference compensation value is linearly mapped to calculate and obtain the given opening of the regulating valve.

[0028] In combination with the first aspect, in one implementation, the dynamically adjusted PID parameters are obtained according to the SPL value, as shown in the following formula:

[0029] P = (1 + SPL * CO) * iaP;

[0030] I = (1 + SPL * CO) * iaI;

[0031] D = (1 + SPL * CO) * iaD;

[0032] Where iaP, iaI, iaD are pre-set PID parameters, CO is the speed adjustment coefficient, and P, I, D are dynamically adjusted PID parameters.

[0033] In combination with the first aspect, in one implementation, the control amount required for adjusting the air box pressure is calculated based on the obtained integral term and differential term and the dynamically adjusted PID parameters, as shown in the following formula:

[0034] UK=P*e+I*Ie+D*De;

[0035] In the formula, UK is the control quantity before pressure difference compensation, e is the control deviation, P, I, D are the PID coefficients after dynamic adjustment, Ie and De are the integral term and differential term respectively.

[0036] In combination with the first aspect, in one implementation, the obtained control amount is compensated and calculated according to the current internal and external pressure difference of the air box to obtain the pressure difference compensation value required for air box pressure regulation, as shown in the following formula:

[0037] UK'=UK*(1+DP_CO*DP / DP_MAX);

[0038] In the formula, UK' is the control amount after pressure difference compensation, UK is the control amount before pressure difference compensation, DP is the current internal and external pressure difference of the air box, DP_CO is the control amount coefficient after pressure difference compensation, and DP_MAX is the maximum pressure difference.

[0039] In combination with the first aspect, in one embodiment, when the air box pressure control system needs to enter the air pressure regulation working state, the given opening of the regulating valve of the air box is calculated based on the adaptive PID control algorithm, and after the regulating valve of the air box is controlled to execute the obtained given opening, the following steps are also included:

[0040] Continuously obtain the measured pressure of the gas tank;

[0041] Compare the measured pressure with the target pressure;

[0042] When the difference between the measured pressure and the target pressure is greater than a first preset difference, the air box is controlled to enter a closed state from an intake pressurization state;

[0043] When the difference between the measured pressure and the target pressure is greater than a second preset difference, the control air box enters a closed state from an exhaust and decompression state.

[0044] In combination with the first aspect, in one embodiment, when the air box pressure control system needs to enter a closed state, after the regulating valve of the control air box is closed, the following steps are further included:

[0045] Zero the integral term of the adaptive PID control algorithm and continuously obtain the measured pressure of the gas box;

[0046] Compare the measured pressure with the target pressure;

[0047] When the difference between the measured pressure and the target pressure is greater than a first preset difference, the air box is controlled to enter an intake boost state from a closed state;

[0048] When the difference between the measured pressure and the target pressure is greater than a second preset difference, the air box is controlled to enter an exhaust and decompression state from a closed state.

[0049] In a second aspect, the present application provides an adaptive control system for an aircraft fuel tank environment simulation device, comprising:

[0050] An air box working state acquisition module is used to acquire the working state that the air box pressure control system needs to control to enter;

[0051] A regulating valve opening control module is in communication with the air box working state acquisition module, and is used to calculate and acquire a given opening of the regulating valve of the air box based on an adaptive PID control algorithm when the air box pressure control system needs to enter the air pressure regulation working state, and control the regulating valve of the air box to execute the acquired given opening;

[0052] Wherein, the method of calculating and obtaining a given opening of the regulating valve of the air box based on the adaptive PID control algorithm includes:

[0053] Obtain the pressure deviation existing before the gas tank pressure is adjusted;

[0054] Get the current absolute value of the slope of the pressure setpoint curve of the gas tank pressure regulation control;

[0055] Get the current internal and external pressure difference of the gas tank;

[0056] The given opening of the regulating valve is calculated based on the pressure deviation before the gas tank pressure is adjusted, the current slope absolute value and the current internal and external pressure difference of the gas tank;

[0057] The regulating valve closing control module is communicated with the gas box working status acquisition module and is used to control the closing of the regulating valve of the gas box when the gas box pressure control system needs to enter the closed state.

