System and method for generating electricity for an aircraft following detection of a fault

Abstract

Disclosed is a system (1) for generating electricity with a view to supplying power to at least one electrical network of an aircraft (REA), comprising converters (C1, C2), each converter (C1, C2) being configured to detect an internal fault, switch from a nominal mode (M1) to a fault mode (M3) in the event of detection of an internal fault, communicate its operating mode (M1-M3) to the at least one other converter (C1, C2), and switch directly from an auxiliary regulation (RegA) to a voltage regulation (RegU) on receipt of a fault mode (M3) from at least one other converter (C1, C2).

Description

System and method for generating electrical power for aircraft following fault detection

[0001] The present invention relates to an electrical generation system for an aircraft and, more generally, an electrical hybridization system for an aircraft.

[0002] Climate change is a major concern for many legislative and regulatory bodies worldwide. Indeed, various restrictions on carbon emissions have been, are being, or will be adopted by different countries. In particular, an ambitious standard applies to both new types of aircraft and those already in operation, requiring the implementation of technological solutions to bring them into compliance with current regulations. Civil aviation has been actively working for several years now to contribute to the fight against climate change.

[0003] Technological research efforts have already led to very significant improvements in the environmental performance of aircraft. The Applicant takes into account the factors impacting all phases of design and development in order to obtain less energy-intensive and more environmentally friendly aeronautical components and products whose integration and use in civil aviation have moderate environmental consequences, with the aim of improving aircraft energy efficiency.

[0004] This sustained research and development work focuses in particular on new generations of hybrid thermal and electric aircraft engines. The Applicant's objective is, among other things, to develop aircraft incorporating a high-power electrical generation system. This would increase the proportion of electrical equipment on board in order to reduce fuel consumption.

[0005] In practice, in a conventional aircraft turbomachine, it is known to integrate an electric generator which takes mechanical energy from the low-pressure shaft of the aircraft turbomachine to produce electrical energy which is distributed to an electrical power distribution unit.

[0006] To increase electrical power generation, a power generation system 100 has been proposed. This system is configured to extract mechanical energy from a low-pressure shaft (LP) and a high-pressure shaft (HP) of an aircraft turbomachine (T) to supply an aircraft electrical network (REA) with a calibrated distribution voltage. In other words, the power generation system 100 has at least two power supply paths: one LP path and one HP path. The power generation system 100 can also be connected to electrical sources (BAT) or electrical loads (LOAD), such as propulsion motors.

[0007] In practice, the electrical generation system 100 is configured to receive an operating setpoint P ECUThis information comes from the turbomachine T's ECU monitoring computer, which knows the status of each electrical source as well as the electrical requirements. This operating instruction P ECU allows us to determine, for example, the amount of electrical power to be generated, the mechanical load on each shaft, etc. In other words, the operating setpoint P ECU allows us to determine the chosen hybridization strategy. The operating instruction P ECU It also allows the configuration of the electrical generation system 100 to be modified in case of a fault, as will be shown later.

[0008] With reference to the diagram, the electrical generation system 100 comprises at least two generators G1, G2 (electrical sources) connected respectively to the low-pressure shaft BP and the high-pressure shaft HP of the turbomachine T. The electrical generation system 100 further comprises two converters C1, C2, specifically inverters, which are respectively associated with the two generators G1, G2. Each generator G1, G2 generates an alternating current which is then rectified by its converter C1, C2 to provide a distribution voltage V DC to an electrical distribution unit (EDU) which is electrically connected to the aircraft's electrical network (REA), to the electrical sources (BAT), or to the electrical loads (LOAD). Converters C1 and C2 are connected to the electrical distribution unit (EDU) by power cables H1 and H2.

[0009] This example presents an application related to electrical generation, but the invention applies more generally to the field of hybridization in which an electrical machine performs, on the one hand, a generator function to draw mechanical power from the low-pressure shaft (LP) or the high-pressure shaft (HP) and, on the other hand, a motor function to inject mechanical power onto the low-pressure shaft (LP) or the high-pressure shaft (HP). For the motor function, each converter C1, C2 can also convert the DC voltage V DC to supply alternating current to the two electrical machines G1, G2 respectively in order to inject power.

[0010] For the sake of clarity and conciseness, only the generator function is presented. For a motor function, the ECU provides an operating command P ECUallowing, for example, the determination of the mechanical power injection on each shaft, etc. The hybrid system is bidirectional to allow the generation of electrical power as well as the injection of mechanical power. The ECU (Engine Control Unit) provides overall supervision by determining an operating setpoint P ECU which is a function of the availability and capacity of electrical sources but also of the needs of electrical loads.

[0011] As is known, each converter C1, C2 contains a plurality of switches, specifically power transistors, which allow modification of the electrical power generated and the electrical power drawn by each generator G1, G2 on each shaft BP, HP. With reference to the operating setpoint P ECU includes P configuration instructions CONS1 , P CONS2for converters C1, C2 in order to obtain a distribution voltage V DC that is suitable for the EDU electrical distribution unit.

[0012] As is known, each converter C1, C2 is configured to receive parameterization instructions P CONS1 , P CONS2 of several types: A voltage regulation setpoint RegU configured to control converter C1, C2 according to a distribution voltage setpoint V DC * An auxiliary control setpoint RegA configured to control the converter C1, C2 to a power setpoint or a torque setpoint of the aircraft turbomachine T.

