Method and system for controlling a hybrid powertrain based on a torque gradient - Patents.com

Abstract

The invention relates to a system for controlling a hybrid powertrain of a motor vehicle, comprising a set of calculation means (1, 12, 13, 14, 15, 17, 18, 25) and a switch (24) configured to: determine an operating point and an overall consumption of the powertrain and a raw torque setpoint of the internal combustion engine; determine the gradient of an equivalence coefficient according to the consumption of the powertrain; determine the gradient of the torque at the crankshaft according to a target torque required at the wheels and the gear ratio; determine a minimum and a maximum value of the internal combustion engine torque gradient according to the gradient of the equivalence coefficient, the gradient of the torque at the crankshaft and a table; determine an optimal torque setpoint according to the raw torque setpoint and the minimum and the maximum value of the internal combustion engine torque gradient.

Description

[Technical field]

[0001] The present invention relates to the technical field of hybrid powertrain control.

[0002] Hybrid motor vehicles are generally equipped with an internal combustion engine and one or more electric motors. Such hybrid motor vehicles, like other motor vehicles, must be able to comply with pollution-control standards in each of the countries in which they are sold and must enable gains in performance and improved fuel consumption.

[0003] Hybrid motor vehicles may be equipped with various powertrains. Powertrains called "mild hybrids" are particularly known, in which an internal combustion engine is combined with an electric machine capable of operating as a motor or as a generator. A primary drive shaft is connected to the internal combustion engine crankshaft, for example by means of a belt-type elastic means. The primary drive shaft is associated with a gearbox so as to provide a number of possible transmission ratios between the rotational speed of the internal combustion engine and that of the primary drive shaft. The electric machine is then coupled to the internal combustion engine, and the ratio at which it drives the wheels cannot be varied independently of the ratio of the internal combustion engine.

[0004] Powertrains are also known in which the step-down gear ratio for the internal combustion engine and the step-down gear ratio for the electric machine are independent of each other. For example, document FR-A1-3022495 discloses an arrangement with an internal combustion engine and at least a first electric machine mounted at the end of a shaft.

[0005] Independent of hybridizing the vehicle powertrain, it is necessary to have a control method capable of managing the distribution of the vehicle's power between the various traction members. In other words, the driver's request for torque is distributed between the internal combustion engine and the electric machine(s), taking into full account the respective transmission ratios and any other possible constraints. These constraints include, among others: Consideration of "driver's wishes" based on the degree to which the throttle pedal is depressed Pollution Control Thermal comfort (heating inside the vehicle) · NVH (Noise, Vibration and Harshness) Management

[0006] This control method comprises a series of steps, hereinafter also referred to as the "energy management law", operating in two stages: the first stage is a stage of defining the optimization field according to the above-mentioned constraints, and the second stage is a stage of energy optimization linked to the overall consumption of the powertrain.

[0007] The optimization field consists in defining the range of possible torques for the internal combustion engine and the electric machine(s). The following example shows the optimization field for various constraints. For pollution control constraints, in case of cold weather operation with rapid heating of the pollution control catalytic converter, a time window of high torque may be imposed on the IC engine to allow for increased thermal losses. For vibration constraints, limits may be imposed on the gearbox ratio and the IC engine torque may be limited to a certain range that depends on the rotational speed. For vehicle interior heating constraints, a minimum torque may be imposed on the internal combustion engine to be achieved in order to rapidly increase the temperature of the coolant and thereby increase the temperature to which the vehicle interior heats up.

[0008] Since this field of optimization is generally not limited to a single choice of torque for each power source, the energy management method may therefore define an operating point / optimum distribution of torque or force between the traction members to optimize the overall consumption of the powertrain depending on the energy present in the battery and the driver's desire for torque at the wheels.

[0009] Since the optimization field is generally an open field depending on the type of optimization present in the energy management method, the optimal operating point can change very quickly depending on the physical parameters and energy manifestation of the traction members.

[0010] Consider an example of a linear model for the consumption of an internal combustion engine of the following type: TIFF2025515295000002.tif6170, where A_ENG and B_ENG are coefficients that depend on the rotation speed of the internal combustion engine, T_ENG is the torque required at the output from the internal combustion engine.

