A fuel supply control method and device for judging fuel supply abnormality based on speed increase rate

Abstract

This application belongs to the field of engine control technology and relates to a fuel supply control method and device for determining fuel supply anomalies based on the speed increase rate. The method comprises: step S1, determining the type of engine fuel supply anomaly based on the engine fuel supply set value and the speed increase rate; step S2, when the engine acceleration is abnormal, selecting the maximum value of the fuel supply given by the engine acceleration fuel supply rule and the fuel supply in the engine idling state as the engine fuel supply set value; when the engine deceleration is abnormal, when the engine speed is less than the speed set value or the exhaust temperature is less than the temperature set value, correcting the fuel supply given by the engine deceleration fuel supply rule based on a correction coefficient to obtain the engine fuel supply set value; conversely, using the fuel supply in the engine idling state as the engine fuel supply set value; and step S3, controlling the fuel supply of an aircraft engine based on the engine fuel supply set value. This application avoids engine overheating and overspeeding.

Description

Technical Field

[0001] The present application belongs to the field of engine control technology, and in particular relates to a fuel supply control method and device for judging fuel supply abnormality based on the speed increase rate. Background Art

[0002] The fuel supply to the main combustion chamber of an aircraft engine is mainly affected by the intake air flow rate, total intake air temperature, etc. For engines equipped with digital electronic controllers, there may be problems with abnormal fuel supply to the engine when there are failures in the measurement of characteristic parameters such as intake air flow rate and total intake air temperature, and when there are serious deviations in the measurement results.

[0003] Due to the wide operating envelope and complex operating conditions of aircraft engines, strict fault judgment criteria for parameters such as intake flow rate and total intake temperature must be set to avoid misjudgments. This inevitably leads to missed judgments in some cases. If users fail to promptly address these missed judgments, serious consequences such as overheating and overspeed may occur. Summary of the Invention

[0004] In order to solve the above problems, the present application provides a fuel supply control method and device for judging fuel supply abnormality based on the speed increase rate, so as to accurately judge whether the measurement parameters have failed and avoid abnormal backup problems caused by misjudgment.

[0005] In a first aspect, the present application provides a fuel supply control method for determining fuel supply abnormality based on a speed increase rate, which mainly includes:

[0006] Step S1, determining the type of abnormal engine fuel supply according to the engine fuel supply setting value and the speed increase rate;

[0007] Step S2: When the engine fuel supply abnormality is acceleration abnormality, the maximum value of the fuel supply amount given by the engine acceleration fuel supply rule and the fuel supply amount in the engine idling state is selected as the engine fuel supply amount set value. When the engine fuel supply abnormality is deceleration abnormality, the engine fuel supply amount set value is calculated by the following method:

[0008] When the engine speed is less than the speed setting value or the exhaust temperature is less than the temperature setting value, the fuel supply amount given by the engine deceleration fuel supply law is corrected based on the correction coefficient to obtain the engine fuel supply amount setting value; conversely, the fuel supply amount in the engine idling state is used as the engine fuel supply amount setting value;

[0009] Step S3: Controlling the fuel supply of the aircraft engine based on the given value of the engine fuel supply amount.

[0010] Preferably, step S1 further comprises:

[0011] Step S11: Obtain the engine fuel supply set value and the engine speed rising rate. The engine fuel supply set value includes acceleration fuel supply and deceleration fuel supply, and the engine speed rising rate includes positive and negative values.

[0012] Step S12: When the engine fuel supply set value is acceleration fuel supply and the engine speed rising rate is negative, determine that the engine fuel supply abnormal type is acceleration abnormality; when the engine fuel supply set value is deceleration fuel supply and the engine speed rising rate is positive, determine that the engine fuel supply abnormal type is deceleration abnormality.

