In-flight charging control device for hybrid aircraft

Abstract

In-flight charging control device for hybrid aircraft An in-flight charging control device for hybrid aircraft comprising at least one electrical generation source and at least two stored electrical energy sources each associated with at least one electrical switch, comprising a matcher (500) arranged to receive a state indicator of each electrical generation source as well as a state indicator of each stored electrical energy source, to determine one or more load groups each associating an electrical generation source with two stored electrical energy sources, and to transmit each load group to a respective supervisor (510,51n), each supervisor (510,51n) being arranged to implement a state machine, to retrieve input data, to determine a new current state of the state machine from the input data,as well as a direct current setpoint for each stored electrical energy source of its load group, and to transmit the new current state of the state machine and the direct current setpoints to a load parameter calculator (520) arranged to determine, for each stored electrical energy source, a direct voltage setpoint, a direct current to direct voltage transition setpoint, a load stop indicator and a forced load indicator from the current state of the state machine and the direct current setpoints of each supervisor as well as an opening or closing setpoint for the electrical switches associated with the stored energy sources to allow electrical grouping thereof. Fig.5,

Description

Title of the invention: In-flight charging control device for hybrid aircraft

[0001] The invention relates to the field of aircraft and more particularly to the field of aircraft with hybrid electric engines.

[0002] The electrification of aviation is one of the major challenges of the early 21st century. This electrification currently relies on two types of solutions: fully electric solutions and hybrid solutions.

[0003] In the first type of solutions, the energy source is based exclusively on batteries, which must therefore be recharged between two flights. In the second type of solutions, developed by the Applicant, sources of stored electrical energy (typically batteries) coexist with sources of electrical generation (typically turbines or fuel cells, or other).

[0004] In this second case, it becomes possible to imagine scenarios in which the electrical generation sources are used to recharge one or more sources of stored electrical energy in flight.

[0005] These scenarios nevertheless represent significant challenges. Indeed, in the field of aviation, it is crucial not to create a "Single point of failure" (or SPOF) for obvious safety reasons.

[0006] It is therefore necessary both to have several sources of stored electrical energy to continue to ensure a supply of electrical energy if one of the sources of stored electrical energy fails but also to isolate them from each other to avoid any propagation of failure, and therefore the creation of SPOFs.

[0007] This isolation is not without consequences, and it leads to a risk of creating significant voltage differences between the stored electrical energy sources. Indeed, the electrical characteristics of the circuits of the latter may be slightly different, and therefore generate a different discharge for each stored electrical energy source. This different discharge results in a different state of charge and therefore a different voltage for each stored electrical energy source, since the voltage depends on the state of charge of the stored electrical energy source.

[0008] It is therefore not possible to charge several sources of stored electrical energy simultaneously by placing them in parallel, since the voltage differences would generate deleterious discharge / recharge behaviors of one source of stored electrical energy in the other.

[0009] A solution for recharging stored electrical energy sources in flight could consist of charging each stored electrical energy source individually. This approach would generate a long recharge time and sub-optimization of the entire system, as the electricity generation sources could then be underutilized.

[0010] To date, the problem is such that, to the Applicant's knowledge, there is no hybrid solution that allows a stored electrical energy source to be recharged in flight from the electrical energy production source, both with regard to the technical limitations mentioned above and the regulatory constraints that impose an architecture that does not include any single point of failure.

[0011] The invention improves the situation. To this end, it proposes an in-flight charging control device for a hybrid aircraft comprising at least one electrical generation source and at least two stored electrical energy sources each associated with at least one electrical switch, comprising a matcher arranged to receive a state indicator of each electrical generation source as well as a state indicator of each stored electrical energy source, to determine one or more load groups each associating an electrical generation source with two stored electrical energy sources, and to transmit each load group to a respective supervisor, each supervisor being arranged to implement a state machine chosen from the group comprising a stop state, a wait state, a unit precharge state, a unit charge state, a grouped precharge state, a coupling state and a grouped charge state,to retrieve input data comprising a current state of a state machine, an aircraft group load indicator, a state indicator and a current intensity indicator of the electrical generation source of its load group, a load indicator, a voltage indicator and a maximum available power indicator for each stored electrical energy source of its load group, to determine a new current state of the state machine from the input data, as well as a direct current setpoint for each stored electrical energy source of its load group, and to transmit the new current state of the state machine and the direct current setpoints to a load parameter calculator. The load parameter calculator is arranged to determine, for each stored electrical energy source, a direct voltage setpoint, a direct current to direct voltage transition setpoint,a charging stop indicator and a forced charging indicator based on the current state of the state machine and the direct current instructions of each supervisor as well as an instruction for opening or closing the electrical switches associated with the stored energy sources to allow electrical grouping of these.

