FR3064236A1 - METHOD AND DEVICES FOR CALCULATING AN INSTANT ENERGY EFFICIENCY INDEX OF DRIVING A VEHICLE EQUIPPED WITH A MOTOR - Google Patents

Abstract

There is provided a method for calculating an instantaneous energy efficiency index for driving a vehicle (3) equipped with a motor (4) during a journey, solely implemented by technical means, comprising a step of extracting analysis data (7) from data records (5) from the vehicle and the engine, the data from the vehicle and the engine being recorded as a function of time.

Description

Technical area

The present invention relates to a method for calculating an instantaneous energy efficiency index for driving a vehicle equipped with an engine. It also relates to a device for implementing the method according to the invention and to a system comprising said device according to the invention. It also relates to a computer program product configured to implement the method according to the invention.

State of the art

There are known indicators giving isolated driving advice, such as gear change indicators for example by determining the speed of the gearbox which would be the most suitable and which the driver should select.

There is a need for information for a driver on the quality of his driving in real time.

An object of the invention is to meet this need.

Statement of the invention

At least one object of the invention is achieved with, according to a first aspect of the invention, a method of calculating an instantaneous energy efficiency index for driving a vehicle equipped with an engine during a path, preferably only implemented by technical means, comprising a step of extracting analysis data from data records coming from said vehicle and from said engine, the data coming from the vehicle and from the heat engine being recorded in function of time, the index being calculated as a function of the extracted data, the analysis data comprising at least:

an instantaneous factor, denoted f _e , of energy efficiency of said engine, and

an instantaneous factor, denoted fd, of the dynamics of said vehicle, and

- an instantaneous factor, noted f _v , of speed of said vehicle.

The means of implementing the method are typically:

- sensors to measure physical data from the vehicle,

A recording unit for recording data coming from the vehicle and the engine as a function of time, said data coming in particular from sensors for measuring physical data of the vehicle,

a data extraction unit, for example produced in the form of a calculation unit, for extracting the analysis data from the data records recorded in the recording unit,

a calculation unit, for example different from the data extraction unit, or identical, for calculating the instantaneous energy efficiency index from the three cited factors included in the analysis data.

The vehicle can be a motor vehicle or a two-wheel motorcycle, or a utility vehicle or even a heavy vehicle.

The engine can be a heat engine or an electric motor. Advantageously, the engine can be a heat engine and the instantaneous efficiency factor f _e can be determined from an instantaneous effective specific consumption of said heat engine.

The actual instantaneous specific consumption can be determined from the speed and the engine load.

The actual specific consumption can be a measured data, or it can be reconstructed from a standard Willans model (at least differentiated for petrol and diesel engines). The Willans model also takes the engine speed and load as input, in parameters of Willans specific consumption and Willans average pressures.

According to one embodiment, the engine is powered by a fuel having a lower calorific value, the instantaneous efficiency factor fe being determined as proportional to the inverse of the product of the instantaneous actual specific consumption by said lower calorific value, which can be written: f _e oc ¹

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Preferably, the instantaneous energy efficiency factor f _e of the vehicle can be a real number between 0 and 1.

- 3 In particular, the factor fe can be determined by the formula:

r _ 3600X10 ^{3 e _} CSExPCI '

The factor f _e can be determined from the engine speed and the engine load.

Depending on a given engine load, the instantaneous energy efficiency factor can be the result of the application of a continuous function with value in the interval [0..1], increasing (or constant) over a speed interval [0, r _op t] and then decreasing (or constant), where r _op t is the optimal regime for said load.

Depending on a given engine speed, the instantaneous energy efficiency factor can be the result of the application of a continuous function with value in the interval [0..1], increasing (or constant) over a speed interval [Charginit, Charge _op t] and then decreasing (or constant), where Charginit is an initial charge, often around 5%, for said regime and Charge _op t is the optimal charge for said regime, and is often located around 90% of the maximum load.

The following table can be used to determine an instantaneous energy efficiency factor from engine speed and engine load.

postman efficiency energetic instantaneous diet rpm) 0 100 0 150 0 200 0 250 0 300 0 350 0 400 0 450 0 500 0 charge (%) 5 0.02 0.12 0.18 0.20 0.16 0.12 0.10 0.06 0.02 0.00 50 0.09 0.54 0.81 0.90 0.72 0.54 0.45 0.27 0.09 0.00 90 0.10 0.60 0.90 1.00 0.80 0.60 0.50 0.30 0.10 0.00 10 0 0.08 0.45 0.68 0.75 0.60 0.45 0.38 0.23 0.08 0.00

The instantaneous energy efficiency factor can be determined as equal to 1 at zero load. Thus, a driver's foot lift is valued in the calculation of the energy efficiency index.

