Intelligent electric motor with electrical redundancy and integrated fault detection

Abstract

The invention relates to an intelligent motor (10) comprising: - an electromechanical permanent magnet converter (12); and - an electronic control unit; the electromechanical converter (12) comprises: - a permanent magnet rotor (121); and - a stator (122) comprising: - a first assembly comprising at least three phases electrically coupled to each other in a star configuration; - a second assembly comprising the same number of phases as the first assembly, the phases of the second assembly being electrically coupled to each other in a star configuration; and - an impedance between the neutral points of the stars of the first and second assemblies; the electronic control unit (18) comprises a control inverter comprising the same number of independent control arms as phases in the first assembly and the same number of independent control arms as phases in the second assembly;The control inverter is configured to control each phase of the first set and each phase of the second set through their own control arms; The electronic control unit is configured to measure a voltage difference between the star neutral points of the first and second sets with respect to a voltage reference common to the sets.

Description

SMART ELECTRIC MOTOR WITH ELECTRICAL REDUNDANCY AND INTEGRATED FAULT DETECTION

[0001] This presentation relates to an intelligent electric motor, in particular for an aircraft, and more particularly to the electrical architecture of an intelligent electric motor with several electrical channels, with integrated fault detection in order to reinforce its operational safety. State of the art

[0002] The electric motor has recently become interesting in vehicular applications, and in particular aerospace, to promote the low carbon footprint associated with its use, its flexibility of implementation, its efficiency (only the necessary energy is consumed), its reliability (limited maintenance) and also the potential reduction in mass and volume that it generates compared to a conventional propulsion system (thermal with hydraulic or pneumatic energy distribution).

[0003] It is then easy to understand that the constraints of mechatronic integration (mass and volume) of the electric motor assembly, controller (power electronics and control electronics), filtering and cooling system and operational safety are a key issue of this change, in particular to obtain a propulsion assembly whose mass and size remain low.

[0004] An architecture of a smart motor with a gearbox and a plurality of independent windings is known. Each winding is powered by an H-bridge converter, but the input filtering is not integrated into the smart motor. Therefore, the architecture is relatively bulky. Furthermore, the presence of a gearbox in the smart motor affects the reliability of the motor and / or leads to an increase in scheduled maintenance operations, compared to a smart motor without an integrated gearbox.

[0005] A smart motor is also known that has two groups of three coils electrically coupled in a star configuration, with the neutrals of the two groups electrically connected to each other to have an electrical common point and balance the currents. This configuration is relatively inexpensive to implement. However, this configuration allows a failure in one of the groups to disrupt the operation of the other group.

[0006] Patent FR 3089715 discloses a motor whose stator comprises two three-phase assemblies which are electrically decoupled from each other. The purpose of the following presentation is to demonstrate that, on the contrary, a well-designed electrical coupling can provide an improvement in the ability to detect failures or behavioral anomalies of the stator assemblies. Purpose of the presentation

[0007] This presentation aims to provide an intelligent motor architectural solution to ensure the supply of mechanical torque even in the event of a (total or partial) failure of a voltage inverter arm of a stator star or in the event of a failure of an entire stator star, and also to detect a failure in one of the stars of its stator.

[0008] A (each) given control arm of the inverter drives only one phase of a single set.

[0009] In a first subject of the disclosure, an intelligent motor is proposed comprising a permanent magnet electromechanical converter and an electronic control unit. The electromechanical converter comprises a permanent magnet rotor and a stator. The stator comprises a first set, comprising at least three phases electrically coupled to each other in a star configuration, a second set, comprising as many phases as the first set, the phases of the second set being electrically coupled to each other in a star configuration, and an impedance between the neutral points of the stars of the first and second sets. The electronic control unit comprises a control inverter, comprising as many independent control arms as there are phases of the first set and as many independent control arms as there are phases of the second set.The control inverter is configured to drive each phase of the first set and each phase of the second set by its own control arms. The electronic control unit is configured to measure a voltage difference between neutral points of the stars of the first and second sets with respect to a voltage reference common to said sets.

[0010] The electrical coupling of the neutral points of the stars of the first and second sets, and the voltage measurement between them, allows the motor to detect a failure (total or partial short circuit, interruption of a motor phase, conductor degradation, open circuit, loss of open circuit transistor, open failure, etc.) of the stator. If the failure is detected early enough, it is even possible to change the operation of the motor so as to avoid overheating of the motor and / or damage to its components (for example, the stator conductors).

