Power sharing in an aircraft using distributed control

Abstract

The invention relates to a system (100) for exchanging power in an aircraft, the system comprising: - a voltage bus (160); - a low-pressure electromechanical converter (150 BP); - a high-pressure electromechanical converter (150 HP); and - for each electromechanical converter (150 BP, 150 HP), a voltage control module (125 BP, 125 HP). The system (100) further comprises: - a computer (106) designed to provide a sharing setpoint (S) between the exchanged powers (PHP, PBP), this sharing setpoint (S) varying over time; and - for at least one of the electromechanical converters (150 BP, 150 HP): a module (120 BP, 120 HP) for ensuring that the sharing setpoint (S) is observed, which module is designed to adjust the power (PHP, PBP) that is exchanged by the relevant electromechanical converter (150 BP, 150 HP) in order to observe the received sharing setpoint (S), taking into account a received evaluation (PBP°, PHP°) of the power (PBP, PHP) exchanged by the other of the electromechanical converters (150 BP, 150 HP).

Description

Description TITLE: POWER SHARING IN AN AIRCRAFT USING DISTRIBUTED CONTROL Technical field of the invention

[0001] The present invention relates to a power exchange installation in an aircraft, a propulsion system of an aircraft comprising such an installation, an aircraft comprising such a propulsion system, and a corresponding method. Technological background

[0002] In a context of reducing the ecological footprint of aircraft, electric hybridization appears to be a technological solution making it possible to significantly improve the environmental performance of aircraft by reducing their fuel consumption in particular.

[0003] Thus, power exchange installations in an aircraft are known in the prior art, comprising: - a voltage bus designed to have a bus voltage; - a so-called low pressure (LP) electromechanical converter designed to exchange power between the voltage bus and a low pressure body of a turbomachine of the aircraft; - a so-called high pressure (HP) electromechanical converter designed to exchange power between the voltage bus and a high pressure body of the turbomachine of the aircraft; and - for each electromechanical converter, a voltage regulation module, designed to regulate the bus voltage by controlling the electromechanical converter in question in order to adjust the exchanged power.

[0004] The voltage bus is generally part of an aircraft electrical network, which electrical network may further include sources and / or loads connected to the voltage bus.

[0005] In this way, the electromechanical converters form an interface between the HP and LP bodies of the turbomachine and the aircraft's electrical network.

[0006] To ensure the proper functioning of loads in particular, the bus voltage must remain within a predefined range, which is enabled by the bus voltage regulation modules associated with the electromechanical converters.

[0007] These regulation modules can have a zero static bus voltage error, which has the advantage that the bus voltage remains very close to its setpoint. However, these two bus voltage regulations are independent of each other and can compete, leading to a power sharing drift, with one electromechanical converter exchanging all the power and the other none.

[0008] One of the solutions proposed in the prior art to this problem is a so-called "decentralized" installation implementing a droop control which, by defining appropriate droop coefficients, allows the power sharing between the power exchanged by the low-pressure body and the power exchanged by the high-pressure body to be defined. However, the bus voltage regulation modules then have a non-zero static error, so that the bus voltage remains far from its setpoint, which can lead it to go outside the gauge during a power call by a load from the electrical network or during a power supply by a source.

[0009] Furthermore, controlling power sharing depends heavily on the accuracy of the bus voltage measurement and requires a very precise acquisition chain (<1% error).

[0010] An alternative is that one of the two electromechanical systems must control the bus voltage and the other system must apply a power draw or supply instruction from the central computer.

[0011] However, this solution has the disadvantage of not being robust to the loss of the electromechanical system controlling the bus voltage. Indeed, the other system can reconfigure itself but there will be a loss of network electrically over a long period of time. Furthermore, the central computer must constantly send a setpoint to the system not performing voltage control.

[0012] Another solution of the prior art is to propose a so-called "centralized" installation, where an external computer regulates the bus voltage and applies or not a power withdrawal or supply instruction coming from the central computer and distributes the power or torque instructions to the two electromechanical converters.

[0013] This system has the advantage of being robust to the loss of one of the two electromechanical converters. The two electromechanical converters can then control the voltage and share the power to be drawn.

[0014] However, the dependency between the centralized computer and the two electromechanical converters requires the addition of fast communication (greater than 10kHz).

[0015] Furthermore, the Japanese patent application published under number JP 2014 131469 A describes two generators coupled to a turbomachine, and two regulators for respectively regulating these two generators. Each regulator is designed to receive a power ratio setpoint and the ratio of the current supplied by the associated generator to the total current supplied by the two generators. This ratio is calculated from measurements of the current supplied by each of the generators. Each regulator is thus designed to provide, to the associated generator, a voltage setpoint that the generator must supply, calculated by the value of a calibrated resistor in an output filter, which requires precise knowledge of this resistance value, which is difficult to obtain due in particular to variations in the environment (temperature, etc.).US Patent 11,355,929 is substantially similar, except that it does not describe the precise operation of the regulators and that the current ratio is calculated from measurements of the current supplied by the associated generator and measurements of the total current supplied by the two generators.

[0016] It may thus be desirable to provide a power exchange installation which makes it possible to overcome at least some of the aforementioned problems and constraints. Summary of the invention

[0017] A power exchange installation is therefore proposed in an aircraft, comprising: - a voltage bus designed to present a bus voltage; - a so-called low-pressure electromechanical converter designed to exchange power between the voltage bus and a low-pressure body of a turbomachine of the aircraft; - a so-called high-pressure electromechanical converter designed to exchange power between the voltage bus and a high-pressure body of the aircraft turbomachine; and - for each electromechanical converter, a voltage regulation module, designed to regulate the bus voltage by controlling the electromechanical converter in question in order to adjust the power exchanged by the electromechanical converter in question; characterized in that it further comprises: - a computer designed to provide a sharing instruction between the exchanged powers, this sharing instruction varying over time;and - for at least one of the electromechanical converters: · a communication module designed to receive the sharing instruction provided by the calculator and an evaluation of the power exchanged by the other of the electromechanical converters, and · a module for respecting the sharing instruction, designed to adjust the power exchanged by the electromechanical converter in question in order to respect the sharing instruction received, taking into account the evaluation received of the power exchanged by the other of the electromechanical converters. ;

[0018] Thus, thanks to the invention, it is possible to implement decentralized voltage regulation, i.e. independent from one electromechanical converter to another, and distributed power regulation, i.e. with a sharing of the powers exchanged by the electromechanical converters. This sharing can be defined and modified over time with the sharing instruction. Compliance with this sharing instruction thus makes it possible to avoid a drift in the power sharing.