[0058] In conjunction with the second aspect, in one implementation, the air box working state acquisition module includes:

[0059] A measured pressure acquisition unit, used to acquire the measured pressure of the gas box;

[0060] A target pressure acquisition unit, used to acquire the target pressure expected to be achieved by the air tank pressure control;

[0061] The air box working state acquisition unit is communicatively connected with the measured pressure acquisition unit and the target pressure acquisition unit, and is used to compare the measured pressure of the air box with the target pressure, and obtain the working state that the air box pressure control system needs to control to enter according to the comparison result.

[0062] The beneficial effects brought by the technical solution provided by the embodiment of the present application include at least:

[0063] By obtaining the three variables of pressure deviation, the absolute value of the current slope of the pressure set value curve and the pressure difference between the inside and outside of the air box, the regulating valve control opening of the air box can be adaptively calculated to achieve adaptive adjustment and control of the valve opening, so that the air box pressure control system can meet both high dynamic characteristics and high-precision control requirements in steady state. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 It is the structural diagram of the air box pressure control system;

[0065] Figure 2 A schematic flow chart of an adaptive control method for an aircraft fuel tank environment simulation device provided in an embodiment of the present application;

[0066] Figure 3 Flow chart of the adaptive PID control algorithm provided in the embodiment of the present application;

[0067] Figure 4 An example of an input and output diagram of an adaptive PID controller provided in an embodiment of the present application;

[0068] Figure 5 A schematic diagram of the working state switching of the air box pressure control system in the differential air pressure control algorithm with hysteresis provided in an embodiment of the present application;

[0069] Figure 6 This is a control schematic diagram of the aircraft fuel tank ventilation and pressurization system environment simulation device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0070] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0071] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0072] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0073] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0074] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0075] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0076] The present application provides an adaptive control method for an aircraft fuel tank environment simulation device, which is applicable to the pressure control of an air box in an environment simulation device in an aircraft fuel tank ventilation and pressurization system, wherein the air box is a bleed air box, a rapid pressure air box and an environmental air box, and the regulating valve includes an intake valve and an exhaust valve, please refer to Figure 2 , specifically including the following steps:

[0077] Step S1: obtaining the working state that the air box pressure control system needs to control to enter;

[0078] Step S2: When the air box pressure control system needs to enter the air pressure regulation working state, the given opening of the regulating valve of the air box is calculated based on the adaptive PID control algorithm, and the regulating valve of the air box is controlled to execute the obtained given opening; specifically, in the intake supercharging state, the intake valve opening is regulated and controlled; in the exhaust decompression state, the exhaust valve opening is regulated and controlled;

[0079] Among them, Figure 3 As shown, in step S2, the given opening of the regulating valve of the air box is calculated based on the adaptive PID control algorithm, which specifically includes the following steps:

[0080] Step S21: obtaining the pressure deviation existing before the air tank pressure is adjusted;

[0081] Step S22: obtaining the current absolute value of the slope of the pressure setpoint curve of the air tank pressure regulation control;

[0082] Step S23: obtaining the current pressure difference between the inside and outside of the air box; specifically, when controlling the opening of the intake valve, the pressure difference between the inside and outside of the air box is the pressure difference between the pressure gas source and the gas in the air box; when controlling the opening of the exhaust valve, the pressure difference is the pressure difference between the air pressure in the air box and the vacuum source or the atmosphere;

[0083] Step S24: Calculate and obtain a given opening of the regulating valve according to the pressure deviation existing before the air tank pressure is adjusted, the current slope absolute value, and the current internal and external pressure difference of the air tank;

[0084] Step S3: When the air tank pressure control system needs to enter a closed state, the regulating valve of the control air tank is closed.

[0085] The present application can adaptively calculate and obtain the regulating valve control opening of the air box by obtaining three variables, namely, the pressure deviation, the absolute value of the current slope of the pressure set value curve, and the pressure difference between the inside and outside of the air box, to achieve adaptive regulation and control of the valve opening. The application has a simple algorithm and a small amount of calculation, and is suitable for occasions with high real-time requirements. The static and dynamic performance of the regulating valve opening control are met at the same time, and the control accuracy, stability, and response rate can meet higher requirements.

