WO2012101368A1

WO2012101368A1 - Method of determining the economical nature of the driving of a motor vehicle

Info

Publication number: WO2012101368A1
Application number: PCT/FR2012/050143
Authority: WO
Inventors: Mathias GALVIN; Yves Francais
Original assignee: Peugeot Citroen Automobiles Sa
Priority date: 2011-01-26
Filing date: 2012-01-23
Publication date: 2012-08-02
Also published as: FR2970777A1; FR2970777B1

Abstract

The invention relates to a method of determining the economical nature of the driving of a motor vehicle by a driver, the method comprising a measurement step during which sensors measure parameters linked to the fuel consumption of the engine, and a step of displaying an item of information regarding the economical nature of the driving. According to the invention, the information item displayed is a deviation in fuel consumption between the consumption related to the driver's driving determined on the basis of the measured parameters, and the consumption related to a reference driving determined on the basis of reference data previously integrated into the vehicle.

Description

METHOD FOR DETERMINING AN ECONOMIC CHARACTER OF THE DRIVING OF A MOTOR VEHICLE

[001] The invention relates to a method for determining an economic character of the driving of a motor vehicle by a driver.

[002] A vehicle is known comprising a system allowing the driver to have information on the economic nature of his driving. However the information given is a graphic representation of an icon whose representation varies according to the importance of the consumption.

[003] Thus, the information does not allow the driver to know what potential fuel consumption gain he can estimate by modifying his driving.

[004] The invention aims to solve this disadvantage. The invention thus relates to a method for determining the economic nature of driving a motor vehicle by a driver, the method comprising a step in which sensors measure parameters related to fuel consumption of the engine, and a step of displaying information on the economic nature of the pipe, characterized in that the information displayed is a difference in fuel consumption between, on the one hand, the consumption related to the driving of the driver determined from measured parameters, and, on the other hand, the consumption linked to a reference pipe determined from reference data previously integrated into the vehicle.

[005] According to a first variant of the method, one of the information displayed during the display step is a difference in fuel consumption related to the anticipation of the braking phases by the driver.

[006] According to a first feature of the first variant, during the display step, the difference in fuel consumption related to the anticipation of the braking phases is determined from the difference between, on the one hand, a braking force applied by the driver, and, on the other hand, a reference braking force previously integrated into the vehicle.

[007] According to a first preference, the value of the reference braking force used for displaying the difference in fuel consumption related to the anticipation of the braking phases depends on the inclination of the vehicle.

[008] According to a second preference, the braking force used for displaying the difference in fuel consumption related to the anticipation of the braking phases is determined from the measurement of the pressure of a master cylinder. a vehicle brake, and the reference braking force corresponds to a reference value of the pressure of the master cylinder previously integrated into the vehicle.

[009] According to a second feature of the first variant, the relative consumption corresponding to the anticipation of the braking phases displayed during the display step is given by the formula

AConso _Frem = (P - P _ref ) x KCP x (O _wheel x CSW

Where P is the measured value of the pressure of the master cylinder (in bar);

[001 1] P _ref is the reference value of the pressure of the master cylinder (in bar);

KCP is a constant brake system for associating a pressure of the master cylinder and a braking torque at a wheel of the vehicle;

G is the angular speed of rotation of a wheel (in rad.s ^"1 ), and

CSW is a constant equal to the Willans specific consumption (in g / kW.h) identified in a nominal engine load area from a map previously integrated into the vehicle giving the engine consumption according to its charge and its scheme.

According to a second variant, one of the information displayed during the method display step is a deviation of the fuel consumption related to the change of gear ratios by the driver.

According to a first feature of the second variant, during the display step, the difference in fuel consumption due to changes in gear ratios is determined from the difference between, on the one hand, , the engine speed, and, on the other hand, a reference engine speed depending on the reference gear ratio and the vehicle speed.

According to a first preference, the value of the reference engine speed used to display the difference in fuel consumption related to changes in speed reports depends on the inclination of the vehicle.

According to a second preference, the engine speed used to display the difference in fuel consumption related to changes in speed ratios is determined from the measurement of the speed of rotation of the shaft of the engine. motor, and the reference engine speed corresponds to a reference value of the rotational speed of the motor shaft.

According to a second feature of the second variant, the relative consumption corresponding to the change in the speed ratios displayed during the display step is given by the formula AConso _Report = x [N - N _ref ) x CSW

Where PMW is a constant equal to the average pressure of Willans (in bar);

Cyl is the value of the displacement of the engine (in I);

N is the value of the engine speed (in rpm ^"1 );

N _ref is the reference value of the engine speed (in rpm ^"1 ), and

According to a third variant, one of the information displayed during the display step of the method is a deviation of the consumption related to the load of the engine during an acceleration phase.