[0019] The invention is particularly compatible with zero static error voltage regulations on each side, ensuring robustness in the event of loss or failure of regulation on one side.

[0020] A power exchange installation according to the invention may further comprise one or more of the following optional features, in any technically possible combination.

[0021] Optionally, the sharing setpoint compliance module is designed to adjust the power exchanged by the electromechanical converter in question by modifying a voltage setpoint so that the voltage regulation module of the electromechanical converter in question regulates the bus voltage to the modified bus voltage.

[0022] Also optionally, the sharing setpoint compliance module is designed to apply, in the voltage regulation module, a voltage correction to the voltage setpoint.

[0023] Applying a correction to a voltage setpoint ensures that in the event of a failure of the sharing setpoint compliance module so that it no longer provides correction (equivalent to zero correction), the voltage regulation module automatically continues to operate by regulating the voltage to the voltage setpoint. This thus prevents propagation of the failure.

[0024] Also optionally, each voltage regulation module comprises: - a setpoint determination module designed to determine an exchange setpoint for the electromechanical converter in question; and - a control module designed to control the electromechanical converter in question, so that the electromechanical converter in question respects the exchange setpoint.

[0025] Also optionally, the exchange instruction is a power instruction to be exchanged between the electromechanical converter considered and the voltage bus.

[0026] Also optionally, the exchange instruction is a current instruction to be exchanged between the electromechanical converter considered and the voltage bus or, the electromechanical converters each comprising an electrical machine coupled to the associated body, the exchange instruction is a torque instruction of the electrical machine.

[0027] Also optionally, the sharing instruction compliance module is designed to: - determining a desired exchange setpoint in order to respect the sharing setpoint received, taking into account the received evaluation of the power exchanged by the other of the electromechanical converters; and - regulating the exchange setpoint of the electromechanical converter considered to the desired exchange setpoint.

[0028] Also optionally, the sharing instruction compliance module includes: - a comparator designed to calculate an error between the desired exchange instruction and the exchange instruction; and - a corrector designed to calculate the voltage correction from the error.

[0029] Also optionally, the sharing instruction compliance module is designed to determine a desired exchange instruction in order to comply with the received sharing instruction taking into account the received evaluation of the power exchanged by the other of the electromechanical converters, and comprises: - a comparator designed to calculate a difference between, on the one hand, an error between the desired exchange instruction and the exchange instruction of the electromechanical converter considered and, on the other hand, an error between the desired exchange instruction and the exchange instruction of the other electromechanical converter; and - a corrector designed to calculate the voltage correction from the difference.

[0030] Also optionally, the corrector is zero static error.

[0031] Optionally also, the communication module is further designed to receive a sharing mode indication from among several predefined sharing modes, and the sharing instruction compliance module is further designed to determine the desired exchange instruction from the received sharing mode indication.

[0032] Also optionally, the predefined sharing modes include at least one of: - a proportional sharing mode, in which the received power sharing instruction is a ratio between the powers exchanged and in wherein the sharing instruction compliance module is designed to determine the desired exchange instruction by multiplying or dividing the received evaluation by the sharing instruction; and - a differential sharing mode, in which the received power sharing instruction is a difference between the exchanged powers, and in which the sharing instruction compliance module is designed to determine the desired exchange instruction by adding the received evaluation to the sharing instruction or by subtracting the received evaluation from the sharing instruction.

[0033] Optionally also, the installation further comprises a selection module designed to provide, on command, an exchange setpoint, called direct, to the control module of the electromechanical converter in question, instead of the exchange setpoint, so that the power exchanged by the electromechanical converter in question is regulated to the direct exchange setpoint.

[0034] Also optionally, the exchange instructions are power instructions to be exchanged.

[0035] Optionally also, the evaluation of the power exchanged by the other of the electromechanical converters is the power setpoint to be exchanged by the other of the electromechanical converters.

[0036] Optionally also, the evaluation of the power exchanged by the other of the electromechanical converters is a measurement of the power exchanged by the other of the electromechanical converters.

[0037] There is also provided a propulsion system for an aircraft comprising a turbomachine and an installation according to the invention.

[0038] An aircraft comprising a propulsion system according to the invention is also proposed.

[0039] There is also proposed a method for exchanging power in an aircraft, characterized in that it comprises: - for each of a so-called low pressure electromechanical converter and a so-called high pressure electromechanical converter, the low pressure electromechanical converter being designed to exchange power between a voltage bus designed to have a voltage of bus and a low-pressure body of a turbomachine of the aircraft, the high-pressure electromechanical converter being designed to exchange power between the voltage bus and a high-pressure body of the turbomachine of the aircraft, a regulation of the bus voltage by controlling the electromechanical converter in question in order to adjust the exchanged power; - a supply by a computer of a sharing instruction between the exchanged powers, this sharing instruction varying over time; and - for at least one of the electromechanical converters: · a reception of the sharing instruction provided by the computer and of an evaluation of the power exchanged by the other of the electromechanical converters, and · an adjustment of the power exchanged by the electromechanical converter in question in order to respect the sharing instruction received, taking into account the evaluation received of the power exchanged by the other of the electromechanical converters..

