Hybrid motor vehicle with a plurality of powertrain units with a device and method for ensuring safety in the event of malfunctioning of the electric machines

Abstract

The invention relates to a hybrid motor vehicle (1) with several powertrain units (11, 12) controlled by a controller (26) able to instigate a reconfiguration of the powertrain units (11, 12) if it is observed that there is a lasting malfunctioning of an electric machine (15, 18) of one of the units, by starting the electric machine unaffected by the malfunctioning, coupling, commanding the stopping of the combustion engine of the affected unit or disengaging it from the gearbox of the affected unit, placing the gearbox of the affected unit into neutral, limiting the electrical power consumed by the unaffected electric machine, keeping the speed of the vehicle below a predetermined maximum speed and triggering warning displays, the controller (26) exiting the reconfiguration mode when it is observed that the fault has cleared, and re-establishing normal operation of the vehicle, the fault code being retained in memory for after-sales servicing purposes.

Description

[0001] DESCRIPTION

[0002] TITLE OF THE INVENTION: HYBRID MOTOR VEHICLE WITH MULTIPLE POWER ENGINES WITH A SAFETY DEVICE AND METHOD AGAINST ELECTRICAL MACHINE MALFUNCTIONS

[0003]

[0001] The present invention claims priority from French application No. 2409351 filed on 03.09.2024, the content of which (text, drawings and claims) is incorporated herein by reference.

[0004]

[0002] The invention relates to a hybrid motor vehicle comprising at least one front powertrain including a front gearbox for driving a front wheel assembly and a front electric machine connected to said front gearbox and associated with a front electric machine computer, and comprising at least one rear powertrain including a rear gearbox for driving a rear wheel assembly and a rear electric machine connected to said rear gearbox and associated with a rear electric machine computer, said at least one rear powertrain including a dog clutch system for said rear wheel assembly.

[0005]

[0003] The invention further relates to a method of controlling such a hybrid motor vehicle when detecting a fault in one of the electrical machines of this vehicle.

[0006]

[0004] The invention further relates to a computer program comprising program code instructions for executing the steps of this control method, when said program is running on a computer.

[0007]

[0005] The invention is in the field of safety for 4x4 hybrid vehicles with an electric machine at least on one powertrain, in particular the front powertrain.

[0008]

[0006] Document WO2023208779A1 describes a method for activating one of the electrical machines of an electric vehicle when another electrical machine in the vehicle is overheating, and for modifying the vehicle's propulsion principle. The vehicle's maximum speed can be limited when a certain overheating temperature is reached, and the driver is informed via the vehicle's display. The output power of the electrical machines is also limited so that the vehicle does not exceed this maximum speed. This involves a change in the vehicle's propulsion mode when a temperature problem is encountered by one of the vehicle's electrical machines, plus a means of disconnecting the transmission of the faulty machine, a speed limitation for the vehicle, and display means to alert the driver.

[0009]

[0007] Currently on 4x2 hybrid vehicles, when the powertrain supervisor receives information from the front electric machine computer indicating a malfunction in its operation for a given period of time, the powertrain supervisor is obliged to immobilize the vehicle on the side of the road, because the electric machine is in direct contact with the primary shaft of the gearbox, and therefore when the vehicle is moving, the rotor of the front electric machine is obliged to turn, so potentially, there may be generation of current in the front electric machine and risk of the front electric machine catching fire.

[0010]

[0008] Therefore, the powertrain supervisor initiates the following recovery procedure: the powertrain supervisor prohibits the starting of the front internal combustion engine, then the powertrain supervisor shuts down the operation of the front electric drive machine, the powertrain supervisor requests the opening of the clutch system of the front gearbox, to disengage the internal combustion engine from the gearbox, and the powertrain supervisor requests the illumination of the "STOP" light on the instrument panel, to warn the driver of a serious fault and the prohibition of using the vehicle, as long as the fault persists.

[0011]

[0009] It is therefore understood that if the front electric motor reports a fault preventing its use to the powertrain supervisor, the vehicle is immobilized, leaving the driver and passengers stranded. This situation remains problematic, but at least it provides assurance that the electric motor will not catch fire.

[0012]

[0010] The objective of the present invention is to remedy these drawbacks by proposing the creation of a user protection function in the event of a failure of an electrical machine, in particular the front electrical machine, of hybrid motor vehicles with several motor-powertrains, in particular with two motor-powertrains usually designated 4x4, with at least one electrical machine on at least one motor-powertrain, in particular on the front motor-powertrain.

[0013]

[0011] To achieve this objective, the invention proposes a new functional for all-wheel drive (AWD) applications, in particular for 4x4, 4x6 hybrid vehicles, or even those with more drive axles such as construction or exceptional transport vehicles.

[0014]

[0012] The invention develops a strategy to guarantee the safety of users and the vehicle without immobilizing the vehicle in the event that the computer of an electrical machine, in particular the front electrical machine, reports a fault prohibiting the use of this electrical machine, in particular the front electrical machine, on all-wheel drive vehicles.