According to a first feature of the third variant, during the display step, the difference in fuel consumption related to the engine load during the acceleration phase is determined from the difference between, on the one hand, the specific Willans specific consumption of the engine, and, on the other hand, the reference specific Willans consumption previously incorporated into the vehicle.

According to one preference, the actual Willans specific consumption of the engine used for displaying the difference in fuel consumption related to the engine load during the acceleration phase is determined using a map previously integrated into the vehicle. giving the consumption of the engine according to its load and its regime, the specific consumption of Willans (CSW) being a constant identified from this mapping.

According to a second feature of the third variant, the relative consumption corresponding to the engine load during the acceleration phase displayed during the display step is given by the formula

AConso _Acceleration = ^Cmot ^ ^X * ^' x { _Actual CSW - CSW) Where Cmot is the actual motor torque (in Nm);

N is the value of the engine speed (in rpm ^"1 );

[0031] CSWreeiie is the specific consumption of the engine determined from its speed and its load; and

CSW is a constant equal to the Willans specific consumption (in g / kW.h). According to a fourth variant, one of the information displayed during the step of displaying the method is a deviation of the consumption related to the speed of the vehicle.

According to a first feature of the fourth variant, during the display step, the difference in fuel consumption related to the speed of the vehicle is determined from the difference between the speed of the vehicle and a reference vehicle speed previously integrated into the vehicle.

According to a second feature of the fourth variant, the relative consumption corresponding to the speed of the vehicle displayed during the display step is given by the formula

AConso _Speed = (f ₀ {v - V _ref ) + ² - Vl _f ) + f ₂ (v ³ - V _r ³ _ef )) x CSW

Where f ₀ is the first factor of the road law of the vehicle;

[0037] f-ι is the second factor of the road law of the vehicle;

F ₂ is the third factor of the road law of the vehicle;

V is the value of the speed of the vehicle;

[0040] V _ref is the value of the reference vehicle speed; and

CSW is a constant equal to the specific consumption of Willans (in g / kW.h).

According to a second aspect, the present invention also relates to a vehicle comprising a motor, sensors measuring parameters related to the fuel consumption of the engine, and a system for determining an economic nature of driving the vehicle by a conductor, characterized in that the system is adapted to compare the consumption related to the conduct of the driver determined from the parameters measured by the sensors, and that related to a reference pipe determined from previously integrated reference data, and to display the consumption gap.

Thus, the driver is informed of the difference in fuel consumption with respect to a reference conductor, and may be prompted to correct his driving behavior.

Other features and advantages of the invention will become apparent from the description which is given below, for information only and not limiting.

The invention proposes a motor vehicle comprising a motor, and sensors measuring parameters related to the fuel consumption of the engine. The vehicle also includes a screen for displaying information, or is connected to such an embedded screen.

According to the invention, the vehicle comprises a system for determining the economic nature of driving the vehicle. This system is suitable for comparing the consumption related to the conduct of the driver determined from the parameters measured by the sensors, and that related to a reference pipe determined from reference data previously incorporated into the vehicle, and to display the consumption difference at the screen.

The system for determining the economic nature of driving the vehicle makes it possible to implement a method for determining an economic nature of driving a motor vehicle by a driver. This method comprises a measurement step in which the sensors measure the parameters related to the fuel consumption, and a display step in which information on the economic nature of the pipe is displayed. According to the invention, the information displayed is a difference in fuel consumption between, on the one hand, the consumption related to the conduct of the driver determined from the parameters measured by the sensors, and, on the other hand, the consumption linked to a reference pipe determined from reference data previously integrated into the vehicle.

This relative consumption can be an instantaneous consumption value and / or a cumulated consumption value over time, the choice of the type of display that can be achieved by the driver via an interface. Similarly, the relative consumption value can be given in liter, liter per 100 km, gram C0 ₂ per km, etc., always with the possibility for the driver to choose the display unit.

In the present embodiment, to best assist the driver in reducing fuel consumption, it is divided into various positions which, in this case, are related to a specific behavior. Thus the driver can know what is his least economic behavior.

In the present embodiment, these consumption stations are four in number, and include, the anticipation of the braking phases, the change of speed ratios, the engine load in acceleration phase and the speed of the vehicle. For this purpose, the sensors comprise a first sensor for measuring the pressure of a master cylinder of a brake, a second sensor for measuring the rotational speed of the motor shaft, a third sensor for measuring the torque. motor, a fourth sensor for measuring the speed of the vehicle and the speed of rotation of a wheel of the vehicle, a fifth sensor for measuring the inclination of the vehicle (from front to rear) and therefore the of the road and a sixth sensor measuring the depression of the accelerator pedal. A first information displayed is a difference in fuel consumption related to the anticipation of the braking phases by the driver. This difference in consumption is determined from the difference between, on the one hand, a braking force applied by the driver, and, on the other hand, a reference braking force previously integrated into the vehicle. Thus, the less the driver anticipates the braking, the more the overconsumption is important.