Of course, for a load or a speed not listed in this table, it is possible to interpolate an instantaneous energy efficiency factor from the other values of instantaneous energy efficiency factor.

When the engine is a heat engine, the efficiency factor can be calculated from the minimum specific consumption CSEmin of said

- 4 motor. The factor can be calculated by the following formula: f _e = CSEmin / CSE.

According to one possibility, the instantaneous dynamic factor fd of the vehicle is a real number between 0 and 1, determined from the filtered longitudinal acceleration of the vehicle.

The longitudinal acceleration of the vehicle can be determined by deriving the longitudinal speed of the vehicle or from a measurement of an accelerometer arranged on, or transported by, said vehicle.

The filtered longitudinal acceleration can be determined from filtering the longitudinal acceleration by a low-pass filter, preferably of the first order. The low-pass filter can for example have a time constant of 0.5 seconds to 3 seconds.

The filtered longitudinal acceleration can be counted positively when the vehicle is braked and negatively if the vehicle is accelerating.

The instantaneous dynamic factor can be the result of the application of a continuous function with value in the interval [0..1], increasing (or constant) of the filtered longitudinal acceleration counted positively in the event of braking. a vehicle.

The following table can be used to determine an instantaneous dynamic factor based on a filtered longitudinal acceleration value counted positively when braking a vehicle.

filtered longitudinal acceleration (m.s-2) -5 -3 -2 0 5 10 instant dynamic factor 0.00 0.60 1.00 1.00 1.00 1.00

Of course, for a longitudinal acceleration measurement not listed in this table, it is possible to interpolate an instantaneous dynamic factor from the other instantaneous dynamic factor values. For example, we understand that for any filtered longitudinal acceleration of a value greater than or equal to -2 ms ^-2 , the instantaneous dynamic factor is equal to 1. This coefficient makes it possible to encourage driving behavior with a small variation d acceleration while not penalizing light braking or emergency braking necessary in certain situations, such as when a person crosses in front of the vehicle.

- 5 According to one possibility, the instantaneous vehicle speed factor is a real number between 0 and 1, determined as a function of the instantaneous speed of the vehicle.

The instantaneous speed factor can be the result of the application of a continuous function with value in the interval [0..1], decreasing (or constant) of the instantaneous speed of the vehicle.

The following table can be used to determine the instantaneous vehicle speed factor based on a value of an instantaneous vehicle speed.

Vehicle speed (km / h) 0 100 110 130 150 200 instant speed factor 1.00 1.00 0.90 0.80 0.50 0.00

Of course, for an instantaneous speed measurement of the vehicle not listed in this table, it is possible to interpolate an instantaneous speed factor from the other instantaneous speed factor values. For example, we understand that for any instantaneous speed of a value less than or equal to 100 km / h, the instantaneous speed factor is equal to 1.

Advantageously, the instantaneous energy efficiency index is the product of the instantaneous factor of energy efficiency of the engine, the instantaneous factor of vehicle dynamics, and the instantaneous factor of vehicle speed. This product can be converted into a percentage to generate an instantaneous instant energy efficiency index.

According to one embodiment, the data originating from the vehicle and from the engine can be retrieved in real time by a vehicle communication interface during the journey of the vehicle.

Preferably, the vehicle communication interface is connected to an OBD socket on the vehicle.

The instant energy efficiency index can be displayed in real time by a display device. The energy efficiency index can be represented in binary form, numbers, bars, gauges or even a curve illustrating its evolution over time.

According to a second aspect of the invention, there is provided a device for calculating an instantaneous energy efficiency index for driving a vehicle equipped with an engine during a journey, comprising a unit

- 6 data extraction, a data recording unit and a calculation unit, the data recording unit being configured to record data from the vehicle and the engine, the data extraction unit being configured to generate analysis data from the recorded data from the recording unit, and the calculation unit being configured to calculate the instantaneous energy efficiency index from the analysis data, the analysis data including at least:

- an instantaneous factor, denoted fe, of energy efficiency of said engine,

an instantaneous factor, denoted fd, of the dynamics of said vehicle, and

- an instantaneous factor, noted fv, of speed of said vehicle.

The calculation unit can be a microprocessor.

The data extraction unit can be a microprocessor, possibly different from that of the calculation unit. The data extraction unit can equip the vehicle.

The recording unit can be a memory, for example a read only memory, fitted to the vehicle.

