Method for controlling hybrid turbine engine

Abstract

A method for controlling a hybrid turbine engine (11) for an aircraft, said turbine engine (11) comprising a low-pressure shaft rod (10), a high-pressure shaft rod (9), at least one power conversion device (13) mounted on said low-pressure shaft rod (10) or high-pressure shaft rod (9), and an energy storage assembly comprising a plurality of capacitive assemblies (15), the method comprises the steps of:-pre-charging the capacitive component (15) until an average voltage reaches a first partial charge value,-balancing the voltage of the capacitive component (15),-charging the capacitive component (15) until the average voltage reaches a high value,-balancing the voltage of the capacitive component (15) until the average voltage reaches a second partial charge value,-balancing the voltage of the capacitive component (15). And-converting the electrical energy stored in the storage assembly into mechanical energy delivered to the low-pressure shaft lever (10) and / or to the high-pressure shaft lever (9) in order to assist in the maneuvering of the aircraft.

Description

Technical Field

[0001] The field of the invention is that of aviation turbine engines and in particular of aircraft engines produced in the form of twin-shaft turbofans. More specifically, the invention relates to a method for controlling a hybrid turbine engine of an aircraft. Background Art

[0002] Thermal / electric hybridization of aircraft turbine engines offers a new path to improve the behavior and performance of these turbine engines.

[0003] This mixing consists of feeding or extracting mechanical power at a certain time and at a certain level via an electric motor mounted on the rotating shaft of the turbine engine.

[0004] A key requirement of conventional turbine engines for aircraft propulsion is to ensure that the maximum ascent time is not exceeded between the idle speed at which the engine produces only low thrust and the maximum speed at which the engine thrust is at its maximum.

[0005] Figure 1 A conventional twin-shaft turbofan type turbine engine is schematically shown in FIG.

[0006] It generally comprises, from upstream to downstream in the air flow direction, a fan S, a low-pressure compressor 1 , a high-pressure compressor 2 , a combustion chamber 3 receiving a fuel flow Qc, a high-pressure turbine 4 , a low-pressure turbine 5 and a primary exhaust nozzle 6 .

[0007] The low-pressure compressor 1 and the low-pressure turbine 5 are connected via a low-pressure shaft 10 and together form a low-pressure body.

[0008] The high-pressure compressor 2 and the high-pressure turbine 4 are connected via a high-pressure shaft 9 and form a high-pressure body together with the combustion chamber.

[0009] A fan S driven directly or via a reduction gearbox by a low-pressure shaft 10 compresses the air coming from the air inlet. Downstream of the fan S, this air is divided into a secondary air flow, which is directed directly towards a secondary nozzle (not shown) through which it is ejected to contribute to the thrust provided by the turbine engine, and a so-called primary flow, which enters a gas generator consisting of a low-pressure body and a high-pressure body and is then ejected into the primary nozzle 6.

[0010] Conventionally, it is known to install generators in turbine engines in order to power the onboard electrical systems. These generators are driven by the high-voltage shaft 9 via the accessory gearbox in order to convert mechanical energy into electrical energy intended for secondary systems on board the aircraft.

[0011] A variant may consist of replacing at least one of the generators with at least one starter to start the turbine engine using electrical energy. The start-up is achieved by controlling the electric starter via a converter located in the engine area or in the cockpit area, the converter being started by powering it from a source external to the turbine engine. This source may be a ground-based power unit or another onboard power source previously activated (auxiliary power generator, generator of another turbine engine). Once the turbine engine has started, the electric starter changes mode to operate exclusively as a generator.

[0012] However, the use of this system to assist a turbine engine by supplying a large amount of electrical energy is not always satisfactory, since it requires the use of a high-capacity electrical energy source located in the aircraft area and the associated electrical connections, which result in a large volume and high electrical losses. Summary of the invention

[0013] The present invention aims to overcome these drawbacks by providing a method for supplying energy to a turbine engine that allows rapid delivery of large amounts of electrical energy while ensuring good stability and durability of the system.

