Electrical system for an aircraft equipped with an engine

Abstract

This disclosure relates to an aircraft electrical system (4) (100) comprising: a first bus (411); a second bus (412); a first generator (401); a first converter (421); a second generator (402); and a second converter (422). Figure for the abstract: Fig. 3

Description

Title of the invention: Electrical system for an aircraft equipped with an engine FIELD OF THE INVENTION

[0001] The present application relates to the aeronautical field. More specifically, the present application relates to the electrical power supply of an aircraft equipped with an engine. STATE OF THE ART

[0002] An aircraft may include electrical loads, such as a de-icing system or a pressurization module for a cabin of the aircraft, as well as an alternating current network and a direct current network, which are intended in particular to supply these loads with electrical energy. The electrical power circulating on these networks is generally produced by rotating bodies of the aircraft engine. In this case, the electrical production must be able to be distributed between the rotating bodies. Under certain conditions, it is necessary that these rotating bodies be able to receive electrical power, typically to be started and / or to be assisted in flight. These constraints must not, however, increase the mass or reduce the efficiency of the engine. Statement of the invention

[0003] An aim of the invention is to improve the electrical system for supplying an aircraft with electrical energy from the rotating bodies of its engine.

[0004] To this end, according to one aspect of the present disclosure, there is provided an electrical system for aircraft comprising: a first bus intended to be connected to an alternating current network of an aircraft to allow a transfer of electrical power from the first bus to the alternating current network; a second bus intended to be connected to a direct current network of the aircraft to allow a transfer of electrical power from the second bus to the direct current network; a first electrical generator connected to the first bus to inject or take electrical power from the first bus, the first electrical generator being designed to be connected to a first rotating body of an engine of the aircraft to allow an exchange of mechanical and / or electrical power between the first rotating body and the first electrical generator; a first alternating current to direct current converter, the first converter being connected to the first bus to inject or take electrical power from the first bus and to the second bus to inject or take a electrical power on the second bus; a second electrical generator intended to be connected to a second rotating body of the aircraft engine to allow an exchange of mechanical and / or electrical power between the second rotating body and the second electrical generator; and a second alternating current to direct current converter, the second converter being connected to the second electrical generator to allow an exchange of electrical power between the second electrical generator and the second converter, and to the second bus to inject or take electrical power from the second bus.

[0005] Advantageously, but optionally, the electrical system according to the present disclosure may comprise at least one of the characteristics, taken alone or in combination: - it also includes: a third bus intended to be connected to the alternating current network to enable a transfer of electrical power from the third bus to the alternating current network; a third electrical generator connected to the third bus for injecting or drawing electrical power from the third bus, the third electrical generator being designed to be connected to the first rotating body to allow an exchange of mechanical and / or electrical power between the first rotating body and the third electrical generator; a third alternating current to direct current converter, the third converter being connected to the third bus for injecting or drawing electrical power from the third bus and to the second bus for injecting or drawing electrical power from the second bus; a fourth electrical generator intended to be connected to the second rotating body to allow an exchange of mechanical and / or electrical power between the second rotating body and the fourth electrical generator; and a fourth alternating current to direct current converter, the fourth converter being connected to the fourth electrical generator to allow an exchange of electrical power between the fourth electrical generator and the fourth converter and to the second bus to inject or take electrical power from the second bus; - the third electric generator is configured to provide voltage regulation of the third bus; - the first electrical generator is configured to provide voltage regulation of the first bus; - at least one of the converters is configured to operate according to at least one of the following operating modes: a forced mode, in which the converter ensures the power regulation of at least one bus to which it is connected; a free mode, in which the converter ensures voltage regulation of the second bus; - it further comprises a controller configured to control at least one of the converters so as to determine its operating mode; and - the first electrical generator is connected to the controller and configured to receive an instruction from the controller to ensure power regulation of the first bus.

[0006] According to another aspect of the present disclosure, there is provided an aircraft comprising: an engine comprising a first rotating body and a second rotating body; an alternating current network; a direct current network; and an electrical system as previously described, in which the first bus is connected to the alternating current network, the second bus is connected to the direct current network, the first electrical generator and / or the third electrical generator is connected to the first rotating body, and the second electrical generator and / or the fourth electrical generator is connected to the second rotating body.

[0007] Advantageously, but optionally, the aircraft according to the present disclosure may comprise at least one of the characteristics, taken alone or in combination: - the first rotating body is a high pressure body and the second rotating body is a low pressure body; and - the first rotating body is a low pressure body and the second rotating body is a high pressure body.

[0008] According to another aspect of the present disclosure, there is provided a method of controlling an electrical system as previously described, the method being implemented by the controller and comprising: controlling the second converter so that it operates in free mode to ensure voltage regulation of the second bus; receiving a first measurement of electrical power injected by the first electrical generator on the first bus; receiving a second measurement of electrical power exchanged between the second electrical generator and the second converter; comparing a ratio between the first measurement and the second measurement with a reference value; and the control of the first converter so that, if the ratio is different from the reference value, it operates in a forced mode in which it regulates in power the first bus.

[0009] According to another aspect of the present disclosure, there is provided another method of controlling an electrical system as previously described, the method being implemented by the controller and comprising: receiving a measurement of electrical power injected by the first electrical generator on the first bus; comparison of the measurement with a reference value; controlling the first converter so that, if the measurement is different from the reference value, it operates in a forced mode in which it regulates the power of the first bus; and controlling the second converter so that it operates in free mode to ensure voltage regulation of the second bus.

[0010] According to another aspect of the present disclosure, there is provided another method of controlling an electrical system as previously described, the method being implemented by the controller and comprising: receiving a measurement of electrical power exchanged between the second electrical generator and the second converter; the comparison of the measurement with a reference value; and controlling the second converter so that, if the measurement is different from the reference value, it operates in a forced mode in which it regulates the power of the second bus; and controlling the first converter so that it operates in free mode to ensure voltage regulation of the second bus.

[0011] Advantageously, but optionally, one of the other control methods according to the present disclosure may further comprise a step of controlling the first electrical generator so that it regulates the voltage of the first bus.