[0011] Impedance can help not only to generate a voltage difference when a current exists between the neutral points of the assemblies, but also to limit this current. The electronic control unit can be configured to measure the voltage across the impedance.

[0012] In the intelligent motor according to the disclosure, the two star sets can be wound successively and not simultaneously, which takes more time than simultaneous winding but can allow for magnetic and / or electrical decoupling, and / or can allow for mechanical segregation of the coils of the two sets. Balancing of the torques produced by the controlled currents is achieved by the way in which each set of coils is wound separately. The winding must therefore be more complex than in the configuration where the two sets of coils are wound simultaneously (because two independent windings are produced, instead of a single winding comprising two wires electrically insulated from each other).

[0013] In the smart motor according to the disclosure, the coils of the different assemblies can be distributed around the rotation axis of the rotor of the smart motor so as to be geometrically separated from each other. Geometric separation, in other words mechanical segregation, can limit or even prevent the propagation of a fault in one of the assemblies to another via conduction and / or electrical induction and / or thermal transfer.

[0014] The motor may be configured to isolate the first and second sets from each other in response to the voltage between the neutral points of their stars exceeding a voltage threshold.

[0015] Thus, the faulty assembly would no longer be driven when the motor continues to drive the non-faulty assembly.

[0016] The motor may be configured to measure the voltage at each terminal of each phase of the first and second sets, and signal a fault in the given sets in response to a difference between the voltages of two of its phases exceeding a divergence threshold. In addition or alternatively, the motor may be configured to measure the voltage at each terminal of each phase of the first and second sets, and the current of each coil supply, to locate a fault in one of the given sets in response to a voltage threshold exceeding by the voltage between the neutral points of the stars of the first and second sets.

[0017] This allows the motor to identify which assembly would fail, even when the stator only has two assemblies. However, the motor can be configured this way regardless of the number of assemblies in the stator.

[0018] The stator may comprise at least one assembly other than the first and second assemblies, each comprising as many phases as the first assembly, electrically coupled to each other in a star configuration. The inverter may further comprise as many independent control arms as there are phases of the (set of) assembly(s) other than the first and second assemblies. The inverter may be further configured to drive each phase of the (set of) assembly(s) other than the first and second assemblies by its own control arm.The electronic control unit may be further configured to measure a voltage difference between the star neutral point of the first set and the star neutral point of the (one) set(s) other than the first and second sets, and to measure a voltage difference between the star neutral point of the second set and the star neutral point of the (one) set(s) other than the first and second sets.

[0019] When the smart motor has more than two sets, it can at least measure the voltage difference between a neutral point of one of the sets and those of two other sets, or even measure the voltage difference between the neutral points of all the sets taken two by two.

[0020] The smart motor can be free of a gearbox inside its housing, the housing, or casing, housing the electromechanical converter and the control unit. This can allow for a gain in volume and mass as well as an increase in reliability and maintenance.

[0021] The electromechanical converter can be a synchronous machine.

[0022] The stator of the electromechanical converter may comprise a series of teeth arranged in a circumferential direction of the stator. For example, the series of teeth may be implemented as a ring gear and / or a stack of laminations having radial projections separated from each other in the circumferential direction by radial notches. Each phase may comprise a coil wound around a single tooth of the stator, or a series of several coils wound around a single tooth of the stator. A "stator tooth" is understood to mean a tooth of a ring gear or a radial projection of a stack of laminations.

[0023] Thus, each of the coils in each of the sets can be wound around a single tooth of the ring gear, which can help to minimize the size of the stator, especially the size of the coil head.

[0024] The rotor may include magnets arranged in a Halbach configuration (Halbach array in English), which can increase the specific torque of the smart motor.

[0025] The stator of the electromechanical converter can be divided into separate angular ranges, the number of angular ranges of a stator corresponding to the number of three-phase sets of the stator, the angular range extending over an angle corresponding to the result of dividing 360° by the number of sets of the stator, or by an integer multiple of the number of sets of the stator.

