Propulsion system for electric or hybrid vehicle.

Description

1 / 25 “PROPULSION SYSTEM FOR ELECTRIC OR HYBRID VEHICLE”

[0001] The present invention relates to a propulsion system for an electric or hybrid vehicle.

[0002] This propulsion system is known to comprise: - an axle connected to the vehicle's wheels, - a rotating electric machine for propelling the vehicle's wheels, and - a reduction gear located in the torque path between the rotating electric machine and the vehicle's wheels.

[0003] For reasons of energy efficiency and safety, it is important to be able to interrupt torque transmission within the aforementioned propulsion system. A known method for this purpose involves inserting a selective torque transmission interruption element in the torque path, such as a clutch or a geared clutch. The interruption of torque transmission should, as far as possible, not generate vibrations to safeguard the comfort of the vehicle user. To reduce vibrations, it is common to command the electric motor to provide zero torque, and then, once zero torque has been provided by the electric motor, to open the clutch or geared clutch. However, considering the various parameters involved during vehicle movement, such as its weight, this does not guarantee an absence of vibrations during the opening of the clutch or geared clutch.

[0004] It is therefore necessary to eliminate the disadvantage identified above.

[0005] The invention aims to satisfy this need, which is achieved, in one aspect, by a propulsion system for a hybrid or electric vehicle comprising: - an axle connected to the vehicle's wheels, - a rotating electric machine for propelling the vehicle's wheels, - a reduction gear arranged in the torque path between the rotating electric machine and the vehicle's wheels, - a selective torque transmission interruption element in Petition 870250111651, dated 04 / 12 / 2025, page 6 / 35 2 / 25 torque path, where this element has an open position and a closed position, and - a control unit configured to, upon receiving an instruction to interrupt torque transmission in the torque path while the selective torque transmission interruption element is in the closed position: - to control the rotating electrical machine so that the torque transmitted by the selective interruption element of the torque transmission remains within a predefined range of values ​​including the value 0, then - To command the transition to the open position of the selective torque transmission interrupter element.

[0006] According to the invention, this ensures that the torque transmitted by the selective torque transmission interrupter element is zero or very low before being switched to the open position. In this way, the aforementioned vibration problem is solved. The opening of the selective torque transmission interrupter element to a zero or very low transmitted torque can occur independently of the vehicle's operating mode, whether it is in the acceleration phase, deceleration phase, coasting phase, etc.

[0007] This predefined range of values ​​allows, for example, the gradient of acceleration vibrations (“jerk”) exerted on the vehicle to be between 0.1 g / s and 0.5 g / s.

[0008] In the case where the selective interruption element of the torque transmission is operationally located upstream of the reduction gear, i.e., between the rotating electrical machine and the reduction gear, this predefined range of values ​​is comprised, for example, between -2 Nm and 2 Nm.

[0009] The reduction gear mentioned may or may not constitute a gearbox, and may give rise to various ratios. In this case, the instruction to interrupt torque transmission in the torque path while the selective torque transmission interruption element is in the closed position may mean a Petition 870250111651, dated 04 / 12 / 2025, page 7 / 35 3 / 25 request for relationship change.

[0010] As will be shown in more detail later, the command of the rotating electric machine so that the torque transmitted by the selective interrupting element of the torque transmission remains within the predefined range of values ​​including the value 0 can be made based on a torque instruction signal for the torque transmitted by the selective interrupting element of the torque transmission, which is, in particular, a periodic signal passing through 0, such as a ramp or a sinusoidal signal. The application of such an instruction can cause the value of the torque transmitted by the selective interrupting element of the torque transmission to oscillate around 0.

[0011] The command unit may include: - an instruction unit, generating an instruction signal for the torque transmitted by the selective interrupt element of the torque transmission, - an observer, generating: a signal estimating the torque transmitted by the selective interruption element of the torque transmission, and a signal estimating the load torque on the shaft and - a controller configured to generate, based on the aforementioned instruction signal, from the aforementioned signal estimating the torque transmitted by the selective interruption element of the torque transmission and from the aforementioned signal estimating the load torque on the shaft, a torque instruction for the rotating electrical machine.

[0012] This control unit can estimate in real time the torque transmitted by the selective torque transmission interrupter element, and adapt the torque instruction to the electric machine so that this instruction corresponds to a torque transmitted by this selective torque transmission interrupter element that is zero or very low during the transition to the open position of the selective torque transmission interrupter element.

[0013] The transition to the open position of the selective torque transmission interrupting element occurs, for example, when the signal estimating the torque Petition 870250111651, dated 04 / 12 / 2025, page 8 / 35 4 / 25 transmitted by this selective torque transmission interruption element has a value contained within the predefined range of values ​​including the value 0, for example, the value 0.

[0014] Upon receiving a torque transmission interruption instruction on the torque path while the selective torque transmission interruption element is in the closed position, the instruction signal for the torque transmitted by the selective torque transmission interruption element, the instruction signal generated by the instruction unit, may take the form of a periodic signal passing through zero. It may be a signal with an amplitude centered at zero, for example. This instruction signal may be a sinusoidal periodic signal or a ramped periodic signal. This change in the instruction for the torque transmitted by the selective torque transmission interruption element may cause a change in the torque instruction for the rotating electrical machine.Consequently, the signal estimating the torque transmitted by this selective torque transmission interrupt element has a value in the predefined range of values ​​encompassing the value 0, specifically oscillating within this range of values ​​around the value 0. When the instruction signal for the torque transmitted by the selective torque transmission interrupt element is a ramp, a modified slope ramp can be generated when the signal estimating the torque transmitted by this selective torque transmission interrupt element has, for the first time during the command change resulting from the torque interrupt instruction, a value in the predefined range of values.

