Method for controlling a hybridized turbine engine

Abstract

One aspect of the invention relates to a method for controlling a turbine engine (11) that minimizes the use of the fuel by using the fuel as a secondary power source for propulsion, and the electrical energy as a main power source for propulsion via an electric motor (M) introducing a torque into, or drawing a torque from, the low-pressure shaft (111) of the turbine engine (11). A first control loop makes it possible to determine a torque command supplied to the electric motor (M), and a second control loop connected to the first control loop determines a fuel command of the combustion chamber (103) of the turbine engine (11) from the torque command determined by the first control loop.

Description

DESCRIPTION TITLE: Method for controlling a hybridized turbomachine TECHNICAL FIELD OF THE INVENTION

[0001] The technical field of the invention is that of turbomachinery control.

[0002] The present invention relates to the field of aircraft propulsion, and more specifically to turbojet engines using an electric machine coupled to the low-pressure shaft to provide power to the low-pressure section, thus supplementing the power supplied by fuel combustion. The invention therefore concerns the control of hybridized turbomachinery with hybridization on the low-pressure section. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] Climate change is a major concern for many legislative and regulatory bodies worldwide. Indeed, various restrictions on carbon emissions have been, are being, or will be adopted by different countries. In particular, an ambitious standard applies to both new types of aircraft and those already in operation, requiring the implementation of technological solutions to bring them into compliance with current regulations. Civil aviation has been actively working for several years now to contribute to the fight against climate change.

[0004] Technological research efforts have already led to significant improvements in the environmental performance of aircraft. The Applicant takes into account factors impacting all phases of design and development to obtain aeronautical components and products that are less energy-intensive, more environmentally friendly, and whose integration and use in civil aviation have moderate environmental impacts, with the aim of improving aircraft energy efficiency. Consequently, the Applicant is continuously working to reduce its climate impact by employing methods and operating virtuous development and manufacturing processes that minimize greenhouse gas emissions to the minimum possible, thereby reducing the environmental footprint of its activities.

[0005] This sustained research and development work focuses in particular on the use of electrical technologies for propulsion. In this context, hybridized turbomachinery with hybridization on the low-pressure core is known from prior art.

[0006] Such a turbomachine is schematically represented in Figure 1. As is known, the turbomachine 10 comprises, from upstream to downstream in the direction of gas flow, a fan 100, a low-pressure compressor 101, a high-pressure compressor 102, a combustion chamber 103 which receives a WFCMD fuel flow control, a high-pressure turbine 104, a low-pressure turbine 105, and a primary exhaust nozzle 106. The low-pressure (LP) compressor 101 and the low-pressure turbine 105 are connected by a low-pressure shaft 111 and together form a low-pressure housing. The high-pressure (HP) compressor 102 and the high-pressure turbine 104 are connected by a high-pressure shaft 112 and together, with the combustion chamber, form a high-pressure housing. The blower 100, which is driven by the shaft BP 111, compresses the ingested air.This air is divided downstream of the blower 100 between a secondary airflow which is directed directly to a secondary nozzle (not shown) through which it is ejected to participate in the thrust provided by the turbomachine 10, and a so-called primary flow which enters the gas generator, consisting of the low pressure body and the high pressure body, and is then ejected into the primary nozzle 106.

[0007] To improve the response time of a turbomachine during transient phases (acceleration, deceleration, etc.), it has been proposed to equip the turbomachine with an electric motor to provide additional electrical torque to increase the turbomachine's speed without causing a pumping effect. For this purpose, patent application W02020 / 078720A1 describes a turbomachine for aircraft comprising an electric motor to draw power from the low-pressure shaft and inject power onto the high-pressure shaft. This patent application proposes a control architecture that prioritizes the use of fuel as the primary power source for propulsion and utilizes electrical energy as a secondary and complementary source to fuel when fuel utilization limits are reached.

[0008] Such a turbomachine might, for example, include: an electric motor forming a mechanical power injection device on at least one of the rotating shafts 111 and / or 112, a power extraction device on at least one of the rotating shafts, sized to extract excess power relative to the actuation requirement of the turbomachine's auxiliary systems, transforming the excess power into electrical energy, and an electrical storage means positioned between the power extraction device and the electric motor.

