Controlling coupling during charging phases of a battery of a vehicle with a hybrid drivetrain

Abstract

The invention relates to a control method implemented in a vehicle comprising a heat engine supplying a first torque and coupled to a gearbox by a coupling device including a hydraulic circuit and delivering a second torque from the first torque in a coupling position, and an electric motor installed between the coupling device and the gearbox and suitable for charging a battery in the presence of the second torque. This method comprises a step (10-30) wherein, in the event of a transition between the parking and driving positions of the gearbox during a charging phase, the coupling position is prohibited during a chosen time, and then once this time has elapsed, a new placement in the coupling position is authorised.

Description

DESCRIPTION TITLE: COUPLING CONTROL DURING CHARGING PHASES OF A BATTERY OF A HYBRID GMP VEHICLE The present invention claims priority from French application No. 2301203 filed on 09.02.2023, the content of which (text, drawings and claims) is incorporated herein by reference. Technical field of the invention

[0001] The invention relates to vehicles comprising a hybrid powertrain (or GMP) and allowing the recharging of a battery, and more precisely the control of the recharging of such a battery. State of the art

[0002] Certain vehicles, possibly of the automobile type, include a hybrid powertrain (or GMP), i.e. comprising at least one thermal motor and at least one electric motor, and a battery which can be recharged at least by the latter when it receives torque produced by the thermal motor.

[0003] In some powertrains, the thermal prime mover is suitable for being coupled to a gearbox via a hydraulic circuit coupling device (such as a clutch), and the electric prime mover is installed between this coupling device and this gearbox and associated with the rechargeable battery.

[0004] When the coupling device is in its coupling position and the thermal motor provides it with a first torque, it delivers a second torque from this first torque.

[0005] When the vehicle is in a recharging phase, the electric motor is capable of recharging the associated battery by presence of the second torque. More precisely, the electric motor produces from the second torque a third torque which has a negative value opposite to that of the first torque, to recharge the associated battery.

[0006] As is known to those skilled in the art, in the presence of certain hydraulic architectures, such as for example when the gearbox is of the so-called "dual clutch (or DCT)" type, during a recharging phase each time a transition occurs between the parking position and a so-called "active" position (neutral or forward or reverse position) of the gearbox, the pressure suddenly drops in the hydraulic circuit of the coupling device, and therefore the second torque delivered by the latter also suddenly collapses since it is temporarily placed in its decoupled position. This results in a very rapid cancellation of the first and third torques which causes a shock accompanied by a surge in the speed of the thermal engine and a collapse in the speed (or a sub-speed) of the electric engine which are clearly heard in the passenger compartment of the vehicle.Furthermore, there is again a shock when the pressure suddenly returns to normal in the hydraulic circuit of the coupling device, and therefore when the latter is again placed in its coupling position, because it is difficult to control the speed of the thermal engine when the second torque transmitted by the coupling device is not precisely known. Such shocks and speed noises can be worrying for the passengers of the vehicle because they do not understand the cause, and therefore they degrade the driving pleasure and the quality image of the vehicle.

[0007] The invention therefore aims in particular to improve the situation. Presentation of the invention

[0008] For this purpose, it proposes in particular a control method intended to be implemented in a vehicle comprising a powertrain comprising, on the one hand, a thermal motor machine suitable for providing a first torque and for being coupled to a gearbox, offering a parking position and at least one active position, by a coupling device comprising a hydraulic circuit and suitable, in a coupling position, for delivering a second torque from the first torque, and, on the other hand, an electric motor installed between the coupling device and gearbox and suitable in a recharging phase for recharging an associated battery in the presence of the second torque.

[0009] This control method is characterized by the fact that it includes a step in which, in the event of a transition between the parking and activity positions during a recharging phase, the coupling position is prohibited for a chosen duration, then at the end of the latter, a new placement in the coupling position is re-authorized.