[0014] To this end, the invention relates to a method for controlling a hybrid turbine engine for an aircraft, the turbine engine comprising a low-pressure body with a low-pressure shaft and a high-pressure body with a high-pressure shaft, the turbine engine also comprising at least one power conversion device mounted on the low-pressure shaft or the high-pressure shaft and an energy storage assembly connected to the power conversion device, the energy storage assembly comprising a plurality of capacitor assemblies,

[0015] The method comprises the following steps:

[0016] - pre-charging the capacitive component until the average voltage across the capacitive component reaches the first partial charge value,

[0017] - balancing the voltage across each of the capacitive components,

[0018] - rapidly charging the capacitive component until the average voltage across the capacitive component reaches a high value, and

[0019] -Converting electrical energy stored in the storage assembly into mechanical energy that is delivered to the low pressure shaft and / or the high pressure shaft in order to assist in maneuvering the aircraft.

[0020] This approach allows to optimize the operation of the capacitive assembly by using the maximum amount of stored energy without degrading its service life.

[0021] In practice, wear in the capacitor assemblies is mainly associated with the temperature, which in our case depends on the environment and is difficult to control, and with the voltage maintained at the terminals of the capacitor assemblies. In order to maximize the use of their energy to assist the turbine engine, the capacitor assemblies are charged to their maximum voltage value (typically 2.85V) just before the flight phase requiring assistance.

[0022] The first partial charge value and the second partial charge value are selected so that the capacitive component can be maintained at these voltage values ​​without accelerated aging or significant damage.

[0023] The high voltage value is substantially equal to the maximum charging voltage of the capacitor component.

[0024] The pre-charging step may be performed while the aircraft is stationary on the ground.

[0025] A balancing step may be performed while the aircraft is traveling on the ground to a take-off position.

[0026] The rapid charging procedure may be performed while the aircraft is stopped for pre-takeoff checks.

[0027] The aircraft maneuver may be take-off.

[0028] Alternatively, the maneuver may correspond to any other flight phase requiring acceleration of the turbine engine shaft or a rapid increase in the speed of the turbine engine shaft.

[0029] This feature makes it possible to provide additional energy for the propulsion of the aircraft at the most critical moment of its acceleration.

[0030] The method may further comprise the step of using the electrical energy stored in the capacitive assembly to power a load of the aircraft during flight.

[0031] This feature makes it possible to improve the operation of the secondary circuit of the machine during flight phases when assistance to the turbine engine is not required.

[0032] A power conversion device may be mounted on the high-pressure shaft and arranged to transfer power only between the high-pressure shaft and the energy storage assembly, the turbine engine also comprising a second power conversion device mounted on the low-pressure shaft and arranged to draw power from the low-pressure shaft to power the aircraft's loads during flight.

[0033] This feature allows reducing the weight and costs of the power conversion device associated with the high-voltage shaft, which is only responsible for the load of the energy storage assembly.

[0034] This power supply via the low-voltage shaft is compatible with improving the quality of the electrical network by means of the energy stored in the capacitive assembly.

[0035] The method may further comprise the following steps:

[0036] - recharging the capacitive component until the average voltage across the capacitive component reaches a second partial charge value,

[0037] - charging the capacitive component until the average voltage across the capacitive component reaches a high value, and

[0038] - making available, during a second maneuver of the aircraft, the electrical energy stored in the capacitive assembly in order to assist a possible secondary maneuver, and

[0039] If no auxiliary maneuver is carried out, the capacitive component is discharged.

[0040] This feature makes it possible to assist possible auxiliary maneuvers that require acceleration assistance.

[0041] The second maneuver of the aircraft may be a landing, and the secondary maneuver may be an emergency takeoff (touch-and-go, go-around, etc.).

[0042] This feature makes it possible to assist emergency maneuvers when the aircraft is landing, thus improving the safety of the landing.

[0043] The energy storage assembly may be configured to deliver greater than or equal to 500 kW of electrical power for a duration between 0.5 seconds and 2 seconds.

[0044] This feature makes it possible, for example, to concentrate the auxiliary power at critical moments during the take-off phase.

[0045] The balancing step may be implemented by means of a balancing circuit configured to reduce the voltage across each capacitive component to a threshold voltage after the pre-charging step.

[0046] This feature makes it possible to avoid damage to individual capacitive components due to uneven voltages in the energy storage assembly.