[0012] According to another aspect of the present disclosure, there is provided yet another method of controlling an electrical system as previously described, the method being implemented by the controller and comprising: receiving a measurement of electrical power injected by the first electrical generator on the first bus; comparison of the measurement with a reference value; controlling the first electric generator so that, if the first measurement is different from the first reference value, it regulates the power of the first bus; controlling the first converter so that it operates in free mode to ensure voltage regulation of the first bus and the second converter so that it operates in free mode to ensure voltage regulation of the second bus.

[0013] According to another aspect of the present disclosure, there is provided another method of controlling an electrical system as previously described, the method being implemented by the controller and comprising: receiving a measurement of electrical power exchanged between the second electrical generator and the second converter; comparison of the measurement with a reference value; controlling the second converter so that, if the measurement is different from the reference value, it operates in a forced mode in which it regulates the power of the second bus; receiving a measurement of electrical power injected by the first electrical generator on the first bus; comparison of the measurement with a reference value; controlling the first converter so that, if the measurement is different from the reference value, it operates in a forced mode in which it regulates the power of the first bus; and controlling an electrical source connected to the second bus so that the electrical source regulates the voltage of the second bus.

[0014] According to another aspect of the present disclosure, there is provided a computer program comprising instructions which, when the program is executed by a computer of the controller, cause the latter to implement the control method according to any one of the previously described implementation modes.

[0015] According to another aspect of the present disclosure, there is provided a computer-readable medium comprising instructions which, when executed by a computer of the controller, cause the latter to implement the control method according to any of the previously described implementation modes. DESCRIPTION OF FIGURES

[0016] Other characteristics, aims and advantages of the present disclosure will emerge from the following description, which is purely illustrative and not limiting, and which must be read in conjunction with the appended drawings in which:

[0017] [Fig.l] illustrates an aircraft schematically.

[0018] [Fig.2] is a schematic sectional view of an aircraft propulsion unit.

[0019] [Fig. 3] schematically illustrates an electrical system according to one aspect of the present disclosure.

[0020] [Fig.4] is a more detailed illustration of [Fig.3].

[0021] [Fig.5] schematically illustrates an electrical system according to another aspect of the present disclosure.

[0022] [Fig.6] is a flowchart illustrating one aspect of a first variant of a control method according to the present disclosure.

[0023] [Fig.7] is a flowchart illustrating another aspect of the first variant of the control method according to the present disclosure.

[0024] [Fig.8] is a flowchart illustrating another aspect of the first variant of the control method according to the present disclosure.

[0025] [Fig.9] is a flowchart illustrating one aspect of a second variant of a control method according to the present disclosure.

[0026] Throughout the figures, similar elements bear identical references. DETAILED DESCRIPTION OF THE INVENTION Aircraft

[0027] [Fig.l] illustrates an aircraft 100 comprising at least one propulsion unit 1, in this case two propulsion units 1. The aircraft 100 shown is an airplane, civil or military, but could be any other type of aircraft 100, such as a helicopter. The propulsion units 1 are attached and fixed to the airplane 100, each under a wing of the airplane 100, as visible in [Fig.l]. This is not, however, limiting, since at least one propulsion unit 1 can also be mounted on the wing of the airplane or at the rear of its fuselage.

[0028] The aircraft 100 also comprises a plurality of electrical loads (or receivers) (not shown). Each electrical load is a device powered by electrical energy and can be configured to transform the electrical energy that supplies it into another form of energy, such as for example heat or mechanical energy. Non-limiting examples of electrical loads of the aircraft 100 are: an electric motor, a heating and / or air conditioning system, a compressor, etc. These electrical loads make it possible in particular to ensure a certain number of functionalities, in flight as well as on the ground, such as the pressurization and / or illumination of the cabin of the aircraft 100, the operation of the cockpit, etc.

[0029] To supply these electrical loads with electrical energy, the aircraft 100 comprises a plurality of electrical networks, including at least one alternating current network 43_AC and one direct current network 44_DC, illustrated from [Fig. 3] to [Fig. 4]. Each electrical network 43_AC, 44_DC typically comprises a set of electrical conductors, typically a set of wire(s) or bar(s) and / or an assembly of wire(s) and / or one (or more) printed track(s) and / or some device which is used to conduct electricity. The alternating current network 43_AC only allows the circulation of electrical energy in the form of an alternating signal, while the direct current network 44_DC only allows the circulation of electrical energy in the form of a direct signal.

[0030] The electrical energy consumed by the electrical loads can, at least in part, be produced by the engine 2 of the propulsion unit 1, and more precisely by means of rotating bodies 20, 22, 26 of the engine 2. Propulsion unit

[0031] [Fig.2] illustrates a propulsion unit 1 having a longitudinal axis XX, and comprising an engine 2 (or turbomachine) and a nacelle 3 surrounding the engine 2.

[0032] The propulsion assembly 1 is intended to be mounted on an aircraft 100, for example in the manner illustrated in [Fig.l]. In this regard, the propulsion assembly 1 may comprise a mast (not shown) intended to connect the propulsion assembly 1 to a part of the aircraft 100.

[0033] The engine 2 illustrated in [Fig. 2] is a twin-spool, twin-flow, direct-drive turbojet engine. This is not, however, limiting since the engine 2 may have a different number of spools and / or flows, and / or be another type of turbojet engine, such as a geared turbojet engine or a turboprop engine.

[0034] Unless otherwise specified, the terms “upstream” and “downstream” are used with reference to the overall direction of airflow through the propulsion unit 1 in operation. Similarly, an axial direction corresponds to the direction of the longitudinal axis XX and a radial direction is a direction perpendicular to the longitudinal axis XX and intersecting the longitudinal axis XX. Furthermore, an axial plane is a plane containing the longitudinal axis XX and a radial plane is a plane perpendicular to the longitudinal axis XX. A circumference is understood to be a circle belonging to a radial plane and whose center belongs to the longitudinal axis XX. A tangential or circumferential direction is a direction tangent to a circumference: it is perpendicular to the longitudinal axis XX but does not pass through the longitudinal axis XX.Finally, the adjectives "inner" (or "internal") and "outer" (or "external") are used with reference to a radial direction so that the inner part of an element is, in a radial direction, closer to the longitudinal axis XX than the outer part of the same element.