[0015] When the signal estimating the torque transmitted by this selective torque transmission interrupter has a value within the aforementioned range, a transition instruction to the open position of this selective torque transmission interrupter can be sent to the actuator of this selective torque transmission interrupter, and this instruction in the actuator can cause the transition to the desired open position, for example, at the next cancellation of the torque transmitted by this selective interrupter. The value of the signal estimating the torque transmitted by Petition 870250111651, dated 04 / 12 / 2025, page 9 / 35 5 / 25 this selective interruption element of torque transmission, therefore, is not necessarily equal to 0 during this transition to the open position.

[0016] The amplitude of this instruction signal for the torque transmitted by the selective interruption element of the torque transmission can be selected to include the different uncertainties related to the estimation of the torque transmitted by the selective interruption element of the torque transmission, uncertainties that result, in particular, from the frictions exerted on this selective interruption element of the torque transmission.

[0017] The observer can receive the following inputs: - a signal, which is a measure of the rotational speed of the electrical machine, - a signal, which is a measure of the rotational speed of the inertia modeling downstream of the selective torque transmission interruption element, and the observer can be configured to generate the following outputs: - the signal estimating the torque transmitted by the selective torque transmission interruption element, - the signal estimating the load torque on the shaft, - a signal estimating the rotational speed of the electric machine, and - a signal estimating the rotational speed of the inertia modeling downstream of the selective torque transmission interruption element.

[0018] The observer can implement a closed control loop in which: - the signal corresponding to the measurement of the rotational speed of the electric machine is compared to the signal estimating that speed and, The signal corresponding to the measured rotational speed of the inertia modeling downstream of the selective torque transmission interruption element is compared to the signal estimating that speed.

[0019] This closed circuit can be such that the above comparisons remain at zero value, so that the estimated acceleration value for the Petition 870250111651, dated 04 / 12 / 2025, page 10 / 35 6 / 25 electric machine, respectively for the inertia modeling downstream of the selective interruption element of torque transmission, is equal to the measured acceleration value for that electric machine, respectively for that inertia modeling downstream of the selective interruption element of torque transmission. This equality between estimated acceleration and measured acceleration ensures that the difference between the estimated torque and the measured torque for the electric machine is equal to the difference between the estimated torque and the measured torque for the inertia modeling downstream of the selective interruption element of torque transmission. The measurement of one torque then allows us to know the other torques and to estimate the torques that are not measured.

[0020] The inertia modeling downstream of the selective torque transmission interruption element may include all inertias such as the axle, the vehicle mass, and the inertias of the other vehicle axle. As a variation, some of these inertias are not included in the inertia modeling downstream of the selective torque transmission interruption element, for example, the vehicle mass. And this / these unincluded inertia(s) may be taken into account in the signal estimating the load torque on the axle generated by the observer.

[0021] The observer can receive as additional input a signal estimating the torque applied to the inertia modeling upstream of the selective torque transmission interruption element, between the rotating electric machine and this selective torque transmission interruption element.

[0022] The inertia modeling upstream of the selective torque transmission interruption element may include the inertia of the rotating electrical machine rotor and the inertia of any element arranged upstream of this selective torque transmission interruption element.

[0023] The observer can include at least one of the following: - a block for estimating the rotational speed of the electric machine, this block receiving as input: the signal estimating the torque applied to the inertia modeling upstream of the selective interruption element of the torque transmission, the value of Petition 870250111651, dated 04 / 12 / 2025, page 11 / 35 7 / 25 moment of inertia of the inertia modeling upstream of the selective torque transmission interruption element, the signal estimating the torque transmitted by the selective torque transmission interruption element, and a viscous friction coefficient on the inertia modeling upstream of the selective torque transmission interruption element, - a block for estimating the torque transmitted by the selective interruption element of the torque transmission, this block receiving in particular as inputs: the signal estimating the rotational speed of the rotating electrical machine and the signal estimating the rotational speed of the inertia modeling downstream of the selective interruption element of the torque transmission, - a block for estimating the velocity of the inertia modeling downstream of the selective torque transmission interruption element, this block receiving as inputs: the signal estimating the torque transmitted by the selective torque transmission interruption element, the signal estimating the load torque on the shaft, the signal estimating the rotational velocity of the inertia modeling downstream of the selective torque transmission interruption element, a viscous friction coefficient on the inertia modeling downstream of the selective torque transmission interruption element, and the value of the moment of inertia of the inertia modeling downstream of the selective torque transmission interruption element, and - a block for estimating the load torque on the shaft.

[0024] The controller can use a feedforward corrector (or correcteur d'anticipation in French) that receives as inputs: the instruction signal for the torque transmitted by the selective interruption element of the torque transmission, and the signal estimating the load torque on the shaft, this corrector providing as output a first torque instruction for the rotating electrical machine. The Petition 870250111651, dated 04 / 12 / 2025, page 12 / 35 8 / 25 The corrector can reject disturbances. When the feedforward corrector is used in combination with the two correctors mentioned below, this rejection of disturbances can simplify the calculation of the parameters of these other two correctors by rejecting the effects derived from unmeasured quantities. The use of the feedforward corrector also allows positioning the system around its theoretical equilibrium point, prejudging the system's dynamics. The other two correctors below can therefore act in regulating around this equilibrium point, thus gaining in robustness and speed.

[0025] The controller may additionally implement, or as a variation, an error corrector that receives as inputs: the instruction signal for the torque transmitted by the selective interrupt element of the torque transmission, and the signal estimating the torque transmitted by this selective interrupt element of the torque transmission, this corrector providing as output a second torque instruction for the rotating electrical machine. This error corrector ensures that this error tends to zero, thus ensuring the statistical accuracy of the regulation.

