CONTROL SYSTEM FOR A HYBRID TURBOMACHINE BY OBSERVER WITH RECONFIGURATION BY CONTROL SATURATION DETECTION

Abstract

Control system for a hybrid turbomachine (2) provided with at least one rotation speed sensor, comprising: a means (3) for determining a rotation speed setpoint, an observation means determining a control disturbance vector, a detection means (6) emitting a fault signal when a value of the disturbance vector is greater than a predetermined threshold, and a means (11) for calculating the torque commands of the hybrid turbomachine (2) as a function of the rotation speed setpoint and measurement, and of a fault signal, a means (12a) for saturating the torque command to the electrical part (2a) of the hybrid turbomachine as a function of the fault signal, a subtractor (13a) emitting the fault signal in the event of a difference between the torque command to the electrical part (2a) of the turbomachine before and after saturation. Figure for the abstract: Fig 2

Description

Title of the invention: SYSTEM FOR CONTROLLING A HYBRID TURBOMACHINE BY OBSERVER WITH RECONFIGURATION BY SATURATION DETECTION ORDER Technical field

[0001] The technical field of the invention is control systems, and more specifically observer control systems. Previous techniques

[0002] A turbomachine comprises a low-pressure air intake portion and a high-pressure turbine-type portion in which fuel is injected and undergoes combustion. In the low-pressure portion, the turbomachine comprises a fan, a propeller, or turbine blades connected to at least one drive shaft. In the high-pressure portion, it comprises turbine blades connected to at least one drive shaft.

[0003] A hybrid turbomachine comprises an electrical part provided with at least one electrical machine connected to one of the transmission shafts and a thermal part also connected to one of the transmission shafts.

[0004] In particular, a turbomachine, in particular of the double flow type ("turbofan" in English) or turboprop, comprises a low pressure transmission shaft connected to the propeller or to the fan ("fan" in English), and a high pressure transmission shaft connected to the turbine.

[0005] In the context of a hybridization, a first electric machine is coupled to the low-pressure transmission shaft and, optionally, a second electric machine is coupled to the high-pressure transmission shaft. In one embodiment, each electric machine is disengageably coupled so that it can be disconnected from the corresponding transmission shaft. In another embodiment, the power supply phases of each electric machine are disconnectable, each machine then remaining connected to the corresponding transmission shaft. When the electric machines are disengaged or disconnected, the hybridized turbomachine operates like a conventional turbomachine.

[0006] When at least one electric machine is connected or engaged, the hybrid turbomachine operates through the torque provided by the at least one connected or engaged electric machine, and the torque provided by the combustion of the fuel in the thermal part driving the turbine.

[0007] Such a hybrid turbomachine is advantageous due to fuel savings. generated.

[0008] In the context of the electrical hybridization of a turbomachine, in particular a double-body double-flow, it is desired to act on the rotation speeds through three controls, the fuel flow in the combustion chamber of the thermal part (traditional control for actuating the thermal machine), the torque delivered by the first electric machine and the torque delivered by the second electric machine. However, without measuring the rotation speed of the electric machines, it is not possible to determine the presence of a fault and to take it into account when determining the controls.

[0009] This problem is also present for a turbojet engine having only one electric machine.

[0010] From the state of the prior art, we know the document FR2954020 describing the control of a permanent magnet synchronous machine, based in particular on an observer technique.

[0011] However, this document does not describe the control of a hybrid system without access to the rotation speed of the electric machines. Statement of the invention

[0012] Climate change is a major concern for many legislative and regulatory bodies around the world. Indeed, various restrictions on carbon emissions have been, are being, or will be adopted by various states. In particular, an ambitious standard applies both to new types of aircraft and those in circulation requiring the implementation of technological solutions in order to make them compliant with current regulations. Civil aviation has been mobilizing for several years now to make a contribution to the fight against climate change.

[0013] Technological research efforts have already made it possible to significantly improve the environmental performance of aircraft. The Applicant takes into consideration the impact factors in all phases of design and development to obtain less energy-intensive, more environmentally friendly aeronautical components and products whose integration and use in civil aviation have moderate environmental consequences with the aim of improving the energy efficiency of aircraft.

[0014] Consequently, the Applicant is constantly working to reduce its negative climate impact by using methods and operating virtuous development and manufacturing processes and minimizing greenhouse gas emissions to the minimum possible in order to reduce the environmental footprint of its activity.

[0015] This sustained research and development work covers new generations of aircraft engines, the lightening of aircraft, in particular through the materials used and lighter on-board equipment, the development of the use of electrical technologies to ensure propulsion, and essential complements to technological progress.