[0009] When the electric motor injects power onto the low-pressure shaft 111, the turbomachine is said to be "hybridized on the low-pressure body".

[0010] The electric motor and the low-pressure shaft are managed by a control system that dynamically adjusts the power supplied by the electric motor according to operating conditions and the power requirements of the turbomachine. Energy management becomes more complex with this hybrid configuration, requiring coordination between the electric motor and the low-pressure turbine to maximize energy conversion efficiency.

[0011] Therefore, there is a need to enable control of a hybridized turbomachine on the low-pressure body, minimizing fuel use while still being able to meet thrust objectives. SUMMARY OF THE INVENTION

[0012] The invention offers a solution to the problems mentioned above, by enabling turbomachine control that minimizes fuel use by using fuel as a secondary power source for propulsion, and electrical energy as the primary source for thrust control during certain phases of flight.

[0013] One aspect of the invention relates to a computer-implemented method for controlling an aircraft turbomachine, the turbomachine comprising at least: a combustion chamber, a low-pressure compressor, and a low-pressure turbine connected to said low-pressure compressor by a low-pressure rotating shaft, the turbomachine comprising an electric motor forming a device for injecting or extracting torque from the low-pressure rotating shaft, the method comprising: Determine a torque command supplied to the electric motor by a first torque control loop, including: acquiring a turbomachine thrust setpoint and a current value of a turbomachine thrust control parameter, determining the torque command as a function of the thrust setpoint and the current value of the turbomachine thrust control parameter, determining a fuel flow command in the combustion chamber by a second fuel control loop, including: comparing the torque command to a maximum torque applicable to the electric motor to obtain a torque difference, determining, by the second fuel control loop, the fuel command as a function of the torque difference, by calculating in closed loop the fuel flow required to bring the torque difference to a zero value.

[0014] By enabling the use of motive power supplied by an installed electric motor to directly transmit mechanical torque to the blower shaft, the invention uses fuel as a supplementary source to control the blower's rotation speed when the power limits of the electric machine are reached, thus minimizing fuel consumption.

[0015] Another advantage of the invention is that it enables the use of the HP body to drive an electrical power generator capable of supplying the electric motor that transmits torque to the fan for propulsion. The HP body is thus used as an electrical generator during low-thrust flight phases, maintaining the compressor within an optimized operating range.

[0016] Finally, the invention makes it possible, by minimizing fuel use, to limit the emission of polluting gases or, for military applications, to minimize the infrared signature of engines during certain phases of flight.

[0017] In addition to the features mentioned in the preceding paragraph, the method according to one aspect of the invention may have one or more complementary features from the following, considered individually or in all technically possible combinations: the turbomachine thrust control parameter is chosen from the turbomachine thrust, the turbomachine fan speed, the turbomachine EPR pressure ratio, and the power absorbed by the turbomachine fan. Determining the torque control involves comparing an intermediate torque control from the first control loop to a maximum torque applicable to the electric motor, with a final torque control determined as the minimum value between the intermediate torque control and the maximum torque applicable to the electric motor.The first control loop uses a correction network configured to determine the intermediate torque command based on the thrust setpoint and the current value of the turbomachine's thrust control parameter. The second control loop uses a correction network configured to determine the fuel setpoint based on the torque difference by calculating, in a closed loop, the fuel flow rate required to reduce the torque difference to zero. The process includes first maintaining the gas generator in an idle state by a third fuel regulation loop determining a fuel flow control in the combustion chamber. The process includes: maintaining the gas generator below a maximum operating temperature (N2MAX) by means of a fourth fuel loop that determines a fuel flow control in the combustion chamber. The method includes: maintaining the gas generator below a static pressure threshold PS3MIN by means of a fifth fuel loop determining a fuel flow control in the combustion chamber. A plurality of "minimum" and "maximum" operator blocks are configured to select a single final fuel flow control in the combustion chamber from among the fuel flow controls from the second and third fuel control loops.

[0018] Another aspect of the invention relates to an aircraft turbomachine comprising a turbomachine control processor configured to implement the process according to the invention, the turbomachine comprising at least: a blower positioned upstream of a gas generator and delimiting a primary flow and a secondary flow, said gas generator being traversed by the primary flow and comprising: a low pressure compressor, a high pressure compressor, a combustion chamber, a high pressure turbine connected to said high pressure compressor by a high pressure rotation shaft, and a low pressure turbine connected to said low pressure compressor by a low pressure rotation shaft and an electric motor forming a torque injection device on the low pressure rotation shaft.