[0012] Thanks to the supervisors, the device of the invention makes it possible to stagger and sequence the charges of the stored electrical energy sources and manage their implementation. simultaneous charging at the appropriate time. This staggering and the resulting simultaneous charging makes it possible to reduce recharging times by parallelizing certain stored electrical energy sources when the voltage levels are sufficiently close. In addition, the device according to the invention makes it possible to take into account the electrical architecture of the hybrid propulsion system and in particular the number of stored electrical energy sources as well as electrical generation sources to allow parallel recharging of the energy sources so that no single point of failure is created.

[0013] The supervisors can be implemented at several computing locations in the aircraft, but must be on board in order to manage in-flight recharging cases. It is not possible for them to be implemented in a ground-based recharging terminal, for example. In addition, in the event of a degraded state after a breakdown, the device of the invention makes it possible to receive the health statuses of the stored electrical energy sources in order to isolate those which must be isolated and not group them with the others.

[0014] According to various embodiments, the invention may have one or more of the following characteristics: - each supervisor is software instantiated based on the transmission by the peer, - supervisors are always available, and in which the call by the peer creates a link between each supervisor and a load group, - the matcher is arranged to determine one or more load groups comprising more than two stored electrical energy sources, - the pairer is arranged to access charge groups which are defined for a duration of operation of the device corresponding to a flight, and - the matcher is arranged to determine load groups dynamically.

[0015] The invention also relates to an energy management system for an aircraft with a hybrid energy source comprising at least one rechargeable electricity source and one electricity generation source, characterized in that it comprises: - a detector arranged to determine on the one hand status data indicating a status of the elements of the electrical power consumption circuit of the aircraft controlled by the energy management system, and on the other hand energy data relating to the instantaneous electrical power required by the aircraft and / or the charging status of the rechargeable electricity sources of the aircraft, - an automaton arranged to receive the energy data from the detector and to determine a control state of the energy sources, the automaton comprising at least three states in the group comprising: * a buffer state in which the instantaneous electrical power demanded is in lower than the capacity of the electricity generation source(s) and is supplied by the latter, * a state of charge in which the instantaneous electrical power required is less than the capacity of the electrical generation source(s) and is supplied entirely by the electricity generation source(s), and in which the electricity generation source(s) produces surplus power used to recharge the rechargeable electricity source(s), * a turbo state in which the instantaneous electrical power required is greater than the capacity of the electrical generation source(s), and where the rechargeable electricity source(s) provide the necessary supplement to achieve the instantaneous electrical power required, - an adapter arranged to receive the status data and to determine a backup electrical configuration when the status data indicates a fault, - a driver arranged to receive the status information from the automaton and to determine an electrical command for the rechargeable electrical source(s) and the electrical generation source(s) as a function of the instantaneous electrical power requested, - a switch arranged to issue commands to the switches of the aircraft power consumption electrical circuit controlled by the energy management system to implement a nominal electrical configuration, or, in the event of receipt of a backup electrical configuration from the adapter, this backup electrical configuration, and - an in-flight charging control device according to the invention arranged to communicate with the pilot and the switch to control the charging of the aircraft's rechargeable electricity sources.

[0016] Other characteristics and advantages of the invention will appear more clearly on reading the following description, taken from examples given for illustrative and non-limiting purposes, taken from the drawings in which: - [Fig.l] represents a schematic diagram of an aircraft comprising a device according to the invention, - [Fig.2] represents a generic diagram of the energy management system of [Fig.l], - [Fig.3] represents a generic diagram of the in-flight recharging control device of [Fig.2], - [Fig.4] represents an example of configuration in case of failure, and - [Fig.5] represents a state machine implemented by the device of [Fig.3].

[0017] The following drawings and description contain, for the most part, elements of certain character. They may therefore not only serve to better understand the present invention, but also contribute to its definition, where appropriate.

[0018] [Fig.l] represents a schematic diagram of an aircraft 2 comprising a device 4 according to the invention.

[0019] As can be seen in [Fig.l], an aircraft 2 according to the invention comprises an energy management system 4 according to the invention, two horizontal drive groups 6 and 8, four vertical drive groups 10, 12, 14 and 16, and two electrical generation sources 18 and 20.

[0020] This type of aircraft is extremely innovative and is particularly suitable for demonstrating the potential of the energy management system 4. However, the aircraft could have a simpler architecture, for example a single horizontal drive unit, one or two vertical drive units and a single source of electrical generation.

[0021] Still as a variant, the aircraft could not be of the VTOL type, but be of another type, for example a “classic” hybrid aircraft with conventional takeoff (also called CTOL for Conventional Take-Off and Landing in English). In this case, the vertical training groups will generally be called takeoff training groups, while the horizontal training groups will generally be called cruise training groups. Still as a variant, there will no longer be a distinction between two training groups of distinct types.

[0022] In the example described here, the horizontal drive unit 6 (respectively 8) comprises a direct current to alternating current converter 22 (respectively 32), an electric motor 24 (respectively 34) and a propeller 26 (respectively 36), for example a propeller. The propeller 26 (respectively 36) is arranged to allow the aircraft to move forward in a substantially horizontal direction. In the example described here, the propeller 26 (respectively 36) consumes a power of 80kW in flight mode.

