1. A fusion control method of an aircraft engine acceleration control plan comprises the following steps:

s100: fuel flow W from N-dot control planning by power extraction_f，aFuel flow W obtained by converting fuel flow control plan_f，bControl deviation e of₂＝W_f，b-W_f，a；

S200: according to the control deviation e₂Fuel flow W obtained by controlling plan for N-dot_f，aCarrying out first correction to obtain the fuel flow W after the first correction_f，c；

S300: for the fuel oil flow W after the first correction_f，cFuel flow W obtained by converting fuel flow control plan_f，bThe second correction is carried out on the fuel flow of more than 5 percent to obtain the fuel flow W after the second correction_f，accAnd W is_f，accThe fuel output value obtained as the fusion control plan is input to a selector of the aircraft engine.

2. The method according to claim 1, wherein preferably step S200 comprises the steps of:

s201: according to the control deviation e₂Determining real-time adjustment coefficient C of N-dot control plan by nonlinear penalty function designed a priori_N-dot；

S202: according to the real-time adjustment coefficient C_N-dotUpdating the limit control target value of the N-dot control plan to obtain a new acceleration fuel increment delta W_f，c；

S203: for new acceleration fuel increment delta W_f，cFuel flow W corresponding to the output of one cycle of the aircraft engine controller_f，sSumming to obtain the first corrected fuel flow W_f，c。

3. The method according to claim 2, wherein in step S201, the a priori designed non-linear penalty function is expressed as:

wherein f is₁Representing a first non-linear penalty function for the deviation e₂Punishment of N-dot limit control target value f for timing₂Representing a second non-linear penalty function for the deviation e₂Increasing N-dot limit control target value when the voltage is negative, N₂Indicating high-pressure rotor speed, T_stWhich represents the standard atmospheric temperature at sea level,indicating the total intake air temperature.

4. The method according to claim 2, wherein in step S201, the real-time adjustment coefficient C_N-dotExpressed as:

and is

Wherein, C_N-dotReal-time adjustment coefficients for the N-dot control plan for obtaining a corrected target N-dot value, C_N-dotLess than 1 means a decrease in the original target N-dot value, and more than 1 means an increase; k₁To cut sensitive parameters, K₁The larger the value, the steeper the curve, the more obvious the reduction of the target N-dot value, and K₂For low speed correction factor, phi is a function of the relative speed of the high pressure rotor, T_stWhich represents the standard atmospheric temperature at sea level,denotes total intake air temperature, n_2RIndicating the high pressure rotor relative speed.

5. The method according to claim 2, wherein in step S202, the coefficient C is adjusted according to real time_N-dotUpdating the limit control target value of the N-dot control plan is carried out by the following formula:

wherein, Δ W_f，cFor the new increment of acceleration fuel,deriving a target value, W, for the current control plan_f，sFuel flow, Δ W, output for one cycle on the controller_f，aPlanned fuel flow W for N-dot control_f，aAnd controlFuel flow W of one cycle output on the system_f，sG is the correction function of the first correction.

6. The method of claim 5, wherein the first modified modification function g is represented as:

wherein k is_pProportional gain, k, for PID control_iIs the integral gain of the PID control.

7. The method of claim 2, wherein the first corrected fuel flow rate W is determined in step S204_f，cExpressed as:

W_f，c＝ΔW_f，c+W_f，s

wherein, Δ W_f，cFor new acceleration of fuel increment, W_f，sThe fuel flow is output periodically on the controller.

8. The method according to claim, wherein in step S300, the first corrected fuel flow W is_f，cFuel flow W obtained by converting fuel flow control plan_f，bThe second correction of the fuel flow rate of 5% or more is performed by the following formula:

W_f，acc＝W_f，door+h(W_f，c，W_f，lim，W_f，door)

and is

Wherein, W_f，accIndicating the fuel flow after the second correction, W_f，doorThreshold value, W, representing the start of secondary correction of accelerated fuel flow after N-dot plan correction_f，limAnd h represents a correction function of the second correction.

