Control method and control device for hybrid turbine engine

Abstract

The invention relates to a control method for controlling a hybrid turbine engine (1), comprising the steps of: determining a series of deviations, each deviation being a difference between a measured value of a series of measured values (5) of a driveshaft speed of the hybrid turbine engine (1) and a setpoint of a series of engine speed setpoints (7); determining a change in the fuel flow rate and a change in the electrical torque, determining a difference between a last measurement and a penultimate measurement in each use of a series of measurements, a last deviation associated with the last measurement, and a sum of deviations of a series of deviations; and controlling the hybrid turbine engine (1) to vary the fuel flow and the electric torque.

Description

Technical Field

[0001] The present invention relates to the control of a hybrid turbine engine, ie a turbine engine having both a thermal drive and an electric drive.

[0002] The invention relates in particular to a control method and a multivariable control device, ie taking into account a plurality of degrees of freedom of the controlled system. Background Art

[0003] A hybrid turbine engine has two degrees of freedom: the fuel flow rate sent to the combustion chamber and the electrical torque applied to the turbine engine's drive shaft. Therefore, a hybrid turbine engine is considered a multivariable system.

[0004] The fuel flow rate sent to the combustion chamber and the electrical torque applied to the turbine engine's drive shaft are the turbine engine's system "inputs." Each input contributes to the engine speed, i.e., the angular velocity of the drive shaft, which is the turbine engine's system "output."

[0005] Two inputs to the system must be regulated, namely the fuel flow sent to the combustion chamber and the electrical torque applied to the drive shaft of the turbine engine: the values ​​of the inputs must be determined automatically and in real time to ensure good operation of the turbine engine, ie to obtain a satisfactory output.

[0006] Good operation of the turbine engine can be characterized in particular by good tracking of the setpoint curve by the output of the turbine engine.

[0007] A setpoint curve for an output variable (e.g., the output variable of engine speed) is a continuous curve or a time series of setpoint values ​​that represents the desired evolution of this output variable (i.e., in this case, the speed of the drive shaft) over time. The closer the actual engine speed is to this setpoint curve, the better the turbine engine is performing.

[0008] The method for controlling a turbine engine is to adjust an input quantity of a system of the turbine engine based on at least one output quantity of the system of the turbine engine. To do this, not only a set point curve of the output quantity must be available, but also a real-time measurement value of the output quantity must be available.

[0009] The aforementioned method for controlling a hybrid turbine engine is unsatisfactory because it may require an additional output quantity, such as the fuel load enrichment ratio. This presupposes not only a setpoint curve but also a real-time measurement of this additional quantity. However, both of these items, especially the enrichment ratio, can be difficult to determine or implement.

[0010] The method for controlling a hybrid turbine engine, as described above, is also unsatisfactory because it can adjust one input variable based on another. For example, the electric torque can be determined after and as a function of the fuel flow rate. In particular, the electric torque can remain zero as long as the fuel flow rate can increase. Consequently, the turbine engine's two degrees of freedom are not used independently and optimally.

[0011] Therefore, there is a need for a method for controlling a hybrid turbine engine that enables independent use of two degrees of freedom without requiring the use of outputs that are difficult to determine or implement setpoint curves or real-time measurements. Summary of the Invention

[0012] An object of the present invention is to provide a method for controlling a hybrid turbine engine which enables the independent use of two degrees of freedom without the use of outputs which are difficult to determine or implement setpoint curves or real-time measurements.

[0013] Within the scope of the present invention, this object is achieved by a method for controlling a hybrid turbine engine, comprising the following steps:

[0014] - Determine a series of deviations, each deviation being the difference between a measured value and a set point as follows:

[0015] o the one measurement is one of a series of measurements of the rotational speed of a drive shaft of the hybrid turbine engine,

[0016] o the one set point is one set point in a series of engine speed set points,

[0017] - determining a change in the fuel flow rate and determining a change in the electric torque, the determining steps being in particular performed simultaneously and each of the determining steps using:

[0018] o the difference between the last measurement in a series of measurements and the second to last measurement in a series of measurements, the last deviation associated with the last measurement, and

[0019] o the sum of the deviations of a series of deviations; and

[0020] The hybrid turbine engine is controlled to change the fuel flow rate by the determined change in the fuel flow rate and to change the electric torque by the determined change in the electric torque.

