A solution to a mismatch fault of electric adjustment and backup a2 advance control function

Abstract

The application belongs to the field of electric control system, and particularly relates to a solution method for a mismatch fault between an electric control and backup a2 advance control function. The method comprises the following steps: step one, obtaining a first criterion for an electric control system entering an a2 advance control function and a second criterion for a backup system entering the a2 advance control function; step two, determining a third criterion for the backup system entering the a2 advance control function while the electric control system not entering the a2 advance control function according to the first criterion and the second criterion; and step three, determining a fault judgment logic according to the third criterion, and prolonging the adjustment time of the electric control system to avoid the occurrence of an a2 adjustment channel fault under the fault judgment logic. The solution method for the mismatch fault between the electric control and the backup a2 advance control function can avoid the fault reporting phenomenon caused by the backup system entering the a2 advance control function while the electric control system not entering the a2 advance control function, and can prevent both "false reporting" and "omission reporting".

Description

TECHNICAL FIELD

[0001] The application belongs to the field of electric control system, and particularly relates to a solution to a mismatch fault of electric control and backup a2 advance control function. BACKGROUND

[0002] The currently used aero-engine is an electric control system with mechanical hydraulic backup, wherein a2, the angle of adjustable blades at the inlet of the compressor, is a key part for adjusting the engine inlet flow rate. If a2 control fails, it may cause engine surge and other risks. Therefore, a2 control is completed by a digital electronic control system and a mechanical hydraulic backup system, which is a double guarantee for engine safety.

[0003] In the electric control state, the digital electronic controller outputs a duty ratio according to the deviation of the sensor acquisition value from the set target value, controls the position of the a2 valve sleeve, and then controls the a2 angle. The mechanical hydraulic system feeds back the a2 angle through a steel cable, compares it with the target value set in the main fuel pump regulator, and then controls the position of the a2 oil distribution valve, and then controls the a2 angle. In the electric control state, the digital electronic controller and the main fuel pump regulator jointly control the a2 angle, and after backup, only the main fuel pump regulator participates in the a2 angle control. When the engine decelerates, in order to make the a2 angle quickly follow the set target value, a2 advance control functions in the electric control state and the mechanical hydraulic backup state are respectively designed, which can achieve the purpose of quickly closing the a2 angle. Since the a2 advance control function in the electric control state is realized by the digital electronic controller, and the a2 advance control function in the backup state is realized by the main fuel pump regulator, it is two relatively independent systems. However, the main fuel pump regulator belongs to a mechanical structure, and there is a manufacturing tolerance, and there is also a decay problem in the use process, while the control accuracy of the digital electronic controller is unchanged, so there is a mismatch between the electric control and the backup a2 advance control function. The a2 regulation channel fault caused by the backup system entering the advance control while the electric control system does not enter the advance control may occur, and the control system may enter the a2 single channel backup control mode. The impact caused by such a fault is large, affecting the departure time of the aircraft. Although the mismatch between the electric control and the backup a2 advance control function does not affect the safety of the engine, the impact caused by the report is large, which belongs to the category of "false report". How to report the "a2 regulation channel fault" due to the mismatch between the electric control and the backup a2 advance control function without changing the hardware is a problem to be solved.

[0004] There are two solutions in the prior art to solve the mutual interference of a2 advance control. First, the a2 circuit of the electric governor control and the backup control is designed separately to achieve the purpose of not interfering with each other. The disadvantage is that hardware modification is required, and the production cycle and test verification cycle are longer. Second, the fault judgment time of the a2 regulation channel is extended as a whole, which can solve the problem of "false alarm", but the disadvantage is that if the a2 fault judgment time of all states is extended alone, it will affect the a2 fault judgment mode under other conditions, which may cause the risk of not being able to find out when the engine a2 control deviates, which belongs to the category of "missed alarm".