[0016] To this end, the invention is the result of technological research aimed at very significantly improving the performance of aircraft and, in this sense, contributes to reducing the environmental impact of aircraft. For this purpose, the subject of the invention is a control system for a hybridized turbomachine comprising at least one electrical part and one thermal part and at least one transmission shaft connected to at least one of the electrical and thermal parts, said hybridized turbomachine being provided with at least one sensor for measuring the rotational speed of said at least one transmission shaft, the control system comprising a means for determining at least one rotational speed setpoint as a function of at least one request. The control system comprises:

[0017] a. a means for observing the hybridized turbomachine by means of observer modeling configured to determine a control disturbance vector,

[0018] b. a means for detecting a fault as a function of the disturbance vector of the controls received from the observation means, configured to emit a fault signal when at least one of the values ​​of the disturbance vector is greater than a predetermined threshold, and

[0019] c. a means for determining commands comprising:

[0020] • a means of calculating torque commands to the turbomachine hybridized according to a rotation speed setpoint received from the rotation speed setpoint determination means and a measurement of the rotation speed of the hybridized turbomachine and a fault signal,

[0021] • a first means of saturating the torque command to the part electrical of the hybrid turbomachine, depending on the failure signal,

[0022] • a saturation subtractor configured to realize the difference between the torque control to the electrical part of the turbomachine before and after saturation by the first saturation means, and to emit the fault signal in the event of a difference.

[0023] The means for determining orders may comprise:

[0024] • a rotation speed subtractor, determining the difference between the setpoint rotation speed regulation of the hybrid turbomachine and the corresponding rotation speed measurement.

[0025] • a calculation means configured to determine the torque control of the part electric part of the hybrid turbomachine and the fuel injection control of the thermal part of the hybrid turbomachine according to a model and the difference in rotation speed determined by the rotation speed subtractor.

[0026] The turbomachine may comprise a low pressure (LP) part provided with a rotation speed sensor of the LP part and a high pressure (HP) part being provided with a rotation speed sensor of the HP part, the electrical part of the turbomachine comprising an independent LP electrical part and an HP electrical part, and in which:

[0027] • the means for determining rotation speed instructions determines the rotation speed instructions for the HP electrical part and the LP electrical part based on at least one request,

[0028] • the means for determining commands comprises a speed subtractor of BP rotation determining a BP deviation signal as a function of the deviation between the rotation speed of the BP part and the rotation speed command of the BP part, and an HP rotation speed subtractor determining an HP deviation signal as a function of the deviation between the rotation speed of the HP part and the rotation speed command of the HP part,

[0029] • the calculation means determining an HP torque setpoint for the HP electrical part of the turbomachine as a function of the HP deviation signal, a BP torque setpoint to the BP electrical part of the turbomachine as a function of the BP deviation signal, and a torque setpoint to the thermal part of the turbomachine as a function of the BP deviation signal and the HP deviation signal,

[0030] • the means of fault detection as a function of the disturbance vector of the commands received from the observation means are configured to emit a failure signal specific to the LP electrical part or to the HP electrical part of the hybridized turbomachine when the corresponding value of the disturbance vector is greater than the predetermined threshold,

[0031] • the means for determining commands comprising a means for saturating the torque control of the BP electrical part and a means of saturating the torque control of the HP electrical part, the means of saturating the torque control of the BP electrical part receiving the fault signal of the BP electrical part, the means of saturating the torque control of the HP electrical part receiving the fault signal of the HP electrical part,

[0032] • the means for determining orders also comprising a subtractor BP saturation subtractor emitting a fault signal when the torque control values ​​of the BP electrical part before and after saturation differ, and an HP saturation subtractor emitting a fault signal when the torque control values ​​of the HP electrical part before and after saturation differ,

[0033] • the calculation means receiving the fault signals from the BP saturation subtractor and the HP saturation subtractor so as to modify the distribution of rotation speed instructions according to the identified fault.

