Methods for calculating angle of attack correction, stall protection methods, and stall protection systems

Abstract

The present application relates to a method for calculating an angle of attack correction, a stall protection method and a stall protection system. The method for calculating an angle of attack correction comprises: a first step of determining whether the lateral overload value needs to be corrected based on a left local angle of attack value, a right local angle of attack value and the lateral overload value, when the difference between the left local angle of attack value and the right local angle of attack value is greater than 0, if the lateral overload value is greater than or equal to 0, the lateral overload value is not corrected, and if the lateral overload value is less than 0, the lateral overload value is corrected, and when the difference between the right local angle of attack value and the left local angle of attack value is less than or equal to 0, if the lateral overload value is less than or equal to 0, the lateral overload value is not corrected, and if the lateral overload value is greater than 0, the lateral overload value is corrected; a second step of calculating the angle of attack correction by using the lateral overload value.

Description

Technical Field

[0001] This invention relates to a method for calculating angle-of-attack corrections for aircraft stall protection systems, which can prevent the aircraft from entering an unsafe stall state. This invention also relates to a stall protection method and a stall protection system. This invention belongs to the field of flight control systems. Background Technology

[0002] During flight, the angle of attack is closely related to the aircraft's lift and drag. Within a certain range, the larger the angle of attack, the greater the lift and drag coefficients. However, when the angle of attack exceeds a certain value (called the critical angle of attack), the lift and drag coefficients decrease, and the aircraft may stall.

[0003] A stall protection system is a control system that prevents civil aircraft from entering the unsafe state of a stall. When the actual angle of attack approaches the critical angle of attack, posing a risk of stall, the stall protection system is triggered and issues various forms of warning signals.

[0004] An angle-of-attack sensor is a device that measures the angle of attack of an aircraft. The angle-of-attack sensor measures the angle of attack of a local area by sensing the direction of the surrounding flow field and sends the angle of attack signal to the relevant system. The output of the angle-of-attack sensor is then compensated and calculated to become the true angle of attack of the aircraft.

[0005] Because the free airflow around a moving object is disturbed, the flow field around the angle of attack sensor cannot accurately reflect the aircraft's true angle of attack. This type of error is mainly determined by the installation position of the angle of attack sensor.

[0006] In existing technologies, as the aircraft's sideslip angle increases, the difference in measurement values ​​between the left and right local angle-of-attack sensors becomes larger. Therefore, the installation location of the angle-of-attack sensor is sensitive to the sideslip angle. Finding a location with low sensitivity and high accuracy to the sideslip angle presents significant challenges. The only solution is to measure the sideslip angle using a sideslip angle sensor, then use simulation formulas to reduce the impact of the sideslip angle and calculate the aircraft's true angle of attack.

[0007] However, existing sideslip angle sensors have difficulty acquiring sideslip angle data, and the sampling rate and accuracy are low. Triggering stall protection solely through flight parameter signal acquisition may reduce aircraft safety and could lead to pilot misjudgment.

[0008] Therefore, there is an urgent need to propose a stall protection method that reduces the sideslip angle sensitivity of the angle of attack signal, thereby improving the accuracy of the angle of attack signal and thus enhancing aircraft safety. Summary of the Invention

[0009] To address the aforementioned problems in the prior art, the present invention aims to provide a method for calculating angle of attack correction, a stall protection method, and a stall protection system, which can effectively reduce errors caused by sideslip angle sensitivity.

[0010] In a first example of the method for calculating the angle of attack correction according to the present invention, the method includes: a first step of determining whether a correction is needed for the lateral overload value based on the left local angle of attack value, the right local angle of attack value, and the lateral overload value, wherein when the difference between the left local angle of attack value and the right local angle of attack value is greater than 0, if the lateral overload value is greater than or equal to 0, no correction is made to the lateral overload value; and if the lateral overload value is less than 0, a correction is made to the lateral overload value. Furthermore, when the difference between the left local angle of attack value and the right local angle of attack value is less than or equal to 0, if the lateral overload value is less than or equal to 0, no correction is made to the lateral overload value; and if the lateral overload value is greater than 0, a correction is made to the lateral overload value. The second step is to calculate the angle of attack correction based on the lateral overload value. The stall protection system according to the present invention corrects the left local angle of attack value and the right local angle of attack value based on the lateral overload value. Compared with the sideslip angle signal from the sideslip angle sensor, the lateral overload signal from the corresponding sensor is more reliable, thus the system has high reliability.