[0021] This method is advantageously and optionally accomplished by the following different features, taken alone or in combination:

[0022] - during the determination of the change in the fuel flow and the determination of the change in the electric torque, determining the product of the gain matrix and a vector formed by the difference between the last measured value and the second to last measured value, the last deviation, and the sum of the deviations;

[0023] - obtaining a gain matrix by interpolating between two reference matrices from a set of reference matrices to take into account the operating point of the hybrid turbine engine associated with the last measured value;

[0024] The present invention is also applicable to a control device for a hybrid turbine engine, comprising:

[0025] an input configured to receive a series of measured values ​​of the engine speed of the hybrid turbine engine,

[0026] a memory configured to record a series of measured values ​​and a series of rotational speed set points,

[0027] -Calculator, the calculator is configured to:

[0028] o Determine a series of deviations, each deviation being the difference between a measured value and a set point as follows:

[0029] - the one measurement value is one measurement value from a series of measurements of the engine speed of the hybrid turbine engine,

[0030] - the one set point is one set point in a series of engine speed set points,

[0031] o determining a change in fuel flow and a change in electric torque, in particular simultaneously determining a change in fuel flow and a change in electric torque, each of the determining steps using:

[0032] - the difference between the last measurement in a series of measurements and the second to last measurement in a series of measurements,

[0033] - the last deviation associated with the last measured value, and

[0034] - the sum of the deviations of a series of deviations; and

[0035] An output terminal is configured to provide instructions to the hybrid turbine engine.

[0036] The invention also relates to a turbine engine comprising a control device as described above and to an aircraft comprising a turbine engine of this type. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Other characteristics and advantages of the present invention will become further apparent from the following description, which is purely illustrative and non-limiting and must be read with reference to the accompanying drawings, in which:

[0038] Figure 1 is a schematic diagram of a control device according to one embodiment of the present invention;

[0039] Figure 2 is a schematic diagram of acceleration tracking control according to an embodiment of the present invention; and

[0040] Figure 3 FIG. 1 is a schematic diagram of deceleration tracking control according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] Hybrid turbo engine

[0042] Figure 1 is a schematic diagram of a control device according to an embodiment of the present invention, in which a hybrid turbine engine 1 includes two drives for a high-pressure drive shaft and / or a low-pressure drive shaft, the high-pressure drive shaft and / or the low-pressure drive shaft being started by thermal drive and electric drive.

[0043] From a control perspective, a hybrid turbine engine can be considered as a multivariable system consisting of two controlled or input variables:

[0044] -exist Figure 1 The fuel flow command "WF" with reference numeral 9 is sent to the local circuit of the fuel gauge of the hybrid turbine engine 1,

[0045] -exist Figure 1 The electric torque command “TRQ” with reference numeral 11 is applied by the electric motor to the high-voltage drive shaft and / or the low-voltage drive shaft.

[0046] More generally, the hybrid turbine engine 1 has a number of output quantities that must be regulated and / or limited, such as in particular the rotational speed of the low-pressure drive shaft, the rotational speed of the high-pressure drive shaft, and optionally the combustion chamber inlet pressure.

[0047] Furthermore, the turbine engine must be a dual-shaft, dual-flow type, comprising a low-pressure shaft and a high-pressure shaft. In this case, the controlled electric torque described above is the electric torque applied to the high-pressure shaft. Electric torque can also be applied to the low-pressure shaft, but within the scope of this disclosure, this torque is indirectly controlled based on the control of the electric torque applied to the high-pressure shaft.

[0048] Control device

[0049] Figure 12 , a control device 3 capable of controlling the hybrid turbine engine 1 is shown.