[0015]

[0013] The aim is to guarantee the safety of users and the vehicle in the event of a failure of an electrical machine, particularly the front electrical machine, rendering this electrical machine unusable, while limiting the negative effects on users. Indeed, the goal is to avoid inconvenience to users and also to prevent an accident due to a sudden interruption of torque from the drive chain and an unexpected, sudden immobilization of the vehicle.

[0016]

[0014] To this end, the invention relates to a hybrid motor vehicle comprising at least one front powertrain including a front gearbox for driving a front wheel assembly and a front electric machine connected to said front gearbox and associated with a front electric machine control unit, and comprising at least one rear powertrain including a rear gearbox for driving a rear wheel assembly and a rear electric machine connected to said rear gearbox and associated with a rear electric machine control unit, said at least one rear powertrain including a dog clutch system for said rear wheel assembly, said hybrid motor vehicle comprising either at least one front internal combustion engine belonging to said at least one front powertrain and which is connected to said front gearbox via a front coupling means,or both said at least one front internal combustion engine and at least one rear internal combustion engine belonging to said at least one rear powertrain and which is connected to said rear gearbox via a rear coupling means, said hybrid motor vehicle comprising at least one controller arranged to control a first supervisor of said front powertrain and a second supervisor of said rear powertrain, or to directly control said front powertrain and said rear powertrain, said at least one controller being arranged to directly or indirectly control said front gearbox and said rear gearbox, said front electric machine and said rear electric machine, and each internal combustion engine comprising said hybrid motor vehicle,said at least one controller being arranged to detect malfunctions of said forward electrical machine and said rear electrical machine.

[0017]

[0015] According to the invention, said controller is arranged to detect a malfunction of said front electric machine or of said rear electric machine preventing the operation of said electric machine, and said controller, or said first supervisor or said second supervisor, is arranged to request said rear electric machine computer or respectively said front electric machine computer to start said rear electric machine or respectively said front electric machine, upon detection by said controller of said malfunction of said front electric machine or respectively said rear electric machine.

[0018]

[0016] Thanks to the invention, it is possible to ensure the safety of the vehicle and its occupants, and to prevent any abnormal rise in temperature in an electric traction machine of this vehicle.

[0019]

[0017] Advantageously, said controller is arranged to control the engagement of said clutch system when said controller detects a malfunction of said front or rear electric machine that prevents its operation.

[0018] Thus, it is certain that the defective electric machine will not be driven during the movement of the vehicle.

[0020]

[0019] Advantageously, said controller or said first supervisor or said second supervisor is arranged to open a front clutch located between said at least one front internal combustion engine and said front gearbox, or respectively a rear clutch located between said at least one rear internal combustion engine and said rear gearbox, or to request the shutdown of the internal combustion engine from the internal combustion engine control unit associated with said at least one front internal combustion engine or respectively with said at least one rear internal combustion engine, when said controller detects a malfunction of said front electric machine or of said rear electric machine preventing the operation of said electric machine.

[0021]

[0020] This configuration makes it possible to avoid the drive of the gearbox of the powertrain concerned by the malfunction of the electric machine.

[0022]

[0021] Advantageously, said controller or said first supervisor or said second supervisor is arranged to command the shifting of the gearbox to neutral to a gearbox computer associated with said front gearbox or respectively said rear gearbox, when the controller detects a malfunction of said front electric machine or said rear electric machine preventing the operation of said electric machine.

[0023]

[0022] This avoids the transmission of torque from the electric machine or the internal combustion engine of the powertrain concerned by the malfunction to its running gear, and the transmission of torque during the movement of the vehicle to the electric machine or the internal combustion engine of the powertrain concerned.

[0024]

[0023] Advantageously, said controller is arranged to limit the electrical power drawn by said rear electric machine or respectively by said front electric machine to a predetermined power limit, upon detection by said controller of a malfunction of said front electric machine or said rear electric machine preventing its operation.

[0024] This reduces the performance of the vehicle, which is in a degraded safety mode.

[0025]

[0025] Advantageously, said controller is arranged to activate a vehicle speed blocking function to prevent said hybrid motor vehicle from exceeding a predetermined maximum speed, when said controller detects a malfunction of said front electric machine or said rear electric machine prohibiting the operation of said electric machine.

[0026]

[0026] Thus, the speed of the vehicle is reduced, which is in a degraded safety mode.

[0027]

[0027] Advantageously, said controller is arranged to control the illumination of a service warning light on the dashboard of said hybrid motor vehicle to direct the user to after-sales service, and / or to control the illumination of a vehicle speed limit warning light on the dashboard of said hybrid motor vehicle to inform the user of the existence of a maximum imposed speed, and / or to record in a memory of said controller at least one fault code informing after-sales service of the existence of a problem related to a loss of communication between, on the one hand, a gearbox control unit associated with said front gearbox or respectively said rear gearbox, and on the other hand, said controller and / or said first supervisor or respectively said second supervisor,upon detection by said controller of a malfunction of said front or rear electrical machine preventing the operation of said electrical machine.

[0028]

[0028] Thus, the vehicle user is immediately informed of the existence of a malfunction and the automatic switching of his vehicle into a degraded safety mode, and the information relating to this malfunction is stored for later use by the after-sales service.