[0034] The turbomachine may be equipped with a sensor for measuring the static pressure at the outlet of the high pressure part of the hybridized turbomachine, and the control system then comprising:

[0035] • the means for determining rotation speed instructions determining the static air pressure instructions at the outlet of the high pressure part of the hybrid turbomachine to the thermal part based on at least one request,

[0036] • the means for determining commands comprising a subtractor from the measurement of the static air pressure at the outlet of the high pressure part of the hybrid turbomachine and of the static air pressure control at the outlet of the high pressure part of the hybrid turbomachine,

[0037] • the calculation means determining a fuel injection instruction according to of the static air pressure difference signal at the output of the high pressure part of the hybrid turbomachine,

[0038] • the means of fault detection as a function of the disturbance vector of the commands received from the observation means being configured to emit a fault signal specific to the thermal part when the corresponding value of the disturbance vector is greater than the predetermined threshold,

[0039] • the second means of saturating the fuel injection control being configured to receive the thermal part failure signal,

[0040] • the means for determining commands also comprising a second fuel injection saturation subtractor emitting a fault signal when the fuel injection values ​​of the thermal part before and after saturation differ,

[0041] • the calculation means receiving the fault signal from the second subtractor of its fuel injection control so as to modify the distribution of the instructions between the thermal part and the electrical part of the hybrid turbomachine with a view to determining the torque instructions and the fuel injection control.

[0042] A fault signal may only be emitted if the value of the determined disturbance vector greater than the predetermined threshold remains greater than said predetermined threshold for a predetermined duration.

[0043] The fault detection signal can be transmitted to the hybridized turbomachine so as to decouple the electrical part of the turbomachine, the LP electrical part or the HP electrical part of the hybridized turbomachine.

[0044] The means for determining commands may comprise a second means of saturation of the fuel injection control to the thermal part of the hybrid turbomachine.

[0045] The invention also relates to a method for controlling a hybrid turbomachine comprising at least one electrical part and one thermal part and at least one transmission shaft connected to at least one of the electrical and thermal parts b, said hybrid turbomachine being provided with at least one sensor for measuring the rotation speed, the control method, particularly advantageous for the purpose of reducing the environmental impact of aircraft, comprising the following steps:

[0046] a. determination of at least one rotation speed setpoint as a function of at least one request

[0047] b. determination of a control disturbance vector by means of observer modeling of the hybridized turbomachine,

[0048] c. emitting a fault signal when at least one of the values ​​of the disturbance vector is greater than a predetermined threshold, and

[0049] d. determination of orders comprising the following sub-steps:

[0050] • calculation of torque commands to the hybridized turbomachine in function of a rotation speed setpoint, a measurement of the rotation speed of the hybrid turbomachine and a fault signal,

[0051] • saturation of the torque control to the electrical part of the turbine hybridized machine, depending on the fault signal,

[0052] • transmission of a fault signal to the calculation means in the event of difference between the torque command to the electrical part of the turbomachine before and after saturation.

[0053] Another object of the invention is an aircraft equipped with a hybrid turbomachine and a control system or a control means configured to carry out the control method as described above. Brief description of the drawings

[0054] Other aims, characteristics and advantages of the invention will appear on reading the following description, given solely by way of non-limiting example and made with reference to the appended drawings in which:

[0055] - figure [Fig.l] illustrates the main elements of a control system according to the invention,

[0056] - figure [Fig.2] illustrates the main elements of a means of calculating torque commands to the hybrid turbomachine according to the invention,

[0057] - figure [Fig.3] illustrates the main elements of a means of calculating torque commands for the hybrid turbomachine according to the invention according to another embodiment, and

[0058] - Figure [Fig.4] illustrates the detection of a defect and the accommodation of this defect at level of the instructions of the hybrid turbomachine. Detailed description

[0059] Figure [Fig.l] illustrates a control system 1 of a hybridized turbomachine 2, comprising an electrical part 2a comprising the at least one electrical machine and a thermal part 2b corresponding to the turbine driven by the combustion of the injected fuel. The electrical part 2a and the thermal part 2b are each coupled to at least one transmission shaft of the turbomachine.

[0060] The control system comprises a means 3 for determining rotation speed setpoints as a function of external requests and a means 4 for determining torque commands to the hybridized turbomachine 2 as a function of a rotation speed setpoint received from the means 3 for determining rotation speed setpoints and a measurement of the rotation speed of the transmission shaft of the hybridized turbomachine 2. The determined commands comprise a fuel flow command to the thermal part 2b of the hybridized turbomachine, and a torque command to the electrical part 2a of the hybridized turbomachine.

[0061] The control determining means 4 is also configured to perform fault adaptation when a fault is detected on the electrical part 2a of the turbomachine. Other control systems can monitor the occurrence of faults on the thermal part of the hybridized turbomachine. In the event of a fault on the thermal part of the hybridized turbomachine, fault detection and accommodation are frozen. In such a situation, it cannot be determined whether the detected torque error is due to a fault in the electrical part or the thermal part of the hybridized turbomachine (double fault situation).

[0062] In a generic embodiment, the electrical part 2a of the hybridized turbomachine comprises an electric machine coupled to the transmission shaft.