[0035] As visible in [Fig.2], the engine 2 comprises, from upstream to downstream, a fan 20, a compression section 22 comprising a low pressure compressor 220 and a high pressure compressor 222, a combustion chamber 24 and an expansion section 26 comprising a high pressure turbine 262 and a low pressure turbine 260. The fan 20, the rotor part of the low pressure compressor 220, and the rotor part of the low pressure turbine 260 are connected together by a low pressure shaft 280 extending along the longitudinal axis XX, the fan 20, the low pressure compressor 220 and the low pressure turbine 260 then forming a low pressure body 20, 220, 260 (LP body), 280, which is a first rotating body. The rotor part of the high pressure compressor 222 and the rotor part of the high pressure turbine 262 are connected to each other by a high-pressure shaft 282 extending along the longitudinal axis XX, the high-pressure compressor 222 and the high-pressure turbine 262 then forming a high-pressure body 222, 262, 282 (HP body), which is a second rotating body. As visible in [Fig. 2], the compression section 22, the combustion chamber 24 and the expansion section 26 are surrounded by a motor casing 23, while the fan 20 is surrounded by a fan casing 25. The motor casing 23 and the fan casing 25 are connected to each other by profiled structural arms 27 forming rectifiers (or OGV for "Outlet Guide Vanes" in English terminology) distributed circumferentially all around the longitudinal axis XX.The longitudinal axis XX forms the axis of rotation for the fan 20, the rotor part of the compression section 22 and the rotor part of the expansion section 26, in other words for the first rotating body and the second rotating body, which are capable of being driven in rotation around the longitudinal axis XX relative to the engine casing 23 and the fan casing 25.

[0036] The nacelle 3 extends radially outside the engine 2, all around the longitudinal axis XX, so as to surround both the fan casing 25 and the engine casing 23, and to define, with a downstream portion of the engine casing 23, a downstream portion of a secondary duct B, the upstream portion of the secondary duct B being defined by the fan casing 25 and an upstream portion of the engine casing 23. The upstream portion of the nacelle 3 further defines an air inlet 29 through which the fan 20 sucks in the air flow circulating through the propulsion unit 1. The nacelle 3 is integral with the fan casing 25 and attached and fixed to the aircraft 100 by means of the mast.

[0037] The engine 2 may also comprise at least one accessory box (not shown), called AGB (for “Accessory gear box” in English terminology), typically housed in a cavity provided within the nacelle 3. The accessory box comprises a set of gears making it possible to drive a plurality of shafts in rotation around their own axis, accessories being mounted on these shafts to derive useful mechanical power from their rotation. The gear assembly is itself driven using a power take-off shaft connecting, possibly via a transfer case (not shown), the accessory case to at least one of the high pressure body 222, 262, 282 and the low pressure body 20, 220, 260, 280, typically by being meshed with at least one of the high pressure shaft 282 and the low pressure shaft 280.In this regard, the power take-off shaft may extend inside a longitudinal cavity provided within one of the structural arms 27. In this manner, mechanical power may be taken from at least one of the high pressure body 222, 262, 282 and the low pressure body 20, 220, 260, 280 to be delivered to at least one of the accessories via the accessory housing.

[0038] The motor 2 may also comprise a plurality of electrical loads (not shown), such as a starter or a battery, which must also be supplied with electrical energy, some in the form of an alternating signal, others in the form of a continuous signal.

[0039] In operation, the fan 20 draws in an air flow, a portion of which, circulating within a primary vein A, is successively compressed within the compression section 22, ignited within the combustion chamber 24 and expanded within the expansion section 26 before being ejected from the engine 2. The primary vein A passes through the engine casing 23 from one side to the other. Another portion of the air flow circulates within the secondary vein B which takes an elongated annular shape surrounding the engine casing 23, the air drawn in by the fan 20 being straightened by the straighteners and then ejected from the propulsion unit 1. In this way, the propulsion unit 1 generates thrust. This thrust can, for example, be used for the benefit of the aircraft 100 on which the propulsion unit 1 is attached and fixed. Electrical system

[0040] [Fig. 3] illustrates an electrical system 4 distributed between the propulsion unit 1 and the aircraft 100 for supplying electrical energy to the electrical loads of the engine 2 and / or the aircraft 100, typically by means of the alternating current network 43_AC and the direct current network 44_DC.

[0041] The electrical system 4 comprises a first bus 411_AC connected to the alternating current network 43_AC to allow a transfer of electrical power from the first bus 411_AC to the alternating current network 43_AC. The first bus 411_AC is therefore configured to allow a flow of electrical energy in the form of an alternating signal. The electrical system 4 further comprises a second bus 412_DC connected to the direct current network 44_DC to allow a transfer of electrical power from the second bus 412_DC to the direct current network 44_DC. The second bus 412_DC is therefore configured to allow a flow of electrical energy in the form of a direct signal. Each of the first bus 411_AC and the second bus 412_DC typically comprises a set of electrical conductors, typically a set of wire(s) or bar(s) and / or an assembly of wire(s) and / or one (or more) printed track(s) and / or some device that serves to conduct electricity.The electrical loads of the motor 2 can also be connected to at least one of the first bus 411_AC and the second bus 412_DC to withdraw the electrical energy necessary for their operation.

[0042] The electrical system 4 further comprises a first electrical generator 401 connected to the first bus 411_AC to inject or take electrical power from the first bus 411_AC. The first electrical generator 401 is, moreover, connected to a rotating body 20, 22, 26 of the engine 2 to allow an exchange of power mechanical and / or electrical power between the rotating body 20, 22, 26 and the first electrical generator 401. In addition, the electrical system 4 comprises a second electrical generator 402 connected to another rotating body 20, 22, 26 of the engine 2 to allow an exchange of mechanical and / or electrical power between the other rotating body 20, 22, 26 and the second electrical generator 402.