[0026] The controller may additionally implement, or as a variation, a feedback corrector that receives as input the signal estimating the torque transmitted by the selective interruption element of the torque transmission, and this corrector provides as output a third torque instruction for the rotating electrical machine. This feedback corrector, when combined with the error corrector, can complement the action of this error corrector and contribute to the stability of the regulation, thus improving the controller's reaction time.

[0027] The combined presence of the three correctors above may correspond to a preferred embodiment of the controller, in which the latter then provides an optimal response. The invention also covers the cases specified below, as well as other combinations of one or two correctors from among the three aforementioned correctors: The controller only implements the error corrector and the feedback corrector. Petition 870250111651, dated 04 / 12 / 2025, page 13 / 35 9 / 25 The controller only implements the error corrector and the feedforward corrector. The controller implements only the feedback corrector and the feedforward corrector. The controller only implements the feedforward broker.

[0028] When the three mentioned correctors are present, the torque instruction for the rotating electric machine can be generated based on the sum of the first, second, and third torque instructions.

[0029] Throughout the above description, the control unit may include a control module for an inverter / rectifier that electrically powers the rotating electric machine, and this control module generates, based on the torque instruction generated by the controller, an instruction for the inverter / rectifier to bring the torque value transmitted by the selective torque transmission interrupting element to the predefined range of values, when such cancellation is necessary.

[0030] Throughout the above description, the control unit is integrated, for example, into the vehicle transmission control unit (“TCU”) or the engine control unit (“ECU”) or another different control unit, for example a vehicle control unit, called a Vehicle Control Unit (VCU). Furthermore, the control unit can be integrated, as a variation, into the inverter / rectifier that electrically supplies the rotating electric machine. This control unit can be integrated, as a variation, into the actuator of the selective torque transmission interrupter element, which acts on the position of this selective torque transmission interrupter element. The actuator allows, in particular, the selective torque transmission interrupter element to move to the open position.

[0031] As a further variation, this command unit can be distributed among all or part of the different reception structures mentioned above for the integration of the command unit.

[0032] The control unit implements, for example, one or more digital processing devices, such as microcontrollers. The control unit is, Petition 870250111651, dated 04 / 12 / 2025, page 14 / 35 10 / 25 for example, an ASIC type integrated circuit ("Application-specific integrated circuit"). This control module provides, for example, instructions for a control unit ("driver") of the inverter / rectifier.

[0033] The selective interruption element of torque transmission is, for example, a toothed clutch. As a variation, it can be a clutch.

[0034] Throughout the above description, the selective torque transmission interruption element can be arranged upstream of the reduction gear or downstream of the reduction gear or on the reduction gear, thus selectively connecting two shafts of that reduction gear. “Upstream” and “downstream” should be understood in relation to the torque path generated by the rotating electrical machine.

[0035] The axle can be the front axle or the rear axle of the vehicle.

[0036] The electric machine may have a rated electrical power greater than or equal to 5 kW, 15 kW, 25 kW, 50 kW, 100 kW or 300 kW.

[0037] An electric machine can be a synchronous machine or an asynchronous machine. The electric machine has, for example, a nominal supply voltage of 48V, or a nominal supply voltage above 200V, in particular 300V, particularly 400V, particularly 800V.

[0038] The rotor may be made of permanent magnets. The rotor is, for example, devoid of an excitation winding. The rotor may be formed by a set of metal sheets in which the permanent magnets are arranged inside.

[0039] As a variation, the rotor may have an electrical excitation winding.

[0040] The axle is, for example, a secondary axle, the system additionally comprising a primary axle and a propulsion source for the wheels of that primary axle, and the propulsion source is another rotating electrical machine and / or a heat engine.

[0041] The invention also relates, in another aspect, to a method for controlling a propulsion system for an electric or hybrid vehicle, wherein this propulsion system comprises: - an axle connected to the vehicle's wheels, Petition 870250111651, dated 04 / 12 / 2025, page 15 / 35 11 / 25 - a rotating electric machine for propelling the vehicle's wheels, - a reduction gear arranged in the torque path between the rotating electric machine and the vehicle's wheels, and - a selective torque transmission interruption element in the torque path, wherein this element has an open position and a closed position; a method in which, upon receiving an instruction to interrupt the torque transmission in the torque path while the selective torque transmission interruption element is in the closed position: - The rotating electric machine is controlled so that the torque transmitted by the selective torque transmission interruption element remains within a predefined range of values, including the value 0, and then - The selective torque transmission interrupter element is commanded to switch to the open position.

[0042] All the foregoing explanation also applies to this other aspect of the invention.

[0043] The invention may be better understood after reading the description of non-limiting examples and analyzing the accompanying drawing in which:

[0044] [Figure 1] schematically represents a propulsion system for hybrid vehicles in which the invention can be implemented,

[0045] [Figure 2] represents a model of part of the propulsion system of Figure 1,

[0046] [Figure 3] is a block diagram of a control unit in an example implementation of the invention,

[0047] [Figure 4] is a block diagram of the controller in Figure 3

[0048] [Figure 5] is a block diagram of the observer of Figure 3, and

[0049] [Figure 6] represents curves that highlight the effect of the invention in a given example.

[0050] Figure 1 shows a propulsion system to which the invention Petition 870250111651, dated 04 / 12 / 2025, page 16 / 35 12 / 25 can be integrated. This system can belong to an electric or hybrid vehicle. In the example in question, but not limited to, the propulsion system is hybrid, as we will see below.

[0051] This system has here a primary shaft 2, which is, for example, the front shaft. This primary shaft 2 is associated here, by means of a part 11R, to a right wheel 10R and by means of a part 11L to a left wheel 10L.

[0052] This primary shaft 2 is associated here with a differential 12 and a reduction gear 13. The reduction gear 13 can form a gearbox, defining various ratios.

