Method and system for accelerating control of turbofan engine

Abstract

The present invention provides a method for accelerating control of a turbofan engine, comprising: using on-board sensors to measure one or more operating parameters of the turbofan engine; determining that the operating state of the turbofan engine enters an acceleration process; calculating the corrected fuel flow rate and the acceleration rate of the turbofan engine and selecting the smaller value of both the corrected fuel flow rate and the fuel flow rate corresponding to the acceleration rate as the physical fuel flow rate of the turbofan engine; determining one or more acceleration characteristics of the turbofan engine based on the one or more operating parameters; and controlling the acceleration process of the turbofan engine according to the one or more acceleration characteristics and the physical fuel flow rate. In addition, the present invention also provides a system for accelerating control of a turbofan engine. The present invention uses existing on-board sensors to identify the engine acceleration characteristics, formulate adjustment rules under constraints, achieve acceleration, and improve the working safety of the engine and the flight safety.

Description

Technical Field

[0001] The present invention relates to a turbofan engine, and more particularly, to a method and system for accelerating control of a turbofan engine. Background Art

[0002] A turbofan engine includes a core engine and a low-pressure component. The core engine includes a high-pressure compressor and a high-pressure turbine, and the low-pressure component includes a low-pressure turbine, a booster stage, and a fan. Acceleration refers to the process in which the engine transitions from a low-speed stable operating state to another high-speed stable operating state within a certain period of time.

[0003] When the engine operates stably in the idle state or at a relatively small thrust state, the fuel supply amount is the steady-state fuel supply amount, the power of the compressor and the turbine is equal, and the engine speed is the steady-state speed. If the throttle lever is then quickly increased from a relatively small angle to another angle at this time, the fuel supply amount must increase rapidly and be greater than the steady-state fuel supply amount, the total temperature in front of the turbine increases rapidly, the turbine power is greater than the compressor power, the engine speed and some other parameters all increase rapidly, and finally it stabilizes at another operating point. During this process, the engine is mainly restricted in the following aspects: requirements of airworthiness-related terms, restrictions on compressor stability requirements, restrictions on turbine blade strength conditions, and restrictions on rotor acceleration. If the fuel supply amount is maintained at the maximum value allowed by the above various restrictions at each engine speed, the shortest acceleration time can be obtained.

[0004] Current engine acceleration control laws generally utilize fuel flow rate, and there are problems such as fault handling. Estimating the engine health degradation situation in real time based on a performance model and feeding it back to life extension control has problems such as insufficient model accuracy or the need for a large amount of data to correct the model.

[0005] During the acceleration process of the engine throughout its life cycle, faults may occur or the engine limit conditions may be exceeded. It is particularly important to be able to identify the fault risks and omens in real time during the engine acceleration process, predict according to specific criteria, optimize and adjust the control law online, and meet the safety acceleration control method under design limitations. On an engine test bench, a variety of sensors or monitoring devices can be used to judge faults, and safety measures can be taken to exit the fault, and the law can be optimized again after stopping the engine to conduct tests. However, during flight in an airline, only engine-mounted speed, temperature, or pressure signals can be used to optimize the control law. Within the restricted range, the acceleration control law is optimized in real time, not only by adjusting the fuel supply method, but also by controlling the variable geometric area. Summary of the Invention

[0006] The present invention content is provided to introduce some concepts in a simplified form that will be further described in the following detailed description. The present invention content is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to be used to assist in determining the scope of the claimed subject matter.

[0007] Due to the requirements of airworthiness-related terms, the limitations of compressor stability requirements, the limitations of turbine blade strength conditions, and the limitations of rotor acceleration, if the engine fuel supply law and the variable geometry area control law cannot be adjusted according to the current state of the engine, after the first acceleration fails, the next acceleration may still not be successful, and it is impossible to achieve the speed corresponding to the rated thrust. Accordingly, the object of the present invention is to improve the method and system for accelerating control of a turbofan engine to improve the working safety of the engine and the flight safety.

[0008] According to a first aspect of the present invention, there is provided a method for accelerating control of a turbofan engine, the method may include: using on-board sensors to measure one or more operating parameters of the turbofan engine; determining that the operating state of the turbofan engine enters an acceleration process; calculating the corrected fuel flow rate and the acceleration rate of the turbofan engine and selecting the smaller value of the corrected fuel flow rate and the fuel flow rate corresponding to the acceleration rate as the physical fuel flow rate of the turbofan engine; determining one or more acceleration characteristics of the turbofan engine at least partially based on the one or more operating parameters; and controlling the acceleration process of the turbofan engine according to the one or more acceleration characteristics and the physical fuel flow rate.