[0040] There is also provided a computer program downloadable from a communication network and / or recorded on a computer-readable medium, characterized in that it comprises instructions for executing the steps of a method according to the invention, when said program is executed on a computer. Brief description of the figures

[0041] The invention will be better understood with the aid of the following description, given solely by way of example and with reference to the appended drawings in which: - figure 1 is a simplified view of an installation according to the invention for exchanging power in an aircraft, - figure 2 is a view similar to that of figure 1, in a particular embodiment, - figure 3 is a functional view of a power sharing compliance module of the installation of figure 2, for a converter electromechanical converter said to be high pressure coupled to a high pressure body of a turbomachine, - figure 4 is a functional view of a power sharing compliance module of the installation of figure 2, for an electromechanical converter said to be low pressure coupled to a low pressure body of the turbomachine, - figure 5 is a functional view of a bus voltage regulation module of the installation of figure 2, for the high pressure electromechanical converter, - figure 6 is a functional view of a bus voltage regulation module of the installation of figure 2, for the low pressure electromechanical converter, - figure 7 is a functional view of a control module of the high pressure electromechanical converter, present in the installation of figure 2, - figure 8 is a functional view of a control module of the low pressure electromechanical converter, present in the installation of figure 2,- Figure 9 is a view similar to that of Figure 1, with selection modules for direct application of instructions, - Figure 10 is a view similar to that of Figure 9, in the particular case of Figure 2, - Figure 11 is a functional view of a power sharing compliance module of the installation of Figure 1, for the high-pressure electromechanical converter, - Figure 12 is a functional view of a power sharing compliance module of the installation of Figure 1, for the high-pressure electromechanical converter, - Figure 13 is a functional view of variants of the sharing compliance modules of Figures 3 and 4, and - Figure 14 is a functional view of variants of the sharing compliance modules of Figures 11 and 12., Detailed description of the invention

[0042] With reference to Figure 1, an example of a propulsion system 98 of an aircraft, in which the invention is implemented, will now be described.

[0043] The propulsion system 98 firstly comprises a turbomachine 102 comprising a low pressure body 104 and a high pressure body 103. The turbomachine 102 is for example a propulsion turbomachine of the aircraft.

[0044] The propulsion system 98 further comprises a power exchange installation 100.

[0045] The installation 100 comprises a voltage bus 160, as well as, for example, at least one electrical load 14, 15 connected to the voltage bus 160. Each load 14, 15 corresponds, for example, and in a non-limiting manner, to one or more pieces of equipment of the aircraft.

[0046] The installation 100 further comprises an electromechanical converter 150 BP , qualified as low pressure, designed to exchange power P BPbetween the voltage bus 160 and the low pressure body 104. Thus, the low pressure electromechanical converter 150 BP is for example designed, in a first power transfer direction, to take mechanical power from the low pressure body 104, in order to supply electrical power to the voltage bus 160. The low pressure electromechanical converter 150BP is further for example designed, in a second power transfer direction, to take electrical power from the voltage bus 160 in order to supply mechanical power to the low pressure body 104. To exchange the PBP power, an IBP current is thus exchanged between the voltage bus 160 and the low pressure electromechanical converter 150BP.

[0047] Similarly, for the high-pressure body 103, the installation 100 further comprises a 150HP electromechanical converter, described as high pressure, designed to exchange PHP power between the voltage bus 160 and the high-pressure body 103. Thus, the 150HP high-pressure electromechanical converter is for example designed, in a first direction of power transfer, to take mechanical power from the high-pressure body 103, in order to supply electrical power to the voltage bus 160. The high-pressure electromechanical converter 150 HP is further designed, for example, in a second direction of power transfer, to take electrical power from the voltage bus 160 in order to supply mechanical power to the high pressure body 103. To exchange the PHP power, an IHP current is thus exchanged between the voltage bus 160 and the high pressure electromechanical converter 150HP.

[0048] For example, each electromechanical converter 150 BP , 150 HP comprises an electric machine coupled to the low pressure body 104 or high pressure body 103, respectively, and an AC-DC converter configured to transfer electrical power between the voltage bus 160 and the electric machine. Thus, the electric machine can receive mechanical torque to generate an alternating current which is rectified by the AC-DC converter to provide the DC bus voltage V DC . The AC-DC converter can further convert the DC voltage V DC to supply alternating current to the electric machine so that the latter provides mechanical torque to inject power into the turbomachine 102.

[0049] The installation 100 further comprises, for each electromechanical converter 150 BP , 150 HP, a 125 voltage regulation module BP , 125 HP designed to regulate the bus voltage V DC at a voltage setpoint V DC * by ordering the 150 electromechanical converter BP , 150 HP considered in order to adjust its exchanged power PHP, PBP. The same voltage setpoint VDC* is thus received by the voltage regulation modules 125BP, 125HP.

[0050] Each voltage regulation module 125BP, 125HP comprises in particular a setpoint determination module 130HP, 130BP designed to determine an exchange setpoint, denoted GBP*, GHP*, of a physical quantity of the electromechanical converter 150BP, 150HP considered, in order to regulate the VDC bus voltage, this physical quantity being linked to the exchanged power PBP, PHP. Indeed, the injection of electrical power into the voltage bus 160 tends to increase the VDC bus voltage, while the withdrawal of electrical power from the voltage bus 160 tends to decrease the VDC bus voltage. Thus, by adjusting the exchange setpoint GBP*, GHP*, it is possible to modify the exchanged power PBP, PHP to ensure that the electromechanical converter 150BP, 150HP considered injects or draws more or less electrical power and therefore modifies the VDC bus voltage.

[0051] The exchange instruction GBP*, GHP* is, for example, a power instruction to be exchanged P BP *, P HP * by the electromechanical converter 150 BP , 150 HP considered. This is the case that will be developed later.