[0011] In a second example of the method for calculating the angle of attack correction, the first example may be optionally included. The method for calculating the angle of attack correction further includes a third step: determining whether the angle of attack correction needs to be corrected. First, the absolute value of the difference obtained by subtracting the average value of the left local angle of attack value and the right local angle of attack value from the left local angle of attack value or the right local angle of attack value is taken as the first absolute value. Wherein, when the absolute value of the angle of attack correction is less than or equal to the first absolute value, the angle of attack correction is not corrected. Wherein, when the absolute value of the angle of attack correction is greater than the first absolute value, the angle of attack correction is corrected, keeping the sign of the angle of attack correction and correcting it so that the absolute value of the angle of attack correction is equal to the first absolute value.

[0012] In a third example of the method for calculating the angle of attack correction, one or more of the first and second examples may be optionally included. In the first step, when the difference between the left local angle of attack value and the right local angle of attack value is greater than 0, if the lateral overload value is less than 0, the lateral overload value is corrected, specifically by setting the lateral overload value to 0; and when the difference between the left local angle of attack value and the right local angle of attack value is less than or equal to 0, if the lateral overload value is greater than 0, the lateral overload value is corrected, specifically by setting the lateral overload value to 0.

[0013] In the fourth example of the method for calculating the angle of attack correction, one or more of the first to third examples may be optionally included. The first step further includes: sensing the lateral overload of the aircraft with the corresponding sensor, and processing the signal of the corresponding sensor, specifically performing low-pass filtering, to obtain the lateral overload value.

[0014] In the fifth example of the method for calculating the angle of attack correction, one or more of the first to fourth examples may be optionally included. The first step further includes: determining whether the lateral overload value needs to be corrected, wherein when the absolute value of the lateral overload value is less than or equal to a preset lateral overload threshold value, the lateral overload value is not corrected, and wherein when the absolute value of the lateral overload value is greater than the lateral overload threshold value, the lateral overload value is corrected, maintaining the sign of the lateral overload value and correcting it so that the absolute value of the lateral overload value is equal to the lateral overload threshold value.

[0015] In a sixth example of the method for calculating the angle of attack correction, one or more of the first to fifth examples may be optionally included. In the second step, the angle of attack correction is calculated using a first formula based on the lateral overload value, wherein the first formula is Δα. LOCAL =(CY2xNy 2 )+(CY1xNy 1 )+CY0, where CY2, CY1, and CY0 are preset quadratic correction coefficients, linear correction coefficients, and constant correction coefficients.

[0016] In the seventh example of the method for calculating the angle of attack correction, one or more of the first to sixth examples may be optionally included. The second step further includes: the quadratic correction coefficient, the first-order correction coefficient, and the constant correction coefficient are calculated based on flight parameters and influencing factors, wherein the influencing factors include speed, weight, aerodynamic derivative, and center of gravity, and the flight parameters are sensed by corresponding sensors, wherein the flight parameters include Mach number, flap / slat positioning, icing conditions, and fault conditions, and the flight parameters are preset.

