Turboshaft engine control method and system based on incremental double-rotating-speed closed loop, turboshaft engine and vehicle

Abstract

The invention relates to a turboshaft engine control method and system based on an incremental double-rotating-speed closed loop, a turboshaft engine and a vehicle, and belongs to the technical field of engine control. Gain compensation based on power turbine load sampling is introduced in the Np control link of the turboshaft engine, so that the calculation precision of a gas turbine rotating speed given value is improved; ng speed and acceleration parallel control is introduced in the Ng control link, a tracking differentiator is further introduced to remove Ng sampling noise to obtain a more accurate Ng acceleration sampling value, a first fuel oil increment and a second fuel oil increment are obtained through incremental PID control calculation, one of the first fuel oil increment and the second fuel oil increment is selected on the basis of the actual working condition of an engine, and therefore the control accuracy of the engine is improved. The problems that an existing turboshaft engine control method is poor in heavy load change and complex disturbance adjusting effect and poor in self-adaptability and robustness are solved, and the invention further provides a turboshaft engine control method adopting the control method, a turboshaft engine and a vehicle.

Description

Technical Field

[0001] The present invention relates to the field of engine control technology, and in particular to a turboshaft engine control method and system based on an incremental dual-speed closed loop, a turboshaft engine and a vehicle. Background Art

[0002] Vehicles using turboshaft engines generally have large load link inertia, complex external disturbances, and delayed engine combustion. Taking helicopters as an example, once load or disturbance changes occur, in order to avoid the helicopter rotor speed becoming unstable due to changes in load or disturbance, the turboshaft engine control system should be able to quickly respond to changes in rotor load or disturbance within the required time.

[0003] Turboshaft engine speed control usually adopts control methods such as single-loop control and cascade loop control. Among them, the current common cascade loop control can only meet specific load and disturbance change requirements, and has poor regulation effect on large load changes and complex disturbances. The control system's adaptability and robustness are not good. Summary of the invention

[0004] In view of the above analysis, the embodiments of the present invention aim to provide a turboshaft engine control method, system, turboshaft engine and vehicle based on an incremental dual-speed closed loop, so as to solve the problems that the existing turboshaft engine control has poor regulation effect in dealing with large load changes and complex disturbances, and poor adaptability and robustness.

[0005] On the one hand, an embodiment of the present invention provides a turboshaft engine control method based on an incremental dual-speed closed loop, the method specifically comprising:

[0006] The gas turbine output speed, the power turbine output speed, and the power turbine load signal are sampled respectively to obtain a gas turbine speed sampling value, a power turbine speed sampling value, and a power turbine load signal sampling value;

[0007] A gas turbine speed set value is obtained based on a difference between a speed control instruction and the power turbine speed sampling value and a power turbine load signal sampling value;

[0008] Based on the difference between the gas turbine speed set value and the gas turbine speed sampling value, a gas turbine acceleration planning value and a first fuel increment are calculated respectively, and based on the gas turbine speed sampling value, a gas turbine acceleration limit value and a gas turbine acceleration sampling value are calculated;

[0009] Calculating a gas turbine acceleration given value based on a smaller value of the gas turbine acceleration planning value and the gas turbine acceleration limit value;

[0010] Calculating a second fuel increment based on a difference between the gas turbine acceleration set value and the gas turbine acceleration sampling value;

[0011] The first fuel increment or the second fuel increment is selected based on the current operating condition of the engine, and is added to the fuel flow of the previous cycle to obtain the given fuel flow of the current cycle.

[0012] The beneficial effects of the above technical solution are as follows: the power output of each link of the turboshaft engine is obtained by sampling the gas turbine output speed, the power turbine output speed, and the power turbine load signal, and the gas turbine speed given value is calculated based on the power turbine speed sampling value and the power turbine load signal sampling value to achieve accurate calculation of the expected output of the gas turbine speed; the gas turbine acceleration planning value and the first fuel increment are calculated based on the difference between the gas turbine speed given value and the gas turbine speed sampling value, the gas turbine acceleration limit value and the gas turbine acceleration sampling value are calculated based on the gas turbine acceleration sampling value, and the gas turbine acceleration planning value and the gas turbine acceleration sampling value are calculated based on the gas turbine acceleration planning value and the gas turbine acceleration sampling value. The gas turbine acceleration given value is calculated based on the smaller value of the limit value, which is more accurate than the gas turbine acceleration given value obtained by only considering the gas turbine acceleration limit value in the prior art; the second fuel increment is calculated based on the difference between the gas turbine acceleration given value and the gas turbine acceleration sampling value, which takes more comprehensive consideration of the factors affecting the gas turbine than the fuel increment calculated based only on the gas turbine speed sampling in the prior art; and then the first fuel increment or the second fuel increment is selected based on the current operating condition of the engine, which achieves more accurate calculation and output of the fuel increment compared to the prior art, thereby achieving more accurate control of the turboshaft engine and improving the turboshaft engine's ability to cope with sudden changes and its adaptability.

[0013] Based on the further improvement of the above method, the difference between the speed control instruction and the power turbine speed sampling value and the power turbine load signal sampling value is used to obtain the gas turbine speed set value by the following method, and the method specifically includes:

[0014] The gas turbine speed set value deviation is calculated based on the difference between the speed control instruction and the power turbine speed sampling value;

[0015] Based on the power turbine load signal sampling value, a current period gas turbine speed feedforward value is obtained by interpolating the power turbine load characteristic curve;

[0016] Calculating the load signal change rate of the current cycle, determining whether the load signal change rate of the current cycle is greater than a preset threshold, and if so, performing gain compensation on the gas turbine speed feedforward value of the current cycle;

[0017] The gas turbine speed set value is obtained by adding the gas turbine speed set value deviation and the current period gas turbine speed feedforward value.