[0009] According to a second aspect of the present invention, there is provided a system for accelerating control of a turbofan engine, the system may include: a parameter measurement module configured to measure one or more operating parameters of the turbofan engine; a characteristic determination module configured to determine that the operating state of the turbofan engine enters an acceleration process, calculate the corrected fuel flow rate and the acceleration rate of the turbofan engine and select the smaller value of the corrected fuel flow rate and the fuel flow rate corresponding to the acceleration rate as the physical fuel flow rate of the turbofan engine, and determine one or more acceleration characteristics of the turbofan engine at least partially based on the one or more operating parameters; and an acceleration control module configured to control the acceleration process of the turbofan engine according to the one or more acceleration characteristics and the physical fuel flow rate.

[0010] The present invention uses existing on-board sensors to identify the engine acceleration characteristics, formulates adjustment laws under constraints, realizes acceleration, and improves the working safety of the engine and the flight safety.

[0011] These and other aspects of the present invention will be more fully understood after reading the following detailed description. After reading the following description of specific implementations of the present invention in conjunction with the accompanying drawings, other aspects, features, and implementations of the present invention will be apparent to those of ordinary skill in the art. Although the features of the present invention may be discussed below with respect to certain implementations and drawings, all implementations of the present invention may include one or more of the advantageous features discussed herein. In other words, although one or more implementations may be discussed as having certain advantageous features, one or more of such features may also be used in accordance with the various implementations of the present invention discussed herein. In a similar manner, although some implementations may be discussed below as device, system, or method implementations, it should be understood that such implementations may be implemented in a variety of devices, systems, and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] To understand in detail the manner in which the above-described features of the present invention are utilized, a more specific description of the above briefly summarized content may be made with reference to the embodiments, some aspects of which are shown in the accompanying drawings. It should be noted, however, that the drawings only show certain typical aspects of the present invention and should not be considered as limiting its scope, as the description may allow for other equally effective aspects.

[0013] Figure 1 A flowchart of a method for accelerating control of a turbofan engine according to an embodiment of the present invention is illustrated.

[0014] Figure 2 A process for determining whether surge stall has occurred according to an embodiment of the present invention is illustrated.

[0015] Figure 3 A schematic diagram for determining whether surge stall has occurred according to an embodiment of the present invention is illustrated.

[0016] Figure 4 A process for determining whether overtemperature has occurred according to an embodiment of the present invention is illustrated.

[0017] Figure 5 A schematic diagram for determining whether overtemperature has occurred according to an embodiment of the present invention is illustrated.

[0018] Figure 6 A schematic diagram for controlling the acceleration process in the case of surge stall and overtemperature according to an embodiment of the present invention is illustrated.

[0019] Figure 7 A process for determining whether engine bleed air is required according to an embodiment of the present invention is illustrated.

[0020] Figure 8Explains a process for determining whether the acceleration time is insufficient according to an embodiment of the present invention.

[0021] Figure 9 Explains a flowchart of another more detailed method for accelerating control of a turbofan engine according to an embodiment of the present invention.

[0022] Figure 10 Explains a block diagram of a system for accelerating control of a turbofan engine according to an embodiment of the present invention.

[0023] Figure 11 Explains a specific fuel design loop using a proportional-integral-derivative (PID) controller. Detailed implementation

[0024] The following detailed description, presented in conjunction with the accompanying drawings, is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein can be practiced. The detailed description includes specific details to provide a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts can be practiced without these specific details. In addition, alternative configurations can be designed without departing from the scope of the present invention. Additionally, well-known elements will not be described in detail or will be omitted so as not to obscure the relevant details of the present invention.

[0025] Figure 1 Explains a flowchart of method 100 for accelerating control of a turbofan engine according to an embodiment of the present invention. Method 100 can start at block 110, where one or more operating parameters of the turbofan engine are measured using on-board sensors, and this measurement can be performed online. In one example, the on-board sensors can include various speed, temperature, or pressure sensors. The one or more operating parameters can include one or more of the following: the low-pressure shaft speed N1 of the turbofan engine, the total temperature T2 at the inlet of the low-pressure compressor, the high-pressure shaft speed N2, the total temperature T25 at the inlet of the high-pressure compressor, the total pressure P25 at the inlet of the high-pressure compressor, the engine operating ambient pressure P0, the static pressure PS3 at the outlet of the high-pressure compressor, the engine exhaust gas temperature EGT, the static pressure P3b in the aircraft bleed air duct, the acceleration time, etc.