In the present example, the braking force is determined from the measurement of the brake master cylinder pressure. In parallel, the reference braking force corresponds to a reference value of the pressure of the master cylinder, previously integrated into the vehicle.

Preferably, the reference values depend on the inclination of the vehicle (typically, uphill road, flat road, spinning wheel downhill), the reference behavior being different depending on this inclination. For example, on an uphill road, a first null reference value, on a flat road, a second positive reference value, and on a downhill road, a third reference value greater than one second.

In the present embodiment, the relative consumption corresponding to the anticipation of the braking phases is given by the formula

AConso _Brake = (P - P _ref ) x KCP x - _wheel x CSW

Where P is the value of the pressure of the master cylinder (in bar) measured by the first sensor;

[0056] _Ready is the reference value of the pressure of the master cylinder (in bar);

GW is the rotational angular velocity of a wheel (in rad.s ^-1 ) measured by the second sensor, and

CSW is a constant equal to the Willans specific consumption (in g / kW.h) identified in a nominal engine load zone from a map previously integrated into the vehicle giving the engine consumption according to its charge and its scheme.

A second displayed information is a deviation of the fuel consumption related to the change gear ratios by the driver. This difference in consumption is determined from the difference between, on the one hand, the engine speed, and, on the other hand, a reference engine speed previously integrated into the vehicle. So plus the change of speed ratio (ascent in gear or gearshift) is at a high speed, plus overconsumption is important.

In the present example, the engine speed is determined from the measurement of the rotational speed of the motor shaft. In parallel, the reference engine speed is deducted from the reference gear ratio previously integrated in the vehicle and the speed of the vehicle.

Preferably, as for deviation of the fuel consumption related to the anticipation of the braking phases, the reference values also depend on the inclination of the vehicle (typically, uphill road, flat road, downhill road) .

In the present embodiment, the relative consumption corresponding to the changes in the speed ratios is given by the formula

Where PMW is a constant equal to the average pressure of Willans (in bar);

Cyl is the value of the engine displacement (in I);

N is the value of the engine speed (in rpm ^"1 ) measured by the third sensor, and

N _ref is the reference value of the engine speed (in rpm ^"1 ).

A third displayed information is a deviation of the consumption related to the engine load during an acceleration phase. Indeed, during a significant demand for acceleration by the driver, the engine efficiency is degraded which corresponds to an increase in the "actual Willans specific consumption" (actual CSW) compared to the reference specific Willans consumption previously identified in a rated load area of the engine.

In the present example, the actual CSW of the engine is determined using a map previously integrated into the vehicle, giving the engine consumption according to its load and its speed. Willans specific consumption (CSW) is identified in advance from this mapping and used in all other criteria (evaluation of consumption differences related to the anticipation of braking phases and to the choice of the gearbox ratio. speed).

In the present embodiment, the relative consumption corresponding to the engine load during the acceleration phase is given by the formula

AConso Acceleration x {CSW, real CSW)

30 Where Cmot is the engine torque (in Nm) measured by the fourth sensor; and

CSWreeiie is the actual specific consumption of the engine determined from its speed and its load (in g / kW.h)

A fourth displayed information is a deviation of the consumption related to the speed of the vehicle. This difference in consumption is determined from the difference between the speed of the vehicle, and, secondly, a reference vehicle speed previously integrated into the vehicle. The energy losses beyond this reference speed are mainly in the aerodynamic resistance and rolling resistance of the tires. The higher the speed of the vehicle, the greater the overconsumption.

In the present embodiment, the relative consumption corresponding to the speed of the vehicle is given by the formula

^ _Consistency = (f ₀ {v - V _ref ) + ² - Vl _f ) + f ₂ (v ³ - V _r ³ _ef )) x CSW

Where V is the vehicle speed measured by the fifth sensor;

[0076] V _ref is the value of the reference vehicle speed; and

F ₀ , fi and f ₂ are the three factors of the road law of the vehicle.

F ₀ and fi correspond (to the units closely), respectively, to the rolling resistance coefficients CRR ₀ and CRRi used to determine the rolling resistance force according to the formula CRR ₀ + CRR x V. Similarly, f2 corresponds (to the nearest units) to the product of the vehicle penetration coefficient by the vehicle frontal area (ScX) used to determine the aerodynamic drag force in proportion to the square of the vehicle speed.

The invention is not limited to the present embodiment. It would thus be possible to have at least one additional consumption station. Thus, it would be possible to have a difference in consumption related to the quality and the sliding time of the clutch during the takeoff phases of the vehicle (starting from a zero speed).

In addition, the vehicle may not have a sensor to measure the engine torque, the value of the latter then being estimated.