[0023] The horizontal drive group 6 (respectively 8) is connected at the input to a switch 28 (respectively 38) which makes it possible to connect this input to the output of the vertical drive group 10 (respectively 14) or 12 (respectively 16), as described below.

[0024] The vertical drive group 10 (respectively 12, 14, 16) comprises a rotor 42 (respectively 46, 72, 76) driven by a motor 52 (respectively 56, 82, 86), a rotor 44 (respectively 48, 74, 78) driven by a motor 54 (respectively 58, 84, 88). The motors 52 and 54 are powered by a respective direct current to alternating current converter 62 and 64 (respectively 66 and 68, 92 and 94, 96 and 98). The direct current to alternating current converters can also be called "inverters" - or "inverters" in English - and are arranged to generate an alternating current at from a direct current.

[0025] The direct current to alternating current converters 62 and 64 (respectively 66 and 68, 92 and 94, 96 and 98) are connected to an electrical bus of the vertical drive group 10 (respectively 12, 14, 16), to which a battery 50 (respectively 60, 80, 90) is connected as well as an input connected to an electrical distribution bus 108 of the electrical generation source 18, an input connected to an electrical distribution bus 110 of the electrical generation source 20. The batteries each constitute a source of stored electrical energy, the coupling of which with the electrical generation sources establishes the hybrid nature of the invention.

[0026] Finally, the electrical bus of each of the vertical drive groups 10 and 12 (respectively 14 and 16) is connected to a respective output of the latter, which is connected to the switch 28 (respectively 38). As will be seen below, the batteries 50, 60, 80 and 90 together deliver 600kW when they deliver 100% of their capacity.

[0027] In the example described here, each electrical generation source 18 (respectively 20) comprises on the one hand a turbine generator 100 (respectively 102) and an alternating current to direct current converter 104 (respectively 106). In the example described here, each turbine generator can deliver 40 kW at 100% of its capacity. Alternatively, the electrical generation sources could be other electricity production sources, direct or alternating current followed by an alternating current to direct current converter or a direct current to direct current converter. Thus, these sources could be based on turbine generators powered by conventional fuel, biofuel, or synthetic fuels. Still as a variant, a hydrogen-based energy source, such as a fuel cell, could be used.

[0028] As will be seen with [Fig.2], the energy management system 4 is arranged to control on the one hand the electrical generation sources 18 and 20, on the other hand the switches 28 and 38, but also various protection elements not shown in [Fig.l].

[0029] When analyzing [Fig.l], it appears that all the motor and electrical elements are duplicated. Thus, one-fail-safe can be ensured. Indeed, there are two horizontal drive groups, four vertical drive groups themselves forming two subgroups connected to the same horizontal drive group, and two sources of electrical generation.

[0030] Beyond this fairly conventional duplication, it is the electrical buses specific to each vertical drive group, as well as the electrical distribution bus 108 and 110 specific to each source of electrical generation which make it possible to achieve the one-fail-safe objective in operation of “discharging” the energy sources. stored electricity, that is, when the stored electrical energy sources are stopped or supplying electric current to the electric motors.

[0031] In the case of recharging these stored electrical energy sources by one or more electrical generation groups, an obvious method of recharging the electrical energy storage sources would be complete paralleling at the level of the electrical buses 108 and 110. This method would then have the disadvantage of creating a SPOF as described previously.

[0032] Indeed, as will be seen below, the particular structure of the aircraft in [Fig.l] allows for a real hybridization of the electrical energy sources, as opposed to existing solutions in which it is a juxtaposition. Thus, depending on the power requirements, both the batteries and the electrical generation sources can operate in concert. But beyond that, this architecture allows the batteries to be treated as pure "energy buffers". The batteries are treated in a completely passive manner, without any need for software or hardware intelligence other than the basic intelligence required to operate the battery system (better known by the English acronym BMS for "Battery Management System"). Such a system makes it possible to perform functions such as monitoring parameters - voltage, temperature, state of charge, state of health, etc.-, the prevention of any risk of going outside the intended operating range - overvoltage, overcurrent, overheating, etc. - or even the optimization of battery capacity. This goes completely against all existing solutions, in which either an element is specifically designed to optimize the operation of the batteries, and plays a control role, or an element is designed to compensate for any weakness of the batteries, but in exclusive alternation, that is to say without the batteries and this element being likely to operate simultaneously.

[0033] [Fig. 2] represents a schematic diagram of the energy management system 4 of [Fig. 1]. As can be seen in this figure, the energy management system 4 comprises a detector 200, a controller 210, an adapter 220, a driver 230, a switch 240 and a recharge control device 250.

[0034] The detector 200 is a system arranged to receive various data from the aircraft 2, which it will optionally process and transmit totally or in part on the one hand to the automaton 210, and on the other hand to the adapter 220.