[0013] Preferably, the distribution voltage setpoint V DC * is predetermined and known to each converter C1, C2.

[0014] The operating instruction P ECUdetermines the type of regulation of each converter C1, C2 by determining the parameter setting P CONS1 , P CONS2 .

[0015] In practice, the ECU monitoring computer is connected to each converter C1, C2 by one or more communication cables (point-to-point or multi-subscriber link) to communicate the parameter setting instructions P CONS1 , P CONS2 but also to obtain data or measurements necessary for monitoring. Such communication cables, particularly of the CAN type, allow communication approximately every 15ms, which is slow.

[0016] As previously mentioned, the ECU also allows for modification of the electrical generation system 100 configuration in case of a fault. To this end, the ECU measures currents and voltages in the electrical generation system 100 to detect a fault, specifically a short circuit in a control device 200, a converter C1 or C2, or a power cable H1 or H2. As is known, converters C1 and C2 periodically send their operating mode to the ECU.

[0017] The electrical generation system 100 also includes multiple switches for isolating one or more devices. The ECU (Electrical Control Unit) controls these switches to reconfigure the electrical generation system 100, electrically isolating a power supply channel V1 or V2 in case of a fault. Thus, the ECU acts as a centralized supervisor, firstly determining the location and nature of the fault, and secondly, controlling the optimal configuration for isolating it.

[0018] One drawback is that such an ECU monitoring computer is relatively slow, on the order of 15 ms. In practice, the reconfiguration time, which allows the ECU monitoring computer to identify a fault and initiate the reconfiguration, is longer than the maximum permissible interruption time of the electrical generation system. This is because the electrical generation system must not be interrupted for extended periods, especially when it powers electric propulsion motors. An immediate solution would be to use an ECU monitoring computer with protocols that allow for higher-speed communication and greater computing power to more quickly identify faults and initiate the necessary reconfiguration. However, such an ECU monitoring computer is expensive and requires extensive modifications to the electrical generation system, which is a significant disadvantage.

[0019] Furthermore, when the first converter C1 detects an internal fault, it switches from a nominal mode to a fault mode in which the first converter C1 is no longer active. To become active again, the first converter C1 must undergo extensive maintenance, particularly upon the aircraft's return to the ground. In practice, when the internal fault of the first converter C1 occurs, it affects the entire electrical generation system 100, and the second converter C2 also detects a fault and switches from a nominal mode to a safety mode in which the second converter C2 limits its operation (degraded operation).

[0020] One of the objectives of the present invention is to enable the rapid reconfiguration of an electrical generation system without the need for a sophisticated supervisory control computer. PRESENTATION OF THE INVENTION

[0021] The invention relates to an electrical generation system for supplying at least one electrical network of an aircraft, hereinafter referred to as the aircraft network, the aircraft comprising at least one aircraft turbomachine including a low-pressure shaft and a high-pressure shaft configured to be driven in rotation, the electrical generation system comprising at least: A first power supply path comprising: A first generator configured to generate alternating current by drawing mechanical energy from one of the low-pressure and high-pressure shafts, A first converter, associated with the first generator to supply the aircraft network via at least one first power cable, A second power supply path comprising: A second generator configured to generate alternating current by drawing mechanical energy from the other of the low-pressure and high-pressure shafts, A second converter,associated with the second generator to supply the aircraft network via at least one second power cable, the electrical generation system being configured to receive a first parameter setting for the first converter and a second parameter setting for the second converter, each parameter setting being either a voltage regulation setting to control the converter to a distribution voltage setting or an auxiliary regulation setting, at least one of the parameter settings being a voltage regulation setting.

[0022] The electrical generation system is remarkable in that each converter is configured to: detect an internal fault, switch from a nominal mode to a fault mode upon detection of an internal fault, communicate its operating mode to the other converter, and switch directly from auxiliary regulation to voltage regulation upon receiving a fault mode from at least one other converter.

[0023] Advantageously, a voltage-regulating converter ensures the quality of the distribution voltage. An auxiliary voltage regulator assists the aircraft power system by supporting the distribution voltage. This allows it to meet load requirements, for example, from propulsion engines or a temporary overload of the aircraft power system.

[0024] Thanks to the invention, the power generation system can reconfigure itself autonomously without the supervisory computer. Thus, a converter in auxiliary regulation mode can automatically switch to voltage regulation mode in the event of a failure of another converter, in particular, a voltage-regulating converter.

[0025] This allows for a highly responsive system and prevents excessively long interruptions in power generation, which could impact aircraft flight. Advantageously, the converters communicate directly or indirectly via a power generation system control device and are configured to directly change their regulation mode. A standard supervisory computer with conventional computing resources can thus be retained to manage overall monitoring during flight. Fault management is handled locally by the converters themselves and the control device. Thanks to this invention, any degradation of the distribution voltage over time, which could lead to fault propagation, is effectively prevented. The power generation system is therefore more reliable and robust.

[0026] Preferably, the electrical generation system includes a control device connected to each converter by at least one communication cable so as to know the state of each converter but also data from each converter (input / output current, input / output voltage, etc.).

[0027] The control device is connected to a set of switches in such a way as to electrically isolate each converter.

[0028] Preferably, the communication cable is a discrete signal communication cable.