[0019] Yet another aspect of the invention relates to an aircraft comprising the turbomachine according to the invention.

[0020] Yet another aspect of the invention relates to a computer program product comprising instructions which, when the program is executed by a computer, lead the computer to implement the process according to the invention.

[0021] Yet another aspect of the invention relates to a computer-readable data carrier on which the computer program product according to the invention is recorded.

[0022] The invention finds a particularly interesting application for limiting the ecological footprint of turbomachinery and in the military field, allowing a lower infrared signature than in the prior art.

[0023] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0024] The figures are presented for illustrative purposes only and are in no way limiting to the invention. Figure 1 shows a schematic representation of a prior art turbomachine, Figure 2 shows a schematic representation of a first embodiment of a turbomachine for implementing the process according to the invention, Figure 3 shows a schematic representation of a process according to one embodiment of the invention, Figure 4 shows a schematic representation of one embodiment of a process according to the invention, Figure 5 shows a schematic representation of a step in a process according to the invention, Figure 6 shows a schematic representation of a second embodiment of a method according to the invention, Figure 7 shows a schematic representation of an integrator in a second embodiment of a process according to the invention. DETAILED DESCRIPTION

[0025] Unless otherwise specified, the same element appearing on different figures has a unique reference.

[0026] Figure 2 shows a schematic representation of a turbomachine according to a first embodiment for the implementation of a process according to the invention.

[0027] The turbomachine 11 shown comprises, in a known manner, at least: a blower 100 positioned upstream of a gas generator 110 and delimiting a primary flow and a secondary flow, said gas generator 110 being traversed by the primary flow and comprising: a low-pressure compressor 101, a high-pressure compressor 102, a combustion chamber 103, a high-pressure turbine 104 connected to said high-pressure compressor 102 by a high-pressure rotation shaft 112, and a low-pressure turbine 105 connected to said low-pressure compressor 101 by a low-pressure rotation shaft 111 and

[0028] The turbomachine 10 has components identical to those of the prior art, and further includes an electric motor M, forming a torque injection device on the low pressure rotating shaft 111, configured to provide additional torque to the low pressure shaft 111.

[0029] The operation of the turbomachine 11 is controlled by an electronic unit P which obtains signals representing operating parameters of the turbomachine 11 to provide a fuel flow control WFCMD in the combustion chamber 103 and a torque control TRQCMD to the electric motor M. The operating parameters, also called turbomachine thrust control parameters, include, but are not limited to, at least one of the following parameters: the turbomachine thrust 11, the fan speed 100 of the turbomachine 11, the pressure ratio "EPR" (of The English term "Engine Pressure Ratio" (EPR) of the turbomachine 11, or the power absorbed by the fan 100 of the turbomachine 11 in the case of a turboprop, are parameters that allow control of the turbomachine 11's thrust and are well known to those skilled in the art. It is clear that other thrust control parameters could be used within the framework of this invention.

[0030] The electronic entity P is for example a processor P for controlling the engine M, for example a computer called "FADEC", for "Full Automatic Digital Engine Control" (from the English "Fully Automatic Digital Engine Control").

[0031] The processor P is configured to implement a method for controlling the turbomachine 11. Alternatively, the method can be implemented by a computer included in the turbomachine 11 or in an aircraft carrying the turbomachine 11, the computer communicating with the processor P.

[0032] A "computer" implementing the method according to the invention comprises at least one processor and one memory. The memory includes instructions which, when executed by the processor, cause the processor to implement the method according to the invention. In the course of implementing the method, the processor may store additional data in the memory or delete data stored in the memory.

[0033] The computer and the turbomachine can, for example, be embedded in an airborne system, for example in an aircraft.

[0034] As illustrated in Figure 4, the processor P includes a control system comprising a first loop B1 for regulating the torque control TRQCMD to be applied to the electric motor M for regulating the engine thrust control parameter, hereafter referred to as the "first thrust control loop B1", and a second control loop B2 determining a fuel flow control delta AWF1, enabling the determination of a fuel control WFCMD in the combustion chamber 103, hereafter referred to as the "second fuel loop B2".

