FR3111592A1 - ELECTRIC VEHICLE AUTONOMY MANAGEMENT SYSTEM AND METHOD - Google Patents

Abstract

The invention relates to an autonomy management system (1) of an electric vehicle (2) connectable to a location database (1a) of charging stations (3), said system comprising an assistance request module ( 1b), a geolocation module (1d) of the electric vehicle (2), characterized in that it further comprises an autonomy calculation module (1c) for determining whether a journey between the electric vehicle (2) and a charging station (3) is possible on the basis of a state of charge of the battery of the vehicle (2), the location data (1a) and the geolocation of the vehicle (2), by modifying battery control parameters , and a battery calibration module (1f) for applying modified battery control parameters. The invention further relates to a method and a program based on such a system (1). Fig. 1

Description

SYSTEM AND METHOD FOR MANAGING ELECTRIC VEHICLE AUTONOMY

The invention relates to the field of motor vehicles with electric traction batteries, more particularly to systems for managing the autonomy of the battery of the electric motor.

With a view to reducing greenhouse gas emissions, the need to produce vehicles with electric traction motors (by simplification “electric vehicles”) has become significantly important. These vehicles include a gauge for monitoring a state of charge and an estimation of an autonomy, that is to say a distance that can be traveled on the basis of an estimated state of charge as well as the characteristics of the battery and the vehicle.

Unfortunately, at deep discharge levels, a driver may not have enough energy to reach a charging station under typical driving conditions.

An object of the invention is to provide a range management system making it possible to draw on residual energy from a highly discharged battery to allow the vehicle to move to reach a charging station, for example a service station, garage or dealership.

To achieve this objective, the invention proposes an electric vehicle autonomy management system that can be connected to a database of locations of charging stations, said system comprising an assistance request module, an electric vehicle geolocation module , characterized in that it further comprises an autonomy calculation module for determining whether a journey between the electric vehicle and a charging station is possible on the basis of a state of charge of the battery of the vehicle, of the data of location and geolocation of the vehicle, by modifying battery control parameters, and a battery calibration module for applying modified battery control parameters.

The autonomy management system may be part of an on-board computer of an electric vehicle and/or of a cloud computing system (known as a “cloud”). In the context of the invention, the term "module" is understood as a set of hardware elements and program code instructions to perform a given action.

Advantageously, the autonomy management system makes it possible to modify the battery control parameters so as to be able to draw the power necessary to move the vehicle, in particular in order to arrive at an identified charging station.

According to other aspects taken separately, or combined according to all the technically feasible combinations:

• the autonomy management system is also connectable to a road profile database comprising driving parameters, and the autonomy calculation module is configured to calculate an attainable speed according to the road profile of said route and corresponding road laws determining driving conditions; and or
• the battery control parameters include battery capacity, open circuit voltage and corresponding current or power limits; and or
• the battery calibration module is configured to apply a modified battery capacity by calculating its value from a current whose value is equal to the nominal capacity divided by an assistance factor X greater than a standard nominal factor Y, while allowing the vehicle to be moved; and or
• the autonomy management system further comprises a remote connection module configured for a remote transfer of initial data of the vehicle including the state of charge and the geolocation of the vehicle, the autonomy calculation module is implemented remotely, and resulting data including the modified battery control parameters, is transferred to the vehicle.

The invention further relates to a method for managing the range of an electric vehicle, comprising an assistance request step, a range calculation step to determine whether a journey between the electric vehicle and a charging station is possible on the basis of a state of charge of the battery of the vehicle, of location data of charging stations and of a geolocation of the vehicle, by modifying battery control parameters, and a battery calibration step for applying parameters of modified battery control.

According to other aspects taken separately, or combined according to all the technically feasible combinations:

• the autonomy calculation step is carried out to calculate an attainable speed according to a road profile of said route comprising driving parameters, and corresponding road laws determining driving conditions; and or
• in the battery calibration step, the modified battery control parameters include battery capacity, open circuit voltage and corresponding current or power limits; and or
• the autonomy management method further comprises a step of remote transfer of initial data from the vehicle comprising the state of charge and the geolocation of the vehicle, and the autonomy calculation step is implemented remotely, and the autonomy management method further comprises a step of transferring the resulting data comprising the modified battery control parameters, to the electric vehicle.

Another object of the invention relates to a computer program comprising program code instructions for the execution of the steps of the autonomy management method according to the invention, when said program runs on at least one computer.

The invention further relates to an electric vehicle comprising an autonomy management system according to the invention.

The invention will be further detailed by the description of non-limiting embodiments, and on the basis of the appended figure illustrating variants of the invention, namely which is a diagram of an autonomy management system according to a preferred variant of the invention in its operating environment.

The invention relates to an autonomy management system 1 for managing an autonomy of a battery of the electric traction motor of an electric vehicle 2.

