FR3123051A1 - METHOD AND DEVICE FOR OPTIMIZING THE ELECTRICAL ENERGY OF A HYBRID-MOTORIZED AIRCRAFT - Google Patents

Abstract

Method for optimizing electrical energy available during a flight of an aircraft (100) comprising one or more turbine engines hybridized with one or more reversible electric motors, for which the method comprises in said flight the integration of at least a gliding flight phase (31, 41) with one or more of said turbomachines switched off for which an autorotation of a fan, or low pressure turbine, (1) or of a rotary wing of each of said turbomachines drives said reversible electric motors ( 4) operating as electrical generators and supplying electrical energy (5) during said phase of gliding flight. Figure 3

Description

METHOD AND DEVICE FOR OPTIMIZING THE ELECTRICAL ENERGY OF A HYBRID-MOTORIZED AIRCRAFT

The invention relates to the field of motorization of heavier-than-air aircraft for transporting objects and/or people from an origin to a destination by air. To do this, a heavier-than-air aircraft needs to be equipped with a certain number of engines, the principle of which is to generate the thrust necessary to cause and maintain the lift of the aircraft throughout its flight. use.

At present, the use of electrical energy for the motorization of airplanes or helicopters represents a major challenge in the years to come, with a view to reducing harmful emissions and the consumption of non-renewable sources, in particular fossil fuels. .

Hybrid or electric motorization for aircraft is in particular being studied by all aeronautical companies in the world. The main emerging concepts are based on the addition of an electric motor to provide the mechanical transformation necessary for the propulsion of the device, drawing its necessary electrical energy from on-board storage modules, such as batteries.

These batteries can thus store electrical energy during use of the device to supply energy to the associated electric motor. They must be charged before use and their load capacity is directly dependent on their dimensions.

Technical problem

At present, a major problem is that the storage of electrical energy resources in batteries is too heavy: an electric-type motorization has the major drawback of requiring a very large quantity of batteries, the mass of which is very substantial. In the case of aircraft, mass is a critical factor to consider, as its influence is of the first order on the amount of energy required to carry it through the air. It is for this reason that the elements constituting an aircraft (including engines) are constantly optimized to minimize their mass. Regarding batteries, some studies show that with current technologies, it would take the equivalent in weight of a second aircraft connected to the first to power the engines of the latter, which is not profitable. Transport airplane or helicopter type aircraft therefore remain dependent on the use of thermal engines of the turbomachine type.

However, there are studies of electrically powered aircraft such as in document US20150097079 A1 which provide for battery charging in flight phases where the electric thrusters become wind turbines. In this document, the route that the aircraft can follow depends on the atmospheric/climatic conditions, the altitude regain being done in particular in an ascending column of air when such a column of air is present. It is therefore not suggested in this document to carry out an imposed course by repeatedly linking sequences comprising a glider flight phase (energy recovery) followed by a motorized flight phase for altitude recovery. regardless of the atmospheric conditions on the route of the aircraft. The aircraft described is therefore not really usable for commercial flights.

The document FR3003845A1 describes for its part an aircraft equipped in particular at the tips of the wings with electric generators of the turbine type (known under the English name Ram Air Turbine RAT) which makes it possible to supply electrical energy to supply electrical or electronic equipment of the 'aircraft. However, these generators cannot participate in the generation of the thrust allowing the aircraft to fly.

In view of the prior art and to respond to this problem of insufficient load capacity, the present disclosure proposes an aircraft with hybrid turbomachines associated with a load module in glider mode and a method for optimizing the energy consumption of this aircraft which comprises phases for recovering electrical energy within the hybrid turbomachine of the aircraft and phases for restoring said electrical energy in addition to the thermal energy supplied by the turbomachines.

More specifically, the present invention proposes a method for optimizing the electrical energy available during a flight of an aircraft which comprises one or more turbomachines hybridized with one or more reversible electric motors, the method comprising in said flight the integration of 'at least one gliding flight phase with one or more of said turbomachines switched off for which an autorotation of a fan or of a rotary wing of a said turbomachine drives said reversible electric motor associated with this turbomachine, said reversible electric motor operating in electrical generator and providing electrical energy during said phase of gliding flight.

This makes it possible in particular to charge batteries storing said electrical energy, in particular during the descent phase of the aircraft.

Advantageously, the flight of the aircraft comprising at least a climb phase, a level flight phase and a descent phase, one or more gliding flight phases are integrated into the descent phase.

This makes it possible to reduce the consumption of the aircraft in fuel for supplying the turbomachines, in particular during the descent phase of the aircraft.