[0026] In the case of a two-set stator, the coils of the first set would thus be arranged over a first angular range of the stator extending over 180° mechanically and the coils of the second set could be arranged over a second angular range of the stator extending over 180° mechanically, the first angular range being distinct from the second range.

[0027] The first set of coils and the second set of coils are therefore located on two distinct parts of the perimeter of a circle. This can facilitate mechanical, magnetic, electrical and / or thermal segregation between the two sets of coils, in particular so that a defect possibly present on a coil of one of the sets does not propagate to, and / or damage a part of another of the sets.

[0028] The control unit may further comprise a module for regulating the current in each set of coils independently of the other set of coils, and / or a module for regulating the speed of the rotor.

[0029] The control unit can be configured to operate with and / or without a mechanical rotor position sensor. The mechanical position sensor can provide the angular mechanical position of the rotor (relative to the stator) to which the sensor is connected. This can allow the control unit to have this position information to be able to regulate the currents in the two sets of stator windings. In the case where the motor is equipped with a rotor position sensor, this sensor can have a measuring channel that is used by all sets – or one sensor per set.

[0030] When the position sensor is not mounted or when the position information from the sensor is lost, a position estimation process can be implemented by the control unit's regulation module to ensure the current regulation function in the two stator windings.

[0031] The electronic control unit may advantageously further comprise a connection interface connecting a high voltage DC power supply bus to each of the arms of the inverter and comprising a capacitive decoupling stage provided with differential mode capacitors. List of drawings

[0032] Other characteristics and advantages of the technology which is the subject of the disclosure will appear on reading the following description of several embodiments of the technology which is the subject of the disclosure, given by way of example and with reference to the attached drawings.

[0033] The present schematically shows an aircraft with several propulsion rotors equipped with an electric propulsion system according to one embodiment.

[0034] The diagram schematically represents a fixed-wing aircraft and several propulsion rotors equipped with an electric propulsion system according to one embodiment.

[0035] The diagram schematically represents a sectional view of an intelligent motor of the propulsion system according to a first embodiment of the intelligent motor.

[0036] It is a schematic representation of a circumferential arrangement of two sets of at least three phases.

[0037] It is a schematic representation of a circumferential arrangement of two sets of at least three phases.

[0038] It is a schematic representation of a circumferential arrangement of two sets of at least three phases.

[0039] This is a schematic representation of the electrical architecture, according to a first embodiment, of the electromechanical converter of the intelligent motor of the.

[0040] Schematically presents an electrical architecture, according to a second embodiment, of the electromechanical converter of the intelligent motor of the.

[0041] Schematically presents an electrical architecture, according to a third embodiment, of the electromechanical converter of the intelligent motor of the. Detailed description of the invention

[0042] On theis shown schematically an aircraft with several propulsion rotors 7 provided with a propulsion system 9 according to one embodiment. In the example illustrated on the, the propulsion system 9 comprises four propulsion rotors 1 to 4 distributed on a circle propulsion rotors in dotted line arranged concentrically around a center of symmetry 8. The propulsion rotors 1 to 4 form two pairs of propulsion rotors. The propulsion rotors within the same pair of propulsion rotors are symmetrically opposed with respect to the center of symmetry 8. The first pair of propulsion rotors comprises rotors 1 and 4, and the second pair of propulsion rotors comprises rotors 2 and 3. It is also envisaged to provide more than four rotors.As seen in the, in the case of eight rotors 1, 1a, 2, 2a, 3, 3a, 4, 4a, rotors 1, 2, 3 and 4 are grouped respectively with rotors 1a, 2a, 3a and 4a, with rotors 1a and 4a symmetrically opposed with respect to the center of symmetry 8, and rotors 2a and 3a symmetrically opposed with respect to the center of symmetry 8. Furthermore, the propulsion system 9 comprises a smart motor for each propulsion rotor 1, 1a, 2, 2a, 3, 3a, 4, 4a. It is also envisaged for the aircraft 7 to comprise a single pair of propulsion rotors, or exactly three pairs of propulsion rotors, or at least four pairs of propulsion rotors. Furthermore, the smart engine 10 disclosed herein could also be used in a single propulsion engine aircraft or in an aircraft having an even or odd plurality of propulsion engines.