The range of the battery of the electric motor is estimated on the basis of a state of charge of the battery of the electric vehicle 2, generally designated by the acronym SOC (State of Charge). In addition, the autonomy is evaluated according to the characteristics of the battery of the electric vehicle 2.

The object of the invention is to allow an increase in the autonomy of an electric vehicle 2 in the event of a request for assistance, in particular for an electric vehicle 2 with a power failure, in order to estimate whether the electric vehicle 2 could reach a charging station 3. This could be a charging station 3 at a service station, garage or dealership, or a combination of two or more of these.

To this end, the autonomy management system 1 can be connected to a database of locations of charging stations 1a. These are in particular GPS (Global Positioning System) positions associated with itineraries and preferably driving assistance information, namely for example traffic conditions, types of roads and authorized speeds. The autonomy management system 1 is preferably implemented partly in the vehicle 2 and partly remotely, in particular in an assistance server 4 of an assistance center 5. The server 4 can comprise a system of cloud computing (known as the “cloud”). Thus, the charging station location database 1a can be remote in the assistance server 4.

The autonomy management system 1 further comprises an assistance request module 1b. This is in particular a means of calling or alerting the assistance center from the vehicle 2, for example via an SOS call button 6 in the vehicle 2. The call can make it possible to put in communication the driver with the assistance center. An operator at the assistance center can then enter into conversation with the driver.

The range management system 1 further comprises a range calculation module 1c to determine whether a journey between the electric vehicle 3 and a nearby charging station 3 is possible. To this end, the autonomy management system 1 further comprises a geolocation module 1d of the electric vehicle 2, such as GPS equipment.

In particular, the autonomy calculation module 1c is implemented remotely in the assistance server 4, to preserve the residual energy of the vehicle 2. To this end, the autonomy management system 1 further comprises a remote connection module 1e configured for a transfer of initial data 7 from the vehicle 2 remotely. The transfer can be initiated by a helpdesk operator 5.

The transfer of initial data 7 is carried out via a mobile data network for remote computing. The assistance server 4 receives the initial data 7 from the vehicle 2. These are in particular the geolocation of the vehicle 2, the battery usage data, the battery parameters and the current state of charge. The initial data 7 may further comprise battery control parameters, or these may be standard and accessible to the assistance server 4. These battery control parameters are taken into account by the autonomy calculation module 1c and will be detailed below.

Preferably, the range calculation module 1c is configured to calculate an attainable speed according to the road profile of said route and the corresponding road laws. The road profile comprises driving parameters and the road laws make it possible to determine the course of journeys on roads as a function of said driving parameters, one can speak of driving conditions. The road laws are specific to the vehicle and precisely determine the progress of the journey in relation to the consumption and the state of charge of a given vehicle. The route profile and route laws can be taken from a navigation application called “Trip Planner”. These elements are preferably integrated into a single database 1a. More specifically, it is navigation data for electric vehicles making it possible to determine optimum routes to charging terminals 3. The road laws can be determined on the basis of maps and/or calculations taking into account in particular slopes and speeds required.

The calculation takes into account the geolocations of the vehicle 2 and of the charging stations 3, the state of charge, the battery control parameters, in particular the capacity. Indeed, the control of the battery is done from data on the battery cells provided by the manufacturers of the vehicle 2, in particular the capacity of the cells (C) which make up the battery in ampere-hours (Ah), the voltage at vacuum (OCV), the currents/powers available for a given state of charge and temperature.

The capacitance is usually measured for a current at C _nom /Y, where C _nom is the nominal capacitance value of the cell, and Y a so-called standard "nominal" factor depending on the field of application, generally equal to 3 in the automotive field. C _name can be split by different integer in different fields. The open circuit voltage (OCV) is a function of the state of charge (SOC) which itself depends on the capacitance (C).

These values that make up part of the autonomy management software are calibrated from tests on the cells/modules that make up the battery.

The invention proposes to push the tests further in order to obtain capacities for currents of C _nom /X, with X>Y, for example C _nom /5, C _nom /20, or even more, insofar as this makes it possible to move the vehicle 2. In addition to the capacitors, the invention proposes to obtain the no-load voltages for these new capacitors and the currents available for these new configurations. Thus, the value of the capacity increases, supplying a surplus of energy to the battery at lower but sufficient powers to tow the electric vehicle 2 to a nearby charging station 3. A calculation is made on the assistance server 4 to see if the path between the location of the electric vehicle 2 and the nearest charging stations 3 is possible with different calibrations of the battery.

At the end of the calculations of the autonomy calculation module 1c, if the result is positive, then the calibrations are made available in the battery management system. We can speak of a battery calibration module 1f configured to apply the modified battery control parameters, in particular the capacity of the battery, the open circuit voltage and the corresponding current or power limits, or any other battery parameters. The range management system 1 then enters “assistance” mode.