[0029]

[0029] The invention further relates to a method for controlling such a hybrid motor vehicle comprising a fault detection step in which said controller and / or said first supervisor or said second supervisor detects a malfunction of said front electric machine or respectively of said rear electric machine preventing the operation of said electric machine for a period exceeding a first predetermined period, and a reconfiguration step in which said controller reconfigures said at least one front powertrain and said at least one rear powertrain, where said reconfiguration step comprises elementary actions, in a first elementary action said controller requests the computer of the electric machine not concerned by the malfunction to start the electric motor of the corresponding powertrain,In a second elementary action, said controller operates the engagement of said rear dog clutch system; in a third elementary action, either said controller opens the clutch of the powertrain affected by the malfunction so that the corresponding internal combustion engine no longer drives the gearbox of the corresponding powertrain, or said controller commands the shutdown of the internal combustion engine of the powertrain affected by the malfunction; in a fourth elementary action, said controller puts the gearbox of the powertrain affected by the malfunction into neutral; in a fifth elementary action, said controller limits the electrical power drawn by the electric machine of the rear powertrain not affected by the malfunction below a limit power level.In a sixth elementary action, the controller requests a vehicle speed-locking function to prevent the vehicle from exceeding a predetermined maximum speed, and in a seventh elementary action, the controller triggers at least one alarm and safety display.

[0030]

[0030] This method ensures the limitation of the effects of the malfunction of an electric traction machine, and allows the vehicle to be put into a degraded safety mode allowing it to reach a safe location for the safety of the vehicle's occupants.

[0031]

[0031] Advantageously, when the supervisor of said powertrain concerned by the malfunction observes the permanent disappearance of the fault, the computer of the electrical machine which was implicated by the fault sends the supervisor or said controller the information of the restoration of the normal behavior of the electrical machine concerned, and said controller exits the reconfiguration mode and restores the normal operation of the vehicle, and the fault code is kept in a memory of said controller until the next after-sales service of said vehicle.

[0032]

[0032] Thus a subsequent restart is possible, but all information relating to the malfunction and its treatment is stored in memory for its subsequent highlighting by the after-sales service.

[0033]

[0033] The invention further relates to a computer program comprising program code instructions for executing the steps of this control method, when said program is running on a computer.

[0034]

[0034] It is therefore possible to integrate the new safety function according to the invention into an existing vehicle comprising a driving computer.

[0035]

[0035] The invention will be further detailed by describing non-limiting embodiments, and based on the accompanying figures illustrating variants of the invention, in which:

[0036] - [Fig.1] illustrates in block diagram form a hybrid powertrain in which the electric motor does not directly drive the wheels, comprising both an electric machine and a thermal engine, in the example of a front axle;

[0037] - [Fig.2] schematically illustrates, similarly to [Fig.1], a rear-wheel hybrid powertrain comprising a thermal engine;

[0038] - [Fig.3] schematically illustrates, similarly to [Fig.1], a rear-wheel drive hybrid powertrain, devoid of a thermal engine;

[0039] - [Fig.4] schematically illustrates, in partial and simplified top view, the openwork arrow indicating the front of the vehicle, different components of a hybrid motor vehicle comprising a front axle according to [Fig.1] and a rear axle according to [Fig.3], this rear axle being equipped with a classic dog clutch system on 4x4 vehicles;

[0040] - [Fig.5] illustrates in the form of a block diagram a sequence of elementary actions during a reconfiguration phase of the two powertrain groups of the vehicle of [Fig.4] after the finding of a lasting malfunction of one of its electric traction machines.

[0041]

[0036] The invention relates to a hybrid motor vehicle 1, comprising a plurality of drive trains each comprising a powertrain, in particular a front powertrain 11, and a rear powertrain 12, with at least one electric machine on at least two powertrains, in particular a front electric machine 15 on the front powertrain 11, and a rear electric machine 18 on the rear powertrain 12.

[0042]

[0037] The invention is illustrated, in a non-limiting way, in this case where the vehicle 1 comprises a front powertrain 11, visible in [Fig.1] and [Fig.4], comprising a front electric machine 15, and comprises a rear powertrain 12, visible in [Fig.2] or [Fig.3], and in [Fig.4], comprising a rear electric machine 18.

[0043]

[0038] The architecture of an MHEV or "mild-hybrid" (from the English "mild hybrid electric vehicle") powertrain is schematically illustrated in [Fig. 1], that is, a hybrid vehicle in which the electric motor does not directly drive the wheels. Such an MHEV powertrain, here a front powertrain 11, comprises a front internal combustion engine 321, to which is associated a front electric motor 15 powered by at least one battery 23, which assists the internal combustion engine 321 during acceleration phases, thereby reducing the vehicle's fuel consumption 1 and CO2 emissions.

[0044]

[0039] The front powertrain 11 includes a front supervisor 301, itself controlled by a controller 26 at the vehicle level 1, and which controls various computers:

[0045] - A traction battery computer, which manages the operation of the traction power battery;

[0046] - A gearbox control unit, which manages the operation of the gearbox;

[0047] - An electric machine computer, here a front 24 computer of the front 15 electric machine, which manages the operation of the front 15 electric machine; - A thermal engine computer of the front 321 powertrain, which manages the operation of the 321 thermal engine.