[0043] Each of the first electric generator 401 and the second electric generator 402 may typically be a wound rotor synchronous machine, typically comprising three stages, called VFG (for “Variable Frequency Generator” in English terminology), driven by at least one of the high pressure shaft 282 and the low pressure shaft 280 of the motor 2, typically via the accessory box. Such a machine has the advantage in particular of being able to be controlled to regulate the voltage of the bus to which it is connected. Typically, when the first electric generator 401 is a VFG type machine, the first electric generator 401 can then control the voltage of the first bus 411_AC according to a predetermined voltage, typically 115Vac or 230Vac, depending, in particular, on the quality constraints of the alternating current network 43_AC.This is not, however, limiting since other types of machines are conceivable, such as permanent magnet synchronous machines, called PMSM (for “Permanent-Magnet Synchronous Machine Drives” in English terminology) which have the advantage of having a smaller mass, or such as asynchronous machines (or “Induction machine” in English terminology) or variable reluctance machines. Preferably, the first electric generator 401 is a VFG type synchronous machine, while the second electric generator 402 is a PMSM type permanent magnet synchronous machine.

[0044] Each of the first electric generator 401 and the second electric generator 402 is therefore connected to a rotating body 20, 22, 26 separate from the motor 2. Thus, in a variant shown from [Fig. 3] to [Fig. 5], the first electric generator 401 is connected to the high-pressure body 222, 262, 282 and the second electric generator 402 is connected to the low-pressure body 20, 220, 260, 280. In another variant (not shown), the first electric generator is connected to the low-pressure body and the second electric generator is connected to the high-pressure body. Each of the first electric generator 401 and the second electric generator 402 can therefore operate as an electric motor, when it draws electrical power from the first bus 411_AC and / or the second bus 412_DC to transmit mechanical power to the rotating body 20, 22, 26 to which it is connected.Furthermore, each of the first electric generator 401 and the second electric generator 402 can operate as an electric generator, when it injects an electric power on the first bus 411_AC and / or on the second bus 412_DC which it has transformed from a power. mechanical extracted on the rotating body 20, 22, 26 to which it is connected.

[0045] As seen in [Fig.3], the first electrical generator 401 may comprise a control device 4010 configured to control the alternating voltage generated by the first electrical generator 401 on the first bus 411_AC.

[0046] [Fig. 3] also illustrates that the electrical system 4 comprises a first alternating current to direct current converter 421, which is connected both to the first bus 411_AC, to inject or take electrical power from the first bus 411_AC, and to the second bus 412_DC, to inject or take electrical power from the second bus 412_DC. The first converter 421 is reversible and allows a portion of the electrical power generated by the first electrical generator 401 to be transferred from the first bus 411_AC to the second bus 412_DC. The first converter 421 also allows electrical power to be transferred from the second bus 412_DC to the first bus 411_AC to provide electrical power to the first electrical generator 401.The first electric generator 401 can thus transform this electric power received from the second bus 412_DC into mechanical power for the benefit of the rotating body 20, 22, 26 to which it is connected. As will be described in more detail below, this can typically take place when starting the engine 2 or during an assistance phase of the engine 2.

[0047] [Fig. 3] finally illustrates that the electrical system 4 comprises a second alternating current to direct current converter 422, which is connected both to the second electrical generator 402 to allow an exchange of electrical power between the second electrical generator 402 and the second converter 422, and to the second bus 412_DC to inject or take electrical power from the second bus 412_DC. By controlling the second converter 422, it is therefore possible to inject or take mechanical power at the rotating body 20, 22, 26 to which the second electrical generator 402 is connected.

[0048] Each of the first converter 421 and the second converter 422 can take the form of an inverter or a rectifier, controlled or not.

[0049] [Fig.4] illustrates the electrical system 4 in more detail.

[0050] As visible in [Fig. 4], each of the first converter 421 and the second converter 422 comprises a control device 4210, 4220, while the electrical system 4 comprises a controller 45 configured to control each of the first converter 421 and the second converter 422, preferably via their control device 4210, 4220. In practice, the controller 45 may be a controller 45 of the motor 2, which controls the control devices 4210, 4220 by means of control references (in current, power, torque, etc.). The controller 45 comprises a processor (not shown) configured to implement at least one aspect of at least one of the variants of the control method E, E', E”, E'” of the electrical system 4 described in more detail from [Fig.6] to [Fig.9]. The processor of the controller 45 is adapted to read a computer-readable medium comprising instructions which, when executed by a computer such as the processor of the controller 45, cause the latter to implement the control method E, E', E”, E'”. The computer-readable medium and / or the controller 45 are configured to load, typically into a memory, a computer program comprising instructions which, when the program is executed by a computer such as the processor of the controller 45, cause the latter to implement the control method E, E', E”, E'”. In this regard, the controller 45 may comprise a memory (not shown).

[0051] In operation, it is necessary to ensure different regulations of the electrical system 4.

[0052] The power regulation of the first bus 411_AC and / or of the second bus 412_DC makes it possible to ensure that the electrical power transmitted to the first bus 411_AC and / or to the second bus 412_DC by the first electrical generator 401 and / or the second electrical generator 402 is sufficient to meet the demand of the electrical loads of the aircraft 100 and / or of the engine 2 on the alternating current network 43_AC and / or on the direct current network 44_DC.

[0053] In a first variant, as will be described in more detail below with reference to [Fig.6], [Fig.7] and [Fig.8], during operation of the electrical system 4, the power regulation of the first bus 411_AC and / or of the second bus 412_DC is implemented by at least one of the first converter 421 and the second converter 422.

[0054] In a second variant, also described in more detail below with reference to [Fig.9], the first electric generator 401 can be configured to receive an instruction from the controller 45, which allows it to regulate the power of the first bus 411-AC.