[0029] The control device is configured to electrically isolate the converter exhibiting the fault mode. Thus, the control device allows the fault related to the converter exhibiting the fault mode to be contained.

[0030] Preferably, each converter is configured to switch directly from auxiliary regulation to voltage regulation upon receiving a fault mode from at least one other converter and when the converter experiencing the fault mode has been electrically isolated. This ensures that any switchover is performed safely.

[0031] The control device offers a superior alternative to a supervisory computer for switching between different control modes to address a fault while remaining highly responsive. Unlike a supervisory computer, the control device only provides a local view.

[0032] According to one aspect, the converters are directly connected to each other by at least one communication cable, preferably with a confirmation time of less than 5ms.

[0033] The invention has been presented for at least two supply paths, but it is understood that the number of paths could be greater.

[0034] In one aspect, each converter is configured to directly communicate its operating mode to the control device, particularly when it enters fault mode. The control device is configured to electrically isolate the converter with the internal fault.

[0035] According to one aspect, the control device is connected to each converter by at least one communication cable, preferably with a confirmation time of less than 5ms.

[0036] Thus, electrical safety is ensured to allow degraded operation with a reduced number of equipment.

[0037] According to one aspect, the control device is configured to: detect a cable fault in a power cable, and electrically isolate the power cable having the cable fault.

[0038] Thus, a power cable can be reactively isolated without the need for a monitoring computer. In a preferred configuration, the converter associated with the faulty power cable is also isolated.

[0039] In one aspect, since each converter is in a safety mode following the detection of a cable fault, the converter not connected to the power cable with the fault is configured to switch directly from auxiliary regulation to voltage regulation after the electrical isolation of the fault. Thus, control is regained quickly.

[0040] Preferably, the converter, which is not connected to the power cable with the cable fault, is configured to switch to normal operation after the fault has been cleared. A cleared fault is one that has been located and electrically isolated from the rest of the system but remains present in an isolated portion of the power generation system.

[0041] Thus, voltage regulation can also be implemented for a cable fault without using the supervisory computer.

[0042] According to one aspect, the electrical generation system includes a plurality of electrical switches, and the control device is configured to control the plurality of electrical switches in order to achieve electrical isolation of one or more pieces of equipment in the electrical generation system.

[0043] In one aspect, each converter is configured to detect an internal fault by measuring current and voltage within the converter. Preferably, each converter performs a functional test during which the distribution voltage and distribution current are compared to predetermined thresholds.

[0044] According to one aspect, each converter is configured to switch to a safety mode following the detection of a fault external to the converter.

[0045] According to one aspect, each converter being in a given regulation mode, auxiliary or voltage, each converter is configured to switch to a safety mode following the detection of a fault on said aircraft network, and to return to said given regulation mode following the electrical isolation of said fault.

[0046] In one aspect, the electrical generation system includes an electrical distribution unit configured to be electrically connected to the aircraft's electrical network. The electrical distribution unit is powered by at least two converters. The electrical distribution unit is configured to detect a distribution fault by measuring current and / or voltage within the unit.

[0047] In one aspect, each converter is configured to detect a distribution fault by current and / or voltage measurements in the electrical distribution unit.

[0048] According to one aspect, each converter is configured to: perform a control test including a step of comparing a value of the distribution voltage to a predetermined minimum threshold and switch directly from auxiliary regulation to voltage regulation after a successful control test, in particular, if the value of the distribution voltage is greater than the minimum threshold.

[0049] The invention also relates to an aircraft comprising an aircraft network and at least one aircraft turbomachine comprising a low-pressure shaft and a high-pressure shaft configured to be driven in rotation, at least one electrical generation system as previously described, supplying the aircraft network.

[0050] The invention also relates to a method of electrical generation for supplying at least one electrical network of an aircraft from an electrical generation system as described above, the aircraft comprising at least one aircraft turbomachine including a low-pressure shaft and a high-pressure shaft configured to be driven in rotation, a first converter being in voltage regulation, a second converter being in auxiliary regulation, the first converter and the second converter being in nominal mode, the method comprising steps during which: the first converter detects an internal fault, the first converter switches from nominal mode to a fault mode following the detection of the internal fault, the first converter communicates its fault mode to at least the second converter,and the second converter switches directly from auxiliary regulation to voltage regulation upon receiving the fault mode signal from the first converter.

[0051] Preferably, the second converter switches directly from auxiliary regulation to voltage regulation upon receiving the fault mode of the first converter after the first converter is electrically isolated.

[0052] It goes without saying that the role of the converters could be reversed. The first converter could be in voltage regulation and the second converter could be in auxiliary regulation.

[0053] The invention also relates to a computer program-type product, comprising at least one sequence of instructions stored and readable by a processor, which, once read by that processor, causes the execution of the steps of the process as described above. Preferably, the processor belongs to a converter. PRESENTATION OF THE FIGURES

[0054] The invention will be better understood upon reading the following description, given by way of example, and referring to the following figures, given by way of non-limiting examples, in which identical references are given to similar objects.

[0055] This is a schematic representation of an electrical generation system drawing mechanical energy from an aircraft turbomachine.

[0056] This is a schematic representation of the electrical generation system with its generators, converters, an electrical distribution unit and a control device.

[0057] This is a schematic representation of an electrical generation system that draws mechanical energy from an aircraft turbomachine according to one embodiment of the invention.