[0048]

[0040] The front 301 supervisor of the front powertrain 11 supervises the proper functioning of all these computers, and coordinates the actions of all these computers.

[0049]

[0041] [Fig.1] shows the mechanical architecture of this powertrain before 11. For simplification, this powertrain is illustrated with a single example of each component; it is understood that the invention also applies to a powertrain comprising several thermal engines, or several electric machines, or other.

[0050]

[0042] A front thermal engine 321 includes the thermal engine control unit, controlled by the front supervisor 301, and is connected by a front coupling 331 to a front gearbox 16, to filter the thermal engine's acyclicity in order to reduce gearbox noise (sniffing) and the buzzing inside the vehicle which originates from the engine acyclicity transmitted to the vehicle's wheels, 11.1 and 11.2 for this front axle.The front coupling 331 includes in particular a dual-mass flywheel: a first flywheel 34 fixed to the crankshaft of the front internal combustion engine 321, and comprising a ring (toothed or notched or pulley) arranged to cooperate with a front electric starter 381, and a second flywheel 36, equipped with weights also called pendulums 37, this second flywheel 36 being connected to the first flywheel 34 by at least one spring 35, or by a combination of stops of a ball bearing and springs, this arrangement making it possible to compensate for irregularities in the engine in torque variation, by constituting a damping device absorbing excessive variations in kinetic energy, thus reducing the torsional stresses on the transmission to which the second flywheel 36 is indirectly connected.

[0051]

[0043] This front coupling 331 is connected to a front clutch mechanism 391, which is controlled by the front supervisor 301. When the clutch is open, it allows the front internal combustion engine 321 to be isolated when the front supervisor 301 decides that the optimum is to drive in pure electric mode (or when the user requests pure electric mode) without having to overcome the friction torque of the front internal combustion engine 321. This front clutch 391 also allows the front internal combustion engine 321 to be started with a starter motor or a starter-generator. When the vehicle 1 is running in hybrid or pure internal combustion mode, the front clutch 391 is closed.

[0052]

[0044] Downstream of this forward clutch 391 is the forward electric machine 15, which is controlled by the forward supervisor 301, and which is connected to the input of a forward gearbox 16 by a transmission element such as a chain (alternatively this forward electric machine 15 can be connected to the input of the forward gearbox 16 by a cascade of gears or a belt or similar).

[0053]

[0045] This front electric machine 15 is sufficiently powerful to drive the vehicle 1 in pure electric traction, and it also allows the traction batteries 23 and / or the service battery to be recharged. This front electric machine 15 can operate as an electric motor during vehicle traction phases, and as an alternator during vehicle deceleration phases and / or battery recharging phases.

[0054]

[0046] Next comes the front gearbox 16, whose gearbox computer is controlled by the front supervisor 301, this front gearbox 16 can be a dual clutch gearbox (DCT gearbox), or a piloted gearbox, or even an automatic gearbox.

[0055]

[0047] [Fig.1] shows a forward 16 dual clutch gearbox, with a first clutch and a second clutch, whose respective primary shafts are arranged to drive the respective secondary shafts, attacking the same differential at the gearbox output.

[0056]

[0048] Alternatively, if the forward gearbox 16 is a simple pilot gearbox or an automatic gearbox, it has only one clutch between the gearbox teeth and the forward electric machine 15, there may even be no clutch between the forward electric machine 15 and the gearbox teeth.

[0057]

[0049] Downstream of the differential of the front gearbox 16, the front transverse transmissions 13 drive the front wheels 11.1 and 11.2 of the vehicle 1.

[0058]

[0050] [Fig. 2] illustrates a rear powertrain 12 comprising a front supervisor 302, itself controlled by the controller 26. Its architecture is similar to that of the front powertrain 11 of [Fig. 1]: a rear internal combustion engine 322 includes the internal combustion engine control unit, controlled by the rear supervisor 302, and is connected by a rear coupling 332 to a rear gearbox 19. The rear coupling 332 is connected to a rear clutch mechanism 392, which is controlled by the rear supervisor 302, and which, when the clutch is open, allows the rear internal combustion engine 322 to be isolated. Downstream of this rear clutch 392, a rear electric machine 18 is controlled by the rear supervisor 302 and is connected to the input of a rear gearbox 19. Downstream of the differential of the rear gearbox 19, rear transverse transmissions 14 drive the rear wheels 12.1 and 12.2 of vehicle 1.

[0059]

[0051] [Fig. 3] illustrates a rear powertrain 12 for a vehicle 1 comprising a single internal combustion engine, mounted on the front powertrain 11 in this non-limiting example. As before, this rear powertrain 12 includes a front supervisor 302, itself driven by the controller 26. The rear electric machine 18 is driven by the rear supervisor 302 and is connected to the input of the rear gearbox 19. Downstream of the differential of the rear gearbox 19, the rear transverse transmissions 14 drive the rear wheels 12.1 and 12.2.