[0013] Preferably, step S2 further includes:

[0014] Step S21: Determine the speed correction coefficient kdec_n according to the engine speed n:

[0015] kdec_n = a - (1 - a)(n - ndem - detn) / detn;

[0016] Where, a is the maximum acceleration fuel coefficient to ensure that the engine does not accelerate, 0 < a < 1, ndem is the speed control planned value, detn is the speed overshoot limit value, and the sum of ndem and detn is the speed set value;

[0017] Step S22: Determine the temperature correction coefficient kdec_T according to the exhaust gas temperature T: ​​​​​​​​​​​​​​​​​​​​​

[0025] The engine fuel supply set value calculation module is used to select the maximum value between the fuel supply given by the engine acceleration fuel supply law and the fuel supply in the engine idle state as the engine fuel supply set value when the engine fuel supply abnormal type is acceleration abnormality. When the engine fuel supply abnormal type is deceleration abnormality, the engine fuel supply set value is calculated by the following method:

[0026] When the engine speed is less than the speed set value or the exhaust gas temperature is less than the temperature set value, the fuel supply given by the engine deceleration fuel supply law is corrected based on the correction coefficient to obtain the engine fuel supply set value. Otherwise, the fuel supply in the engine idle state is used as the engine fuel supply set value;

[0027] The fuel supply control module is used to control the fuel supply of the aero-engine based on the engine fuel supply set value.

[0028] Preferably, the engine fuel supply abnormal type determination module further includes:

[0029] The speed rise rate acquisition unit is used to acquire the engine fuel supply set value and the speed rise rate. The engine fuel supply set value includes acceleration fuel supply and deceleration fuel supply, and the speed rise rate includes positive and negative values;

[0030] The abnormal type judgment unit is used to determine that the engine fuel supply abnormal type is acceleration abnormality when the engine fuel supply set value is acceleration fuel supply and the speed rise rate is negative; and to determine that the engine fuel supply abnormal type is deceleration abnormality when the engine fuel supply set value is deceleration fuel supply and the speed rise rate is positive.

[0031] Preferably, the engine fuel supply set value calculation module includes:

[0032] The speed correction coefficient calculation unit is used to determine the speed correction coefficient kdec_n according to the engine speed n:

[0033] kdec_n = a - (1 - a)(n - ndem - detn) / detn;

[0034] Where, a is the maximum acceleration fuel coefficient to ensure that the engine does not accelerate, 0 < a < 1, ndem is the speed control planned value, detn is the speed overshoot limit value, and the sum of ndem and detn is the speed set value;

[0035] The temperature correction coefficient calculation unit is used to determine the temperature correction coefficient kdec_T according to the exhaust gas temperature T:

[0036] kdec_T = a - (1 - a)(T - Tdem - detT) / detT;

[0037] Among them, Tdem is the temperature control plan value, detT is the temperature overshoot limit value, and the sum of Tdem and detT is the temperature set value;

[0038] The correction coefficient selection unit is used to select the smaller value of the speed correction coefficient kdec_n and the temperature correction coefficient kdec_T as the correction coefficient k_wfmdec to correct the fuel supply amount given by the engine deceleration fuel supply law.

[0039] Preferably, the oil supply control device further comprises:

[0040] The time limit module is used to determine the duration of the engine fuel supply abnormality. When the duration of the engine fuel supply abnormality exceeds the set value, the engine fuel supply is switched to backup control or a fixed fuel supply amount is set for fuel supply control.

[0041] This application can effectively identify and handle abnormal fuel supply problems caused by abnormal parameter measurement within the full engine envelope, thereby avoiding engine overheating and overspeeding. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flowchart of a preferred embodiment of the fuel supply control method of the present application for determining fuel supply abnormality based on the speed increase rate. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the implementation of this application will be described in more detail below in conjunction with the drawings in the implementation of this application. In the drawings, the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions. The described implementation is a part of the implementation of this application, not all of the implementations. The implementation described below with reference to the drawings is exemplary and is intended to be used to explain this application, and should not be understood as a limitation on this application. Based on the implementation in this application, all other implementations obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The implementation of this application is described in detail below in conjunction with the drawings.