[0010] Thanks to the invention, the sudden drop in pressure in the hydraulic circuit no longer has any consequences, which improves driving pleasure and prevents a constraint imposed by the hydraulic architecture of the powertrain from degrading the quality image of the vehicle.

[0011] The control method according to the invention may include other characteristics which may be taken separately or in combination, and in particular:

[0012] - in its step, one can prohibit the coupling position immediately after being informed of the transition;

[0013] - in a first embodiment, in its step, the chosen duration can be determined based on an estimate of a current temperature of an oil circulating in the hydraulic circuit;

[0014] - in this first embodiment, in its step, the duration can be determined based on data stored in at least one table establishing a correspondence between oil temperatures and durations;

[0015] - in a second embodiment, in its step, a predefined duration can be used.

[0016] The invention also provides a computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing a control method of the type presented above, in a vehicle comprising a powertrain comprising, on the one hand, a thermal motor capable of providing a first torque and of being coupled to a gearbox, offering a parking position and at least one active position, by a coupling device comprising a hydraulic circuit and capable, in a coupling position, of delivering a second torque from the first torque, and, on the other hand, an electric motor installed between the coupling device and gearbox and capable in a recharging phase of recharging an associated battery in the presence of the second torque, to control battery recharging phases in the event of a transition between the parking and active positions.

[0017] The invention also proposes a control device intended to equip a vehicle comprising a powertrain comprising, on the one hand, a thermal motor machine capable of providing a first torque and of being coupled to a gearbox, offering a parking position and at least one active position, by a coupling device comprising a hydraulic circuit and capable, in a coupling position, of delivering a second torque from the first torque, and, on the other hand, an electric motor machine installed between the coupling device and gearbox and capable in a recharging phase of recharging an associated battery in the presence of the second torque.

[0018] This control device is characterized by the fact that it comprises at least one processor and at least one memory arranged to carry out the operations consisting, in the event of a transition between the parking and activity positions during a recharging phase, of prohibiting the coupling position for a chosen duration, then of the expiration of the latter to re-authorize a new placement in the coupling position.

[0019] The invention also proposes a vehicle, possibly of the automobile type, and comprising, on the one hand, a powertrain comprising a thermal motor capable of providing a first torque and of being coupled to a gearbox, offering a parking position and at least one active position, by a coupling device comprising a hydraulic circuit and capable, in a coupling position, of delivering a second torque from the first torque, and an electric motor installed between the coupling device and gearbox and capable in a recharging phase of recharging an associated battery in the presence of the second torque, and, on the other hand, a control device of the type presented above. Brief description of the figures

[0020] Other characteristics and advantages of the invention will appear on examining the detailed description below, and the appended drawings, in which:

[0021] [Fig. 1] schematically and functionally illustrates an exemplary embodiment of a vehicle comprising a control device according to the invention and a hybrid GMP transmission chain and associated with a supervision computer,

[0022] [Fig. 2] schematically and functionally illustrates an exemplary embodiment of a supervision computer comprising an exemplary embodiment of a control device according to the invention, and

[0023] [Fig. 3] schematically illustrates an example of an algorithm implementing a control method according to the invention. Detailed description of the invention

[0024] The invention aims in particular to propose a control method, and an associated DC3 control device, intended to enable control of the recharging phases of a BA battery, of a vehicle V including a hybrid powertrain (or GMP), in the event of the BV gearbox transitioning between its parking position and an active position.

[0025] In the following, it is considered, by way of non-limiting example, that the vehicle V is of the automobile type. It is for example a car, as illustrated in figure 1. But the invention is not limited to this type of vehicle. It indeed concerns any type of vehicle comprising a hybrid GMP transmission chain (thermal and electric). Thus, it concerns land vehicles (utility vehicles, camper vans, minibuses, coaches, trucks, motorcycles, road machinery, construction machinery, agricultural machinery, leisure machinery (snowmobile, kart), tracked machinery, trains and trams, for example), aircraft and boats.