[0017] According to a stall protection method of the present invention, for use in a stall protection system, the method includes: step a, sensing the flight parameters of the aircraft using corresponding sensors, and calculating the stick-jumping stall protection angle of attack value and the stick-pull-up stall protection angle of attack value based on the flight parameters, wherein the flight parameters include Mach number, flap / slat positioning, icing conditions, and fault conditions; step b, sensing the left local angle of attack and the right local angle of attack of the aircraft using corresponding sensors, processing the signals of the corresponding sensors to obtain the left local angle of attack value and the right local angle of attack value, and determining whether the left local angle of attack value and the right local angle of attack value need to be corrected, wherein when the absolute value of the difference between the left local angle of attack value and the right local angle of attack value is less than or equal to a preset angle of attack difference threshold, the left local angle of attack value and the right local angle of attack value are not corrected, and wherein when the absolute value of the difference between the left local angle of attack value and the right local angle of attack value is greater than the angle of attack difference threshold, the method is corrected according to the calculation method of one aspect of the present invention. The method for calculating the angle of attack correction is used to calculate the angle of attack correction amount, and the angle of attack correction amount is used to correct the local angle of attack values ​​on the left and right sides; and step c, based on the spiking stall protection angle of attack value, the push-stick stall protection angle of attack value, the local angle of attack value on the left and right sides, the stall protection logic is executed. The stall protection logic includes spiking logic and push-stick logic. Specifically, when either the local angle of attack value on the left or the local angle of attack value on the right is greater than or equal to the spiking stall protection angle of attack value, the spiking logic is triggered. Specifically, when both the local angle of attack value on the left and the local angle of attack value on the right are less than the spiking stall protection angle of attack value, the spiking logic is not triggered. After the spiking logic is triggered on both sides, it is determined whether to trigger the push-stick logic: Specifically, when the average value of the local angle of attack value on the left and the local angle of attack value on the right is greater than or equal to the push-stick stall protection angle of attack value, the push-stick logic is triggered. Specifically, when the average value of the local angle of attack value on the left and the local angle of attack value on the right is less than the push-stick stall protection angle of attack value, the push-stick logic is not triggered.

[0018] A stall protection system according to the present invention includes a memory, a processor, and a computer program stored in the memory. The processor executes the computer program to implement the steps of a method for calculating angle of attack correction according to one aspect of the present invention, and / or the steps of a stall protection method according to one aspect of the present invention.

[0019] A stall protection system according to the present invention includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of a method according to one aspect of the present invention.

[0020] The stall protection method of this invention can effectively reduce errors caused by sideslip angle sensitivity and solve the problem of low measurement accuracy of sideslip angle sensors. The angle-of-attack correction logic architecture is simple and requires fewer signals for calculation, thus enabling rapid computation. Furthermore, compared to the sideslip angle signal from the sideslip angle sensor, the lateral overload signal from the corresponding sensor is more reliable, resulting in high system reliability. Attached Figure Description

[0021] To describe embodiments of the above and other features of the present invention, a more detailed description of the invention will be presented with reference to exemplary embodiments of the invention shown in the accompanying drawings. It is to be understood that these drawings depict only exemplary embodiments of the invention and should not be considered as limiting its scope; the invention will be described and explained using the drawings and with the aid of additional features and details. In the drawings:

[0022] Figure 1 This is a logic block diagram of a stall protection system according to an embodiment of the present invention;

[0023] Figure 2 It is based on Figure 1 The logic block diagram of the method for calculating the angle of attack correction of the stall protection system. Detailed Implementation

[0024] The terms “including,” “having,” “comprising,” and variations thereof, as used herein, are intended as open-ended transitional phrases, terms, or words that require the presence of a specified component / step, but also allow for the presence of other components / steps.

[0025] In this invention, unless explicitly stated otherwise, the terms “first,” “second,” etc., are not intended to indicate any difference in order, position, quantity, or importance, but are merely used as labels to distinguish different positions or steps, to differentiate one element, component, region, and / or step from another.

[0026] The present invention will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.

[0027] Figure 1 A logic block diagram of a stall protection system according to an embodiment of the present invention is shown schematically.

[0028] In a non-limiting example, the stall protection system of the present invention calculates the stick stall protection angle of attack αs and the push rod stall protection angle of attack α at step 10. P .

[0029] In step 11, the aircraft of the present invention senses parameters related to the aircraft's flight status through corresponding sensors, referred to herein as flight parameters, including but not limited to Mach number and aircraft configuration status, such as flap and slat positioning, icing conditions, and malfunctions.

[0030] In step 12, the main control processor of the aircraft of the present invention can calculate and obtain the corresponding stick jerking stall protection angle of attack αs and stick push stall protection angle of attack αs. P .

[0031] In a non-limiting example, the stall protection system of the present invention obtains the left local angle of attack value α at step 20. L and the local angle of attack value α on the right side R .