[0052] Alternatively, the GBP*, GHP* exchange instruction can be a current instruction I BP , I HP between the electromechanical converter 150 BP , 150 HP considered and the voltage bus 160. In fact, when the VDC* setpoint is constant, the VDC bus voltage which is regulated to this setpoint also remains substantially constant, so that the current I BP , I HP directly represents the exchanged power P BP , P HP ,.

[0053] Alternatively, the exchange instruction G BP *, G HP * can be a torque instruction of the electric machine.

[0054] Each of the 125 voltage regulator modules BP , 125 HP further includes a control module 140 BP , 140 HP designed to control the 150 low pressure electromechanical converter BP , respectively high pressure 150 HP , in order to regulate the physical quantity to its exchange setpoint G BP *, G HP *.

[0055] The installation 100 further comprises, for at least one of the electromechanical converters 150 BP , 150 HP , a 110 communication module BP , 110 HP and a 120 module BP , 120 HP compliance with sharing instructions. In the example illustrated, these two modules 110 BP , 110 HP and 120 BP , 120 HP are provided for each of the two electromechanical converters 150 BP , 150 HP .

[0056] The 110 communication module BP , 110 HPis designed to receive a sharing instruction S between the exchanged powers P HP , P BP , as well as an evaluation PBP°, PHP° of the power exchanged PBP, PHP by the other electromechanical converter 150BP, 150HP.

[0057] This evaluation PBP°, PHP° of the power exchanged PBP, PHP by the other electromechanical converter 150BP, 150HP can be, for example, the power setpoint to be exchanged PBP*, PHP* of the other of the electromechanical converters 150BP, 150HP.

[0058] Alternatively, this PBP°, PHP° evaluation can be, for example, a measure of the power exchanged PBP, PHP by the other of the electromechanical converters 150BP, 150HP.

[0059] From the data received by the communication module 110BP, 110HP, the module 120BP, 120HP is designed to adjust the power exchanged PBP, PHP by the electromechanical converter 150BP, 150HP considered in order to respect the sharing instruction S received, taking into account the received evaluation PBP°, PHP° of the power exchanged PBP, PHP by the other of the electromechanical converters 150BP, 150HP. For example, the module 120 BP , 120 HP is designed to regulate the exchange setpoint G BP *, GHP* of the 150BP electromechanical converter, 150HP considered, in order to respect the sharing instruction S. For this, the 120 module BP , 120 HP is for example designed for apply, in the voltage regulation module 130BP, 130HP, a voltage correction δVBP, δVHP to the voltage setpoint VDC*. Thus, the exchange setpoint GBP*, G HP * is determined by the voltage regulation module 130 BP , 130 HPbased on the voltage setpoint V DC * corrected by the voltage correction δV BP , δV HP . Thus, this voltage correction δVBP, δVHP makes it possible to modify the exchange instruction GBP*, G HP *, and therefore the exchanged power P BP , P HP .

[0060] Thus, the regulations of the bus voltage V DC implemented by the control of electromechanical converters 150 BP , 150 HP can be carried out independently of each other, while ensuring that the power sharing follows the S setpoint.

[0061] The 110 modules BP , 110 HP , 120 BP , 120 HP thus complement the 125 voltage regulation modules BP , 125 HP . The voltage setpoint V DC * is therefore defined independently of the power sharing regulation implemented by the 120 modules BP , 120 HP. For example, the voltage setpoint V DC * is provided by a calculator other than CL calculators HP , CL BP .

[0062] Still with reference to figure 1, the installation 100 may comprise independent local CLBP, CLHP computers, respectively associated with the low pressure electromechanical converter 150BP and the high pressure electromechanical converter 150HP.

[0063] Each local computer CLBP, CLHP thus implements at least the voltage regulation module 130BP, 130HP and the control module 140BP, 140HP of the associated electromechanical converter 150BP, 150HP. This allows a reduced number of computers to be used. Each local computer CLBP, CLHP can also implement the communication module 110BP, 110HP and the module 120BP, 120HP of the associated electromechanical converter 150BP, 150HP.

[0064] The installation 100 further comprises, for example, a central computer 106 designed to provide the sharing instruction S to each communication module 110HP, 110BP.

[0065] The central computer 106 is for example designed to determine the sharing setpoint S as a function of an operating point (measured and / or estimated, for example from other measurements) of the turbomachine 102. For example, and in a non-limiting manner, the operating point may comprise one or more of: the fuel inlet flow rate and / or the air inlet flow rate, a speed of rotation of the BP body 104, a rotation speed of the HP body 103, an air inlet temperature and / or fuel inlet temperature and / or exhaust gases leaving the combustion chamber.

[0066] Alternatively, the 110 modules BP , 120 BP , 110 HP , 120 HPcan be implemented in the central computer 106 and not in the local computers CL HP , CL BP .

[0067] The following description will develop an example of implementation in the particular case where the exchange instructions G BP *, G HP * are power instructions to be exchanged P BP *, P HP * and where the P evaluations BP °, P HP ° of the exchanged powers P BP , P HP are also the power instructions to be exchanged P BP *, P HP *.

[0068] Thus, Figure 2 reproduces the illustration of the propulsion system 98 of Figure 1 in this particular case.

[0069] Referring to Figure 3, the module 120 HP includes a 200 block HP calculation of a desired power setpoint to be exchanged P HP **, from the sharing instruction S and the power instruction to be exchanged P BP* (taken as P assessment BP ° of the exchanged power P BP ), in order to comply with the sharing instruction S.

[0070] For example, in a so-called proportional sharing mode, the sharing setpoint S can be in the form of a ratio, for example expressed as a percentage, between the exchanged powers PBP, PHP. In this case, the 200HP block is designed to determine the desired setpoint of power to be exchanged PHP** by multiplying or dividing the setpoint of power to be exchanged PBP* by the sharing setpoint S: PHP** = PBP* x S (when S = PHP / PBP) or PHP** = PBP* / S (when S = PBP / PHP).