[0055] The voltage regulation of the first bus 411_AC and / or the second bus 412_DC is critical. Indeed, the temporal evolution of the electrical voltage within the first bus 411_AC and / or the second bus 412_DC, during the operation of the electrical system 4, must remain within the limits of a template even if, of course, it can occasionally vary around a given nominal value. Indeed, for all the elements which are connected to the first bus 411_AC and / or to the second bus 412_DC to function correctly, the electrical voltage must not take values ​​which exceed the limits of the template. The template defines, in fact, the upper and lower limits of excursion of the electrical voltage, as a function of time, during the operation of the electrical system 4. The template may comprise limits defined for normal and / or abnormal operating conditions, which limits surround, symmetrically or not, a nominal electrical voltage level of the first bus 411_AC and / or the second bus 412_DC. In a diagram (not shown) providing the evolution of the electrical voltage as a function of time, a limit of a template is typically represented as a line, broken or not. Preferably, even if the limit does not define a constant electrical voltage value at first, generally associated with the characteristic time of start-up (or startup) of the electrical system 4, it is common for the limit to then define a constant electrical voltage value, in order to guarantee the stability of operation of the first bus 411_AC and / or the second bus 412_DC and, therefore, of the electrical system 4.Such a template may, for example, be defined in a standard relating to the quality of the electrical system 4 and / or the alternating current network 43_AC and / or the direct current network 44_DC, but also be defined by specifications of a device to which the electrical system 4 is connected, typically the requirements of the manufacturer of the aircraft 100 within which the electrical system 4 is integrated.

[0056] In this regard, and as will be described in detail below, during operation of the system 4 according to the first variant, the voltage regulation of the first bus 411_AC is advantageously implemented by the first electrical generator 401, in particular when it is a synchronous machine of the VFG type. In addition, the voltage regulation of the second bus 412_DC is advantageously implemented by at least one of the first converter 421 and the second converter 422, except when starting the motor 2, where this voltage regulation cannot be ensured by the converters 421, 422 and where, as will be described in more detail below, it is necessary for another electrical source to be connected to the second bus 412_AC to ensure the voltage regulation thereof.

[0057] As will be described in more detail below, in the second variant in which it is the first electric generator 401 which ensures the power regulation of the first bus 411_AC, it is the first converter 421 which ensures the voltage regulation of the first bus 411_AC and the second converter 422 which ensures the voltage regulation of the second bus 412_AC.

[0058] Thus, each of the first converter 421 and the second converter 422 is configured to operate in various operating modes.

[0059] In a forced mode, the converter 421, 422 injects or draws electrical power, which is set by the controller 45, on the first bus 411_AC and / or the second bus 412_DC, depending on certain operating parameters of the motor 2, as will be described in more detail below. In other words, in the forced mode, the converter 421, 422 ensures the power regulation of the bus(es) 411_AC, 412_DC to which it is connected.

[0060] In the first variant, in a free mode, the converter 421, 422 injects or takes electrical power from the first bus 411_AC and / or from the second bus 412_DC which depends on the electrical power transferred to the alternating current network 43_AC and / or the direct current network 44_DC, and on the voltage of the first bus 411_AC and / or the second bus 412_DC. More precisely, in the first variant, the converter 421, 422 ensures, in the free mode, the voltage regulation at least of the second bus 412_DC.

[0061] In the second variant in which it is the first electric generator 401 which ensures the power regulation of the first bus 411_AC, the converters 421, 422 are, in the free mode, configured to regulate the voltage of the first bus 411_AC and the second bus 412_DC.

[0062] In a standby mode, the converter 421, 422 is not in operation, and does not transfer or draw any power from the first bus 411_AC and / or the second bus 412_DC.

[0063] The controller 45 is therefore configured to control the first converter 421 and / or the second converter 422 so as to determine its operating mode, but also the associated setpoint (generation or assistance, as described in detail below). Typically, the controller 45 can receive a measurement of the power exchanged between the first electric generator 401 and the rotating body 20, 22, 26 to which it is connected, which can typically be provided by the control device 4010 of the first electric generator 401, and a measurement of the power exchanged between the second electric generator 402 and the rotating body 20, 22, 26 to which it is connected, which can typically be provided by the control device 4220 of the second converter 422.From these measurements, the controller 45 can calculate the control references to be transmitted to the control devices 4210, 4220 of the converters 421, 422 determining a forced mode and the level of fixed electrical power that they must take and / or inject on the first bus 411_AC and / or the second bus 412_DC.

[0064] [Fig.5] illustrates an electrical system 4 according to another embodiment, similar to the embodiment illustrated in [Fig.3] and in [Fig.4].

[0065] As visible in [Fig.5], in this embodiment, the electrical system 4 further comprises a third bus 413_AC connected to the alternating current network 43_AC to allow a transfer of electrical power from the third bus 413_AC to the alternating current network 43_AC. The third bus 413_AC advantageously has a structure and operation identical to the first bus 411-AC.

[0066] Furthermore, the electrical system 4 also comprises a third electrical generator 403 connected to the third bus 413_AC to inject or take electrical power from the third bus 413_AC, the third electrical generator 403 being connected to the same rotating body 20, 22, 26 as the first electric generator 401, to allow an exchange of mechanical and / or electrical power between this rotating body and the third electric generator 403. The third electric generator 403 preferably has a structure and operation identical to the first electric generator 401. In particular, in the first variant, the voltage regulation of the third bus 413_AC is advantageously implemented by the third electric generator 403, typically when it is a synchronous machine of the VFG type. In the second variant, the third electric generator 403 can be configured to receive a setpoint from the controller 45, which allows it to regulate the power of the third bus 413_AC.

[0067] In addition, the electrical system 4 comprises a third alternating current to direct current converter 423, the third converter 423 being, on the one hand, connected to the third bus 413_AC, to inject or take electrical power from the third bus 413_AC and, on the other hand, to the second bus 412_DC, to inject or take electrical power from the second bus 412_DC. The third converter 423 advantageously has a structure and operation identical to the first converter 421. Just like the first converter 421, the third converter 423 may comprise a control device (not shown) configured to control the alternating voltage generated by the third electrical generator 403 on the third bus 413_AC.