[0035] Thus, the data received by the detector 200 are of two main types: - on the one hand, state data indicating a state (load level, temperature, limit, operating state, fault state, etc.) of the elements of the electrical power consumption circuit of the aircraft controlled by the energy management system 4, and - on the other hand, energy data relating to the instantaneous electrical power required by the motors 52, 54, 56, 58, 82, 84, 86, 88 of the rotors 42, 44, 46, 48, 72, 74, 76, 78 and / or the motors 24 and 34 of the propellers 26 and 36, and / or the state of charge of the rechargeable electricity sources of the aircraft 50, 60, 80 and 90.

[0036] Thus, the detector 200 has an overall view of the functional state of the elements linked to the consumption of electrical power, that is to say on the one hand the presence of a breakdown or not as well as the flight phase of the aircraft 2, but also of the energy state of these elements, that is to say their instantaneous state as well as the instantaneous electrical power demand linked to the flight of the aircraft 2, as determined in response to the commands of the FMS.

[0037] In the following, the expression instantaneous electrical power requested will always designate the electrical power which is called by the motors 52, 54, 56, 58, 82, 84, 86, 88 of the rotors 42, 44, 46, 48, 72, 74, 76, 78 and / or the motors 24 and 34 of the thrusters 26 and 36, unless another definition is explicitly mentioned.

[0038] The automaton 210 is in the example described here a finite automaton, an example of which is shown in [Fig. 3]. As can be seen in this figure, the automaton 210 has four possible states: - a state 300 called “buffer”, in which the instantaneous electrical power requested is less than the capacity of the electrical generation source(s) 18 and 20, and is supplied by the latter, - a state 310 called “charging”, in which the instantaneous electrical power requested is less than the capacity of the electrical generation source(s) and is supplied entirely by the electricity generation source(s), and in which the electricity generation source(s) produces surplus power used to recharge the stored electrical energy source(s), - a state 320 called “turbo” in which the instantaneous electrical power requested is greater than the capacity of the electrical generation source(s), and where the rechargeable electricity source(s) provide the necessary supplement to reach the instantaneous electrical power requested, and - an optional state 330 called “silent”, in which the electrical energy sources 18 and 20 are voluntarily stopped in order to reduce noise pollution, which also makes it possible to reduce the emission of pollutants.

[0039] The automaton 210 has transitions which are provided to ensure: - on the one hand, minimal risk in determining state transitions, in order to limit the risks of failure linked to the automaton 210 (and therefore to the energy management system 4), - on the other hand, recharging the 50, 60, 80, 90 batteries as frequently as possible.

[0040] For this reason, state transitions rely on two variables: - the instantaneous electrical power required, - the battery recharge rate 50, 60, 80, 90.

[0041] As a priority, as soon as the instantaneous electrical power requested exceeds the electrical power capacity of the electrical generation sources 18 and 20, the buffer state or the charging state switches to the turbo state. Indeed, in this case, it is crucial to operate the batteries 50, 60, 80, 90 and the electrical generation sources 18 and 20 simultaneously in order to provide sufficient electrical power to implement the flight controls.

[0042] Secondarily, when the instantaneous electrical power required is less than the electrical power capacity of the electrical generation sources 18 and 20, the priority is to recharge the batteries.

[0043] Thus, the automaton 210 can transition from the buffer state to the charging state or to the turbo state, and from the charging state to the turbo state, and it can transition from the charging state to the buffer state or from the turbo state to the buffer state. On the other hand, it cannot transition from the turbo state to the charging state: it must first transition to the buffer state.

[0044] The reason for this is that, in this way, each state transition is conditioned by a single change of condition relating either to the instantaneous electrical power requested, or to the state of charge of the batteries. Thus, the reliability of the automaton 210 is improved because the risks of several successive transitions or non-transitions are minimal.

[0045] The silent state 330 is for its part an option in the sense that it depends on manual activation by the pilot of the aircraft 2. Thus, the latter sends a command to switch off the electrical generation sources 18 and 20 which causes any state to transition to the silent state. In the same way as for the charge and turbo states, when this command is deactivated, the automaton 210 transitions again to the buffer state.

[0046] The buffer state thus constitutes a starting state and a fundamental state in that it makes it possible to make the operation of the automaton 210 more reliable. It should be noted that the parameters defining the transitions can be varied. Thus, the transition from the buffer state to the charging state can be conditioned by a charging threshold of the batteries 50, 60, 80, 90, and this threshold can itself be modified according to the operational, functional state and / or the flight program of the aircraft 2. Similarly, the electrical power capacity of the electrical generation sources 18 and 20 can be modified according to the operational, functional state and / or the flight program of the aircraft 2. For example, in certain cases of failure, it may be necessary to operate one or more of the electrical generation sources 18 and 20 at a capacity greater than their nominal capacity, for example 120%. It is then necessary to adapt the transition threshold to the turbo state accordingly. This adaptation is carried out in the example described here by the adapter 220 which adapts the transition threshold, and by the driver 230 which sends this information to the control card of the electrical generation source (respectively to the control cards of the electrical generation sources).