[0032] In step 21, the aircraft of the present invention also includes angle-of-attack sensors located on the left and right sides of the aircraft, and measures the local angle of attack on the left and the local angle of attack on the right by means of the angle-of-attack sensors.

[0033] In step 22, after preprocessing the signal about the angle of attack measured by the angle of attack sensor, the corresponding local left angle of attack value α can be calculated. L and the local angle of attack value α on the right side R .

[0034] The stall protection system according to the present invention obtains the left local angle of attack value α. L and the local angle of attack value α on the right side R Step 200 further includes: at step 203, determining whether it is necessary to correct the left local angle of attack value αL and the right local angle of attack value αR. The basis for this determination is the left local angle of attack value αL. L With the local angle of attack value α on the right side R The absolute value of the difference and the preset angle of attack difference threshold α lim A comparison.

[0035] When the local angle of attack on the left is α L With the local angle of attack value α on the right side R The absolute value of the difference is less than or equal to the angle of attack difference threshold α. lim At step 204, the local angle of attack value αL on the left and the local angle of attack value αR on the right are not corrected.

[0036] When the local angle of attack on the left is α L With the local angle of attack value α on the right side RThe absolute value of the difference is greater than the angle of attack difference threshold α. lim At step 26, the angle of attack correction Δα is applied. LOCAL The local angle of attack values ​​αL on the left and αR on the right are corrected.

[0037] In existing technologies, for example, the sideslip angle is used to correct the local angle of attack values ​​αL on the left and αR on the right. However, existing sideslip angle sensors have difficulty acquiring sideslip angle data, and the sampling rate and accuracy are low. Relying solely on flight parameter signal acquisition to trigger stall protection may reduce aircraft safety and could lead to pilot misjudgment.

[0038] In this invention, at step 25, the angle of attack correction Δα LOCAL Calculations are based on the lateral overload value Ny. This will be discussed in conjunction with the following text. Figure 2 Further describe the angle of attack correction Δα LOCAL The stall protection system according to the present invention corrects the left local angle of attack αL and the right local angle of attack αR based on the lateral overload value Ny. Compared with the sideslip angle sensor's sideslip angle signal, the corresponding sensor's lateral overload signal is more reliable, thus the system has high reliability.

[0039] Therefore, at step 27, the local angle of attack value α on the left side is obtained. L and the local angle of attack value α on the right side R For future use.

[0040] In a non-limiting example, the stall protection system according to the present invention may further include stall protection logic (stall alarm triggering) and deactivation logic.

[0041] At step 30, the stall protection system according to the invention can be based on the left local angle of attack value α calculated as follows. L and the local angle of attack value α on the right side R And as mentioned above, the angle of attack value αs for stick stall protection and the angle of attack value α for push rod stall protection. P This is used to execute the stall protection logic of the stall protection system. The stall protection logic may include lever jitter logic as shown in 31 and lever push logic as shown in 32.

[0042] In step 311, it is determined whether the stall protection logic's lever jitter logic has been triggered. When the angle of attack of the computer fuselage on either side reaches the stall protection lever jitter operating point after correction, the lever jitter logic is triggered, i.e., when the left-side local angle of attack value α... L and the local angle of attack value α on the right side R If any of the values ​​in the above are greater than or equal to the angle of attack value αs for stick derailment stall protection, the stick derailment logic is triggered at step 312, and when the left local angle of attack value αs is greater than or equal to the angle of attack value αs for stall protection, the stick derailment logic is triggered. L and the local angle of attack value α on the right side RWhen both are less than the angle of attack αs for stick stall protection, stick jitter logic is not triggered at step 313.

[0043] When both stall protection systems trigger lever jerking, in step 321, the average value method is used to determine whether the push lever logic for stall protection is triggered. When the left local angle of attack value α... L and the local angle of attack value α on the right side R The average value is greater than or equal to the pushrod stall protection angle of attack α. P At that time, the push rod logic is triggered at step 322, and when the left local angle of attack value α L and the local angle of attack value α on the right side R The average value is less than the pushrod stall protection angle of attack α. P At this time, the push-button logic is not triggered at step 323. However, if the stall protection logic of the stall protection system (both the lever jitter logic and / or push-button logic) is triggered, a stall warning will also be issued to the crew.