[0047] This balancing circuit is activated, for example, at the beginning of a balancing step and is deactivated after this balancing step in order to implement a fast charging step.

[0048] The threshold voltage may be modified during implementation of the method.

[0049] This feature allows the partial charging voltage to be modified according to the different requirements associated with different flight phases.

[0050] The length of time separating the step of charging the capacitive component and the step of converting the stored electrical energy may be less than or equal to 10 minutes.

[0051] This feature allows limiting how long the capacitive components remain at a high charging voltage and therefore allows reducing their aging. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is a schematic representation of a twin-shaft turbine engine according to the state of the art,

[0053] Figure 2 is a schematic representation of a turbine engine for implementing the method according to the invention,

[0054] Figure 3 yes Figure 2 Electrical diagram of the energy storage assembly of a turbine engine,

[0055] Figure 4 yes Figure 2 Electrical diagram of a portion of the balancing circuit of a turbine engine,

[0056] Figures 5 to 8 Schematic representation of the control Figure 2 A method for a turbine engine,

[0057] Fig. 9 and 10 Schematically showing a method for controlling a hybrid turbine engine according to a second embodiment of the invention,

[0058] Fig.11 and 12 A method for controlling a hybrid turbine engine according to a third embodiment of the invention is schematically represented. DETAILED DESCRIPTION

[0059] Figure 2 A turbine engine 11 is shown mounted on an aircraft and capable of implementing the method according to the invention. Figure 1 The turbine engine 11 of the turbine engine includes, from upstream to downstream in the direction of airflow, a fan S, a low-pressure compressor 1, a high-pressure compressor 2, a combustion chamber 3 receiving a fuel flow Qc, a high-pressure turbine 4, a low-pressure turbine 5 and a primary exhaust nozzle 6.

[0060] The low-pressure compressor 1 and the low-pressure turbine 5 are connected via a low-pressure shaft 10 and together form a low-pressure body.

[0061] The high-pressure compressor 2 and the high-pressure turbine 4 are connected via a high-pressure shaft 9 and form a high-pressure body together with the combustion chamber 3 .

[0062] A fan S driven directly or via a reduction gearbox by a low-pressure shaft 10 compresses the air coming from the air inlet. Downstream of the fan S, this air is divided into a secondary air flow, which is directed directly towards a secondary nozzle (not shown) through which it is ejected to contribute to the thrust provided by the turbine engine, and a so-called primary flow, which enters a gas generator consisting of a low-pressure body and a high-pressure body and is then ejected into the primary nozzle 6.

[0063] The turbine engine 11 further comprises a power conversion device 13 coupled to the high-pressure shaft 9 . The power conversion device 13 is capable of converting electrical power into mechanical power causing the rotation of the high-pressure shaft 9 .

[0064] The power conversion device 13 is in particular able to operate alternately as a motor and as a generator, depending on the flight phase of the aircraft, and to take mechanical power from the high-voltage shaft 9 to convert it into electrical power.

[0065] The power conversion device 13 is connected to the high-pressure shaft 9 , for example via an accessory gearbox (not shown) engaged with the high-pressure shaft 9 .

[0066] The turbine engine 11 also includes an electrical energy storage assembly comprising a power converter 14 and a plurality of capacitor assemblies 15 .

[0067] The capacitor component 15 is specifically a supercapacitor, such as a carbon nanotube supercapacitor.

[0068] A typical order of magnitude for start-up assistance of a turbine engine is supplying about 500 kW of power for a duration of about 1 s, so the total energy supplied is about 500 kJ. In this case, the capacity design of a supercapacitor-based storage assembly is defined by both the power density of the capacitive component and the energy density of its storage.

[0069] In this regard, supercapacitors made with carbon nanotubes and graphene make it possible to increase the conductivity and therefore divide the resistivity of the component by 10 (or more), which allows the storage system to be suitable for operating cycles of about one second (rather than 10 to 20 seconds for conventional supercapacitors).

[0070] The storage assembly comprises, for example, 296 carbon nanotube supercapacitors of 900 F capacitance connected in series, which makes it possible to obtain an equivalent series resistance (ESR) of less than 100 μOhm per assembly.