[0005] Therefore, it is desirable to have a technical solution to overcome or at least alleviate at least one of the aforementioned deficiencies of the prior art. SUMMARY

[0006] The purpose of the present application is to provide a solution to the mismatch fault of electric governor and backup a2 advance control function to solve at least one problem existing in the prior art.

[0007] The technical solution of the present application is:

[0008] A solution to the mismatch fault of electric governor and backup a2 advance control function, comprising:

[0009] Step one, obtaining a first criterion for the electric governor system to enter the a2 advance control function and a second criterion for the backup system to enter the a2 advance control function;

[0010] Step two, determining a third criterion for the backup system to enter the a2 advance control function and the electric governor system not to enter the a2 advance control function according to the first criterion and the second criterion;

[0011] Step three, determining a fault judgment logic according to the third criterion, giving the electric governor system an extended regulation time to avoid the occurrence of a2 regulation channel fault under the fault judgment logic.

[0012] In at least one embodiment of the present application, in step one,

[0013] The first criterion for the electric governor system to enter the a2 advance control function is that the difference between the actual engine speed and the speed target value under the electric governor state is greater than a first threshold value.

[0014] In at least one embodiment of the present application, in step one,

[0015] The second criterion for the backup system to enter the a2 advance control function is that the difference between the actual engine speed and the backup speed target value under the electric governor state is greater than a second threshold value.

[0016] In at least one embodiment of the present application, in step two, the third criterion that the backup system enters the a2 advance control function while the electric regulating system does not enter the a2 advance control function is:

[0017] A+B≤N2<C+D

[0018] Wherein, A represents the deviation required for the backup system to enter the a2 advance control function, B represents the backup speed target value in the electric regulating state, N2 represents the actual engine speed, C represents the speed target value in the electric regulating state, and D represents the deviation required for the electric regulating system to enter the a2 advance control function.

[0019] In at least one embodiment of the present application, in step three, the third criterion is used to give the electric regulating system an extended adjustment time to avoid the occurrence of a2 adjustment channel failure under the third criterion, and the method comprises:

[0020] According to the third criterion, a failure judgment logic is determined, and the failure judgment logic comprises an entry logic, an execution logic, and an exit logic;

[0021] The entry logic is:

[0022] A+B≤N2<C+D ①

[0023] F-E≥G and T 故障 ≥T+△T ②

[0024] F-E≥G and T 故障 ≥T ③

[0025] Wherein, N2 represents the actual engine speed, E represents the a2 actual angle, F represents the a2 control target value, G represents the failure judgment threshold value, T 故障 represents the failure duration, T represents the failure duration judgment threshold value, and △T represents the extended time in the mode in which the backup system enters the a2 advance control function while the electric regulating system does not enter the a2 advance control function;

[0026] The execution logic is:

[0027] If condition ① is met, an a2 adjustment channel failure is reported according to condition ②, and a2 single-channel backup control is performed;

[0028] Otherwise, an a2 adjustment channel failure is reported according to condition ③, and a2 single-channel backup control is performed;

[0029] The exit logic is:

[0030] N2-C≤P and T 退出 ≥T2;

[0031] Wherein, N2 represents the actual engine speed, C represents the speed target value in the electric governor state, P represents the speed difference value judgment threshold value of the exit logic, T 退出 represents the exit logic duration, and T2 represents the exit logic time threshold value.

[0032] The present application has at least the following beneficial technical effects:

[0033] The method for solving the mismatch fault between the electric governor and the backup a2 advance control function of the present application can avoid the fault phenomenon that the backup system enters the a2 advance control function while the electric governor system does not enter the a2 advance control function, and can prevent both "false reporting" and "omission reporting". BRIEF DESCRIPTION OF DRAWINGS

[0034] Fig. 1 is a fault condition diagram caused by the backup system entering the a2 advance control function while the electric governor system does not enter the a2 advance control function in an embodiment of the present application;

[0035] Fig. 2 is a schematic diagram of the relationship between the accelerator lever angle and the speed in an embodiment of the present application. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme of the embodiments of the present application will be described in more detail below in combination with the drawings of the embodiments of the present application. In the drawings, the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some of the embodiments of the present application, not all the embodiments. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation on the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. The embodiments of the present application will be described in detail below in combination with the drawings.