[0018] The beneficial effects of the above-mentioned further improvement scheme are: based on the speed control instruction and the power turbine speed sampling value, the power turbine speed deviation can be calculated, and then based on the power turbine speed deviation calculation, the gas turbine speed set value deviation can be obtained; the current cycle gas turbine speed feedforward value is obtained by applying the power turbine load signal sampling value to the power turbine load characteristic curve for difference calculation, and then by calculating the current cycle power turbine load signal change rate, and judging whether the current cycle gas turbine speed feedforward value needs to be gain compensated based on a preset threshold. The purpose of this technical process is to obtain a more accurate current cycle gas turbine speed feedforward value, so that the gas turbine speed set value deviation and the current cycle gas turbine speed feedforward value are added to obtain a more accurate gas turbine speed set value, which is helpful to achieve more precise control of the turboshaft engine.

[0019] Based on the further improvement of the above method, the load gain compensation for the current cycle gas turbine speed feedforward value specifically refers to obtaining a gain coefficient by interpolating the load gain curve based on the current cycle load signal change rate, and then taking the product of the current cycle gas turbine speed feedforward value and the gain coefficient as the compensated current cycle gas turbine speed feedforward value.

[0020] The beneficial effect of the above further improvement scheme is that an accurate gain coefficient can be obtained, and then gain compensation is performed on the current period gas turbine speed feedforward value based on the gain coefficient.

[0021] Based on the further improvement of the above method, the gas turbine acceleration planning value is calculated based on the difference between the gas turbine speed given value and the gas turbine speed sampling value, specifically refers to looking up the engine nonlinear planning table based on the difference between the gas turbine speed given value and the gas turbine speed sampling value and performing interpolation calculation to obtain the gas turbine acceleration planning value.

[0022] The beneficial effect of the above further improvement scheme is that an accurate gas turbine acceleration planning value can be obtained.

[0023] Based on the further improvement of the above method, the first fuel increment is calculated based on the difference between the gas turbine speed set value and the gas turbine speed sampling value, and the second fuel increment is calculated based on the difference between the gas turbine acceleration set value and the gas turbine acceleration sampling value. Both use an incremental PID control calculation method, and the method is specifically expressed as the following formula:

[0024] ΔWf=Kp×[ΔD(k)-ΔD(k-1)]+Ki×ΔD(k)+Kd×[ΔD(k)-2ΔD(k-1)+ΔD(k-2)], where,

[0025] ΔWf is the first fuel increment / the second fuel increment,

[0026] Kp is the corresponding proportionality coefficient,

[0027] Ki is the corresponding integration coefficient,

[0028] Kp is the corresponding differential coefficient,

[0029] ΔD(k) is the difference between the gas turbine speed set value and the gas turbine speed sampling value in the current cycle / the difference between the gas turbine acceleration set value and the gas turbine acceleration sampling value in the current cycle, where k is the current cycle.

[0030] The beneficial effect of the above-mentioned further improvement scheme is: the first fuel increment is calculated based on the difference between the gas turbine speed set value and the gas turbine speed sampling value in the current period through an incremental PID algorithm, and the second fuel increment is calculated based on the difference between the gas turbine acceleration set value and the gas turbine acceleration sampling value in the current period. Compared with the existing technology, it is more suitable for gas turbine acceleration and speed-related parameter calculations, and can obtain more accurate calculation results than the existing technology.

[0031] Based on a further improvement of the above method, the selecting the first fuel increment or the second fuel increment based on the current operating condition of the engine specifically includes:

[0032] determining whether the current working state of the engine is in an acceleration state, and if so, selecting the larger value of the first fuel increment and the second fuel increment,

[0033] Otherwise, the smaller value between the first fuel increment and the second fuel increment is selected.

[0034] The beneficial effect of the above further improvement scheme is: the first fuel increment or the second fuel increment is selected based on the current operating condition of the engine, so that the selected fuel increment is more adapted to the current operating condition of the engine, which helps to achieve more precise control of the engine.

[0035] On the other hand, an embodiment of the present invention provides a turboshaft engine control system based on an incremental dual-speed closed loop, the control system comprising a power turbine speed controller, a gas turbine speed acceleration and speed parallel controller, a metering valve, and a tracking differentiator, wherein:

[0036] The power turbine speed controller is used to obtain a gas turbine speed given value based on a speed control instruction, a power turbine speed sampling value, and a power turbine load sampling value, and output it to the gas turbine speed acceleration and speed parallel controller;

[0037] The tracking differentiator outputs a gas turbine acceleration sampling value based on the gas turbine speed sampling value;

[0038] The gas turbine speed acceleration and speed parallel controller is used to output the current cycle given fuel flow to the metering valve based on the gas turbine speed given value, the gas turbine acceleration sampling value, and the gas turbine speed sampling value;

[0039] The metering valve is used to adjust the opening of the metering valve based on the difference between the current cycle given fuel flow and the real-time sampling value of the output fuel flow until the output fuel flow is equal to the current cycle given fuel flow.

[0040] The beneficial effects of the above technical solution are as follows: a system for realizing precise control of a turboshaft engine is provided, wherein the N p The controller obtains a gas turbine speed given value based on the speed control instruction, the power turbine speed sampling value, and the power turbine load sampling value, and inputs it into the gas turbine speed acceleration and speed parallel controller, which helps the gas turbine speed acceleration and speed parallel controller to calculate a more accurate result; the gas turbine speed acceleration and speed parallel controller has not been used in the prior art, and the gas turbine speed acceleration and speed parallel controller and the tracking differentiator form a closed-loop feedback, which can calculate a more accurate current cycle given fuel flow and input it to the metering valve, and the metering valve adjusts the metering valve opening based on the difference between the current given fuel flow and the real-time sampling value of the output fuel flow, thereby achieving faster and more accurate regulation of the turboshaft engine fuel compared with the prior art, which helps to improve the regulation ability and adaptability of the turboshaft engine to cope with large load changes and complex disturbances, and based on the real-time sampling of the turboshaft engine gas turbine output, power turbine output, and load and the real-time feedback regulation inner loop control law formed by the gas turbine speed acceleration and speed parallel controller and the tracking differentiator, it has better system robustness.