[0071] Alternatively, the ratio can be between one of the exchanged powers PBP, PHP and the sum of the exchanged powers PBP, PHP. The ratio S is thus in the interval [0,1]. In this case, the desired setpoint of power to be exchanged PHP** can be calculated by the block 200HP by multiplying the sum of the exchange setpoints PBP* and PHP* (taken as evaluations PBP°, PBP° of the exchanged powers PBP, PHP) by the sharing setpoint S: PHP** = S x (PBP* + PHP*).

[0072] In a so-called differential sharing mode, the sharing setpoint S can be in the form of a difference between the exchanged powers PBP, PHP. In this case, the 200HP block is designed to determine the desired power setpoint to be exchanged P HP ** by adding or subtracting the sharing instruction S to the power instruction to be exchanged PBP* (taken as PBP° evaluation of the power exchanged PBP): PHP** = PBP* + S (when S = PHP - PBP) or PHP** = PBP* - S (when S = PBP - PHP).

[0073] It may be interesting for the sharing mode to change over time. Thus, to know this sharing mode and therefore the meaning of the sharing instruction S received, each communication module 110 BP , 110 HP may further be configured to receive a sharing mode indication identifying the sharing mode from among several predefined sharing modes which include for example at least one of the proportional mode and the differential mode presented above.

[0074] So, block 200 HP is designed to take into account the indication of the sharing mode in determining the desired power setpoint to be exchanged P HP **. For example, module 120 BP , 120 HPis designed to select the formula associated with the indicated sharing mode, this formula giving the desired power setpoint to be exchanged P HP ** from the sharing instruction S and the power instruction to be exchanged P BP * on the other side (taken as an evaluation of the exchanged power P BP on the other side). For example, the proportional sharing mode is associated with the formula P HP ** = P BP * x S (when S = P HP / P BP ) or P HP ** = P BP / S (when S = PBP / PHP) or PHP** = S x (PBP* + PHP* ) (when S = PHP / (PBP + PHP)), and the differential mode is associated with the formula PHP** = PBP* + S (when S = PHP - PBP) or PHP** = PBP* - S (when S = PBP - PHP).

[0075] The 120HP module further comprises a comparator 201HP designed to calculate an error εPHP* between the desired setpoint of power to be exchanged PHP** and the setpoint of power to be exchanged PHP*, and a corrector 202HP designed to calculate the voltage correction δVHP from the error εPHP*. Preferably, the corrector 202HP has zero static error. For example, the corrector 202HP is of the PI (proportional-integral) or PID (proportional-integral-derivative) type. The use of a corrector avoids the problems associated with the use of a resistance value in the patent application JP 2014131469 A discussed previously.

[0076] Similarly, with reference to Figure 4, the module 120BP comprises a block 200BP for calculating the desired power setpoint to be exchanged PBP** from the sharing setpoint S and the power setpoint to be exchanged PHP* (taken as evaluation P HP ° of the exchanged power P HPon the other side, a comparator 201BP designed to calculate an error εPBP* between the desired power setpoint to be exchanged PBP** and the power setpoint to be exchanged PBP*, and a corrector 202BP designed to calculate the voltage correction δV BP from the error εP BP *.

[0077] Referring to Figure 5, the 130HP setpoint determination module includes a 300HP comparator, designed to calculate a difference ΔVDC, HP between the voltage setpoint V DC * corrected for voltage correction δV HP, and the bus voltage V DC : ΔV DC, HP = V DC * - δV HP - V DC .

[0078] The 300 comparator HP can further be configured to calculate a difference ΔV 2 DC, HP between the square of the voltage setpoint V DC * corrected for voltage correction δV HP, and the square of the bus voltage V DC : ΔV 2DC, HP = (V DC * - δV HP ) 2 – V 2 DC .

[0079] The 130 setpoint determination module HP further includes a corrector 301 HP designed to determine the power setpoint to be exchanged P HP * from the difference ΔV DC, HP or ΔV 2 DC, HP . Preferably, corrector 301 HP is zero static error. For example, the 301 corrector HP is of type PI (proportional-integral) or PID (proportional-integral-derivative).

[0080] Similarly, with reference to FIG. 6, the setpoint determination module 130 BP includes a 300 comparator BP and a 301 corrector BP .

[0081] The presence of zero static error correctors in local CL computers BP , CL HP, could lead to a divergence in the power sharing, with one of the BP or HP electromechanical converters taking all the power. In order to control the power sharing between the BP and HP electromechanical converters, the central computer 106 sends sharing instructions to the local computers CLBP, CLHP of the 150BP, 150HP electromechanical converters. Each 150BP, 150HP electromechanical converter knowing its power and that of the other can then perform power balancing.

[0082] In order to stabilize the power exchanges of the installation 100, each communication module 110BP, 110HP is further designed to implement slow communications, for example and in a non-limiting manner at frequencies lower than 1kHz and preferably of the order of 1kHz, so that the balancing loop, formed by the local computers CLBP, CLHP communicating with each other, has a slower bandwidth than the voltage regulation loop, formed by each local computer CLBP, CLHP and the corresponding electromechanical converter.

[0083] The 110 communication module BP , 110 HP is further designed to implement slow communications, for example and not limited to frequencies lower than 1kHz and preferably of the order of 1kHz, between the central computer 106 and the local computers CLBP, CLHP.

[0084] The installation 100 is thus designed to be able to operate with a single active balancing law on the two (power and voltage balancing) which makes it possible to ensure redundancy in the event of loss of communication between the central computer 106 and the local computers CL BP , CL HP and / or a loss of communication between the local CL computers BP , CL HP .