[0035] The control system includes a fuel limitation to maintain the gas generator at idle. For this purpose, the control system The fuel control system may include a third control loop, called the "third fuel loop B3," which provides a second fuel control value as its output, monitoring a different parameter than the second fuel loop B2. The second fuel loop B2 can be configured to determine a fuel control delta AWF1 based on a torque command TRQCMD determined by the first torque loop B1, while the third fuel loop B3 can be configured to determine a fuel control delta AWF3 to control the N2 speed of the low-pressure shaft 111 to maintain it in an idle state N2IDLE. One of these fuel control deltas, AWF1 or AWF3, will then be selected by a network of "Min" and / or "Max" operators described later.An integrator 11 included in the control system then allows the selected fuel control delta to be integrated to obtain a fuel control and control of the turbomachine 11.

[0036] Figure 3 shows a schematic representation of an embodiment of the method 20 for controlling a hybridized turbomachine according to the invention.

[0037] This process 20 comprises at least two steps 21 and 22.

[0038] In a first step 21, the computer implementing the process 20 determines a torque command TRQCMD to be supplied to the electric motor M, and therefore to be applied to the low-pressure shaft 111. This determination is carried out by the first torque regulation loop B1.

[0039] For this purpose, and as schematically represented in Figure 4, the torque loop B1 receives a current value of a thrust control parameter Param of the turbomachine 11, and a setpoint value of this parameter to achieve a desired power of the turbomachine 11. In the following description, the example of the speed (rotational speed) of the shafts of the turbomachine 11 will be chosen as the thrust control parameter of the turbomachine 11, but the invention covers any thrust control parameter of the turbomachine 11, for example thrust, EPR etc. as described previously.

[0040] Thus, in step 21, the first loop B1 receives a current operating speed N1 of the turbomachine 11, and a setpoint N1 C for the operating speed of the turbomachine 11 to be reached, for example defined by the position of the control lever manipulated by the pilot of the aircraft including the turbomachine 11. N1 is in fact the regime of the low pressure shaft 111 which drives the fan 100.

[0041] The RC1 correction network included in the first torque loop B1 is configured to determine, in substep 211, a TRQI CMDI torque command based on the target turbomachine speed N1 C and the current speed N1. This RC1 correction network must include a The integration of the type in order to be able to cancel a permanent position error known to a person skilled in the art. For example, the RC1 correction network may have the following transfer function: , with Te the period of Calculation of processor P, and T and K the controller gains known to those skilled in the art. With the presented transfer function, the RC1 controller network combines the characteristics of proportional and integral controllers.

[0042] At the output of the RC1 correction network, an intermediate torque command TRQI CMD is obtained. This command corresponds to the torque control for the N1 C setpoint before saturation by the RC1 correction network, to be supplied to the motor M so that the low-pressure shaft 111 reaches the N1 C setpoint speed.

[0043] From this intermediate torque command TRQI CMD, the final torque command TRQCMD to be applied to the electric motor M is determined in a substep 212. The torque command from the first torque regulation loop B1 is called "intermediate torque command TRQ1 CMD", while the torque command finally applied to the motor is called final torque command TRQCMD.

[0044] To achieve this, the final torque command TRQCMD supplied to the electric motor M is chosen as the minimum value between the intermediate torque command TRQI CMD and a maximum torque value TRQMAX applicable to the motor M. This maximum torque value might be a torque injection limit, a machine or transmission chain capacity limit, or any other limit. In one example, the maximum torque value TRQMAX protects the electric motor M by comparing the intermediate torque command TRQ1 CMD with a maximum torque limit applicable to the motor M. Specifically, when the intermediate torque command TRQI CMD exceeds the maximum torque value TRQMAX, the motor M is not protected. If the intermediate torque control value TRQI CMD is applicable to motor M, it would entail a risk, for example, of damaging motor M, and therefore it is this maximum torque value TRQMAX applicable to motor M that will be applied to motor M. Conversely, when the intermediate torque control TRQI CMD is less than the maximum torque value TRQMAX applicable to motor M, it can be supplied to motor M as the final torque control TRQCMD.