[0026] At block 120, method 100 can include determining that the operating state of the turbofan engine has entered an acceleration process. In one example, this determination can be at least partially based on a comparison of the low-pressure shaft speed with the target speed corresponding to the throttle lever. For example:

[0027] The criterion (adjustable parameter) for determining entry into the acceleration process is:

[0028] N 1R,PLA - N1 ≥ a × N 1R,100％ …………………………(1)

[0029] The criterion (adjustable parameter) for determining the end of the acceleration process is as follows:

[0030] N 1R,PLA -N1 ≤ b × N 1R,100％ …………………………(2)

[0031] where N1 is the current low-pressure shaft speed, N 1R,PLA is the target speed corresponding to the throttle lever, N 1R,100％ is the design point speed (a constant measure under the operating condition with lower energy consumption), and a and b are adjustable coefficients (percentages).

[0032] In block 130, method 100 may include calculating the corrected fuel flow rate and the acceleration rate of a turbofan engine and selecting the smaller value of both the corrected fuel flow rate and the fuel flow rate corresponding to the acceleration rate as the physical fuel flow rate of the turbofan engine.

[0033] In one example, the corrected fuel flow rate WFR may be determined based on the initially designed corrected fuel flow rate WF, the static pressure PS3 at the outlet of the high-pressure compressor, and the total temperature T25 at the inlet of the high-pressure compressor, and may be calculated, for example, by Equation (3):

[0034]

[0035] where γ ac and σ ac are both adjustable parameters with a range of 0 to 1.

[0036] In another example, the corrected fuel flow rate WFR may be determined by Equation (4):

[0037]

[0038] where f ac1 is the initial fuel supply law limit corresponding to the surge margin, and f ac2 is the fuel supply law limit corresponding to the temperature limit.

[0039] The acceleration rate N2dot can be obtained by extracting the first derivative of the high-pressure shaft speed N2 from the speed signal, where N2dot = dN2 / dt. For ease of calculation, the present invention uses the high-pressure corrected speed N2R, where N2R = N2 / (T25 / 288.15)^0.5, and the acceleration rate can be expressed by That is, N2dot is related to N2R and P0. In order to quickly determine the desired acceleration rate during actual operation, the values of N2R and P0 can be refined and equally divided into m parts to obtain the look-up table shown in Table 1 below, so that after obtaining the values of N2R and P0, the expected value of N2dot can be conveniently determined by looking up the table.

[0040] N2R <![CDATA[N2R1]]> <![CDATA[N2R2]]> … <![CDATA[N2R m-1 > <![CDATA[N2R m > <![CDATA[P01]]> N2dot <![CDATA[N2dot 1,1 > <![CDATA[N2dot 1,2 > … <![CDATA[N2dot 1,m-1 > <![CDATA[N2dot 1,m > <![CDATA[P02]]> N2dot <![CDATA[N2dot 2,1 > <![CDATA[N2dot 2,2 > … <![CDATA[N2dot 2,m-1 > <![CDATA[N2dot 2,m > … N2dot … … … … … <![CDATA[P0 m > N2dot <![CDATA[N2dot n,1 > <![CDATA[N2dot n,2 > … <![CDATA[N2dot n,m-1 > <![CDATA[N2dot n,m >

[0041] Table 1 N2dot expected value

[0042] It is known to those of ordinary skill in the art that according to classical control theory, a specific acceleration rate is associated with and / or corresponds to a specific fuel flow rate. For example, a proportional-integral-derivative (PID) controller can be employed to regulate / control the fuel flow rate W using the acceleration rate N2dot. Figure 11 Illustrates a specific fuel design loop employing a PID controller.

[0043] Generally speaking, the converted fuel flow rate mainly considers boundary limitations, and the acceleration rate mainly considers acceleration smoothness. In the present invention, a low-selection control can be performed on the converted fuel flow rate and the fuel flow rate corresponding to the acceleration rate as the basis for accelerating fuel supply, that is, the smaller value of the converted fuel flow rate and the fuel flow rate corresponding to the acceleration rate is selected as the physical fuel flow rate of the turbofan engine, thereby comprehensively considering boundary limitations and acceleration smoothness and making the acceleration control more reliable and efficient.

[0044] In block 140, method 100 may include determining one or more acceleration characteristics of the turbofan engine at least in part based on the one or more operating parameters. The one or more acceleration characteristics may include surge or surge precursors, over-temperature or over-temperature precursors, adjusting the fuel supply amount, bleed air correction, bleed and bleed correction, and so on. The following refers to Figures 2 - 8 to further describe the operation of block 140 in detail.