[0050] The operation of the hybrid turbine engine 1 is regulated by using a plurality of input quantities and an output quantity, Figure 1 The input quantities shown in FIG arrive at the hybrid turbine engine 1 on the “input” side, Figure 1 The output quantities shown in φ leave the hybrid turbine engine 1 on the “output” side.

[0051] The input quantities used are fuel flow and electric torque. More precisely, the control device 3 provides a fuel flow command 9 to be sent to the combustion chamber and an electric torque command 11 to be applied to the drive shaft of the hybrid turbine engine 1. The output quantity is the engine speed. This can be the speed of the high-pressure drive shaft or the low-pressure drive shaft. A measured value 5 of the engine speed is sent to the control device 3. The measured value 5 of the engine speed assumes that a sensor for the engine speed is available in the hybrid turbine engine 1.

[0052] The control device 3 may also receive an engine speed setpoint 7 .

[0053] A setpoint is a continuous curve or a time-domain sequence of values ​​representing the evolution of the engine speed (ie the angular velocity of the drive shaft) over time. In particular, a setpoint can be associated with a specific maneuver such as take-off, landing, etc.

[0054] The control device 3 can also receive a measured value of the external pressure 6 .

[0055] Based on the received measured values ​​5 of the engine speed and the measured values ​​6 of the external pressure, the control device 3 can form indicators, such as: a transient detection indicator, which uses a signal to indicate the operating speed when the engine parameters change significantly (take-off, maneuvering, cavitation crossing, landing, etc.); a fuel flow limitation indicator or a fuel saturation indicator, which indicates that the fuel flow cannot be increased anymore; or an electric torque limitation indicator or an electric saturation indicator, which indicates that the electric torque cannot be increased anymore.

[0056] The control device 3 can also be a closed loop. To this end, the control device 3 can receive the following instructions as input,

[0057] - a fuel flow command 9 along the fuel return line 17, and / or

[0058] - an electrical torque command along the electrical torque return line 15 .

[0059] This means that the control device 3 has an incremental operation in which the fuel flow rate command 9 and the electric torque command 11 determined in step k use the fuel flow rate command 9 and the electric torque command 11 determined in step k-1 temporally preceding step k.

[0060] The fuel flow command 9 indicated by the fuel return line 17 and the electric torque command 11 indicated by the electric torque return line 15 (i.e. the fuel flow command and electric torque command determined in step k-1) are fed back to the control device 3 so that any deviation between the initial command and the saturation state can be taken into account.

[0061] The control device 3 may include, for example, a memory 31 configured to record:

[0062] a series of set points 7 of the engine speed, in particular the evolution over time of the angular speed of the drive shaft of the hybrid turbine engine 1 , and / or

[0063] a series of measured values ​​5 of the engine speed, in particular the received evolution of the speed of the hybrid turbine engine 1 over time,

[0064] Furthermore, the memory 31 can also record the indicator 13 and / or a result previously determined in the control device 3 (for example in the previous step k- 1 ).

[0065] The term "series of set points" or "series of measured values" is understood to mean a temporal series of consecutive values ​​of set points or measured values. Each value is time-stamped and / or associated with a point in time, so that the series of set points or the series of measured values ​​corresponds to the evolution of a quantity over time that can be graphically displayed.

[0066] The control device 3 may further comprise a computer 33 configured to determine (in particular in real time) the fuel flow command 9 and the electric torque command 11, for example based on received data (such as a measurement 5 of the engine speed, a measurement 6 of the external pressure and / or an engine speed set point 7) and / or recorded data (such as a series of set points 7 of the engine speed, a series of measurement 5 of the engine speed and / or an indicator 13).

[0067] Figure 1 The control device 3 shown may correspond to a multiple-input single-output (MISO) type architecture, since it supplies two inputs to the hybrid turbine engine 1 from a single output of the hybrid turbine engine 1 .

[0068] Control methods

[0069] The control device 3 shown enables the implementation of a control method for the hybrid turbine engine 1 , which control method comprises the following steps.

