FR3054189B1 - TORQUE CONTROL PROVIDED BY A MOTOR VEHICLE OF A PARALLEL HYBRID VEHICLE HAVING A MANUAL GEARBOX, ACCORDING TO THE CLUTCH - Google Patents

Abstract

A control device (DC) equips a vehicle (V) comprising a parallel hybrid transmission chain comprising at least one non-thermal power engine (MM) and a gearbox (BV) of manual type controlled by a gear lever ( LV) allowing a driver to select so-called thermal reports and so-called electrical reports, and coupled to a coupling member (OC) controlled by a clutch pedal (PE). This device (DC) is arranged, when an electrical ratio is selected, to determine at least one limiting torque as a function of a value representative of a current state of the clutch pedal (PE) and of minus a torque potential of the prime mover (MM), then to modify a torque setpoint that the driving machine (MM) must provide as a function of this determined limiting torque.

Description

The invention relates to the vehicles which are said to be parallel hybrids, and more specifically to the control of the transmission torque provided by the vehicles, which are said to be parallel hybrids, and more specifically to the control of the transmission torque supplied by the vehicles. non-thermal engines of such vehicles.

The term "parallel hybrid vehicle" here means a vehicle comprising a transmission chain comprising, on the one hand, a thermal engine, capable of being coupled to a manual type gearbox via a coupling member (for example a clutch), in order to drive a transmission train, and, secondly, at least one non-thermal driving machine associated with energy storage means and suitable for driving either another transmission train, or the same train that the engine if its connection with this train is located downstream of the gearbox. It will be noted that the invention concerns not only hybrid vehicles of the so-called HEV (Hybrid Electric Vehicle) type, but also hybrid vehicles of the so-called PHEV (Plugin Hybrid Electric Vehicle) type.

Furthermore, the term "non-thermal driving machine" here means a machine (or motor), electrical or hydraulic or compressed air, capable of providing transmission torque (for example to wheels) from the energy which is stored in energy storage means, such as a battery.

Currently, almost all parallel hybrid vehicles include an automated transmission chain (that is to say a robotized gearbox (automatic (or BVA), manual driven (or BVMP), double clutch (or DCT) This arrangement makes it possible to choose the transmission mode (electrical and / or thermal), and to manage the respective coupling members of the heat engine and the prime mover as well as the transmission ( selection and commitment of the gear ratio between the engine and, for example, the wheels of the associated train) by means of an algorithm that interprets the driver's will based on, in particular, the speed of the vehicle, the depression of the accelerator pedal and the depression of the brake pedal.

As known to those skilled in the art, this type of automated transmission chain is quite expensive. As a result, it has recently been proposed to use a gearbox of manual type controlled by a gear lever allowing the driver to select, on the one hand, so-called thermal reports, and, on the other hand, so-called electrical reports. This makes it possible to reduce the cost of the parallel hybrid transmission chain and to introduce an electric operating mode of the vehicle without additional intervention of the driver and without the addition of an actuator or a specific algorithm, while offering the main benefits of an automated parallel hybrid transmission chain (and in particular a so-called ZEV (zero emissions of pollutant and CO2) and a complement of power (or "boost")).

Moreover, this type of transmission chain imposes on the driver two different behaviors depending on whether the operating mode is thermal or all electrical (or ZEV). Indeed, in the thermal operating mode, the driver can dose the amount of transmission torque supplied (for example to the wheels) by the engine by means of the clutch pedal and the accelerator pedal, while in the all-electric mode of operation the driver can not measure the amount of the transmission torque supplied (for example to the wheels) by the prime mover by means of the accelerator pedal. This duality of behavior may be disruptive for some drivers, or may lead to pedal actuation errors, especially for those who have never driven a hybrid vehicle and therefore have acquired driving reflexes adapted to pure thermal vehicles. . The purpose of the invention is in particular to improve the situation.

It proposes for this purpose a control method for a vehicle comprising a parallel hybrid transmission chain comprising at least one non-thermal driving machine and a gearbox of manual type, controlled by a gear lever allowing a driver to select so-called thermal reports and so-called electrical reports, and coupled to a coupling member controlled by a clutch pedal.