[0044] The first aspect of the present application provides a fuel supply control method based on the speed increase rate to determine the fuel supply abnormality, such as Figure 1 As shown, it mainly includes:

[0045] Step S1, determining the type of abnormal engine fuel supply according to the engine fuel supply setting value and the speed increase rate;

[0046] Step S2: When the engine fuel supply abnormality is acceleration abnormality, the maximum value of the fuel supply amount given by the engine acceleration fuel supply rule and the fuel supply amount in the engine idling state is selected as the engine fuel supply amount set value. When the engine fuel supply abnormality is deceleration abnormality, the engine fuel supply amount set value is calculated by the following method:

[0047] When the engine speed is less than the speed setting value or the exhaust temperature is less than the temperature setting value, the fuel supply amount given by the engine deceleration fuel supply law is corrected based on the correction coefficient to obtain the engine fuel supply amount setting value; conversely, the fuel supply amount in the engine idling state is used as the engine fuel supply amount setting value;

[0048] Step S3: Controlling the fuel supply of the aircraft engine based on the given value of the engine fuel supply amount.

[0049] Under normal circumstances, the setting of the engine acceleration / deceleration fuel supply can ensure that the engine accelerates / decelerates. When there is a significant fuel supply anomaly due to the measurement parameters, the engine will still decelerate when the fuel supply is accelerated, or accelerate when the fuel supply is decelerated. The acceleration and deceleration of the engine can be determined by the speed increase rate. Therefore, in step S1, the present application can determine whether there is a fuel supply anomaly based on the speed increase rate.

[0050] In some optional embodiments, step S1 further includes:

[0051] Step S11, obtaining an engine fuel supply setting value and a speed increase rate, wherein the engine fuel supply setting value includes acceleration fuel supply and deceleration fuel supply, and the speed increase rate includes positive and negative values;

[0052] Step S12: When the engine fuel supply setting value is acceleration fuel supply and the speed increase rate is a negative value, the engine fuel supply abnormality type is determined to be acceleration abnormality; when the engine fuel supply setting value is deceleration fuel supply and the speed increase rate is a positive value, the engine fuel supply abnormality type is determined to be deceleration abnormality.

[0053] Step S2 is used to handle the two aforementioned anomalies separately. When the engine fuel supply anomaly is acceleration anomaly, the engine is set to accelerate fuel supply, but the speed increase rate ndot is less than 0. In this case, the measurement parameter failure manifests as a sudden step decrease, which may cause the engine to decelerate abnormally and even reverse. Therefore, within the confirmation time, it is necessary to add the logic of "ensuring that the fuel supply is not less than the idle fuel volume", which can be expressed as follows:

[0054] wfDem=max(wf 慢车 ,wfaccDem);

[0055] Among them, wfDem is the given value of engine fuel supply, wfaccDem is the fuel supply given by the engine acceleration fuel supply law, wf 慢车 The fuel supply for the engine at idle speed.

[0056] When the engine fuel supply abnormality type is deceleration abnormality, that is, the engine is set to decelerate fuel supply, but the speed increase rate ndot>0, the measurement parameter failure is manifested as a sudden step increase, which may cause the engine to accelerate abnormally and overspeed. Therefore, it is necessary to increase the handling logic: when the control plan is exceeded by a certain amount, the fuel supply coefficient is appropriately reduced. When it reaches a level close to overspeed, it is directly set to the slow speed fuel amount to avoid overspeed. The exceeding of the control plan by a certain amount here can be expressed using speed and exhaust temperature, that is:

[0057] Control plan value ndem≤speed n≤control plan value ndem+overshoot limit value detn; here, control plan value ndem+overshoot limit value detn is the speed setting value of step S2; control plan value Tdem≤exhaust temperature T≤control plan value Tdem+overshoot limit value detT; here, control plan value Tdem+overshoot limit value detT is the temperature setting value of step S2.

[0058] When the above two conditions are met at the same time, the fuel supply coefficient is appropriately reduced, that is, the fuel supply given by the engine deceleration fuel supply law is corrected by a correction coefficient less than 1. If the above limit is exceeded, it is directly set to the slow speed fuel quantity, that is, when the speed n> speed setting value or the exhaust temperature T> temperature setting value, the engine fuel supply given value wfDem=wf 慢车 .