[0068] Furthermore, as visible in [Fig.5], the electrical system 4 comprises a fourth electrical generator 404 connected to the same rotating body 20, 22, 26 as the second electrical generator 402, to allow an exchange of mechanical and / or electrical power between this rotating body and the fourth electrical generator 404. The fourth electrical generator 404 preferably has a structure and operation identical to the second electrical generator 402.

[0069] Finally, the electrical system 4 comprises a fourth alternating current to direct current converter 424, the fourth converter 424 being, on the one hand, connected to the fourth electrical generator 404, to allow an exchange of electrical power between the fourth electrical generator 404 and the fourth converter 424 and, on the other hand, to the second bus 412_DC, to inject or take electrical power from the second bus 412_DC. The fourth converter 424 preferably has a structure and operation identical to the second converter 422.

[0070] Each of the third converter 423 and the fourth converter 424 may also comprise a control device (not shown), and operate according to the operating modes described for the first converter 421 and the second converter 422, in particular, in forced mode, for the power regulation of the third bus 413_AC and / or the second bus 412_DC by injection and / or sampling of an electrical power fixed on the third bus 413_AC and / or the second bus 412_DC, or, in free mode, for the voltage regulation of the second bus 412_DC, and, in the second variant in which it is the first electrical generator 401 which ensures the power regulation of the first bus 411_AC and / or it is the third electrical generator 403 which ensures the power regulation of the third bus 413_AC, for the voltage regulation of the third bus 413_AC. Where appropriate, the controller 45 is configured to control one of the third converter 423 and the fourth converter 424 so as to determine its operating mode.

[0071] Thanks to the electrical system 4 according to one of the embodiments described, a transfer of power is made possible between the rotating bodies 20, 22, 26, in particular via the first bus 411_AC and / or the second bus 412_DC and / or the third bus 413_AC.

[0072] It should further be noted that, when the aircraft 100 is equipped with two engines 2, this aircraft 100 may comprise one electrical system 4 per engine 2. Where appropriate, each electrical system 4 may be connected to an alternating current network 43_AC and / or a direct current network 44_DC which is distinct, or not, from the other electrical system 4. This advantageously makes it possible to benefit from redundancy between the electrical systems of each of the engines 2. Control process

[0073] From [Fig.6] to [Fig.8], different aspects of the first variant of a method of controlling E, E', E” an electrical system 4 according to at least one of the embodiments described are shown. Each time, the method of controlling E, E', E” is implemented by the controller 45, possibly assisted by the control devices 4010 and / or the control devices 4210, 4220. These different aspects correspond to different situations, during the operation of the aircraft 100, on the ground as well as in flight, during which the electrical system 4 is used to ensure the exchanges of power between the engine 2 and the aircraft 100.

[0074] With reference to [Fig. 6], the electrical system 4 is used to power the electrical loads of the aircraft 100 and / or the engine 2, while respecting a distribution of the electrical power generated from the high and low pressure bodies 20, 22, 26 of the engine 2 that the controller 45 imposes on it. More precisely, the second converter 422 is controlled E1 so as to operate in a free mode, thus ensuring the voltage regulation of the second bus 412_DC. In addition, a first measurement ml of an electrical power injected by the first electrical generator 401 on the first bus 411_AC and a second measurement m2 of an electrical power exchanged between the second electrical generator 402 and the second converter 422 are received E2, E3 then, a ratio ml / m2 between the first measurement and the second measurement is compared E4 to a reference value, typically the value imposed by the controller 45 for the distribution of power to be taken from each of the high and low pressure bodies 20, 22, 26. Finally, if the ratio is different from the reference value, the first converter 421 is controlled E5 so as to operate in a forced mode of power regulation of the first bus 411_AC in which it injects or takes a fixed electrical power from the first bus 411_AC. In other words, the controller 45 continuously adapts the control reference of the first converter 421 so as to respect a predetermined distribution of the electrical power generated by the first electrical generator 401 and the second electrical generator 402. Advantageously, the voltage of the first bus 411_AC is, for its part, regulated by the first electrical generator 401, in particular when the latter is a synchronous machine of the VFG type.

[0075] With reference to [Fig.7], the electrical system 4 is used to assist the rotating body 20, 22, 26 (preferably the HP body) connected to the first electrical generator 401. More precisely, to assist the rotating body 20, 22, 26 connected to the first electric generator 401, a measurement ml' of an electric power injected by the first electric generator 401 on the first bus 411_AC is received E'1 and compared E'2 to a reference value, which is typically the power requested to assist the rotating body 20, 22, 26 to which the first electric generator 401 is connected. If the measurement ml' is different from the reference value, the first converter 421 is controlled E'3 so as to operate in a forced mode in which it regulates the power of the first bus 411_AC, that is to say that it injects or it takes a fixed electric power on the first bus 411_AC.Furthermore, the second converter 422 is then controlled E'4 so as to operate in a free mode, thus ensuring the voltage regulation of the second bus 412_DC. Advantageously, the voltage of the first bus 411_AC is, for its part, regulated by the first electric generator 401, in particular when the latter is a synchronous machine of the VFG type.

[0076] With reference to [Fig. 8], the electrical system 4 is used to assist the rotating body 20, 22, 26 (preferably the BP body) connected to the second electrical generator 402. More precisely, a measurement m2” of an electrical power exchanged between the second electrical generator 402 and the second converter 422 is received E”1 and compared E”2 to a reference value, which is typically the power requested to assist the rotating body 20, 22, 26 to which the second electrical generator 402 is connected. If the measurement m2” is different from the reference value, the second converter 422 is controlled E”3 so as to operate in a forced mode in which it regulates the power of the second bus 412_DC, that is to say that it injects or it takes a fixed electrical power on the second bus 412_DC. Furthermore, the first converter 421 is controlled E”4 so as to operate in a free mode, as it thus ensures the voltage regulation of the second bus 412_DC. Advantageously, the voltage of the first bus 411_AC is, for its part, regulated by the first electric generator 401, in particular when the latter is a synchronous machine of the VFG type.