[0060]

[0052] [Fig.4] illustrates, in simplified form, the architecture of a multi-powertrain hybrid AWD vehicle 1, for the particular and non-limiting case of a front powertrain 11 and a rear powertrain 12. A battery group 23, not detailed in the figure, supplies each electric machine 15, 18, of the vehicle 1. The controller 26 comprises, for each powertrain, front 11, rear 12, a front supervisor 301 as illustrated in [Fig.1], or respectively a rear supervisor 302 as illustrated in [Fig.2], [Fig.3], or the controller 26 constitutes a single supervisor managing each of the powertrains of the vehicle 1.

[0061]

[0053] In a non-limiting example, the vehicle 1 of [Fig. 4] comprises the front powertrain 11 of [Fig. 1], including a heat engine, and the rear powertrain 12 of [Fig. 3], without a heat engine.

[0054] The front powertrain 11 includes a front electric machine 15, a front reduction gear or gearbox 16, and drives front wheels 11.1 and 11.2.

[0062]

[0055] It is important to monitor the front electric machine 15, which is directly connected to the primary shaft of the front gearbox 16, because, as a result, when the vehicle is moving, the rotor of the front electric machine 15 is forced to turn, so potentially, there may be generation of current in the front electric machine 15, and risk of the front electric machine 15 catching fire, which must be avoided at all costs.

[0063]

[0056] The rear powertrain 12 includes a rear electric machine 18, a rear reduction gear or gearbox 19, and drives rear wheels 12.1 and 12.2. This rear powertrain 12 further includes a dog clutch system 21 connecting the rear powertrain to the rear axles 12.1 and 12.2. The rear dog clutch system 21 is very important because it prevents the rear powertrain 12 from rotating when the vehicle 1 is operating in 4x2 mode, thereby reducing vehicle friction losses and saving energy for vehicle traction.

[0064]

[0057] The strategy is based on the following principle: if the supervisor 301, 302, of the powertrain group 11, 12, receives from the computer of the respective electric machine 15, 18, of this group 11, 12, information that this electric machine is experiencing a technical problem, rendering this electric machine non-functional, the computer of the electric machine concerned sends to the supervisor 301, 302, of the respective powertrain group 11, 12, an unavailability information "not available", therefore a non-availability of the operation of the electric machine concerned 15, 18, for a period greater than a first duration D1 (with the first duration D1 calibrable during the development of this function, but preferably the order of magnitude is at least a first duration D1 greater than or equal to 300 milliseconds).

[0065]

[0058] Alternatively, the engagement conditions can also be extended to the new reconfiguration of the at least two powertrains 11, 12, comprising the vehicle 1, so that the powertrain supervisor receives only empty frames of information on the CAN network (from the English "controller area network"), which is a multiplexed data bus, from the computer of the electric machine 15, 18, concerned by the unavailability, the supervisor 301, 302, of the powertrain concerned 11, 12, detects a malfunction of the computer of the respective electric machine 15, 18 concerned by the unavailability, or detects a break in the CAN network between the computer of this electric machine and the powertrain supervisor.

[0066]

[0059] In this case where the supervisor 301, 302, of the powertrain 11, 12, detects a non-availability of the electric machine 15, 18, concerned by the unavailability for more than the first duration D1, the supervisor 301, 302, of this powertrain 11, 12, triggers the new reconfiguration function developed within the framework of the invention.

[0067]

[0060] To this end, according to the invention, the controller 26 is arranged to detect a malfunction of the front electric machine 15 or the rear electric machine 18, preventing the operation of that electric machine. And the controller 26, or the first supervisor 301 or the second supervisor 302, or each of them, is arranged to request the rear electric machine computer 25 or respectively said front electric machine computer 24 to start the rear electric machine 18 or respectively the front electric machine 15, upon detection by the controller 26 of such a malfunction of the front electric machine 15 or respectively the rear electric machine 18.

[0068]

[0061] More particularly, the controller 26 or the first supervisor 301 or the second supervisor 302 is arranged to open a front clutch 391 located between at least one front thermal engine 321 and the front gearbox 16, or respectively a rear clutch 392 located between at least one rear thermal engine 322 and the rear gearbox 19, or to request the shutdown of the thermal engine from a thermal engine control unit associated with at least one front thermal engine 321 or respectively with at least one rear thermal engine 322, when the controller 26 detects a malfunction of the front electric machine 15 or the rear electric machine 18 preventing the operation of this electric machine.

[0062] More particularly, the controller 26 or the first supervisor 301 or the second supervisor 302 is arranged to command the shifting of the gearbox to neutral to a gearbox computer associated with the front gearbox 16 or respectively the rear gearbox 19, when the controller 26 detects a malfunction of the front electric machine 15 or the rear electric machine 18 preventing the operation of this electric machine.

[0069]

[0063] More particularly, the controller 26 is arranged to limit the electrical power taken by the rear electric machine 18 or respectively by the front electric machine 15 under a predetermined power limit, when the controller 26 detects a malfunction of the front electric machine 15 or the rear electric machine 18 prohibiting the operation of this electric machine.