[0071] This number of supercapacitors with this capacitance allows the energy storage assembly to store and recover sufficient electrical power to meet the needs mentioned above.

[0072] However, maintaining these supercapacitors at charge levels close to their maximum charge for extended periods of time may damage the capacitors over time, thereby shortening the length of time that the energy storage assembly can operate normally.

[0073] Energy storage components Figure 3 It is schematically shown in Figure 3 The electrical architecture of the assembly is shown. The conversion device 13 conventionally comprises an electric machine 13a and an inverter 16, the latter being connected in parallel to a power converter 14, here a DC / DC converter of the chopper type.

[0074] The inverter 16 and the converter 14 are configured to control the power drawn from or fed to the high voltage shaft 9 or delivered to the load 12 .

[0075] The energy storage assembly is, for example, also connected in parallel to the loads 12 of the aircraft and can be used to supply them with electrical energy.

[0076] The energy storage assembly further includes a balancing circuit 20 which is provided in part at Figure 4 , is configured for balancing the voltage across the capacitive components 15 by dissipating excess stored energy, so that each capacitive component 15 has a voltage at its terminals substantially equal to an average voltage that depends on the total energy stored by the system after the excess energy is dissipated.

[0077] Alternatively, balancing circuit 20 may be configured to transfer energy between capacitive components 15 in order to balance the voltage across the capacitive components.

[0078] In practice, after a first phase of precharging the capacitive components, the charge of the individual capacitive components may vary from one component to another, in particular due to variations in the individual capacitances of the components or due to spontaneous partial discharges.

[0079] However, wear and premature aging of a capacitor component is directly related to the voltage at its terminals and generally results in a reduction in the capacitance of the component. Since reduced capacitance results in a higher voltage at the terminals of the component under equal load, it should be understood that any overvoltage has an effect that tends to be amplified and results in accelerated degradation of the component.

[0080] Thus, the use of the balancing circuit 20 allows the capacitive components 15 to be protected by applying a uniform voltage across the various capacitive components 15 .

[0081] The balancing circuit 20 and the storage assembly define a plurality of cells 21, each cell comprising a capacitive assembly 15. Each cell 21 is self-powered and measures the voltage at the terminals of the capacitive assembly 15.

[0082] The balancing circuit 20 comprises an isolated control voltage terminal Set, which allows activating the control of the balancing circuit 20 and centrally managing the entire balancing circuit 20 .

[0083] Activation of this control triggers a balancing cycle, described below.

[0084] If the voltage measured across the capacitive component 15 is greater than a threshold value 22 (2.3 V in this example), the comparator 23 switches the switching transistor 24 and the capacitive component 15 is discharged into the resistor 25 with a time constant RC of several minutes. Once the voltage across the capacitive component 15 is less than or equal to the threshold value 22, the transistor 24 is no longer conducting and the capacitive component 15 stops discharging.

[0085] The value of the threshold 22 is, for example, set equal to a so-called intermediate charge value at which the capacitive component 15 does not suffer damage or excessive aging.

[0086] Advantageously, the value of threshold 22 may be modified dynamically during different flight phases of the aircraft.

[0087] Thus, at the end of each balancing cycle, all capacitive components 15 having an initial voltage greater than the threshold 22 are discharged to said threshold. Thus, in operating phases where the capacitive components are loaded to values ​​above the threshold, it is sufficient to deactivate the control Set so that the balancing circuit 20 is no longer used.

[0088] References below Figures 5 to 8 A method is described for implementing the energy storage assembly described above during flight of an aircraft in which the storage assembly is installed.

[0089] exist Figures 5 to 8 , the flow of electrical energy is schematically represented by arrows between the high pressure body HP and the storage assembly STORE, schematically represented in the turbine engine zone ZT, and the rest of the aircraft AC, including onboard loads and energy sources, represented in the aircraft zone ZA.

[0090] This approach allows the operation of the capacitive assembly 15 to be optimized by using a maximum amount of stored energy without degrading its useful life.

[0091] The method comprises a first step of precharging the capacitor assembly 15, such as Figure 5 As shown, during this period, electrical power is supplied to the capacitive component 15 so that the average voltage across the capacitive component reaches a so-called first partial charge value.