[0037] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "transverse", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the scope of protection of the present application.

[0038] The embodiments of the present application will be described in detail below in combination with the drawings. Figs. 1-2 The present application will be described in further detail.

[0039] The application provides a solution to the mismatch fault of electric adjustment and backup a2 advance control function, comprising the following steps:

[0040] Step one, obtaining a first criterion for the electric adjustment system to enter the a2 advance control function, and a second criterion for the backup system to enter the a2 advance control function;

[0041] Step two, determining a third criterion for the backup system to enter the a2 advance control function while the electric adjustment system does not enter the a2 advance control function according to the first criterion and the second criterion;

[0042] Step three, determining the fault judgment logic according to the third criterion, and giving the electric adjustment system a prolonged adjustment time to avoid the occurrence of a2 adjustment channel fault under the fault judgment logic.

[0043] The solution to the mismatch fault of electric adjustment and backup a2 advance control function provided by the application is a typical fault mode in which the backup system enters the a2 advance control function while the electric adjustment system does not enter the a2 advance control function, as shown in Fig. 1 Since the backup system enters the advance mode, the a2 actual value rapidly becomes large, forming a large deviation from the a2 target value, and the electric adjustment system will make corresponding adjustment to gradually make the a2 actual value consistent with the a2 target value. When the backup system exits the a2 advance control, the a2 actual value will suddenly become small, again generating a large deviation, and since the electric adjustment system does not enter the advance control and the actuator also has a certain response time, it cannot control the a2 to the target value in a very short time. When the deviation reaches a certain value and exceeds the fault judgment time, the control system will report an "a2 adjustment channel fault" and execute a2 single-channel backup control. Since the electric adjustment and backup control are two systems, the conditions for judging the engine deceleration do not match, which may cause the a2 controlled by the electric adjustment system to not satisfy the advance logic while the backup system satisfies the a2 advance logic, resulting in the mismatch of the electric adjustment and backup a2 advance control function.

[0044] To solve the above problems, the software algorithm is used to identify the mode in which the backup system enters the advance control while the electric adjustment system does not enter the advance control according to the principle of not changing or changing as little as possible the original hardware system, and then the corresponding adjustment time is given to the electric adjustment system to avoid the occurrence of a2 adjustment channel fault under this mode. Although the overall a2 fault judgment time can be prolonged to solve the "false alarm" problem, its disadvantage is that if the a2 fault judgment time of all states is simply prolonged, it will affect the a2 fault judgment mode under other conditions, which may cause the risk of not being able to timely find that the engine a2 control deviates, belonging to the "missed alarm" category. Therefore, it is of great significance to identify the mode in which the backup system enters the advance control while the electric adjustment system does not enter the advance control and only prolong the adjustment time for this mode.

[0045] In an embodiment of the present application, Fig. 2 The schematic diagram of the relationship between the angle and the speed of the electric throttle and the backup throttle is given, wherein the No. 1 curve represents the target speed in the backup state; the No. 2 curve represents the target speed in the electric throttle state; the No. 3 curve represents the backup target speed in the electric throttle state; and the No. 4 curve represents the actual engine speed.

[0046] Since the electric throttle control and the backup control are two systems, the conditions for determining that the engine enters the advance function are different. The electric throttle system determines that the a2 advance control function is entered when the difference between the No. 4 curve and the No. 2 curve is greater than a certain value, for example, 6%. The backup system determines that the a2 advance control function is entered when the difference between the No. 4 curve and the No. 3 curve is greater than a certain value, for example, 1%. In the electric throttle state, the No. 3 curve is higher than the No. 1 curve by a certain value, for example, 5%.