[0070]

[0064] More specifically, the controller 26 is arranged to activate a vehicle speed blocking function to prevent the hybrid motor vehicle 1 from exceeding a predetermined maximum speed, when the controller 26 detects a malfunction of the front electric machine 15 or the rear electric machine 18 prohibiting the operation of this electric machine.

[0071]

[0065] More particularly, the controller 26 is arranged to control the illumination of a service warning light on the dashboard of the hybrid motor vehicle 1 to direct the user to after-sales service, and / or to control the illumination of a vehicle speed limit warning light on the dashboard of the hybrid motor vehicle 1 to inform the user of the existence of a maximum imposed speed, and / or to record in a memory of the controller 26 at least one fault code informing after-sales service of the existence of a problem related to a loss of communication between, on the one hand, a gearbox control unit associated with the front gearbox 16 or respectively the rear gearbox 19, and, on the other hand, the controller 26 and / or the first supervisor 301 or respectively the second supervisor 302,upon detection by the controller 26 of a malfunction of the front electric machine 15 or the rear electric machine 18 preventing the operation of this electric machine.

[0066] This reconfiguration strategy is described here, without limitation, for the general case of a hybrid motor vehicle 1 with two powertrains 11, 12, of the 4x4 type according to [Fig. 4], its principle is naturally extendable to a number of powertrains greater than 2.

[0072]

[0067] In this new function of reconfiguring the front powertrain 11 and the rear powertrain 12, the controller 26 initiates various elementary actions, the following presentation of which is given in the example of the unavailability of the front electric machine 15 of the front powertrain 11:

[0073] - First elementary action 100: the controller 26 asks the rear computer 25 of the rear electric machine 18 to start the rear electric motor 18 of the rear powertrain 12;

[0074] - Second elementary action 200: the controller 26 controls the dog engagement of the rear dog clutch system 21 of the rear powertrain 12;

[0075] - Third elementary action 300: the controller 26 opens the clutch 39 of the front powertrain so that the front internal combustion engine 32 no longer drives the front gearbox 16 of the front powertrain 11, or, as an alternative variant, the controller 26 commands the shutdown of the internal combustion engine 321 of the front powertrain 11;

[0076] - Fourth elementary action 400: the controller 26 puts the front gearbox 16 of the front powertrain 11 in neutral, so that this front gearbox 16 does not transmit torque from the front electric machine 15 of the front powertrain 11 to the front wheels 11.1 and 11.2, nor torque from the front internal combustion engine 321 of the front powertrain 11 to the front wheels 11.1 and 11.2, nor does the gearbox transmit torque from the wheels of vehicle 1 to the front electric machine 15 of the front powertrain 11 or from the wheels of vehicle 1 to the front internal combustion engine 321 of the front powertrain 11;

[0077] - Fifth elementary action 500: the controller 26 limits the electrical power taken by the rear electric machine 18 of the rear powertrain 12 to a limit power level "Plim" to reduce the performance of the vehicle 1, because the vehicle is still in a degraded mode, and the use of a safety degraded mode is necessary;

[0078] - Sixth elementary action 600: the controller 26 requests a BVV function (which means "vehicle speed lock") to prevent vehicle 1 from exceeding a maximum vehicle speed "Vmax" because the vehicle is in a degraded mode, and the use of a safety degraded mode is required;

[0079] - Seventh elementary action 700: Controller 26 triggers at least one alarm and safety display, and requests the illumination of a "SERVICE" light on the dashboard, to warn the driver of a detected problem that needs to be diagnosed by the after-sales service, or / and Controller 26 also requests the display on the dashboard of a message indicating that the maximum speed of the vehicle is limited following the detection of a problem, to warn the driver that it is normal that he can no longer exceed a certain speed of the vehicle, or / and alternatively Controller 26 records a fault code in the memory of one of the vehicle's computers to help the after-sales service identify that the problem comes from a loss of communication between the gearbox computer and Controller 26.

[0080]

[0068] With the power limit level "Plim" calibrable in the controller 26 during the development of this new function, this maximum electrical power is notably, but not limited to, calibrated around 20 kW (but this value is calibrated according to the mass characteristics and coefficient of penetration in the air of the vehicle and the characteristics of the tires of the vehicle in question, therefore this calibration depends on the vehicle), the purpose of this power limitation is to prevent the vehicle from driving too fast in degraded mode (the speed of the vehicle must be less than a speed limit "Vlim" that the rear electric powertrain can accept, for example and not limited to Vlim = 120 km / h).

[0081]

[0069] With the maximum speed "Vmax" calibrated in the controller 26 during the development of this new function, this maximum vehicle speed is, in particular but not exclusively, calibrated to 120 km / h. Naturally, this maximum vehicle speed "Vmax" can take other values.

[0082]

[0070] Thus, in summary, this method of controlling such a hybrid motor vehicle 1 comprises a fault detection step in which the controller 26 and / or the first supervisor 301 or the second supervisor 302 detects a malfunction of the front electric machine 15 or respectively of the rear electric machine 18 prohibiting the operation of this electric machine, for a period greater than a first predetermined period, and a reconfiguration step in which the controller 26 reconfigures at least one front powertrain 11 and at least one rear powertrain 12.