[0011] Also consider an example of a second-order polynomial model of the consumption of an electric motor, of the following type: TIFF2025515295000003.tif6170, where A_ME, B_ME and C_ME are coefficients that depend on the rotational speed of the electric motor, T_ME is the torque required at the output from the electric motor.

[0012] In some operating scenarios, it may happen that the rotational speed of the electric machine and the rotational speed of the internal combustion engine are out of phase (e.g. due to lash in the gearbox, in the flywheel, or due to elasticity of the belt connecting the internal combustion engine crankshaft and the output shaft of the electric machine) and that some physical mechanisms cause rotational speed fluctuations, for example, valve lift management in a variable lift valve leads to rotational speed fluctuations of the internal combustion engine at some operating points.

[0013] The phase difference between the electrical model (equation 2) and the thermal model (equation 1) means that at a given instant t, the internal combustion engine has a lower consumption than the electric machine consumption. This phase difference therefore causes the consumption optimization to issue a higher internal combustion engine torque target than the electric motor torque target.

[0014] As a result, at a later time instant t+δt, it is the electric motor that exhibits the lower consumption due to the phase difference between the electrical model and the thermal model. The consumption optimization then issues an internal combustion engine torque target that is not as high as the torque target of the electric motor.

[0015] The situation represented at the instant t and the situation represented at the instant t+δt may follow each other, resulting in torque fluctuations, so that the phase difference between the consumption model for the internal combustion engine and the consumption model for the electric motor increases, tending to keep the optimal torque set point fluctuations even more dynamic.

[0016] Therefore, the operating point becomes unstable in some situations due to the self-sustaining fluctuating behavior of the governing law.

[0017] The technical problem to be addressed is therefore how to suppress the fluctuations and instabilities of the hybrid powertrain associated with the manner in which the optimal operating point is determined by energy management and at the same time adapt to the field of optimization and the normal evolution of this point. Summary of the Invention

[0018] The present invention relates to a method for controlling an automotive vehicle hybrid powertrain comprising an internal combustion engine and at least one electric machine associated with a battery, the method comprising the following steps: an energy control method is used to determine a raw torque setpoint for the internal combustion engine depending on an overall consumption of the powertrain, a consumption of the internal combustion engine, and a consumption of at least one electric machine; an equivalence factor and a slope of the equivalence factor are determined as a function of the current energy present in the battery and the target battery energy; A crankshaft torque is determined as a function of the target torque required at the wheels, obtained from the energy management method, and the reduction gearing, and a crankshaft torque gradient is determined. the internal combustion engine torque gradient minimum value and the internal combustion engine torque gradient maximum value are determined using a parameterizable table that is dependent on the gradient of the equivalence coefficient and the filtered crankshaft target torque gradient, respectively; the optimal engine torque is determined as a function of the engine raw torque set point by limiting its change dynamics as a function of the engine torque gradient minimum and the engine torque gradient maximum; The present invention relates to a method comprising the steps of:

[0019] 2. The method of claim 1, further comprising the step of first order filtering the crankshaft torque gradient in response to a time constant stored in a memory.

[0020] The method comprises the following steps: It is determined that if the predefined minimum value for the optimum internal combustion engine torque is higher than the optimum internal combustion engine torque value, the first logical value adopts a first value, and if this is not the case, the first logical value adopts a second value. It is determined that if the predefined maximum value for the optimum internal combustion engine torque is lower than the optimum internal combustion engine torque value, the second logical value adopts the first value, and if this is not the case, the second logical value adopts the second value. the selected value is determined as a function of a logical OR operation performed between the first logical value and the second logical value; For the determination of the optimum engine torque, a first set of predefined values ​​comprising an engine torque gradient minimum value and an engine torque gradient maximum value is transmitted as a final minimum engine torque gradient and a final maximum engine torque gradient if the selection value adopts a first value, and a second set of predefined values ​​comprising a default engine torque gradient minimum value and a default engine torque gradient maximum value is transmitted if the selection value adopts a second value. may include.

[0021] The default internal combustion engine torque gradient minimum value may adopt a value lower than the internal combustion engine torque gradient minimum value, and the default internal combustion engine torque gradient maximum value may adopt a value higher than the internal combustion engine torque gradient maximum value.