[0043] While the visible propulsion rotor arrangement is suitable for vertical takeoff and landing and / or rotary wing applications, schematically represents a fixed-wing aircraft 7a, with one, two, three, four, five, or even more propulsion rotors 1, 2, 3, …, X-1, X. Each engine may be identical to one of the engines visible in.

[0044] Those skilled in the art will understand that an engine according to the disclosure could be used in any propulsion / motor or non-propulsion application, in any aircraft / vehicle or non-vehicular machine.

[0045] In the case of an application with access to ground – for example, a non-flying machine – the common voltage reference for the smart motor assemblies is ground. In the case of an application without access to ground – for example, in an aircraft – the common voltage reference for the smart motor assemblies is the reference voltage used in the electrical system(s) of the aircraft (or other application).

[0046] A cross-sectional view of an intelligent motor 10 according to a first embodiment is shown schematically.

[0047] The smart motor 10 illustrated in the comprises an electromechanical converter 12 having a rotating part defining an axial direction DA and a radial direction DR. The is a sectional view along a plane comprising the axial direction DA and the radial direction DR.

[0048] A transmission shaft 13 is arranged towards a first end 201 of the motor 10 in the axial direction DA.

[0049] The smart motor 10 comprises an impeller 14 mounted on a cooling rotor 9 surrounding a cooling stator 99. The cooling rotor 9 and the cooling stator 99 are arranged towards a second end 202 of the smart motor 10 in the axial direction DA.

[0050] The intelligent motor 10 comprises electrical filtering means 16, an electronic control unit 18, and a housing 20, or casing inside which the electromechanical converter 12, the electronic control unit 18 and the filtering means 16 are housed.

[0051] The housing 20 has a hollow, substantially cylindrical or truncated cone shape, with, in the embodiment illustrated in the, a circular section. The axis of revolution of the housing 20 can be confused with the axis of rotation of the electromechanical converter 12 which is confused with the axis of rotation of the transmission shaft 13.

[0052] The axis of rotation of the transmission shaft 13 can be confused with the axis of rotation of the impeller 14.

[0053] In the axial direction DA, the housing 20 is closed towards the first end 201 by a cover 22, and towards the second end 202 by the impeller 14.

[0054] The smart motor 10 comprises a cooling device 24 which cooperates with the impeller 14 and the housing 20 to cool the various components of the smart motor 10 and in particular the electromechanical converter 12.

[0055] The cooling device 24 includes a cooling casing 245 disposed around the housing 20, thereby defining a cooling stream 248 disposed radially between an outer radial surface 203 of the housing 20 and an inner radial surface of the cooling casing 245. The terms "inner" and "outer", and "inner" and "outer" are used herein with reference to the radial direction DR in the smart motor 10.

[0056] The rotation of the impeller 14 generates and feeds an air flow F into the cooling stream 248. For example, the flow can enter the stream 248 through the second end 202 of the smart motor 10, passing through the blades 140 of the impeller 14, and can exit the stream through the first end 201 of the smart motor 10, passing through the cover 22.

[0057] The cooling device 24 comprises a set of fins 240 extending radially outward from the outer radial surface 203 of the housing 20, at a position in the axial direction DA between the first 201 and second 202 ends. The set of fins 240 forms a radiator allowing heat exchange between the fins 240 and an air flow F passing through the fins 240 of the cooling device 24. In this case, the set of fins is located at the stator 122 of the smart motor 10, and thus allows the stator 122 to be cooled.

[0058] In one variant, the smart engine could not include impellers and a cooling casing in order to reduce the mass of the smart engine. The smart engine would then be cooled by the airflow generated by the propulsion rotor of the aircraft, the propulsion rotor conventionally consisting of a propeller mechanically linked to the rotation shaft of the smart engine. In another variant, the smart engine could include an impeller directly driven by the shaft 13, without the need for cooling rotor torque and cooling stator.

[0059] In the embodiment illustrated in which represents a so-called "axial" configuration of the intelligent motor 10, the intelligent motor 10 comprises a housing 20 comprising a cooling device 24, a driving part comprising the electromechanical converter 12 and the transmission shaft 13, an electronic part comprising in particular the electrical filtering means 16 and the control unit 18. The electronic part is arranged between the electromagnetic converter 12 and the second end 202, for example between the bladed wheel 14 and the driving part in the axial direction DA.