Claims

1. A method of determining an economic nature of the driving of a motor vehicle by a driver, the method comprising a measuring step in which sensors measure parameters related to fuel consumption of the engine, and a step of displaying information on the economic nature of the pipe, characterized in that the information displayed is a difference in fuel consumption between, on the one hand, the consumption related to the driving of the driver determined from the measured parameters, and on the other hand, the consumption linked to a reference pipe determined from reference data previously integrated into the vehicle, one of the information displayed being a difference in fuel consumption related to the anticipation of the braking phases by the driver , the difference in fuel consumption related to the anticipation of the braking phases being determined from the between, on the one hand, a braking force applied by the driver, and, on the other hand, a reference braking force previously integrated into the vehicle.

2. Method according to claim 1, characterized in that the value of the reference braking force depends on the inclination of the vehicle.

3. Method according to one of claims 1 or 2, characterized in that the braking force is determined from the measurement of the pressure of a master cylinder of a vehicle brake, and the reference braking force corresponds to a reference value of the pressure of the master cylinder previously integrated into the vehicle.

4. Method according to one of claims 1 to 3, characterized in that the relative consumption corresponding to the anticipation of the braking phases is given by the formula

AConso _Frem = (P - P _ref ) x KCP x (O _wheel x CSW

Where P is the measured value of the master cylinder pressure (in bar);

_Ready is the reference value of the master cylinder pressure (in bar); KCP is a constant in the braking system to associate a master cylinder pressure and a braking torque at a wheel of the vehicle;

GW is the rotational angular velocity of a wheel (in rad.s ^"1 ), and

CSW is a constant equal to Willans' specific fuel consumption (in g / kW.h) identified in a nominal engine load zone from a map previously integrated into the vehicle, giving the engine consumption according to its load and his diet.

5. Method according to one of claims 1 to 4, characterized in that one of the information displayed is a deviation of the fuel consumption related to the change of speed reports by the driver.

6. Method according to claim 5, characterized in that the difference in fuel consumption related to changes in speed ratios is determined from the difference between, on the one hand, the engine speed, and, d On the other hand, a reference engine speed is a function of the reference gear ratio and the vehicle speed.

7. Method according to claim 6, characterized in that the value of the reference engine speed depends on the inclination of the vehicle.

8. Method according to one of claims 7 and 8, characterized in that the engine speed is determined from the measurement of the rotational speed of the motor shaft, and the reference engine speed corresponds to a reference value of the rotational speed of the motor shaft.

9. Method according to one of claims 5 to 8, characterized in that the relative consumption corresponding to the change in speed ratios is given by the formula

Where PMW is a constant equal to Willans average pressure (in bar);

Cyl is the value of the displacement of the engine (in I);

N is the value of the engine speed (in rpm ^"1 );

N _ref is the reference value of the engine speed (in rpm ^"1 ), and

10. Method according to one of claims 1 to 9, characterized in that one of the information displayed is a deviation of the consumption related to the engine load during an acceleration phase.

1 1. Method according to claim 1 0, characterized in that the difference in fuel consumption due to the engine load during the acceleration phase is determined from the difference between, on the one hand, the Willans specific fuel consumption. actual engine, and, on the other hand, the Willans specific reference consumption previously incorporated into the vehicle.

12. The method of claim 1 1, characterized in that the actual Willans specific consumption of the engine is determined using a map previously integrated into the vehicle giving the consumption of the engine according to its load and its speed, the specific consumption of Willans (CSW) is a constant identified from this map.

13. Method according to one of claims 10 to 1 1, characterized in that the relative consumption corresponding to the load of the motor in acceleration phase is given by the formula ^ Conso _{Accélémtion} = ^Cmot ^ ^X * ^' x {CSW _REAL - CSW)

Where Cmot is the actual engine torque (in Nm);

N is the value of the engine speed (in rpm ^"1 );

CSWieiie is the specific consumption of the engine determined from its speed and its load; and

CSW is a constant equal to Willans' specific consumption (in g / kW.h).

14. Method according to one of claims 1 to 13, characterized in that one of the information displayed is a deviation of the consumption related to the speed of the vehicle.

15. The method of claim 13, characterized in that the difference in fuel consumption related to the vehicle speed is determined from the difference between the speed of the vehicle, and a reference vehicle speed previously integrated in the vehicle.

16. Method according to one of claims 14 and 15, characterized in that the relative consumption corresponding to the speed of the vehicle is given by the formula

^ _Consistency = (f ₀ (V - V _ref ) + f ₁ (v ² - ¾) + ₂ (V ³ - ¾)) x CSW

Where f ₀ is the first factor of the vehicle's law of the road;

fi is the second factor of the road law of the vehicle;

f ₂ is the third factor of the road law of the vehicle;

V is the value of the vehicle speed;

V _ref is the value of the reference vehicle speed; and CSW is a constant equal to Willans' specific consumption (in g / kW.h).