[0022] The present invention also provides a system for controlling an automotive vehicle hybrid powertrain, comprising a first computing means configured to execute an energy management strategy to determine an internal combustion engine raw torque set point, the control system comprising: second and third computing means configured to determine a slope of an equivalence factor between the current energy present in the battery and the target battery energy; a fourth calculation means and a fifth calculation means configured to determine a crankshaft torque gradient as a function of a required target torque of the wheels and a reduction gear ratio; a sixth calculation means and a seventh calculation means configured to determine an internal combustion engine torque gradient maximum value and an internal combustion engine torque gradient minimum value as a function of the gradient of the equivalence coefficient, the crankshaft torque gradient, and a table stored in a memory of the respective calculation means; and an eighth calculation means configured to determine an optimal torque set point as a function of the raw torque set point and the internal combustion engine torque gradient minimum value and the internal combustion engine torque gradient maximum value so as to correct the dynamics of its change. The present invention relates to a system comprising:

[0023] The system may comprise filtering means configured to perform first order filtering of the crankshaft torque gradient transmitted to the sixth and seventh calculation means in response to a time constant stored in the memory.

[0024] The system includes a first memory containing a default engine torque gradient minimum value and a default engine torque gradient maximum value, a second memory containing an optimum engine torque minimum value and an optimum engine torque maximum value, and a first comparison means configured to issue a first value if the current optimum engine torque value is higher than the optimum engine torque minimum value, and to issue a second value otherwise. second comparison means configured to issue a first value if the current optimum engine torque value is lower than the maximum optimum engine torque value, and to issue a second value otherwise; a Boolean operator configured to apply an OR truth table to the values ​​received from the first comparing means and the second comparing means; a switch configured to transmit, to an eighth computing means, the internal combustion engine torque gradient minimum value and the internal combustion engine torque gradient maximum value if the second value is received from the Boolean operator, and to transmit, to an eighth computing means, a default internal combustion engine torque gradient minimum value and a default internal combustion engine torque gradient maximum value if the first value is received from the Boolean operator; It may comprise:

[0025] Other objects, features and advantages of the present invention will become apparent on reading the following description, given purely by way of non-limiting example and with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0026] [Figure 1] FIG. 2 illustrates the main steps of the control method according to the invention. [Diagram 2] FIG. 2 shows the main elements of a control system according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The method for controlling a hybrid powertrain of a motor vehicle has the objective of suppressing and reducing the dynamics of changes of the optimal operating point of the energy management method and at the same time ensuring compliance with the field of optimization at every moment as well as the expected dynamics of changes in the battery energy conditions and current force / torque at the wheel demands. The hybrid powertrain comprises an internal combustion engine and at least one electric machine associated with a battery.

[0028] Define the following variables: - WHL_TQ_TG is the target torque required at the wheels, which is developed based on the driver's demand and third party functions that have an influence on its development (speed regulator, autonomous driving, etc.). - ENG_TQ_OPT_MIN is the optimal IC engine torque minimum resulting from upstream functions in the energy management law that handle trade-offs between constraints associated with drivability, thermal comfort, battery management, etc. - ENG_TQ_OPT_MAX is the maximum optimal engine torque resulting from upstream functions in the energy management law that handle the trade-offs between constraints associated with drivability, thermal comfort, battery management, etc. ENG_TQ_OPT_RAW is the internal combustion engine raw torque setpoint derived from the energy management method, this is the torque at which it is desired to reduce its emission dynamics. FAC_EQ is the electricity consumption equivalent factor based on the equivalent consumption minimization strategy. - ENG_TQ_OPT is the internal combustion engine optimum torque, which is then fed into a function for creating the powertrain torque setpoint. - EGY_CRT is the current energy present in the battery, this is information sent directly by the function that handles the monitoring of the battery. - EGY_TGT is the target battery energy, calculated within the energy management function based on a parameterized nominal target and based on specific energy requirements (activation of a charging mode via the driver interface, increased energy to perform specific pollution control functions, etc.).