[0044] Release logic: The push rod release logic is that the push rod of the stall protection system is released when the corrected angle of attack of the computer body is less than the safe value of the working point of the stall protection push rod or the normal overload is less than 0.5g; the push rod release logic is that the stick release logic is released when the working angle of attack of the stall protection stick minus the corrected angle of attack of the computer body is greater than the safe value.

[0045] Figure 2 Schematic illustration Figure 1 The calculated angle of attack correction Δα for the stall protection system LOCAL The logic block diagram of the method is shown below. In step 25, the stall protection system according to the present invention can calculate the angle of attack correction Δα based on the lateral overload value Ny and various correction coefficients CY2, CY1, and CY0. LOCAL The angle of attack correction Δα is among them. LOCAL The formula is: Δα LOCAL =(CY2xNy 2 )+(CY1xNy 1 )+CY0, where Ny is the lateral overload value, and where CY2, CY1, and CY0 are preset quadratic correction coefficients CY2, linear correction coefficients CY1, and constant correction coefficients CY0.

[0046] In a non-limiting example, the stall protection system of the present invention calculates the lateral overload value Ny at step 40.

[0047] At step 41, the aircraft of the present invention also includes a corresponding lateral overload sensor for measuring the magnitude of the lateral overload of the aircraft.

[0048] In step 42, after processing the lateral overload signal measured by the corresponding sensor, the lateral overload value Ny can be calculated. Preferably, the signal processing specifically involves low-pass filtering to obtain the lateral overload value Ny.

[0049] Preferably, the stall protection system according to the present invention calculates the angle of attack correction Δα. LOCAL The process also includes: at step 43, determining whether the lateral overload value Ny needs to be corrected. This determination is based on the absolute value of the lateral overload value Ny and the preset lateral overload threshold value Ny. lim A comparison.

[0050] When the absolute value of the lateral overload value Ny is less than or equal to the preset lateral overload threshold value Ny lim At step 44, the lateral overload value Ny is not corrected.

[0051] When the absolute value of the lateral overload value Ny is greater than the lateral overload threshold value Ny lim At step 45, the lateral overload value Ny is corrected. Specifically, the sign of the lateral overload value Ny is maintained, and the absolute value of the lateral overload value Ny is equal to the lateral overload threshold value Ny. lim .

[0052] Therefore, at step 46, the lateral overload value Ny is obtained for use in step 25.

[0053] In a non-limiting example, the stall protection system of the present invention calculates the quadratic correction coefficient CY2, the first-order correction coefficient CY1, and the constant correction coefficient CY0 at step 50.

[0054] The correction coefficients CY2, CY1, and CY0 can be set based on at least one of the aforementioned aircraft state parameters.

[0055] In step 51, similar to step 11, the aircraft of the present invention senses parameters related to the aircraft's flight state through corresponding sensors, referred to herein as flight parameters, including but not limited to Mach number and aircraft configuration state, such as flap / slat positioning, icing conditions, and malfunction conditions. In step 52, the correction coefficients CY2, CY1, and CY0 can be set based on preset influence factors. In step 53, based on theoretical calculations and flight test data analysis, the influence factors of the correction coefficients CY2, CY1, and CY0 can be determined to include velocity pressure, weight, aerodynamic derivative, and center of gravity-related influence factors. Subsequently, considering each influence factor comprehensively and combining it with actual flight scenarios, the correction principle is determined. Based on flight test data, the correction formula, correction coefficients, and correction thresholds are determined. The correction curve is fitted mainly based on theoretical analysis combined with a large amount of data statistics, and the limit value under the normal operating envelope is determined as the correction threshold based on normal operating scenarios, thereby determining the correction logic.

[0056] Speed-pressure influence factor: Flight test data with the same configuration were selected, and the correction factor for this factor, considering the effect of speed, was basically the same (in aircraft design, different configurations may cause differences in this correction factor, mainly due to the significant differences in aerodynamic derivatives at different angles of attack). From an engineering perspective, this correction factor for the aircraft decreases with increasing speed under different conditions, and is approximately inversely proportional to the square of the speed. At the same speed, even at different altitudes, this correction factor remains essentially the same.