Background

The control plan is a general term for all rules followed by the control system. The method describes the common incidence relation of a plurality of influencing factors such as directly controllable parameters, control target parameters, engine constraint parameters, external environment conditions of the engine, the working state of the engine and the like. The engine is more likely to touch various physical boundaries in the transient state, requiring that the transient state control should ensure good regulation performance without exceeding any physical working limit, while the acceleration process control is typical of the transient state control, the most commonly touched constraint being the limitation of the surge margin of the high pressure compressor. An acceleration control plan, which is commonly referred to in the control of an aircraft engine, is a limit control plan for the acceleration process with respect to the surge margin, and all forms of acceleration processes are subject to the constraints of the plan.

Common acceleration control plans today include an N-dot control plan and a scaled fuel flow control plan. One of the advantages of using the N-dot control plan for controlling the acceleration process is that the acceleration of the engine rotor is ensured, and the acceleration of the high-pressure rotor can be made to track the upper target N-dot value in a closed-loop control mode, and the influence of fuel metering errors is basically avoided. However, the control of the engine acceleration process by adopting the N-dot control plan is easily influenced by the aspects of engine power extraction, performance degradation, bleed air abnormity and the like, so that the engine crosses an actual acceleration surge limit line to approach a stall boundary when being accelerated, and the compressor is induced to stall or surge. The acceleration of the engine is limited and controlled by a converted fuel flow control plan, which is not easily influenced by power extraction, but the converted fuel flow is easily influenced by measurement errors of a sensor, for example, the deviation of the calculation of the accelerated fuel flow is caused by the occurrence of air leakage and air lock of the sensor for measuring the pressure behind an air compressor, besides, the acceleration control adopting the control plan is usually open-loop control, and the inaccuracy of a fuel metering device of an execution mechanism can also cause the deviation between the fuel flow required by a controller and the fuel flow actually input by the engine, thereby finally causing the reduction of the acceleration performance. Therefore, the conventional control plan has certain limitations, and with the further increase of the requirement of the new generation engine on the acceleration process of the control system, a new control plan needs to be designed to meet the requirement.

The method of adopting control plan fusion is an important means for effectively solving the problems, however, the fusion of the control plan and the application in the full envelope are very difficult due to the wide working envelope of the engine and a plurality of influence factors.

The above information disclosed in this background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Disclosure of Invention

Aiming at the defects in the prior art, the purpose of the disclosure is to provide a fusion control method of an aircraft engine acceleration control plan, which can avoid surge caused by power extraction, performance degradation and abnormal change of bleed air in an N-dot control plan.

In order to achieve the above purpose, the present disclosure provides the following technical solutions:

a fusion control method of an aircraft engine acceleration control plan comprises the following steps:

s100: fuel flow W from N-dot control planning by power extraction_f，aFuel flow W obtained by converting fuel flow control plan_f，bControl deviation e of₂＝W_f，b-W_f，a；

S200: according to the control deviation e₂Fuel flow W obtained by controlling plan for N-dot_f，aCarrying out first correction to obtain the fuel flow W after the first correction_f，c；

S300: for the fuel oil flow W after the first correction_f，cFuel flow W obtained by converting fuel flow control plan_f，bThe second correction is carried out on the fuel flow of more than 5 percent to obtain the fuel flow W after the second correction_f，accAnd W is_f，accThe fuel output value obtained as the fusion control plan is input to a selector of the aircraft engine.

Preferably, step S200 includes the steps of:

s201: according to the control deviation e₂Determining real-time adjustment coefficient C of N-dot control plan by nonlinear penalty function designed a priori_N-dot；

S202: according to the real-time adjustment coefficient C_N-dotUpdating the limit control target value of the N-dot control plan to obtain a new acceleration fuel increment delta W_f，c；

S203: for new acceleration fuel increment delta W_f，cFuel flow W corresponding to the output of one cycle of the aircraft engine controller_f，sSumming to obtain the first corrected fuel flow W_f，c。

Preferably, in step S201, the a priori designed non-linear penalty function is expressed as:

wherein f is₁Representing a first non-linear penalty function for the deviation e₂Punishment of N-dot limit control target value f for timing₂Representing a second non-linear penalty function for the deviation e₂Increasing N-dot limit control target value when the voltage is negative, N₂Indicating high-pressure rotor speed, T_stWhich represents the standard atmospheric temperature at sea level,is shown inThe total temperature of qi.