[0029] The equivalent coefficient FAC_EQ is expressed as follows: This allows the determination of TIFF2025515295000004.tif11170. TIFF2025515295000005.tif6170

[0030] In other words, the value FAC_EQ represents an equivalence factor expressing the equivalence between the consumption of at least one electric motor and the consumption of the internal combustion engine, this parameter being dynamically changing mainly depending on the level of energy present in the battery. This factor is greater than 1.

[0031] The equivalence factor FAC_EQ is typically constructed based on the current energy present in the battery and the energy target. To determine the value of the equivalence factor FAC_EQ, a proportional gain (EGY_FAC_GAIN) is applied to the difference between the current energy present in the battery and the energy target, and then a neutral value (EGY_FAC_NEUTRAL) is added, which implies that electrical energy and thermal energy are of equal value.

[0032] The proportional gain value and the neutral value are generally parameterized iteratively.

[0033] Multiple execution cycles are performed with multiple set equivalence factor values, allowing for: - Finding a neutral value that ensures that the electrical energy changes over the course of the cycle but is the same at the start of the cycle as it is at the end of the cycle. - To find values, it is known how to estimate the gain or electrical energy consumption per kilometer depending on the energy at the beginning of the cycle, the energy at the end of the cycle and the distance covered.

[0034] The proportional gain is therefore parameterized in such a way as to obtain the desired charge / discharge depending on the desired dynamics of change, which is generally a compromise between various performance aspects (availability of electric mode, unlimited utilization of battery energy to optimize consumption, NVH with high levels of recharging to approach the target, etc.).

[0035] FIG. 1 shows the main steps of the control method according to the invention.

[0036] During the course of a first step 1, an energy management method is used to determine the operating point of the hybrid powertrain, i.e. the internal combustion engine raw torque setpoint ENG_TQ_OPT_RAW, as a function of the overall consumption of the powertrain via an analytical solution of an equation making it possible to define an operating point with the lowest possible consumption. TIFF2025515295000006.tif10170

[0037] During the second step 2 process, an equalization coefficient FAC_EQ is determined as a function of the current energy present in the battery and the target battery energy.

[0038] FAC_EQ=(EGY_TGT-EGY_CRT)*EGY_FAC_GAIN+EGY_FAC_NEUT Where: EGY_FAC_GAIN is the parameterized proportional gain EGY_FAC_NEUT is the equivalence factor neutral value

[0039] The variation of the equivalent coefficient FAC_EQ over a predefined duration (e.g., 1 second) is then quantified. To do this, the current value of the equivalent coefficient FAC_EQ is subtracted from the value that the equivalent coefficient FAC_EQ had in the previous time step, and the result is divided by this same time step. This then results in an equivalent coefficient slope FAC_EQ_GRD that makes it possible to see how the equivalent coefficient FAC_EQ is changing over a predefined duration.

[0040] During the course of the third step 3, the target torque WHL_TQ_TG required at the wheels and the reduction gearing ENG_RAT are obtained from the energy management method. The variations in the crankshaft torque and therefore in the internal combustion engine torque are then quantified. To do this, the target torque WHL_TQ_TG required at the wheels is divided by the reduction gearing ENG_RAT between the internal combustion engine and the wheels. This then results in the crankshaft torque CRK_TQ_TG. The gradient of the crankshaft torque CRK_TQ_TG is determined in a similar manner to the way in which the equivalent coefficient gradient FAC_EQ_GRD is calculated. More specifically, the current value of the crankshaft torque CRK_TQ_TG is subtracted from the value that the crankshaft torque CRK_TQ_TG had in the previous time step and the result is divided in this same time step. This in turn produces a crankshaft torque gradient CRK_TQ_TG_GRD that characterizes the change in the target wheel torque set point at the crankshaft over a predetermined duration.

[0041] Since the crankshaft torque gradient CRK_TQ_TG_GRD may be affected by noise in the change of the required target torque WHL_TQ_TG at the wheels, a first order filter is introduced with a time constant TAU ​​which may be adjusted to obtain a filtered crankshaft target torque gradient CRK_TQ_TG_GRD_FIL.

[0042] During the course of the fourth step 4, the engine torque gradient minimum value CRK_TQ_OPT_GRD_MIN_TABLE and the engine torque gradient maximum value CRK_TQ_OPT_GRD_MAX_TABLE are determined by the parameterizable two-dimensional tables TABLE_2D_GRD_POS_MIN and TABLE_2D_GRD_POS_MAX, respectively, each of which depends on the equivalent coefficient gradient FAC_EQ_GRD and the filtered crankshaft target torque gradient CRK_TQ_TG_GRD_FIL.