[0070] In a first step, a series of engine speed setpoints 7 is recorded, in particular the angular speed of the drive shaft of the hybrid turbine engine 1. The recording of the first step is performed, for example, in the memory 31 of the control device 3. The recording of the series of engine speed setpoints 7 can be performed before the hybrid turbine engine 1 is started and / or before any measured values ​​5 of the engine speed are obtained on the hybrid turbine engine 1.

[0071] A series of engine speed set points 7 can be set at the value NHC p where p is an index ranging from 0 to N and represents the position of the value in the series.

[0072] In a second step, a series of measurements 5 of the engine speed are recorded.

[0073] Once the hybrid turbine engine 1 is started, the engine speed is monitored and successive measured values ​​are transmitted to the control device 3, thereby forming a series of engine speed measurement values ​​5 comprising an increasing number of measurement values ​​over time. This second step of recording is performed, for example, in the memory 31 of the control device 3.

[0074] A series of measurements of engine speed 5 can be expressed as NH p where p is an index ranging from 0 to k and represents the position of the value in the series. Index k is the last measurement value NH received. k The index of .

[0075] These indices correspond to time steps or successive operating points of the hybrid turbine engine 1 .

[0076] In a third step, computer 33 determines a series of deviations between measured value 5 of engine speed and engine speed setpoint 7, each deviation being equal to the difference between measured value 5 of engine speed and engine speed setpoint 7, the engine speed setpoint 7 being associated with measured value 5 of engine speed. The series of measured values ​​5 of engine speed and the series of engine speed setpoints 7 do not necessarily contain the same number of values, but they are referenced to each other in the time domain. In other words, each measured value 5 of engine speed is associated with an engine speed setpoint 7, and the measured values ​​5 of engine speed and the setpoints coincide in time. The goal of the regulation is to bring each measured value 5 of engine speed as close as possible to its corresponding engine speed setpoint 7.

[0077] A range of deviations can be expressed as ENH p Written in the form of , where p is an index ranging from 0 to k, the deviation is calculated index by index according to the following calculation:

[0078] ENHp =NH p -NHC p .

[0079] In a fourth step, the computer 33 determines (in particular simultaneously determines) the change in the fuel flow rate ΔWF p and the change of electric torque ΔTRQ p , the change in fuel flow rate corresponds to the difference in fuel flow rate instruction 9 between the moment p and the previous moment p-1, that is:

[0080] ΔWF p =WF p -WF p-1 ,

[0081] The change in electric torque corresponds to the difference in electric torque command 11 between the moment p and the previous moment p-1, that is:

[0082] ΔTRQ p =TRQ p -TRQ p-1 .

[0083] The fuel flow rate command 9 and the electric torque command 11 are time-transformed signals and can be expressed as a time domain sequence WF of the fuel flow rate command. p And the sequence of electric torque command TRQ p discretized form.

[0084] The value of the time domain sequence of the fuel flow command WF p and the value of the sequence of electric torque commands TRQ p Indicated by an index p varying from 0 to k, each instruction is associated with the same measurement value.

[0085] Change in fuel flow command ΔWF p and the change of the electric torque command ΔTRQ p is determined as a function of:

[0086] the difference in engine speed between the last measured value 5 and the second to last measured value 5 of the engine speed of the hybrid turbine engine 1 ,

[0087] - Deviation ENH associated with the last measured value 5 of the engine speed k ,as well as

[0088] -The sum of all deviations.

[0089] The last measured value 5 of the engine speed is the last measured value received by the control device 3 and therefore constitutes the most recent measured value of the state of the engine speed. This is therefore the measured value NH corresponding to the last index k. kThe difference between the last measured value 5 and the second to last measured value 5 of the engine speed is written as:

[0090] ΔNH k =NH k --NH k-1 .

[0091] The deviation associated with the last measured value 5 of the engine speed is written as:

[0092] ENH k =NH k -NHC k .

[0093] The sum of all deviations, IENH, is calculated using the following expression: k :

[0094] IENH k =ENH0+ENH1+ENH2+...+ENH k-1 +ENH k .

[0095] The sum of all deviations IENH k Corresponds to the integral of the error from index p=0 to the last index p=k.