Preferably, in step S201, the real-time adjustment coefficient C is adjusted_N-dotExpressed as:

and is

Wherein, C_N-dotReal-time adjustment coefficients for the N-dot control plan for obtaining a corrected target N-dot value, C_N-dotLess than 1 means a decrease in the original target N-dot value, and more than 1 means an increase; k₁To cut sensitive parameters, K₁The larger the value, the steeper the curve, the more obvious the reduction of the target N-dot value, and K₂For low speed correction factor, phi is a function of the relative speed of the high pressure rotor, T_stWhich represents the standard atmospheric temperature at sea level,denotes total intake air temperature, n_2RIndicating the high pressure rotor relative speed.

Preferably, in step S202, the coefficient C is adjusted according to real time_N-dotUpdating the limit control target value of the N-dot control plan is carried out by the following formula:

wherein, Δ W_f，cFor the new increment of acceleration fuel,deriving a target value, W, for the current control plan_f，sFuel flow, Δ W, output for one cycle on the controller_f，aPlanned fuel flow W for N-dot control_f，aFuel oil periodically output from controllerFlow rate W_f，sG is the correction function of the first correction.

Preferably, the first modified modification function g is represented as:

wherein k is_pProportional gain, k, for PID control_iIs the integral gain of the PID control.

Preferably, in step S204, the fuel flow W after the first correction_f，cExpressed as:

W_f，c＝ΔW_f，c+W_f，s

wherein, Δ W_f，cFor new acceleration of fuel increment, W_f，sThe fuel flow is output periodically on the controller.

Preferably, in step S300, the first corrected fuel flow W is_f，cFuel flow W obtained by converting fuel flow control plan_f，bThe second correction of the fuel flow rate of 5% or more is performed by the following formula:

W_f，acc＝W_f，door+h(W_f，c，W_f，lim，W_f，door)

and is

Wherein, W_f，doorThreshold value, W, representing the start of secondary correction of accelerated fuel flow after N-dot plan correction_f，limAnd h represents a correction function of the second correction.

Compared with the prior art, the beneficial effect that this disclosure brought does:

1. the acceleration process controlled by the method can avoid surging of an N-dot control plan caused by power extraction, performance decline and abnormal change of air entraining, the acceleration time is always superior to or equivalent to a converted fuel flow control plan, and the early falling of the rotating speed caused by an air pressure sensor and fuel metering error can be counteracted to a certain degree;

2. the acceleration process controlled by the method can bear the widest range of power extraction, air-entraining change, air pressure sensor and fuel metering error, and has the best robustness;

3. the method disclosed by the invention can better adapt to the requirement of acceleration work in the full-flight envelope range.

Drawings

FIG. 1 is a flow chart of a method for fusion control of an aircraft engine acceleration control plan according to an embodiment of the present disclosure;

FIG. 2 is a randomly generated operating point within a flight envelope provided by one embodiment of the present disclosure;

FIG. 3 is a graph of acceleration times for different envelope points for a fusion control and scaled fuel control schedule provided by an embodiment of the present disclosure;

FIG. 4 is a graph of stall points within a flight envelope for an N-dot control plan control under perturbed operating conditions provided by one embodiment of the present disclosure;

FIG. 5 is a graph illustrating a fusion control and scaled fuel control plan map for acceleration times at different envelope points during a perturbed operating condition according to one embodiment of the present disclosure;

FIG. 6 is a graph of power draw magnitude versus time provided by one embodiment of the present disclosure;

FIG. 7 is an acceleration line of an N-dot control plan provided by one embodiment of the present disclosure;