[0053] In the example in question, the primary shaft 2 is hybrid because it receives torque from a rotating electric machine 14, and the latter can be powered through an inverter / rectifier 15 by a battery 16 which, in the example in question, has a nominal voltage higher than 300V, for example, 400V or 800V, but which, as an option, could have a lower nominal voltage, for example, 48V. This battery 16 is monitored, for example, by a BMS type system 17 (“battery management system”). Here, an angular displacement sensor 27 is provided for the rotor of the rotating electric machine 14.

[0054] The primary shaft 2 is also hybrid in that it receives torque from a heat engine 22, as appropriate, by means of a torsional oscillation damper 21 which uses springs and / or a pendulum damping device, for example. A speed sensor 23 is associated, for example, with the heat engine 22. Speed ​​sensors 28R and 28L may also be associated with wheels 10R and 10L.

[0055] In examples not shown, primary shaft 2 is either solely electric or solely thermal.

[0056] The secondary axle 1 here is the rear axle of the vehicle, and is associated by a part 4R to a right wheel 3R and by a part 4L to a left wheel 3L. This secondary axle 1 is associated here with a differential 5 and a reduction gear 7. The reduction gear 7 receives torque from a rotating electric machine 8 powered by an inverter / rectifier 9 from the battery 16 already Petition 870250111651, dated 04 / 12 / 2025, p. 17 / 35 13 / 25 mentioned. In one variation, two different batteries may be present, one dedicated to supplying power to the rotating electric machine 8 via the inverter / rectifier 9, and the other dedicated to supplying power to the rotating electric machine 14 via the inverter / rectifier 15.

[0057] Figure 1 shows that the vehicle's onboard network has a high-voltage section 20, through which the battery 16, in the example in question, is connected to each inverter / rectifier 15, 9, and a low-voltage section 19 connected to the high-voltage section 20 by means of a DC / DC converter 18. The low-voltage section 19 here includes a battery 44 with, for example, a nominal voltage of 12V.

[0058] Similar to position sensor 27 and speed sensors 28R, 28L and 23, secondary shaft 1 is associated with an angular displacement sensor 26 for the rotor of the rotating electric machine 8 and speed sensors for the wheels 3R ​​and 3L. A speed sensor 27 is also provided at the output of the reduction gear 7 on the differential side 5.

[0059] The vehicle also includes, as is known, all or part of the different elements 42 below, such as a user interface for operating the vehicle 33, for example a button, a handbrake 34, an accelerator pedal 35 and its associated sensor 36, a steering wheel 37, a brake pedal 39 and its associated sensor 38, and a gear lever 4L

[0060] The vehicle also includes several command units 29, 30, 31 and 32, namely: - the vehicle control unit 32, also called VCU (“vehicle control unit”). This control unit manages the torque request from the driver and distributes it between the front and rear propulsion sources 8, 14 and 22. In addition, it can manage the use of available energy in the propulsion system due to recuperation operation or during battery charging 16 by the combustion engine 22. - the engine control unit 29, for controlling the heat engine 22, Petition 870250111651, dated 04 / 12 / 2025, page 18 / 35 14 / 25 - brake control unit 30, - the transmission control unit 31, specifically controlling the reduction gear 13 of the primary shaft 2.

[0061] According to the invention, a selective torque transmission interruption element 6 is present. This selective torque transmission interruption element 6 is disposed here at the output of the reduction gear 7, but the invention is not limited to this positioning. The selective torque transmission interruption element 6 may, as a variation, be disposed at the input of the reduction gear 7 or inside the reduction gear 7, thus selectively connecting two shafts of this reduction gear 7.

[0062] This selective torque transmission interruption element 6 has an open position in which it interrupts torque transmission towards wheels 3R ​​and 3L, and a closed position in which this torque transmission towards wheels 3R ​​and 3L is effective. The change in position of this selective torque transmission interruption element 6 is caused in at least one direction by an actuator. The selective torque transmission interruption element 6 is, for example, bistable, normally open monostable, or normally closed monostable. The change from the closed position to the open position is made, for example, by the actuator.

[0063] The selective torque transmission interruption element 6 is, for example, a clutch or a toothed clutch. Preferably, it is a selective torque transmission interruption element that uses an obstacle transmission, for example, a groove or a tooth, such as a toothed clutch.

[0064] The invention ensures that the selective torque transmission interruption element 6 moves to the open position while the torque it transmits is zero or very low.

[0065] For this purpose, the invention uses a control unit, described below.

[0066] The propulsion system described with reference to Figure 1 may be Petition 870250111651, dated 04 / 12 / 2025, page 19 / 35 15 / 25 modeled as shown in Figure 2.

[0067] Figure 2 shows that the selective interruption element of torque transmission 6 can be modeled as a connection 53 between an inertia 46 modeling upstream of this connection 53 and an inertia 48 modeling downstream of this connection 53.

[0068] The inertia 46 modeling upstream of connection 53 includes, for example, the inertia of the rotor of the rotating electrical machine 8 and the inertia of any element arranged upstream of that connection 53.

[0069] The inertia 48 modeling downstream of connection 53 the selective interruption element of torque transmission can encompass all inertias, such as the secondary shaft 1, optionally the vehicle mass, and the inertias of the vehicle's primary shaft 2.

[0070] According to the model in Figure 2, the torque transmitted by connection 53 can be approximated by the equation below. [Math. 1 ] =-----------MomentaÍtg4li-------xCouple^ + iHomentJneríie4S+ M a menti nei'tie^ Momenttnertie.í , ---------------—------x Couple^ Mt>menthteri:íe4e+M / >mentinerrie4ir CAPTION: Math = Mathematical Formula Couple = Torque Moment of inertia

[0071] Where Torque45 corresponds to the estimate of the torque applied by the rotating electric machine 8 to the inertia 46 modeling upstream of the selective interruption element of the torque transmission and Torque49 corresponds to the estimate of the torque on the secondary shaft 1.