[0086] like Figure 4 As shown, the adaptive PID control algorithm provided in the present application is implanted into the PID controller. By inputting three variables, namely the pressure error e, the absolute value SPL of the current slope of the pressure set value curve, and the pressure difference DP inside and outside the air box, the PID controller calculates and processes the output of the regulating valve to set the opening, thereby controlling the two actuators of the intake valve and the exhaust valve.

[0087] In one embodiment, the step S1: obtaining the working state that the air box pressure control system needs to control to enter specifically includes the following steps:

[0088] Step S11: obtaining the measured pressure of the air box;

[0089] Step S12: obtaining the target pressure that the air tank pressure control expects to achieve;

[0090] Step S13: Compare the measured pressure of the air box with the target pressure, and obtain the working state that the air box pressure control system needs to control to enter according to the comparison result; specifically:

[0091] Step S131: when the measured pressure of the air box is less than the target pressure, it is determined that the working state to be controlled by the air box pressure regulation is the intake boost state;

[0092] Step S132: when the measured pressure of the air box is greater than the target pressure, it is determined that the working state to be controlled to enter the air box pressure regulation is the exhaust pressure reduction state;

[0093] Step S133: When the preset closing condition is met during the execution of the air pressure regulation control process for the air box, it is determined that the working state required for the air box pressure regulation to be controlled is the closed state; wherein, the preset closing condition may be that in the intake boost state, the air box actually measured pressure increases to the target pressure; in the exhaust decompression state, the air box actually measured pressure decreases to the target pressure; preferably, in order to avoid frequent jumping of the intake valve and the exhaust valve under balanced conditions, in the intake boost state, the preset closing condition is that the air box actually measured pressure increases by a very small amount △u exceeding the target pressure; in the exhaust decompression state, the preset closing condition is that the air box actually measured pressure decreases by a very small amount △d below the target pressure.

[0094] In one embodiment, step S21: obtaining the pressure deviation existing before the air box pressure is adjusted; specifically includes the following steps:

[0095] Step S211: sampling the current measured pressure in the gas box;

[0096] Step S212: obtaining the target pressure that the air tank pressure control expects to achieve according to the air tank pressure given value curve;

[0097] Step S213: Calculate and obtain the pressure deviation before the air tank pressure is adjusted according to the following formula:

[0098] e=TM;

[0099] Where e is the pressure deviation, T is the target pressure, and M is the measured pressure.

[0100] In one embodiment, the step S24: calculating and obtaining a given opening of the regulating valve according to the pressure deviation existing before the air tank pressure is adjusted, the current slope absolute value, and the current internal and external pressure difference of the air tank, specifically includes the following steps:

[0101] Step S241: according to the pressure deviation before the air box pressure is adjusted, the integral term and the differential term of the adaptive PID control algorithm are calculated; specifically, according to the traditional PID formula, the integral term Ie and the differential term De are calculated and output with limited amplitude;

[0102] Step S242: limiting the output processing of the current slope absolute value SP of the air box pressure set value curve, outputting the SPL value, and obtaining the dynamically adjusted PID parameters according to the SPL value;

[0103] Step S243: Calculate and obtain the control amount required for adjusting the air box pressure according to the obtained integral term and differential term and the dynamically adjusted PID parameters;

[0104] Step S244: performing compensation calculation on the acquired control amount according to the current internal and external pressure difference of the air box to obtain the pressure difference compensation value required for air box pressure regulation;

[0105] Step S245: linearly map the control amount obtained by the pressure difference compensation value to calculate and obtain the given opening of the regulating valve.