For this purpose, resultant data 8 comprising the modified battery control parameters resulting from the calculations, are transferred to the vehicle 2 via the remote connection module 1e. The battery management system is updated to integrate these new parameters and the retained capacity.

A modification to C _nom /20, for example, makes it possible to recover a few ampere-hours of capacity for a maximum given power (that is to say a power at current C _nom /20 at the maximum) and thus to drive up to at a charging station. This can save a driver from being stranded for several hours.

Advantageously, the autonomy management system makes it possible to draw residual power allowing the vehicle to be moved.

All the driver has to do is follow the directions to get to charging station 3.

The invention further relates to a method for managing the autonomy of an electric vehicle 2 substantially comprising steps for implementing the modules and actions of an autonomy management system 1 as described previously.

The autonomy management method comprises an assistance request step, in which a driver makes an assistance request, in particular with an assistance means such as the SOS call button 6.

The autonomy management method further comprises a step of transferring initial data 7 relating to the parameters of the vehicle 2, in particular at least the state of charge and the geolocation of the vehicle 2.

The autonomy management method further comprises a step of calculating autonomy to determine whether a journey between the vehicle 2 and a charging station 3 is possible on the basis of the state of charge, of terminal location data charging station 3 and the geolocation of the vehicle 2, by modifying battery control parameters, in particular by increasing its capacity calculated from a current C _nom /X with X>Y, in particular X>3 in the field automobile.

The autonomy management method further comprises a step of transferring the resulting data 8 to the vehicle 2. The resulting data 8 comprises the modified battery control parameters, in particular with the capacity C, calculated for a current = C _nom /X.

The autonomy management method further comprises a battery calibration step for applying modified battery control parameters, in particular with the capacity C _nom /X.

Another object of the invention relates to a computer program comprising program code instructions for the execution of the steps of the autonomy management method as described previously, or for the implementation of the actions of the management system autonomy as described above, when said program runs on at least one computer. The program can for example be loaded into an on-board computer of an electric vehicle.

The program in particular includes control instructions for applying modified battery control parameters, in particular with the capacity C _nom /X.

The invention further relates to an electric vehicle comprising a range management system or a program as described herein.

Claims (10)

Autonomy management system (1) of an electric vehicle (2) connectable to a location database (1a) of charging stations (3), said system comprising an assistance request module (1b), a for geolocation (1d) of the electric vehicle (2), characterized in that it further comprises a range calculation module (1c) for determining whether a journey between the electric vehicle (2) and a charging station (3 ) is possible on the basis of a state of charge of the battery of the vehicle (2), the location data (1a) and the geolocation of the vehicle (2), by modifying battery control parameters, and a module for battery calibration (1f) to apply modified battery control settings. Range management system (1) according to claim 1, further connectable to a database of road profiles (1a) comprising driving parameters, characterized in that the range calculation module (1c) is configured to calculate an attainable speed according to the road profile of said route and the corresponding road laws determining driving conditions. Autonomy management system (1) according to claim 1 or 2, characterized in that the battery monitoring parameters include battery capacity, open circuit voltage and corresponding current limits. Autonomy management system (1) according to Claim 3, characterized in that the battery calibration module (1f) is configured to apply a modified battery capacity by calculating its value from a current whose value is equal to the nominal capacity divided by an assistance factor X greater than a standard nominal factor Y, while allowing the vehicle (2) to be moved. Autonomy management system according to any one of claims 1 to 4, further comprising a remote connection module (1e) configured for remote transfer of initial data (7) of the vehicle (2) comprising the state charging station and the geolocation of the vehicle (2), characterized in that the autonomy calculation module (1c) is implemented remotely, and resulting data (8) comprising the modified battery control parameters, are transferred towards the vehicle (2). Method for managing the range of an electric vehicle (2), comprising an assistance request step, a range calculation step to determine whether a route between the electric vehicle (2) and a charging station (3) is possible on the basis of a state of charge of the battery of the vehicle (2), of location data of charging stations (1a) and of a geolocation of the vehicle (2), by modifying battery control parameters, and a battery calibration step to apply modified battery control parameters. Range management method according to claim 6, characterized in that the range calculation step is carried out to calculate an attainable speed according to a road profile of said route comprising rolling parameters, and corresponding road laws determining driving conditions. Autonomy management method according to claim 6 or 7, characterized in that in the battery calibration step, the modified battery control parameters comprise a battery capacity, an open circuit voltage and current limits or corresponding powers. Computer program comprising program code instructions for executing the steps of the autonomy management method according to any one of claims 6 to 8, when said program runs on at least one computer. Electric vehicle (2) comprising an autonomy management system (1) according to any one of claims 1 to 5.