This method is characterized in that it comprises a step in which, when an electrical ratio is selected, at least one limiting torque is determined as a function of a value representative of a current state of the pedal. clutch and at least one torque potential of the prime mover, and then modifies a torque setpoint that must be provided by the prime mover as a function of this determined limiting torque.

Thus, in the all-electric mode of operation the driver can now dose, if he wishes, the amount of the transmission torque supplied (for example to the wheels) by the prime mover by means of the clutch pedal and the pedal accelerator, as it does in the thermal operation mode.

The control method according to the invention may comprise other characteristics that can be taken separately or in combination, and in particular: in its step, it is possible to determine the limiting torque as a function of the value and of a minimum torque potential; that can be provided by the prime mover for a brake torque, or the value and maximum torque potential that the prime mover can provide for engine torque. As a variant, in its step it is possible to determine the limiting torque as a function of the value and of a predefined minimum torque potential for a brake torque, or of the value and a maximum predetermined torque potential for a driving torque. ; in its step, it is possible to determine a minimum limitation torque as a function of the value and the minimum torque potential, and a maximum limiting torque as a function of the value and the maximum torque potential; In its step, when the value is representative of an open state of the coupling member, the minimum limiting torque and the maximum limiting torque can be selected equal to zero; In its step, when the value is representative of a closed state of the coupling member, the minimum limiting torque can be chosen equal to the minimum torque potential, and the maximum limiting torque can be chosen equal to the potential of maximum torque; In its step, when the value is representative of a sliding state of the coupling member, the minimum limiting torque can be proportional to the minimum torque potential, and the maximum limiting torque can be proportional to the maximum torque potential . As a variant, in its step, when the value is representative of an intermediate state between an open state and a closed state of the coupling member, the minimum limitation torque may be a function of the (possibly proportional to) the minimum torque potential. , and the maximum limiting torque can be a function of the (possibly proportional to) the maximum torque potential. The invention also proposes a control device intended to equip a vehicle comprising a parallel hybrid transmission chain comprising at least one non-thermal driving machine and a gearbox of manual type, controlled by a gear lever allowing a driver to select so-called thermal reports and so-called electrical reports, and coupled to a coupling member controlled by a clutch pedal.

This device is characterized in that it is arranged, when an electrical ratio is selected, to determine at least one limiting torque as a function of a value representative of a current state of the clutch pedal and of the at least one torque potential of the prime mover, then to modify a torque setpoint that the driving machine must supply as a function of this determined limiting torque. The invention also proposes a vehicle, possibly of automobile type, and comprising, on the one hand, a parallel hybrid transmission chain comprising at least one non-thermal driving machine and a gearbox of manual type, controlled by a gear lever. allowing a driver to select so-called thermal ratios and so-called electrical ratios, and coupled to a coupling member controlled by a clutch pedal, and, secondly, a control device of the type of that presented above . Other features and advantages of the invention will appear on examining the detailed description below and the accompanying drawings, in which: FIG. 1 diagrammatically and functionally illustrates a vehicle comprising a parallel hybrid transmission chain and a supervision computer of the transmission chain equipped with a control device according to the invention, and - Figure 2 schematically illustrates an example of a speed selection grid associated with a gear lever of a vehicle of the type illustrated. in Figure 1, and an example of state ranges of a clutch pedal. The object of the invention is in particular to propose a control method, and an associated DC control device, for controlling the transmission torque supplied (for example to the wheels) by at least one non-thermal MM driving machine of a hybrid vehicle. parallel V, manual type BV gearbox.

In what follows, it is considered, by way of non-limiting example, that the vehicle (parallel hybrid) V is automotive type. This is for example a car. But the invention is not limited to this type of parallel hybrid vehicle. It concerns indeed any type of parallel hybrid vehicle land or sea (or fluvial).

FIG. 1 shows schematically a vehicle V comprising a parallel hybrid transmission chain, a supervision computer CS, and a DC control device according to the invention.

