FR2991953A1 - Method for assisting coupling/decoupling of electric machine of hybrid car circulating in environment, involves coupling machine to recover electrical energy by braking and to increase torque, in presence of environment information - Google Patents

Abstract

The method involves coupling an electric machine (ME) to recover electrical energy by braking and to increase torque offered by a transmission chain, in presence of environment information indicating need for deceleration of a hybrid vehicle (V) and indicating need for acceleration of the vehicle, respectively. The machine is decoupled in presence of the environment information indicating a speed limit and current speed of the vehicle around stabilized speed and/or environment information indicating constant distance between the vehicle and a preceding vehicle. The environment information is selected in a group including information of indication of lanes, information of type of circulation zone, anti-collision information relative to a preceding vehicle from the vehicle, and road information and weather information. The information of indication of lanes is chosen from a group including indications of control panels, color in course of a traffic light, and markings out of ground. The information of anti-collision is selected in a group including estimated speed of the preceding vehicle, distance separating the vehicle from the preceding vehicle, and time estimated before collision with the preceding vehicle. Independent claims are also included for the following: (1) a device for assisting coupling/decoupling of a machine with a transmission chain of a hybrid vehicle circulating in an environment (2) a hybrid vehicle.

Description

TECHNICAL FIELD The invention relates to vehicles which are said to be hybrid because they comprise a transmission chain. comprising a heat engine and at least one machine (or motor), electric or hydraulic or compressed air, associated with (e) energy storage means, and more precisely the aid to decision making coupling / decoupling the machine from the transmission chain of such hybrid vehicles. As known to those skilled in the art, some hybrid vehicles, possibly of the automotive type, comprise a device which is intended to help their computer managing the transmission chain make decisions to couple or decoupling their machine (or motor), possibly electrical, to their transmission chain. Note that any type of coupling / decoupling is concerned here, including those by clutch and clutch. Such assistance devices are usually responsible for providing such coupling or decoupling as a function of information relating to the vehicle in question, and more precisely chosen from the depression of the accelerator pedal, the depression of the pedal brake, the current speed of the vehicle, the current inclination of the vehicle, and a constraint of use of the electric motor and / or the engine. Each coupling / decoupling proposal is transmitted to the transmission chain management computer, which then decides to follow it or to reject it according to its own constraints, possibly temporary. In general, a coupling may have the objective of minimizing the fuel consumption by the heat engine, for example by recovering the electrical energy in the braking phases, and / or increasing the performance of the engine. hybrid vehicle, for example by adding to the torque produced by the engine of the torque offered by the electric motor during a displacement. The current coupling / decoupling proposals are not entirely satisfactory. Indeed, they can lead to a permanent coupling for relatively long periods, especially when the speed of the vehicle is stabilized, which, on the one hand, induces energy losses by dissipation (typically several kilowatts at high speed) of the the loss moment of the electric motor, and, secondly, can damage the electric motor when it has a maximum speed beyond which decoupling is necessary. In addition, in an all-electric mode of operation (or ZEV ("Zero Emission Vehicle")), each decoupling proposal can be systematically rejected when the speed of the vehicle is below a threshold (for example equal to 50 km / h). In addition, the depression of the accelerator pedal and the depression of the brake pedal being two important parameters in the decision making coupling / decoupling, it often happens that they result from a decision at least partially erroneous taken by the driver, for example due to a bad and / or late taking into account of the environment of his vehicle. Thus, a driver may, for example, decide to accelerate even though there is locally a speed limit that will be exceeded following this acceleration. Similarly, a driver can, for example, continue to depress the accelerator pedal even as his vehicle is approaching a tricolor traffic light that has just turned red without him noticing.