[0041] Based on the further improvement of the above system, the gas turbine speed acceleration and speed parallel controller includes a gas turbine speed controller, a gas turbine speed acceleration controller, and an integrated voter, wherein:

[0042] The gas turbine speed controller generates a first fuel increment based on the difference between the gas turbine speed set value and the gas turbine speed sampling value and outputs the first fuel increment to the integrated voter.

[0043] The gas turbine speed acceleration controller generates a second fuel increment based on the difference between the gas turbine speed set value and the gas turbine speed sampling value and the gas turbine speed sampling value, and outputs the second fuel increment to the integrated voter.

[0044] The integrated voter determines to select the first fuel increment or the second fuel increment based on the engine operating conditions and obtains the given fuel amount of the current cycle based on the selected fuel increment.

[0045] The beneficial effect of adopting the above-mentioned further improvement scheme is: a gas turbine speed acceleration controller is provided in parallel with the speed controller, and a first fuel increment is obtained based on the difference between the gas turbine speed set value and the gas turbine speed sampling value, and a second fuel increment is obtained based on the difference between the gas turbine speed set value and the gas turbine speed sampling value and the gas turbine speed sampling value, and then the controller of the first fuel increment or the second fuel increment is selected based on the engine operating condition through the comprehensive voter. Compared with the prior art, more accurate calculation and output of the fuel increment is achieved, which helps to achieve more accurate control of the turboshaft engine and enhance the turboshaft engine's ability to cope with sudden changes and adaptability.

[0046] An embodiment of the present invention also provides a turboshaft engine based on incremental dual-speed closed-loop control, the turboshaft engine comprising an engine body, and the turboshaft engine control system based on incremental dual-speed closed-loop provided by an embodiment of the present invention, wherein the control system obtains the current cycle fuel flow based on the gas turbine speed sampling value, the power turbine speed sampling value, the load signal sampling value, and the real-time sampling value of the output fuel flow, and outputs fuel to the engine body according to the current cycle fuel flow.

[0047] The beneficial effects of the above technical solution are as follows: the turboshaft engine including the turboshaft engine control system based on the incremental dual-speed closed loop provided in the embodiment of the present invention has better adjustment capability and adaptability in the face of large load changes and complex disturbances compared to existing turboshaft engines.

[0048] An embodiment of the present invention also provides a vehicle, which includes an operation control system, and a turboshaft engine based on incremental dual-speed closed-loop control provided in the embodiment of the present invention; the operation control system issues a speed control instruction to the turboshaft engine, and the turboshaft engine generates corresponding power and operates based on the speed control instruction.

[0049] The beneficial effects of the above technical solution are as follows: a vehicle using a turboshaft engine based on incremental dual-speed closed-loop control provided by an embodiment of the present invention has better adjustment capabilities in the face of large load changes and complex disturbances and is easier to control.

[0050] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The accompanying drawings are only used for the purpose of illustrating specific embodiments and are not to be considered as limiting the present invention. In the entire drawings, the same reference symbols represent the same components;

[0052] Figure 1 This is a control principle diagram of Example 1 of the present invention.

[0053] Figure 2 This is a structural diagram of the control system of Example 2 of the present invention. DETAILED DESCRIPTION

[0054] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0055] For ease of understanding, the Chinese terms corresponding to the abbreviations appearing in the technical solution of the present invention are listed below, specifically including:

[0056] N p : Power turbine speed, can also represent the power turbine speed sampling value.

[0057] N g : Gas turbine speed.

[0058] CLP: Power turbine load, also known as collective pitch.

[0059] PID: Proportional-Integral-Derivative control.

[0060] N g cmd: Gas turbine speed setpoint.

[0061] N p cmd: Power turbine speed set value, also known as speed control instruction.

[0062] N g clp: Gas turbine speed feedforward value.

[0063] N g S: Gas turbine speed sampling value.

[0064] TD: Tracking Differentiator.

[0065] N g dot: Gas turbine acceleration.

[0066] N g dotS: Gas turbine acceleration sampling value.

[0067] △N g cmd: Gas turbine speed setpoint deviation.

[0068] △N g : Gas turbine speed deviation.

[0069] △N g dot: Gas turbine speed acceleration deviation.

[0070] Embodiment 1:

[0071] A specific embodiment of the present invention discloses a turboshaft engine control method based on an incremental dual-speed closed loop, such as Figure 1 shown.

[0072] The method specifically comprises:

[0073] S1: sampling the gas turbine output speed, the power turbine output speed, and the power turbine load signal respectively to obtain a gas turbine speed sampling value, a power turbine speed sampling value, and a power turbine load signal sampling value;

[0074] S2: Obtaining a gas turbine speed given value based on a difference between a speed control command and the power turbine speed sampling value and a power turbine load signal sampling value;

[0075] S3: calculating the gas turbine acceleration planning value and the first fuel increment based on the difference between the gas turbine speed given value and the gas turbine speed sampling value, and calculating the gas turbine acceleration limit value and the gas turbine acceleration sampling value based on the gas turbine speed sampling value;

[0076] S4: Calculating a gas turbine acceleration given value based on the smaller value of the gas turbine acceleration planning value and the gas turbine acceleration limit value;

[0077] S5: Calculating a second fuel increment based on a difference between the gas turbine acceleration given value and the gas turbine acceleration sampling value;

[0078] S6: Selecting the first fuel increment or the second fuel increment based on the current operating condition of the engine, and adding the first fuel increment to the fuel flow rate of the previous cycle to obtain the given fuel flow rate of the current cycle.