[0106] In one embodiment, the absolute value SPL of the current slope of the given value curve reflects the current expected pressure change rate. When the expected change rate is large, increasing the PID control coefficient can reduce the adjustment time and improve the response speed of the system; when the expected change rate is very small, such as constant value control, the slope of the given value curve is 0; when the expected change rate is small, a relatively small PID control coefficient is applied, which is beneficial to the stability of the air box pressure control system and reduces the dynamic adjustment time and the number of oscillations. In step S242, the dynamically adjusted PID parameters are obtained according to the SPL value, as shown in the following formula:

[0107] P = (1 + SPL * CO) * iaP;

[0108] I = (1 + SPL * CO) * iaI;

[0109] D = (1 + SPL * CO) * iaD;

[0110] Where iaP, iaI, iaD are pre-set PID parameters, CO is the speed adjustment coefficient, and P, I, D are dynamically adjusted PID parameters.

[0111] The adaptive PID control algorithm provided in step S242 dynamically adjusts the PID control parameters based on the slope of the given value curve, so that the stable accuracy and dynamic response rate of the opening control of the regulating valve are satisfied at the same time.

[0112] In one embodiment, the adaptive PID algorithm provided by the present application designs the pressure difference between the inside and outside of the air box as a control quantity, and the control quantity includes a proportional term, an integral term and a differential term, and its calculation method is the same as that of the traditional PID algorithm. Specifically, the step S243: according to the obtained integral term and differential term and the dynamically adjusted PID parameters, the control quantity required for the air box pressure regulation is calculated, as shown in the following formula:

[0113] UK=P*e+I*Ie+D*De;

[0114] In the formula, UK is the control quantity before pressure difference compensation, e is the control deviation, P, I, D are the PID coefficients after dynamic adjustment, Ie and De are the integral term and differential term respectively.

[0115] In one embodiment, considering that during intake, as the pressure in the air box rises, the pressure difference between the inside and outside of the air box decreases, and the intake flow rate decreases, it is necessary to increase the control amount to compensate for the decrease in response rate; similarly, during exhaust, as the pressure in the air box decreases, the pressure difference between the inside of the air box and the vacuum source or the atmosphere decreases, and the exhaust flow rate decreases, and it is also necessary to increase the control amount. The adaptive PID control algorithm provided in the present application calculates the pressure difference compensation by the DP value. The step S244: performing compensation calculation on the acquired control amount according to the current pressure difference between the inside and outside of the air box to obtain the pressure difference compensation value required for air box pressure regulation specifically includes the following steps:

[0116] UK'=UK*(1+DP_CO*DP / DP_MAX);

[0117] In the formula, UK' is the control amount after pressure difference compensation, UK is the control amount before pressure difference compensation, DP is the current internal and external pressure difference of the air box, DP_CO is the control amount coefficient after pressure difference compensation, and DP_MAX is the maximum pressure difference.

[0118] Based on step S244, the opening control response rate is compensated by the current internal and external pressure difference of the air box, compensating for the change in the dynamic response rate of the opening control of the regulating valve caused by the change in the air pressure in the air box and the pressure difference of the air source, thereby ensuring that the dynamic response rate of the opening control of the regulating valve meets the requirements.

[0119] In one embodiment, in order to solve the problem that the intake valve and the exhaust valve frequently jump at the equilibrium point due to the presence of disturbance in the traditional regulating valve opening control method, after step S2 and step S3, as shown in FIG. Figure 5 As shown, the present application provides a differential air pressure control algorithm with hysteresis loop to achieve the control switching of the subsequent air box working state, specifically:

[0120] After starting the differential adaptive air pressure control method with hysteresis, the differential air pressure control system enters the adjustment state from the initial state, and then switches between the three working states of intake boost state, exhaust decompression state, and closed state according to the relative changes of the target pressure T and the measured pressure M in the air box.