FIG. 8 is a plot of high pressure rotor relative speed for a scaled fuel flow control schedule control provided by an embodiment of the present disclosure;

FIG. 9 is a high pressure rotor relative speed curve controlled by a fused control plan provided by one embodiment of the present disclosure;

FIG. 10 is a graph comparing power draw capabilities of 3 control schemes in a particular environment provided by one embodiment of the present disclosure;

FIG. 11 is a power draw comparison graph of 3 control plans that account for bleed air and sensor errors or fuel metering errors provided by one embodiment of the present disclosure;

FIG. 12 is a spatial range of sensor or fuel metering errors and bleed air quantities over N-dot for a fused control plan provided by one embodiment of the present disclosure;

13(a), 13(b) are graphs of minimum surge margin of the acceleration process under the control of a fusion control plan and an N-dot control plan respectively provided by an embodiment of the present disclosure;

FIG. 14 is a statistical histogram of surge margin under separate control of a fused control plan and an N-dot control plan provided by one embodiment of the present disclosure;

15(a), 15(b) are acceleration time differences for the converted fuel flow control plan and the fused control plan control provided by one embodiment of the present disclosure;

FIG. 16 is a statistical histogram of acceleration time differences for the scaled fuel flow control plan and the fused control plan controls provided by one embodiment of the present disclosure.

Detailed Description

Specific embodiments of the present disclosure will be described in detail below with reference to fig. 1 to 16. While specific embodiments of the disclosure are shown in the drawings, it should be understood that the disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

It should be noted that certain terms are used throughout the description and claims to refer to particular components. As one skilled in the art will appreciate, various names may be used to refer to a component. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. The description which follows is a preferred embodiment of the invention, but is made for the purpose of illustrating the general principles of the invention and not for the purpose of limiting the scope of the invention. The scope of the present disclosure is to be determined by the terms of the appended claims.

To facilitate an understanding of the embodiments of the present disclosure, the following detailed description is to be considered in conjunction with the accompanying drawings, and the drawings are not to be construed as limiting the embodiments of the present disclosure.

In one embodiment, as shown in fig. 1, a method for fusion control of an aircraft engine acceleration control plan includes the following steps:

s100: fuel flow W from N-dot control planning by power extraction_f，aFuel flow W obtained by converting fuel flow control plan_f，bControl deviation e of₂＝W_f，b-W_f，a；

S200: according to the control deviation e₂Fuel flow W obtained by controlling plan for N-dot_f，aCarrying out first correction to obtain the fuel flow W after the first correction_f，c；

S300: for the fuel oil flow W after the first correction_f，cFuel flow W obtained by converting fuel flow control plan_f，bThe second correction is carried out on the fuel flow of more than 5 percent to obtain the fuel flow W after the second correction_f，accAnd W is_f，accThe fuel output value obtained as the fusion control plan is input to a selector of the aircraft engine.

The embodiment forms a complete technical scheme of the method, the acceleration process controlled by the method can avoid surging of an N-dot control plan caused by power extraction, performance decline and abnormal change of air entrainment, the acceleration time is always superior to or equivalent to a converted fuel flow control plan, and the early falling of the rotating speed caused by an air pressure sensor and a fuel metering error can be counteracted to a certain degree; in addition, the acceleration process controlled by the method can bear the widest range of errors of power extraction, air-entraining change, air pressure sensor and fuel metering, and has the best robustness.

In another embodiment, step S200 includes the steps of:

s201: according to control biasDifference e₂Determining real-time adjustment coefficient C of N-dot control plan by nonlinear penalty function designed a priori_N-dot；

S202: according to the real-time adjustment coefficient C_N-dotUpdating the limit control target value of the N-dot control plan to obtain a new acceleration fuel increment delta W_f，c；

S203: for new acceleration fuel increment delta W_f，cFuel flow W corresponding to the output of one cycle of the aircraft engine controller_f，sSumming to obtain the first corrected fuel flow W_f，c。

In another embodiment, in step S201, the a priori designed non-linear penalty function is expressed as:

wherein f is₁Representing a first non-linear penalty function for the deviation e₂Punishment of N-dot limit control target value f for timing₂Representing a second non-linear penalty function for the deviation e₂Increasing N-dot limit control target value when the voltage is negative, N₂Indicating high-pressure rotor speed, T_stWhich represents the standard atmospheric temperature at sea level,indicating the total intake air temperature.