[0045] In block 150, method 100 may include controlling the acceleration process of the turbofan engine based on the one or more acceleration characteristics and the physical fuel flow rate. In one example, controlling the acceleration process of the turbofan engine may include adjusting the actual physical fuel flow rate, performing bleed air correction, performing bleed correction, etc. in the event of one or more acceleration characteristics. The following refers to Figures 2 - 8 to further describe the operation of block 150.

[0046] Figure 2The process 200 for determining whether surge stall occurs according to an embodiment of the present invention is explained. In one example, surge or surge precursor can be determined at least in part based on the comparison of the first-order time derivative PS3dot of the static pressure PS3 at the outlet of the high-pressure compressor (where PS3dot = dPS3 / dt) with a threshold. For the convenience of calculation, in the present invention, whether surge or surge precursor occurs in a turbofan engine is determined by comparing the B value (where B = PS3dot / PS3) with the threshold Bthd. For example, at block 210, the process 200 may include determining whether the B value is less than the threshold Bthd. If it is determined at block 210 that the B value is less than the threshold Bthd, then it is determined at block 220 that surge or surge precursor exists. Otherwise, if it is determined at block 210 that the B value is not less than the threshold Bthd, then it is determined at block 230 that no surge or surge precursor exists.

[0047] Figure 3 The schematic diagram 300 for determining whether surge stall occurs according to an embodiment of the present invention is explained. In Figure 3 it, the horizontal axis represents the N2R value and the vertical axis represents the B value. In one example, the threshold Bthd can be set according to experience, according to tests, or as needed. In another example, the threshold Bthd can be determined by looking up values in a lookup table of the high-pressure corrected speed N2R relationship. As Figure 3 shown, if the B value is not less than the threshold Bthd, then no surge or surge precursor occurs; otherwise, surge or surge precursor occurs.

[0048] Figure 4 The process 400 for determining whether overtemperature occurs according to an embodiment of the present invention is explained. In one example, overtemperature or overtemperature precursor can be determined at least in part based on the comparison of the engine exhaust gas temperature EGT with the threshold EGTthd. For example, at block 410, the process 400 may include determining whether the engine exhaust gas temperature EGT is greater than the threshold EGTthd. If it is determined at block 410 that the engine exhaust gas temperature EGT is greater than the threshold EGTthd, then it is determined at block 420 that overtemperature or overtemperature precursor exists. Otherwise, if it is determined at block 410 that the engine exhaust gas temperature EGT is not greater than the threshold EGTthd, then it is determined at block 430 that no overtemperature or overtemperature precursor exists.

[0049] Figure 5 The schematic diagram 500 for determining whether overtemperature occurs according to an embodiment of the present invention is explained. In Figure 5 it, the horizontal axis represents the N2R value and the vertical axis represents the EGT value. In one example, the threshold EGTthd can be set according to experience, according to tests, or as needed. In another example, the threshold EGTthd can be determined by looking up values in a lookup table of the high-pressure corrected speed N2R relationship. As Figure 5As shown, if the EGT value is less than the threshold EGTthd, then no over-temperature or over-temperature precursor occurs; otherwise, over-temperature or over-temperature precursor occurs.

[0050] Figure 6 FIG. 600, which illustrates a schematic diagram for controlling an acceleration process in the case of surge stall and over-temperature according to an embodiment of the present invention, is described. In one example, if it is determined that there is surge or a surge precursor (block 610), then the operation of controlling the acceleration process of the turbofan engine may include: reducing the physical fuel flow rate of the turbofan engine (block 620). The actual fuel reduction amount can be expressed as ΔWFR = ΔWFR(N2R, ΔB), that is, ΔWFR is related to the values of N2R and ΔB, where ΔB is the difference between the actually measured B value and the threshold Bthd. Similar to the acceleration rate, ΔWFR can also be obtained through a look-up table (e.g., Table 2).

[0051] N2R 0 <![CDATA[N2R1]]> <![CDATA[N2R2]]> … <![CDATA[N2R m-1 > <![CDATA[N2R m > <![CDATA[ΔB1]]> ΔWFR 0 <![CDATA[ΔWFR 1,1 > <![CDATA[ΔWFR 1,2 > … <![CDATA[ΔWFR 1,m-1 > <![CDATA[ΔWFR 1,m > <![CDATA[ΔB2]]> ΔWFR 0 <![CDATA[ΔWFR 2,1 > <![CDATA[ΔWFR 2,2 > … <![CDATA[ΔWFR 2,m-1 > <![CDATA[ΔWFR 2,m > … ΔWFR … … … … … … <![CDATA[ΔB n > ΔWFR 0 <![CDATA[ΔWFR n.1 > <![CDATA[ΔWFR n.2 > … <![CDATA[ΔWFR n,m-1 > <![CDATA[ΔWFR n,m >