According to a third aspect of the invention, a system is proposed comprising a calculation device according to the second aspect of the invention, or one or more of its improvements, and a display device, said display device being configured to display the instant energy efficiency index from the computing unit of the computing device.

The display device can be a smartphone screen or a display device fitted to the vehicle.

Advantageously, the calculation unit and the display device are arranged within the same device. The device is for example a smartphone.

According to one embodiment, the recording unit can equip the vehicle and be connected to a communication interface of said vehicle, the system according to the invention possibly further comprising a communication unit arranged to communicate with said communication interface and receive registration data.

- 7 3064236

The calculation unit, the display device and the data extraction unit can be integrated into a smartphone, which can include wireless communication means arranged to communicate with communication means of the communication unit. communication and receive registration data.

Alternatively, the recording unit can be external to the vehicle, said vehicle being equipped with a communication interface arranged to communicate the data originating from the vehicle and from the engine, the system according to the invention possibly further comprising a communication unit. arranged to communicate with said communication interface to receive said data from the vehicle and the engine.

According to a fourth aspect of the invention, there is provided a computer program product, downloadable from a communication network and / or stored on a medium readable by computer and / or executable by a microprocessor, which, when executed , implements the simulation method according to the first aspect of the invention, or one or more of its improvements.

The invention consists, apart from the arrangements set out above, of a certain number of other arrangements which will be more explicitly discussed below in connection with an exemplary embodiment described with reference to the appended drawing, but which n 'is in no way limiting.

Description of the figures

Other features and advantages of the invention will appear on reading the detailed description of implementations and embodiments which are in no way limitative, with reference to the appended figures in which:

- Figure 1 is a diagram illustrating an embodiment of a system according to the invention.

Description of the invention

Since this embodiment is in no way limiting, it will be possible in particular to produce variants of the invention comprising only a selection of characteristics described below, as described or generalized, isolated from the other characteristics described, if this selection of

- 8 characteristics is sufficient to confer a technical advantage or to differentiate the invention from the state of the art.

There is now described, with reference to FIG. 1, an embodiment of a device 1 according to the invention, at the same time as the method implemented in this device.

a data recording unit 2 fitted to a vehicle 3 provided with a heat engine 4, configured to record data 5 coming from the vehicle 3 and from the heat engine 4,

a data extraction unit 6 configured to generate analysis data 7 from recorded data 8 coming from the recording unit 2,

a calculation unit 9 configured to calculate an instant energy efficiency index from the analysis data 7.

The energy efficiency index is calculated as a function of the data 7 of analyzes, which include at least:

- an instantaneous energy efficiency factor, noted f _e , of motor 4, which is a real number between 0 and 1,

an instantaneous dynamic factor, denoted fd, of the vehicle 3, which is a real number between 0 and 1, and

- an instantaneous speed factor, noted f _v , of vehicle 3, which is a real number between 0 and 1.

The table is used to determine the instantaneous fuel efficiency factor from the engine speed and the engine load of the vehicle engine.

Instant energy efficiency factor diet rpm) 0 1000 1500 2000 2500 3000 3500 4000 4500 5000 charge (%) 5 0.02 0.12 0.18 0.20 0.16 0.12 0.10 0.06 0.02 0.00 50 0.09 0.54 0.81 0.90 0.72 0.54 0.45 0.27 0.09 0.00 90 0.10 0.60 0.90 1.00 0.80 0.60 0.50 0.30 0.10 0.00 100 0.08 0.45 0.68 0.75 0.60 0.45 0.38 0.23 0.08 0.00

- 9 The following table is used to determine an instantaneous dynamic factor based on a filtered longitudinal acceleration value counted positively when braking a vehicle.

filtered longitudinal acceleration (m.s-2) -5 -3 -2 0 5 10 instant dynamic factor 0.00 0.60 1.00 1.00 1.00 1.00

The following table can be used to determine the instantaneous vehicle speed factor based on a value of an instantaneous vehicle speed.

Vehicle speed (km / h) 0 100 110 130 150 200 instant speed factor 1.00 1.00 0.90 0.80 0.50 0.00

More specifically, the instantaneous energy efficiency index is the product of the instantaneous engine energy efficiency factor, the instantaneous vehicle dynamics factor, and the instantaneous vehicle speed factor.

In the example shown, the device 1 is implemented within a system 100 according to the invention. The system 100 represented also comprises:

a communication interface 101 configured to retrieve in real time the data 5 coming from the vehicle 3 and from the engine 4, the communication interface 101 being connected to an OBD socket 102 of the vehicle,

a communication unit 103 arranged to communicate with the communication interface 101 and to receive the data 8 recorded, and more precisely connected to the OBD socket 102,

a display device 104 configured to display the instantaneous energy efficiency index coming from the unit 9 of calculation of the calculation device.