The invention is therefore particularly intended to improve the situation by taking into account information representative of the environment of the hybrid vehicle, for example so as to anticipate actions of the driver and / or prevent the driver from making erroneous decisions . More specifically, the invention proposes in particular a method, on the one hand, intended to aid the decision making of coupling / decoupling of at least one machine (possibly electrical) to a transmission chain of a hybrid vehicle circulating in a environment, and, on the other hand, to propose a coupling / decoupling of the machine to the transmission chain based on information that is representative of this environment. It is henceforth possible not only to anticipate a decision that a driver should make if he knew the environmental information available, but also to correct very quickly a decision made by a driver following a misinterpretation or partial interpretation of the information available environment, and thus to limit the changes of state of the chain of transmission. The aid method according to the invention may comprise other characteristics which can be taken separately or in combination, and in particular: a coupling of the machine capable of recovering electric energy by braking can be proposed, in the presence of environmental information that signal a need for slowing down the vehicle; It is possible to propose a coupling of the machine, capable of increasing a torque offered by the transmission chain, in the presence of environmental information which signals a need for acceleration of the vehicle; it may also consist in proposing the coupling / decoupling also in function of information relating to the vehicle and chosen from (at least) the depression of the accelerator pedal of the vehicle, the depressing of the brake pedal the vehicle, the current speed of the vehicle, the current inclination of the vehicle, and a constraint of use of the machine and / or a heat engine of the transmission chain; the environmental information may be selected from (at least) traffic lane information, traffic zone type information, collision avoidance information relating to a vehicle preceding the vehicle, traffic information and meteorological information; the traffic lane signaling information may be selected from (at least) traffic sign indications, the current color of a traffic light (two-color or three-color), and markings on the ground; the collision avoidance information can be chosen from (at least) the estimated speed of the vehicle preceding the vehicle in question, the distance separating the vehicle considered from a vehicle which precedes it, and the estimated time before a collision with the vehicle preceding the vehicle considered; it is possible to propose a decoupling of the machine in the presence of environmental information indicating a speed limitation and a running speed of the vehicle considered stabilized around this speed limitation and / or environmental information signaling a substantially constant distance between the vehicle considered and a vehicle in front and a vehicle speed considered substantially constant. The invention also proposes a device, on the one hand, intended to aid the decision making of coupling / decoupling of at least one machine (possibly electric) to a transmission chain of a hybrid vehicle circulating in an environment, and on the other hand, arranged to propose a coupling / decoupling of the machine to the transmission chain based on information that is representative of this environment. The invention also proposes a hybrid vehicle, possibly of automobile type, and comprising a transmission chain, comprising at least one machine (possibly electric) and a heat engine, and a help 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 attached drawing, in which the single figure schematically and functionally illustrates a hybrid vehicle comprising a transmission chain and a supervisor. transmission chain equipped with a device according to the invention. The object of the invention is to propose a method of assistance, and the associated assistance device D, intended to aid the decision making of coupling / decoupling of at least one (possibly electric) machine ME to a transmission chain. of a hybrid vehicle V. In what follows, it is considered, by way of non-limiting example, that the hybrid vehicle V is automotive type. This is for example a car. But the invention is not limited to this type of hybrid vehicle. It concerns in fact any type of terrestrial or maritime (or fluvial) or aeronautical hybrid vehicle, having a transmission chain comprising at least one heat engine MT and at least one ME machine coupled to MS energy storage means .

Furthermore, it is considered in the following, by way of non-limiting example, that the machine ME is of the electric type. But the invention is not limited to this type of machine. Thus, it also relates to engines (or machines) hydraulic or compressed air, as they allow to recover energy. FIG. 1 shows schematically a hybrid vehicle V comprising a transmission chain, a first supervisor (or calculator) SC capable of supervising (or managing) the operation of the transmission chain, a second supervisor (or calculator). SB capable of supervising (or managing) the operation of the gearbox BV, and a device D of aid according to the invention. The transmission chain comprises, here, a heat engine MT, an engine shaft AM, a main clutch EM, a gearbox BV, a first transmission shaft AT1, at least one machine ME (here an electric motor), a shaft Ai, coupling / decoupling means CR for the electric motor ME, and a second transmission shaft AT2. For example, the first transmission shaft AT1 is responsible for driving in rotation the front wheels of the vehicle V, while the second transmission shaft AT2 is responsible for driving the rear wheels of the vehicle V in rotation. But the opposite is also possible. The thermal engine MT comprises a crankshaft (not shown) which is fixedly attached to the drive shaft AM to drive the latter (AM) in rotation. The gearbox BV comprises at least one input (or primary) shaft AE and an output shaft AS intended to be coupled to each other. The input shaft AE is designed to receive the engine (thermal) torque via the main clutch EM. The output shaft AS is intended to receive the motor torque via the input shaft AE in order to communicate it to the first transmission shaft AT1 to which it is coupled and which is coupled indirectly to the wheels (here) before the vehicle V. The input shaft AE and the output shaft AS each comprise sprockets (not shown) which are intended to participate selectively in the definition of the different selectable speeds of the gearbox BV.