[0063] The control system 1 comprises a means 5 for observing the hybridized turbomachine 2 by means of observer modeling, as a function of the rotation speed of the transmission shaft of the low pressure part, the rotation speed of the transmission shaft of the high pressure part, the fuel flow control of the thermal part 2b of the hybridized turbomachine and the torque control of the electrical part 2a of the hybridized turbomachine.

[0064] In a particular embodiment, the electrical part 2a of the hybridized turbomachine comprises a first electrical machine coupled to the low-pressure transmission shaft and a second electrical machine coupled to the transmission shaft.

[0065]

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[0073] high pressure. The control system 1 comprises a means 5 for observing the hybridized turbomachine 2 by means of observer modeling, as a function of the rotational speed of the transmission shaft of the low pressure part, the rotational speed of the transmission shaft of the high pressure part, the fuel flow control of the thermal part 2b of the hybridized turbomachine, the torque control of the electrical part linked to the low pressure part of the hybridized turbomachine and the control of the electrical part linked to the high pressure part of the hybridized turbomachine. The modeling of the observer and the control structure described below can be adapted according to the chosen implementation mode. The observer of the hybridized turbomachine 2 is realized using a dynamic model of the turbomachine expressed in state representation. We first define the state representation of the unperturbed hybrid machine. [Math.l] f A i+î = Ax k + Bu k [ y k ^Cx k + From k The dynamic model of equation [Math 1] can be modified to account for disturbances in the system. [Math.2] xk+ ! ~ ^k + 5 ( lik + ) 3'^ = ^xk + ^llk The perturbed system thus obtained can be modified so as to be increased. [Math.3] Xk+ j — AaugXk + BaugUk ^k = CaugXk + DaUgllk AI B \ [o A pert} CaUg={l 0) Daug — D HAS pert - dynamics of disturbance

[0074] Finally, the augmented system can be modified to take into account the observation.

[0075] [Math.4] ~ AaugX], 4- BaugUk + L( y- y ) * )■' = CaugX^ + DaugU^ . K

[0076] With

[0077] x: state vector of the hybridized turbomachine

[0078] x ; estimated state vector of the hybridized turbomachine

[0079] u: vector of commands

[0080] d: command disturbance vector

[0081] y: measured outputs of the hybridized turbomachine

[0082] y: estimated outputs of the hybridized turbomachine

[0083] A: state matrix

[0084] B: control matrix

[0085] C: observation matrix

[0086] D: direct action matrix

[0087] Aaug: augmented system state matrix

[0088] Baug: augmented system control matrix

[0089] Caug: observation matrix of the augmented system

[0090] DaUg: direct action matrix of the augmented system

[0091] Apert: matrix of the dynamics of the disturbance

[0092] L: observer gain matrix

[0093] The control vector comprises the fuel flow rate of the thermal part 2b of the hybridized turbomachine, the torque control of the electrical part linked to the low pressure part of the hybridized turbomachine and the control of the electrical part linked to the high pressure part of the hybridized turbomachine.

[0094] The measured outputs include the rotational speed of the low pressure part drive shaft and the rotational speed of the high pressure part drive shaft.

[0095] The control system 1 comprises a means 6 for detecting a fault as a function of the control disturbance vector received from the observation means 5.

[0096] Fault detection is performed based on the disturbance vector received from the observer. Note that all values ​​of the disturbance vector are calculated at each calculation step.

[0097] To achieve this, it is determined whether at least one of the values ​​of the disturbance vector remains above a predetermined threshold for a predetermined duration. Alternatively, each value of the disturbance vector is compared to a threshold specific to it. If this is the case, a failure of the electrical part of the tur- hybridized bomachine is identified.

[0098] The threshold value and the predetermined duration are set according to the sensitivity that one wishes to give to the system. The lower these values ​​are, the faster the detection but risks giving rise to false detections.

[0099] When a fault is detected, the fault detection means 6 emits a fault signal to the control determination means 4, to the rotation speed setpoint determination means 3 and to the electrical part 2a of the hybrid turbomachine.

[0100] When a fault is detected, the controls of the hybridized turbomachine 2 must be modified so that the total required torque is obtained. In other words, the thermal part 2b of the hybridized turbomachine is controlled so that it compensates for the torque not produced by the electrical part 2a of the hybridized turbomachine 2.

[0101] Figure [Fig.2] illustrates the main elements of the control determination means 4, configured to carry out the failure adaptation in addition to the determination of the controls of the hybridized turbomachine 2.