[0092] At the end of the precharging step, the average voltage across the capacitive component 15 is, for example, between 75% and 85% of the maximum charge voltage of said component.

[0093] For example, for an ultracapacitor having a maximum charge voltage substantially equal to 2.85V, the first partial charge voltage is substantially equal to 2.35V.

[0094] The first partial charge voltage is selected such that the capacitive assembly experiences reduced wear when the voltage at the terminals of the capacitive assembly 15 is maintained at the first partial charge voltage relative to the maximum charge voltage.

[0095] The pre-charging step is carried out, for example, when the aircraft is parked. It can last for several minutes, which makes it possible to use a reduced charging current.

[0096] The energy required to precharge the capacitive assembly comes, for example, from a source located in the aircraft zone, such as an auxiliary power source (or APU, standing for Auxiliary Power Unit) or a ground source outside the aircraft. In fact, at this stage of flight, the turbine engine cannot yet operate as a generator.

[0097] The method then includes balancing the voltage across each of the capacitive components 15, thereby implementing the steps of balancing the system described above.

[0098] The voltages across the various capacitive components 15 are balanced such that each of the capacitive components has a voltage across its terminals that is substantially equal to the predetermined threshold 22, ie substantially equal to the first partial charge voltage.

[0099] This step is carried out, for example, when the aircraft is moved from its parking point on the ground to the take-off position and can last several minutes.

[0100] Then, the method comprises the step of rapidly charging the capacitor assembly 15, such as Figure 6 As shown, until the average voltage across the capacitive component reaches a high value.

[0101] The energy used to charge the capacitive component is drawn from the operating engine via the power conversion device 13 .

[0102] The high value is, for example, between 95% and 100% of the maximum charging voltage of the capacitive component.

[0103] For a total voltage of 843 V, the high voltage of each supercapacitor is, for example, on average approximately equal to 2.85 V. A current of approximately 10 A makes it possible to rise from a partial charge value to a maximum charge value in approximately one minute.

[0104] For example, after the engine has been started, during the minutes required for pre-takeoff checks, a step of rapidly charging the capacitive assembly is performed. The balancing circuit is previously deactivated in order to allow the capacitive assembly to be charged.

[0105] Having the capacitive components 15 at maximum charge just before take-off makes it possible to benefit from maximum assistance in take-off without having to keep these components at maximum charge level for a long time.

[0106] During the fast charging step, the aircraft engines are turned on and operate as generators. It is therefore they that provide the energy for charging the capacitive assembly 15 to its maximum charge via the power conversion device 13.

[0107] The method then includes the step of converting the electrical energy stored in the storage assembly into mechanical energy delivered to the high voltage shaft to assist in the takeoff of the aircraft, such as Figure 7 shown.

[0108] The stored energy is supplied for a duration of approximately 1.5 s, which makes it possible to focus this assistance on the critical moments when maximum acceleration is required.

[0109] This switching causes a partial or complete discharge of the capacitive element 15 .

[0110] Advantageously, the time separating rapid charging of the capacitive assembly until a high voltage is reached and discharging by converting the stored electrical energy into mechanical energy for assisting take-off is less than or equal to 10 minutes, and preferably less than or equal to 5 minutes.

[0111] The method may comprise the subsequent step of recharging the capacitor assembly by using the turbine engine as a generator and by drawing power from the high voltage shaft 9 via the conversion means 13, Figure 6 Same as shown in .

[0112] The capacitive component 15 is recharged until the average voltage across the capacitive component is substantially equal to the second partial charge value.

[0113] The second partial charge value may be equal to the first partial charge value or slightly different while remaining within the same voltage range and having the features and advantages described above.

[0114] For example, for a supercapacitor having a maximum voltage substantially equal to 2.85 V, the second partial charge voltage is substantially equal to 2.2 V, which avoids wear of the supercapacitor.

[0115] Thus, the total voltage across the energy storage assembly is, for example, substantially equal to 650V.