In the nonlimiting example illustrated, the clutch EM comprises in particular a VM flywheel which is fixedly secured to the drive shaft AM and a clutch disc DE which is fixedly secured to the input shaft AE. It will be noted that the gearbox BV can be automated or not.

Therefore, it may be an automatic transmission, a manual gearbox controlled or not, or a double clutch gearbox (or DCT). For example, the electric motor ME rotates the shaft Al which is coupled to the coupling / decoupling means CR which is itself coupled to the second transmission shaft AT2. This means of coupling / decoupling CR is for example a jaw mechanism or a clutch. Note that in the non-limiting example illustrated in the single figure, the transmission chain also comprises an electric machine AD which is, for example, an alternator-starter responsible in particular for launching the heat engine MT to allow it to start , including the presence of an automatic stop and start control system (or "stop and start"). This alternator-starter AD is responsible for driving in rotation a rotor shaft (or armature) A2 which is here secured to a free wheel RL to be coupled on order to a third pinion or a third coupling wheel RC3 which permanently engages a fourth pinion or a fourth RC4 coupling wheel secured to the drive shaft AM. The operations of the thermal engine MT, the electric motor ME and the alternator-starter AD are controlled by the first supervisor SC which can be in the form of a computer (preferably dedicated). The operation of the gearbox BV is, for example, controlled by the second supervisor SB which can be in the form of a computer (preferably dedicated). As indicated above, the invention proposes to implement in the vehicle V a method for assisting decision making coupling / decoupling of the electric motor ME to the transmission chain, and more specifically to the second transmission shaft AT2. Such a method can be implemented by the aid device D. In the nonlimiting example illustrated in FIG. 1, the assistance device D is part of the first supervisor (of the transmission chain) SC. But this is not obligatory. This (help) device D could indeed be an equipment that is coupled with the first supervisor SC, directly or indirectly. Therefore, the help device D 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 aid method, according to the invention, consists in proposing, here to the first supervisor SC, a coupling / decoupling of the electric motor ME to / of the transmission chain as a function of information which is representative of this environment. By "environmental information" is meant herein information which relates to the taxiway on which the vehicle V is traveling and to adjacent traffic lanes and to vehicles which are located on that lane or on these neighboring traffic lanes. It is therefore not information about the vehicle V and the state in which it is at the moment considered. Note, however, that the method can also take into account such information relating to the vehicle V (and its state), including the depression of its accelerator pedal, the depression of its brake pedal, its speed in course, its inclination in course (because of the slope of the taxiway on which it moves), and a constraint of use of the electric motor ME (such as a temperature limitation of use) and / or the MT heat engine. For example, when the inclination of the vehicle V is important, a coupling of the electric motor ME may be proposed to increase the traction of this vehicle V.