[0083]

[0071] This reconfiguration step comprises elementary actions, in a first elementary action 100 the controller 26 requests the computer of the electric machine not concerned by the malfunction to start the electric motor of the corresponding powertrain, in a second elementary action 200 the controller 26 controls the engagement of the rear dog clutch system 21, in a third elementary action 300 either the controller 26 opens the clutch of the powertrain concerned by the malfunction so that the corresponding internal combustion engine no longer drives the gearbox of the corresponding powertrain, or the controller 26 commands the shutdown of the internal combustion engine of the powertrain concerned by the malfunction, in a fourth elementary action 400 the controller 26 puts the gearbox of the powertrain concerned by the malfunction into neutral,In a fifth elementary action 500, the controller 26 limits the electrical power drawn by the electric machine of the rear powertrain not affected by the malfunction below a limit power level; in a sixth elementary action 600, the controller 26 requests a vehicle speed-lock function to prevent vehicle 1 from exceeding a predetermined maximum speed; and in a seventh elementary action 700, the controller 26 triggers at least one alarm and safety display.

[0084]

[0072] Regarding the return to normal, if the control unit of the front electric machine 15 detects that the fault has disappeared, the control unit of the front electric machine 15 resumes sending the status frame of the front electric machine 15 to the supervisor controller 26, indicating that it is "available". This means that the behavior of the front electric machine 15 has been restored, and the powertrain supervisor then restores normal vehicle operation, exiting this new powertrain reconfiguration mode.

[0085]

[0073] In summary, when the supervisor of the powertrain concerned by the malfunction observes the permanent disappearance of the fault, the computer of the electric machine which was implicated by the fault sends the supervisor or the controller 26 the information of the restoration of the normal behavior of the electric machine concerned, and the controller 26 exits the reconfiguration mode and restores the normal operation of the vehicle, and the fault code is kept in a memory of the controller 26 until the next after-sales visit of the vehicle 1.

[0086]

[0074] However, fault codes stored in one or more of the vehicle's control units remain stored in the memory of one of the vehicle's control units. For example, the memory of an intelligent control unit can be used, but any other control unit memory can be used. Thus, during vehicle servicing, the service department can identify a specific fault in the history, and the service department then performs a check of the electrical system before 15.

[0087]

[0075] Naturally the operation is similar in the event of a malfunction of the rear electric machine 18. The principle is also applicable to a vehicle comprising several internal combustion engines attached to different powertrains.

[0088]

[0076] The invention further relates to a computer program comprising program code instructions for executing the steps of this control method, when this program is running on a computer.

[0089]

[0077] In summary, the invention makes it possible to guarantee the safety of users and the vehicle, even in the event of a failure of the front electrical machine.

[0090]

[0078] The new powertrain reconfiguration strategy is implemented when the control unit of an electric motor, particularly the front electric motor, experiences a failure that renders the electric motor unusable. This new reconfiguration of the powertrain's functionality, specifically the front powertrain, ensures passenger safety without immobilizing the vehicle and minimizing disruption to users.

Claims

DEMANDS 1. Hybrid motor vehicle (1) comprising at least one front powertrain (11) comprising a front gearbox (16) for driving a front wheel assembly (11.1, 11.2) and a front electric machine (15) connected to said front gearbox (16) and associated with a front electric machine control unit (24), and comprising at least one rear powertrain (12) comprising a rear gearbox (19) for driving a rear wheel assembly (12.1, 12.2) and a rear electric machine (18) connected to said rear gearbox (19) and associated with a rear electric machine control unit (25), said at least one rear powertrain (12) comprising a dog clutch system (21) for said rear wheel assembly (12.1, 12.2),said hybrid motor vehicle (1) comprising either at least one front internal combustion engine (321) belonging to said at least one front powertrain (11) and which is connected to said front gearbox (16) via a front coupling means (331), or both said at least one front internal combustion engine (321) and at least one rear internal combustion engine (322) belonging to said at least one rear powertrain (12) and which is connected to said rear gearbox (16) via a rear coupling means (332), said hybrid motor vehicle (1) comprising at least one controller (26) arranged to control a first supervisor (301) of said front powertrain (11) and a second supervisor (302) of said rear powertrain (12), or to directly control said front powertrain (11) and said rear powertrain (12),said at least one controller (26) being arranged to directly or indirectly control said front gearbox (16) and said rear gearbox (19), said front electric machine (15) and said rear electric machine (18), and each internal combustion engine (321, 322) comprising said hybrid motor vehicle (1), said at least one controller (26) being arranged to detect malfunctions of said front electric machine (15) and said rear electric machine (18), characterized in that said controller (26) is arranged to detect a malfunction of, said front electric machine (15) or said rear electric machine (18) prohibiting the operation of said electric machine, and in that said controller (26), or said first supervisor (301) or said second supervisor (302), is arranged to request said rear electric machine computer (25) or respectively said front electric machine computer (24) to start said rear electric machine (18) or respectively said front electric machine (15), upon detection by said controller (26) of said malfunction of said front electric machine (15) or respectively said rear electric machine (18).