[0072] This model in Figure 2 is used, in the example in question, by observer 54, which will be described later. When the positioning of the selective torque transmission interruption element 6 is one of those mentioned previously, which differs from that of connection 53 in Figure 2, the moment of inertia values ​​of inertias 46 and 48, as well as the reductions applied to Petition 870250111651, dated 04 / 12 / 2025, page 20 / 35 16 / 25 speeds, can be adapted with calibration by observer 54 to take into account the actual architecture of the propulsion system.

[0073] The control unit is as shown in Figure 3, for example.

[0074] This control unit includes an instruction unit 55, which generates an instruction signal 61 for the torque transmitted by the selective interrupt element of the torque transmission 6.

[0075] This command unit also includes an observer 54, which will be described by referring to Figure 5. Observer 54 generates, in the example in question: - a signal 60 estimating the torque transmitted by the selective interruption element of the torque transmission 6, and - signal 49 estimating the load torque on shaft 1, which provides the aforementioned Torque49 value.

[0076] The control unit also includes a controller 56, which will be described by referring to Figure 4. This controller 56 is configured in the example in question to generate, based on the instruction signal 61, the signal 60 estimating the torque transmitted by the selective interruption element of the torque transmission 6 and the signal 49 estimating the load torque on shaft 1, a torque instruction 59 for the rotating electric machine 8.

[0077] Instruction unit 55 uses, for example, the following inputs: - a signal 62 defining an initial instruction for the torque transmitted by the selective interrupt element of the torque transmission 6, namely, the torque instruction value when the opening of the selective interrupt element of the torque transmission 6 is received, for example, during a gear change request, and - a signal 63 defining a final instruction for the torque transmitted by the selective interrupt element of the torque transmission 6, namely, the final value to be reached for this opening of the selective interrupt element of the torque transmission 6, which in the example described is 0, Petition 870250111651, dated 04 / 12 / 2025, page 21 / 35 17 / 25 - a signal 64 corresponding to the measured rotational speed of the rotating electrical machine 8, originating, for example, from sensor 26, - a signal 65 corresponding to the rotational speed at the output of reduction gear 7 measured by sensor 25.

[0078] The instruction signal 61 generated by instruction unit 55 is considered, in the example in question, a periodic ramp-shaped signal, centered at 0. If appropriate, instruction unit 55 can generate a torque instruction in advance for the rotating electrical machine, and this advance torque instruction is taken into account by the controller 56 when generating the torque instruction for the rotating electrical machine 59.

[0079] As can be seen in Figure 5, observer 54 receives as inputs, for example, the signal 64 already mentioned, and the signal 65 already mentioned. This observer 54 provides as outputs the signals 49 and 60 already mentioned, and these are, respectively, the signal estimating the torque transmitted by the selective interruption element of the torque transmission 6 and the signal estimating the load torque on the secondary shaft 1.

[0080] Figure 5 shows that, for observer 54, other additional outputs are possible, namely: - a signal 47 estimating the rotational speed of the rotating electrical machine 8, and - a signal 50 estimating the speed of inertia 48.

[0081] Figure 5 also shows that observer 54 can implement a closed loop in which an error vector is generated in 93 by comparing: - signal 64 corresponding to the measurement of the rotational speed of the rotating electrical machine 8 to signal 47 estimating that speed and, - Signal 65 corresponds to the measurement of the rotational speed at the output of reduction gear 7, while signal 50 estimates that speed.

[0082] This closed loop seeks to keep the result of each comparison at zero.

[0083] This closed circuit uses a corrector 87 characterized by a set Petition 870250111651, dated 04 / 12 / 2025, page 22 / 35 18 / 25 of parameters 98. At the output of this corrector 87 several correction signals 94 to 97 are found, namely: - a correction signal 94 on the estimate of the rotational speed of the electric machine 8, - a correction signal 95 on the estimate of the torque transmitted by the selective interruption element of the torque transmission 6, - a correction signal 96 on the estimate of the rotational speed at the output of reduction gear 7, and - a correction signal 97 on the load torque estimate on secondary shaft 1.

[0084] The parameter set 98 is presented, for example, in matrix form, and the correction signals 94 to 97 are obtained, for example, by multiplying the error vector in 93 by this matrix. These correction signals are received at the input of several blocks 88 to 91 which will now be described. The values ​​of the parameter set 98 are chosen, for example, to ensure the convergence of the estimates provided by observer 54 quickly, for example, in a time between 50 ms and 300 ms.

[0085] Block 88 is an estimation block that generates signal 47, which is an estimate of the rotational speed of electric machine 8. Block 88 receives the following inputs: - signal 45 estimating the torque applied to the inertia 46 modeling the upstream of the selective torque transmission interruption element 6 according to the model in Figure 2, - the symbol 46 is the value of the moment of inertia of that inertia 46, always according to the model in Figure 2, - signal 60 estimating the torque transmitted by the selective interruption element of the torque transmission 6, and - a sign 51, which is a coefficient of viscous friction over inertia 46.

[0086] As shown in Figure 5, this block 88 can also receive as input the value of signal 47 estimated by block 88 during the iteration of Petition 870250111651, dated 04 / 12 / 2025, page 23 / 35 19 / 25 previous calculation.

[0087] Within this block 88, the difference between signals 45 and 60, to which a frictional torque determined using signals 47 and 51 is added, is then multiplied by the value of the moment of inertia according to 46, and then modified taking into account the correction signal 94. The result is integrated with respect to time to obtain an estimate of the rotational speed of the electric machine 8 according to signal 47.