[0079] For various types of vehicles using turboshaft engines, after the turboshaft engines are started and start running, when the vehicles using turboshaft engines start running, for example, the helicopter rotors start rotating to generate lifting power, driving the helicopter to start taking off; or the ship or warship propellers start rotating to drive the ship or warship to start sailing; or the vehicle blades start rotating to generate power to drive the vehicle to start moving forward, then the gas turbine speed, power turbine speed, power turbine load signal, and fuel flow of the turboshaft engine all start generating output values, and the turboshaft engine control method based on the incremental dual-speed closed loop disclosed in this embodiment is applied to perform periodic control on the turboshaft engine.

[0080] Specifically, in step S1, the corresponding sensors of the gas turbine output speed, the power turbine output speed, and the power turbine load signal are sampled by the existing hardware acquisition circuit to obtain the gas turbine speed sampling value N g S, power turbine speed sampling value N p , power turbine load signal sampling value CLP.

[0081] Specifically, Figure 1 As shown, step S2 executes N p control, that is, the speed control command N p cmd and the power turbine speed sampling value N p The difference between the power turbine load signal sampling value CLP and the gas turbine speed given value N is obtained by the following method. g cmd, specifically including;

[0082] S21: Calculate the gas turbine speed set value deviation based on the difference between the speed control instruction and the power turbine speed sampling value.

[0083] Specifically, the relay control instruction N p cmd is a given value of the power turbine speed issued by the vehicle control system. p cmd based on the power turbine speed sampling value N p Get the power turbine speed deviation △N p , the deviation △N p Input to the N p The controller obtains the gas turbine speed set value deviation △N g cmd, specifically, in the prior art, the gas turbine speed set value deviation △N is generally obtained by the following formula using the position PID increment calculation:g cmd, the formula is specifically expressed as:

[0084] ΔN g cmd=N p Kp×ΔN p (k)+N p Ki×∑ΔN p (k)+N p Kd×[ΔN p (k)-ΔN p (k-1)],

[0085] In the formula,

[0086] ΔN p (k) is the current cycle power turbine speed deviation, k is the current cycle, and k is an integer ≥ 0;

[0087] ∑ΔN p (k) is the accumulation of the power turbine speed deviation ΔNp, specifically, the power turbine speed deviation of each cycle accumulated and calculated since the vehicle enters the running state. Taking a helicopter as an example, when the helicopter leaves the air-slow state and starts to take off, the calculation of the power turbine speed deviation of each cycle begins;

[0088] N p Kp is the corresponding power turbine speed proportional coefficient,

[0089] N p Ki is the corresponding power turbine speed integral coefficient,

[0090] N p Kd is the corresponding differential coefficient of the power turbine speed,

[0091] Among them, N p Kp、N p Ki, N p Kd needs to be determined by adjusting the parameters according to the actual situation. Specifically, first adjust the power turbine speed proportional coefficient N p Kp. First, the power turbine speed integral coefficient N p Ki and the power turbine speed differential coefficient N p Kd is set to 0, and then the power turbine speed proportional coefficient N p The Kp value gradually increases from 0 until the system speed oscillates with a constant amplitude of about 0.5±% and stops increasing the power turbine speed proportional coefficient N. p Kp. On this basis, maintain the power turbine speed proportional coefficient N p The value of Kp remains unchanged, and the integral coefficient N of the power turbine speed is increased p Ki, the power turbine speed integral coefficient Np Ki gradually increases from 0, and the system speed and the target speed are gradually approaching. When the difference between the actual speed and the target speed is ±0.1%, the system control accuracy is met. p The function of Kd is based on the speed of deviation change, and plays a leading role in the system. In most cases, the power turbine speed differential coefficient N p Kd does not need to be adjusted, and the differential adjustment effect can be increased as needed. Generally, the power turbine speed proportional coefficient N p Kp, the power turbine speed integral coefficient N p Ki and the power turbine speed differential coefficient N p Kd value is between 0-1.

[0092] S22: Based on the power turbine load signal sampling value, the current period gas turbine speed feedforward value is obtained by interpolating the power turbine load characteristic curve.

[0093] S23: Calculate the current cycle load signal change rate, and determine whether the current cycle load signal change rate is greater than a preset threshold. If so, perform gain compensation on the current cycle gas turbine speed feedforward value.

[0094] S24: The gas turbine speed set value deviation and the current cycle gas turbine speed feedforward value are added to obtain the gas turbine speed set value.

[0095] In this embodiment, in order to p cmd can be quickly fed back to the gas turbine speed N g The control closed loop enables the turboshaft engine to respond to load and disturbance changes more quickly and accurately, and further obtains the current cycle gas turbine speed feedforward value N based on the power turbine load signal sampling value CLP. g clp, deviation from the given value of the gas turbine speed △N g cmd jointly calculates the adjustment of the gas turbine speed.

[0096] Further, firstly, based on the power turbine load signal sampling value CLP, the power turbine load characteristic curve is interpolated to obtain the current cycle gas turbine speed feedforward value N g clp, wherein the power turbine load characteristic curve is a known characteristic curve corresponding to the turboshaft engine, and is generally provided with the turboshaft engine when it leaves the factory.

[0097] The current cycle load signal change rate is further calculated. The current cycle load signal change rate reflects the load change of the vehicle, and is preferably calculated by the following formula, which is specifically expressed as:

[0098] Wherein, CLP(k) is the sampling value of the power turbine load signal, and t is the unit cycle time.