[0121] Since the hysteresis loop is added to the differential air pressure control algorithm with hysteresis loop, the number of valve actions is reduced. For example, when boosting, the exhaust valve is in the closed state, and the intake valve opening is calculated by the adaptive PID control algorithm according to the pressure deviation, and the intake valve controller performs the opening control. The pressure in the air box rises until the measured pressure M exceeds the target pressure T by a very small amount △u, and then enters the closed state. When the given value curve is a pressure reduction, the intake valve is closed, and the exhaust valve opening is calculated by the adaptive PID control algorithm according to the pressure deviation, and the exhaust valve controller performs the opening control. The pressure in the air box drops until the measured pressure M is lower than the target pressure T by a very small amount △d, and then enters the closed state. The introduction of △d and △u reduces the number of actions of the regulating valve and extends the service life of the regulating valve, but it will also introduce control accuracy errors. In the actual control process, their sizes can be reasonably set under the premise of ensuring control accuracy. The integral term in the algorithm has a memory characteristic. In the differential air pressure control algorithm with hysteresis, when the intake and exhaust states are switched, the integral term must be set to zero to ensure that the intake valve control and the exhaust valve control are not coupled.

[0122] In one embodiment, the step S2: when the air box pressure control system needs to enter the air pressure regulation working state, the given opening of the regulating valve of the air box is calculated and obtained based on the adaptive PID control algorithm, and after the regulating valve of the air box is controlled to execute the obtained given opening, the following steps are also included:

[0123] Continuously obtain the measured pressure of the gas tank;

[0124] Compare the measured pressure with the target pressure;

[0125] When the air box is in an intake boost state and the difference between the measured pressure of the air box and the target pressure is greater than a first preset difference △u, the air box is controlled to enter a closed state from the intake boost state;

[0126] When the air box is in an exhaust and decompression state and the difference between the actual pressure of the air box and the target pressure is greater than a second preset difference △d, the air box is controlled to enter a closed state from the exhaust and decompression state.

[0127] In one embodiment, step S3: when the air box pressure control system needs to enter a closed state, after the regulating valve of the control air box is closed, the following steps are also included:

[0128] Zero the integral term of the adaptive PID control algorithm and continuously obtain the measured pressure of the gas box;

[0129] Compare the measured pressure with the target pressure;

[0130] When the air box is in a closed state and the difference between the measured pressure and the target pressure is greater than a first preset difference, the air box is controlled to enter an intake pressurization state from a closed state;

[0131] When the air box is in the closed state and the difference between the measured pressure and the target pressure is greater than the second preset difference, control the air box to enter the exhaust and decompression state from the closed state.

[0132] In a more specific embodiment, as Figure 5 shown, the differential air box air pressure control algorithm with hysteresis is implemented as follows:

[0133] Step 1: Sample the air pressure value M in the air box. According to the air box pressure set value curve, obtain the current control target T and the current slope SP in the set value curve, calculate the control deviation e = T - M, and determine whether to enter the air intake and pressurization state, the exhaust and decompression state or the closed state according to the difference between T and M. If T > M, then enter Step 2, that is, the air intake and pressurization state; if T < M, then enter Step 3, that is, the exhaust and decompression state.

[0134] Step 2: Enter the air intake and pressurization state, perform the following control actions, run the above-mentioned adaptive PID control algorithm, calculate the given opening of the regulating valve, close the exhaust valve, send the calculated given opening of the regulating valve to the intake valve controller, perform opening control, open the intake valve to the given opening, then the air pressure in the air box rises, regularly refresh the values of T and M, and loop to execute the above actions until the measured pressure M exceeds the desired pressure T by a small amount △u, then enter Step S4, that is, the closed state.

[0135] Step 3: Enter the exhaust and decompression state, perform the following control actions, run the above-mentioned adaptive PID control algorithm, calculate the given opening of the regulating valve. Close the intake valve, send the calculated given opening of the regulating valve to the exhaust valve controller, perform opening control, open the exhaust valve to the given opening, then the air pressure in the air box drops, regularly refresh the values of T and M, and loop to execute the above actions until the measured pressure M is lower than the desired pressure T by a small amount △d, then enter Step S4, that is, the closed state.

[0136] Step 4: Enter the closed state, close the intake valve and the exhaust valve, and set the integral term Ie of the above-mentioned adaptive PID control algorithm to zero. Regularly loop to perform the following control actions, refresh the values of T and M. If T - M > △d, then enter Step 2; if M - T > △u, then enter Step 4, otherwise stay in the closed state, and loop to execute the above actions.