[0102] A regulation instruction for the rotation speed of the hybridized turbomachine originating from the means 3 for determining rotation speed instructions and a measurement of the rotation speed of the hybridized turbomachine 2 are received at the input of the means 4 for determining commands.

[0103] The control determination means 4 comprises a rotation speed subtractor 10a, determining the difference between the rotation speed regulation setpoint of the hybridized turbomachine and the corresponding rotation speed measurement.

[0104] The rotation speed difference determined by the rotation speed subtractor 10a is transmitted to a calculation means 11 configured to determine the torque commands of the electrical part 2a of the hybridized turbomachine and the fuel injection command of the thermal part 2b of the hybridized turbomachine according to a model.

[0105] The torque instruction intended for the electrical part 2a of the hybridized turbomachine is received by a first saturation means 12a before being transmitted to the hybridized turbomachine 2.

[0106] Similarly, the fuel injection command to the thermal part 2b of the hybridized turbomachine is received by a second saturation means 12b before being transmitted to the hybridized turbomachine 2.

[0107] The first saturation means 12a also receives a fault signal from the fault detection means 6 in order to control the activation of the saturation.

[0108] A first saturation subtractor 13a realizes the difference between the command of torque to the electrical part 2a of the turbomachine before and after saturation. A signal is transmitted to the calculation means 11 when the instructions before and after saturation differ.

[0109] In normal operation, the first saturation means 12a is configured so as not to saturate the torque setpoint. However, in the event of a fault in the electrical part 2a of the hybrid turbomachine 2, a difference in rotation speed appears. Indeed, in the event of a fault, the torque setpoints from the calculation means 11 are not produced by the faulty electrical part of the hybrid turbomachine 2, which has a consequence on the torque produced and measured.

[0110] Without corrective action, the calculation means 11 increases the setpoint assigned to the part of the hybrid turbomachine 2 that has failed, without this having any effect on the torque achieved.

[0111] The corrective measures introduced by the present invention are located at the level of the control of the first saturation means 12a triggered by the fault signal received from the fault detection means 6, at the level of the detection of the saturation by the first saturation subtractor 13a and at the level of the taking into account of this saturation by the calculation means 11.

[0112] The saturation carried out by the first saturation means 12a makes it possible to limit the setpoint transmitted to the hybridized turbomachine to a predefined value when a fault has been detected.

[0113] The first saturation subtractor 13a then determines that a difference exists between the torque command transmitted by the calculation means 11 and the torque command transmitted by the first saturation means 12a.

[0114] The first saturation subtractor 13a then transmits a fault signal to the calculation means 11. Upon receipt of this fault signal, the calculation means 11 modifies the distribution of the torque setpoints between the parts of the hybrid turbomachine 2 so as to reduce the contribution of the faulty part of the hybrid turbomachine 2.

[0115] In a particular embodiment, the electrical part 2a of the turbomachine comprises an electrical part connected to a transmission shaft of the low pressure (LP) part of the LP turbomachine and an electrical part connected to a transmission shaft of the high pressure (HP) part of the turbomachine.

[0116] A distinction is made between breakdowns of the LP electrical part and breakdowns of the HP electrical part. To achieve this, the rotation speed of the LP electrical part and the rotation speed of the HP electrical part are measured. The disturbance vector then comprises a disturbance value specific to the LP electrical part and a disturbance value specific to the HP electrical part. It is determined which of these values ​​remained above the predetermined threshold for the predetermined duration. The BP part or the HP part of the machine is associated with a fault depending on the identified value.

[0117] Depending on the identification of the failure of the LP electrical part or the HP electrical part of the turbomachine, the torque compensation is carried out by the other parts of the turbomachine. For example, if the electrical part linked to the low pressure part of the hybridized turbomachine is considered to be faulty, the torque command normally transmitted to the electrical part linked to the low pressure part of the hybridized turbomachine must be carried out totally or in part by the other parts of the hybridized turbomachine 2.

[0118] The rotation speed instructions are determined for the HP electrical part and for the LP electrical part.

[0119] The torque setpoint for the HP electrical part of the turbomachine is determined as a function of the difference between the setpoint and the measurement of rotation speed of the HP transmission shaft received at the input.

[0120] The torque setpoint for the LP electrical part of the turbomachine is determined as a function of the difference between the setpoint and the measurement of the rotation speed of the LP transmission shaft received at the input.

[0121] The torque setpoint for the thermal part of the turbomachine is determined as a function of the difference between the setpoint and the rotation speed measurement received at the input for the LP electrical part and for the HP electrical part.

[0122] The torque setpoint for the HP electrical part and the torque setpoint for the LP electrical part are transmitted to the turbomachine via separate saturation means, each receiving a specific fault signal as a function of the fault identified by the fault detection means 6.