[0088] Block 89 is an estimation block that generates signal 60, which is an estimate of the torque transmitted by the selective interruption element of the torque transmission 6. This block 89 receives as inputs: signal 47 estimating the rotational speed of the electric machine 8, signal 50 estimating the speed of the inertia 48 modeling downstream of the selective interruption element of the torque transmission 6, and the model parameters 53 used for the selective interruption element of the torque transmission 6, such as the stiffness of this connection and / or an internal damping torque. Within this block 89, the difference between signals 47 and 50, to which the correction signal 95 is added, is integrated with respect to time to estimate the voltage applied to the selective interruption element of the torque transmission 6.To estimate the torque transmitted by this selective torque transmission interruption element 6, this voltage is multiplied by the stiffness of model 53 used for the selective torque transmission interruption element 6 according to Figure 2. In a variation, signal 60 can also be obtained by an internal damping torque obtained based on the difference between signals 47 and 50, this difference being multiplied by a damping factor of model 53.

[0089] Block 90 is an estimation block that generates signal 50, which is an estimate of the inertia velocity 48 modeling downstream of the selective torque transmission interruption element 6. This block 90 receives the following inputs: - signal 60 estimating the torque transmitted by the selective interruption element of the torque transmission 6, Petition 870250111651, dated 04 / 12 / 2025, page 24 / 35 20 / 25 - signal 49 estimating the load torque on secondary shaft 1, - the value assigned to the signal 50 by block 90 during the previous calculation iteration, - signal 52, which is a viscous friction coefficient over inertia 48 modeling downstream of the selective torque transmission interruption element 6, and - the symbol 48, which is the value of the moment of inertia of that inertia 48, always according to the model in Figure 2.

[0090] Within this block 90, the difference between signals 60 and 49, to which the friction torque obtained using signals 50 and 52 is added, is divided by the moment of inertia value according to signal 48 and then corrected taking into account the correction signal 96. The result is integrated with respect to time to obtain signal 50.

[0091] Block 91 is an estimation block that generates signal 49, which is an estimate of the load torque on secondary shaft 1. This block 91 receives correction signal 97 as input. This block is based, for example, on the fact that the nth-order time derivative of signal 49 must be zero.

[0092] Block 92 is a selector that allows signals 47 and 50 to be sent towards comparator 86.

[0093] Controller 56 from Figure 3 will now be described, with reference to Figure 4. In this Figure 3 it can be observed that controller 56 uses, for example, three distinct correctors 73, 74 and 75, which will be described below.

[0094] A first controller 73 uses a feedforward broker that receives the following inputs: - the instruction signal 61 for the torque transmitted by the selective interruption element of the torque transmission 6, and - signal 49 estimating the load torque on secondary shaft 1.

[0095] This broker uses, for example, a set of parameters 77 which are, for example, two gains K1 and K2, where each of these gains is multiplied, respectively, for example with one of the input signals 61, 49. Petition 870250111651, dated 04 / 12 / 2025, page 25 / 35 21 / 25

[0096] However, the invention is not limited to gains of constant value. The gain values ​​can vary by non-linear formulas or data storage tables, the chosen value depending on the rotational speed of the electric machine 8 and / or the rotational speed of the reduction gear output, and / or the temperature of that electric machine 8 or the reduction gear 7, for example, and / or the reduction ratio applied by the reduction gear 7, if the latter allows different ratios. As a variation, the corrector is not a proportional corrector, it is of the proportional-derivative type, for example.

[0097] The first controller 73 provides as output a signal 70, which is a first torque instruction for the rotating electrical machine.

[0098] The second controller 74 can implement an error corrector that receives the following inputs: - the instruction signal 61 for the torque transmitted by the selective interruption element of the torque transmission 6, and - signal 60 estimating the torque transmitted by the selective interruption element of torque transmission 6.

[0099] These two inputs are compared in 80 and this difference is used by the corrector to generate as output a signal 71, which is a second torque instruction for the rotating electric machine. The corrector 74 can use at least one integration. In addition, it can implement an anti-derivative system of the integrator based on the limit values ​​for the torque of the electric machine 8. This anti-derivative system allows the integration performed by the corrector to be suspended when these torque limit values ​​are reached. The corrector uses a set of parameters 78 which are, for example, the gains. As mentioned in relation to the controller 73, these gains are not necessarily of constant value.The gain values ​​may vary due to non-linear formulas or data storage tables, and the chosen value may depend on the rotational speed of the electric machine 8 and / or the rotational speed of the reduction gear output, and / or the temperature of that electric machine 8 or of the... Petition 870250111651, dated 04 / 12 / 2025, page 26 / 35 22 / 25 reduction gear 7 and / or the reduction ratio applied by reduction gear 7, if the latter allows different ratios, for example.

[0100] The third controller 75 can implement a feedback corrector (“feedback controller”). This controller receives as input the signal 60 estimating the torque transmitted by the selective interruption element of the torque transmission 6. This corrector provides as output a signal 72, which is a third torque instruction 72 for the rotating electrical machine. This third torque instruction allows stabilizing the closed-loop system including the rotating electrical machine 8, the reduction gear 7 and the observer 54, similar to a sensor. The corrector uses a set of parameters 79 which are, for example, the gains. As mentioned in relation to controller 73 and controller 74, these gains are not necessarily of constant value.The gain values ​​can vary due to non-linear formulas or data storage tables, with the chosen value depending on the rotational speed of the electric machine 8 and / or the rotational speed of the reduction gear output, and / or the temperature of that electric machine 8 or the reduction gear 7 or the oil in the reduction gear, for example, and / or the reduction ratio applied by the reduction gear 7, if the latter allows different ratios, for example. In one variation, this corrector is not a proportional corrector, but may be of the proportional-derivative type.