[0059] In addition, it should be noted that when "the engine speed is close to the overspeed, the fuel quantity is directly set to the slow speed fuel quantity", the fuel quantity is no longer reduced by reducing the fuel quantity coefficient. For this purpose, the state value Flag can be set in the program to implement this function, that is, the initialization Flag is 0. When the engine speed is less than the speed setting value or the exhaust temperature is less than the temperature setting value, the Flag is modified to 1, and the original setting condition of the slow speed fuel quantity is modified to "when the speed n> speed setting value or the exhaust temperature T> temperature setting value or Flag=1, the engine fuel quantity given value wfDem=wf 慢车 . ” At this point, the engine fuel supply will continue to be set to the idle fuel quantity until the program exits.

[0060] In some optional embodiments, step S2 further includes:

[0061] Step S21: Determine the speed correction coefficient kdec_n according to the engine speed n:

[0062] kdec_n = a - (1 - a)(n - ndem - detn) / detn;

[0063] Where, a is the maximum acceleration fuel coefficient to ensure that the engine does not accelerate, 0 < a < 1, ndem is the planned value of speed control, detn is the overshoot limit value of speed, and the sum of ndem and detn is the set value of speed;

[0064] Step S22: Determine the temperature correction coefficient kdec_T according to the exhaust temperature T:

[0065] kdec_T = a - (1 - a)(T - Tdem - detT) / detT;

[0066] Where, Tdem is the planned value of temperature control, detT is the overshoot limit value of temperature, and the sum of Tdem and detT is the set value of temperature;

[0067] Step S23: Select the smaller value between the speed correction coefficient kdec_n and the temperature correction coefficient kdec_T as the correction coefficient k_wfmdec to correct the fuel supply amount given by the engine deceleration fuel supply law.

[0068] This embodiment gives the calculation process of the correction coefficient. Where, a is the maximum acceleration fuel coefficient to ensure that the engine does not accelerate, and its value range is 0 to 1), that is, when the fuel supply amount is a times the acceleration fuel, it can ensure that the engine is in a non-accelerating state.

[0069] In some optional implementation manners, after step S"3", it further includes:

[0070] Step S4: Determine the duration of abnormal fuel supply of the engine. When the duration of abnormal fuel supply of the engine exceeds the set value, switch the engine fuel supply to backup control or set a fixed fuel supply amount for fuel supply control.

[0071] This embodiment increases the duration, and the above logic is executed during the duration. On the contrary, if the engine has a backup control system, it will switch to the backup system control. If there is no backup, a fixed fuel supply amount can be set (not restricted by the acceleration and deceleration fuel supply laws) to ensure that the aircraft can safely return. In addition, it should be noted that the set value for monitoring the duration of abnormal fuel supply of the engine can be determined according to the inertia of the engine itself. Generally speaking, the set values for the abnormal fuel supply types of acceleration abnormality and deceleration abnormality of the engine are different.

[0072] In addition to jumping out of the control logic through time, the rising rate of speed can also be continuously monitored to control the program jump, that is, if the engine is in the acceleration fuel supply state, ndot ≥ 0; or if the engine is in the deceleration fuel supply state, ndot ≤ 0. At this time, it indicates that the engine is normal and the control logic of this application can be exited.

[0073] In the second aspect of the present application, a fuel supply control device for judging abnormal fuel supply based on the rotational speed increase rate corresponding to the above method is provided, mainly including:

[0074] An engine fuel supply abnormal type determination module, configured to determine the engine fuel supply abnormal type according to the engine fuel supply set value and the rotational speed increase rate;

[0075] An engine fuel supply given value calculation module, configured to select the maximum value between the fuel supply given by the engine acceleration fuel supply law and the fuel supply in the engine idle state as the engine fuel supply given value when the engine fuel supply abnormal type is acceleration abnormality, and when the engine fuel supply abnormal type is deceleration abnormality, the engine fuel supply given value is calculated by the following method:

[0076] When the engine speed is less than the speed set value or the exhaust gas temperature is less than the temperature set value, the fuel supply given by the engine deceleration fuel supply law is corrected based on the correction coefficient to obtain the engine fuel supply given value, otherwise, the fuel supply in the engine idle state is used as the engine fuel supply given value;

[0077] A fuel supply control module, configured to perform fuel supply control of the aeroengine based on the engine fuel supply given value.