[0047] According to the above, in step one in the present application, the first criterion for the electric throttle system to enter the a2 advance control function is that the difference between the actual engine speed and the target speed in the electric throttle state is greater than a first threshold value. The second criterion for the backup system to enter the a2 advance control function is that the difference between the actual engine speed and the backup target speed in the electric throttle state is greater than a second threshold value.

[0048] According to the above criteria, the following condition classification is obtained:

[0049] 1) The difference between the No. 4 curve and the No. 2 curve is greater than 6% and the difference between the No. 4 curve and the No. 3 curve is greater than 1%. The electric throttle system and the backup system simultaneously enter the advance control function, and no fault is reported.

[0050] 2) The difference between the No. 4 curve and the No. 2 curve is less than 6% and the difference between the No. 4 curve and the No. 3 curve is less than 1%. The electric throttle system and the backup system do not enter the advance control function, and no fault is reported.

[0051] 3) The difference between the No. 4 curve and the No. 2 curve is greater than 6% and the difference between the No. 4 curve and the No. 3 curve is less than 1%. Due to mechanical structure limitation, this situation will not occur.

[0052] 4) The difference between the No. 4 curve and the No. 2 curve is less than 6% and the difference between the No. 4 curve and the No. 3 curve is greater than 1%. The backup system enters the advance control function while the electric throttle system does not enter the advance control function. In this condition, a fault is reported due to the mismatch of entering the advance control function.

[0053] Based on the above analysis, condition 4) is the cause of the fault, and therefore a third criterion for identifying that the backup system enters the a2 advance control function while the electric throttle system does not enter the a2 advance control function is proposed:

[0054] A + B ≤ N2 < C + D

[0055] Wherein, A represents the deviation required for the backup system to enter the a2 advance control function, B represents the backup speed target value in the electric governor state, N2 represents the actual engine speed, C represents the speed target value in the electric governor state, and D represents the deviation required for the electric governor system to enter the a2 advance control function.

[0056] The method for solving the mismatch fault of the electric governor and the backup a2 advance control function of the present application, in the mechanism analysis, when the speed is greater than the sum of the backup speed target value in the electric governor state and the deviation required for the backup system to enter the a2 advance function and is less than the sum of the speed target value in the electric governor state and the deviation required for the electric governor system to enter the a2 advance function, it indicates that the backup system enters the a2 advance control while the electric governor system does not enter the a2 advance control. After obtaining the third criterion that the backup system enters the a2 advance control function while the electric governor system does not enter the a2 advance control function, the fault judgment logic is determined according to the third criterion, the electric governor system is given an extended adjustment time, and the occurrence of the a2 adjustment channel fault under the third criterion is avoided, including:

[0057] The fault judgment logic determined according to the third criterion includes: entry logic, execution logic and exit logic;

[0058] The entry logic is:

[0059] A+B≤N2<C+D ①

[0060] F-E≥G and T 故障 ≥T+△T ②

[0061] F-E≥G and T 故障 ≥T ③

[0062] Wherein, N2 represents the actual engine speed, E represents the a2 actual angle, F represents the a2 control target value, G represents the fault judgment threshold, T 故障 represents the fault duration, T represents the fault duration judgment threshold, and △T represents the extended time in the mode that the backup system enters the a2 advance control function while the electric governor system does not enter the a2 advance control function;

[0063] The execution logic is:

[0064] If condition ① is met, the a2 adjustment channel fault is reported according to condition ②, and the a2 single-channel backup control is performed;

[0065] Otherwise, the a2 adjustment channel fault is reported according to condition ③, and the a2 single-channel backup control is performed;

[0066] The exit logic is:

[0067] N2-C≤P and T 退出 ≥T2;

[0068] Wherein, N2 represents the actual engine speed, C represents the speed target value in the electric control state, P represents the speed difference value judgment threshold value of the exit logic, T 退出 represents the exit logic duration, and T2 represents the exit logic time threshold value.