[0043] The engine torque gradient minimum value CRK_TQ_OPT_GRD_MIN_TABLE and the engine torque gradient maximum value CRK_TQ_OPT_GRD_MAX_TABLE represent normal changes in the engine optimum torque. What is meant by "normal changes in the engine optimum torque" is an increase or decrease in torque that can naturally be observed when the filtered crankshaft torque gradient value CRK_TQ_TG_GRD_FIL and the equivalent coefficient gradient FAC_EQ_GRD are changed. The filtered crankshaft torque gradient value CRK_TQ_TG_GRD_FIL corresponds to the target torque set point WHL_TQ_TG required at the wheels and thus to the driver's wishes. - If the driver's wishes, expressed in terms of the crankshaft values, increase by a value X (in Nm / s), the internal combustion engine optimum torque can be expected to increase by a value Y (in Nm / s), which is slightly more than the value X and is parameterized in the first table TABLE_2D_GRD_POS_MAX. If the equivalence factor increases, the internal combustion engine optimum torque can be expected to increase by an amount of torque of value Z (in Nm / s) parameterized in the first table TABLE_2D_GRD_POS_MAX.

[0044] During the course of a fifth step 5, it is determined whether the internal combustion engine optimum torque minimum value ENG_TQ_OPT_MIN is higher than the internal combustion engine optimum torque value ENG_TQ_OPT. If the internal combustion engine optimum torque minimum value ENG_TQ_OPT_MIN is higher than the internal combustion engine optimum torque value ENG_TQ_OPT, the first logical value is determined to be equal to a first value. If the internal combustion engine optimum torque minimum value ENG_TQ_OPT_MIN is not higher than the internal combustion engine optimum torque value ENG_TQ_OPT, the first logical value is determined to be equal to a second value.

[0045] Also, it is determined whether the internal combustion engine optimum torque maximum value ENG_TQ_OPT_MAX is lower than the internal combustion engine optimum torque value ENG_TQ_OPT. If the internal combustion engine optimum torque maximum value ENG_TQ_OPT_MAX is lower than the internal combustion engine optimum torque value ENG_TQ_OPT, it is determined that the second logical value is equal to the first value. If the internal combustion engine optimum torque maximum value ENG_TQ_OPT_MAX is not lower than the internal combustion engine optimum torque value ENG_TQ_OPT, it is determined that the second logical value is equal to the second value.

[0046] During the course of the sixth step 6, the selection value is determined depending on a logical OR operation carried out between the first logical value and the second logical value. In other words, the selection value adopts the first value if at least one of the first logical value and the second logical value is equal to the first value. If at least one of the first logical value and the second logical value is not equal to the first value, the selection value adopts the second value.

[0047] During the course of the seventh step 7, the final engine torque minimum gradient CRK_TQ_OPT_GRD_MIN and the final engine torque maximum gradient CRK_TQ_OPT_GRD_MAX, which are subsequently used to dampen and reduce the dynamics of the change in the engine optimal torque, are selected from among a first set of values ​​comprising the engine torque gradient minimum values ​​CRK_TQ_OPT_GRD_MIN_TABLE and the engine torque gradient maximum values ​​CRK_TQ_OPT_GRD_MAX_TABLE, and a second set of values ​​comprising the default engine torque gradient minimum values ​​CRK_TQ_OPT_GRD_MIN_DFT and the default engine torque gradient maximum values ​​CRK_TQ_OPT_GRD_MAX_DFT, depending on the selection value.

[0048] More specifically, the first set of values ​​is selected if the selected value adopts a second value, and the second set of values ​​is selected if the selected value adopts the first value.

[0049] This selection of the gradients makes it possible to select default gradients CRK_TQ_OPT_GRD_MIN_DFT and CRK_TQ_OPT_GRD_MAX_DFT which enable the engine optimum torque ENG_TQ_OPT to be quickly and even immediately returned within the field of optimization in cases where the engine optimum torque value ENG_TQ_OPT, the dynamics of whose change is reduced, is outside the field of optimization defined by the rapid changes of the engine optimum torque minimum value ENG_TQ_OPT_MIN and the engine optimum torque maximum value ENG_TQ_OPT_MAX.