[0047] Still as a variant, the switch to the silent state could not be purely manual, but take into account the environment of the aircraft 2, for example taking into account one or more parameters among the flight height and a geographical location.

[0048] The adapter 220 is arranged to receive the status data from the detector 200. Based on this, the adapter 220 can determine a fault status and a corresponding emergency electrical configuration. For example, if the status data received from the detector 200 indicates that the motor 52 has failed, then the adapter 220 determines that the vertical drive group 10 must be isolated, and it returns an electrical configuration indicating the need for this isolation and to turn off the elements it comprises.

[0049] The adapter 220 thus contains a table of all possible failure configurations, and the backup electrical configuration corresponding to each. Similarly, if the adapter 220 determines that no failure is occurring, then it can return a nominal electrical configuration which can for example take into account the flight phase of the aircraft 2. The fact that the adapter 220 contains a table with all possible failure configurations is intended to guarantee any error. Alternatively, the adapter 220 could operate from logical operations in order to determine the backup electrical configuration.

[0050] In practice, the electrical configuration, whether nominal or emergency, reflects the fact that isolation switches and / or extinguishing controls must be activated. Indeed, each element of the circuit of [Fig.l] is connected to the rest of the circuit by a switch (not shown), and the consumers and producers of energy are furthermore controlled to switch on or off.

[0051] If we return to the example of the failure of the motor 52, then the adapter 220 determines a backup electrical configuration which isolates the vertical drive group 10 as shown in [Fig. 4]. This results in a backup electrical configuration which indicates that all the switches within the vertical drive group 10, i.e. the switch between the AC to DC converter 104 and the input of the vertical drive group 10 connected to the DC to AC converter 62, the switch between the AC to DC converter 106 and the input of the vertical drive group 10 connected to the DC to AC converter 64, the switch between battery 50 and the rest of vertical drive group 10, and a shutdown control for motors 52 and 54. This emergency electrical configuration also indicates that all switches within vertical drive group 12 must be activated to switch power to that group, as well as switch 28 which must switch to vertical drive group 12.

[0052] The driver 230 receives on the one hand the state of the automaton 210, and on the other hand the electrical configuration of the adapter 220. On this basis, the driver 230 can control the rechargeable electricity sources 50, 60, 80 and 90 and / or the electricity generation sources 18 and 20 according to the energy regime corresponding to the state of the automaton 210 and extinction information indicated by the electrical configuration of the adapter 220.

[0053] For example, in the takeoff phase, with the silent state activated, the pilot 230 sends a command to switch off the electricity generation sources 18 and 20. By switching off, it must be understood that the pilot 230 issues a command to electrically disconnect the elements considered from the electrical system. In practice, this command can result in a so-called “super idle” regime where the energy sources concerned operate at a hyper-idle regime, which avoids switching them off for safety reasons (risk of restart problems).

[0054] Still as a variant, this extinction can be translated by an electrical extinction in the literal sense of the term: - in the take-off phase, with the state of charge, the pilot 230 sends a command to increase the power of the electricity generation sources 18 and 20 to reduce the power emitted by the batteries 50, 60, 80 and 90 to 0, - in the take-off phase, with the turbo state, the pilot 230 sends a command to increase the power of the electricity generation sources 18 and 20 to their maximum capacity, - in the cruise flight phase, with the state of charge, the pilot 230 sends a command to increase the power of the electricity generation sources 18 and 20 until the power emitted by the batteries 50, 60, 80 and 90 is equal to the inverse of the recharging power indicated by the BMS (i.e. in practice the batteries receive this recharging power), - in the cruise flight phase, with the buffer state, the pilot 230 sends a command to increase the power of the electricity generation sources 18 and 20 to reduce the power emitted by the batteries 50, 60, 80 and 90 to 0, - in the descent phase, with the buffer state, the pilot 230 sends a command to increase the power of the electricity generation sources 18 and 20 to reduce the power emitted by the batteries 50, 60, 80 and 90 to 0, - in the landing phase, with the buffer state, the pilot 230 sends a command to increase the power of the electricity generation sources 18 and 20 to reduce the power emitted by the batteries 50, 60, 80 and 90 to 0, - in the landing phase, with the turbo state, the pilot 230 sends a command to increase the power of the electricity generation sources 18 and 20 to their maximum capacity, etc.

[0055] The switch 240 is arranged to perform a binary AND type operation between, on the one hand, the configuration emitted by the adapter 220, and on the other hand, the electrical configuration induced by the state of the automaton 210. Thus, if we take the example of the failure of the motor 52, while the state of the automaton 210 is the turbo state, then, for the switches of the vertical drive group 10, this operation will be 0 (resulting from the isolation controlled by the emergency electrical configuration emitted by the adapter 220) x 1 (resulting from the turbo state) which will return 0 for these switches. Once the state of all the switches in the circuit has been determined by the switch 240, the corresponding commands are sent to all the switches in the circuit, and the loop from the detector 200 can resume.