[0069] The solution method for the mismatch fault between the electric control and the backup a2 lead control function of the present application can effectively avoid the a2 regulation channel fault caused by the interference between the electric control and the backup on the premise of retaining the a2 lead control of the mechanical hydraulic backup based on the original hardware structure unchanged; the design of the software recognition algorithm and the execution logic can recognize the interference mode caused by the backup system entering the lead control function and the electric control system not entering the lead control function, and avoid the risk that the a2 control deviates and cannot be discovered in time due to the extension of all fault reporting time.

[0070] The solution method for the mismatch fault between the electric control and the backup a2 lead control function of the present application takes into account the functions of preventing "false reporting" and preventing "missing reporting", and can be directly applied in various aeroengines, and has good market application prospect.

[0071] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A solution to a fault caused by a mismatch between the electronic speed controller (ESC) and the backup A2 advance control function, characterized in that, include: Step 1: Obtain the first criterion for the ESC system to enter the A2 advance control function, and the second criterion for the backup system to enter the A2 advance control function; Step 2: Based on the first criterion and the second criterion, determine the third criterion that the backup system enters the a2 advance control function while the ESC system does not enter the a2 advance control function; Step 3: Determine the fault judgment logic based on the third criterion, extend the adjustment time of the ESC system, and avoid the occurrence of the A2 adjustment channel fault under the fault judgment logic.

2. The solution to the mismatch fault between the electronic speed controller and backup a2 advance control function as described in claim 1, characterized in that, In step one, The first criterion for the electronic speed control system to enter the a2 advanced control function is: the difference between the actual engine speed and the target speed value under electronic speed control is greater than a first threshold.

3. The solution to the mismatch fault between the electronic speed controller and backup a2 advance control function as described in claim 2, characterized in that, In step one, The second criterion for the backup system to enter the a2 advanced control function is: the difference between the actual engine speed and the backup speed target value under electronic control is greater than the second threshold.

4. The solution to the mismatch fault between the electronic speed controller and backup a2 advance control function as described in claim 3, characterized in that, In step two, the third criterion for the backup system entering the a2 advance control function while the ESC system does not is: A+B≤N2<C+D Where A represents the deviation required for the backup system to enter the a2 advanced control function, B represents the target speed value of the backup in the electronic speed control state, N2 represents the actual engine speed, C represents the target speed value in the electronic speed control state, and D represents the deviation required for the electronic speed control system to enter the a2 advanced control function.

5. The solution to the mismatch fault between the electronic speed controller and backup a2 advance control function as described in claim 4, characterized in that, In step three, extending the adjustment time of the electronic control system according to the third criterion to avoid the occurrence of a2 adjustment channel failure under the third criterion includes: The fault judgment logic is determined according to the third criterion, and the fault judgment logic includes: entry logic, execution logic, and exit logic; The entry logic is as follows: A+B≤N²<C+D ① FE≥G and T 故障 ≥T+△T ② FE≥G and T 故障 ≥T③ Where N2 represents the actual engine speed, E represents the actual angle a2, F represents the target control value of a2, G represents the fault judgment threshold, and T... 故障 The fault duration is represented by T, which represents the fault duration judgment threshold. △T represents the extended time when the backup system enters the a2 advanced control function mode while the ESC system does not enter the a2 advanced control function mode. The execution logic is as follows: If condition ① is met, then report the a2 adjustment channel fault according to condition ②, and perform a2 single channel to backup control; Otherwise, report a2 adjustment channel failure according to condition ③, and switch a2 single channel to backup control; The exit logic is as follows: N²-C≤P and T 退出 ≥T2; Where N2 represents the actual engine speed, C represents the target speed value under electronic speed control, P represents the speed difference judgment threshold for exiting the logic, and T 退出 T1 represents the duration of the exit logic, and T2 represents the time threshold for the exit logic.

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