[0116] Once the capacitors are charged, recharging stops and the energy drawn from the high voltage shaft is used only to power the aircraft loads. In the case of load shedding, if the consumption of the loads temporarily becomes too low compared to the power being drawn, the excess power is temporarily stored in the storage system in order to limit overvoltages while adjusting the power being drawn.

[0117] Advantageously, during flight, the energy storage assembly is used to improve the quality of the electrical system of the aircraft by supplementing the energy drawn in a standard manner from the high-voltage shaft 9, such as Figure 8 shown.

[0118] The energy stored in the energy storage assembly is used to power the aircraft's loads 12 exclusively to compensate for individual events of temporary failures and / or excessive demand in the main power supply. When this additional energy is provided, the recharging of the capacitive components is temporarily stopped.

[0119] This step can be done with Figure 6 The recharging of the capacitive assembly 15 shown is carried out alternately, since the additional energy provided in this way is infrequent and exclusive.

[0120] In practice, the storage assembly and the power converter 14 are dimensioned to provide very high power (500 kW in the example described) for a duration of about one second. They can therefore easily assist the generator and its regulation in the event of transient high current draws, short circuits or load shedding in the network, and thus avoid voltage dips and overvoltages on the electrical network of the aircraft.

[0121] The method may then include the step of charging the capacitive component to a maximum value, performed during descent of the aircraft, during which the voltage across the capacitive component rises to an average voltage substantially equal to the maximum charge voltage.

[0122] At the end of the aircraft's descent, during the landing phase, this charge remains available to assist in possible emergency maneuvers such as emergency takeoffs (follow-on takeoff, abandoned landing go-around, etc.).

[0123] After landing, the method comprises a step of discharging the capacitive components 15 in order to protect these components. During the phase of travel of the aircraft on the ground to its parking position, the stored energy can be advantageously used in order to save energy from other sources.

[0124] According to a variant (not shown), the conversion means 13 are configured to operate with alternating current (AC) distributed to the aircraft loads 12. The conversion means 13 are thus, for example, a three-phase generator.

[0125] The converter 14 is then replaced by an AC / DC converter at the input to the electrical energy storage assembly, which allows regulating the input voltage to the DC network composed of the storage assembly. Said converter 14 comprises, for example, a filter of the LC or LCL type.

[0126] According to another embodiment, Fig. 9 and 10As shown, the turbine engine 11 comprises first conversion means 13 associated with the high-pressure shaft 9 in the high-pressure body HP, and second conversion means associated with the low-pressure shaft 10 in the low-pressure body LP, both connected to an energy storage assembly STORE in the turbine engine zone ZT.

[0127] This arrangement provides additional options for methods for controlling the turbine engine 11 and the energy storage assembly.

[0128] In this configuration, the first conversion device 13 is generally not designed to supply power to the load 12, but only to charge the energy storage assembly and assist in acceleration. This design is limited to specialized use, allowing the mass of the device to be reduced.

[0129] In this embodiment, the pre-charging step, the voltage balancing step and the step of charging the capacitor assembly 15 to the maximum voltage remain substantially unchanged. The energy storage assembly is charged by an external source, since the turbine engine cannot operate as an energy generator before take-off.

[0130] The take-off assist also remains unchanged, wherein the stored electrical power is converted by the first conversion device 13 into mechanical power which is supplied to the high-voltage body HP, such as Fig. 9 shown.

[0131] During the flight, if Fig.10 As shown, the electrical power supply to the loads 12 of the aircraft is ensured by the low-voltage body LP, whereas the recharging of the storage assembly STORE is assigned to the high-voltage body HP.

[0132] Thus, when the turbine engine 11 operates as a generator, the first conversion means 13 charge the capacitive components 15 and maintain them at a desired charge level, as explained above, while the second conversion means supply power to the load 12 .

[0133] When acceleration assistance is required, the energy stored in the storage assembly is transferred back to the high-voltage shaft 9 via the first conversion means 13, while the second conversion means continue to supply power to the load 12 without affecting the stress on the high-voltage shaft 9 and without deceleration.

[0134] At the end of this assistance, the body HP resumes its recharging of the storage assembly STORE until landing and resumes performing the final discharge of the capacitive component.