[0099] When the load signal change rate of the current cycle exceeds a preset threshold, preferably, the preset threshold is 0.2%, the gas turbine speed feedforward value N of the current cycle is g clp performs gain compensation, specifically, based on the current period load signal change rate, the gain coefficient is obtained by interpolating the gain curve, and then the product of the current period gas turbine speed feedforward value and the gain coefficient is used as the compensated current period gas turbine speed feedforward value, wherein the gain curve is a known parameter curve corresponding to the turboshaft engine, which is generally provided with the turboshaft engine when it leaves the factory.

[0100] Then the gas turbine speed set value deviation △N g cmd and the current cycle gas turbine speed feedforward value N g clp is added to obtain the gas turbine speed set value N g cmd, then N is completed p Control operations.

[0101] Next, if Figure 1 As shown, steps S3-S6 are performed N g Control operations.

[0102] In this embodiment, in order to achieve more accurate N g Operation and control, in N g The control loop is carried out in parallel N g The speed control operation obtains the first fuel increment, N g The acceleration control operation obtains the second fuel increment, wherein:

[0103] In S3, the first fuel increment is calculated based on the difference between the gas turbine speed set value and the gas turbine speed sampling value to complete the N g Speed ​​control operation, including:

[0104] Based on the gas turbine speed set value N g cmd and the gas turbine speed sampling value N g The gas turbine speed deviation ΔN is calculated by the difference of S g, and further based on the gas turbine speed deviation ΔN g The first fuel increment is obtained by using an incremental PID control calculation, and the incremental PID control calculation is expressed as the following formula:

[0105] ΔWf×Kp×[ΔD(k)-ΔD(k-1)]+Ki×ΔD(k)+Kd×[ΔD(k)-2ΔD(k-1)+ΔD(k-2)], where,

[0106] ΔWf is the first fuel increment / the second fuel increment,

[0107] Kp is the corresponding proportionality coefficient,

[0108] Ki is the corresponding integration coefficient,

[0109] Kd is the corresponding differential coefficient,

[0110] ΔD(k) is the difference between the given value of the gas turbine speed and the sampled value of the gas turbine speed in the current cycle / the difference between the given value of the gas turbine acceleration and the sampled value of the gas turbine acceleration in the current cycle, where k is the current cycle and k is an integer ≥0.

[0111] The gas turbine speed deviation ΔN g The first fuel increment is calculated by using incremental PID control, which is specifically expressed as the following formula:

[0112] ΔWf1=N g Kp×||ΔN g (k)-ΔN g (k-1)+N g Ki×ΔN g (k)+N g Kd×[ΔN g (k)-2ΔN g (k-1)+ΔN g (k-2)], where

[0113] ΔWf1 is the first fuel increment,

[0114] N g Kp is the proportionality coefficient corresponding to the gas turbine speed,

[0115] N g Ki is the integral coefficient corresponding to the gas turbine speed,

[0116] N g Kd is the differential coefficient corresponding to the gas turbine speed,

[0117] ΔN g(k) is the gas turbine speed deviation in the current cycle,

[0118] Among them, N g Kp、N g Ki, N g Kd needs to be determined by adjusting the parameters according to the actual situation. First, the proportional coefficient N corresponding to the speed of the gas turbine is adjusted. g Kp. First, the integral coefficient N corresponding to the gas turbine speed g Ki and the gas turbine speed corresponding to the speed N g Kd is set to 0, and then the gas turbine speed corresponding to N g The Kp value gradually increases from 0 until the system speed oscillates with a constant amplitude of about 0.5±% and stops increasing the proportional coefficient N corresponding to the gas turbine speed. g Kp. On this basis, the proportional coefficient N corresponding to the speed of the gas turbine is maintained g The value of Kp remains unchanged, and the integral coefficient N corresponding to the speed of the gas turbine is increased g Ki, the integral coefficient N corresponding to the gas turbine speed g Ki gradually increases from 0, and the system speed and the target speed are gradually approaching. When the difference between the actual speed and the target speed is ±0.1%, the system control accuracy is met. The differential coefficient N corresponding to the gas turbine speed g The function of Kd is based on the speed of the deviation change, and plays a leading role in the system. In most cases, the differential coefficient N corresponding to the speed of the gas turbine is g Kd does not need to be adjusted, and the differential adjustment effect can be increased as needed. Generally, the proportional coefficient N corresponding to the gas turbine speed is g Kp, the integral coefficient N corresponding to the gas turbine speed g Ki and the differential coefficient N corresponding to the gas turbine speed g Kd value is between 0-1.

[0119] Compared with the existing technology that uses position PID control to calculate N g The fuel increment corresponding to the speed control adopts incremental PID control, which is closer to the actual working condition of the gas turbine and has a smaller error in the calculated result.

[0120] The N g The acceleration control operation specifically includes:

[0121] In step S3, the gas turbine acceleration planning value is calculated based on the difference between the gas turbine speed set value and the gas turbine speed sampling value.

[0122] Specifically, based on the gas turbine speed given value N g cmd and the gas turbine speed sampling value N g The difference of S is used to interpolate the nonlinear planning table of the engine to obtain the gas turbine acceleration planning value. By introducing the calculation of the gas turbine acceleration planning value, the dynamic characteristics of the turboshaft engine gas turbine can be fully utilized while ensuring the structural safety of the turboshaft engine, so that a more accurate estimation calculation of the dynamic acceleration of the gas turbine can be made.

[0123] Step S3 also includes obtaining the gas turbine acceleration limit value through gas turbine acceleration limit calculation based on the gas turbine speed sampling value NgS.

[0124] Specifically, the acceleration limit value corresponding to the gas turbine speed sampling value NgS in the current period is obtained by interpolating the acceleration characteristic curve of the gas turbine, wherein the gas turbine acceleration characteristic curve is a known characteristic curve of the turboshaft engine and is generally provided with the turboshaft engine when it leaves the factory.