The transmission chain (parallel hybrid) comprises a hybrid powertrain (or GMP) whose operation is supervised (or managed) by the supervision computer CS, a first coupling device OC, a gearbox BV of the manual type, and a possible means of coupling / decoupling MC.

The hybrid GMP comprises in particular an MT heat engine, a non-thermal MM prime mover, and MS energy storage means.

Here is meant by "thermal engine MT" an engine consuming fuel or chemicals.

The thermal engine MT comprises a crankshaft (not shown) which is fixedly attached to a motor shaft in order to drive the latter in rotation.

The gearbox BV (manual) comprises at least one input shaft (or primary) intended to receive the torque produced by the heat engine MT via the coupling member OC, and an output shaft intended to receive this torque via the input shaft for communicating with a transmission shaft to which it is coupled and which is coupled indirectly to the wheels (here of the TV front train of the vehicle V), preferably via a differential before DV.

For example, the coupling member OC is a clutch comprising a flywheel fixedly secured to the drive shaft and a clutch disc fixedly secured to the input shaft of the gearbox BV.

This coupling member OC may be placed either in an open (or disengaged) state in which it totally decouples the thermal engine MT of the gearbox BV, or in a closed (or engaged) state in which it couples the heat engine MT to the gearbox BV, either in at least one intermediate (or sliding) state in which it begins to uncouple / couple the heat engine MT from / to the gearbox BV. The state in which the coupling member OC is placed is determined by a sensor CE which is coupled thereto (OC). This sensor CE delivers a value ve which is representative of the current state of the clutch pedal PE. For example, such a sensor CE may be proportional type. It is then arranged to measure the percentage of depression of the clutch pedal PE. In this case, and as illustrated schematically in the left-hand part of FIG. 2, the open state corresponds to a depression between a = 0% and b%, the sliding state corresponds to a depression lying between b% and c%. , and the closed state corresponds to a depression of between c% and d = 100%. For example, and not limitation, b may be between 30% and 50% and c may be between 70% and 80%. It will be noted that, in one variant, several sliding states, respectively providing different coupling / decoupling, may be accessible. In other words, the threshold c and possibly the threshold b can be variable, for example as a function of the torque potentials of the prime mover MM.

The operation of the gearbox BV is controlled by a shift lever LV which is actuable by the driver of the vehicle V. More specifically, this shift lever LV allows the driver to select at least so-called thermal reports (dedicated to the modes of operation using the thermal engine MT) and so-called electrical reports (dedicated to the operating mode using the only power engine MM).

FIG. 2 schematically illustrates an example of a speed selection grid associated with a speed lever LV of a vehicle V of the type shown in FIG. 1. This example of a grid is adapted to a BV manual transmission with three odd thermal ratios (1, 3 and 5), three even thermal ratios (2, 4 and 6), a reverse thermal ratio R, and a neutral line LN giving access to a neutral state N of the BV manual gearbox, E1 electric forward and E2 electric reverse. It will be understood that when the shift lever LV is placed in the position E1 by the driver, this means that the latter wants the transmission chain to operate forward exclusively with the prime mover MM. Similarly, when the shift lever LV is placed in the E2 position by the driver, it means that the latter wants the transmission chain to operate in reverse exclusively with the prime mover MM. In all other positions, the driver wants the transmission chain to operate with at least the engine MT, except when the gearbox BV is in a neutral state (or neutral).

The non-thermal engine MM is intended to provide torque to move the vehicle V, either alone or in addition to the heat engine MT. Therefore, it may for example be an electric motor, a hydraulic machine, or a pneumatic machine.

In the following, by way of non-limiting example, the driving machine MM is considered to be of the electric type. But as indicated above this motor machine MM could be of another type.

The driving machine MM is coupled to energy storage means MS, possibly via an inverter (not shown). In view of the preceding paragraph, the energy storage means MS are of the electric type. For example, they are arranged in the form of a battery of low voltage type (for example and not limited to about 220 V or 100 V or 48 V). Any coupling / decoupling means MC may be responsible for coupling / decoupling the prime mover MM to a transmission shaft to communicate the torque produced by the energy stored in the storage means MS. . This transmission shaft is responsible for rotating the wheels of a train. This possible means of coupling / decoupling MC is for example a jaw mechanism or a clutch.