[0077] In other words, the controller 45 continuously adapts the control reference of the first converter 421 and / or the second converter 422 so as to assist the rotating bodies 20, 22, 26 by means of the first electric generator 401 and / or the second electric generator 402, while ensuring the voltage regulation of the second bus 412_DC, the voltage regulation of the first bus 411_AC being, for its part, advantageously ensured by the first electric generator 401, in particular when the latter is a synchronous machine of the VFG type.

[0078] Of course, it is possible to assist both the rotating body 20, 22, 26 connected to the first electric generator 401 and the rotating body 20, 22, 26 connected to the second electric generator 402, for example when starting the engine 2. To do this, the steps illustrated in [Fig.7] to [Fig.8] are carried out in parallel, each of the first converter 421 and the second converter 422 being in forced mode. In this case, it is necessary for another electrical source (not shown) connected to the second bus 412_DC to ensure the voltage regulation of the second bus 412_DC. Furthermore, when only one or other of the rotating bodies 20, 22, 26 of the engine 2 needs to be started, typically the high pressure body 222, 262, 282, the corresponding converter 421, 422, 423, 424 may be in forced mode, while the other converter 421, 422, 423, 424 is in standby mode.

[0079] Table 1 below summarizes the different aspects of the control method E, E', E”. Generation by HP and BP bodies (figure 6) Assistance from HP body (figure 7) Assistance from BP body (figure 8) AC bus voltage regulation First electric generator 401 First electric generator 401 First electric generator 401 DC bus voltage regulation Second converter 422 (free mode) Second converter 422 (free mode) First converter 421 (free mode) AC bus power regulation First converter 421 (forced mode) First converter 421 (forced mode) - DC bus power regulation - - Second converter 422 (forced mode)

[0080] In a second variant illustrated in [Fig.9], the electrical system 4 is also used E'” to assist the rotating body 20, 22, 26 (preferably the HP body) connected to the first electrical generator 401, but this time using the capacity of the first electrical generation 401 to receive a setpoint from the controller 45 to regulate the power of the first bus 411_AC. Here again, a measurement ml'” of an electrical power injected by the first electrical generator 401 on the first bus 411_AC is received E'”l, this time by the first electrical generator 401, which compares E'”2 this measurement ml'” to a reference value, which is typically the power requested to assist the rotating body 20, 22, 26 (preferably the HP body) to which the first electrical generator 401 is connected and which the controller 45 will have transmitted to it.And, if the measurement ml'” is different from the reference value, it is indeed the first electrical generator 401, and no longer the first converter 421 as in the first variant of the control method E, E', E”, which is controlled E'”3 so as to regulate the power of the first bus 411_AC, that is to say to inject or take a fixed electrical power on the first bus 411_AC. Furthermore, each of the first converter 421 and the second converter 422 is then controlled E'”4 so as to operate in a free mode allowing them to ensure the voltage regulation, respectively, of the first bus 411_AC and the second bus 412_DC. Advantages obtained.

[0081] The electrical system and control method described make it possible to generate, distribute and control mixed power for supplying electrical loads of the aircraft and / or the engine which operate on both alternating current and direct current, while taking into account the constraints of the engine both when it generates power or when it must be assisted.

[0082] In fact, thanks to the presence and control of the converters, the electric motors / generators of the electrical system are not only used to supply these electrical loads. Indeed, they also make it possible to optimize the operation of the motor, whether at the time of its start-up or during an assistance phase, according to the constraints specific to it, in particular in terms of power distribution between the rotating bodies. In addition, the converters make it possible to regulate the voltage of the buses of the electrical systems, and more particularly of the direct current bus, which guarantees stability and improves the safety of the electrical system in operation.

[0083] Furthermore, thanks to the electrical system and the control method described, it is not necessary to provide electrical converters and / or generators which would be dedicated to electrical loads operating on alternating current, or to electrical loads operating on direct current, which makes it possible to reduce the mass of the motor. Furthermore, even with the addition of electrical loads operating on direct current to the usual alternating current networks, it is possible to keep these usual alternating current networks, which have the advantage of being of mature technology, without having to add dedicated conversion elements to power them from the direct current networks. Finally, this ensures a dissimilarity at the aircraft level between alternating current networks and direct current networks from which the aircraft manufacturer can benefit.

[0084] Thus, the electrical system according to one of the embodiments described can adapt to any type of demand from the direct current network and / or the alternating current network, which makes it possible to respond to the trend of increased electrification of aircraft.

Claims

Claims

1. Electrical system (4) for aircraft (100) comprising: a first bus (411_AC) intended to be connected to an alternating current network (43_AC) of an aircraft (100) to allow a transfer of electrical power from the first bus (411_AC) to the alternating current network (43_AC); a second bus (412_DC) intended to be connected to a direct current network (44_DC) of the aircraft (100) to allow a transfer of electrical power from the second bus (412_DC) to the direct current network (44_DC); a first electrical generator (401) connected to the first bus (411_AC) for injecting or drawing electrical power from the first bus (411_AC), the first electrical generator (401) being designed to be connected to a first rotating body (20, 22, 26) of an engine of the aircraft (100) to allow an exchange of mechanical and / or electrical power between the first rotating body (20, 22, 26) and the first electrical generator (401); a first alternating current to direct current converter (421), the first converter (421) being connected to the first bus (411_AC) to inject or take electrical power from the first bus (411_AC) and to the second bus (412_DC) to inject or take electrical power from the second bus (412_DC); a second electrical generator (402) intended to be connected to a second rotating body (20, 22, 26) of the aircraft engine (100) to allow an exchange of mechanical and / or electrical power between the second rotating body (20, 22, 26) and the second electrical generator (402); and a second alternating current to direct current converter (422), the second converter (422) being connected to the second electric generator (402) to allow an exchange of electric power between the second electric generator (402) and the second converter (422), and to the second bus (412_DC) to inject or take electric power from the second bus (412_DC); wherein at least one of the converters (421, 422, 423, 424) is configured to operate according to at least one of the following operating modes: a forced mode, in which the converter (421, 422, 423, 424) ensures the power regulation of at least one bus (411_AC, 412_DC, 413_AC) to which it is connected; a free mode, in which the converter (421, 422, 423, 424) ensures the voltage regulation of the second bus (412_DC).