[0137] In an embodiment, as Figure 6 shown, the control principle of the aircraft fuel tank ventilation and pressurization system environment simulation device is as follows:

[0138] According to the air box pressure set value curve, obtain the target pressure that the air box pressure control is expected to reach;

[0139] Measure and obtain the measured pressure of the air box;

[0140] Calculate and obtain the pressure deviation based on the target pressure and the measured pressure;

[0141] The intake valve pressure difference or the exhaust valve pressure difference, that is, the air box pressure difference and the pressure deviation are obtained, and the opening set value of the regulating valve is calculated through the adaptive PID control algorithm. Combined with the differential controller implanted with the differential air box pressure control algorithm with hysteresis loop, the opening set value is output to the intake valve controller or the exhaust valve controller to perform opening control on the intake regulating valve or the exhaust regulating valve, and the intake high-pressure air source is used, or the inert gas is discharged to the vacuum source or the atmosphere, so as to realize the regulation and control of the air pressure in the air box, so that the oil tank maintains a certain positive pressure against the external environment.

[0142] The present application adopts the same control scheme and algorithm for the three air boxes of bleed air, rapid pressure and environment set up in the environmental simulation device of the aircraft fuel tank ventilation and pressurization system. During actual control, the three air boxes can adopt different control parameters according to the static and dynamic performance requirements to achieve the performance requirements of the system.

[0143] In a second aspect, the present application provides an adaptive control system for an aircraft fuel tank environment simulation device, comprising:

[0144] An air box working state acquisition module is used to acquire the working state that the air box pressure control system needs to control to enter;

[0145] A regulating valve opening control module is in communication with the air box working state acquisition module, and is used to obtain a given opening of the regulating valve based on an adaptive PID control algorithm when the air box pressure control system needs to enter the air pressure regulation working state, and to control the regulating valve of the air box to execute the obtained given opening;

[0146] The method of calculating and obtaining a given opening of the regulating valve of the air box based on the adaptive PID control algorithm specifically includes the following steps:

[0147] Obtain the pressure deviation existing before the gas tank pressure is adjusted;

[0148] Get the current absolute value of the slope of the pressure setpoint curve of the gas tank pressure regulation control;

[0149] Get the current internal and external pressure difference of the gas tank;

[0150] The given opening of the regulating valve is calculated based on the pressure deviation before the gas tank pressure is adjusted, the current slope absolute value and the current internal and external pressure difference of the gas tank;

[0151] The regulating valve closing control module is communicated with the gas box working status acquisition module and is used to control the closing of the regulating valve of the gas box when the gas box pressure control system needs to enter the closed state.

[0152] In one embodiment, the air box working status acquisition module includes:

[0153] A measured pressure acquisition unit, used to acquire the measured pressure of the gas box;

[0154] A target pressure acquisition unit, used to acquire the target pressure expected to be achieved by the air tank pressure control;

[0155] The air box working state acquisition unit is communicatively connected with the measured pressure acquisition unit and the target pressure acquisition unit, and is used to compare the measured pressure of the air box with the target pressure, and obtain the working state that the air box pressure control system needs to control to enter according to the comparison result.

[0156] Among them, the functional implementation of each module in the adaptive control system of the above-mentioned aircraft fuel tank environment simulation device corresponds to the various steps in the adaptive control method embodiment of the above-mentioned aircraft fuel tank environment simulation device, and its functions and implementation processes will not be repeated here one by one.

[0157] In a third aspect, an embodiment of the present application also provides a readable storage medium.

[0158] The readable storage medium of the present application stores an adaptive control program of an aircraft fuel tank environment simulation device, wherein when the adaptive control program of the aircraft fuel tank environment simulation device is executed by a processor, the steps of the adaptive control method of the aircraft fuel tank environment simulation device as described above are implemented.

[0159] Among them, the method implemented when the adaptive control program of the aircraft fuel tank environment simulation device is executed can refer to the various embodiments of the adaptive control method of the aircraft fuel tank environment simulation device of the present application, and will not be repeated here.