2. Hybrid motor vehicle (1) according to claim 1, characterized in that said controller (26) is arranged to control the engagement of said engagement system (21), upon detection by said controller (26) of a malfunction of said front electric machine (15) or of said rear electric machine (18) prohibiting the operation of this electric machine.

3. Hybrid motor vehicle (1) according to claim 1 or 2, characterized in that said controller (26) or said first supervisor (301) or said second supervisor (302) is arranged to open a front clutch (391) located between said at least one front internal combustion engine (321) and said front gearbox (16), or respectively a rear clutch (392) located between said at least one rear internal combustion engine (322) and said rear gearbox (19), or to request the shutdown of the internal combustion engine from the internal combustion engine control unit associated with said at least one front internal combustion engine (321) or respectively with said at least one rear internal combustion engine (322), upon detection by said controller (26) of a malfunction of said front electric machine (15) or of said rear electric machine (18) preventing the operation of said electric machine.

4. Hybrid motor vehicle (1) according to any one of claims 1 to 3, characterized in that said controller (26) or said first supervisor (301) or said second supervisor (302) is arranged to command the shifting of the gearbox to neutral by a gearbox control unit associated with said front gearbox (16) or respectively said gearbox rear (19), when the said controller (26) detects a malfunction of the said front (15) or rear (18) electric machine prohibiting the operation of this electric machine.

5. Hybrid motor vehicle (1) according to any one of claims 1 to 4, characterized in that said controller (26) is arranged to limit the electrical power taken by said rear electric machine (18) or respectively by said front electric machine (15) below a predetermined power limit, when the controller (26) detects a malfunction of said front electric machine (15) or of said rear electric machine (18) prohibiting the operation of this electric machine.

6. Hybrid motor vehicle (1) according to any one of claims 1 to 5, characterized in that said controller (26) is arranged to activate a vehicle speed blocking function to prevent said hybrid motor vehicle (1) from exceeding a predetermined maximum speed, upon detection by said controller (26) of a malfunction of said front electric machine (15) or of said rear electric machine (18) prohibiting the operation of this electric machine.

7. Hybrid motor vehicle (1) according to any one of claims 1 to 6, characterized in that said controller (26) is arranged to control the illumination of a service warning light on the dashboard of said hybrid motor vehicle (1) to direct the user to after-sales service, and / or to control the illumination of a vehicle speed limit warning light on the dashboard of said hybrid motor vehicle (1) to inform the user of the existence of a maximum imposed speed, and / or to record in a memory of said controller (26) at least one fault code informing after-sales service of the existence of a problem related to a loss of communication between, on the one hand, a gearbox control unit associated with said front gearbox (16) or respectively said rear gearbox (19), and, on the other hand, said controller (26) and / or said first supervisor (301) or respectively said second supervisor (302),upon detection by said controller (26) of a malfunction of said, electric machine forward (15) or of said electric machine rear (18) prohibiting the operation of this electric machine.

8. A method for controlling a hybrid motor vehicle (1) according to any one of claims 1 to 7, comprising a fault detection step in which said controller (26) and / or said first supervisor (301) or said second supervisor (302) detects a malfunction of said front electric machine (15) or respectively of said rear electric machine (18) preventing the operation of said electric machine for a period exceeding a first predetermined period, and a reconfiguration step in which said controller (26) reconfigures said at least one front powertrain (11) and said at least one rear powertrain (12), wherein said reconfiguration step comprises elementary actions,In a first elementary action (100), said controller (26) requests the computer of the electrical machine not affected by the malfunction to start the electric motor of the corresponding powertrain; in a second elementary action (200), said controller (26) controls the engagement of said rear dog clutch system (21); in a third elementary action (300), either said controller (26) opens the clutch of the powertrain affected by the malfunction so that the corresponding internal combustion engine no longer drives the gearbox of the corresponding powertrain, or said controller (26) commands the shutdown of the internal combustion engine of the powertrain affected by the malfunction; in a fourth elementary action (400), said controller (26) puts the gearbox of the powertrain affected by the malfunction into neutral.In a fifth elementary action (500), said controller (26) limits the electrical power drawn by the electric machine of the rear powertrain not affected by the malfunction below a limit power level; in a sixth elementary action (600), said controller (26) requests a vehicle speed-lock function to prevent said vehicle (1) from exceeding a predetermined maximum speed; and in a seventh elementary action (700), said controller (26) triggers at least one alarm and safety display.

9. A control method according to claim 8, wherein, when the supervisor of said powertrain affected by the malfunction observes the permanent disappearance of the fault, the control unit of the electrical machine that was implicated by the fault sends the supervisor or said controller (26) the information that the normal behavior of the electrical machine concerned has been restored, and said controller (26) exits the reconfiguration mode and restores the normal operation of the vehicle, and the fault code is stored in a memory of said controller (26) until the next service visit of said vehicle (1).

10. A computer program comprising program code instructions for executing the steps of the control method according to claim 8 or 9, when said program is running on a computer.

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