[0057] Weight Influence Factor: Under otherwise identical conditions, this correction factor is basically proportional to the flight weight, and it generally increases with the increase of flight weight. By statistically calculating the percentage influence of this factor on the correction factor, if its influence is relatively large compared to other factors, a weight factor can be introduced into the correction formula. Specifically, this differentiates the correction factors for large, medium, and small weights.

[0058] Landing gear influence factor (aerodynamic derivative-related influence factor): Considering the positional relationship of the landing gear relative to the center of gravity, its impact on the aerodynamic derivative is analyzed. An increase in the absolute value of the aerodynamic derivative will decrease the absolute value of this correction factor. By statistically calculating the percentage influence of this factor on the correction factor, if its influence is relatively large compared to other factors, the landing gear factor can be introduced into the correction formula. Specifically, the correction factor can be differentiated between landing gear retracted and extended configurations.

[0059] Center of gravity influence factor: At the same sideslip angle, a forward shift of the center of gravity increases the rudder deflection required to maintain the sideslip angle, thereby reducing lateral overload and subsequently increasing this correction factor. The influence of the forward and aft centers of gravity on this correction factor is confirmed through flight test data analysis and theoretical calculations. By statistically calculating the percentage influence of this factor on the correction factor, if its influence is relatively large compared to other factors, the center of gravity factor can be introduced into the correction formula, specifically distinguishing the correction factors for forward and aft centers of gravity.

[0060] Subsequently, at step 25, the stall protection system according to the invention can calculate the angle of attack correction Δα based on the calculated lateral overload value Ny and the aforementioned correction coefficients CY2, CY1, and CY0. LOCAL .

[0061] Preferably, the angle of attack correction Δα is calculated. LOCAL The steps may also include: at step 2501, determining whether the lateral overload value Ny needs to be corrected. The basis for this determination is the left-side local angle of attack value α. L With the local angle of attack value α on the right side R Comparison between the difference and 0.

[0062] When the local angle of attack on the left is α L Subtract the local angle of attack value α on the right side R When the difference is greater than 0, in step 2502, it is further determined whether the lateral overload value Ny needs to be corrected. The basis for this determination is the comparison between the lateral overload value Ny and 0. If the lateral overload value Ny is less than 0, then in step 2504, the lateral overload value Ny is corrected, specifically, the lateral overload value Ny is set to 0. And if the lateral overload value Ny is greater than or equal to 0, then in step 2505, the lateral overload value Ny is not corrected.

[0063] When the local angle of attack on the left is α L Subtract the local angle of attack value α on the right side R When the difference is less than or equal to 0, in step 2503, it is further determined whether the lateral overload value Ny needs to be corrected. The basis for this determination is the comparison between the lateral overload value Ny and 0. If the lateral overload value Ny is less than or equal to 0, then in step 2506, the lateral overload value Ny is not corrected. And if the lateral overload value Ny is greater than 0, then in step 2507, the lateral overload value Ny is corrected, specifically, the lateral overload value Ny is set to 0.

[0064] The lateral overload value Ny is thus obtained for use in step 2508. In step 2508, the angle of attack correction Δα can be calculated using the aforementioned formula. LOCAL The angle-of-attack correction Δα is calculated based on the lateral overload value Ny and various correction coefficients CY2, CY1, and CY0. LOCAL.

[0065] Preferably, the angle of attack correction Δα is calculated. LOCAL The steps may also include: at step 2509, determining whether the lateral overload value Ny needs to be corrected using a median limit. The basis for this determination is the angle-of-attack correction amount Δα. LOCAL The comparison between the absolute value and the first absolute value, where α is defined by the local angle of attack value on the left. L Or the local angle of attack value α on the right side R Subtract the local angle of attack value α on the left side L With the local angle of attack value α on the right side R The absolute value of the difference obtained from the average is... Let it be the first absolute value.

[0066] When the angle of attack correction Δα LOCAL When the absolute value is less than or equal to the first absolute value, at step 2510, the angle of attack correction Δα is not applied. LOCAL Make corrections.