In another embodiment, in step S201, the real-time adjustment coefficient C is adjusted_N-dotExpressed as:

wherein, C_N-dotReal-time adjustment coefficients for the N-dot control plan for obtaining a corrected target N-dot value, C_N-dotLess than 1 represents subtractionA small original target N-dot value, greater than 1, indicates an increase; k₁To cut sensitive parameters, K₁The larger the value, the steeper the curve, the more pronounced the reduction in the target N-dot value.

In this embodiment, in order to maintain the simplicity, uniformity, and continuity of the penalty function form, a correction force for enhancing the low rotation speed is selected, and the obtained adjustment coefficient is:

wherein, K₂For low speed correction factor, phi is a function of the relative speed of the high pressure rotor, T_stWhich represents the standard atmospheric temperature at sea level,denotes total intake air temperature, n_2RIndicating the high pressure rotor relative speed.

In another embodiment, the adjusting of the coefficient C in real time is based on_N-dotUpdating the limit control target value of the N-dot control plan is carried out by the following formula:

wherein, Δ W_f，cFor the new increment of acceleration fuel,deriving a target value, W, for the current control plan_f，sFuel flow, Δ W, output for one cycle on the controller_f，aPlanned fuel flow W for N-dot control_f，aFuel flow W corresponding to a cycle output on the controller_f，sG is the correction function of the first correction.

In another embodiment, the first modified modification function g is represented by:

wherein k is_pProportional gain, k, for PID control_iIs the integral gain of the PID control.

In another embodiment, in step S204, the first corrected fuel flow W_f，cExpressed as:

W_f，c＝ΔW_f，c+W_f，s

wherein, Δ W_f，cFor new acceleration of fuel increment, W_f，sThe fuel flow is output periodically on the controller.

In another embodiment, the first corrected fuel flow rate W is_f，cFuel flow W obtained by converting fuel flow control plan_f，bThe second correction of the fuel flow rate of 5% or more is performed by the following formula:

W_f，acc＝W_f，door+h(W_f，c，W_f，lim，W_f，door)

and is

Wherein, W_f，doorThreshold value, W, representing the start of secondary correction of accelerated fuel flow after N-dot plan correction_f，limAnd h represents a correction function of the second correction.

In the following, the two control plans of the present disclosure are compared with the acceleration process controlled by the N-dot control plan and the converted fuel flow control plan alone to check the characteristics of the method of the present disclosure, and the specific process is as follows:

assuming that the state of the engine in the flight envelope is continuously changed, 1500 groups of working points are randomly generated in the range of the Mach number and the altitude of the flight envelope, the engine is sequentially flown to the corresponding working points to repeatedly carry out the whole-course acceleration from the 15-degree throttle rod to the 65-degree throttle rod, and whether the acceleration process exceeds a stall boundary or not is recorded and observed, wherein the working points generated by simulation are shown in FIG. 2. Simulation results show that three acceleration control modes can not touch stall boundaries in the acceleration process of the working points, and basically can be considered to have the working capacity of adapting to the full envelope range, the average acceleration time of the two control plan fusion control modes and the N-dot control plan single control mode is 4.4s, and the average acceleration time of the fuel flow control plan is converted into 4.6s, wherein the distribution of the acceleration time of different envelope points of the fusion control plan and the converted fuel control plan is shown in figure 3, and no obvious difference can be seen. In fig. 3, Δ t represents the acceleration time saved by the two control plan fusion controls, which is equal to the converted fuel control plan acceleration time minus the former acceleration time.