[0096] The method described above uses three output quantities, all of which are based on angular velocity (angular velocity setpoints and angular velocity measurements): the difference between the last and penultimate measured values, the deviation associated with the last measured value, and the sum of all deviations. These three quantities enable the determination of input quantities without using output quantities other than angular velocity, particularly those that would make it difficult to determine or implement setpoint curves or real-time measurements. Furthermore, by simultaneously determining the values ​​of the input quantities, the two degrees of freedom of the turbine engine can be used in a more optimized manner than in the prior art.

[0097] This type of determination relies on a specific modeling of the hybrid turbine engine 1 by a system of the linear time-invariant (LTI) type, where the engine speed when advancing from index k to index k+1 is given by a first equation or equation (1):

[0098]

[0099] Equation (1) is a comprehensive model. Equation (1) constitutes a mathematical description of the system, making it possible to relate the inputs (i.e., fuel flow command 9, fuel flow setpoint, electric torque command 11 and / or electric torque setpoint) and the output (i.e., engine speed).

[0100] The term A of equation (1) is the state matrix. The term A of equation (1) can be assimilated to a time constant, specifically representing the response time associated with the moment of inertia of the hybrid turbine engine 1 .

[0101] Term B of equation (1) is the control matrix. Term B of equation (1) can contain information about the system gains (particularly the static gains) that establish the relationship between the set point increment (fuel flow and / or electric torque) and the speed increment by which the speed increment is achieved once the speed has stabilized.

[0102] In order to eliminate the dynamic error (also called hysteresis, consisting of the delay between a linear change in the setpoint and a corresponding change in the engine speed), provision is made for the use of an “enhanced” synthetic model.

[0103] For this purpose, in addition to using the difference ΔNH between the last measured value 5 and the second to last measured value 5 of the engine speed k , the "enhanced" synthesis model also uses:

[0104] - Deviation ENH associated with the last measured value 5 of the engine speed k , which deviation corresponds in particular to the servo error, and

[0105] -The sum of all deviations IENH k , the sum of all deviations corresponds in particular to the integral of the servo error,

[0106] According to a second equation or equation (2) which is more general than the first equation or equation (1):

[0107]

[0108] ΔNHC k =NHC k -NHC k-1 Corresponds to the difference between the last set point of rank k and the second to last set point of rank k-1.

[0109] Equation (2) can be used to determine a third equation or equation (3) that converts the change in fuel flow rate ΔWF into the form of a third equation or equation (3). k and the change of electric torque ΔTRQ k Expressed as a function of:

[0110] - the difference ΔNH between the last measured value 5 and the second to last measured value 5 of the engine speed k , - deviation ENH associated with the last measured value 5 of the engine speed k ,as well as

[0111] -The sum of all deviations IENH k .

[0112] The third equation or equation (3) is:

[0113]

[0114] where the term "K" is the gain matrix.

[0115] The change in fuel flow rate ΔWF is obtained (particularly simultaneously obtained) by multiplying the gain matrix K and the vector formed by k and the change of electric torque ΔTRQ k :

[0116] - the difference ΔNH between the last measured value 5 and the second to last measured value 5 of the engine speed k , - deviation ENH associated with the last measured value 5 of the engine speed k ,as well as

[0117] -The sum of all deviations IENH k .

[0118] In order to use the corrector, the gain matrix K must be determined in advance, which is equivalent to performing a "synthesis of a multivariate corrector".

[0119] This synthesis is of the “Linear Quadratic State Feedback” type (Linear Quadratic LQ Command) and consists in minimizing a criterion or quantity “J” whereby the weighting matrices Q, R and S are present.

[0120] These are set at the start of the calculation according to the desired engine behavior, in particular according to the desired absence of hysteresis.

[0121] More precisely, the choice of weighting matrices Q, R and S enables different adjustments of the corrector and the desired engine behavior to be obtained, such as eliminating hysteresis, i.e. minimizing the transfer between setpoint and servo error in the 2-norm sense by constraining the error dynamics.