[0056] Thus, it appears that: - all the elements of the circuit consuming or producing power are connected to the detector 200 to indicate their state, - all elements of the circuit which provide power are controlled by the driver 230, - all on / off switches and controls are controlled by switch 240.

[0057] Thus, the energy management system of the invention completely separates the management of the power production mode (via the automaton 210) and the management of the electrical configuration of the circuit to consume this power (via the adapter 220). The driver 230 and the switch 240 are elements of a deliberately simplified nature so as to each receive the outputs of the automaton 210 and the adapter 220 and to be able to take these outputs into account to control the power suppliers and the switches respectively.

[0058] This decorrelation of the control of the electrical circuit is particularly innovative and interesting in that it establishes an architecture which can be deployed quickly and reliably on all types of hybrid aircraft, regardless of the redundancy of their design.

[0059] Finally, the charge control device 250 receives information from the automaton 210 and the adapter 220, and transmits data to the pilot 230 and the switch 240. The role of the charge control device 250 is to interact with the various energy management elements in the aircraft 2 in order to manage the recharging of the sources of stored electrical energy, and in particular to allow grouped charging (or "pooling" in English).

[0060] [Fig. 5] represents an example of implementation of the load control device 250. The load control device 250 comprises a matcher 500, one or more supervisors 510 to 5 In and a load parameter calculator 520.

[0061] The respective roles of these elements are as follows: - the function of the pairer 500 is to create tuples associating at least two sources of stored electrical energy with a source of electrical generation, - each tuple is transmitted to a supervisor 510 to 51n. There are therefore as many supervisors as there are tuples. In practice, there will generally be as many supervisors as there are active electrical generation sources. Each supervisor has the function of determining, from a state machine and the data received from the automaton 210 and the adapter 220, the optimal load configuration of the electrical energy sources stored by the electrical generation source of its triplet, and - the load parameter calculator 520 is arranged to receive the load configurations from each of the supervisors, and to transmit in return the necessary control data to the driver 230 and the switch 240.

[0062] The load control device 250 which is the subject of the invention is thus based on the combination of three principles which allow coupled in-flight charging while ensuring redundancy and preventing the creation of a SPOF: 1) the definition of load groups which combine a source of electrical generation and one or more sources of stored electrical energy to be recharged. 2) control of the behavior of a load group based on information on the status of the aircraft and the elements of the load group using a state machine whose control makes it possible to prevent any risk. 3) grouping the information from each load group to return control and status information to the aircraft and control the load.

[0063] In the preferred embodiment, the pairer 500 is executed only once per flight, preferably before takeoff. To operate, the pairer 500 receives as input data a status indicator of each electrical generation source as well as a status indicator of each stored electrical energy source. Thus, the pairer 500 can associate each electrical generation source with two stored electrical energy sources to form a load group each time. In the case where one or more stored electrical energy source status indicators indicate unavailability, the pairer 500 may be required to associate only one stored electrical energy source with an electrical generation source.Alternatively, more than two sources of stored electrical energy can be associated with a load group. Once the load groups have been determined, they are each transmitted to a supervisor. 510 to 51n respectively. This transmission can be done in the form of a software instantiation of a supervisor for each load group, or by transmitting the load group as a runtime variable to a supervisor.

[0064] Furthermore, in the example described here, the matcher 500 is executed only once for each flight, preferably before takeoff. This means that once the load groups are defined, they do not change until the next flight. Alternatively, the matcher 500 could be executed regularly during flights, or when a particular event occurs. It may then be useful for the matcher 500 to receive such event data as additional input data (for example, the recovery or loss of one or more sources of stored electrical energy, charging prohibition information, or the like). In the case of the embodiment described here, the state determined by the automaton 210 could for example be useful.

[0065] In the embodiment described here, each supervisor 510 at 5 In receives as input data: a current state of state machine, an aircraft grouped load indicator, a state indicator and a current intensity indicator of the electrical generation source of its load group, a load indicator, a voltage indicator and a maximum power indicator available for each stored electrical energy source of its load group.

[0066] These various inputs make it possible to determine several transition conditions between the various states of the state machine. The state machine has the following states in the example described here: a stop state, a wait state, a unit precharge state, a unit charge state, a group precharge state, a coupling state and a group charge state.

[0067] In the shutdown state, the supervisor is stopped. This may be the case, for example, because the status indicator of the electrical energy generation source indicates a failure, or because one or more stored electrical energy sources indicate a failure.

[0068] The waiting state is the basic state of the supervisor, and a necessary passage to move from a state associated with a unit load to a state associated with a grouped load.

[0069] The unit precharge state is a state that the supervisor must transition to from the standby state before implementing the unit charge state. This state makes it possible to guarantee a unit charge mode for the load group when the stored electrical energy sources have significantly different charge levels.