[0085] Referring to Figure 7, the control module 140 HP includes for example a 400 block HP designed to determine a setpoint of at least one current of the electromechanical converter 150 HP , this or these currents defining the exchanged power P HP . For example, these are phase I currents A,HP , I B,HP , I C,HPfor example for three phases A, B, and C of the electric machine, expressed in a rotating frame provided with a direct axis and a quadrature axis by direct and quadrature currents. Thus, block 400 HP is for example designed to determine a direct current setpoint I D,HP * and a quadrature current setpoint I Q,HP *. This determination is for example carried out from an angular position θ HP and a rotation speed ωHP of a rotor of the electric machine and the bus voltage VDC.

[0086] The angular position θHP and the rotation speed ωHP of the rotor of the electric machine allow in particular to express the electrical quantities, such as the phase currents IA,HP, IB,HP, IC,HP, in the rotating reference frame. As for the bus voltage VDC, it allows to carry out the modulation of the phase currents IA,HP, IB,HP, IC,HP or to determine the direct current setpoint ID,HP* via a defluxing method.

[0087] The 140HP control module further comprises, for example, a 401HP current regulation block designed to provide commands to the 150HP high-pressure electromechanical converter from the current setpoint(s) ID,HP*, IQ,HP* and a measurement of this or these currents, for example, phase currents IA,HP, IB,HP, IC,HP. The commands are, for example, PWMHP pulse width modulation commands.

[0088] Similarly, with reference to Figure 8, the control module 140BP comprises for example a block 400 BP designed to determine a setpoint of at least one current of the 150BP low pressure electromechanical converter, this or these currents defining the exchanged power PBP. For example, these are phase I currents A,BP , I B,BP , I C,BP for three phases A, B, and C of the electric machine, expressed by direct and quadrature currents. Thus, the 400BP block is designed to determine a direct current setpoint ID,BP* and a quadrature current setpoint IQ,BP*. This determination is for example carried out from an angular position θ BP and a rotation speed ω BP of an electric machine rotor and VDC bus voltage.

[0089] The 140 control module BP further comprises, for example, a current regulation block 401 BPdesigned to provide commands to the 150 low pressure electromechanical converter BP from the current setpoint(s) I D,BP *, I Q,BP * and a measurement of this or these currents, for example phase I currents A,BP , I B,BP , I C,BP . The commands are for example PWM pulse width modulation commands BP .

[0090] With reference to FIG. 9, the installation 100 may further comprise, optionally, for the low pressure side and / or the high pressure side, a selection module 170. BP , 170 HP designed to directly receive a G' exchange instruction BP , G' HP , called direct, for example coming from the central computer 106, and to supply it selectively to the control module 140 BP , 140 HP, instead of the GBP*, GHP* exchange instruction provided by the 120BP, 120HP module. Thus, the power exchanged by the 150BP, 150HP electromechanical converter considered is directly regulated by the direct exchange instruction G'BP, G'HP.

[0091] In the example shown in Figure 9, only the 170HP selection module is activated.

[0092] On the side where the 170HP, 170BP selection module is activated, bus voltage regulation is no longer carried out. In this situation, voltage regulation of the VDC bus voltage is then carried out on the other side.

[0093] Figure 10 repeats Figure 9 in the particular case where the exchange instructions GBP*, GHP* are power instructions to be exchanged PBP*, PHP* and where the evaluations PBP°, PHP° of the exchanged powers PBP, PHP are also the power instructions to be exchanged PBP*, PHP*.

[0094] In this case, the 170BP, 170HP modules receive power instructions to be exchanged P'BP or P'HP.

[0095] The direct supply of the power setpoint to be exchanged P' BP or P' HP , without going through the calculation of a voltage correction, makes it possible to define the power exchanges in operating phases where the definition of the setpoint of power sharing S is not suitable, for example when one wishes the power exchange on one side to be fixed and the exchange on the other side to be arbitrary. In addition, the direct supply of the power setpoint to be exchanged P' BP or P' HP allows this instruction to be applied more quickly, which is useful, for example, in the event of assistance.

[0096] Figure 11 and Figure 12 illustrate a possible implementation of the modules 120 HP , 120 BPin the general case illustrated in Figure 1. Thus, in this example, the modules 200 BP , 200 HP are designed to calculate the desired power setpoint to be exchanged P BP **, P HP ** from the sharing instruction S, from the evaluation P BP °, P HP ° of the exchanged power P BP , P HP on the other side, and if necessary the P assessment BP °, P HP ° of the exchanged power P BP , P HP on the side considered. The 120 modules HP , 120 BP then also include an 1100 module BP , 1100 HP designed to calculate a desired exchange setpoint G BP **, G HP ** from the desired power setpoint to be exchanged P BP **, P HP **. The 201 comparators BP , 201 HP are then designed to calculate an error between the desired exchange instruction G BP **, G HP** and the exchange deposit G BP *, G HP *, and the correctors 202 BP , 202 HP (always preferably with zero static error) are designed to calculate the voltage correction δVBP, δVHP from the error.

[0097] With reference to Figure 13, in other embodiments, the regulation of the errors εPHP*, εPBP* of the instructions PHP*, PBP* can be replaced by a regulation of differences of these errors εPHP*, εPBP*.

[0098] Indeed, during transient changes on the bus (modification of electrical load), the VDC bus voltage drifts. However, with the regulation of the errors εPHP*, εPBP*, it is possible that a power change in the same direction (for example, an increase in the supplied power) is requested at the same time on the HP side and the LP side, but with the sharing remaining constant. Thus, the bus voltage can remain for a long time at a level different from the desired VDC* setpoint. By regulating instead the differences in the errors εPHP*, εPBP*, this undesirable side effect is avoided.