[0060] The drive part is supported in the housing 20 by a conical structure 98 extending axially towards the second end 202 from the first end 201 and radially from the shaft 13 towards an internal radial surface 204 of the housing 20. At the shaft 13, the structure 98 comprises one or more bearings 97A, 97B.

[0061] Structure 98 separates the drive portion and the electronic portion. However, as seen in, structure 98 may include one or more perforations to reduce its weight.

[0062] The smart motor 10 comprises an inner wall 15 extending axially towards the first end 201 from the cooling stator 99 and radially from the cooling stator 99 towards the inner radial surface 204 of the housing 20. A first portion 15A of the inner wall 15 is fixed to the inner radial surface 204 of the housing 20, and surrounds a disc, extending radially towards the axial direction DA. A second portion 15B of the inner wall 15 is arranged inside the cooling stator 99 and fixed to the first portion 15A of the inner wall 15. The electromechanical converter 12 is arranged inside the housing 20 downstream of the first portion of the inner wall 15. The electrical filtering means 16 and the electronic control unit 18 of the electronic part are arranged upstream of the electromechanical converter 12.The terms "upstream" and "downstream" are used herein in reference to the direction of flow of the cooling airflow represented by arrow F on the.

[0063] The electronic control unit 18 comprises a static electrical converter 180 configured to power the electromechanical converter 12.

[0064] The electrical converter 180 is fixed to the first part 15A of the internal wall 15, and disposed between the disc and the second end 202.

[0065] The electrical converter 180 comprises, in the embodiment illustrated in the, six power electronic units 1800 arranged together on the first portion 15A of the inner wall 15 to form a hollow cylinder with a hexagonal base coaxial with the shaft 13.

[0066] In a variant where the electrical converter would comprise three, four, five, seven, or eight – or even more – electronic power units 1800, they would form a regular polygon coaxial with the shaft 13. If it comprised two electronic power units 1800, they would be on either side of the shaft, and coplanar with its axis of rotation.

[0067] The intelligent motor 10 comprises as many cooling devices 25 as there are electronic power units 1800. The cooling devices 25 are arranged on the first part 15A of the inner wall, at the same position in the axial direction DA as the electronic power units 1800, so that their fins extend into the vein 248.

[0068] The filtering means 16 comprise an electronic filtering card 160 on which capacitors 162 are mounted. The electronic filtering card 160 is fixed to the disc, and arranged between the disc and the structure 98.

[0069] In the embodiment illustrated in the, the capacitors 162 are arranged to create a polygonal shape allowing them to be inserted between the housing 20 and the shaft 13. The same applies when the motor 10 comprises two capacitors (diametrically opposed relative to the axis of rotation of the shaft 13), or three, four, five, six, seven, eight, or more (regular polygonal shapes coaxial with the shaft 13).

[0070] Furthermore, the electronic control unit 18 comprises an electronic control card 182 configured to control the operation of the electromechanical converter 12.

[0071] The intelligent motor 10 comprises an electronic supervision card 26 housed inside the housing 20 and in communication with the electronic control card 182. The electronic supervision card extends in a radial plane comprising the radial direction DR and orthogonal to the axial direction DA. The electronic supervision card 26 is arranged opposite the second part 15B of the internal wall 15, between the electrical converter 180 and the second part 15B of the internal wall 15.

[0072] In this axial configuration, the cooling device 24 is shared between the electromechanical converter 12 and the electronic part of the smart motor 10 (for example between the electromechanical converter 12, the filtering means 16 and the electronic control unit 18). The cooling air flow F delivered by the blades 140 of the impeller 14 circulates along the external radial surface 203 of the housing 20 and communicates fluidically with the fins of the cooling devices 24, 25. The housing 20 recovers both the heat generated by the electromechanical converter 12 and the heat generated by the electronic part, in particular by the power converter 180, and transfers the calories to the cooling air flow F in particular via the cooling devices 24, 25. The air flow F then evacuates the calories from the smart motor 10.

[0073] The electromechanical converter 12 of the intelligent motor 10 may be a synchronous machine. The electromechanical converter 12 comprises a rotor 121 with permanent magnets and a stator 122. As illustrated in the, the stator is provided with a first set 123 of at least three phases, the coils 1230 of which are electrically coupled in star, and a second set 124, with as many phases as the first set 123, and the coils 1240 of which are electrically coupled in star.