[0045] For example, the electric motor M can be sized to provide most of the thrust during cruise only, and therefore at high altitudes, thus requiring little power. But not for takeoff and the climb phase, which generally require much higher power. In this case, the fuel, delivered via the high-pressure cylinder, will cleverly supplement the power supply to ensure these operating phases.

[0046] The process 20 also includes a step 22 of determining a fuel flow control delta AWF1 in the combustion chamber 103 by the second fuel regulation loop B2.

[0047] The second torque control loop, B2, aims to use turbomachine fuel sparingly. Therefore, a fuel control delta, AWF1, is only provided by the second loop, B2, when the TRQCMD torque control is limited within its operating range, i.e., for example, when the intermediate torque control, TRQI CMD, exceeds the maximum torque, TRQMAX, of the electric motor M. Consequently, the second fuel loop, B2, includes a first comparator that calculates the difference between the intermediate torque control, TRQI CMD, and the limit switch of the electric motor M, for example, the maximum torque, TRQMAX, of the electric motor M. This yields a torque difference, ATRQ, which, if positive, corresponds to the torque missing to reach the setpoint, i.e., a controlled torque deficit to ensure thrust control.If this value is negative, then the intermediate torque control TRQ1 CMD is less than the maximum torque TRQMAX, and the invention then allows the gas generator to be returned to an idle state, as described later in the description.

[0048] The second fuel loop, B2, includes a correction network, RC2, which takes the torque difference ATRQ as input and provides a fuel flow control delta, AWF1, as output. The correction network, RC2, is configured to attempt to bring the torque difference ATRQ to zero. Thus, the correction network, RC2, will increment the fuel flow control delta, AWF1, when the torque difference ATRQ is positive, and it will provide a fuel flow control delta, AWF1, allowing integrator 11 to decrement the fuel flow control delta, WFCMD, if necessary, when the torque difference ATRQ is negative.

[0049] Thus, step 22 comprises a first substep 221 comparing the torque control TRQCMD to a maximum torque TRQMAX applicable to the electric motor M to obtain a torque difference ATRQ, and a second substep 222 determining, by the second fuel control loop B2, the fuel control delta AWF1 as a function of the torque difference ATRQ, by calculating in a closed loop the fuel flow rate required to reduce the torque difference ATRQ to zero. The fuel control delta AWF1 will then be integrated to obtain a final fuel control WFCMD.

[0050] In a second embodiment of the method according to the invention, the control system comprises a plurality of fuel control loops B2 to B5. Each fuel control loop B2 to B5 provides at output a different AWF fuel control delta, determined as a function of a different parameter monitored by the respective fuel control loop.

[0051] In this second embodiment, the first torque loop B1 and the second fuel loop B2 are identical to the first torque loop B1 and the second fuel loop B2 of the first embodiment. In this second embodiment, the control system includes at least one second fuel control loop, for example, the fuel control loop B3. Figure 6 shows three additional fuel control loops B3 to B5, but the invention covers any number of fuel control loops, not limited to the example shown in Figure 6. Each control loop includes at least one correction network RC2, RC3, RC4, and RC5, which determines a fuel control delta based on a difference value (of engine speed, torque or pressure for example) that it receives at the input.

[0052] For example, RC2 to RC5 controllers can be phase-lead type controllers whose transfer function can be, but not limited to, one of the following forms: Transfer function Transfer function

[0053] With Te being the processor's computation period, P, T, and K being the controller gains known to those skilled in the art and not limiting the invention. The form of the controller networks (CNs) is not limiting the invention and can take any other form known to those skilled in the art, such as PI, PID, state-feedback controllers, etc.

[0054] In the example shown in Figure 6, the third fuel control loop B3 monitors a speed parameter N2 of the high-pressure shaft 112 and ensures that it reaches an idle speed setpoint N2IDLE. The third fuel control loop B3 outputs a fuel control delta AWF3 to maintain this idle speed criterion N2IDLE. This fuel control loop B3 allows the gas generator 110 to be kept in an idle state, enabling its economical use and prioritizing the use of the electric motor M via the first torque control loop B1. The gas generator 110 is thus ready to supplement the power supplied by the electric motor M via the torque control TRQCMD in the event that the TRQCMD torque control encounters a limitation.