[0050] The default slopes CRK_TQ_OPT_GRD_MIN_DFT and CRK_TQ_OPT_GRD_MAX_DFT generally have values ​​lower / higher, respectively, than the nominal slopes taken from the two-dimensional table.

[0051] Since the end points depend on various constraints (pollution control, vehicle interior thermal comfort, etc.), one of the end points is very quickly, and even immediately, if at the time of activation of the function (for example, a clearly high desire for vehicle interior heating), the internal combustion engine optimum torque ENG_TQ_OPT is at the internal combustion engine optimum torque minimum value ENG_TQ_OPT_MIN and this value increases significantly and quickly in order to provide a torque for vehicle interior thermal comfort which requires the internal combustion engine to be heated up quickly by imposing a high minimum torque on the internal combustion engine, it is absolutely essential to allow the internal combustion engine optimum torque ENG_TQ_OPT to adapt to this new minimum end point, so that at the moment of increase the internal combustion engine optimum torque ENG_TQ_OPT is below the new internal combustion engine optimum torque minimum value ENG_TQ_OPT_MIN and therefore the default gradient selected allows a quick, and even instantaneous, increase of the internal combustion engine optimum torque ENG_TQ_OPT towards the internal combustion engine optimum torque minimum value ENG_TQ_OPT_MIN despite there being no change in the driver's wishes or the equivalence factor.

[0052] During the course of the eighth step 8, the engine optimal torque ENG_TQ_OPT is determined according to the engine raw torque set point ENG_TQ_OPT_RAW derived from the energy management method while limiting its dynamics of change according to the final engine torque minimum gradient CRK_TQ_OPT_GRD_MIN and the final engine torque maximum gradient CRK_TQ_OPT_GRD_MAX, according to the following logic: ENG_TQ_OPT(t) =Max(Min(ENG_TQ_OPT_RAW(t);ENG_TQ_OPT(t-dt)+CRK_TQ_OPT_GRD_MAX*dt);ENG_TQ_OPT(t-dt)+CRK_TQ_OPT_GRD_MIN*dt)

[0053] where t is the current calculation step and dt is the duration between two successive calculation steps in the strategy.

[0054] This determination therefore makes it possible to obtain an engine optimum torque ENG_TQ_OPT whose dynamics of change are potentially lower than those of the engine raw torque setpoint ENG_TQ_OPT_RAW.

[0055] Thus, the dynamics of change of the internal combustion engine optimal torque and of the optimal operating point derived from the energy management method are suppressed and reduced, while at the same time maintaining the dynamics of change that would normally be expected depending on the parameters that have a direct influence on their selection (torque at the wheels and equivalent coefficients), ensuring that the optimization field is respected at every moment.

[0056] The control method thus makes it possible to counteract self-induced fluctuation phenomena and at the same time to dampen the dynamics of the change of the operating point.

[0057] The present invention also relates to a system for controlling an automotive vehicle hybrid powertrain, as shown in FIG.

[0058] The control system 10 comprises first calculation means 11 configured to execute an energy management method to determine the operating point of the hybrid powertrain, i.e. the internal combustion engine raw torque set point ENG_TQ_OPT_RAW, as a function of the overall consumption of the powertrain, via an analytical solution of an equation making it possible to define an operating point with the lowest possible consumption.

[0059] Second calculation means 12 are configured to determine an equivalence factor FAC_EQ as a function of the current energy present in the battery and the target battery energy.

[0060] A third calculation means 13 determines an equalization coefficient gradient FAC_EQ_GRD depending on the equalization coefficient FAC_EQ at the current instant, the stored values ​​of the equalization coefficient FAC_EQ at the preceding instant, and the duration between the current instant and the preceding instant. At its first occurrence, the gradient is initialized to its current value.

[0061] A fourth calculation means 14 determines the crankshaft torque CRK_TQ_TG as a function of the target torque WHL_TQ_TG required at the wheels and the reduction gear ratio ENG_RAT.