[0058] Laest is a schematic representation of the electrical generation system with its converters, an electrical distribution unit and a control device according to one embodiment of the invention.

[0059] This is a schematic representation of the electrical generation system in the absence of faults.

[0060] This is a schematic representation of the electrical generation system following the occurrence of an internal fault in a converter.

[0061] This is a schematic representation of the electrical generation system following electrical insulation.

[0062] This is a schematic representation of the electrical generation system after reconfiguration.

[0063] This is a schematic representation of the electrical generation system following the occurrence of a fault in the electrical distribution unit.

[0064] This is a schematic representation of the electrical generation system following the occurrence of an internal fault in a power cable.

[0065] It should be noted that the figures explain the invention in detail for implementing the invention, said figures being of course able to serve to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0066] With reference to the diagram, an electrical generation system 1 for an aircraft is shown. The aircraft includes a turbomachine T comprising a low-pressure shaft BP and a high-pressure shaft HP. In this example, the turbomachine T has a low-pressure compressor 71 and a low-pressure turbine 74 connected by the low-pressure shaft BP, and a high-pressure compressor 72 and a high-pressure turbine 73 connected by the high-pressure shaft HP.

[0067] The electrical generation system 1 is configured to draw mechanical energy from the low-pressure shaft BP and mechanical energy from the high-pressure shaft HP to supply an aircraft electrical network REA, hereinafter referred to as the aircraft network REA, with a calibrated voltage. The electrical generation system 1 can also be connected to electrical sources BAT or to electrical equipment to be powered LOAD, for example, electric propulsion motors.

[0068] In practice, as will be shown later, the electrical generation system 1 more generally allows for electrical hybridization to enable power to be drawn from or injected into the turbomachine T.

[0069] With reference to the diagram, the electrical generation system 1 comprises two generators, G1 and G2, connected respectively to the low-pressure shaft BP and the high-pressure shaft HP of the turbomachine T. The electrical generation system 1 includes: A first power supply path V1 comprising: A first generator G1 configured to generate alternating current by drawing mechanical energy from the low-pressure shaft BP; A first converter C1, associated with the first generator G1, to convert the generated alternating current into a first distribution current I DC1 Depending on its configuration, a second power supply channel V2 comprises: a second generator G2 configured to generate alternating current by drawing mechanical energy from the high-pressure shaft HP; and a second converter C2, associated with the second generator G2, to convert the generated alternating current into a second distribution current I. DC2. Depending on its settings,

[0070] In this example, generators G1 and G2 are preferably electrical machines capable of operating in either generator or motor mode. As is known, each electrical machine comprises a rotor attached to a rotating shaft (here, a low-pressure (LP) or high-pressure (HP) shaft) and a stator with windings designed to generate three-phase alternating currents. The structure and operation of such an electrical machine are well-established and will not be described in further detail.

[0071] With reference to the, the electrical generation system 1 includes an electrical distribution unit EDU which is electrically connected to the aircraft network REA, to the electrical sources BAT or to the electrical loads LOAD.

[0072] Each converter C1, C2 provides a distribution voltage V DCto the electrical distribution unit EDU. Preferably, the electrical distribution unit EDU includes a voltage bus.

[0073] Each converter C1, C2 is connected to the electrical distribution unit EDU by one or more power cables H1, H2, also called power harnesses, configured to transmit electrical power.

[0074] As is known, each converter C1, C2 comprises a plurality of switching arms with switches, specifically transistors, which allow modification of the generated electrical power and the mechanical power drawn from each shaft BP, HP to adapt the distribution current I DC1 , I DC2 depending on the needs.

[0075] According to the invention, with reference to the, the electrical generation system 1 includes a control device 2 connected to each converter C1, C2 so as to know the state of each converter but also data from each converter C1, C2 (incoming / outgoing current, input / output voltage, etc.).

[0076] The control device 2 is also connected to the electrical distribution unit EDU in order to know its state but also its data (incoming / outgoing current, input / output voltage, etc.).

[0077] With reference to the diagram, the control device 2 is connected to a set of switches 7 in order to electrically isolate each converter C1, C2, and also the electrical distribution unit EDU. The control device 2 knows the state of each switch 7 so as to quickly determine whether a converter C1, C2 is isolated or whether the electrical distribution unit EDU is isolated.

[0078] The electrical distribution unit EDU and the control device 2 together form a distribution and protection unit PDMU.

[0079] With reference to the, the electrical generation system 1 is configured to receive an operating instruction P ECU This operating instruction P is derived from the ECU monitoring computer of the turbomachine T. ECU includes a first parameter setting P CONS1 for the first converter C1 and a second parameter setting P CONS2 for the second converter C2.

[0080] Preferably, each parameter setting P CONS1 , P CONS2 allows the switching of the transistors in converters C1 and C2 to be controlled. Preferably, each converter C1 and C2 includes a control block configured to convert a parameter setpoint P CONS1 , P CONS2in the form of a pulse-width modulation (PWM) signal. Such a control block is familiar to those skilled in the art. Each parameter setting P CONS1 , P CONS2 is either a voltage regulation setpoint RegU to control the converter C1, C2 to a distribution voltage setpoint V DC * be a setpoint in auxiliary regulation RegA, for example, a power regulation setpoint or a torque regulation setpoint configured to control the converter C1, C2 to a power / torque of the high pressure shaft HP or the low pressure shaft BP of the aircraft turbomachine T.