When the engine keeps a group of disturbed working states of 80kW of power extraction, minus 2.5 percent of fuel metering error, 2.5 percent of bleed air, 99 percent of compressor and turbine efficiency decline to leave factory and 99 percent of compressor flow capacity decline to leave factory, results in 1500 groups of flight envelope curves of re-simulation calculation show that 8.7 percent of working points of N-dot control plan control exceed a stall boundary, and points exceeding the stall boundary are mainly concentrated on the left boundary in the air, as shown in figure 4. The average acceleration time of the two control plans is 5.3s, the average acceleration time of the converted fuel flow control plan is 6.3s, the acceleration time distribution of the two control plans is shown in figure 5, according to the standard requirement of JSSG-2007B, the whole-course acceleration time in a covered line does not exceed 12s, the maximum acceleration time in the figure 3 does not exceed 12s when no work disturbance exists, and under the disturbance condition, the maximum acceleration time of the fusion control is about 12s, the converted fuel acceleration time is 15.5s, which indicates that the fusion control can still meet the requirement of the acceleration time under the small disturbance condition. Therefore, the mode of the fusion control of the two control plans under the same working condition is better than the acceleration control mode of a single control plan in the flight envelope on the whole.

Further, the present disclosure also explains the robustness degree of the control of the two control plans by comparing the fusion control of the two control plans with the control of the N-dot control plan and the converted fuel flow control plan separately through simulation, and the specific process is as follows:

the acceleration conditions of the engine model under three different acceleration control modes are observed by adding disturbance of air entrainment, power extraction, air pressure sensor error and fuel metering error to a certain degree: suppose the engine is slowing down from the ground to n_2RThere was a power draw of 500kW during steady state at 0.93, drawing 2% air flow,the gas pressure sensor and the fuel metering device have errors of-4% and-6%, respectively, and these disturbances are injected into the engine from the time of accelerating the accelerator lever, the sensor and fuel metering errors are step signals, the maximum change of the air flow is limited to 1% in a single step, and the change is punished and limited after the single step change of the power extraction exceeds 14kW, as shown in fig. 6, a curve of the injection power extraction size along with the change of the time.

Simulation calculations can find that the stall boundary of the compressor is broken through just before the acceleration process controlled by the N-dot control plan is started, as shown in FIG. 7. The acceleration process controlled by the converted fuel flow control plan cannot reach the actual acceleration limit line due to the influence of the metering errors of the sensor and the actuator, and the provided accelerated fuel flow is even smaller than the fuel flow required for maintaining the steady-state operation, so that the rotor speed is reduced, as shown in the speed response curve of fig. 8. Both of the above control plans cannot perform normal acceleration under the working condition, but the method of fusing the two control plans used herein can still perform the acceleration process safely, as shown in fig. 9, which is a high-pressure rotor speed response curve for controlling the acceleration process, and finally accelerates to the target speed. Therefore, the disturbed ranges of the three control modes for realizing safe acceleration are obviously different.

If other working conditions are controlled to be unchanged, when the power extraction magnitude in the acceleration process is only changed, the power range which can be extracted by the three control modes is shown in figure 10, and the N-dot control plan independently controls the power extraction of the acceleration process exceeding 196kW to cross the stalling boundary of the compressor; the problem that the power extraction exceeds 430kW in the acceleration process of converting the fuel flow control plan control is faced with the rotating speed; the result of controlling the fusion method of the two control plans is that the rotating speed is reduced only when the rotating speed exceeds 569kW, which shows that the method compensates the influence of measurement errors to a certain extent while ensuring the acceleration safety, so that the amplitude of the acceleration time extension is as small as possible. As shown in fig. 11, the maximum value of the extractable power in the acceleration control process is obtained by three acceleration control methods under different sensor or fuel metering errors and different air entrainment amounts, and it can be found that the extractable power range of the two control plan fusion control methods is always the widest under the conditions of smaller error and abnormal air entrainment, in other words, the tolerable sensor and fuel metering error is the largest under the same power extraction and air entrainment amounts, so that the two control plan fusion control methods have the best robustness and the strongest disturbance resistance. As shown in the dark area of fig. 12, the spatial range of the sensor or fuel metering error and the bleed air amount of the two control plan fusion control modes, which have better power extraction capability than the N-dot, is approximated to a linear boundary, and it can be seen that the former has certain advantages under the small error and small bleed air amount range centered on the normal working condition.