[0052] Table 2 Relationship between ΔB and fuel reduction amount ΔWFR

[0053] In another example, if it is determined that there is over-temperature or an over-temperature precursor (block 630), then the operation of controlling the acceleration process of the turbofan engine may include: reducing the physical fuel flow rate of the turbofan engine (block 640). The actual fuel reduction amount can be expressed as ΔWFR = ΔWFR(N2R, ΔEGT / T2), that is, ΔWFR is related to the values of N2R and ΔEGT / T2, where ΔEGT is the difference between the actually measured EGT value and the threshold EGTthd.

[0054] Similar to the acceleration rate, this ΔWFR can also be obtained through a look-up table (e.g., Table 3).

[0055] N2R 0 <![CDATA[N2R1]]> <![CDATA[N2R2]]> … <![CDATA[N2R m-1 > <![CDATA[N2R m > <![CDATA[ΔEGT1 / T2]]> ΔWFR 0 <![CDATA[ΔWFR 1,1 > <![CDATA[ΔWFR 1,2 > … <![CDATA[ΔWFR 1,m-1 > <![CDATA[ΔWFR 1,m > <![CDATA[ΔEGT2 / T2]]> ΔWFR 0 <![CDATA[ΔWFR 2,1 > <![CDATA[ΔWFR 2,2 > … <![CDATA[ΔWFR 2,m-1 > <![CDATA[ΔWFR 2,m > … ΔWFR 0 … … … … … <![CDATA[ΔEGT n / T2]]> ΔWFR 0 <![CDATA[ΔWFR n.1 > <![CDATA[ΔWFR n.2 > … <![CDATA[ΔWFR n,m-1 > <![CDATA[ΔWFR n,m >

[0056] Table 3 Relationship between ΔEGT / T2 and fuel reduction amount ΔWFR

[0057] During flight, it is usually necessary to pressurize the cabin so that the air pressure inside the cabin remains at a certain level. To achieve the pressurization effect, a series of pressurization devices are required. A typical modern aircraft is achieved by the coordinated operation of an air source system, a temperature control system, a cabin air distribution system, and a pressure control system. The air source system is responsible for bleeding air into the cabin, and the bleeding air can be achieved in three ways (i.e., engine bleeding, auxiliary power unit (APU) bleeding, and ground air source vehicle bleeding). The air source for engine bleeding is taken from the compressor of the turbofan engine. The bleeding process will increase the fuel consumption of the engine, so it may be necessary to increase the fuel flow rate during engine acceleration to achieve the expected acceleration time.

[0058] Figure 7The process 700 for determining whether engine bleed air is required according to an embodiment of the present invention is described. The process 700 may include determining whether bleed air is required at block 710. If bleed air is required, then increasing the fuel flow rate is determined at block 720, otherwise not increasing the fuel flow rate is determined at block 730. The actual fuel addition amount can be expressed as ΔWFR = ΔWFR(N2R, P3b, PS3), that is, ΔWFR is related to the values of N2R, P3b, and PS3. The ratio of P3b to PS3 can be referred to as the bleed air coefficient, which can be obtained through calculation or testing. Similar to the acceleration rate, this ΔWFR can also be obtained through a look-up table (e.g., Table 4).

[0059] N2R 0 <![CDATA[N2R1]]> <![CDATA[N2R2]]> … <![CDATA[N2R m-1 > <![CDATA[N2R m > P3b / PS3 = 0 ΔWFR 0 <![CDATA[ΔWFR 1,1 > <![CDATA[ΔWFR 1,2 > … <![CDATA[ΔWFR 1,m-1 > <![CDATA[ΔWFR 1,m > <![CDATA[P3b / PS3 = c1]]> ΔWFR 0 <![CDATA[ΔWFR 2,1 > <![CDATA[ΔWFR 2,2 > … <![CDATA[ΔWFR 2,m-1 > <![CDATA[ΔWFR 2,m > … ΔWFR … … … … … … <![CDATA[P3b / PS3 = c n-1 > ΔWFR 0 <![CDATA[ΔWFR n.1 > <![CDATA[ΔWFR n.2 > … <![CDATA[ΔWFR n,m-1 > <![CDATA[ΔWFR n,m >

[0060] Table 4 Relationship between Bleed Air Coefficient and Fuel Addition Amount ΔWFR