[0081] Preferably, among all the converters C1, C2, at least one of the converters C1, C2 is in voltage regulation mode to ensure a distribution voltage V DC* to the EDU electrical distribution unit.

[0082] As is known, the electrical generation system 1 can be interrupted in the event of a fault for a maximum interruption duration of approximately 200 ms. For example, in the case of electric propulsion, this corresponds to the maximum duration during which the electric propulsion motors do not provide thrust.

[0083] In this example, with reference to the diagram, converters C1 and C2 are directly connected by a communication cable Q3, enabling direct and rapid communication without going through the ECU (Engine Control Unit). Preferably, this communication cable Q3 uses discrete signals (e.g., DSi, DSo) to ensure responsive communication.

[0084] In this example, converters C1 and C2 are each directly connected to the control unit 2 by at least one communication cable Q1 and Q2, enabling direct and rapid communication without going through the ECU. Preferably, each communication cable Q1 and Q2 carries discrete signals (e.g., DSi, DSo) to ensure responsive communication. Preferably, converters C1 and C2 are not directly connected to each other by a communication cable Q3, but indirectly through the control unit 2.

[0085] In this document, each C1, C2 converter can be configured in at least two operating modes: a nominal mode M1 corresponding to normal, fault-free operation, and a fault mode M3 corresponding to a shutdown of operation upon detection of an internal fault by the C1, C2 converter itself. During such an internal fault, the C1, C2 converter no longer switches and must be electrically isolated. The M3 fault mode corresponds to the detection of an internal fault, such as a short circuit, in the C1, C2 converter, which cannot be repaired in flight and requires human intervention on the ground.

[0086] Depending on one aspect, each converter C1, C2 can be configured according to a safety mode M2, corresponding to limited operation with degraded performance. Safety mode M2 ​​is activated autonomously by a converter upon detection by the converter itself and / or the control device 2 of a minor fault, specifically, an external fault affecting said converter C1, C2. The external fault could be a fault in a power cable between a converter and the EDU distribution unit, a fault within the EDU distribution unit, or a fault on the aircraft electrical network (REA). The switching operations of converter C1, C2 are temporarily halted while the external fault is investigated. Fault mode M3 takes precedence over safety mode M2 ​​to maintain a high level of safety.

[0087] With reference to the diagram, the electrical generation system 1 comprises a plurality of electrical switches 7, specifically between each converter C1, C2 and the electrical distribution unit EDU, and between the electrical distribution unit EDU and the aircraft electrical network REA. As will be described in detail later, the control device 2 is configured to operate the plurality of electrical switches 7 in order to achieve electrical isolation of one or more pieces of equipment in the electrical generation system 1 based on the detection and location of electrical faults.

[0088] With reference to figures 6 to 8, the invention is remarkable in that each converter C1, C2 is configured to: detect (step E1) an internal fault DEFi, i.e. of the converter C1, C2 concerned, switch (step E2) from a nominal mode M1 to a fault mode M3 in case of detection of an internal fault DEFi, communicate (step E3) its operating mode M1 or M3 to at least one other converter C1, C2, and switch E4 directly from an auxiliary regulation RegA to a voltage regulation RegU upon receipt of a fault mode M3 of at least one other converter C1, C2.

[0089] Internal DEFi default refers to a major converter defect that cannot be repaired in flight.

[0090] Thus, in the event of a fault in one of the converters, the other converter(s) C1, C2 can automatically and rapidly reconfigure themselves without intervention from the ECU. This improves responsiveness for reconfiguration within the maximum interruption time limit. Furthermore, the propagation of a fault between converters C1 and C2, as in prior art, is advantageously avoided. Advantageously, converters C1 and C2 have identical functions, allowing for similar reconfiguration in the event of a fault in one of them. The electrical generation system 1 is therefore scalable to multiple supply channels V1, V2.

[0091] Internal fault of a converter

[0092] According to step E1, each converter C1, C2 is configured to detect an internal DEFi fault, specifically an internal short-circuit fault. In one aspect, each converter C1, C2 is configured to detect an internal DEFi fault by measuring its distribution currents and voltages.

[0093] For this purpose, each converter C1, C2 is configured to perform a functional test. In this example, the functional test mainly comprises two comparison steps: a comparison of the distribution voltage Vdc to a predetermined voltage threshold Vs1, for example, 450V. This is to determine if the distribution voltage Vdc supplied by the power converter in question is lower than the threshold Vs1 (Vdc < Vs1), which is an indicator of a short-circuit fault (the voltage Vdc collapses); and a comparison of the distribution current Idc to a predetermined current threshold Is1, for example, 200A. This is to determine if the distribution current Idc supplied by the converter is too high (Idc > Is1), which, combined with a collapsed voltage Vdc, indicates or confirms the presence of a short circuit.

[0094] Such an internal DEFi fault is a major fault, as it cannot be repaired in flight. The converter that detects such an internal DEFi fault is configured to switch from a nominal mode M1 to a fault mode M3 (stage E2).

[0095] According to step E3, each converter C1, C2 is configured to communicate its operating mode M1 or M3 to at least one other converter C1, C2. Alternatively, each converter C1, C2 is configured to directly communicate its operating mode M1 or M3 to the control device 2, specifically its fault mode M3. The control device 2 centralizes the states of the various elements of the power generation system 1. Each converter C1, C2 thus reactively communicates its operating mode M1-M3 to the other equipment in the power generation system 1.