[0026] Figure 1 schematically shows a vehicle V comprising a hybrid GMP transmission chain (and therefore in particular a thermal motor MMT and an electric motor MME), a supervision computer CS, a rechargeable battery BA, and a control device DC3 according to the invention.

[0027] As illustrated, the transmission chain also comprises, here, a motor shaft AM, a first coupling device DC1, a second coupling device DC2, a gearbox BV, and a transmission shaft AT.

[0028] The operation of the transmission chain (and therefore of the GMP) is supervised by a CS supervision computer.

[0029] The thermal motor MMT comprises a crankshaft (not shown) which is fixedly secured to the motor shaft AM in order to drive the latter (AM) in rotation. This thermal motor MMT is capable of operating according to a first speed to provide a first torque c1, on command from the supervision computer CS. In addition, it (MMT) is capable of being coupled to a gearbox BV, having a second speed as input, via at least the first coupling device DC1. The latter (DC1) is capable of delivering a second torque c2 from the first torque c1, in particular for at least one train T1 of driving wheels, when it is in its coupled position and therefore when it couples the thermal driving machine MMT to the gearbox BV.

[0030] It should be noted that the operation of the MMT thermal motor is controlled either by a speed setpoint when the first coupling device DC1 is sliding, or by a torque setpoint when the first coupling device DC1 is in its coupling position (or closed), the speed or torque setpoint being determined by the CS supervision computer.

[0031] The second torque c2 is defined by a clutch torque setpoint cce which is determined by the supervision computer CS. It will be noted that this clutch torque setpoint cce is transmitted by the supervision computer CS to a computer CE associated with the first coupling device DC1, controlling the operation of the latter (DC1) and responsible for converting this clutch torque setpoint cce into a hydraulic pressure setpoint cph for the hydraulic circuit of the first coupling device DC1.

[0032] For example, the first coupling device DC1 may be a hydraulic circuit clutch. But it could be of another type as long as it includes a hydraulic circuit to move it from its decoupling position to its coupling position (and vice versa).

[0033] Also for example, the train T1 can be located in the front part PW of the vehicle V. It is preferably, and as illustrated, coupled to the transmission shaft AT via a differential (here front) DV. But in a variant this train T 1 could be the one referenced T2 which is located in the rear part PRV of the vehicle V.

[0034] The electric motor MME is installed between the first coupling device DC1 and the gearbox BV, and is capable of providing a third torque c3, on the order of the supervision computer CS. Its operation is controlled by a machine computer CM.

[0035] When the first coupling device DC1 has been placed in its coupled (or fully closed) state and the thermal motor MMT is operating (and therefore at a first non-zero speed to provide the first torque c1), the first coupling device DC1 delivers a second torque c2 which is added to a possible third torque c3 provided, upstream of the gearbox BV, by the electric motor MME when it is supplied with electrical energy by a rechargeable battery BA. When the first coupling device DC1 has been placed in its uncoupled (or fully open) state, only the electric motor MME can provide a third torque c3 upstream of the gearbox BV.

[0036] The electric motor MME is also arranged, in a recharging phase, so as to recharge the associated battery BA in the presence of the second torque c2. More precisely, it (MME) is capable in a recharging phase of producing from the second torque c2 (from the first coupling device DC1) a third torque c3 which has a negative value opposite to that of the first torque c1 (supplied by the thermal motor MMT) to recharge the associated battery BA.

[0037] For example, the BA battery can be of the cellular type. In this case, it includes electrical energy storage cells, possibly electrochemical (such as lithium-ion (or Li-ion) or Ni-Mh or Ni-Cd cells). Also, for example, this BA battery can be of the 450 V type. But this is not an obligation. Indeed, it could alternatively be of the 48 V or 600 V type, for example.