[0078] In some optional embodiments, the engine fuel supply abnormal type determination module further includes:

[0079] A rotational speed increase rate acquisition unit, configured to acquire the engine fuel supply set value and the rotational speed increase rate, where the engine fuel supply set value includes acceleration fuel supply and deceleration fuel supply, and the rotational speed increase rate includes positive and negative values;

[0080] An abnormal type judgment unit, configured to determine that the engine fuel supply abnormal type is acceleration abnormality when the engine fuel supply set value is acceleration fuel supply and the rotational speed increase rate is negative; and determine that the engine fuel supply abnormal type is deceleration abnormality when the engine fuel supply set value is deceleration fuel supply and the rotational speed increase rate is positive.

[0081] In some optional embodiments, the engine fuel supply given value calculation module includes:

[0082] A rotational speed correction coefficient calculation unit, configured to determine the rotational speed correction coefficient kdec_n according to the engine speed n:

[0083] kdec_n = a - (1 - a)(n - ndem - detn) / detn;

[0084] Where, a is the maximum acceleration fuel coefficient to ensure that the engine does not accelerate, 0 < a < 1, ndem is the rotational speed control planned value, detn is the rotational speed overshoot limit value, and the sum of ndem and detn is the speed set value;

[0085] The temperature correction coefficient calculation unit is used to determine the temperature correction coefficient kdec_T according to the exhaust temperature T:

[0086] kdec_T=a-(1-a)(T-Tdem-detT) / detT;

[0087] Among them, Tdem is the temperature control plan value, detT is the temperature overshoot limit value, and the sum of Tdem and detT is the temperature set value;

[0088] The correction coefficient selection unit is used to select the smaller value of the speed correction coefficient kdec_n and the temperature correction coefficient kdec_T as the correction coefficient k_wfmdec to correct the fuel supply amount given by the engine deceleration fuel supply law.

[0089] In some optional embodiments, the oil supply control device further includes:

[0090] The time limit module is used to determine the duration of the engine fuel supply abnormality. When the duration of the engine fuel supply abnormality exceeds the set value, the engine fuel supply is switched to backup control or a fixed fuel supply amount is set for fuel supply control.

[0091] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A fuel supply control method for judging fuel supply abnormality based on the speed increase rate, characterized in that: Including: Step S1: Determine the abnormal type of engine fuel supply according to the engine fuel supply set value and the rotational speed rising rate. Step S2: When the abnormal type of engine fuel supply is abnormal acceleration, select the maximum value between the fuel supply amount given by the engine acceleration fuel supply law and the fuel supply amount in the engine idle state as the engine fuel supply set value. When the abnormal type of engine fuel supply is abnormal deceleration, the engine fuel supply set value is calculated by the following method: When the engine rotational speed is less than the rotational speed set value or the exhaust gas temperature is less than the temperature set value, correct the fuel supply amount given by the engine deceleration fuel supply law based on the correction coefficient to obtain the engine fuel supply set value. Otherwise, use the fuel supply amount in the engine idle state as the engine fuel supply set value. Step S3: Conduct fuel supply control for the aeroengine based on the engine fuel supply set value. Step S1 further includes: Step S11: Obtain the engine fuel supply set value and the rotational speed rising rate. The engine fuel supply set value includes acceleration fuel supply and deceleration fuel supply, and the rotational speed rising rate includes positive and negative values. Step S12: When the engine fuel supply set value is acceleration fuel supply and the rotational speed rising rate is negative, determine that the abnormal type of engine fuel supply is abnormal acceleration. When the engine fuel supply set value is deceleration fuel supply and the rotational speed rising rate is positive, determine that the abnormal type of engine fuel supply is abnormal deceleration. Step S2 further includes: Step S21: Determine the rotational speed correction coefficient kdec_n according to the engine rotational speed n: kdec_n = a - (1 - a)(n - ndem - detn) / detn; Where, a is the maximum acceleration fuel coefficient to ensure that the engine does not accelerate, 0 < a < 1, ndem is the rotational speed control planned value, detn is the rotational speed overshoot limit value, and the sum of ndem and detn is the rotational speed set value. Step S22: Determine the temperature correction coefficient kdec_T according to the exhaust gas temperature T: kdec_T = a - (1 - a)(T - Tdem - detT) / detT; Where, Tdem is the temperature control planned value, detT is the temperature overshoot limit value, and the sum of Tdem and detT is the temperature set value. Step S23: Select the smaller value between the rotational speed correction coefficient kdec_n and the temperature correction coefficient kdec_T as the correction coefficient k_wfmdec to correct the fuel supply amount given by the engine deceleration fuel supply law.