[0101] When the three aforementioned correctors 73, 74 and 75 are present, the signal 59 corresponding to the torque instruction for the rotating electric machine can be generated based on the sum of the first, second and third torque instructions by an adder 81. The signal at the output of this adder 81 can optionally drive a limiting block 85. The latter limits the values ​​of the torque instruction signal 59 for the electric machine 8 to a range defined by the extremes 82 and 83, and these extremes can be dynamically defined as a function of the speed of the electric machine 8. The signal at the output of this limiting block 85 can then be received by a control module 57 of the electric machine 8, and this control module generates a command signal 58 for the inverter / rectifier 9 through which the Petition 870250111651, dated 04 / 12 / 2025, page 27 / 35 23 / 25 electric machine 8 is powered by battery 16.

[0102] The described control unit allows, upon receiving an instruction to interrupt torque transmission in the torque path while the selective torque transmission interrupt element 6 is in the closed position: - to control the rotating electric machine 8 in such a way as to cancel or strongly reduce the torque transmitted by the selective interruption element of the torque transmission 6, and then - command the selective torque transmission interruption element 6 to switch to the open position.

[0103] Figure 6 represents the following as a function of time: - at the top, the evolution of signals 47 and 50, which represent, respectively, the estimated speed of the rotating electrical machine 8 and the estimated speed of the inertia 48, - in the middle section, the evolution of signals 59, 60 and 61, which represent, respectively, the torque instruction for the rotating electric machine, the estimate of the torque transmitted by the selective interruption element of the torque transmission 6, and instruction 61 for the torque transmitted by the selective interruption element of the torque transmission 6, - at the bottom, the evolution of the state of the selective torque transmission interrupting element 6, the “open / closed” command for that state of the selective torque transmission interrupting element 6 according to a signal 130, and the “open / close” command for the actuator of the selective torque transmission interrupting element 6 according to a signal 140.

[0104] Note that between instants t0 and t1, the selective torque transmission interrupting element 6 is in the closed position and a reduction gear ratio 7 is engaged. As shown in Figure 6, in this configuration there may be a difference between the estimate of the torque transmitted by the selective torque transmission interrupting element 6 according to the signal. Petition 870250111651, dated 04 / 12 / 2025, page 28 / 35 24 / 25 and the torque instruction for the rotating electric machine 8 according to signal 59.

[0105] At an instant t1, an instruction to interrupt the torque transmission in the torque path is received. From this instant t1, instruction 61 for the torque transmitted by the selective torque transmission interrupt element 6 is modified so as to oscillate around the value 0. This instruction 61 modifies the values ​​so that it remains within a predefined range of values, defined between an upper value, which here is a constant according to level 110, and a lower value, which here is a constant according to level 120. However, the invention is not limited to constant values ​​for the upper and lower values.

[0106] The values ​​according to levels 110 and 120 are chosen, for example, so that the acceleration vibration gradient (“jerk”) exerted on the vehicle is between 0.1 g / s and 0.5 g / s. When the selective torque transmission interruption element 6 is operationally arranged between the rotating electric machine and the reduction gear, this predefined range of values ​​is, for example, between -2 Nm and 2 Nm. In other cases, the values ​​for levels 110 and 120 are adapted taking into account the reduction ratio(s) in the reduction gear 7.

[0107] This instruction modification is accompanied by a change in the torque instruction for the rotating electric machine 8 according to signal 59 so that signal 60, namely, respectively, the estimate of the torque transmitted by the selective interruption element of the torque transmission 6, accompanies signal 61, which is the instruction for that torque transmitted by the selective interruption element of the torque transmission 6.

[0108] Figure 6 highlights that when the signal 60 estimating the torque transmitted by the selective torque transmission interrupter element 6 reaches the predefined range of values, the actuator can receive an instruction that allows the selective torque transmission interrupter element 6 to transition to the open position. If appropriate, simultaneously or virtually simultaneously, upon receiving the Petition 870250111651, dated 04 / 12 / 2025, page 29 / 35 25 / 25 instruction by the actuator, a different slope ramp can be generated for instruction 61 for the torque transmitted by the selective interruption element of the torque transmission 6.

[0109] At time t2, the selective interrupt element of the torque transmission 6 switches to the open position, and no gear is engaged. This time t2 occurs while the instruction signal 61 for the torque transmitted by the selective interrupt element of the torque transmission 6 is in the oscillation phase mentioned above and while the torque estimation signal 60 transmitted by the selective interrupt element of the torque transmission 6 has a value within the predefined range of values.

[0110] Once the selective torque transmission interrupter 6 has been switched to the open position, the oscillation of the instruction signal 61 around 0 is interrupted, and the rotating electrical machine 8 is no longer controlled by the control unit. Petition 870250111651, dated 04 / 12 / 2025, p. 30 / 35

Claims

1 / 5 CLAIMS 1. Propulsion system for a hybrid or electric vehicle comprising: - a shaft (1) connected to the wheels (3R, 3L) of the vehicle, - a rotating electric machine (8) for propelling the wheels of the vehicle, - a reduction gear (7) disposed in the torque path between the rotating electric machine (8) and the wheels (3R, 3L) of the vehicle, - a selective torque transmission interruption element (6) in the torque path, this element having an open position and a closed position, and - a control unit configured to, upon receiving an instruction to interrupt torque transmission in the torque path while the selective torque transmission interruption element (6) is in the closed position: - command the rotating electric machine (8) so that the torque transmitted by the selective torque transmission interruption element (6) is within a predefined range of values ​​including the value 0,then - command the passage to the open position of the selective torque transmission interrupting element (6). characterized by the fact that the command of the rotating electric machine so that the torque transmitted by the selective torque transmission interrupting element (6) is within the predefined range of values ​​encompassing the value 0 is carried out based on an instruction signal (61) for the torque transmitted by the selective torque transmission interrupting element (6), which is a periodic signal passing through 0, in particular a ramp or a sinusoidal signal.