[0096] According to a preferred aspect, in a similar way, each C1, C2 converter is configured to directly communicate its M1-M3 operating mode to the ECU supervisory computer so that the latter performs global but slow supervision.

[0097] In this case, if the first converter C1 experiences an internal DEFi fault, the control device 2 electrically isolates the first converter C1 by controlling switches 7 (switch 7 open). Preferably, electrical isolation confirmation is transmitted to each converter C1, C2 by the control device 2 to ensure electrical safety.

[0098] According to step E4, the second converter C2 is configured to switch directly from auxiliary regulation RegA to voltage regulation RegU upon receiving a fault mode M3 from the first converter C1. Preferably, such a switchover is performed only when the first faulty converter C1 has been electrically isolated.

[0099] When several converters C1, C2 supply power to an aircraft electrical network REA, at least one converter C1, C2 operates in RegU voltage regulation mode to ensure power quality. If power quality is satisfactory, one or more converters may switch to RegA auxiliary regulation mode following an instruction from the ECU (Engine Control Unit). Thanks to the invention, in the event of a failure of a converter that was in RegU voltage regulation mode, at least one functioning converter will reactively and autonomously switch from RegA auxiliary regulation mode to RegU voltage regulation mode after electrical isolation of the faulty converter by the control device 2.

[0100] Control device 2 manages electrical isolation (control of isolation switches 7) solely based on discrete signal exchanges, allowing network quality to be restored in an optimal timeframe. This switchover is performed autonomously by the second healthy converter C2, and reactively, meaning rapidly, in response to the discrete signal exchanges.

[0101] Preferably, before the E4 switching step, the second converter C2 performs a control test. This control test includes a step comparing the value of the distribution voltage Vdc to a predetermined minimum threshold. For example, the control test includes a step verifying that the distribution voltage Vdc is not too low to resume voltage regulation RegU. In this example, it is verified that the amplitude of the distribution voltage Vdc is greater than a predetermined minimum threshold, for example, 200V.

[0102] The Q1, Q2, and Q3 communication cables, particularly those with discrete signals, enable rapid communication, specifically with a maximum confirmation time of 5 ms. This ensures simple, fast, and robust reactivation of the Vdc distribution voltage control. Preferably, the discrete signals are redundant.

[0103] Texterne default

[0104] According to another aspect, with reference to the control device 2, it is configured to detect an external fault, such as a fault in a power cable between a converter and the EDU distribution unit, a fault in the distribution of the EDU distribution unit or a fault on the aircraft electrical network REA, based on the data (incoming / outgoing current, input / output voltage, etc.) of the converters and the electrical distribution unit.

[0105] DEFh cable fault

[0106] In particular, the control device 2 is configured to detect a DEFh cable fault of a power cable H1, H2, electrically isolate the power cable H1, H2 having the DEFh cable fault, in particular, by controlling the switches 7.

[0107] Alternatively or cumulatively, the converter C1, C2 connected to the power cable H1, H2 can also detect a cable fault DEFh to inform the control device 2 and thus electrically isolate the power cable H1, H2. For this purpose, the converter C1, C2 receives information from the control device 2. In one example, the power cable H1 of the first channel V1 is the one with the fault, but it goes without saying that it could be the one of the second channel V2. The monitoring is identical for both channels V1 and V2.

[0108] As an example, control device 2 and / or each converter C1, C2 is configured to perform a functional test of a power cable H1, H2. In one aspect, the functional test is configured to analyze the incoming and outgoing current of a power cable H1, H2. Specifically, if the incoming and outgoing currents do not flow in the same direction (same sign), a cable fault DEFh is detected, specifically a short circuit. Alternatively, a cable fault DEFh can be detected if the difference between the incoming current in the power cable H1, H2 and the outgoing current from the power cable H1, H2 exceeds a predetermined threshold.

[0109] When a DEFh cable fault is detected, the affected power cable H1, H2 is electrically isolated, in particular by controlling the switches 7 by the control device 2. According to one aspect, the converter C1, C2, associated with the faulty power cable H1, H2 is also isolated.

[0110] Following a cable fault DEFh, each converter C1, C2 is in a safety mode M2. Preferably, the converter C1, C2 not associated with the power cable H1, H2 experiencing the cable fault DEFh is configured to switch directly from auxiliary regulation RegA to voltage regulation RegU after the electrical fault is isolated. This ensures optimal power supply.

[0111] Preferably, the converter C1, C2, which is not associated with the power cable H1, H2 having the cable fault DEFh, is configured to switch to nominal mode M1 following the clarification of the fault.

[0112] Thus, electrical safety is ensured even in the event of a fault in an H1, H2 power cable.

[0113] Automatic reactivation of converter C1, C2, which is not associated with the power cable H1, H2 (due to cable fault DEFh), can be achieved by verifying that the distribution voltage Vdc exceeds a voltage threshold. In this example, it is verified that the amplitude of the distribution voltage Vdc exceeds a predetermined minimum threshold, for example, 200V. Furthermore, a difference is calculated between the value of the distribution voltage Vdc and the value of the distribution voltage Vdc filtered at 15 Hz, and then the evolution of this difference is monitored to ensure that it increases, thus resuming voltage regulation RegU.