[0062] A fifth calculation means 15 determines the crankshaft torque gradient CRK_TQ_TG_GRD as a function of the crankshaft torque CRK_TQ_TG at the current moment, the stored values ​​in the memory of the crankshaft torque CRK_TQ_TG at the preceding moment, and the duration between the current moment and the preceding moment. At its first occurrence, the gradient is initialized to a predefined default value.

[0063] The filter processing means 16 performs a first-order filter process on the crankshaft torque gradient CRK_TQ_TG_GRD based on the time constant TAU.

[0064] Sixth calculation means 17, associated with a memory containing the first table TABLE_2D_GRD_POS_MAX, are configured to determine the internal combustion engine torque gradient maximum value CRK_TQ_OPT_GRD_MAX_TABLE as a function of the equivalence coefficient gradient FAC_EQ_GRD and the crankshaft torque gradient CRK_TQ_TG_GRD_FIL.

[0065] Seventh calculation means 18, associated with a memory containing the table TABLE_2D_GRD_POS_MIN, are configured to determine the internal combustion engine torque gradient minimum value CRK_TQ_OPT_GRD_MIN_TABLE as a function of the equivalence coefficient gradient FAC_EQ_GRD and the crankshaft torque gradient CRK_TQ_TG_GRD_FIL.

[0066] A first memory 19 contains a default engine torque gradient minimum value CRK_TQ_OPT_GRD_MIN_DFT and a default engine torque gradient maximum value CRK_TQ_OPT_GRD_MAX_DFT.

[0067] A second memory 20 contains an internal combustion engine optimum torque minimum value ENG_TQ_OPT_MIN and an internal combustion engine optimum torque maximum value ENG_TQ_OPT_MAX.

[0068] The first comparison means 21 is configured to determine whether the current engine optimum torque value ENG_TQ_OPT is higher than the engine optimum torque minimum value ENG_TQ_OPT_MIN and to emit a first value if the current engine optimum torque value ENG_TQ_OPT is higher than the engine optimum torque minimum value ENG_TQ_OPT_MIN or to emit a second value if this is not the case.

[0069] The second comparison means 22 is configured to determine whether the current engine optimum torque value ENG_TQ_OPT is lower than the maximum engine optimum torque value ENG_TQ_OPT_MAX and to emit a first value if the current engine optimum torque value ENG_TQ_OPT is lower than the maximum engine optimum torque value ENG_TQ_OPT_MAX and to emit a second value if this is not the case.

[0070] A Boolean operator 23 is configured to apply an OR truth table to the values ​​received from the first comparing means 21 and the second comparing means 22 .

[0071] The switch 24 enables selection of the engine torque gradient minimum value CRK_TQ_OPT_GRD_MIN_TABLE and the engine torque gradient maximum value CRK_TQ_OPT_GRD_MAX_TABLE when a second value is received from the Boolean operator 23, and selection of the default engine torque gradient minimum value CRK_TQ_OPT_GRD_MIN_DFT and the default engine torque gradient maximum value CRK_TQ_OPT_GRD_MAX_DFT when a first value is received from the Boolean operator 23.

[0072] An eighth calculation means 25 is configured to determine the optimal torque set point ENG_TQ_OPT as a function of the raw torque set point ENG_TQ_OPT_RAW and the value received from the switch 24 according to the following logic: ENG_TQ_OPT(t) =Max(Min(ENG_TQ_OPT_RAW(t);ENG_TQ_OPT(t-dt)+CRK_TQ_OPT_GRD_MAX*dt);ENG_TQ_OPT(t-dt)+CRK_TQ_OPT_GRD_MIN*dt)

[0073] where t is the current calculation step and dt is the duration between two successive calculations in the strategy.

[0074] It will be appreciated that the various memories may also be separate memory spaces comprised within one and the same physical memory.