2. System, according to the preceding claim, characterized in that the control unit comprises: - an instruction unit (55), which generates the instruction signal (61) for the torque transmitted by the selective interruption element of the torque transmission (6), - an observer (54), which generates a signal (60) estimating the torque transmitted by the selective interruption element of the torque transmission (6), and a signal (49) estimating the load torque on the shaft (1), and - a controller (56) configured to generate, based on said instruction signal (61), said signal (60) estimating the torque transmitted by the selective interruption element of the torque transmission (6) and said signal (49) estimating the load torque on the shaft, a torque instruction (59) for the rotating electric machine.

3. System, according to claim 1 or 2, characterized in that, upon receiving an instruction to interrupt torque transmission in the torque path while the selective torque transmission interrupt element (6) is in the closed position, the instruction signal (61) for the torque transmitted by the selective torque transmission interrupt element (6) takes the form of a periodic signal that passes through zero.

4. System according to claim 3, characterized in that the instruction signal (61) takes the form of a sinusoidal or ramp periodic signal.

5. System, according to claim 3, characterized in that the observer (54) receives as inputs: - a signal (64) that is a measure of the rotational speed of the electric machine (8), - a signal (65) that is a measure of the rotational speed of the inertia (48) modeling downstream of the selective interruption element of the torque transmission (6), and the observer is configured to generate as outputs: - the signal (60) estimating the torque transmitted by the selective interruption element of the torque transmission, - the signal (49) estimating the load torque on the shaft, - a signal (47) estimating the rotational speed of the electric machine, and - a signal (50) estimating the rotational speed of the inertia (48) modeling downstream of the selective interruption element of the torque transmission.

6. System, according to claim 5, characterized in that the observer (54) implements a closed control circuit in which: - the signal (64) which is a measure of the rotational speed of the electric machine is compared with the signal (47) estimating that speed and, - the signal (65) which is a measure of the speed of the inertia (48) modeling downstream of the selective interruption element of the torque transmission (6) is compared with the signal (50) estimating that speed.

7. System according to claim 6, characterized in that the observer (54) comprises at least one: - a block (88) for estimating the rotational speed of the electric machine, this block receiving, mainly, as input: the signal estimating the torque applied to the inertia (46) modeling upstream of the selective interruption element of the torque transmission (6), the value of the moment of inertia of the inertia (46) modeling upstream of the selective interruption element of the torque transmission, the signal estimating the torque transmitted by the selective interruption element of the torque transmission, and a viscous friction coefficient of the inertia modeling upstream of the selective interruption element of the torque transmission, - a block (89) for estimating the torque transmitted by the selective interruption element of the torque transmission (6),wherein this block receives mainly as inputs: the signal (47) estimating the rotation speed of the electric machine and the signal (50) estimating the rotation speed of the inertia (48) modeling downstream of the selective interruption element of the torque transmission, - a block (90) to estimate the speed of the inertia (48) modeling downstream of the selective interruption element of the torque transmission (6), wherein this block (90) receives mainly as inputs: the signal (60) estimating the torque transmitted by the selective interruption element of the torque transmission (6), the signal (49) estimating the load torque on the shaft, the signal (50) estimating the rotation speed of the inertia (48) modeling downstream of the element of Petition 870250090842, of 06 / 10 / 2025, page. 14 / 17 4 / 5 selective interruption of torque transmission (6), a viscous friction coefficient in the inertia modeling downstream of the selective interruption element of torque transmission,and the value of the moment of inertia of the inertia modeling downstream of the selective interruption element of the torque transmission, and - a block (91) to estimate the load torque on the shaft (1)., 8. System, according to any one of claims 2 to 7, characterized in that the controller (56) implements a feedforward corrector (73) receiving as inputs: the instruction signal (61) for the torque transmitted by the selective interrupt element of the torque transmission, and the signal (49) estimating the load torque on the shaft (1), this corrector providing at the output a first torque instruction (70) for the rotating electric machine (8).

9. System, according to any one of claims 2 to 8, characterized in that the controller (56) implements an error corrector receiving as inputs: the instruction signal (61) for the torque transmitted by the selective interrupt element of the torque transmission (6), and the signal (60) estimating the torque transmitted by this selective interrupt element of the torque transmission, this corrector providing at the output a second torque instruction (71) for the rotating electric machine (8).

10. System, according to any one of claims 2 to 9, characterized in that the controller (56) implements a feedback corrector receiving as input the signal (60) estimating the torque transmitted by the selective interruption element of the torque transmission (6), and this corrector provides at the output a third torque instruction (72) for the rotating electric machine (8).

11. System, according to claims 8, 9 and 10, characterized in that the torque instruction (59) for the rotating electric machine is generated based on the sum of the first (70), second (71) and third (72) torque instructions.

12. System, according to any one of claims 2 to 11, characterized in that the control unit comprises a control module (57) of an inverter / rectifier (9) that electrically feeds the rotating electric machine (8), wherein this control module (57) generates, based on the torque instruction (59) generated by the controller (56), an instruction (58) for the inverter / rectifier (9) to bring the torque value transmitted by the selective torque transmission interruption element (6) to the predefined range of values.

13. System, according to any of the preceding claims, characterized in that the selective interruption element of the torque transmission (6) is a toothed clutch.

14. System, according to any of the preceding claims, characterized in that the selective interruption element of the torque transmission (6) is disposed upstream of the reduction gear (7), or downstream of the reduction gear (7), or in the reduction gear (7), thus selectively connecting the two shafts of this reduction gear.

15. System, according to any of the preceding claims, characterized in that the axle (1) is the front axle or the rear axle of the vehicle.

16. Propulsion system, according to any of the preceding claims, characterized in that said shaft (1) is a secondary shaft, the system further comprising a primary shaft (2) and a propulsion source (14, 22) for the wheels (10R, 10L) of this primary shaft (2), and this propulsion source is another rotating electric machine or a heat engine. Petition 870250090842, dated 06 / 10 / 2025, pp. 16 / 17

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