[0038] The BV gearbox is automated, and includes in particular (and conventionally) a parking position and at least one so-called "activity" position (neutral or forward or reverse position). As a non-limiting example, the BV gearbox may be of the so-called "dual clutch (or DCT)" type. But the invention is not limited to this type of gearbox (the important thing being that it includes in particular a parking position and at least one activity position).

[0039] It will be noted that in the example illustrated non-limitingly in Figure 1 the first coupling device DC1, the electric motor MME and the gearbox BV are part of a gearbox assembly EBV. But this is not an obligation.

[0040] It will also be noted that in the example illustrated non-limitingly in Figure 1, the transmission chain also includes a second coupling device DC2 installed downstream of the first coupling device DC1 and electric motor MME and upstream of the gearbox BV. But this is not an obligation. Furthermore, the second coupling device DC2 is here part of the gearbox assembly EBV. But this is not an obligation.

[0041] As mentioned above, the invention proposes in particular a control method intended to enable the control of the recharging phases of the BA battery in the event of a transition of the BV gearbox between its parking position and one of its active positions (in either direction), for example due to the driver's action on the gear lever.

[0042] This (control) method can be implemented at least partially by the control device DC3 (illustrated at least partially in Figures 1 and 2) which comprises for this purpose at least one processor PR1, for example a digital signal processor (or DSP ("Digital Signal Processor")), and at least one memory MD. This control device DC3 can therefore be implemented in the form of a combination of electrical or electronic circuits or components (or "hardware") and software modules (or "software"). For example, it can be a microcontroller.

[0043] The MD memory is RAM in order to store instructions for the implementation by the processor PR1 of at least part of the control method. The processor PR1 may comprise integrated (or printed) circuits, or several integrated (or printed) circuits connected by wired or wireless connections. An integrated (or printed) circuit is any type of device capable of performing at least one electrical or electronic operation.

[0044] In the example illustrated non-limitingly in Figures 1 and 2, the control device DC3 is part of the supervision computer CS. But this is not obligatory. Indeed, the control device DC3 could include its own dedicated computer, which is then coupled to the supervision computer CS, or could be part of another computer on board the vehicle V and providing at least one other function (possibly the machine computer CM), for example.

[0045] As illustrated non-limitingly in Figure 3, the (control) method, according to the invention, comprises a step 10-30 which is implemented each time that one is in a phase of recharging the battery BA by the electric motor MME by means of the second torque c2 delivered by the first coupling device DC1 from the first torque c1 supplied by the thermal motor MMT.

[0046] Step 10-30 of the method comprises a sub-step 10 in which, in the event of a transition between the parking position and an active position (for example the neutral position) of the gearbox BV during a recharging phase, the control device DC3 begins by prohibiting the coupling position of the first coupling device DC1 for a chosen duration dd.

[0047] Step 10-30 of the method also comprises a sub-step 30 in which, upon expiry of the chosen duration dd, one (the control device DC3) re-authorizes a new placement of the first coupling device DC1 in its coupling position.

[0048] It will be understood that the prohibition of the coupling position of the first coupling device DC1 causes the latter (DC1) to be placed in its decoupling position, and therefore the cessation of the delivery of the second torque c2 before the fall occurs. sudden pressure drop in the hydraulic circuit of the first coupling device DC1 (due to the hydraulic architecture of the GMP). As a result, the electric motor MME can no longer temporarily produce a third torque c3, which temporarily interrupts the recharging of the battery BA. Thus, when the pressure suddenly drops in the hydraulic circuit following the transition, there is no consequence. In particular, there is no longer any risk of shock and surge in the speed of the thermal motor MMT and collapse of the speed of the electric motor MME. Similarly, when the pressure suddenly returns to normal in the hydraulic circuit, this has no consequence because the first coupling device DC1 is still placed in its decoupling state, and therefore it does not deliver a second torque c2.Then, when the duration dd has elapsed, the first coupling device DC1 is again placed in its coupling state, and therefore it starts to deliver a second torque c2 from the first torque c1 even though there is no third torque c3, which makes it possible to avoid the generation of a shock. The invention therefore makes it possible to improve driving pleasure, and to prevent a constraint imposed by the hydraulic architecture of the powertrain from degrading the quality image of the vehicle V.

