Method for controlling throat area during engine nozzle throat area measurement failure

Abstract

The invention belongs to the technical field of engine nozzle throat area control, and relates to a method for controlling the throat area during engine nozzle throat area measurement failure, which comprises the following steps of: 1, based on an engine control rule, determining a corresponding relation between a low-pressure conversion rotating speed and a nozzle throat area given value at different air inlet temperatures; 2, based on an engine test result, the corresponding relation between the low-pressure conversion rotating speed and the high-pressure conversion rotating speed under different nozzle throat areas is determined; step 3, when engine nozzle throat area measurement fails, obtaining a current nozzle throat area according to a current low-pressure conversion rotating speed, a high-pressure conversion rotating speed and a corresponding relation between the low-pressure conversion rotating speed and the high-pressure conversion rotating speed based on different nozzle throat areas, and obtaining a current nozzle throat area according to the current low-pressure conversion rotating speed and the air inlet temperature; based on the corresponding relation between the low-pressure conversion rotating speed and the given value of the throat area of the spray pipe at different air inlet temperatures, the given value of the throat area of the spray pipe is obtained, and closed-loop control is conducted on the throat area of the spray pipe.

Description

Technical Field

[0001] The present application belongs to the technical field of engine nozzle throat area control design, and specifically relates to a method for controlling the engine nozzle throat area when a throat area measurement failure occurs. Background Art

[0002] Engines with adjustable nozzle throat area, such as twin-rotor turbofan engines, usually control the nozzle throat area through an actuator.

[0003] There is a one-to-one correspondence between the displacement of the actuator and the nozzle throat area. After the engine is assembled, the size of the nozzle throat area is usually determined by calibrating the displacement of the actuator. When the engine is working, the displacement of the actuator is measured by a linear displacement sensor installed on the actuator, and the nozzle throat area is then obtained.

[0004] The linear displacement sensor installed on the actuator is prone to malfunction after long-term use. It can no longer measure the displacement of the actuator and obtain the nozzle throat area, resulting in nozzle throat area measurement failure, and therefore, it is impossible to achieve accurate control of the nozzle throat area.

[0005] At present, when a linear displacement sensor installed on the actuator fails, the nozzle throat area is mostly controlled by comparing the given value of the nozzle throat area with the demarcation value, wherein the given value of the nozzle throat area is an expected value based on the engine control law, and the demarcation value of the nozzle throat area is a fixed value selected between the maximum control area and the minimum control area of ​​the nozzle throat. When the given value of the nozzle throat area is greater than the demarcation value, the nozzle throat area is controlled to the maximum value, and when the given value of the nozzle throat area is less than the demarcation value, the nozzle throat area is controlled to the minimum value. This technical solution has the following defects: When there is a failure in the measurement of the nozzle throat area, based on the comparison between the given value of the nozzle throat area and the delimiter value, the nozzle throat area is simply controlled to the maximum value or minimum value, which may easily cause the nozzle throat area to be significantly greater than or less than the given value of the nozzle throat area, causing changes in the matching of the entire engine. When the nozzle throat area is controlled to the maximum value, the fan working line will usually move down, greatly reducing the engine thrust. When the nozzle throat area is controlled to the minimum value, the fan working line will usually move up, greatly reducing the stability of the engine and causing a significant increase in the engine exhaust temperature.

[0006] This application is proposed in view of the above-mentioned technical defects. Summary of the invention

[0007] The purpose of the present application is to provide a method for controlling the throat area of ​​an engine nozzle when a measurement failure of the throat area occurs, so as to overcome or alleviate at least one of the known technical defects.

[0008] The technical solution of this application is: A method for controlling the throat area of ​​an engine nozzle when a throat area measurement failure occurs, comprising: Step 1: Based on the engine control law, determine the corresponding relationship between the low-pressure converted speed and the given value of the nozzle throat area at different intake temperatures; Step 2: Based on the engine test results, determine the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas; Step three, when there is a failure in measuring the engine nozzle throat area, the current low-pressure converted speed and high-pressure converted speed are used, and based on the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed at different nozzle throat areas, the current nozzle throat area is obtained. Also, the current low-pressure converted speed and intake temperature are used, and based on the corresponding relationship between the low-pressure converted speed and the given value of the nozzle throat area at different intake temperatures, the given value of the nozzle throat area is obtained, and closed-loop control of the nozzle throat area is performed.