Advantageously, the flight of the aircraft comprising at least a climb phase, a level flight phase and a descent phase, one or more gliding flight phases are integrated into the level flight phase. This makes it possible in particular to maintain the charge of the electrical energy storage batteries.

Preferably, the electrical energy accumulated during the gliding flight phase(s) is at least partly stored and used to supply additional power to the turbomachine(s) during flight phases that consume a lot of energy. For example, this makes it possible to provide additional energy during a take-off phase of a subsequent flight.

The electrical energy generated during the phase or phases of gliding flight can in particular be used to compensate for the stoppage of the turbomachine(s) and supply electrical or electronic equipment of the aircraft with the turbomachines stopped.

The invention further relates to an aircraft suitable for implementing the method of the invention and which comprises at least one reversible electric motor connected directly or indirectly to a turbine shaft of a turbomachine and to an energy storage device onboard, the reversible electric motor and the turbomachine constituting a hybridized turbomachine.

The shaft may be a low pressure turbine shaft in a turbojet or a free turbine shaft in a turboshaft or turboprop.

Said reversible electric motor can be positioned directly in continuity with said turbine shaft.

According to an alternative embodiment, said reversible electric motor can be positioned outside the turbomachine and mechanically connected to said turbine shaft.

According to a particularly advantageous embodiment, the electric motor is configured to be able to drive a fan, a propeller or a rotary wing driven by the turbomachine and provide thrust to the aircraft.

Other characteristics, details and advantages of the invention will appear on reading the detailed description below of non-limiting examples of embodiment, and on analyzing the appended drawings, in which:

shows a block diagram of a hybridized turbomachine in a mode of operation where a reversible electric motor supplies mechanical power to the turbomachine;

shows a block diagram of a hybridized turbomachine in a mode of operation where a reversible electric motor receives mechanical power from the turbomachine and transforms it into electrical energy;

shows an example of flight with glide phases;

and show diagrams of a flight including glide phases of the present disclosure.

shows an application diagram to a helicopter.

Claims (10)

Method for optimizing electrical energy available during a flight of an aircraft (100) comprising one or more turbine engines hybridized with one or more reversible electric motors, characterized in that the method comprises in said flight the integration of at least one phase of gliding flight (31, 41) with one or more of said turbomachines switched off for which an autorotation of a low pressure turbine (1) or of a rotary wing of a said turbomachine drives said reversible electric motor ( 4, 64) associated with this turbomachine, said reversible electric motor operating as an electric generator (G) and supplying electrical energy (5) during said gliding flight phase. Optimization method according to claim 1, for which the flight of the aircraft comprising at least a climb phase (10), a level flight phase (20) and a descent phase (30), one or more of gliding flight (31) are integrated into the descent phase. Optimization method according to claim 1 or 2, for which the flight of the aircraft comprising at least a climb phase, a level flight phase and a descent phase, one or more gliding flight phases (41) are integrated into the level flight phase. Optimization method according to any one of the preceding claims, for which the electrical energy (5) accumulated during the phase or phases of gliding flight is at least partly stored (6) and used to provide additional power ( 7) to the turbomachine(s) (2) during highly energy-consuming flight phases. Optimization method according to any one of the preceding claims, for which the electrical energy (5) generated during the phase or phases of gliding flight is used to compensate for the stoppage of the turbomachine or machines and supply electrical equipment or electronics (8) of the aircraft turbine engines stopped. Aircraft suitable for implementing the method of any one of the preceding claims, characterized in that it comprises at least one reversible electric motor (4, 64) connected directly or indirectly to a shaft (3) of the low pressure turbine (1 ) of a turbomachine and to an on-board energy storage device (6), the reversible electric motor and the turbomachine constituting a hybridized turbomachine. Aircraft according to claim 6 wherein said reversible electric motor (4, 64) is positioned directly in continuity with said low pressure turbine shaft. Aircraft according to claim 6 wherein said reversible electric motor (4, 64) is positioned outside the turbine engine and mechanically connected to said low pressure turbine shaft. Aircraft according to claim 6, 7 or 8 for which the electric motor (4, 64) is configured to be able to drive a low pressure turbine, a propeller or a rotary wing (62) driven by the turbomachine and to provide thrust to the aircraft . Aircraft according to any one of claims 6 to 9 for which the electric motor (4, 64) is configured to be able to operate as an electric generator (G) in order to recharge batteries (6) and/or supply electrical or electronic equipment ( 8) of the aircraft (100).