[0122]

[0123] Minimizing the criterion J via the Lagrangian enables the use of an analytical expression for the gain matrix of the form:

[0124] K=(R+B T PB)- 1 (B T PA+S)

[0125] Here, the terms R, B, A, and S are known matrices. The only remaining matrix P remains to be determined from the unique solution of the discrete algebraic Riccati equation, which is:

[0126]

[0127] in:

[0128] and

[0129] This last equation enables the matrix P and therefore the gain matrix K to be determined.

[0130] During the control method, knowing the gain matrix K enables the determination (in particular simultaneous determination) of the change in the fuel flow rate ΔWF using a third formula or equation (3) k and the change of electric torque ΔTRQ k , the change in fuel flow and the change in electric torque are given as the difference ΔNH between the last measured value 5 and the second to last measured value 5 of the engine speed k , the deviation ENH associated with the last measured value 5 of the engine speed k , and the sum of all deviations IENH k Function:

[0131]

[0132] Note that the gain matrix K depends on the operating point of the engine. More precisely, the gain matrix K is determined based on the terms A and B that depend on the operating point of the engine.

[0133] This is taken into account in practice by predetermining a set of reference matrices and calculating the gain matrix by interpolation between two reference matrices based on the measured values ​​of the engine operating point.

[0134] This set of reference matrices is predetermined before the control method is implemented. Each reference matrix is ​​associated with an operating point of the hybrid turbine engine 1 (the so-called reference point).

[0135] The reference matrix is ​​associated with an equation for the evolution of a tracking vector of a rotational speed command or a tracking vector of an angular velocity, which is formed by a rotational speed change or angular velocity change at a certain moment, a difference from the rotational speed or angular velocity commanded at that moment, and an integral based on the difference.

[0136] The operating point can be derived in particular from internal engine measurements (e.g., measured values ​​of the rotational speed or angular velocity of the drive shaft, or measured values ​​of the inlet pressure of the combustion chamber) and external engine measurements (e.g., external pressure). Thus, the operating point can be associated with a vector of multiple measured values.

[0137] The measured operating point (more specifically the “operating point” vector) enables the gain matrix K to be used at this point to be determined by linear interpolation between reference matrices associated with reference vectors surrounding the “operating point” vector.

[0138] This can be managed through “augmentation” of the model to account for fuel saturation (i.e., not increasing the fuel set point beyond a certain maximum (also known as “saturation control”)) and / or torque (i.e., not increasing the set point of electric torque due to machine limitations or limitations on hybrid power levels).

[0139] For example, the state vector includes:

[0140] - the difference ΔNH between the last measured value 5 and the second to last measured value 5 of the engine speed k ,

[0141] - Deviation ENH associated with the last measured value 5 of the engine speed k , which deviation corresponds in particular to the servo error, and

[0142] -The sum of all deviations IENH k , the sum of all deviations corresponds in particular to the integral of the servo error,

[0143] These state vectors can be completed by controlling the deviation between saturation and command calculated by the trajectory tracking corrector.

[0144] Different ways of considering this type of state vector can be considered, in particular by considering the state vector as a disturbance and / or using the mathematical tools described previously in one way.

[0145] The fuel flow setpoint 9 and the torque setpoint 11 are calculated by numerical integration according to the following equations:

[0146]

[0147] result

[0148] Figure 2 and Figure 3 1 and 2 are schematic diagrams of instruction tracking during acceleration and deceleration according to the present invention, respectively, and show numerical simulation results of instruction tracking according to the control method described above.

[0149] Figure 2 More specifically, it relates to the acceleration of engine speed.

[0150] Figure 2 Including the first curve Figure 2A, in the first graph, the ordinate axis corresponds to the engine speed or angular velocity, and the abscissa axis corresponds to time.

[0151] Figure 2 The first curve Figure 2 A includes:

[0152] a setpoint curve 20 corresponding to the engine speed setpoint 7,

[0153] a rotational speed curve 22 corresponding to the measured value 5 of the engine speed, and

[0154] A minimum speed curve 24 , which corresponds to the minimum engine speed.