[0055] In the example shown in Figure 6, the fourth fuel control loop B4 monitors a speed parameter N2 of the high-pressure shaft 112 and ensures that it does not exceed a speed threshold N2MAX. The fourth fuel control loop B4 outputs a fuel control delta AWF4 to maintain compliance with this N2MAX speed threshold criterion.

[0056] In the example in Figure 6, the fifth fuel regulation loop B5 monitors a static pressure parameter Ps3 measured at the outlet of combustion chamber 103, and ensures that it does not fall below a threshold PS3MIN. The fifth fuel loop B5 provides at the output a fuel control delta AWF5 allowing this minimum static pressure criterion PS3MIN to be met.

[0057] Thus, in the example shown in Figure 6, the control system must manage four different fuel demand deltas, AWF1, AWF3, AWF4, and AWF5, each linked to a different requirement. Therefore, in any multi-loop fuel control embodiment, it is necessary to use a network of Min and Max operators, as shown in Figure 6, to select a fuel demand delta from among those obtained.

[0058] This is achieved in step 23 of selecting a fuel control delta from a plurality of fuel control deltas from different fuel regulation loops.

[0059] For example, in Figure 6, a "Max" operator allows the selection of the highest fuel control delta value among the control deltas AWF1 from the second loop B2, AWF3 from the third loop B3, and AWF5 from the fifth loop B5. Thus, if the value of the fuel control delta AWF1 from the second loop B2, which seeks to compensate for the lack of torque of engine M, is less than the value of the fuel control delta AWF3 from the third loop B3, which regulates the turbomachine 11 at idle speed, the fuel control delta AWF1 will not be applied to the turbomachine 11, and it will be maintained at idle speed.

[0060] The output of the "Max" operator is the input of a "Min" operator, the "Min" operator also taking as input the fuel control delta AWF5 from the fifth loop B5. This allows the selection of the lower of the fuel control delta values ​​from the "Max" operator and the AWF4 fuel control delta from the fourth loop B4. Thus, if the control delta value from the "Max" operator is less than the AWF4 fuel control delta value from the third loop B4, which regulates the turbomachine 11 to limit N2 to a maximum speed N2MAX of the high-pressure shaft 112, the command from the "Max" operator will be applied to the turbomachine 11. Therefore, if the command from the Max operator is applied, it means that N2 complies with the N2MAX limitation. If AWF4 is selected, it indicates The command from the Max operator tends to exceed N2MAX, which is why the command from the Max operator is greater than AWF4. The Min operator then allows selection of the command that maintains the N2 regime at the N2MAX value as long as the delta command from the Max operator does not fall below AWF4.

[0061] Finally, the control system in Figure 6 includes a common integrator of the fuel loops 11, which transforms the fuel control delta selected by the Min / Max operator network in kg / h / s into a fuel flow control in kg / h. This integrator 11 is schematically represented in Figure 7. Thus, in a step 24 of process 2, the fuel control delta selected in step 23 or the fuel control delta from loop B2 is integrated to obtain a final fuel flow control WFCMD.

[0062] In integrator 11, fuel control limitations are provided to ensure the maintenance of the high-pressure compressor's operating conditions with respect to "WFSTALL" pumping and "WFEXT" combustion chamber shutdown. These limitations may arise from so-called "C / P" (for Torque / Power) laws known to those skilled in the art, for example:

[0064] With WFCMD the fuel flow rate injected into the combustion chamber (in Kg / h), N2 the rotation speed of the high-pressure shaft, Ps3 the static pressure in the combustion chamber (in Bars), T25 the total temperature at the outlet of the turbomachine (in K), PT2 the total pressure at the inlet of the blower 100 (in Bars).

[0065] As shown in Figure 8, the integrator 11 includes a multiplier block, which multiplies the fuel control input by a time parameter Te to generate a term proportional to Te. The integrator 11 includes Min and Max blocks that limit the output between WFSTALL and WFEXT to prevent extreme values ​​that could cause malfunctions or damage to the turbomachine 11. The integrator 11 further includes a delay block. taking as input the previous outputs of integrator 11, and as initial value WFEXT. The feedback loop of integrator 11 thus relies on this delay block to store the previous values, and uses these previous values ​​to adjust The output is continuously monitored. This allows past errors to be tracked and necessary corrections to be accumulated. The integrator 11 thus ensures stable and optimized real-time engine regulation, providing a final WFCMD fuel flow control output to the combustion chamber 103.