[0074] The electronic control unit 18 of the intelligent motor 10 comprises a control inverter 184 provided with as many independent control arms 1840 as there are phases of the stator of the electromechanical converter. Each control arm 1840 is configured to control a phase 123, 124 of the stator 122 of the electromechanical converter 12. The inverter 184 is configured to control each phase of the stator by its own control arm.

[0075] To ensure mechanical segregation between the assemblies 123, 124 of the stator, the coils 1230 of the first assembly 123 are wound and then the coils 1240 of the second assembly 124 can be wound after winding the coils 1230 of the first assembly 123.

[0076] The stator 122 comprises a toothed ring. Each coil 1230, 1240 of the stator can be wound around a single tooth of the toothed ring, which makes it possible to minimize the size of the stator 122, in particular the size of the head of each of the coils 1230 and 1240, or a series succession of several coils each wound around a single tooth of the toothed ring.

[0077] The rotor 121 has magnets arranged in a conventional radial configuration or a Halbach configuration to increase the specific torque of the smart motor 10.

[0078] When the motor 10 comprises only two sets 123, 124, the coils 1230 of the first set 123 may be arranged over a first angular range P1 of the stator extending over 180° mechanically and the coils 1240 of the second set 124 may be arranged over a second angular range P2 of the stator extending over 180° mechanically. Such an arrangement of the angular ranges is illustrated schematically in. The first angular range P1 is distinct from the second angular range P2, each angular range P1, P2 therefore covering a semicircle, in order to minimize – or even avoid – the magnetic coupling of the phases of different assemblies 123, 124, and / or to ensure mechanical segregation / geometric separation of the phases of different assemblies 123, 124. More generally, when the motor comprises N assemblies, there would be N distinct angular ranges each extending over (360 / N)° mechanically and collectively forming a circle.For example, N can be an integer equal to or greater than three.

[0079] It is also contemplated to provide multiple angular ranges per set. For example, in, the angular ranges P1a, P1b, P2a, P2b each extend over 90° mechanical and are arranged such that the ranges P1a and P1b, which correspond to the first set, are interspersed with the ranges P2a and P2b, which correspond to the second set. Larepresents a similar arrangement of three angular ranges P1a, P1b, P1c corresponding to the first set interspersed with three angular ranges P2a, P2b, P2c corresponding to the second set, each of the six ranges extending over 60° mechanical. More generally, when M ranges are provided for each set, they each extend over (180 / M)°, such that the ranges corresponding to the first set and the ranges corresponding to the second set collectively form a circle. For example, M may be an integer equal to or greater than three.

[0080] More generally, a range can extend over (360 / (N*M))° mechanicals, where N is the number of sets and M is the number of ranges per set.

[0081] The electronic control unit 18 comprises a current regulation module in each assembly 123, 124 independently of the other (or independently of the other) assembly(s) 124, 123, and a rotor speed regulation module 121.

[0082] The intelligent motor 10 comprises a connection interface connecting a high-voltage DC power supply bus to each of the arms 1840 of the inverter 184 of the electronic control unit 18. The connection interface comprises the filtering means 16 produced in the form of a capacitive decoupling stage provided with differential mode capacitors. In the embodiment illustrated in the, the connection interface is merged with the electronic filtering card 160.

[0083] The electronic control unit 180 is configured to measure a voltage difference between the neutral point of the star of the first set 123 and the neutral point of the star of the second set 124. For this purpose, the motor 10 may comprise an impedance Z12 (for example resistance, capacitance, inductance, or a combination thereof…) electrically coupling the neutral points of the stars of the first 123 and second 124 sets, and the electronic control unit 180 may be configured to measure the voltage VD12 across this impedance. The provision of an impedance Z12 between the neutral points makes it possible to limit the current between the stars of the sets. The impedance Z12 may be connected directly to the stator conductors, or indirectly connected to the stator conductors via wires, or other conductors.

[0084] In general, when two identical assemblies are driven in the same way, the assemblies are expected to behave in the same way. A deviation in their behavior, which typically means a problem with one or the other of the assemblies when driven in the same way, can be detected by the presence of a VD12 voltage difference between the neutral points of their stars, which exceeds a predetermined voltage threshold. The predetermined voltage threshold is higher than the normal voltage variations that can exist when assemblies driven in the same way behave in the same way.