[0114] Aircraft electrical fault REA

[0115] In the event of a fault on the aircraft electrical network (REA), control device 2 and converters C1 and C2 are not configured to detect and resolve the fault. The fault on the aircraft electrical network is an external fault, and each converter C1 and C2 switches to safety mode M2. Following resolution of the external fault by an external device (not shown), the automatic reactivation of converters C1 and C2 is performed in a manner analogous to a cable fault (DEFh) as described previously. Converters C1 and C2 remain in the control mode they were in before the fault occurred on the aircraft electrical network.

[0116] Default PDMU

[0117] According to one aspect, with reference to the, the electrical distribution unit EDU is configured to detect a distribution fault DEFd of the electrical distribution unit EDU by current and / or voltage measurements in the electrical distribution unit EDU.

[0118] As an example, control device 2 and / or the electrical distribution unit (EDU) is configured to perform a functional test of the EDU. In one aspect, the functional test is configured to compare the sum of the incoming currents to the sum of the outgoing currents of the EDU. Specifically, if the difference between the sum of the incoming currents (Ie) and the sum of the outgoing currents (Is) exceeds a predetermined threshold, a distribution fault (DEFd) is detected.

[0119] When a DEFd distribution fault is detected, the EDU electrical distribution unit is electrically isolated and no further electrical generation is possible.

[0120] General example

[0121] An electrical generation process will be presented according to an implementation example.

[0122] This generation process enables fault detection, fault localization for electrical isolation, and subsequent restoration of network quality. Specifically, it ensures that at least one electrical converter (C1, C2) provides voltage regulation (RegU) for the electrical distribution unit (EDU). This control takeover is performed autonomously and in a decentralized manner by converters C1 and C2.

[0123] According to the invention, the generation process is configured to perform monitoring of internal faults of converters C1, C2 but also of external faults such as faults of power cables H1, H2, of the electrical distribution unit EDU or of the aircraft electrical network REA.

[0124] In this implementation example, with reference to the diagram, the first converter C1 is in voltage regulation mode (RegU) while the second converter C2 is in auxiliary regulation mode (RegA). Thus, it is the first converter C1 that ensures power quality by regulating the distribution voltage (Vdc). Both the first converter C1 and the second converter C2 are in nominal mode (M1).

[0125] During the aircraft's flight, an internal short circuit occurs in the first converter, C1, as illustrated in Figure 1. The first converter, C1, detects an internal fault, DEFi, by measuring currents and voltages during its functional test. Following the detection of the internal fault, DEFi, as shown in Figure 1, the first converter, C1, switches from nominal mode M1 to fault mode M3 and directly communicates its fault mode M3 via a corresponding discrete signal transmitted to the second converter, C2, via communication cable Q3, and to control device 2 via communication cable Q1.

[0126] With reference to the, upon receipt of this discrete signal indicating the fault mode M3 of converter C1, the control device 2 electrically isolates this converter C1 having the internal fault DEFi by controlling the various switches 7.

[0127] With reference to the second converter, C2, which in this example is in nominal mode M1 and auxiliary regulation RegA, performs a control test to verify if voltage regulation is possible, specifically by checking that the distribution voltage Vdc is not too low (by comparison to a threshold). The control test performed by the second converter C2 includes the step of first ensuring that it has been informed by control device 2 that the first converter C1 is properly electrically isolated.

[0128] If the conditions are met, the second converter C2 switches from auxiliary regulation RegA to voltage regulation RegU upon receiving the discrete signal indicating a fault mode M3 from the first converter C1. This switchover is direct, or autonomous, in that it is independent of the ECU monitoring computer, which ensures high responsiveness.

[0129] The second converter C2 then provides voltage regulation RegU, which ensures the quality of the electrical network by regulating the distribution voltage Vdc.

[0130] Advantageously, after clarification of the fault, the ECU monitoring computer will then transmit a new parameter instruction Pcons2 to the second converter C2 in order to regain control.

[0131] Regarding external faults, in the event of a distribution fault DEFd in the electrical distribution unit EDU, the latter is isolated by control device 2 through the activation of switches 7. Similarly, in the event of a cable fault DEFh in the power cable H1 between the first converter C1 and the electrical distribution unit EDU, the cable fault DEFh is isolated by control device 2 through the activation of switches 7 (fault clarified). The first converter C1 and the second converter C2 enter safety mode M2 ​​due to an external fault. If the second converter C2, which is not connected to the power cable H1 with the cable fault DEFh, is in auxiliary regulation RegA, the second converter C2 switches directly from auxiliary regulation RegA to voltage regulation RegU following the electrical isolation of the fault.This allows for a reactive approach to ensuring the quality of the electrical network by regulating the distribution voltage Vdc.

[0132] Once the DEFh cable fault has been clarified and it has been verified that the distribution voltage Vdc is above a predetermined threshold and that its increase is consistent with the previously described model, the second converter C2 returns to nominal mode M1 while the first converter C1 remains in safety mode M2. The ECU supervisory control unit will transmit new parameter instructions Pcons1 and Pcons2 to restore control.

[0133] In the event of an aircraft electrical network (REA) fault, typically a short-circuit fault, converters C1 and C2 are configured to switch to M2 safety mode because the fault is not internal to converters C1 and C2. For example, converters C1 and C2 can switch to M2 safety mode upon detection by converters C1, C2, or the EDU of an undervoltage or overcurrent.