[0099] Thus, the 201HP comparator can be replaced by a 1302HP comparator designed to calculate the difference ΔεP HP * following between the errors εP HP *, εP BP * : ΔεPHP* = εPHP* – εPBP* = (PHP** – PHP*) – (PBP** – PBP*). Similarly, the 201BP comparator can be replaced by a 1302BP comparator designed for calculate the following difference ΔεPBP* between the errors εPHP*, εPBP*: ΔεPBP* = εPBP* – εPHP* = (PBP** – PBP*) – (PHP** – PHP*).

[0100] Figure 14 illustrates a possible implementation of the 120 modules HP , 120 BP in the general case illustrated in Figure 1, with ΔεG HP * and ΔεG BP * the following differences between εG errors HP *, εG BP * : ΔεG HP * = εG HP * – εG BP * = (G HP ** – G HP *) – (G BP ** – G BP *) and ΔεG BP * = εG BP * – εG HP * = (G BP ** – G BP *) – (G HP ** – G HP *).

[0101] The desired instructions G HP **, G BP ** are for example exchanged via the communication modules 100 HP , 110 BP .

[0102] In conclusion, it will be noted that the invention is not limited to the embodiments described above. It will indeed appear to those skilled in the art that various modifications can be made to the embodiments described above, in light of the teaching which has just been disclosed to them.

[0103] In the detailed presentation of the invention given above, the terms used should not be interpreted as limiting the invention to the embodiments set forth in this description, but should be interpreted to include all equivalents the prediction of which is within the reach of those skilled in the art by applying their general knowledge to the implementation of the teaching just disclosed to them.