It will be noted that in the embodiment illustrated in non-limiting manner in FIG. 1, the coupling / decoupling means MC is responsible for coupling / decoupling the driving machine MM to a transmission shaft which is different from the one to which it is connected. coupled the thermal engine MT (via the coupling member OC). This coupling / decoupling is done here on the rear train TR of the vehicle V, via a rear differential DR, as an illustrative example. However, in an embodiment variant not illustrated, the coupling / uncoupling means MC could be responsible for coupling / decoupling the driving machine MM to / from the transmission shaft with which the thermal engine MT is coupled (via the coupling member OC ), downstream of the gearbox BV.

In another non-illustrated embodiment (referred to as "wheel motors"), MM motor machines could be coupled to at least two wheels, directly (that is, without the need to use a coupling means). MC decoupling), to ensure traction or energy recovery by electric braking while ensuring the stability of the vehicle.

The transmission chain also comprises an electric machine AD (starter or alternator-starter) which is coupled to the thermal engine MT, in particular to launch it during a start. This electric machine AD can be coupled to energy storage means MS 'which can be arranged in the form of a battery (servitude), for example of the very low voltage type (for example 12 V, 24 V or 48 V ), as illustrated in non-limiting manner in FIG. 1. But in a variant this electric machine AD could be coupled to the energy storage means MS.

It is also possible to provide a DC / DC type CV converter between the energy storage means MS and the energy storage means MS ', so as to supply power to the on-board network of the vehicle V if the electric machine AD operates under 220 V.

As indicated above, the invention proposes to implement in the vehicle V a method for controlling the transmission torque which is (here) provided to the rear wheels by the driving machine MM of the vehicle V.

Such a method can be implemented by a DC control device. In the nonlimiting example illustrated in FIG. 1, the control device DC forms part of the supervision computer CS. This results from the fact that the supervision computer CS manages, here, the heat engine MT and the motor machine MM. But this is not obligatory. This (control) device DC could indeed be a device coupled to the supervision computer CS, directly or indirectly. It could be part of another computer or device. Therefore, the device (control) DC can be realized in the form of software modules (or computer or "software"), or a combination of electronic circuits (or "hardware") and software modules.

The method according to the invention comprises a step which is implemented when an electrical ratio (here E1 or E2) is selected. In this step, the (DC device) determines a limiting torque Cüm as a function of the value ve (which is representative of the current state of the clutch pedal PE) and of at least one torque potential of the driving machine MM. Then, (the DC device) modifies a torque setpoint ccmm that must be supplied by the prime mover MM as a function of this determined limiting torque C | jm.

In what follows reference cc'mm the modified torque setpoint that will use the supervision computer CS to drive the prime mover MM.

Thus, when the driver has chosen to select an electric gear, he can, if he wishes, behave in the same way as if he had selected a thermal report, namely to measure the electric torque that is transmitted to the wheels. acting on the clutch pedal PE.

The torque setpoint ccmm to be supplied by the prime mover MM is determined internally by the supervision computer CS based, at least, on the will of the driver. This will of the driver is a function, in particular, of the current speed of the vehicle V, the depression of the accelerator pedal PA and the depression of the brake pedal.

It will be noted that in the process step (the DC device) can, for example, modify the torque setpoint ccmm that the driving machine MM must supply in two ways depending on whether the torque is a driving torque or a brake torque.

For motor torques (and thus> 0), the modified torque setpoint cc'mm may be equal to ccmm if C max is greater than ccmm, and to max cnm if C max is less than ccmm-C | jm max is maximum limiting torque in the motor case.

For the brake torques (and therefore <0), the modified torque setpoint cc'mm may be equal to ccmm if Cnm min is less than ccmm, and to C | jm min if Cummin is greater than ccmm- Cummin is the minimum limitation torque in the case of a brake torque. It is here "maximal" in absolute, but minimal because negative.