2. The fuel supply control method for determining fuel supply abnormality based on the speed increase rate according to claim 1, wherein: After Step S3, it further includes: Step S4: Determine the duration of engine fuel supply abnormality. When the duration of engine fuel supply abnormality exceeds the set value, switch the engine fuel supply to backup control or set a fixed fuel supply amount for fuel supply control.

3. A fuel supply control device for judging fuel supply abnormality based on the speed increase rate, characterized in that: A device for implementing the fuel supply control method for judging fuel supply abnormality based on the rotational speed rising rate as described in Claim 1, the device includes: An engine fuel supply abnormal type determination module, configured to determine the abnormal type of engine fuel supply according to the engine fuel supply set value and the rotational speed rising rate. An engine fuel supply set value calculation module, which is used to select the maximum value between the fuel supply given by the engine acceleration fuel supply law and the fuel supply in the engine idle state as the engine fuel supply set value when the engine fuel supply abnormal type is acceleration abnormality. When the engine fuel supply abnormal type is deceleration abnormality, the engine fuel supply set value is calculated by the following method: When the engine speed is less than the speed set value or the exhaust gas temperature is less than the temperature set value, the fuel supply given by the engine deceleration fuel supply law is corrected based on the correction coefficient to obtain the engine fuel supply set value. Otherwise, the fuel supply in the engine idle state is used as the engine fuel supply set value; A fuel supply control module, which is used to control the fuel supply of the aeroengine based on the engine fuel supply set value.

4. The fuel supply control device for determining fuel supply abnormality based on the rotational speed increase rate according to claim 3, wherein: The engine fuel supply abnormal type determination module further includes: A speed rise rate acquisition unit, which is used to acquire the engine fuel supply set value and the speed rise rate. The engine fuel supply set value includes acceleration fuel supply and deceleration fuel supply, and the speed rise rate includes positive value and negative value; An abnormal type judgment unit, which is used to determine that the engine fuel supply abnormal type is acceleration abnormality when the engine fuel supply set value is acceleration fuel supply and the speed rise rate is negative; and determine that the engine fuel supply abnormal type is deceleration abnormality when the engine fuel supply set value is deceleration fuel supply and the speed rise rate is positive.

5. The fuel supply control device for determining fuel supply abnormality based on the rotational speed increase rate according to claim 3, wherein: The engine fuel supply set value calculation module includes: A speed correction coefficient calculation unit, which is used to determine the speed correction coefficient kdec_n according to the engine speed n: kdec_n = a - (1 - a)(n - ndem - detn) / detn; Where, a is the maximum acceleration fuel coefficient to ensure that the engine does not accelerate, 0 < a < 1, ndem is the speed control planned value, detn is the speed overshoot limit value, and the sum of ndem and detn is the speed set value; A temperature correction coefficient calculation unit, which is used to determine the temperature correction coefficient kdec_T according to the exhaust gas temperature T: kdec_T = a - (1 - a)(T - Tdem - detT) / detT; Where, Tdem is the temperature control planned value, detT is the temperature overshoot limit value, and the sum of Tdem and detT is the temperature set value; A correction coefficient selection unit, which is used to select the smaller value between the speed correction coefficient kdec_n and the temperature correction coefficient kdec_T as the correction coefficient k_wfmdec to correct the fuel supply given by the engine deceleration fuel supply law.

6. The fuel supply control device for determining fuel supply abnormality based on the rotational speed increase rate according to claim 3, wherein: The fuel supply control device further includes: A time limit module, which is used to determine the duration of the engine fuel supply abnormality. When the duration of the engine fuel supply abnormality exceeds the set value, switch the engine fuel supply to backup control or set a fixed fuel supply for fuel supply control.

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