Claims

Claims [1] Installation (100) for exchanging power in an aircraft, comprising: - a voltage bus (160) designed to have a bus voltage (VDC); - an electromechanical converter (150BP) called low pressure (BP) designed to exchange power (PBP) between the voltage bus (160) and a low pressure body (104) of a turbomachine (102) of the aircraft; - an electromechanical converter (150HP) called high pressure (HP) designed to exchange power (PHP) between the voltage bus (160) and a high pressure body (103) of the turbomachine (102) of the aircraft; and - for each electromechanical converter (150 BP , 150 HP ), a voltage regulation module (125 BP , 125 HP ), designed to regulate the bus voltage (V DC ) by controlling the electromechanical converter (150 BP , 150 HP ) considered in order to adjust the exchanged power (P HP , P BP) by the electromechanical converter (150 BP , 150 HP ) considered; characterized in that it further comprises: - a calculator (106) designed to provide a sharing instruction (S) between the exchanged powers (P HP , P BP ), this sharing instruction (S) varying over time; and - for at least one of the electromechanical converters (150 BP , 150 HP ): • a communication module (110 BP , 110 HP ) designed to receive the sharing instruction (S) provided by the calculator (106) and an evaluation (P BP °, P HP °) of the exchanged power (P BP , P HP ) by the other of the electromechanical converters (150 BP , 150 HP ), and • a module (120 BP , 120 HP ) of respect for the sharing instruction (S), designed to adjust the exchanged power (P HP , P BP ) by the electromechanical converter (150 BP , 150HP ) considered in order to respect the sharing instruction (S) received, taking into account the evaluation (P BP °, P HP °) received from the exchanged power (P BP , P HP ) by the other of the electromechanical converters (150 BP , 150 HP ). [2] Power exchange installation (100) according to claim 1, in which the module (120BP, 120HP) for respecting the sharing instruction (S) is designed to adjust the power exchanged (PBP, PHP) by the electromechanical converter (150BP, 150HP) in question by modifying a voltage instruction (VDC*) so that the module voltage regulation (125BP, 125HP) of the electromechanical converter (150BP, 150HP) in question regulates the bus voltage (VDC) to the modified bus voltage. [3] Power exchange installation (100) according to claim 2, in which the module (120 BP , 120 HP) of compliance with the sharing instruction (S) is designed to apply, in the voltage regulation module (125 BP , 125 HP ), a voltage correction (δV BP , δV HP ) to the voltage setpoint (V DC *). [4] Power exchange installation (100) according to any one of claims 1 to 3, in which each voltage regulation module (125 HP , 125 BP ) includes: - a setpoint determination module (130 HP , 130 BP ) designed to determine an exchange instruction (G BP *, G HP *) for the electromechanical converter (150 BP , 150 HP ) considered; and - a control module (140 BP , 140 HP ) designed to control the electromechanical converter (150 BP , 150 HP ) considered, so that the electromechanical converter (150 BP , 150 HP ) considered respects the exchange instruction (G BP *, GHP*). [5] Power exchange installation (100) according to claim 4, in which the exchange instruction (GBP*, GHP*) is a power instruction to be exchanged (PBP*, PHP*) between the electromechanical converter (150BP, 150HP) in question and the voltage bus (160). [6] Power exchange installation (100) according to claim 4, in which the exchange instruction (GBP*, GHP*) is a current instruction to be exchanged between the electromechanical converter (150BP, 150HP) in question and the voltage bus (160) or else, the electromechanical converters (150BP, 150HP) each comprising an electrical machine coupled to the associated body (103, 104), the exchange instruction (GBP*, GHP*) is a torque instruction of the electrical machine.[7] Power exchange installation (100) according to any one of claims 4 to 6, in which the module (120BP, 120HP) for respecting the sharing instruction (S) is designed to: - determine a desired exchange instruction (GBP**, GHP**) in order to respect the sharing instruction (S) received taking into account the evaluation. (PBP°, PHP°) received from the exchanged power (PBP, PHP) by the other of the electromechanical converters (150BP, 150HP); and - regulate the exchange setpoint (G BP *, G HP *) of the electromechanical converter (150 BP , 150 HP ) considered at the desired exchange setpoint (GBP**, GHP**). [8] Power exchange installation (100) according to claims 3 and 7, in which the module (120 BP , 120 HP ) of compliance with the sharing instruction (S) includes: - a comparator (201 BP , 201 HP ) designed to calculate an error between the desired exchange setpoint (G BP**, G HP **) and the exchange deposit (G BP *, G HP *); and - a corrector (202 BP , 202 HP ) designed to calculate the voltage correction (δV BP , δV HP ) from the error. [9] Power exchange installation (100) according to any one of claims 4 to 6, in which the module (120 BP , 120 HP ) of compliance with the sharing instruction (S) is designed to determine a desired exchange instruction (G BP **, G HP**) in order to respect the sharing instruction (S) received taking into account the evaluation (PBP°, PHP°) received from the exchanged power (PBP, PHP) by the other of the electromechanical converters (150BP, 150HP), and comprises: - a comparator (1302BP, 1302HP) designed to calculate a difference (ΔεGBP*, ΔεGHP*) between, on the one hand, an error (εGBP*, εGHP*) between the desired exchange instruction (GBP**, GHP**) and the exchange instruction (GBP*, GHP*) of the electromechanical converter considered (150BP, 150HP) and, on the other hand, an error (εGHP*, εGBP*) between the desired exchange instruction (GBP**, GHP**) and the exchange instruction (GBP*, GHP*) of the other converter electromechanical (150BP, 150HP); and - a corrector (202BP, 202HP) designed to calculate the voltage correction (δVBP, δVHP) from the difference (ΔεGBP*, ΔεGHP*). [10] Power exchange installation (100) according to claim 8 or 9, wherein the corrector (202BP, 202HP) has zero static error.[11] Power exchange installation (100) according to any one of claims 7 to 10, in which the communication module (110. BP , 110 HP ) is further adapted to receive a sharing mode indication from among several predefined sharing modes, and wherein the module (120 BP , 120 HP ) of respect for the sharing setpoint (S) is further designed to determine the desired exchange setpoint (GBP**, GHP**) from the received sharing mode indication. [12] Power exchange installation (100) according to claim 11, in which the predefined sharing modes comprise at least one of: - a proportional sharing mode, in which the received power sharing setpoint (S) is a ratio between the exchanged powers (P BP , P HP ) and in which the module (120 BP , 120 HP) of compliance with the sharing instruction (S) is designed to determine the desired exchange instruction (G BP **, G HP **) by multiplying or dividing the evaluation (P BP °, P HP °) received by the sharing instruction (S); and - a differential sharing mode, in which the power sharing instruction (S) received is a difference between the exchanged powers (P BP , P HP ), and in which the module (120 BP , 120 HP ) of compliance with the sharing instruction (S) is designed to determine the desired exchange instruction (G BP **, G HP **) by adding the evaluation (P BP °, P HP °) received at the sharing instruction (S) or by subtracting the evaluation (P BP °, P HP°) received from the sharing instruction (S). [13] Power exchange installation (100) according to any one of claims 4 to 12, further comprising a selection module (170BP, 170HP) designed to provide, on command, an exchange instruction (G'BP, G'HP), called direct, to the control module (140BP, 140HP) of the electromechanical converter (150BP, 150HP) in question, instead of the exchange instruction (GBP*, GHP*), so that the power exchanged (PBP, PHP) by the electromechanical converter (150BP, 150HP) in question is regulated to the direct exchange instruction (G'BP, G'HP). [14] Power exchange installation (100) according to any one of claims 4 to 13, in which the exchange instructions (GBP*, GHP*) are power instructions to be exchanged (PBP*, PHP*).[15] Power exchange installation (100) according to claim 14, in which the evaluation (PBP°, PHP°) of the power exchanged (PBP, PHP) by the other of the electromechanical converters (150BP, 150HP) is the power setpoint to be exchanged (P. BP *, P HP *) of the other electromechanical converters (150 BP , 150 HP ). [16] Power exchange installation (100) according to any one of claims 1 to 15, in which the evaluation (PBP°, PHP°) of the exchanged power (P BP , P HP ) by the other of the electromechanical converters (150 BP , 150 HP ) is a measure of the exchanged power (P HP , P BP) by the other of the electromechanical converters (150BP, 150HP). [17] Propulsion system (98) of an aircraft comprising a turbomachine (102) and an installation (100) according to any one of claims 1 to 16. [18] Aircraft comprising a propulsion system (98) according to claim 17. [19] Method of exchanging power in an aircraft, characterized in that it comprises: - for each of an electromechanical converter (150 BP ) called low pressure (LP) and an electromechanical converter (150 HP ) called high pressure (HP), the low pressure electromechanical converter (150 BP ) being designed to exchange power (P BP ) between a voltage bus (160) adapted to have a bus voltage (V DC) and a low pressure body (104) of a turbomachine (102) of the aircraft, the high pressure electromechanical converter (150HP) being designed to exchange power (PHP) between the voltage bus (160) and a high pressure body (103) of the turbomachine (102) of the aircraft, a regulation of the bus voltage (VDC) by controlling the electromechanical converter (150BP, 150HP) in question in order to adjust the exchanged power (PBP, PHP); - a supply by a computer (106) of a sharing setpoint (S) between the exchanged powers (PHP, PBP), this sharing setpoint (S) varying over time;and - for at least one of the electromechanical converters (150BP, 150HP): • a reception of the sharing instruction (S) provided by the computer (106) and of an evaluation (PBP°, PHP°) of the power exchanged (PBP, PHP) by the other of the electromechanical converters (150BP, 150HP), and • an adjustment of the power exchanged (PHP, PBP) by the electromechanical converter (150BP, 150HP) considered in order to respect the sharing instruction (S) received, taking into account the evaluation (PBP°, PHP°) received of the power exchanged (PBP, PHP) by the other of the electromechanical converters (150BP, 150HP).; [20] Computer program downloadable from a communication network and / or recorded on a computer-readable medium, characterized in that it comprises instructions for executing the steps of a power exchange method in an aircraft according to the preceding claim, when said program is executed on a computer.

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