[0061] The acceleration time is also an important indicator for measuring the performance of the acceleration process. Generally, it is required that the difference between the required acceleration time Time_D and the actual acceleration time Time_K should be greater than a threshold DT (i.e., the required time difference). Usually, the smaller the actual acceleration time Time_K, the better. If the difference exceeds the threshold DT, then no air bleeding is required. If Time_D - Time_K < DT occurs, it indicates that the engine may be deteriorating and reducing the fuel supply alone cannot complete the acceleration within the specified time. At this time, if the engine transient bleed air valve α TBV_K is less than the threshold α TBV MAX , that is, α TBV_K < α TBV MAX , then consider the combined control of air bleeding and fuel addition in the low rotational speed range. The air bleeding rule is shown in Table 5 below. At this time, if the engine transient bleed air valve α TBV_K is greater than the threshold α TBV MAX , prompt engine maintenance after the engine stops.

[0062] N2R 0 <![CDATA[N2R1]]> <![CDATA[N2R2]]> … <![CDATA[N2R m-1 > <![CDATA[N2R m > <![CDATA[DT=T1]]> <![CDATA[α TBV_K > 0 <![CDATA[α TBV_K 1,1 > <![CDATA[α TBV_K 1,2 > … 0 0 <![CDATA[DT=T2]]> <![CDATA[α TBV_K > 0 <![CDATA[α TBV_K 2,1 > <![CDATA[α TBV_K 2,2 > … 0 0 … <![CDATA[α TBV_ K]]> … … … … … … <![CDATA[DT=T n > <![CDATA[α TBV_K > 0 <![CDATA[α TBV_K n.1 > <![CDATA[α TBV_K n.2 > … 0 0

[0063] Table 5 Air Bleeding Rule

[0064] Figure 8 The process 800 for determining whether the acceleration time is insufficient according to an embodiment of the present invention is described. The process 800 may include determining whether the acceleration time is insufficient at block 810, that is, whether the difference between the required acceleration time Time_D and the actual acceleration time Time_K is less than the threshold DT. If so, then determining to bleed air and add fuel at block 820. Otherwise, determining that no air bleeding and fuel addition are required at block 830.

[0065] Figure 9 The flowchart of another more detailed method 900 for the acceleration control of a turbofan engine according to an embodiment of the present invention is described.

[0066] Method 900 may start at block 905, where the engine is in a steady state at a constant speed.

[0067] At block 910, method 900 may include determining whether the engine has entered an acceleration process. The operation of block 910 may be similar to the operation of block 120 described above. If it is determined at block 910 that the engine has entered an acceleration process, then method 900 proceeds to block 920. Otherwise, if it is determined at block 910 that the engine has not entered an acceleration process (e.g., the acceleration process has ended), then method 900 proceeds to block 915.

[0068] At block 915, method 900 may include recording the acceleration time.

[0069] At block 920, method 900 may include determining whether bleed air is required. The operation of block 920 may be similar to the operation of block 710 described above. If it is determined at block 920 that bleed air is required, then method 900 may proceed to block 925, otherwise method 900 may proceed to block 930.

[0070] At block 925, method 900 may include performing bleed air correction, such as increasing the fuel flow of the turbofan engine. The operation of block 925 may be similar to the operation of block 720.

[0071] At block 930, method 900 may include performing a minimum selection control on the corrected fuel flow and the fuel flow corresponding to the acceleration rate as the basis for accelerating fuel supply, that is, selecting the smaller value of the corrected fuel flow and the fuel flow corresponding to the acceleration rate as the physical fuel flow of the turbofan engine. The operation of block 930 may be similar to the operation of block 130 described above.

[0072] At block 940, method 900 may include determining whether surge or surge precursors occur. The operation of block 940 may be similar to the operation of block 210 described above. If it is determined at block 940 that surge has occurred, then method 900 may proceed to block 945, otherwise method 900 may return to block 910.

[0073] At block 945, method 900 may include performing surge fuel cut. The operation of block 945 may be similar to the operation of block 620 described above.

[0074] At block 950, method 900 may include determining whether overtemperature or overtemperature precursors occur. The operation of block 950 may be similar to the operation of block 410 described above. If it is determined at block 950 that overtemperature has occurred, then method 900 may proceed to block 955, otherwise method 900 may return to block 910.

[0075] At block 955, method 900 may include performing over-temperature fuel reduction. The operation of block 955 may be similar to the operation of block 640 described above.

[0076] At block 960, method 900 may include determining whether the acceleration time is insufficient. The operation of block 960 may be similar to the operation of block 810 described above. If it is determined at block 960 that the acceleration time is insufficient, then method 900 may proceed to block 965; otherwise, method 900 may return to block 910.