[0049] It will be noted that when the control device DC3 is part of the supervision computer CS, each prohibition of the coupling position and each authorization of (re)placement in the coupling position is generated by the control device DC3 and transmitted by the supervision computer CS to the computer CE (associated with the first coupling device DC1) by means of a message (or request).

[0050] For example, as soon as the control device DC3 prohibits the coupling position of the first coupling device DC1, it triggers a time delay having a duration equal to the chosen duration dd. Thus, when the time delay ends (chosen duration dd has elapsed) the control device DC3 immediately authorizes the placement of the first coupling device DC1 in its coupling position.

[0051] For example, in substep 10 of step 10-30 on (the control device DC3) can prohibit the coupling position immediately after being informed of the transition between the parking position and the active position of the gearbox BV.

[0052] Also for example, in a first embodiment, in step 10-30 one (the control device DC3) can determine the chosen duration dd as a function of an estimation of the current temperature of the oil circulating in the hydraulic circuit of the first coupling device DC1. This determination can, for example, be carried out in a sub-step 20 of step 10-30, as illustrated non-limitingly in FIG. 3.

[0053] The time required for the pressure to drop in the hydraulic circuit depends mainly on the viscosity of the oil, which in turn depends on the oil temperature. In other words, the higher the oil temperature, the faster the pressure drop will occur. We can therefore determine a time dd that is greater than the time required for the pressure to drop at the estimated oil temperature, in order to be certain that the pressure will have already dropped suddenly before the expiry of this time dd.

[0054] The estimation of the current temperature of the oil circulating in the hydraulic circuit can be provided by a sensor present in this hydraulic circuit. But this is not mandatory. Indeed, the estimation of the current temperature of the oil circulating in the hydraulic circuit can be provided by a sensor which is present in the gearbox BV, because the current temperature of the oil in the latter (BV) is equivalent to that of the oil in the hydraulic circuit. This estimation can, for example, be carried out in sub-step 10 or 20 of step 10-30.

[0055] Also for example, in step 10-30 (for example sub-step 20) one (the control device DC3) can determine the duration dd as a function of data which are stored in at least one correspondence table, for example previously determined in the factory (or test center) for a vehicle similar to vehicle V. This correspondence table establishes a correspondence between oil temperatures and durations (greater than the durations for obtaining a corresponding pressure drop).

[0056] In a second embodiment, in step 10-30 one (the control device DC3) can use a predefined duration dd, for example. In this case, the predefined duration dd corresponds to the longest possible duration for obtaining a pressure drop (i.e. in the presence of a very low oil temperature).

[0057] The invention offers several advantages including:

[0058] - improved driving pleasure (in particular by avoiding shocks or jolts and stalling of the MMT thermal motor),

[0059] - robustness of the control (or piloting) of the first DC1 coupling device thanks to the improvement of the monitoring of the second torque c2 and the optimal delivery of this second torque c2 in all life situations,

[0060] - an absence of degradation of a target optimization (for example relating to fuel consumption or pollution control),

[0061] - control of stored electrical energy,

[0062] - a reduction in the duration of the sliding phases of the first DC1 coupling device, allowing its lifespan to be increased and its cooling to be better controlled.

[0063] It will also be noted, as illustrated non-limitingly in Figure 2, that the supervision computer CS (or the computer of the control device DC3) can also include a mass memory MM1, in particular for storing each possible oil temperature, as well as any intermediate data involved in all its calculations and processing. Furthermore, this supervision computer CS (or the computer of the control device DC3) can also include an input interface IE for receiving at least each message signaling a transition during a recharging phase of the battery BA (by the electric motor MME) and each possible oil temperature, to use them in calculations or processing, possibly after having formatted and / or demodulated and / or amplified them, in a manner known per se, by means of a digital signal processor PR2. In addition, this supervision computer CS (or the computer of the control device DC3) can also include an output interface IS, in particular to deliver each message prohibiting the coupling position and each request for (re-authorization of) placement in the coupling position.