[0160] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0161] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0162] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An adaptive control method for an aircraft fuel tank environment simulation device, characterized in that: The following steps are involved: Obtain the working state that the air tank pressure control system needs to control to enter; When the air box pressure control system needs to enter the air pressure regulation working state, the given opening of the regulating valve of the air box is calculated and obtained based on the adaptive PID control algorithm, and the regulating valve of the air box is controlled to execute the obtained given opening; The method of calculating and obtaining a given opening of the regulating valve of the air box based on the adaptive PID control algorithm specifically includes the following steps: Obtain the pressure deviation existing before the gas tank pressure is adjusted; Get the current absolute value of the slope of the pressure setpoint curve of the gas tank pressure regulation control; Get the current internal and external pressure difference of the gas tank; The given opening of the regulating valve is calculated based on the pressure deviation before the gas tank pressure is adjusted, the current slope absolute value and the current internal and external pressure difference of the gas tank; The method of calculating and obtaining a given opening of the regulating valve according to the pressure deviation existing before the air tank pressure is adjusted, the current slope absolute value, and the current internal and external pressure difference of the air tank specifically includes the following steps: According to the pressure deviation existing before the air box pressure is adjusted, the integral term and the differential term of the adaptive PID control algorithm are calculated; The current slope absolute value of the air tank pressure set value curve is processed by the limit output, and the SPL value is output. According to the SPL value, the dynamically adjusted PID parameters are obtained; According to the obtained integral term and differential term and the dynamically adjusted PID parameters, the control quantity required for the air box pressure regulation is calculated; Compensation calculation is performed on the acquired control quantity according to the current internal and external pressure difference of the air box to obtain the pressure difference compensation value required for air box pressure regulation; The obtained control amount is compensated and calculated according to the current internal and external pressure difference of the air box to obtain the pressure difference compensation value required for air box pressure regulation, as shown in the following formula: UK'=UK*(1+DP_CO*DP / DP_MAX); In the formula, UK' is the control amount after pressure difference compensation, UK is the control amount before pressure difference compensation, DP is the current internal and external pressure difference of the gas box, DP_CO is the control amount coefficient after pressure difference compensation, and DP_MAX is the maximum pressure difference; Performing linear mapping processing on the control quantity obtained by the pressure difference compensation value, and calculating and obtaining the given opening of the regulating valve; When the air tank pressure control system needs to enter a closed state, the regulating valve of the control air tank is closed.

2. The adaptive control method of the aircraft fuel tank environment simulation device according to claim 1, characterized in that: The step of obtaining the working state that the air box pressure control system needs to control to enter specifically includes the following steps: Get the measured pressure of the gas tank; Obtain the target pressure that the gas tank pressure control expects to achieve; Compare the measured pressure of the gas tank with the target pressure, and obtain the working state that the gas tank pressure control system needs to enter based on the comparison result.

3. The adaptive control method of the aircraft fuel tank environment simulation device according to claim 1, characterized in that: According to the SPL value, the dynamically adjusted PID parameters are obtained, as shown in the following formula: P = (1 + SPL * CO) * iaP; I = (1 + SPL * CO) * iaI; D = (1 + SPL * CO) * iaD; Where iaP, iaI, iaD are pre-set PID parameters, CO is the speed adjustment coefficient, and P, I, D are dynamically adjusted PID parameters.

4. The adaptive control method of the aircraft fuel tank environment simulation device according to claim 1, characterized in that: The control amount required for air box pressure regulation is calculated based on the obtained integral term and differential term and the dynamically adjusted PID parameters, as shown in the following formula: UK=P*e+I*Ie+D*De; In the formula, UK is the control quantity before pressure difference compensation, e is the control deviation, P, I, D are the PID coefficients after dynamic adjustment, Ie and De are the integral term and differential term respectively.