[0123] A second subtractor relating to the HP electrical part and a second subtractor relating to the LP electrical part each determine the difference between the torque command before and after saturation. Each second subtractor transmits a specific deviation signal to the calculation means 11 so that the latter modifies the distribution of the torque realization between the different parts of the hybridized turbomachine.

[0124] In each of the embodiments described above, the failure detection signal can also be used to decouple the electrical part 2a of the turbomachine or more specifically the LP electrical part or the HP electrical part of the hybridized turbomachine.

[0125] In another embodiment, the observer is sized to take into account the disturbances of the thermal part of the hybridized turbomachine.

[0126] The disturbance vector then includes a value relative to the fuel flow rate.

[0127] The measurement vector includes a value relating to the static air pressure in outlet of the high pressure part of the hybrid turbomachine in order to maintain the observability property. The hybrid turbomachine is then equipped with a sensor for measuring the static pressure at the outlet of the high pressure part of the hybrid turbomachine.

[0128] Figure [Fig.3] illustrates the main elements of the control determination means 4, configured to perform the fault adaptation in addition to the determination of the controls of the hybridized turbomachine 2, in another embodiment taking into account the faults on the thermal part of the hybridized turbomachine.

[0129] The elements in common with the figure [Fig.2] are not redescribed.

[0130] In this embodiment, the means 3 for determining the setpoints determines a static air pressure setpoint at the outlet of the high pressure part of the hybridized turbomachine intended for the thermal part of the hybridized turbomachine as a function of external requests.

[0131] The control determination means 4 comprises a subtractor 10b of static air pressure at the outlet of the high pressure part of the hybridized turbomachine, determining the difference between the static air pressure regulation setpoint at the outlet of the high pressure part of the hybridized turbomachine and the static air pressure measurement at the outlet of the high pressure part of the corresponding hybridized turbomachine.

[0132] The static air pressure difference at the outlet of the high pressure part of the hybridized turbomachine determined by the fuel pressure subtractor 10b is transmitted to the calculation means 11 configured to determine the torque commands of the electrical part 2a of the hybridized turbomachine and the fuel injection command of the thermal part 2b of the hybridized turbomachine according to a model.

[0133] The second saturation means 12b is connected to the fault detection means 6 and can receive a fault signal in order to control the activation of the saturation.

[0134] The command determination means 4 comprises a second saturation subtractor 13b, configured to produce the difference between the fuel injection command to the thermal part 2b of the turbomachine before and after saturation by the second saturation means 12b.

[0135] In this mode of operation, the adaptation and accommodation of failure relating to the thermal part of the hybridized turbomachine is carried out in a similar manner to the adaptation and accommodation of failure relating to the electrical part of the hybridized turbomachine.

[0136] In normal operation, the second saturation means 12b is configured so as not to saturate the fuel injection setpoint. However, in the event of a fault on the thermal part 2b of the hybrid turbomachine 2, a difference in fuel pressure appears. Indeed, in the event of a fault, the fuel injection instructions from the calculation means 11 are not carried out by the thermal part of the faulty hybrid turbomachine 2.

[0137] Without corrective action, the calculation means 11 increases the setpoint assigned to the part of the hybrid turbomachine 2 that has failed, without this having any effect.

[0138] The corrective measures introduced are at the level of the control of the second saturation means 12b triggered by the fault signal received from the fault detection means 6, at the level of the detection of the saturation by the second saturation subtractor 13b and at the level of the taking into account of this saturation by the calculation means 11.

[0139] The saturation carried out by the second saturation means 12b makes it possible to limit the setpoint transmitted to the hybridized turbomachine to a predefined value when a fault has been detected.

[0140] The second saturation subtractor 13b then determines that a difference exists between the fuel injection command transmitted by the calculation means 11 and the fuel injection command transmitted by the second saturation means 12b.

[0141] The second saturation subtractor 13b then transmits a fault signal to the calculation means 11. Upon receipt of this fault signal, the calculation means 11 modifies the distribution of the torque setpoints between the parts of the hybrid turbomachine 2 so as to reduce the contribution of the faulty part of the hybrid turbomachine 2.

[0142] Figure [Fig.4] illustrates an example of fault detection and accommodation of an HP electric machine without torque measurement comprising different stages of setting up fault detection and accommodation in the absence of measurement through four graphs.

[0143] In this figure, the first graph illustrates the evolution of the rotation speed NH_rpm_est of the estimated high pressure shaft, the evolution of the rotation speed NH_rpm_mes of the measured high pressure shaft and the evolution of the rotation speed setpoint NH_dmd of the high pressure shaft as a function of time.