[0067] When the angle of attack correction Δα LOCAL When the absolute value is greater than the first absolute value, at step 2511, the angle of attack correction Δα is adjusted. LOCAL Make corrections while maintaining the angle of attack correction amount Δα. LOCAL The sign and correction result in the angle of attack correction amount Δα. LOCAL The absolute value of is equal to the first absolute value.

[0068] Therefore, at step 2512, the angle of attack correction Δα is obtained. LOCAL This is for use in subsequent steps. Afterwards, you can return to... Figure 1 Step 25 in the diagram represents the subsequent steps of the stall protection method.

[0069] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention have been clearly and completely described above in conjunction with the specific embodiments and accompanying drawings.

[0070] It should be understood that the steps shown above in conjunction with specific embodiments are illustrative. Those skilled in the art can add or delete corresponding steps, adjust the execution order of one or more steps, or replace one or more steps with similar steps.

[0071] Although various embodiments have been described above, it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of them, and are presented by way of example rather than limitation. It will be apparent to those skilled in the art that the disclosed subject matter may be implemented in other specific forms without departing from its spirit and essential characteristics.

[0072] In this process, various elements important to the present invention or elements conducive to further development of the present invention will be mentioned in the specific examples. However, some of these elements may also be used to further develop the present invention when departing from the content and other features of the corresponding examples. Therefore, the embodiments described above are considered exemplary in all respects and not restrictive, and are not intended to limit the present invention in any way.

[0073] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. This disclosure also includes various modifications and equivalent variations. In addition, various combinations and methods, further including only one element, one or more or less other combinations and methods, also fall within the scope and concept of this disclosure.

Claims

1. A method of calculating a correction to an angle of attack for a stall protection system of an aircraft, characterized in that, The method comprises: In the first step, it is determined whether the lateral overload value (Ny) needs to be corrected on the basis of the left local angle of attack value (a L ), the right local angle of attack value (a R ) and the lateral overload value (Ny), wherein, when the difference between the left local angle of attack value (a L ) minus the right local angle of attack value (a R ) is greater than 0, If the lateral overload value (Ny) is greater than or equal to 0, the lateral overload value (Ny) is not corrected, and If the lateral overload value (Ny) is less than 0, the lateral overload value (Ny) is corrected, specifically, the lateral overload value (Ny) is set to 0, and wherein, when a difference between the left local angle of attack value (a L ) minus the right local angle of attack value (a R ) is less than or equal to 0, If the lateral overload value (Ny) is less than or equal to 0, the lateral overload value (Ny) is not corrected, and If the lateral overload value (Ny) is greater than 0, the lateral overload value (Ny) is corrected, specifically, the lateral overload value (Ny) is set to 0. - a second step of calculating said angle of attack correction (Δα LOCAL ) on the basis of said lateral overload value (Ny), in particular by using a first formula based on said lateral overload value (Ny), LOCAL ) on the basis of said lateral overload value (Ny), in particular by using a first formula based on said lateral overload value (Ny), wherein the first formula is Δα LOCAL = (CY2xNy 2 )+(CY1xNy 1 )+CY0, CY2, CY1, CY0 are preset quadratic correction coefficients (CY2), linear correction coefficients (CY1) and constant correction coefficients (CY0).

2. The method of claim 1, wherein, The method of calculating the angle of attack correction further comprises a third step of determining whether the angle of attack correction (Δα LOCAL ) needs to be corrected, First, an absolute value of a difference between the left local angle of attack value (a L ) or the right local angle of attack value (a R ) and an average of the left local angle of attack value (a L ) and the right local angle of attack value (a R ) is taken as a first absolute value, and wherein, when the absolute value of the angle-of-attack correction amount (Δα LOCAL ) is smaller than or equal to the first absolute value, the angle-of-attack correction amount (Δα LOCAL ) is not corrected, and when the absolute value of the angle-of-attack correction amount (Δα LOCAL ) is larger than the first absolute value, the angle-of-attack correction amount (Δα LOCAL ) is corrected. wherein, when the absolute value of the angle of attack correction amount (Δα LOCAL ) is greater than the first absolute value, the angle of attack correction amount (Δα LOCAL ) is corrected, the sign of the angle of attack correction amount (Δα LOCAL ) is maintained and the angle of attack correction amount (Δα LOCAL ) is corrected such that the absolute value of the angle of attack correction amount (Δα LOCAL ) is equal to the first absolute value.