5. The adaptive control method of the aircraft fuel tank environment simulation device according to claim 1, characterized in that: When the air box pressure control system needs to enter the air pressure regulation working state, the given opening of the regulating valve of the air box is calculated based on the adaptive PID control algorithm, and after the regulating valve of the air box is controlled to execute the obtained given opening, the following steps are also included: Continuously obtain the measured pressure of the gas tank; Compare the measured pressure with the target pressure; When the difference between the measured pressure and the target pressure is greater than a first preset difference, the air box is controlled to enter a closed state from an intake pressurization state; When the difference between the measured pressure and the target pressure is greater than a second preset difference, the control air box enters a closed state from an exhaust and decompression state.

6. The adaptive control method of the aircraft fuel tank environment simulation device according to claim 1, characterized in that: When the air tank pressure control system needs to enter the closed state, after the regulating valve of the control air tank is closed, the following steps are also included: Zero the integral term of the adaptive PID control algorithm and continuously obtain the measured pressure of the gas box; Compare the measured pressure with the target pressure; When the difference between the measured pressure and the target pressure is greater than a first preset difference, the air box is controlled to enter an intake boost state from a closed state; When the difference between the measured pressure and the target pressure is greater than a second preset difference, the air box is controlled to enter an exhaust and decompression state from a closed state.

7. An adaptive control system for an aircraft fuel tank environment simulation device, characterized in that: include: An air box working state acquisition module is used to acquire the working state that the air box pressure control system needs to control to enter; A regulating valve opening control module is in communication with the air box working state acquisition module, and is used to calculate and acquire a given opening of the regulating valve of the air box based on an adaptive PID control algorithm when the air box pressure control system needs to enter the air pressure regulation working state, and control the regulating valve of the air box to execute the acquired given opening; Wherein, the method of calculating and obtaining a given opening of the regulating valve of the air box based on the adaptive PID control algorithm includes: Obtain the pressure deviation existing before the gas tank pressure is adjusted; Get the current absolute value of the slope of the pressure setpoint curve of the gas tank pressure regulation control; Get the current internal and external pressure difference of the gas tank; The given opening of the regulating valve is calculated based on the pressure deviation before the gas tank pressure is adjusted, the current slope absolute value and the current internal and external pressure difference of the gas tank; The method of calculating and obtaining a given opening of the regulating valve according to the pressure deviation existing before the air tank pressure is adjusted, the current slope absolute value, and the current internal and external pressure difference of the air tank includes: According to the pressure deviation existing before the air box pressure is adjusted, the integral term and the differential term of the adaptive PID control algorithm are calculated; The current slope absolute value of the air tank pressure set value curve is processed by the limit output, and the SPL value is output. According to the SPL value, the dynamically adjusted PID parameters are obtained; According to the obtained integral term and differential term and the dynamically adjusted PID parameters, the control quantity required for the air box pressure regulation is calculated; Compensation calculation is performed on the acquired control quantity according to the current internal and external pressure difference of the air box to obtain the pressure difference compensation value required for air box pressure regulation; The obtained control amount is compensated and calculated according to the current internal and external pressure difference of the air box to obtain the pressure difference compensation value required for air box pressure regulation, as shown in the following formula: UK'=UK*(1+DP_CO*DP / DP_MAX); In the formula, UK' is the control amount after pressure difference compensation, UK is the control amount before pressure difference compensation, DP is the current internal and external pressure difference of the gas box, DP_CO is the control amount coefficient after pressure difference compensation, and DP_MAX is the maximum pressure difference; The control quantity obtained by the pressure difference compensation value is linearly mapped to calculate and obtain the given opening of the regulating valve; the regulating valve closing control module is communicated with the air box working status acquisition module, and is used to control the closing of the regulating valve of the air box when the air box pressure control system needs to enter the closed state.

8. The adaptive control system of the aircraft fuel tank environment simulation device according to claim 7, characterized in that: The gas box working status acquisition module includes: A measured pressure acquisition unit, used to acquire the measured pressure of the gas box; A target pressure acquisition unit, used to acquire the target pressure expected to be achieved by the air tank pressure control; The air box working state acquisition unit is communicatively connected with the measured pressure acquisition unit and the target pressure acquisition unit, and is used to compare the measured pressure of the air box with the target pressure, and obtain the working state that the air box pressure control system needs to control to enter according to the comparison result.

Images