[0064] It will also be noted that the invention also proposes a computer program product (or computer program) comprising a set of instructions which, when executed by processing means of the electronic circuit (or hardware) type, such as for example the processor PR1, is capable of implementing the control method described above for controlling recharging phases of the battery BA of the vehicle V in the event of a transition of the gearbox BV between the parking position and an active position.

Claims

CLAIMS

1. Control method for a vehicle (V) comprising a powertrain comprising i) a thermal motor (MMT) capable of providing a first torque and of being coupled to a gearbox (BV), offering a parking position and at least one active position, by a coupling device (DC1) comprising a hydraulic circuit and capable, in a coupling position, of delivering a second torque from said first torque, and ii) an electric motor (MME) installed between said coupling device (DC1) and gearbox (BV) and capable in a recharging phase of recharging an associated battery (BA) in the presence of said second torque, characterized in that it comprises a step (10-30) in which, in the event of a transition between said parking and active positions during a recharging phase, said coupling position is prohibited for a chosen duration,then at the end of the latter, a new placement in said coupling position is re-authorized.

2. Method according to claim 1, characterized in that in said step (10-30) said coupling position is prohibited immediately after having been informed of said transition.

3. Method according to claim 1 or 2, characterized in that in said step (10-30) said chosen duration is determined as a function of an estimate of a current temperature of an oil circulating in said hydraulic circuit.

4. Method according to claim 3, characterized in that in said step (10-30) said duration is determined as a function of data stored in at least one table establishing a correspondence between oil temperatures and durations.

5. Method according to claim 1 or 2, characterized in that in said step (10-30) a predefined duration is used.

6. Computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing the control method according to one of claims 1 to 5, in a vehicle (V) comprising a powertrain comprising i) a thermal motor (MMT) capable of providing a first torque and of being coupled to a gearbox (BV), offering a parking position and at least one active position, by a coupling device (DC1) comprising a hydraulic circuit and capable, in a coupling position, of delivering a second torque from said first torque, and ii) an electric motor (MME) installed between said coupling device (DC1) and gearbox (BV) and capable in a recharging phase of recharging an associated battery (BA) in the presence of said second torque, for controlling recharging phases of said battery (BA) in the event of a transition between said parking and active positions.

7. Control device (DC3) for a vehicle (V) comprising a powertrain comprising i) a thermal motor (MMT) capable of providing a first torque and of being coupled to a gearbox (BV),providing a parking position and at least one active position, by a coupling device (DC1) comprising a hydraulic circuit and capable, in a coupling position, of delivering a second torque from said first torque, and ii) an electric motor (MME) installed between said coupling device (DC1) and gearbox (BV) and capable in a recharging phase of recharging an associated battery (BA) in the presence of said second torque, characterized in that it comprises at least one processor (PR1) and at least one memory (MD) arranged to carry out the operations consisting, in the event of a transition between said parking and active positions during a recharging phase, of prohibiting said coupling position for a chosen duration, then at the end of the latter of re-authorizing a new placement in said coupling position.,

8. Vehicle (V) comprising a powertrain comprising i) a thermal motor (MMT) capable of providing a first torque and of being coupled to a gearbox (BV), offering a parking position and at least one active position, by a coupling device (DC1) comprising a hydraulic circuit and capable, in a coupling position, of delivering a second torque from said first torque, and ii) an electric motor (MME) installed between said coupling device (DC1) and gearbox (BV) and capable in a recharging phase of recharging an associated battery (BA) in the presence of said second torque, characterized in that it further comprises a control device (DC3) according to claim 7.

9. Vehicle according to claim 8, characterized in that it is of the automobile type.

Images