In the example shown in Figure 1, the calculation unit 9 and the display device 104 are arranged within the same device, here a smartphone.

According to a variant, the calculation unit, the display device and the data extraction unit could be integrated within a smartphone, which comprises wireless communication means arranged for

- 10 3064236 communicate with communication means of the communication unit and receive the recording data.

Of course, the invention is not limited to the examples which have just been described and numerous modifications can be made to these examples without departing from the scope of the invention. In addition, the different characteristics, forms, variants and embodiments of the invention can be associated with each other in various combinations as long as they are not incompatible or mutually exclusive of each other.

Claims (16)

Claims 1. Method for calculating an instantaneous energy efficiency index for driving a vehicle (3) equipped with an engine (4) during a journey, only implemented by technical means, comprising a step extracting analysis data (7) from data records (5) from the vehicle and the engine, the data from the vehicle and the engine being recorded as a function of time, the energy efficiency index instant being calculated as a function of the extracted data, the analysis data comprising at least: - an instantaneous energy efficiency factor, noted f _e , of said engine, an instantaneous dynamic factor, denoted fd, of said vehicle, and - an instantaneous speed factor, noted f _v , of said vehicle. 2. Method according to claim 1, wherein the engine is a heat engine and the instantaneous efficiency factor f _e is determined from an instantaneous effective specific consumption of said heat engine. 3. Method according to the preceding claim, wherein the engine is powered by a fuel having a lower calorific value denoted PCI, the instantaneous factor f _e of energy efficiency being determined as proportional to the inverse of the product of the instantaneous actual specific consumption. , denoted CSI, of the engine, by said lower calorific value, which can be written: f (y _1_ ^{e K} CSExPCI ' 4. Method according to any one of the preceding claims, in which the instantaneous energy efficiency factor of the vehicle is a real number between 0 and 1, determined from the engine speed and the engine load. - 12 5. Method according to any one of the preceding claims, in which the instantaneous dynamic factor fd of the vehicle is a real number between 0 and 1, determined from the filtered longitudinal acceleration of the vehicle. 6. Method according to any one of the preceding claims, in which the instantaneous vehicle speed factor is a real number between 0 and 1, determined as a function of the instantaneous speed of the vehicle. 7. Method according to any one of the preceding claims, in which the instantaneous energy efficiency index is the product of the instantaneous engine energy efficiency factor, the instantaneous vehicle dynamics factor, and the instantaneous speed factor of the vehicle. 8. Method according to any one of the preceding claims, in which the data originating from the vehicle and from the engine are recovered in real time by a communication interface (101) of the vehicle during the journey of the vehicle. 9. Method according to the preceding claim, wherein the vehicle communication interface is connected to an OBD socket (102) of the vehicle. 10. Method according to any one of the preceding claims, in which the instantaneous energy efficiency index is displayed in real time by a display device (104). 11. Device (1) for calculating an instantaneous energy efficiency index for driving a vehicle (3) equipped with an engine (4) during a journey, comprising a recording unit (2) data, a data extraction unit (6) and a calculation unit (9), the unit - 13 data recording being configured to record data (5) from the vehicle and the engine, the data extraction unit being configured to generate analysis data (7) from the data (8) recorded from the recording unit, and the calculating unit being configured to calculate the instantaneous energy efficiency index from the analysis data, the analysis data comprising at least: an instantaneous energy efficiency factor, denoted fe, of said engine, and an instantaneous dynamic factor, denoted fd, of said vehicle, and - an instantaneous speed factor, noted fv, of said vehicle. 12. System (100), comprising a calculation device (1) according to the preceding claim and a display device (104), said display device being configured to display the instantaneous energy efficiency index coming from the calculation unit (9) of the calculation device. 13. The system of claim 12 wherein the calculation unit and the display device are arranged within the same device. 14. System according to one of claims 12 or 13, wherein the recording unit equips the vehicle and is connected to a communication interface (101) of said vehicle, said system further comprising a communication box (103). arranged to communicate with said communication interface and receive the recording data. 15. System according to the preceding claim, in which the calculation unit, the display device and the data extraction unit are integrated within a smartphone, which comprises wireless communications means arranged to communicate with means - 14 3064236 communication from the communication box and receive the recording data. 16.Product computer program, downloadable from a communication network and / or stored on a computer-readable medium and / or executable by a microprocessor, which, when executed, implements the simulation method according to the 'one of claims 1 to 10.