[0155] also, Figure 2 Including the second curve Figure 2 B. In the second graph, the ordinate axis corresponds to the fuel flow rate, and the abscissa axis corresponds to time.

[0156] Figure 2 The second curve Figure 2 B includes:

[0157] a maximum fuel flow curve 30 corresponding to the maximum fuel flow which cannot be exceeded for the current engine speed,

[0158] a minimum fuel flow curve 34 corresponding to a minimum fuel flow, below which the fuel flow does not drop, and

[0159] A fuel command curve 32 , which corresponds to the fuel flow rate command 9 .

[0160] also, Figure 2 Including the third curve Figure 2 C. In the third graph, the ordinate axis corresponds to the electric torque, and the abscissa axis corresponds to time.

[0161] Figure 2 The third curve Figure 2 C includes:

[0162] An electric torque command curve 40 , which corresponds to the electric torque command 11 .

[0163] Figure 2 The first curve Figure 2 A. Second Curve Figure 2 B and the third curve Figure 2 C are synchronized so that, at each moment, a different graph gives a setpoint, a measured value and / or a command value corresponding to the operating point of the hybrid turbine engine 1 .

[0164] at last, Figure 3 More specifically, it relates to the reduction of engine speed.

[0165] Figure 3 Including the first curve Figure 3 A, in the first graph, the ordinate axis corresponds to angular velocity, and the abscissa axis corresponds to time.

[0166] Figure 3 The first curve Figure 3 A includes:

[0167] a setpoint curve 50 corresponding to the engine speed setpoint 7, and

[0168] A rotational speed curve 52 , which corresponds to the measured value 5 of the engine speed.

[0169] also, Figure 3 Including the second curve Figure 3 B. In the second graph, the ordinate axis corresponds to the fuel flow rate, and the abscissa axis corresponds to time.

[0170] Figure 3 The second curve Figure 3 B includes:

[0171] a maximum fuel flow curve 60 corresponding to the maximum fuel flow that cannot be exceeded for the current engine speed,

[0172] a minimum fuel flow curve 64 corresponding to a minimum fuel flow, below which the fuel flow does not drop, and

[0173] A fuel command curve 62 , which corresponds to the fuel flow rate command 9 .

[0174] also, Figure 3 Including the third curve Figure 3 C. In the third graph, the ordinate axis corresponds to the electric torque, and the abscissa axis corresponds to time.

[0175] Figure 3 The third curve Figure 3 C includes:

[0176] - an electric torque command curve 70, which corresponds to the electric torque command 11, and

[0177] A maximum electric torque curve 72 corresponding to the maximum electric torque that is not exceeded for the current engine speed.

[0178] Figure 3 The first curve Figure 3A. Second Curve Figure 3 B and the third curve Figure 3 C is synchronized so that, at each moment, a different graph gives the setpoint, measured value and / or command value at the operating point of the hybrid turbine engine 1 .

[0179] The fuel flow rate instruction 9 and the electric torque instruction 11 are generated in real time by the control method described above.

[0180] exist Figure 2 and Figure 3 In , the sequence of setpoints, measurements, and instructions contains so many points that for each point the rendering in the figure can be assimilated into a continuous curve.

[0181] First, it should be noted that the fuel flow command 9 and the electric torque command 11 vary independently. Specifically, the electric torque command 11 can be different from zero while the fuel flow command 9 is not in saturation, that is, the fuel flow command 9 does not coincide with the maximum fuel flow curve 60 or the minimum fuel flow curve 64.

[0182] For example, Figure 2 The fuel flow rate command curve 32 in φ is never in a saturated state, whereas the electric torque command curve 40 varies and takes a value different from zero.

[0183] When the two commands are generated simultaneously, it is possible to explore the operating speed of the hybrid turbine engine 1 with a wider range than that of the hybrid turbine engine of the related art and have better operation optimization.

[0184] Furthermore, the results shown show a relatively small hysteresis error. Hysteresis error corresponds to the time offset between the setpoint and the output quantity measurement. For example, hysteresis occurs when the measured rotational speed or angular velocity is delayed relative to the setpoint rotational speed or angular velocity by 20.