2. An electrical system (4) according to claim 1, further comprising: a third bus (413_AC) adapted to be connected to the alternating current network (43_AC) to enable a transfer of electrical power from the third bus (413_AC) to the alternating current network (43_AC); a third electrical generator (403) connected to the third bus (413_AC) to inject or take electrical power from the third bus (413_AC), the third electrical generator (403) being adapted to be connected to the first rotating body (20, 22, 26) to enable an exchange of mechanical and / or electrical power between the first rotating body (20, 22, 26) and the third electrical generator (403);a third alternating current to direct current converter (423), the third converter (423) being connected to the third bus (413_AC) to inject or take electrical power from the third bus (413_AC) and to the second bus (412_DC) to inject or take electrical power from the second bus (412_DC); a fourth electrical generator (404) intended to be connected to the second rotating body (20, 22, 26) to allow an exchange of mechanical and / or electrical power between the second rotating body (20, 22, 26) and the fourth electrical generator (404); and a fourth alternating current to direct current converter (424), the fourth converter (424) being connected to the fourth electrical generator (404) to allow an exchange of electrical power between the fourth electrical generator (404) and the fourth converter (424) and to the second bus (412_DC) to inject or take electrical power from the second bus (412_DC).;

3. Electrical system (4) according to claim 2, wherein the third electrical generator (403) is configured to provide voltage regulation of the third bus (413_AC).

4. Electrical system (4) according to one of claims 1 to 3, wherein the first electrical generator (401) is configured to provide voltage regulation of the first bus (411_AC).

5. Electrical system (4) according to one of claims 1 to 4, further comprising a controller (45) configured to control at least one of the converters (421, 422, 423, 424) so ​​as to determine its mode of functioning.

6. Electrical system (4) according to claim 5, wherein the first electrical generator (401) is connected to the controller (45) and configured to receive from the controller (45) an instruction to ensure power regulation of the first bus (411_AC).

7. An aircraft (100) comprising: an engine comprising a first rotating body (20, 22, 26) and a second rotating body (20, 22, 26); an alternating current network (43_AC); a direct current network (44_DC); and an electrical system (4) according to one of claims 1 to 6, wherein the first bus (411_AC) is connected to the alternating current network (43_AC), the second bus (412_DC) is connected to the direct current network (44_DC), the first electrical generator (401) and / or the third electrical generator (403) is connected to the first rotating body (20, 22, 26), and the second electrical generator (402) and / or the fourth electrical generator (404) is connected to the second rotating body (20, 22, 26).

8. The aircraft (100) of claim 7, wherein the first rotating body (20, 22, 26) is a high pressure body (222, 262, 282) and the second rotating body (20, 22, 26) is a low pressure body (20, 220, 260, 280).

9. An aircraft (100) according to claim 7, wherein the first rotating body (20, 22, 26) is a low pressure body (20, 220, 260, 280) and the second rotating body (20, 22, 26) is a high pressure body (222, 262, 282).

10. Method for controlling (E) an electrical system (4) according to claim 5, the method being implemented by the controller (45) and comprising: the control (El) of the second converter (422) so that it operates in free mode to ensure the voltage regulation of the second bus (412_DC); the reception (E2) of a first measurement (ml) of an electrical power injected by the first electrical generator (401) on the first bus (411_AC); the reception (E3) of a second measurement (m2) of an electrical power exchanged between the second electrical generator (402) and the second converter (422); the comparison (E4) of a ratio (ml / m2) between the first measurement (ml) and the second measurement (m2) with a reference value; and the control (E5) of the first converter (421) so that, if the ratio is different from the reference value, it operates in a forced mode in which it regulates the power of the first bus (411_AC).

11. Method for controlling (E') an electrical system (4) according to claim 5, the method being implemented by the controller (45) and comprising: receiving (E' 1) a measurement (ml') of an electrical power injected by the first electrical generator (401) on the first bus (411_AC); comparing (E'2) the measurement (ml') with a reference value; controlling (E'3) the first converter (421) so that, if the measurement (ml') is different from the reference value, it operates in a forced mode in which it regulates the power of the first bus (411_AC); and controlling (E'4) the second converter (422) so that it operates in free mode to ensure the voltage regulation of the second bus (412_DC).

12. Method for controlling (E”) an electrical system (4) according to claim 5, the method being implemented by the controller (45) and comprising: receiving (E”l) a measurement (m2”) of an electrical power exchanged between the second electrical generator (402) and the second converter (422); comparing (E”2) the measurement (m2”) with a reference value; and controlling (E”3) the second converter (422) so that, if the measurement (m2”) is different from the reference value, it operates in a forced mode in which it regulates the power of the second bus (412-DC); and controlling (E”4) the first converter (421) so that it operates in free mode to ensure the voltage regulation of the second bus (412_DC).

13. Control method (E', E'”) according to one of claims 11 and 12, further comprising a step of controlling the first electric generator (401) so that it regulates the voltage of the first bus (411_AC).

14. Method for controlling (E'”) an electrical system (4) according to claim 6, the method being implemented by the controller (45) and comprising: receiving (E'” 1) a measurement (ml'”) of an electrical power injected by the first electrical generator (401) on the first bus (411_AC); comparing (E'”2) the measurement (ml'”) with a reference value; controlling (E'”3) the first electrical generator (401) so that, if the first measurement is different from the first reference value, it regulates the power of the first bus (411_AC); controlling (E'”4) the first converter (421) so that it operates in free mode to ensure the voltage regulation of the first bus (411_AC) and the second converter (422) so that it operates in free mode to ensure the voltage regulation of the second bus (412_DC).

15. Computer program comprising instructions which, when the program is executed by a computer of the controller (45), cause the latter to implement the method (E, E', E”, E'”) according to one of claims 10 to 14.

16. A computer-readable medium comprising instructions which, when executed by a computer of the controller (45), cause the latter to implement the method (E, E', E”, E'”) according to one of claims 10 to 14.

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