[0009] According to at least one embodiment of the present application, in the above-mentioned method for controlling the throat area of ​​the engine nozzle throat when the measurement failure occurs, the range of the low-pressure converted speed is set to the low-pressure converted speed of the engine from the slow state to the intermediate state.

[0010] According to at least one embodiment of the present application, in the above-mentioned method for controlling the throat area when a measurement failure occurs in the engine nozzle throat area, in step two, the correspondence between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas is determined specifically based on the engine high-altitude platform test results.

[0011] According to at least one embodiment of the present application, in the above-mentioned method for controlling the throat area of ​​the engine nozzle throat area when a measurement failure occurs, in step two, the correspondence between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas is determined specifically based on the engine simulation test results.

[0012] According to at least one embodiment of the present application, in the above-mentioned method for controlling the throat area of ​​the engine nozzle when the throat area measurement fails, in step three, the nozzle throat area is closed-loop controlled, specifically: Calculate the deviation between the current nozzle throat area and the given value of the nozzle throat area ,in, is the given value of the nozzle throat area; is the current nozzle throat area; The control current is calculated by the PI control algorithm ,in, is the proportional control parameter, which is a constant; The balance current of the electro-hydraulic servo valve of the actuator is a constant; is the integral control parameter, which is a constant; For the points link; Will control the current The output is given to the actuator electro-hydraulic servo valve to control the actuator and adjust the nozzle throat area so that the deviation Δ between the current nozzle throat area and the given value of the nozzle throat area tends to 0.

[0013] This application has at least the following beneficial technical effects: Provided is a method for controlling the nozzle throat area when a nozzle throat area measurement failure occurs. When the nozzle throat area measurement failure occurs, based on slip limit, the current low-pressure conversion speed and high-pressure conversion speed are used, and based on the corresponding relationship between the low-pressure conversion speed and the high-pressure conversion speed under different nozzle throat areas, the current nozzle throat area is obtained, and the current low-pressure conversion speed and intake temperature are used to obtain a given value of the nozzle throat area. The nozzle throat area is closed-loop controlled, and the nozzle throat area can be controlled to be close to the given value, so that the nozzle throat area and the whole machine matching are close to the design state, thereby realizing effective control of the nozzle throat area. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic diagram of a method for controlling the throat area of ​​an engine nozzle when a throat area measurement failure occurs, provided in an embodiment of the present application; Figure 2 It is a control logic diagram for closed-loop control of the nozzle throat area provided in an embodiment of the present application.

[0015] In order to better illustrate the present embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. In addition, the drawings are only used for illustrative purposes and should not be construed as limitations on the present application. DETAILED DESCRIPTION

[0016] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be described in further detail in detail and in detail with reference to the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design.

[0017] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application shall have the usual meanings understood by those of ordinary skill in the art to which this application belongs. The words used in the description of this application to indicate orientation are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "include" used in the description of this application indicates that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, but does not exclude other elements or objects.

[0018] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installation", "connection" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Technical personnel in the field can understand its specific meaning in this application according to the specific circumstances.

[0019] The engine slip is usually related to the fan inlet adjustable guide vane angle, the compressor adjustable guide vane angle and the nozzle throat area. When the fan inlet adjustable guide vane angle and the compressor adjustable guide vane angle are determined, the engine slip is only related to the nozzle throat area.

[0020] In the engine control law, the fan inlet adjustable guide vane angle is usually designed to change with the low-pressure converted speed, the compressor adjustable guide vane angle changes with the high-pressure converted speed, and the nozzle throat area changes with the engine's intake temperature and low-pressure converted speed. When the low-pressure converted speed is a constant, the high-pressure converted speed will change with the change of the engine's intake temperature. Therefore, when the nozzle throat area and the low-pressure converted speed are determined, the engine's slip is determined accordingly. Conversely, when the engine's slip and low-pressure converted speed are determined, the nozzle throat area is also determined accordingly.

[0021] Based on the above, the present application provides a method for controlling the throat area of ​​an engine nozzle when a throat area measurement failure occurs, such as Figure 1 shown.

[0022] Step 1: Based on the engine control law, determine the corresponding relationship between the low-pressure converted speed and the given value of the nozzle throat area at different intake temperatures.

[0023] The range of the low-pressure converted speed can be set to the low-pressure converted speed of the engine from an idle state to an intermediate state.

[0024] The corresponding relationship between the low pressure conversion speed and the given value of the nozzle throat area at different inlet temperatures can be listed as follows: Step 2: Based on the engine test results, determine the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas.