3. The method of claim 1, wherein, In the first step, the lateral overload of the aircraft is sensed by a corresponding sensor, and the signal of the corresponding sensor is processed, specifically, low-pass filtering is performed, to obtain the lateral overload value (Ny).

4. The method of claim 1, wherein, In the first step, it is judged whether the lateral overload value (Ny) needs to be corrected, wherein, when the absolute value of the lateral overload value (Ny) is less than or equal to a preset lateral overload threshold value (Ny lim ), the lateral overload value (Ny) is not corrected, and when the absolute value of the lateral overload value (Ny) is greater than the preset lateral overload threshold value (Ny lim ), the lateral overload value (Ny) is corrected. wherein, when the absolute value of said lateral overload value (Ny) is greater than said lateral overload threshold value (Ny lim ), said lateral overload value (Ny) is corrected, maintaining the sign of said lateral overload value (Ny) and correcting such that the absolute value of said lateral overload value (Ny) is equal to said lateral overload threshold value (Ny lim ).

5. The method of claim 1, wherein, In the second step, the quadratic correction coefficients (CY2), the linear correction coefficients (CY1) and the constant correction coefficients (CY0) are calculated based on flight parameters and influence factors, wherein the influence factors include speed, weight, aerodynamic derivatives, center of gravity, and the flight parameters are sensed by corresponding sensors, and The flight parameters include Mach number, flap slot locking, icing conditions, fault conditions, and the flight parameters are preset.

6. A method of stall protection for a stall protection system, characterized in that The stall protection method comprises: a step of sensing flight parameters of the aircraft with corresponding sensors and calculating a stick shaker stall protection angle of attack value (as) and a pusher stall protection angle of attack value (a P ), based on the flight parameters, wherein the flight parameters include Mach number, slat track, icing conditions, failure conditions; b step, sensing the left local angle of attack and the right local angle of attack of the aircraft with corresponding sensors and processing the signals of the corresponding sensors to obtain a left local angle of attack value (a L ) and a right local angle of attack value (a R ), and determining whether a correction of the left local angle of attack value (a L ) and the right local angle of attack value (a R ) is required, wherein, when an absolute value of a difference between the left local angle of attack value (a L ) minus the right local angle of attack value (a R ) is less than or equal to a preset angle of attack difference threshold value (a lim ), the left local angle of attack value (a L ) and the right local angle of attack value (a R ) are not corrected, and wherein, when an absolute value of a difference between the left local angle of attack value (a L ) minus the right local angle of attack value (a R ) is greater than the angle of attack difference threshold value (a lim ), the angle of attack correction amount (Da LOCAL ) is calculated according to the method of any one of claims 1-5, and the left local angle of attack value (a L ) and the right local angle of attack value (a R ) are corrected by the angle of attack correction amount (Da LOCAL ); and c. performing stall protection logic based on the stick shaker stall protection angle of attack value (as), the pusher stall protection angle of attack value (a P ), the left local angle of attack value (a L ), and the right local angle of attack value (a R ), the stall protection logic including stick shaker logic and pusher logic wherein the stick logic is triggered when either the left local angle of attack value (a L ) and the right local angle of attack value (a R ) is greater than or equal to the stick stall protection angle of attack value (as), wherein the stick logic is not triggered when both the left local angle of attack value (a L ) and the right local angle of attack value (a R ) are less than the stick stall protection angle of attack value (as), and When both sides trigger the stick-shaking logic, it is judged whether the push-stick logic is triggered: wherein the pushrod logic is triggered when the average of the left local angle of attack value (a L ) and the right local angle of attack value (a R ) is greater than or equal to the pushrod stall protection angle of attack value (a P ), and wherein the pushrod logic is not triggered when the average of the left local angle of attack value (a L ) and the right local angle of attack value (a R ) is less than the pushrod stall protection angle of attack value (a P ).

7. A stall protection system comprising a memory, a processor and a computer program stored on the memory, wherein, The processor executes the computer program to implement the steps of the method of claim 1-5, and / or the steps of the stall protection method of claim 6.

Images