[0125] Step S3 also includes inputting a tracking differentiator based on the gas turbine speed sampling value NgS and outputting the gas turbine acceleration sampling value NgdotS, with the purpose of further denoising the gas turbine acceleration sampling value to calculate a more accurate gas turbine acceleration sampling value. Compared with the method of collecting and returning the gas turbine acceleration sampling value through sensors in the prior art, this processing method further reduces the delay, and the calculation result is more accurate, which helps to further speed up the processing speed and accuracy of the gas turbine acceleration control.

[0126] Execute step S4, that is, use the smaller value of the gas turbine acceleration planning value and the gas turbine acceleration limit value as the gas turbine acceleration given value Ngdotcmd, in order to take into account the structural safety of the turboshaft engine when selecting the gas turbine acceleration given value.

[0127] Step S5 is executed, that is, the second fuel increment is calculated by using the incremental PID control calculation based on the difference between the gas turbine acceleration given value Ngdotcmd and the gas turbine acceleration sampling value NgdotS, which is specifically expressed as the following formula:

[0128] ΔWf2=N g dotKp×[ΔN g dot(k)-ΔN g dot(k-1)]+N g dotKi×ΔN g dot(k)+N g dotKd×[ΔNg dot(k)-2ΔN g dot(k-1)+ΔN g dot(k-2)],

[0129] In the formula,

[0130] ΔWf2 is the second fuel increment,

[0131] N g dotKp is the proportionality coefficient corresponding to the gas turbine speed acceleration,

[0132] N g dotKi is the integral coefficient corresponding to the gas turbine speed acceleration,

[0133] N g dotKd is the differential coefficient corresponding to the gas turbine speed acceleration, where N g dotKp、N g dotKi、N g dotKd needs to adjust the parameters according to the actual situation.

[0134] Specifically, first adjust the proportional coefficient N corresponding to the gas turbine speed acceleration g dotKp, firstly calculate the integral coefficient N corresponding to the gas turbine speed acceleration g dotKi and the gas turbine speed acceleration corresponding to N g dotKd is set to 0, and then the gas turbine speed acceleration corresponding to N g The dotKp value gradually increases from 0 until the system speed oscillates with a constant amplitude of about 0.5±% and stops increasing the proportional coefficient N corresponding to the gas turbine speed acceleration. g On this basis, the proportional coefficient N corresponding to the gas turbine speed acceleration is maintained. g The value of dotKp remains unchanged, and the integral coefficient N corresponding to the gas turbine speed acceleration is increased g dotKi, the integral coefficient N corresponding to the gas turbine speed acceleration g dotKi gradually increases from 0, and the system speed and the target speed are gradually approaching. When the difference between the actual speed and the target speed is ±0.1%, the system control accuracy is met. The differential coefficient N corresponding to the gas turbine speed acceleration g The function of dotKd is to act according to the speed of deviation change, and plays a leading role in the system. In most cases, the differential coefficient N corresponding to the gas turbine speed acceleration is gdotKd does not need to be adjusted, and the differential adjustment effect can be increased as needed. Generally, the proportional coefficient N corresponding to the gas turbine speed acceleration is g dotKp, the integral coefficient N corresponding to the gas turbine speed acceleration g dotKi and the differential coefficient N corresponding to the gas turbine speed acceleration g dotKd value is between 0-1.

[0135] ΔN g dot(k) is the difference between the gas turbine acceleration set value and the gas turbine acceleration sampling value in the current period.

[0136] There is generally no N-based g The acceleration control calculation corresponds to the fuel increment processing. This embodiment is based on N g Acceleration control calculation corresponds to the fuel increment, which is a processing method that is more in line with the fuel turbine characteristics of a turboshaft engine. The incremental PID control is used to calculate the fuel increment, and the calculation result obtained has a smaller error.

[0137] Further, step S6 is performed, i.e., the first fuel increment ΔWf1 or the second fuel increment ΔWf2 is selected based on the current working condition of the engine, which specifically includes:

[0138] Determine whether the current working state of the engine is in an acceleration state, and if so, select the larger value of the first fuel increment ΔWf1 and the second fuel increment ΔWf2,

[0139] Otherwise, the smaller value of the first fuel increment ΔWf1 and the second fuel increment ΔWf2 is selected.

[0140] like Figure 1 As shown, the N g The sum of the fuel increment output by the control operation and the fuel flow Wflast output in the previous cycle is used as the fuel set value of the current cycle. g The control operation is completed.

[0141] In this embodiment, N p The control link introduces a gain compensation process, which enables the speed control command issued by the vehicle to be fed back to the engine faster than the prior art, and the gas turbine speed given value obtained based on the gain compensation process is more accurate; in N g Control link introduces N g Acceleration control, with N g Speed ​​control constitutes a parallel control loop, in which N g The acceleration control link introduces N g Acceleration planning value calculation, and N gThe acceleration limit value calculation results are compared and the smaller value is taken as the N g The processing method of the acceleration given value can ensure the safety of the engine and obtain more accurate calculation results; by introducing a tracking differentiator, based on the N g The speed sampling value output is N g The acceleration sampling value processing method not only effectively removes the N g The noise of the speed sampling value is smaller than that of the acceleration sensor sampling N in the prior art. g The acceleration processing method obtains the N g The acceleration sampling speed is faster and the result accuracy is higher; based on the actual working condition of the engine, the N g Speed ​​setpoint and the N g The first fuel increment and the N g The acceleration given value and the N g The second fuel increment is calculated by calculating the difference of the acceleration sampling values, so as to realize the accurate calculation and output of the fuel increment within the cycle, thereby realizing the accurate control of the turboshaft engine; at the same time, the calculation of the first fuel increment and the second fuel increment both adopts the incremental PID control calculation method, which is more in line with the N of the turboshaft engine than the position PID control calculation commonly used in the prior art. g The characteristics enable the engine to take into account both the steady-state and dynamic performance of the engine when the corresponding load and external disturbance changes, with faster dynamic response speed, stronger adaptability and more precise regulation.