[0025] Specifically, the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas can be determined based on the engine high-altitude test results or simulation test results.

[0026] The corresponding relationship between the low-pressure conversion speed and the high-pressure conversion speed under different nozzle throat areas can be listed as follows: Step three, when there is a failure in measuring the engine nozzle throat area, the current low-pressure converted speed and high-pressure converted speed are used, and based on the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed at different nozzle throat areas, the current nozzle throat area is obtained. Also, the current low-pressure converted speed and intake temperature are used, and based on the corresponding relationship between the low-pressure converted speed and the given value of the nozzle throat area at different intake temperatures, the given value of the nozzle throat area is obtained, and closed-loop control of the nozzle throat area is performed.

[0027] The nozzle throat area is closed-loop controlled, and the control logic is as follows: Figure 2 For details, please refer to the following: Calculate the deviation between the current nozzle throat area and the given value of the nozzle throat area ,in, is the given value of the nozzle throat area; is the current nozzle throat area; The control current is calculated by the PI control algorithm ,in, is the proportional control parameter, which is a constant; The balance current of the electro-hydraulic servo valve of the actuator is a constant; is the integral control parameter, which is a constant; For the points link; Will control the current The output is given to the actuator electro-hydraulic servo valve to control the actuator and adjust the nozzle throat area so that the deviation Δ between the current nozzle throat area and the given value of the nozzle throat area tends to 0.

[0028] The above-mentioned embodiment discloses a method for controlling the nozzle throat area when a fault occurs in the nozzle throat area measurement. When a fault occurs in the nozzle throat area measurement, based on the slip limit, the current low-pressure converted speed and high-pressure converted speed are used, and based on the correspondence between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas, the current nozzle throat area is obtained, and the current low-pressure converted speed and intake temperature are used to obtain a given value of the nozzle throat area. The nozzle throat area is closed-loop controlled, and the nozzle throat area can be controlled to be close to the given value, so that the nozzle throat area and the whole machine matching are close to the design state, thereby achieving effective control of the nozzle throat area.

[0029] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the scope of protection of the present application.

Claims

1. A method for controlling the throat area of ​​an engine nozzle when there is a measurement failure of the throat area, characterized in that: include: Step 1: Based on the engine control law, determine the corresponding relationship between the low-pressure converted speed and the given value of the nozzle throat area at different intake temperatures; Step 2: Based on the engine test results, determine the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas; Step three, when there is a failure in measuring the engine nozzle throat area, the current low-pressure converted speed and high-pressure converted speed are used, and based on the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed at different nozzle throat areas, the current nozzle throat area is obtained. Also, the current low-pressure converted speed and intake temperature are used, and based on the corresponding relationship between the low-pressure converted speed and the given value of the nozzle throat area at different intake temperatures, the given value of the nozzle throat area is obtained, and closed-loop control of the nozzle throat area is performed.

2. The method for controlling the throat area of ​​an engine nozzle when there is a measurement failure of the throat area of ​​the engine nozzle according to claim 1, characterized in that: The range of the low-pressure converted speed is set to the low-pressure converted speed of the engine from the idling state to the intermediate state.

3. The method for controlling the throat area of ​​an engine nozzle when there is a measurement failure of the throat area of ​​the engine nozzle according to claim 1, characterized in that: In step 2, based on the engine high-altitude test results, the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas is determined.

4. The method for controlling the throat area of ​​an engine nozzle when there is a measurement failure of the throat area of ​​the engine nozzle according to claim 1, characterized in that: In step 2, based on the engine simulation test results, the corresponding relationship between the low-pressure converted speed and the high-pressure converted speed under different nozzle throat areas is determined.

5. The method for controlling the throat area of ​​an engine nozzle when there is a measurement failure of the throat area of ​​the engine nozzle according to claim 1, characterized in that: In step 3, the nozzle throat area is closed-loop controlled, specifically: Calculate the deviation between the current nozzle throat area and the given value of the nozzle throat area ,in, is the given value of the nozzle throat area; is the current nozzle throat area; The control current is calculated by the PI control algorithm ,in, is the proportional control parameter, which is a constant; The balance current of the electro-hydraulic servo valve of the actuator is a constant; is the integral control parameter, which is a constant; For the points link; Will control the current The output is given to the actuator electro-hydraulic servo valve to control the actuator and adjust the nozzle throat area so that the deviation Δ between the current nozzle throat area and the given value of the nozzle throat area tends to 0.

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