Thanks to the invention, it is now possible to anticipate a decision that a driver should make if he were aware of the environmental information available to the assistance device D, but also to correct very quickly a decision taken by a driver when he is in pain. interpreted the available environment information, which makes it possible to limit the state changes of the transmission chain. Preferably, the environment information is selected from at least traffic lane signaling information, traffic zone type information, collision avoidance information relating to a vehicle which precedes the vehicle V under consideration, road information and weather information. It should be noted that this environment information can be obtained by the vehicle V by any means known to those skilled in the art, and in particular by means of on-board acquisition means (such as for example cameras and radars) coupled to shape recognition means, and / or an onboard navigation aid application (possibly of the GPS type) having its own database and / or capable of obtaining information by means of waves from databases. For example, the traffic lane signaling information may be selected from, at least, traffic sign indications (and in particular speed limit signs, stop signs and "give way" signs, signs indicating direction or destination or retarder), the color in the course of a traffic light (two-color or three-color), and markings on the ground (and in particular continuous lines, broken lines, and inscriptions of signaling (stop or directional arrows)). This information can itself make it possible to define other information that may be used by the aid device D, such as, for example, and without limitation, the speed error with respect to a speed limitation. This information is likely to influence the traffic on the path taken by a driver with his vehicle V, and, which can be known by the vehicle V earlier than by its driver, they can be advantageously used to anticipate an action such as coupling or decoupling of the electric motor ME. By way of example, when the vehicle V arrives at a traffic light that has turned red or a stop or a new speed limit that is more restrictive than the previous one, this should cause the driver to relax (at least less partial) of the accelerator pedal and / or a pressure on the brake pedal, and thus lead to the definition of a new negative torque setpoint and no longer positive. An anticipation of coupling will therefore advantageously make it possible to use the electric motor ME faster to recover electrical energy resulting from the braking and thus to reduce fuel consumption. Likewise, when the vehicle V comes to the level of a traffic light that has just gone green or a new speed limitation less restrictive than the previous one, this should cause the driver a strong support on the pedal throttle and release the brake pedal, and thus lead to the definition of a new setpoint (plus) positive torque. An anticipation of coupling will therefore advantageously make it possible to use the electric motor ME more rapidly in order to offer more torque to the transmission chain and thus to reduce the fuel consumption due to the reduced force required of the thermal engine MT. The collision avoidance information may be provided by a radar of an onboard collision avoidance system and chosen, for example, from, at least, the estimated speed of the vehicle preceding the vehicle V considered, the distance separating the vehicle V considered from a vehicle preceding it, and the estimated time before a collision with the vehicle preceding the vehicle V considered. This information is likely to influence the traffic on the path taken by a driver with his vehicle V, and, which can be known by the vehicle V earlier than by its driver, they can be advantageously used to anticipate an action such as coupling or decoupling of the electric motor ME. By way of example, when the preceding vehicle is near and has a speed lower than that of the vehicle V considered (or is totally stopped), for example because the latter (V) arrives at a tricolor red light or at an intersection associated with a "give way" when a priority vehicle is traveling on a perpendicular lane, this should cause the driver to release (at least partially) the accelerator pedal and / or brake pedal, and therefore lead to the definition of a new setpoint of negative torque and no longer positive. A coupling anticipation will therefore advantageously make it possible to use the electric motor ME more quickly to recover electrical energy resulting from the braking and thus to reduce fuel consumption. Likewise, when the preceding vehicle accelerates, for example because it enters a zone with a less restrictive speed limit, a coupling of the electric motor ME can be proposed to define a new (plus) positive torque setpoint, because that there is a high probability that the driver of the vehicle V acts very soon like that of the preceding vehicle. This anticipation of coupling will advantageously make it possible to use the electric motor ME more quickly in order to offer more torque to the transmission chain and thus to reduce the fuel consumption due to the reduced effort required of the thermal engine MT. The traffic zone type information may, for example, be selected from, at least, an urban area (road), a peri-urban area (road, highway) and an extra-urban area (road, road, highway). Current meteorological information may, for example, be provided by a meteorological application, possibly remotely searchable. This is for example information on the current time on the traffic lane (rain, wind, snow, ice, sleet, hail, flood, storm), which are likely to influence traffic on the path taken by a driver with his vehicle V. It will be understood that such information can be known by the vehicle V earlier than its driver, they can be advantageously used to anticipate an action such as a coupling or decoupling of the engine electric ME.