[0070] The unit charge state is a state in which one of the stored electrical energy sources is being recharged. This may be necessary when only one of the stored electrical energy sources in a charging group needs to be charged, or when the voltage level of one of the stored electrical energy sources needs to be brought back to a level high enough to allow group charging.

[0071] The group precharge state is a state that the supervisor must transition to from the standby state before implementing the group charge state. This state ensures that the stored electrical energy sources of the load group have charge levels close enough to implement a group charge mode.

[0072] The coupling state is a state that precedes the grouped charging state and is necessarily preceded by the grouped precharging state. This state serves to ensure the electrical paralleling of the sources of electrical energy stored within a given charging group.

[0073] Finally, the grouped charging state is a state in which several sources of stored electrical energy are recharged simultaneously by the electrical generation source of the charging group to which they belong.

[0074] The transition from the standby state to the unit precharge state may for example be caused by a grouped charge indicator of the aircraft being set to zero (i.e. prohibiting grouped charge), as well as a status indicator and a current intensity indicator of the electrical generation source indicating that power is available, while the charge indicator of at least one of the stored electrical energy sources indicates that charging is possible (for example in a binary manner or because the charge indicator is below a charge threshold).

[0075] The transition from the unit charge state to the standby state may be caused by the receipt of a group charge indicator from the aircraft which indicates that group charging is possible, or by the fact that the charge indicator of a stored electrical energy source being charged indicates that charging is no longer possible.

[0076] Thus, each supervisor is arranged to determine at regular intervals a new current state of the state machine from the input data, as well as a direct current setpoint for each stored electrical energy source of its load group. The determination of the direct current setpoint makes it possible to process in a completely passive manner, without any need for software or hardware intelligence other than their BMS.

[0077] Preferably, each supervisor is arranged to simulate the operation of the BMS of the stored electrical energy sources of its storage group in order to leave no processing to the latter. This makes it possible in particular to control the charging method, which can be advantageously based on the CC-CV model, i.e. in a first step, the stored electrical energy source is charged at constant current (hence the direct current setpoint), until a chosen voltage level is reached in the stored electrical energy source. In a second step, the charging continues this time at constant voltage, until the current indicates that the charging is finished. This charging paradigm is well known and fits particularly well into the state machine described for supervisors.

[0078] Once each supervisor has updated its current state and the DC setpoint of each stored electrical energy source, these are transmitted to the load parameter calculator 520 which will produce two parameter structures, one of which is intended for the aircraft management system and the other for the BMS of the stored electrical energy sources. In the embodiment described above, the first structure is sent to the switch 240, while the second structure is sent to the pilot 230.

[0079] In the example described here, the first structure thus comprises a matrix of load groups, which makes it possible both to organize the electrical switching to direct the electrical current coming from the electrical generation sources to the stored electrical energy sources paired by the pairer 500 and on the other hand a load mode vector which indicates for each load group whether it is in unit load (and in this case on which stored electrical energy source), in grouped load, or on standby.

[0080] In the example described here, the second structure comprises the concatenation of five BMS control values of each stored electrical energy source: - the constant current setpoint (used for CC charge mode), - the constant voltage setpoint (used by CV charge mode), - a charge stop indicator, - a charge trigger indicator, and - the end of charge current threshold.

[0081] Conventionally, the charge stop indicator takes precedence over all other data. Thus, if the current state of the state machine is a unit or coupled charge and the charge stop indicator is activated by the BMS of the stored electrical energy source concerned, whether for a fault reason or otherwise, the state machine will automatically go into a waiting state. The charge trigger indicator is for its part activated in a conventional manner when the charge stop indicator is deactivated and the unit precharge state or the coupling state is activated and the state machine determines that unit charge or grouped charge is now possible.

[0082] It is clear from the above that the different states of the state machine make it possible to very finely divide each step of the charging, in a grouped or non-grouped manner, of a stored electrical energy source. This results in securing the charging control device 250 which can at any time control the charging state and guarantee charging in flight, optimized for each stored, or even grouped, electrical energy source, and without the risk of SPOF.

[0083] The paradigm described above is particularly advantageous because it allows, from of a highly generalist architecture, to adapt the load control device to a very large number of implementations, without having to recreate the architecture.

[0084] Indeed, in the embodiment described above, the aircraft is a VTOL whose EMS itself implements a state machine. Also, the charge control device 250 is naturally integrated into the energy management system 4. Nevertheless, it appears that the charge control device 250 could be integrated as a separate module in any hybrid aircraft, since it receives the global information from the aircraft (such as failures, flight phases prohibiting recharging, instantaneous states of the elements, etc.) and the latter can receive its information to implement the recharging command.

[0085] In addition, its architecture offers great flexibility: if the electrical generation sources are connected to only some of the stored electrical energy sources, then the matcher will perform an association constrained by this physical reality, but if this is not the case, it may for example be envisaged to regularly execute the matcher in order to modify the load groups to associate the stored electrical energy sources whose voltage levels are closest. Still alternatively, although the load groups described here each contain a maximum of two stored electrical energy sources, this number may be increased.