Furthermore, the method compares the two control plans in a fusion mode with the control of the surge margin in the acceleration process by independently adopting the N-dot control plan and the converted fuel flow control plan, and comprises the following specific processes:

and verifying the advantages and disadvantages of the acceleration process under the same three control modes by randomly extracting 1000 disturbance working conditions. It is assumed that besides power extraction, bleed air, sensor and fuel metering errors, the influence of engine performance degradation is also considered, as shown in table 1, the verification value range of each disturbance is provided, and each operational disturbance is assumed to satisfy uniform distribution, i.e. the engine is in an abnormal condition probability space. Random numbers in a corresponding range are generated to serve as a group of accelerating working conditions of the turbofan engine, the engine is accelerated and compared in three control modes respectively, the power extraction capacities of the engine at different envelope points are different, comparison and verification are facilitated, and the accelerating process is the whole-process accelerating from ground slow turning to a middle state.

TABLE 1

Simulation verification records the minimum surge margin in the three control plan acceleration processes, and the minimum surge margin in the acceleration process under 1000 groups of working conditions is shown in fig. 13(a), wherein fig. 13(b) is a partial enlarged view of fig. 13(a), it can be seen that the surge margin of the N-dot control plan control acceleration process is reduced as a whole under different severe working conditions, and the surge margin of the two control plan fusion control modes is still near the designed acceleration limit line, wherein the upper dotted line is the original acceleration limit line, and the lower part is the stall boundary. The statistics of 1000 working conditions show that: the N-dot control plan controls that the acceleration process crosses 66.8% of the stalling boundary of the compressor, and the fused control mode crosses 0% of the stalling boundary, which shows that the later effectively avoids the possibility of surge. FIG. 14 shows statistical histograms of surge margins under two control modes, where the N-dot control plan only reserves the portion that is still accelerated in the stable operating region, and it can be seen that the whole N-dot control plan is close to the unstable operating region, and a wider distribution range shows that the N-dot control plan is more susceptible to disturbance of power extraction; most of the surge margin of the two control plan fusion control modes is still close to the designed acceleration limit line, and the safety can be guaranteed better than that of the N-dot control plan. As shown in fig. 15(a) and 15(b), after all the rotation speed drop conditions are eliminated in the 1000 groups, the acceleration time difference of the two control plans is converted, and the acceleration time after the two control plans are integrated is smaller than that of the converted fuel flow control plan. Through statistics, the fuel flow control plan is converted to account for 9.8% of the speed drop in the acceleration process, the two plans are only in a fusion control mode of 1.6%, and no case of the latter crosses a stall boundary, so that the latter can effectively avoid the speed drop caused by the measurement error of a sensor, and meanwhile, normal suspension and speed drop during the extraction of excessive power are allowed, and the possibility of surge is further prevented. Fig. 16 shows the distribution of the time difference between the acceleration time of the acceleration process of the converted fuel flow control plan under the same operating conditions and the two plan fusion control modes, in which the acceleration time under almost all operating conditions is better than the converted fuel flow control plan, the average saving time is about 1.5s, and the maximum saving time is about 21s, which indicates that the two plan fusion control modes can reduce the acceleration time extension caused by the sensor error and have sufficient compatibility for the extreme case where the acceleration capability is suddenly reduced.

The foregoing describes the general principles of the present disclosure in conjunction with specific embodiments, however, it is noted that the advantages, effects, etc. mentioned in the present disclosure are merely examples and are not limiting, and they should not be considered essential to the various embodiments of the present disclosure. Furthermore, the foregoing disclosure of specific details is for the purpose of illustration and description and is not intended to be limiting, since the foregoing disclosure is not intended to be exhaustive or to limit the disclosure to the precise details disclosed.