[0135] In the case of covering all DC type networks Fig.11 and 12 In another embodiment shown, two power conversion devices can be arranged electrically in parallel, with a high voltage body HP and a low voltage body LP connected in parallel to supply the loads of the aircraft AC and the storage assembly STORE.

[0136] The pre-charge, balancing, maximum charge and take-off assist steps remain substantially unchanged compared to those described in the previous embodiments.

[0137] After takeoff, when the turbine engine is able to operate in generator mode, the high-pressure HP and low-pressure LP assembly supplies the aircraft AC loads in parallel, such as Fig.11 Furthermore, depending on the requirements, the storage assembly STORE is recharged in parallel by the high voltage HP and low voltage LP assemblies, or exclusively supplies the loads of the aircraft AC in order to stabilize the network.

[0138] In cases where advancement assistance is required, e.g. Fig.12 As shown, the low voltage assembly LP continues to power the loads of the aircraft AC, supplying additional power from the energy storage assembly as necessary. As described above, the assembly HP benefits from the surplus energy stored in the storage assembly.

[0139] The network stabilizing role is therefore maintained for the energy storage assembly STORE in this embodiment, and an overload of the low-voltage assembly LP and the associated slowdown are avoided due to this additional power supply when the assembly HP switches to electric assist mode.

Claims

1. A method for controlling a hybrid turbine engine (11) for an aircraft, the turbine engine (11) comprising a low-pressure body with a low-pressure shaft (10) and a high-pressure body with a high-pressure shaft (9), the turbine engine (11) further comprising at least one power conversion device (13) mounted on the low-pressure shaft (10) or the high-pressure shaft (9) and an energy storage assembly connected to the power conversion device (13), the energy storage assembly comprising a plurality of capacitor assemblies (15), The method comprises the following steps: - pre-charging the capacitive component (15) until the average voltage across the capacitive component (15) reaches a first partial charge value, - balancing the voltage across each of said capacitive components (15), - rapidly charging the capacitive component (15) until the average voltage across the capacitive component (15) reaches a high value, and - Converting the electrical energy stored in the storage assembly into mechanical energy delivered to the low-pressure shaft (10) and / or the high-pressure shaft (9) in order to assist in maneuvering the aircraft.

2. The method according to the preceding claim, characterized in that The maneuver of the aircraft is take-off.

3. The method according to any of the preceding claims, further comprising the step of using the electrical energy stored in the capacitive assembly (15) to improve the quality of service of the electrical network of the aircraft during flight.

4. The method according to any one of claims 1 to 3, characterized in that The power conversion device (13) is mounted on the high-pressure shaft (9) and is arranged to transfer electricity only between the high-pressure shaft (9) and the energy storage assembly, and the turbine engine (11) also includes a second power conversion device, which is mounted on the low-pressure shaft (10) and is arranged to draw electricity from the low-pressure shaft (10) in order to power the aircraft's load (12) during flight.

5. The method according to any one of the preceding claims, characterized in that The method further comprises the following steps: - recharging the capacitive component (15) until the average voltage across the capacitive component (15) reaches a second partial charge value, - charging the capacitive component (15) until the average voltage across the capacitive component reaches the high value, and - making available, during a second maneuver of the aircraft, the electrical energy stored in the capacitive assembly (15) in order to assist a possible secondary maneuver, and If the auxiliary maneuver is not carried out, the capacitive component (15) is discharged.

6. Method according to the preceding claim, characterized in that The second maneuver of the aircraft is a landing, and the secondary maneuver is an emergency takeoff.

7. The method according to any one of the preceding claims, characterized in that The energy storage assembly is configured to deliver greater than or equal to 500 kW of electrical power for a duration between 0.5 seconds and 2 seconds.

8. The method according to any one of the preceding claims, characterized in that The balancing step is implemented by means of a balancing circuit (20) configured to reduce the voltage across each capacitive component (15) to a threshold voltage (22) after the pre-charging step.

9. The method according to the preceding claim, characterized in that The threshold voltage (22) can be modified during implementation of the method.

10. The method according to any one of the preceding claims, characterized in that The time length separating the step of rapidly charging the capacitor component (15) and the step of converting the stored electrical energy is less than or equal to 10 minutes.

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