[0086] The definition of load groups makes it possible to instantiate the supervisors according to the needs identified by the matcher. This means that the consumption of computing resources can be optimized by activating only the supervisors that are necessary. In the same way, the separation between supervisors and load parameter calculator makes it possible to separate the processing and therefore prevent the risks of SPOF. For example, if a supervisor does not respond, the load parameter calculator can continue to operate with the other load groups and signal to the aircraft management system that there is a potential problem for the load group associated with this supervisor.

[0087] The charge control device according to the invention therefore offers an algorithm using a state machine making it possible to carry out a sequencing of the charging of the batteries associated in a charging group until they are brought back to a voltage level difference deemed acceptable, then a paralleling of these batteries to carry out a grouped charge (or "pooled" in English) of these batteries.

[0088] Beyond the possibility of grouped charging, the invention not only makes it possible to offer the most flexible in-flight battery recharging strategy possible, but also to guarantee the possibility of in-flight recharging at all, which is not known to date when the absence of SPOF must be guaranteed.

Claims

Claims

1. In-flight charging control device for hybrid aircraft comprising at least one source of electrical generation and at least two sources of stored electrical energy each associated with at least one electrical switch, comprising - a matcher (500) arranged to receive a status indicator of each electrical generation source as well as a status indicator of each stored electrical energy source, to determine one or more load groups each associating an electrical generation source with two stored electrical energy sources, and to transmit each load group to a respective supervisor (510,51n), - each supervisor (510,51n) being arranged to implement a state machine chosen from the group comprising a stop state, a wait state, a unit precharge state, a unit charge state, a grouped precharge state, a coupling state and a grouped charge state, to retrieve input data comprising a current state machine state, an aircraft grouped charge indicator, a state indicator and a current intensity indicator of the electrical generation source of its load group, a load indicator, a voltage indicator and a maximum available power indicator for each stored electrical energy source of its load group, to determine a new current state machine state from the input data, as well as a direct current setpoint for each stored electrical energy source of its load group,and to transmit the new current state of the state machine and the direct current setpoints to a load parameter calculator, - the load parameter calculator (520) being arranged to determine, for each stored electrical energy source, a DC voltage setpoint, a DC to DC voltage transition setpoint, a load stop indicator and a forced load indicator from the current state of the state machine and the DC current setpoints of each supervisor as well as an opening or closing setpoint for the electrical switches associated with the stored energy source to allow electrical grouping thereof.

2. A control device according to claim 1, wherein each su- monitor (510,51n) is software instantiated based on the transmission by the peer (500).

3. A control device according to claim 1, wherein the supervisors are always available, and wherein the call by the pairer (500) creates a link between each supervisor (510,51n) and a load group.

4. Device according to one of the preceding claims, in which the matcher (500) is arranged to determine one or more load groups comprising more than two sources of stored electrical energy.

5. Device according to one of the preceding claims, in which the pairer (500) is arranged to access charge groups which are defined for an operating duration of the device corresponding to a flight.

6. Device according to one of claims 1 to 4, wherein the matcher (500) is arranged to determine the load groups dynamically.

7. Energy management system for aircraft with hybrid energy source comprising at least one rechargeable electricity source and one electricity generation source, characterized in that it comprises: - a detector (200) arranged to determine on the one hand state data indicating a state of the elements of the electrical power consumption circuit of the aircraft controlled by the energy management system, and on the other hand energy data relating to the instantaneous electrical power requested by the aircraft and / or the charging state of the rechargeable electricity sources of the aircraft, - an automaton (210) arranged to receive the energy data from the detector (200) and to determine a control state of the energy sources,the automaton (210) comprising at least three states in the group comprising: * a buffer state in which the instantaneous electrical power requested is less than the capacity of the electrical generation source(s) and is supplied by the latter, * a charging state in which the instantaneous electrical power requested is less than the capacity of the electrical generation source(s) and is supplied entirely by the electricity generation source(s), and in which the electricity generation source(s) produces surplus power used to recharge the rechargeable electricity source(s), * a turbo state in which the instantaneous electrical power required is greater than the capacity of the electrical generation source(s), and where the rechargeable electricity source(s) provide the necessary supplement to achieve the instantaneous electrical power required, - an adapter (220) arranged to receive the status data and to determine a backup electrical configuration when the status data indicates a failure, - a driver (230) arranged to receive the status information from the automaton (210) and to determine an electrical command for the rechargeable electrical source(s) (50, 60, 80, 90) and the electrical generation source(s) (18, 20) as a function of the instantaneous electrical power requested, - a switch (240) arranged to issue commands to the switches of the power consumption electrical circuit of the aircraft controlled by the energy management system to implement a nominal electrical configuration, or, in the event of reception of a backup electrical configuration from the adapter (220), this backup electrical configuration, and - an in-flight charging control device according to one of the preceding claims arranged to communicate with the pilot (230) and the switch (240) to control the charging of the rechargeable electricity sources of the aircraft.

Images