Current traffic information may, for example, be provided by a traffic information application, possibly remote searchable. This is for example information that is related to accidents, work and traffic jams, and that are likely to influence traffic on the path taken by a driver with his vehicle V. It will be understood that such information that can be known by the vehicle V sooner than its driver, they can be advantageously used to anticipate an action such as a coupling or decoupling of the electric motor ME.

A coupling proposal of the electric motor ME may have several purposes. Thus, it may be intended to recover electrical energy by braking (when the vehicle V is equipped for this purpose), when environmental information signal a need for slowing of the vehicle V. It may also be intended to increase the torque that is offered by the transmission chain when environmental information signal a need for acceleration of the vehicle V. Similarly, a proposal for decoupling the electric motor ME may have several purposes. Thus, it may be intended to avoid unnecessary use of the electric motor ME when environmental information signal a speed limitation and the current speed of the vehicle V is stabilized around this speed limit. It may also be intended to avoid unnecessary use of the electric motor ME when environmental information signal a substantially constant distance between the vehicle V considered and a vehicle in front of it and that the speed of the vehicle V is substantially constant for a few moments (for example several seconds). It will be understood that in these two examples of proposal, the electric motor ME is no longer wired by the vehicle V, and therefore no longer consumes unnecessarily fossil energy (fuel) by pure dissipation.

The invention offers several advantages, among which: a reduction in the state of the transmission chain, and thus a reduction in the driver's discomfort and an improvement in the overall approval of the passengers of the vehicle, an anticipation of the changes; state of the transmission chain, and thus a reduction in fuel consumption.

Claims (10)

REVENDICATIONS1. A method of assisting the coupling / decoupling of at least one machine (ME) to a transmission chain of a hybrid vehicle (V) flowing in an environment, characterized in that it consists in proposing a coupling / decoupling of said machine (ME) to said transmission chain according to information representative of said environment. 2. Method according to claim 1, characterized in that 1 o a coupling of said machine (ME), adapted to recover electrical energy by braking, in the presence of environmental information indicating a need for slowing down said vehicle. 3. Method according to one of claims 1 and 2, characterized in that it is proposed a coupling of said machine (ME), able to increase a torque offered by said transmission chain, in the presence of information of environment signaling a need for acceleration of said vehicle. 4. Method according to one of claims 1 to 3, characterized in that it consists in proposing the coupling / decoupling according to further information relating to said vehicle (V) and selected from a group 20 comprising at least one depression an accelerator pedal of said vehicle (V), a depression of a brake pedal of said vehicle (V), a running speed of said vehicle (V), a current inclination of said vehicle (V), and a constraint using said machine (ME) and / or a heat engine of said transmission chain. 25 5. Method according to one of claims 1 to 4, characterized in that said environment information is selected from a group comprising at least traffic lane signaling information, traffic zone type information, information anti-collision devices relating to a vehicle preceding said vehicle (V), traffic information and meteorological information. 6. Method according to one of claims 1 to 5, characterized in that said traffic lane signaling information is selected from a group comprising at least the indications of traffic signs, the color of a traffic light, and markings on the ground. 7. Method according to one of claims 1 to 6, characterized in that said anti-collision information is selected from a group comprising at least an estimated speed of the vehicle preceding said vehicle (V), a distance separating said vehicle (V) of a vehicle preceding it, and an estimated time before a collision with the vehicle preceding said vehicle (V). 8. A method according to claim 4 in combination with claims 6 and 7, characterized in that it is proposed a decoupling of said machine (ME) in the presence of environmental information indicating a speed limitation and a running speed of said vehicle (V) stabilized around said speed limitation and / or environmental information signaling a substantially constant distance between said vehicle (V) and a vehicle in front of it and a speed of said vehicle (V) substantially constant. 9. Device (D) for assisting the coupling / decoupling of at least one machine (ME) to a transmission chain of a hybrid vehicle (V) flowing in an environment, characterized in that it is arranged for 20 proposing a coupling / decoupling of said electric motor (ME) to said transmission chain as a function of information representative of said environment. 10. Hybrid vehicle (V) comprising a transmission chain comprising at least one machine (ME) and a heat engine (MT), characterized in that it further comprises a device (D) according to claim 9 .