[0077] At block 965, method 900 may include performing deflation fueling. The operation of block 965 may be similar to the operation of block 820 described above.

[0078] As described above, the present invention uses existing on-board sensors to identify the engine acceleration characteristics, formulate adjustment rules under constraints, achieve acceleration, and improve the engine operating safety and flight safety. Since the present invention sets multiple segmented quantization parameters for acceleration, they can be stored during flight and evaluated in real time with the segmented target values, adjust the control rules, and conduct acceleration research based on the quantization parameters after the flight ends. The adjustment means of the present invention can also be applied to the overall engine bench test of aeroengines to achieve acceleration, which is beneficial to improving test safety and efficiency and reducing the difficulty of test data mining. The adjustment means of the present invention can detect potential surge, over-temperature, and acceleration timeout fault precursors of the engine during the entire life cycle, handle them during the acceleration process, and provide guidance for engine maintenance. The present invention can also be used for the acceleration of ground gas turbines and marine gas turbines, which is beneficial to improving the operation safety and efficiency of gas turbines and reducing the difficulty of test data mining.

[0079] Figure 10 A block diagram of a system 1000 for turbofan engine acceleration control according to an embodiment of the present invention is illustrated. System 1000 may include a parameter measurement module 1010. The parameter measurement module 1010 may include various rotational speed, temperature, or pressure sensors. The parameter measurement module 1010 may be configured to implement the operation of block 110, that is, measure one or more operating parameters of the turbofan engine.

[0080] System 1000 may further include a feature determination module 1020. The feature determination module 1020 may be implemented using software, hardware, or a combination of both. The feature determination module 1020 may be configured to implement the operations of block 120, block 130, and block 140, that is, to determine that the operating state of the turbofan engine enters an acceleration process, calculate the corrected fuel flow rate and the acceleration rate of the turbofan engine, and select the smaller value of both the corrected fuel flow rate and the fuel flow rate corresponding to the acceleration rate as the physical fuel flow rate of the turbofan engine, and to determine one or more acceleration characteristics of the turbofan engine based at least in part on one or more operating parameters. In addition, the feature determination module 1020 may also be configured to implement the operation of one or more of block 920, block 940, block 950, and block 960.

[0081] System 1000 may also include an acceleration control module 1030. The acceleration control module 1030 may be implemented using software, hardware, or a combination of both. The acceleration control module 1030 may be configured to implement the operation of block 150, that is, to control the acceleration process of the turbofan engine according to one or more acceleration characteristics and the physical fuel flow rate. In addition, the acceleration control module 1030 may also be configured to implement the operation of one or more of block 925, block 945, block 955, and block 965.

[0082] Other aspects

[0083] The examples set forth herein are for illustrative purposes to explain certain concepts of the present invention. Those of ordinary skill in the art will understand that these examples are merely illustrative in nature, and other examples may fall within the scope of the present invention and the appended claims. Based on the teachings herein, those skilled in the art should appreciate that the aspects disclosed herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of the aspects set forth herein can be used to implement a device or practice a method. Additionally, other structures, functions, or a combination of structures and functions that are complementary to or different from one or more of the aspects set forth herein can be used to implement such a device or practice such a method.

[0084] In the description herein, it should be understood that the terms "first", "second", "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0085] Those skilled in the art will appreciate that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0086] In addition, those skilled in the art will appreciate that the various illustrative logical blocks, modules, circuits, and algorithmic steps described in connection with the aspects disclosed herein can be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

[0087] One or more of the components, steps, features, and / or functions described above can be rearranged and / or combined into a single component, step, feature, or function, or can be implemented in several components, steps, or functions. Additional elements, components, steps, and / or functions can also be added without departing from the novel features disclosed herein. The apparatus, devices, and / or components described above can be configured to perform one or more of the methods, features, or steps described herein. The novel algorithms described herein can also be efficiently implemented in software and / or embedded in hardware.

[0088] It should be understood that the specific order or hierarchy of the steps in the disclosed methods is an illustration of an example process. Based on design preferences, it should be understood that the specific order or hierarchy of the steps in these methods can be rearranged. The appended method claims present the elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented, unless specifically recited herein.