[0142] Embodiment 2:

[0143] The second specific embodiment of the present invention discloses a turboshaft engine control system based on an incremental dual-speed closed loop. This embodiment includes all the technical features of embodiment 1.

[0144] like Figure 2 As shown, the control system includes a power turbine speed controller, a gas turbine speed acceleration and speed parallel controller, a metering valve, and a tracking differentiator, wherein:

[0145] The power turbine speed controller is used to obtain a gas turbine speed given value based on a speed control instruction, a power turbine speed sampling value, and a power turbine load sampling value, and output it to the gas turbine speed acceleration and speed parallel controller;

[0146] The tracking differentiator outputs a gas turbine acceleration sampling value based on the gas turbine speed sampling value;

[0147] The gas turbine speed acceleration and speed parallel controller is used to output the current cycle given fuel flow to the metering valve based on the gas turbine speed given value, the gas turbine acceleration sampling value, and the gas turbine speed sampling value;

[0148] The metering valve is used to adjust the opening of the metering valve based on the difference between the current cycle given fuel flow and the real-time sampling value of the output fuel flow until the output fuel flow is equal to the current cycle given fuel flow.

[0149] Specifically, compared with the prior art, the turboshaft engine control system disclosed in this embodiment adds a gain compensation module to the power turbine speed controller. The gain compensation module obtains the gas turbine speed feedforward value based on the power turbine load sampling value by interpolating the vehicle load characteristic curve, and further calculates the current period load signal change rate to determine whether it is necessary to perform gain compensation on the gas turbine speed feedforward value. The specific method can be seen in the corresponding description in Example 1.

[0150] Compared with the prior art, the turboshaft engine control system disclosed in this embodiment also includes the gas turbine speed acceleration and speed parallel controller, the tracking differentiator, wherein the tracking differentiator outputs the gas turbine acceleration sampling value based on the gas turbine speed sampling value, which is faster and more accurate than the prior art in which an acceleration sensor is used to sample the gas turbine speed acceleration.

[0151] Furthermore, the gas turbine speed acceleration and speed parallel controller includes a gas turbine speed controller, a gas turbine speed acceleration controller, and an integrated voter, wherein:

[0152] The gas turbine speed controller generates a first fuel increment based on the difference between the gas turbine speed set value and the gas turbine speed sampling value and outputs the first fuel increment to the integrated voter.

[0153] The gas turbine speed acceleration controller generates a second fuel increment based on the difference between the gas turbine speed set value and the gas turbine speed sampling value and the gas turbine speed sampling value, and outputs the second fuel increment to the integrated voter.

[0154] The integrated voter determines to select the first fuel increment or the second fuel increment based on the engine operating conditions and obtains the given fuel amount of the current cycle based on the selected fuel increment.

[0155] The turboshaft engine control system disclosed in this embodiment does not basically change the hardware structure of the existing turboshaft engine control system. It only enters the corresponding control and operation modules in the control system. By implementing the control method of Example 1, more precise and rapid control of the turboshaft engine is achieved. Compared with the existing turboshaft engine control system, it has stronger adaptability and robustness, and can significantly improve the response speed and ability of the turboshaft engine to cope with load and disturbance changes.

[0156] Embodiment 3:

[0157] The third specific embodiment of the present invention discloses a turboshaft engine based on incremental dual-speed closed-loop control, wherein the turboshaft engine includes an engine body, and a turboshaft engine control system based on incremental dual-speed closed-loop disclosed in Embodiment 2, and this embodiment includes all the technical features of Embodiments 1 and 2, wherein the control system obtains the current cycle fuel flow based on the gas turbine speed sampling value, the power turbine speed sampling value, the load signal sampling value, and the real-time sampling value of the output fuel flow, and outputs fuel to the engine body according to the current cycle fuel flow.

[0158] The turboshaft engine disclosed in this embodiment has a faster response speed and adaptability when dealing with large loads and complex disturbances than existing turboshaft engines, and can take into account both steady-state and dynamic performance.

[0159] Embodiment 4:

[0160] The fourth specific embodiment of the present invention discloses a vehicle, which includes an operation control system and the turboshaft engine described in Example 3. This embodiment includes all the technical features of Example 1, Example 2, and Example 3; the operation control system issues a speed control instruction to the turboshaft engine, and the turboshaft engine generates corresponding power and operates based on the speed control instruction.

[0161] The vehicle disclosed in this embodiment has obvious advantages in adjustment capability, safety, and stability when dealing with large loads and complex disturbances compared to existing vehicles of the same type.

[0162] Exemplarily, the vehicle may be an aircraft using the turboshaft engine disclosed in Implementation 3, such as a helicopter, a drone, etc., or a water vehicle such as a ship, or an underwater vehicle such as a submarine, or a land vehicle such as a hovercraft, a turboshaft engine-powered car, etc.

[0163] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0164] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A turboshaft engine control method based on an incremental dual-speed closed loop, characterized in that: The method specifically comprises: The gas turbine output speed, the power turbine output speed, and the power turbine load signal are sampled respectively to obtain a gas turbine speed sampling value, a power turbine speed sampling value, and a power turbine load signal sampling value; A gas turbine speed set value is obtained based on a difference between a speed control instruction and the power turbine speed sampling value and a power turbine load signal sampling value; Based on the difference between the gas turbine speed set value and the gas turbine speed sampling value, a gas turbine acceleration planning value and a first fuel increment are calculated respectively, and based on the gas turbine speed sampling value, a gas turbine acceleration limit value and a gas turbine acceleration sampling value are calculated; Calculating a gas turbine acceleration given value based on a smaller value of the gas turbine acceleration planning value and the gas turbine acceleration limit value; Calculating a second fuel increment based on a difference between the gas turbine acceleration set value and the gas turbine acceleration sampling value; The first fuel increment or the second fuel increment is selected based on the current operating condition of the engine, and is added to the fuel flow of the previous cycle to obtain the given fuel flow of the current cycle.