[0085] The motor 10 may be configured (for example at its electronic control unit 180) to isolate the first 123 and second 124 assemblies from each other when it detects that this voltage difference VD12 exceeds the predetermined voltage threshold. For example, the predetermined threshold may correspond to a behavioral deviation beyond which a wire break or an open mode failure of the bridge arm supplying a coil, a circuit opening, a loss of an open-circuit transistor, a short circuit and / or significant degradation of the conductors could occur in a given assembly, or even a failure of an assembly, would generate a signal beyond the threshold, which makes it possible to signal the fault.

[0086] For example, in the context of an aircraft propulsion engine, the neutral point voltages of the two assemblies may differ by about 7 volts or less, whereas a fault in one of the assemblies would cause a difference of about 30 to 50 volts, or even more. The threshold may then be set between 7 and 50 volts, or between 7 and 30 volts, or between 10 and 30 volts, or between 13 and 25 volts, or between 13 and 20 volts, or between 13 and 17 volts. A relatively low threshold may allow faults to be detected earlier in their development, whereas a relatively high threshold may allow false alarms to be ruled out. Those skilled in the art will understand that such ranges for the threshold may also be used in contexts other than an aircraft.

[0087] Motor 10 can continue to use the non-failing assembly to drive shaft 13.

[0088] Schematically presents an electrical architecture according to a second embodiment of the motor visible in. This architecture differs from that visible in, by the presence of more than two assemblies in the stator 122.

[0089] When the motor 10 comprises more than two sets (each having as many phases as the first set 123), the neutral point of the star of the first set 123 is also electrically coupled to the neutral point of a star of a set other than the second set 124, the electronic control unit is configured to measure a voltage difference between the neutral points of the stars of the first set 123 and of this set other than the second set, the neutral point of the star of the second set 124 is electrically coupled to the neutral point of a star of a set other than the first set 123, and the electronic control unit is configured to measure a voltage difference between the neutral points of the stars of the second set 124 and of this set other than the first set.

[0090] For example, in, where the stator has three sets, of which the third 125 has as many phases (and coils 1250) as the first 123, the neutral point of the star of the third set 125 is electrically coupled to the neutral points of the stars of the first 123 and second 124 sets, and the electronic control unit is configured to measure the voltage VD13 between the neutral points of the stars of the first 123 and third 125 sets, and to measure the voltage VD23 between the neutral points of the stars of the third 125 and second 124 sets. There are also impedances Z13, Z23 between these neutral points to facilitate the detection of these respective voltages VD13, VD23.

[0091] In general, the inverter 184 includes as many independent control arms 1840 as there are phases of the set of stator assemblies.

[0092] More generally, and as seen in, when the stator 122 comprises at least three assemblies, each neutral point of each star of each assembly is electrically coupled to at least two neutral points of two stars of two other assemblies of the stator 122, and the electronic control unit 18 is configured to measure the voltage differences between the neutral point and each of the neutral points to which it is coupled.

[0093] When the motor 10 comprises at least three assemblies, measuring voltage differences between the neutral points of the stars of the assemblies is sufficient to determine a behavioral deviation between two assemblies controlled in the same way, and to identify which assembly would be affected by a fault. Indeed, when an assembly is affected by a fault, voltages will be detected between the neutral point of its star and the neutral points of the stars to which its neutral point is electrically coupled, and these voltages will exceed the chosen threshold.

[0094] When the motor 10 comprises only two sets, the voltage difference measurements may be supplemented by other measurements to determine a deviation in behavior when the sets are controlled in the same way. For example, the electronic control unit may be configured to measure the voltage at each terminal of each phase of the first 123 and second 124 sets, and to compare them to a divergence threshold. When the voltage between the neutral points exceeds its voltage threshold, and the voltage between two phases of the same set exceeds the divergence threshold, the motor 10 may signal a fault in the set corresponding to the divergent phases.

[0095] It is also envisaged to do the same for each phase of each assembly when the engine 10 comprises more than two assemblies, although this is not essential, when the engine 10 comprises at least three assemblies, to be able to detect faults at the level of a given assembly.