[0144] The second graph illustrates the evolution of the estimated disturbance Pert_TRQ_HP_est of unmeasured HP torque in the evolution of the detection threshold TRQ_HP_failure_THR_max of disturbance (in the direction of a torque injection on the HP shaft), and the evolution of the detection threshold TRQ_HP_failure_THR_min of disturbance (in the direction of a torque extraction on the HP shaft) over time.

[0145] The third graph illustrates the evolution of the torque control Final TRQ_HP_cmd_sat sent by the hybrid turbomachine regulation, the evolution of the maximum saturation TRQ_HP_cmd_max of the torque sent by the hybrid turbomachine regulation and the evolution of the minimum saturation TRQ_HP_cmd_min of the torque sent by the hybrid turbomachine regulation, as a function of time.

[0146] The fourth graph illustrates the evolution of the TRQ_HP_failure detection status of HP electrical machine failure as a function of time, the value 0 indicating the absence of failure, the value 1 indicating the presence of a failure.

[0147] Note that the four graphs are synchronized in time.

[0148] At t=tl, a torque setpoint of ONm is transmitted. An offset of 3Nm appears on the torque applied by the HP electric machine. The calculation means 11 reconstructs the disturbance via the observer.

[0149] At t=t2, the deviation value has remained above the predetermined threshold for the predetermined duration (second graph), a fault signal is then emitted (fourth graph). The fault accommodation actions are implemented by modifying the setpoint and adapting the saturation of the electrical machines (third graph).

[0150] At t=t3, the disturbance disappears (second graph). The disturbance estimated by the calculation means 11 through the observer converges towards 0.

[0151] At t=t4, the deviation value has remained below the predetermined threshold for the predetermined duration, the emission of the fault signal is stopped (fourth graph). The fault accommodation actions are withdrawn by restoring the unmodified setpoint and by restoring the prior saturation of the electrical machines (third graph).

Claims

Claims

1. Control system for a hybrid turbomachine (2) comprising at least one electrical part (2a) and one thermal part (2b) and at least one transmission shaft connected to at least one of the electrical (2a) and thermal (2b) parts, said hybrid turbomachine (2) being provided with at least one sensor for measuring the rotational speed of said at least one transmission shaft, the control system comprising a means (3) for determining at least one rotational speed setpoint as a function of at least one request and being characterized by the fact that it comprises: a. a means of observation (5) of the hybridized turbomachine (2) by means of observer modeling configured to determine a disturbance vector of a command, b. a fault detection means (6) configured to emit a fault signal when at least one of the values ​​of the disturbance vector is greater than a predetermined threshold, and c. a means of determining (4) orders comprising: • a means of calculating (11) the torque commands to the hybrid turbomachine (2) as a function of the setpoint and the measurement of rotation speed and a fault signal, • a first means of saturation (12a) of the torque control intended for the electrical part (2a) of the hybridized turbomachine, the first means of saturation (12a) also receiving the failure signal, • a saturation subtractor (13a) configured to produce the difference between the torque command to the electrical part (2a) of the turbomachine before and after saturation by the first saturation means (12a), and to emit the fault signal in the event of a difference.

2. Control system according to claim 1, in which the means (4) for determining commands comprises a subtractor (10a) of rotation speeds, determining the difference between the re-

3. rotational speed control of the hybridized turbomachine and the corresponding rotational speed measurement, the calculation means (11) then being configured to determine the torque control of the electrical part (2a) of the hybridized turbomachine and a fuel injection control of the thermal part (2b) of the hybridized turbomachine as a function of a model and the rotational speed difference determined by the rotational speed subtractor (10a). Control system according to claim 1 or 2, wherein the turbomachine (2) comprises a low pressure (LP) part provided with a rotational speed sensor of the LP part and a high pressure (HP) part being provided with a rotational speed sensor of the HP part, the electrical part (2a) of the turbomachine (2) comprising an independent LP electrical part and an HP electrical part, and wherein: • the means (3) for determining rotation speed instructions determines the rotation speed instructions for the HP electrical part and the LP electrical part based on at least one request, • the command determination means (4) comprises a BP rotation speed subtractor determining a BP deviation signal as a function of the deviation between the rotation speed of the BP part and the rotation speed command of the BP part, and an HP rotation speed subtractor determining an HP deviation signal as a function of the deviation between the rotation speed of the HP part and the rotation speed command of the HP part, • the calculation means (11) determines an HP torque setpoint for the HP electrical part of the turbomachine as a function of the HP deviation signal, an BP torque setpoint for the BP electrical part of the turbomachine as a function of the BP deviation signal, and a fuel injection command for the thermal part of the turbomachine as a function of the BP deviation signal and the HP deviation signal, • the fault detection means (6) as a function of the control disturbance vector received from the observation means (5) is configured to emit a fault signal specific to the LP electrical part or to the HP electrical part of the turbine