It will also be noted that in the process step (the DC device) can, for example, determine the limiting torque C | jm as a function of the value ve, a minimum torque potential pcmin mm (1) that can supplying the prime mover MM at the instant t considered and a maximum torque potential pcmax mm (î) that can be supplied by the prime mover MM at the instant t considered.

The minimum torque potential pcmin mm (1) and the maximum torque potential pcmax mm (O are determined internally by the supervision computer CS as a function mainly of the charging power (for pCminMM (t)) and the power of the discharge (for pcmaXMM (t)) energy storage means MS and minimum torque potentials pcmin mm and maximum intrinsic pcmaXMM of the prime mover MM.

In an alternative embodiment, in the process step (the DC device) can, for example, determine the limiting torque C | jm as a function of the value ve, a predefined minimum torque potential pcmin pr (and therefore independent of the time t considered) and a predefined maximum torque potential pcmaXpr (and therefore independent of the time t considered).

For example, in the two embodiments described above, (the device DC) can, in the step of the method, determine a minimum limiting torque Cüm min as a function of the value ve and the minimum torque potential pcmin mm (î) or pcmin pr, and a maximum limiting torque C | jm max as a function of the value ve and the maximum torque potential pcmax mm (î) or pCmax pr-

For example, the DC device can determine a minimum limiting torque C | jm min equal to pcminMM (t) * ve / 100 and a maximum limiting torque Clim max equal to pcmaXMM (t) * ve / 100.

Also, for example, the DC device can determine a minimum limiting torque C min, equal to pc min pre / 100 (<0), and a maximum limiting torque cnm max equal to pcmax expected / 100 (> 0).

Then (the DC device) can determine the limiting torque C | jm as a function of at least the minimum limiting torque Ciimmin (for the brake torques) or the maximum limiting torque Cum max (for the driving torques). More specifically, the limiting torque C | jm may be chosen equal to the minimum limiting torque C | jm min for a brake torque and may be chosen equal to the maximum limiting torque Ciimmax for a motor torque.

For example, in the step of the method, when the value ve is representative of the open state of the coupling member OC, the minimum limiting torque C | min min and the maximum limiting torque C | jm max can be choose equal to zero.

Also, for example, in the process step, when the value ve is representative of the closed state of the coupling member OC, the minimum limiting torque Cmin | min may be chosen equal to the minimum torque potential pcmin mm. (i) or pcmin pr, and the maximum limiting torque Cüm max can be chosen equal to the maximum torque potential pcmaxMM (t) or pcmaxpr ·

Also for example, in the step of the method, when the value ve is representative of the sliding state of the coupling member OC, the minimum limiting torque Cμm min can be a function of (possibly proportional to) the minimum torque potential pcmin mm (î) or pcmin pr, and the maximum limiting torque C | jm max can be a function of the (possibly proportional to) the maximum torque potential pcmax mm (î) or pcmax pr. The function is not necessarily linear (or proportional).

In the case of a proportionality one can have C | jm min = A * pcmin mm (0 OR C | im min - A pCmin pr, and C | im max - A pCmax MM (t) OR C | im max - A pCmax pr, where is a predefined proportionality constant.

As a variant, in the step of the method, when the value ve is representative of an intermediate state (among several) between the open state and the closed state of the coupling member OC, the minimum limiting torque C | jm min may be proportional to the minimum torque potential pcmin mm (î) or pcmin pr, this proportionality being defined by a first proportionality factor f1 (ve) which is a function of the value ve, and the maximum limiting torque dim max may be proportional to the maximum torque potential pcmax mm (î) or pcmax pr, this proportionality being defined by a second proportionality factor f2 (ve) which is a function of the value ve. In other words, we have ciim min = f1 (ve) * pcmin mm (î) or ciim min = f1 (ve) * pcmin pr, and C | im max = f2 (VO) pCmax MM (t) OR C | jm max = f2 (VO) pCmaxpr-