Claims

1. A method for controlling an automated vehicle hybrid powertrain comprising an internal combustion engine and at least one electromechanical device associated with a battery, comprising the following steps, namely: A step in which an energy management method is used to determine an optimal raw torque setpoint for an internal combustion engine in accordance with the overall consumption of the powertrain, the consumption of the internal combustion engine, and the consumption of the at least one electromechanical device, A step in which the equivalent coefficient and the gradient of the equivalent coefficient are determined according to the current energy present in the battery and the target battery energy, The crankshaft torque is determined according to the target torque required at the wheel and the reduction gearing, obtained from the energy management method, and the crankshaft torque gradient is determined in this step. A step in which the minimum and maximum values ​​of the internal combustion engine torque gradient are determined using a parameterizable table, where the gradient of the equivalent coefficient and the filtered crankshaft target torque gradient, respectively, The optimal internal combustion engine torque is determined according to the internal combustion engine torque setting point by limiting the dynamics of its change according to the minimum value and maximum value of the internal combustion engine torque gradient. Methods that include...

2. The control method according to claim 1, further comprising the step of performing a primary filter on the crankshaft torque gradient according to a time constant stored in memory.

3. The following steps, namely, The step of determining whether the first logical value adopts the first value if the predetermined minimum value for the optimal internal combustion engine torque is higher than the value of the optimal internal combustion engine torque, and whether the first logical value adopts the second value otherwise. The step of determining whether the second logical value adopts the first value if the predefined maximum value for the optimal internal combustion engine torque is lower than the value of the optimal internal combustion engine torque, and whether the second logical value adopts the second value otherwise. A step in which the selected value is determined according to a logical OR operation performed between the first logical value and the second logical value, For the determination of the optimal internal combustion engine torque, if the selected value adopts the second value, a first set including the minimum internal combustion engine torque gradient and the maximum internal combustion engine torque gradient is transmitted as the final minimum internal combustion engine torque gradient and the final maximum internal combustion engine torque gradient; if the selected value adopts the first value, a second set of predefined values ​​including the default minimum internal combustion engine torque gradient and the default maximum internal combustion engine torque gradient is transmitted. A control method according to claim 1 or 2, including the following:

4. The control method according to claim 1 or 2, wherein the default minimum torque gradient of the internal combustion engine is lower than the minimum torque gradient of the internal combustion engine, and the default maximum torque gradient of the internal combustion engine is higher than the maximum torque gradient of the internal combustion engine.

5. A control system for controlling an automatic vehicle hybrid powertrain, comprising a first calculation means (11) configured to perform an energy management method to determine an internal combustion engine torque setpoint, wherein the control system A second calculation means (12) and a third calculation means (13) are configured to determine the gradient of the equivalent coefficient according to the power consumption of the powertrain, A fourth calculation means (14) and a fifth calculation means (15) configured to determine the crankshaft torque gradient according to the required target torque and reduction gear ratio of the wheel; a sixth calculation means (17) and a seventh calculation means (18) configured to determine the maximum and minimum values ​​of the internal combustion engine torque gradient according to the gradient of the equivalent coefficient, the crankshaft torque gradient, and a table stored in the memory of each of the calculation means; and an eighth calculation means (25) configured to determine the optimal torque setting point according to the raw torque setting point, the minimum and maximum values ​​of the internal combustion engine torque gradient, in order to correct the dynamics of its change. A control system characterized by comprising the following features.

6. The control system according to claim 5, further comprising a filtering means (16) configured to perform primary filtering of the crankshaft torque gradient transmitted to the sixth calculation means (17) and the seventh calculation means (18) according to a time constant stored in memory.

7. A first memory (19) containing the default minimum internal combustion engine torque gradient and the default maximum internal combustion engine torque gradient; a second memory (20) containing the optimal minimum internal combustion engine torque and the optimal maximum internal combustion engine torque; and a first comparison means (21) configured to output a first value if the current optimal internal combustion engine torque value is higher than the optimal minimum internal combustion engine torque, and a second value otherwise. A second comparison means (22) is configured to emit a first value if the current optimal internal combustion engine torque value is lower than the maximum optimal internal combustion engine torque value, and a second value otherwise. A Boolean operator (23) configured to apply an OR truth table to the values ​​received from the first comparison means (21) and the second comparison means (22), A switch (24) is configured to transmit the minimum and maximum values ​​of the internal combustion engine torque gradient to the eighth calculation means (25) when a second value is received from the Boolean operator (23), and to transmit the default minimum and maximum values ​​of the internal combustion engine torque gradient to the eighth calculation means (25) when a first value is received from the Boolean operator (23). The control system according to claim 5 or 6, comprising:

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