[0066] In the second embodiment, thanks to the fuel flow control loops B3 to B5, the high-pressure body will be maintained at all times within its operating range, regardless of the fuel control delta AWF1 resulting from the second loop B2, which aims to cancel the torque difference ATRQ. The final fuel flow control WFCMD will therefore either supplement the thrust control, ensure the high-pressure body remains operational, or provide the necessary power to the torque loop B1 to maintain thrust control.

Claims

DEMANDS

1. A computer-implemented method (20) for controlling an aircraft turbomachine (11), the turbomachine (11) comprising at least: a combustion chamber (103), a low-pressure compressor (101) and a low-pressure turbine (105) connected to said low-pressure compressor (101) by a low-pressure rotating shaft (111), the turbomachine comprising an electric motor (M) forming a device for injecting or extracting torque on the low-pressure rotating shaft (111), the method comprising: - Determine (21) a torque command (TRQCMD) supplied to the electric motor (M) by a first torque control loop (B1), comprising: o acquiring a thrust setpoint of the turbomachine (11) and a current value of a thrust control parameter of the turbomachine (11), o determining the torque command (TRQCMD) as a function of the thrust setpoint and the current value of the thrust control parameter (Param) of the turbomachine (11), - determine (22) a fuel flow control (WFCMD) in the combustion chamber (103) by a second fuel control loop (B2), comprising: o compare the torque control (TRQCMD) to a maximum torque (TRQMAX) applicable to the electric motor (M) to obtain a torque difference (ATRQ), o determine, by the second fuel control loop (B2), the fuel control (WFCMD) as a function of the torque difference (ATRQ), by calculating in closed loop the fuel flow required to bring the torque difference (ATRQ) back to a zero value.

2. A method (20) according to the preceding claim, wherein the turbomachine thrust control parameter (Param) is selected from the turbomachine thrust, the turbomachine fan speed, the ratio EPR turbomachine pressure, the power absorbed by the turbomachine blower.

3. Method (20) according to any one of the preceding claims wherein determining the torque control (TRQCMD) comprises comparing an intermediate torque control (TRQI CMD) from the first control loop (B1) to a maximum torque (TRQMAX) applicable to the electric motor (M), a determined final torque control (TRQCMD) being the minimum value among the intermediate torque control (TRQI CMD) and the maximum torque (TRQMAX) applicable to the electric motor (M).

4. Method (20) according to any one of the preceding claims wherein the first control loop (B1) uses a correction network (RC1) configured to determine the intermediate torque control (TRQI CMD) as a function of the thrust setpoint and the current value of the thrust control parameter (Param) of the turbomachine (11).

5. A method (20) according to any one of the preceding claims comprising previously: - maintain the gas generator (110) in an idle state by a third fuel regulation loop (B3) determining a fuel flow control (AWF3) in the combustion chamber (103).

6. A method (20) according to claim 5 wherein a plurality of "minimal" and "maximal" operator blocks are configured to select a single final fuel flow control in the combustion chamber (103) from among the fuel flow controls (WFI CMD, WF3CMD) from the second and third fuel control loops (B2, B3).

7. Aircraft turbomachine (11) comprising a control processor (P) for the turbomachine (11) configured to implement the method (20) according to any one of the preceding claims, the turbomachine (11) comprising at least: - a blower (100) positioned upstream of a gas generator (110) and defining a primary flow and a secondary flow, - said gas generator (110) being traversed by the primary flow and comprising: o a low pressure compressor (101 ), o a high pressure compressor (102), o a combustion chamber (103), o a high pressure turbine (104) connected to said high pressure compressor (102) by a high pressure rotation shaft (112), and o a low pressure turbine (105) connected to said low pressure compressor (101 ) by a low pressure rotation shaft (111 ) and - an electric motor (M) forming a device for injecting and collecting torque on the low pressure rotation shaft (111 ).

8. Aircraft comprising the turbomachine (11) according to claim 7.

9. Product computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method (20) according to any one of claims 1 to 6.

10. Computer-readable data carrier on which the computer program product according to claim 9 is recorded.

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