In the latter case, the first f1 (ve) and second f2 (ve) proportionality factors can be either identical for the same value ve, or different from one another for the same value ve. The invention offers several advantages, among which: - the possibility for the driver, during the stopping or starting phases of the vehicle or during maneuvers in forward or rear electric, to use the clutch pedal to couple / decouple "virtually" the non-thermal driving machine in order to dose the electric torque supplied to the wheels, which avoids disrupting his driving habits with a manual gearbox, - the possibility for the driver, during a change of a thermal ratio towards an electrical ratio, to find the same behavior as in any thermal, because when it re-engages it can dose the electric acceleration to the wheels thanks to the accelerator and clutch pedals, - a very weak impact on the control of the GMP, because transient torque demands from all-electric mode to all-thermal mode or all-thermal mode to all-electric mode are powered by the driver using the accelerator and clutch pedals.

Claims (10)

1. Control method for a vehicle (V) comprising a parallel hybrid transmission chain comprising at least one non-thermal power engine (MM) and a gearbox (BV) of manual type controlled by a gear lever (LV) allowing a driver to select so-called thermal ratios and so-called electrical ratios, and coupled to a coupling member (OC) controlled by a clutch pedal (PE), characterized in that it comprises a step in which, when an electrical ratio is selected, at least one limiting torque is determined as a function of a value representative of a current state of said clutch pedal (PE) and of at least one torque potential of said driving machine (MM), then modifies a torque setpoint that must provide said engine (MM) according to said determined limiting torque. 2. Method according to claim 1, characterized in that in said step said limiting torque is determined as a function of said value and a minimum torque potential that can be provided by said prime mover (MM) for a brake torque, or of said value and a maximum torque potential that can be provided by said prime mover (MM) for a driving torque. 3. Method according to claim 1, characterized in that in said step said limiting torque is determined as a function of said value and a predefined minimum torque potential for a brake torque, or said value and a potential. predefined maximum torque for a motor torque. 4. Method according to one of claims 2 and 3, characterized in that in said step is determined a minimum limitation torque according to said value and said minimum torque potential, and a maximum limiting torque according to said value and said maximum torque potential. 5. Method according to claim 4, characterized in that in said step, when said value is representative of an open state of said coupling member (OC), said minimum limiting torque and maximum limiting torque are equal to zero. 6. Method according to one of claims 4 and 5, characterized in that in said step, when said value is representative of a closed state of said coupling member (OC), said minimum limitation torque is equal to said torque potential. minimum, and said maximum limiting torque is equal to said maximum torque potential. 7. Method according to one of claims 4 to 6, characterized in that in said step, when said value is representative of a sliding state of said coupling member (OC), said minimum limitation torque is proportional to said torque potential minimum, and said maximum limiting torque is proportional to said maximum torque potential. 8. Method according to one of claims 4 to 6, characterized in that in said step, when said value is representative of an intermediate state between an open state and a closed state of said coupling member (OC), said pair of minimum limitation is proportional to said minimum torque potential, this proportionality being defined by a first proportionality factor according to said value, and said maximum limiting torque is proportional to said maximum torque potential, this proportionality being defined by a second proportionality factor function of said value. 9. Control device (DC) for a vehicle (V) comprising a parallel hybrid transmission chain comprising at least one non-thermal power engine (MM) and a gearbox (BV) of manual type controlled by a gear lever (LV) allowing a driver to select so-called thermal ratios and so-called electrical ratios, and coupled to a coupling member (OC) controlled by a clutch pedal (PE), characterized in that it is arranged, when an electrical ratio is selected to determine at least one limiting torque as a function of a value representative of a current state of said clutch pedal (PE) and at least one torque potential of said driving machine (MM), then to change a torque setpoint that must provide said engine (MM) according to said determined limiting torque. 10. Vehicle (V) comprising a parallel hybrid transmission chain comprising at least one non-thermal power engine (MM) and a gearbox (BV) of manual type, controlled by a gear lever (LV) allowing a driver to select so-called thermal reports and so-called electrical reports, and coupled to a coupling member (OC) controlled by a clutch pedal (PE), characterized in that it further comprises a control device (DC) according to the claim 9.