[0089] Although the aspects of the present invention have been described so far with reference to the accompanying drawings, the above methods, systems, and devices are merely examples, and the scope of the present invention is not limited to these aspects, but is defined only by the appended claims and their equivalents. Various components may be omitted or may be replaced by equivalent components. Additionally, the steps may be implemented in an order different from that described in the present invention. Furthermore, the various components may be combined in various ways. Also, importantly, as technology develops, many of the components described may be replaced by equivalent components that emerge later. Various modifications to the present invention will be apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the scope of the present invention. Thus, the present invention is not limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for accelerating control of a turbofan engine, the method comprising: Use an on-board sensor to measure the operating parameters of the turbofan engine, where the operating parameters include the low-pressure shaft speed of the turbofan engine, the static pressure at the outlet of the high-pressure compressor and the total temperature at the inlet of the high-pressure compressor of the turbofan engine, the high-pressure shaft speed of the turbofan engine, and the engine operating ambient pressure; Determine that the operating state of the turbofan engine enters an acceleration process at least partially based on a comparison of the low-pressure shaft speed with a target speed corresponding to the throttle lever; Calculate the corrected fuel flow rate and the acceleration rate of the turbofan engine and select the smaller value of both the corrected fuel flow rate and the fuel flow rate corresponding to the acceleration rate as the physical fuel flow rate of the turbofan engine, where the corrected fuel flow rate is calculated at least partially based on the static pressure at the outlet of the high-pressure compressor and the total temperature at the inlet of the high-pressure compressor, and the acceleration rate is calculated at least partially based on the high-pressure shaft speed, the total temperature at the inlet of the high-pressure compressor, and the engine operating ambient pressure of the turbofan engine; Determine the acceleration characteristics of the turbofan engine at least partially based on the operating parameters; And Control the acceleration process of the turbofan engine according to the acceleration characteristics and the physical fuel flow rate.

2. The method according to claim 1, characterized in that, The acceleration characteristics include surge or surge precursors, where the surge or surge precursors are determined at least partially based on a comparison of the first-order time derivative of the static pressure at the outlet of the high-pressure compressor with a first threshold value, where controlling the acceleration process of the turbofan engine according to the acceleration characteristics includes: if surge or surge precursors occur, reduce the physical fuel flow rate of the turbofan engine.

3. The method according to claim 1, characterized in that, The operating parameters include the engine exhaust temperature, and the acceleration characteristics include over-temperature or over-temperature precursors, where the over-temperature or over-temperature precursors are determined at least partially based on a comparison of the engine exhaust temperature with a second threshold value, where controlling the acceleration process of the turbofan engine according to the acceleration characteristics includes: if over-temperature or over-temperature precursors occur, reduce the physical fuel flow rate of the turbofan engine.

4. The method according to claim 1, characterized in that, The method further includes: Determine whether air bleed is required for the cabin; and In response to determining that air bleed is required for the cabin, increase the physical fuel flow rate of the turbofan engine.

5. The method according to claim 1, characterized in that, The method further includes: Record the acceleration time of the acceleration process; Compare the acceleration time with a required time; and If the difference between the required time and the acceleration time is less than a third threshold value, bleed air and increase the physical fuel flow rate of the turbofan engine when the engine transient bleed valve is less than a fourth threshold value.

6. The method according to claim 1, characterized in that, The method further includes: Calculate the high-pressure corrected speed based on the high-pressure shaft speed and the total temperature at the inlet of the high-pressure compressor; and Obtain the acceleration rate from a look-up table for the acceleration rate based on the value of the high-pressure corrected speed and the engine operating ambient pressure.

7. A system for accelerating control of a turbofan engine, the system comprising: A parameter measurement module configured to measure operating parameters of the turbofan engine, the operating parameters including the low-pressure shaft speed of the turbofan engine, the static pressure at the outlet of the high-pressure compressor and the total temperature at the inlet of the high-pressure compressor of the turbofan engine, the high-pressure shaft speed of the turbofan engine, and the engine operating ambient pressure; A characteristic determination module configured to: Determine that the operating state of the turbofan engine enters an acceleration process at least partially based on a comparison of the low-pressure shaft speed with a target speed corresponding to the throttle lever, Calculate a corrected fuel flow rate and an acceleration rate of the turbofan engine and select the smaller value of both the corrected fuel flow rate and the fuel flow rate corresponding to the acceleration rate as the physical fuel flow rate of the turbofan engine, wherein the corrected fuel flow rate is calculated at least partially based on the static pressure at the outlet of the high-pressure compressor and the total temperature at the inlet of the high-pressure compressor, the acceleration rate is calculated at least partially based on the high-pressure shaft speed of the turbofan engine, the total temperature at the inlet of the high-pressure compressor, and the engine operating ambient pressure, and Determine the acceleration characteristics of the turbofan engine at least partially based on the operating parameters; And An acceleration control module configured to control the acceleration process of the turbofan engine according to the acceleration characteristics and the physical fuel flow rate.

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