[0096] The presentation thus provides an intelligent motor architectural solution allowing both to improve the mass power of the motor for applications requiring a light, powerful motor including its power and control electronics, and to guarantee the supply of mechanical torque in the event of a failure of the voltage inverter arm of a star of a stator for an intelligent motor.

[0097] Although the motor 10 is shown to have its control unit within the housing, it is also contemplated to locate the control unit outside the housing, for example, to facilitate integration of the motor 10 into confined spaces.

[0098] The engine 10 has been presented in the context of an aircraft propulsion engine. It is also contemplated that an engine as described herein may be used as an electromechanical flight control actuator motor, as an electromechanical landing gear movement actuator motor, as a pump or fan motor – for example for critical applications (cockpit ventilation, hydraulic pump, fuel pump), or for any other application where operational safety is a key characteristic.

[0099] Furthermore, it is envisaged to use such an engine outside the aerospace field. Many other applications can be envisaged, while remaining within the scope of the presentation.

Claims

Intelligent motor (10) comprising:- an electromechanical converter with permanent magnets (12); and- an electronic control unit (18);the electromechanical converter (12) comprising:- a rotor (121) with permanent magnets; and- a stator (122) comprising:- a first assembly (123) comprising at least three phases electrically coupled to each other in a star configuration;- a second assembly (124) comprising as many phases as the first assembly, the phases of the second assembly being electrically coupled to each other in a star configuration; and- an impedance between the neutral points of the stars of the first and second assemblies;said electronic control unit comprising a control inverter (184), comprising as many independent control arms (1840) as there are phases of the first assembly and as many independent control arms as there are phases of the second assembly;the control inverter being configured to control each phase of the first set and each phase of the second set by its own control arms; the electronic control unit being configured to measure a voltage difference (VD12) between neutral points of the stars of the first and second sets with respect to a voltage reference common to said sets.; A smart motor (10) according to any preceding claim, configured to isolate the first and second sets from each other in response to the voltage between the neutral points of their stars exceeding a voltage threshold. The smart motor (10) of claim 2, wherein the voltage threshold is equal to or greater than seven, ten, or thirteen volts, and less than or equal to fifty, thirty, twenty-five, twenty, or seventeen volts. Smart motor (10) according to claim 2 or 3, configured to measure the voltage at each terminal of each phase of the first and second sets, and to signal a fault in a given set in response to a difference between the voltages of two of its phases exceeding a divergence threshold. Smart motor (10) according to any one of the preceding claims, wherein:the stator comprises at least one set other than the first and second sets, comprising (each) as many phases as the first set, electrically coupled to each other in star, the voltage reference being common to the first and second sets and to said set(s) other than the first and second sets;the inverter further comprises as many independent control arms as there are phases of the (set of) set(s) other than the first and second sets;the inverter is further configured to drive each phase of the (set of) set(s) other than the first and second sets by its own control arm;the electronic control unit is further configured to:- measure a voltage difference between the neutral point of the star of the first set and the neutral point of the star of the (one) set(s) other than the first and second sets;- measure a voltage difference between the neutral point of the star of the second set and the neutral point of the star of the (one) set(s) other than the first and second sets with respect to the common reference.; A smart motor (10) according to any preceding claim, wherein said stator (122) comprises a series of teeth arranged in a circumferential direction of the stator, each phase comprising a coil – or a series of several coils – wound around a single tooth of the stator. A smart motor (10) according to any preceding claim, wherein the rotor (121) comprises Halbach configuration magnets. A smart motor (10) according to any preceding claim, wherein the stator (122) is divided into distinct angular ranges, the number of angular ranges of a stator corresponding to the number of stator assemblies, the angular range extending over an angle corresponding to the result of dividing 360° by the number of stator assemblies, or by an integer multiple of the number of stator assemblies. A smart motor (10) according to any preceding claim, wherein the electronic control unit (18) further comprises a current regulation module configured to regulate the current in the assemblies independently of each other, and a rotor speed regulation module (121). Smart motor (10) according to any one of the preceding claims, further comprising a connection interface connecting a high voltage DC power bus to each of the arms (1840) of the inverter (184) of the electronic control unit (18), the connection interface comprising a capacitive decoupling stage (16) provided with differential mode capacitors.

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