2. A turboshaft engine control method based on an incremental dual-speed closed loop according to claim 1, characterized in that: The difference between the speed control instruction and the power turbine speed sampling value and the power turbine load signal sampling value is used to obtain the gas turbine speed set value by the following method, and the method specifically includes: The gas turbine speed set value deviation is calculated based on the difference between the speed control instruction and the power turbine speed sampling value; Based on the power turbine load signal sampling value, a current period gas turbine speed feedforward value is obtained by interpolating the power turbine load characteristic curve; Calculating the load signal change rate of the current cycle, determining whether the load signal change rate of the current cycle is greater than a preset threshold, and if so, performing gain compensation on the gas turbine speed feedforward value of the current cycle; The gas turbine speed set value is obtained by adding the gas turbine speed set value deviation and the current period gas turbine speed feedforward value.

3. A turboshaft engine control method based on an incremental dual-speed closed loop according to claim 2, characterized in that: The gain compensation for the current cycle gas turbine speed feedforward value specifically refers to obtaining a gain coefficient by interpolating the gain curve based on the current cycle load signal change rate, and then using the product of the current cycle gas turbine speed feedforward value and the gain coefficient as the compensated current cycle gas turbine speed feedforward value.

4. A turboshaft engine control method based on an incremental dual-speed closed loop according to claim 1, characterized in that: The gas turbine acceleration planning value is calculated based on the difference between the gas turbine speed given value and the gas turbine speed sampling value, specifically refers to looking up the engine nonlinear planning table based on the difference between the gas turbine speed given value and the gas turbine speed sampling value and performing interpolation calculation to obtain the gas turbine acceleration planning value.

5. A turboshaft engine control method based on an incremental dual-speed closed loop according to claim 1 or 2, characterized in that: The first fuel increment is calculated based on the difference between the gas turbine speed set value and the gas turbine speed sampling value, and the second fuel increment is calculated based on the difference between the gas turbine acceleration set value and the gas turbine acceleration sampling value. Both use an incremental PID control calculation method, which is specifically expressed as the following formula: ΔWf=Kp×[ΔD(k)-ΔD(k-1)]+Ki×ΔD(k)+Kd×[ΔD(k)-2ΔD(k-1)+ΔD(k-2)], In the formula, ΔWf is the first fuel increment / the second fuel increment, Kp is the corresponding proportionality coefficient, Ki is the corresponding integration coefficient, KD is the corresponding differential coefficient, ΔD(k) is the difference between the gas turbine speed set value and the gas turbine speed sampling value in the current cycle / the difference between the gas turbine acceleration set value and the gas turbine acceleration sampling value in the current cycle, where k is the current cycle.

6. A turboshaft engine control method based on an incremental dual-speed closed loop according to claim 1, characterized in that: The selecting the first fuel increment or the second fuel increment based on the current operating condition of the engine specifically includes: determining whether the current working state of the engine is in an acceleration state, and if so, selecting the larger value of the first fuel increment and the second fuel increment, Otherwise, the smaller value between the first fuel increment and the second fuel increment is selected.

7. A turboshaft engine control system based on an incremental dual-speed closed loop, characterized in that: The control system includes a power turbine speed controller, a gas turbine speed acceleration and speed parallel controller, a metering valve, and a tracking differentiator, wherein: The power turbine speed controller is used to obtain a gas turbine speed given value based on a speed control instruction, a power turbine speed sampling value, and a power turbine load sampling value, and output it to the gas turbine speed acceleration and speed parallel controller; The tracking differentiator outputs a gas turbine acceleration sampling value based on the gas turbine speed sampling value; The gas turbine speed acceleration and speed parallel controller is used to output the current cycle given fuel flow to the metering valve based on the gas turbine speed given value, the gas turbine acceleration sampling value, and the gas turbine speed sampling value; The metering valve is used to adjust the opening of the metering valve based on the difference between the current cycle given fuel flow and the real-time sampling value of the output fuel flow until the output fuel flow is equal to the current cycle given fuel flow.

8. The control system according to claim 7, characterized in that: The gas turbine speed acceleration and speed parallel controller includes a gas turbine speed controller, a gas turbine speed acceleration controller, and a comprehensive voter, wherein: The gas turbine speed controller generates a first fuel increment based on the difference between the gas turbine speed set value and the gas turbine speed sampling value and outputs the first fuel increment to the integrated voter. The gas turbine speed acceleration controller generates a second fuel increment based on the difference between the gas turbine speed set value and the gas turbine speed sampling value and the gas turbine speed sampling value, and outputs the second fuel increment to the integrated voter. The integrated voter determines to select the first fuel increment or the second fuel increment based on the engine operating conditions and obtains the given fuel amount of the current cycle based on the selected fuel increment.

9. A turboshaft engine based on incremental dual-speed closed-loop control, characterized in that: The turboshaft engine includes the control system and engine body as described in claim 8, wherein the control system obtains the current cycle fuel flow based on the gas turbine speed sampling value, the power turbine speed sampling value, the load signal sampling value, and the real-time sampling value of the output fuel flow, and outputs fuel to the engine body according to the current cycle fuel flow.

10. A means of transport, characterized in that: The vehicle comprises an operation control system, the turboshaft engine of claim 9; The operation control system issues a speed control instruction to the turboshaft engine, and the turboshaft engine generates corresponding power and operates based on the speed control instruction.

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