[0134] As soon as the ECU (Engine Control Unit) has identified (located and isolated) the faulty (short-circuited) section of the network, converters C1 and C2 will autonomously reactivate their control. As previously described, a control test, as demonstrated earlier for a DEFh cable fault, is performed before resuming full control. Converters C1 and C2 remain in the regulation mode they were in before the fault occurred on the aircraft electrical network (REA).

[0135] Thus, the electrical generation system 1 is robust and can react quickly to any fault, which prevents the propagation of faults in all the equipment of the electrical generation system 1 which could lead to a shutdown of electrical generation.

Claims

Electrical generation system (1) for supplying at least one aircraft electrical network, hereinafter referred to as the aircraft network (ASN), the aircraft comprising at least one aircraft turbomachine (T) comprising a low-pressure shaft (LP) and a high-pressure shaft (HP) configured to be driven in rotation, the electrical generation system (1) comprising at least: A first power supply path (V1) comprising: A first generator (G1) configured to generate alternating current by drawing mechanical energy from one of the low-pressure (LP) and high-pressure (HP) shafts, A first converter (C1), associated with the first generator (G1) to supply the aircraft network (ASN) via at least one first power cable (H1), A second power supply path (V2) comprising: A second generator (G2) configured to generate alternating current by drawing mechanical energy from the other of the low-pressure (LP) and high-pressure (HP) shafts,A second converter (C2), associated with the second generator (G2) to supply the aircraft network (REA) via at least one second power cable (H1), the electrical generation system (1) being configured to receive a first parameter setting instruction (P, CONS1 ) for the first converter (C1) and a second parameter setting (P CONS2 ) for the second converter (C2), each parameter setting (P CONS1 , P CONS2 ) being either a voltage regulation setpoint (RegU) to control the converter (C1, C2) to a distribution voltage setpoint (V DC* ) either an auxiliary control setpoint (RegA), at least one of the parameter setpoints (P CONS1 , P CONS2) being a setpoint in voltage regulation (RegU), Electrical generation system (1) characterized by the fact that, each converter (C1, C2) is configured to: detect an internal fault (DEFi), switch from a nominal mode (M1) to a fault mode (M3) in case of detection of an internal fault (DEFi), communicate its operating mode (M1,M3) to the other converter (C1, C2), and switch directly from an auxiliary regulation (RegA) to a voltage regulation (RegU) upon receipt of a fault mode (M3) from at least one other converter (C1, C2). Electrical generation system (1) according to claim 1, comprising a control device (2) connected to each converter (C1, C2) by at least one communication cable (Q1, Q2) so as to know the state of each converter (C1, C2) but also data of each converter (C1, C2), the control device (2) is connected to a set of switches (7) so as to electrically isolate each converter (C1, C2). Electrical generation system (1) according to claim 2, wherein the communication cable (Q1, Q2) is a discrete signal communication cable. Electrical generation system (1) according to any one of claims 2 to 3, wherein each converter (C1, C2) is configured to directly communicate its operating mode (M1-M3) to the control device (2), the control device (2) being configured to electrically isolate the converter (C1, C2) having the internal fault (DEFi). Electrical generation system (1) according to any one of claims 1 to 4, wherein the control device (2) is configured to: detect a cable fault (DEFh) of a power cable (H1, H2), and electrically isolate the power cable (H1, H2) having the cable fault (DEFh). Electrical generation system (1) according to claim 5, wherein each converter (C1, C2) being in a safety mode (M2) following the detection of the cable fault (DEFh), the converter (C1, C2), which is not associated with the power cable (H1, H2) having the cable fault (DEFh), is configured to switch directly from an auxiliary regulation (RegA) to a voltage regulation (RegU) following the electrical isolation of the fault. Electrical generation system (1) according to any one of claims 1 to 6, comprising an electrical distribution unit (EDU) configured to be electrically connected to the aircraft electrical network (REA), the electrical distribution unit (EDU) being powered by at least two converters (C1, C2), the electrical distribution unit (EDU) being configured to detect a distribution fault (DEFd) by current and / or voltage measurements in the electrical distribution unit (EDU). Aircraft comprising an aircraft network (ASN) and at least one aircraft turbomachine (T) comprising a low pressure shaft (LP) and a high pressure shaft (HP) configured to be driven in rotation, at least one electrical generation system (1), according to any one of claims 1 to 7, supplying the aircraft network (ASN). A method for generating electricity to supply at least one aircraft electrical network (AAN) from an electrical generation system (1) according to any one of claims 1 to 7, the aircraft comprising at least one aircraft turbomachine (T) comprising a low-pressure shaft (LP) and a high-pressure shaft (HP) configured to be driven in rotation, a first converter (C1) being in voltage regulation (RegU), a second converter (C2) being in auxiliary regulation (RegA), the first converter (C1) and the second converter (C2) being in nominal mode (M1), the method comprising steps in which: the first converter (C1) detects an internal fault (DEFi), the first converter (C1) switches from nominal mode (M1) to a fault mode (M3) following the detection of the internal fault (DEFi), the first converter (C1) communicates its fault mode (M3) to at least the second converter (C2),The second converter (C2) switches directly from auxiliary regulation (RegA) to voltage regulation (RegU) upon receiving the fault mode (M3) from the first converter (C1).

Images