[0185] The rotational speed curve 22 is not offset or is slightly offset in time relative to the setpoint curve 20 , so that the hysteresis is small.

[0186] This benefit stems in particular from the fact that the control method corresponds to a type 2 “state feedback” architecture (ie comprising two integrators or two integral quantities, namely the deviation ENH associated with the last measured value 5 of the engine speed). k , and the sum of all deviations IENH k ) to calculate (in particular simultaneously) the fuel flow set point 9 and the electric torque set point 11.

[0187] The fuel flow setpoint 9 and the electric torque setpoint 11 enable the acceleration trajectory and / or deceleration trajectory of the engine speed to be tracked without lag when the tracking loop is activated and applied.

[0188] In fact, the computer-derived setpoints described thus far may or may not be used, depending on the flight phase. Depending on the flight phase, the requirement for a small hysteresis error is not always present. This is particularly true during the "cruise" flight phase, where there are fewer fast transients and a more appropriate corrector is preferred.

[0189] Although type 2 "state feedback" is not always applied, it is always active because it continuously calculates the set point. This allows, in particular, set point continuity when switching from one computer to another.

[0190] The control method and control device 3 according to the invention make it possible to meet the pilot's requirements by taking into account the engine's ability to accelerate or decelerate, in particular:

[0191] - limiting the acceleration time of a "normal" engine with surge margin to reduce the oversupply of fuel to the combustion chamber (also called overfeed) and thus limit the exhaust gas temperature (also called EGT) of the gases during acceleration to increase life; and

[0192] -Limiting thrust asymmetry between engines during acceleration to reduce aircraft drag and engine yaw effects.

Claims

1. A method for controlling a hybrid turbine engine (1), comprising the following steps: - Determine a series of deviations, each deviation being the difference between a measured value and a set point as follows: o the one measurement value is one measurement value from a series of measurements (5) of the rotational speed of the drive shaft of the hybrid turbine engine (1), o the one set point is one set point in a series of engine speed set points (7); - determining a change in the fuel flow and determining a change in the electric torque, said determinations being carried out in particular simultaneously and each of said determinations using: o the difference between the last measurement in a series of measurements and the second to last measurement in a series of measurements, the last deviation associated with the last measurement, and ο the sum of the deviations of a series of deviations; as well as - controlling the hybrid turbine engine (1) to vary the fuel flow rate by the determined variation of the fuel flow rate and to vary the electric torque by the determined variation of the electric torque.

2. The control method according to claim 1, wherein: During the determination of the change in fuel flow and the determination of the change in electric torque, the product of the gain matrix and a vector formed by the difference between the last measured value and the second to last measured value, the last deviation, and the sum of the deviations is determined.

3. The control method according to claim 2, wherein: The gain matrix is ​​obtained by interpolating between two reference matrices from a set of reference matrices to take into account the operating point of the hybrid turbine engine (1) associated with the last measured value.

4. A control device (3) for a hybrid turbine engine (1), comprising: - an input configured to receive a series of measured values ​​(5) of the engine speed of the hybrid turbine engine (1); a memory (31) configured to record a series of measured values ​​(5) and a series of rotational speed set points (7), - a calculator configured to: o Determine a series of deviations, each deviation being the difference between a measured value and a set point as follows: - said one measurement value is one measurement value from a series of measurement values ​​(5) of the engine speed of said hybrid turbine engine (1), - said one set point is one of a series of engine speed set points (7), o determining a change in the fuel flow rate and determining a change in the electric torque, in particular simultaneously determining a change in the fuel flow rate and determining a change in the electric torque, and each of said determining using: - the difference between the last measurement in a series of measurements and the second to last measurement in a series of measurements, - the last deviation associated with the last measured value, and - the sum of the deviations of a series of deviations; and - an output configured to provide instructions to the hybrid turbine engine (1).

5. A hybrid turbine engine (1) comprising a control device (3) according to claim 4.

6. An aircraft comprising a hybrid turbine engine (1) according to claim 5.

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