4. hybridized bomachine when the corresponding value of the disturbance vector is greater than the predetermined threshold, • the means for determining (4) commands comprising a means for saturating the torque control of the BP electrical part and a means for saturating the torque control of the HP electrical part, the means for saturating the torque control of the BP electrical part receiving the fault signal of the BP electrical part, the means for saturating the torque control of the HP electrical part receiving the fault signal of the HP electrical part, • the means for determining (4) commands also comprising a BP saturation subtractor emitting a fault signal when the values ​​of the torque command of the BP electrical part before and after saturation differ, and an HP saturation subtractor emitting a fault signal when the values ​​of the torque command of the HP electrical part before and after saturation differ, • the calculation means (11) receiving the fault signals from the BP saturation subtractor and the HP saturation subtractor so as to modify, depending on the identified fault, the distribution between the BP deviation signal and the HP deviation signal with a view to determining the torque setpoints and the fuel injection control. Control system according to claim 3, in which the turbomachine (2) is provided with a sensor for measuring the static pressure at the outlet of the high pressure (HP) part of the hybrid turbomachine, and in which: • the means (3) for determining rotation speed setpoints determines the static air pressure setpoints at the outlet of the high pressure part of the hybrid turbomachine intended for the thermal part as a function of at least one request, • the means (4) for determining commands comprises a subtractor of the measurement of the static air pressure at the outlet of the high pressure part of the hybridized turbomachine and of the static air pressure control at the outlet of the part high pressure of the hybridized turbomachine, • the calculation means (11) determines a fuel injection setpoint as a function of the static air pressure difference signal at the output of the high pressure part of the hybridized turbomachine, • the failure detection means (6) as a function of the disturbance vector of the controls received from the observation means (5) is configured to emit a failure signal specific to the thermal part when the corresponding value of the disturbance vector is greater than the predetermined threshold, • the second saturation means (12b) of the fuel injection control is configured so as to receive the failure signal of the thermal part, • the control determination means (4) also comprising a second fuel injection saturation subtractor (13b) emitting a fault signal when the fuel injection values ​​of the thermal part before and after saturation differ,• the calculation means (11) receiving the fault signal from the second fuel injection saturation subtractor (13b) so as to modify the distribution of the setpoints between the thermal part and the electrical part of the hybridized turbomachine with a view to determining the torque setpoints and the fuel injection control.,

5. A control system according to any one of claims 1 to 4, wherein a fault signal is only issued if the determined disturbance vector value greater than the predetermined threshold remains greater than said predetermined threshold for a predetermined duration.

6. Control system according to any one of claims 3 to 5, wherein the fault detection signal is transmitted to the hybridized turbomachine (2) so as to decouple the electrical part (2a) of the hybridized turbomachine, the LP electrical part or the HP electrical part of the hybridized turbomachine.

7. Control system according to any one of claims 1 to 6, in which the means (4) for determining commands comprises a second means (12b) for saturating the injection command of fuel for the thermal part (2b) of the hybrid turbomachine.

8. Method for controlling a hybrid turbomachine (2) comprising at least one electrical part (2a) and one thermal part (2b) and at least one transmission shaft connected to at least one of the electrical (2a) and thermal (2b) parts, said hybrid turbomachine (2) being provided with at least one rotation speed measuring sensor, the control method comprising the following steps: a. determination of at least one rotation speed setpoint based on at least one request b. determination of a control disturbance vector by means of observer modeling of the hybridized turbomachine, c. issuing a fault signal when at least one of the values ​​of the disturbance vector is greater than a predetermined threshold, and d. determination of orders including the following sub-steps: • calculation of torque commands to the hybrid turbomachine (2) based on a rotation speed setpoint, a measurement of the rotation speed of the hybrid turbomachine and a fault signal, • saturation of the torque control to the electrical part (2a) of the hybrid turbomachine, depending on the fault signal, • transmission of a fault signal to the calculation means (11) in the event of a difference between the torque command to the electrical part (2a) of the turbomachine before and after saturation.

9. Aircraft equipped with a hybrid turbomachine (2) and a control system according to any one of claims 1 to 7 or a control means configured to carry out the control method according to claim 8.

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