FR3134355A1 - METHOD FOR DETERMINING THE RANGE OF AN ELECTRICALLY PROPULSION VEHICLE - Google Patents

Abstract

Method for determining the remaining kilometer range, at a given instant, of an electric propulsion mode of a motor vehicle, this method carrying out at any instant steps of: - determining an energy state of a traction battery BR1, - determination of a remaining energy capacity of the traction battery BR1 - determination of a state of charge of the traction battery BR1, - display of the remaining kilometer range of the vehicle in electric propulsion mode, and - as long as the state of charge is between 100% inclusive and a first state of charge threshold, determination of the remaining kilometer range at the given time by dividing the remaining energy capacity at the given time by a predetermined and constant energy consumption per kilometer. Figure 1.

Description

METHOD FOR DETERMINING THE RANGE OF AN ELECTRICALLY PROPULSION VEHICLE

The invention relates to the determination of a remaining kilometer range of an electric-powered vehicle or a vehicle capable of operating with a mode of electric propulsion whose electrical energy is provided by a battery, called a traction battery, powering a electrical consumer, in particular an electric motor machine.

It is known that these batteries are monitored by a battery controller, this battery controller determining for example and in a known manner a state of charge of the battery, a state of health of the battery (aging of the components), one or more voltages , battery currents and temperatures, and a battery energy state.

The energy state of the battery will be understood throughout the text of this document as the quantity of energy available for the operation of current-consuming components coupled to the battery or for the operation of the vehicle. This quantity is for example expressed as an absolute value in Watt Hours or in joules, or as a percentage compared to a reference energy quantity corresponding for example when the state of charge is 100%.

This energy state is input data for determining the remaining battery life. This remaining autonomy, depending on the application of the battery, can be expressed in remaining operating time and/or in remaining travelable distance for a motor vehicle for example. This remaining autonomy is also a function of a use or driving profile for a vehicle, this profile defining a level of power consumed or regenerated (for example a vehicle including a braking energy regeneration system), or, if the voltage varies little, equivalently a current consumption profile of the battery as a function of time. This consumption profile, also called use or driving profile, is for example a projection made from the data of a last use of the battery, or a predetermined typical profile, representative of a standard use of the battery, or again of a programmed route of the vehicle, but many other examples are possible.

Most often, the battery controller determines this energy state from maps resulting from measurements made on the bench or during the development of the battery. Certain methods propose to determine this energy state for a battery supplying an electrical consumer. For example, we know from patent document EP-A1-3245096 a process determining such an energy state. This method for determining a value of the energy state of the battery comprising the steps of:
- determine the state of charge as a measure of the current capacity of said battery; And
- determine said energy state as an indication of at least the remaining charge and discharge energy of said battery; said method comprising calculating and determining said value of the energy state based on the following steps:
- determining an energy state for charging said battery, based on said state of charge of said battery, as calculated between the current state of charge and a highest permitted state of charge in which no additional charging of the battery is not authorized, for a given battery current,
- determining an energy state for discharging said battery, based on said state of charge of said battery, as calculated between a lowest permitted state of charge, in which the battery must be charged in order to enable operation of the consumer electrical, and the current state of charge for a given battery current, in which
- said highest authorized state of charge and said lowest authorized state of charge are linked to the operation of said electrical consumer and vary depending on an operating mode of said vehicle or electrical consumer during the charging or discharging of said battery in wherein the energy state of the battery is determined from the area under a curve representing the relationship between the battery voltage and the state of charge, wherein the battery voltage is the sum of an open circuit voltage and a voltage drop, and wherein the actual mode of the vehicle which is determined by the actual operating conditions of the vehicle is used to predict the rechargeable battery current applied or withdrawn, the state of charge highest allowed and lowest state of charge allowed to charge or discharge the battery.

This process further comprises the steps of:
- determine said energy state as a function in addition of at least one of the following battery parameters:
- the capacity of the cell;
- the current state of charge;
- resistive and non-resistive losses; And
- temperature ;
- in which at least one of said battery parameters depends on said mode.

This method, or this cartographic method, will for example be used to determine the energy state according to the present invention.

Whatever the method used, fundamentally the energy state is influenced by:
- a battery temperature,
- battery voltage,
- a state of health of the battery, on which the evolution of the internal resistance of the battery directly depends.

This same document EP-A1-3245096 further presents, in the prior art, methods for determining a state of charge of such a battery, in particular but not only, from a no-load voltage of the battery, method known to those skilled in the art. For example, the cited patent document US-A1-2012112754 determines state of charge thresholds depending on the state of health of the battery. For example, the cited patent document EP-A1-2178187 determines the state of charge of the battery from the state of charge of each cell of the battery. All of these methods for determining the state of charge are known to those skilled in the art and will for example be used to determine the state of charge according to the present invention.

The state of health depends, for example, on the number of discharge or recharge cycles, and the power or intensity of each of these cycles. This state of health also depends on the age of the battery components and in particular its electrochemical cells since their moment of manufacture, and/or the maximum or minimum temperatures reached by each of these cells and/or the quantity of energy received and supplied by each of these cells.

We will understand by state of health, throughout the text of this document, the relationship between:
- the maximum energy capacity (at full charge) in the current aging state of the battery, and
- the maximum capacity (at full charge) in new energy of the battery, each of these two capacities being expressed in Ampere Hour or KWh, the state of health being expressed as a percentage.

We also know complex mileage range determinations, taking into account a planned future journey for example, or as in patent document FR-A1-3078670 the more or less sporty behavior of the driver.

Unfortunately these processes for determining kilometer ranges are not only complex to implement for an insignificant improvement in precision, but also the future route is not always available or programmed, making this process ineffective.

Conversely, we know simple determinations, based on a current state of charge of a battery powering an electric motor machine and on an average energy consumption of the vehicle (from the energy state of the battery) in relation to the distance already traveled, but whose autonomy displayed is very fluctuating depending on the type of driving in progress. For example, the variation will be sudden when the vehicle goes from traffic jam type driving to highway type driving, and the driver is often disoriented when faced with this fluctuating value.

The aim of the invention is to remedy this lack by proposing a simple determination method while displaying autonomy consistent with the capabilities of the vehicle.

To this end, the subject of the invention is a method for determining the remaining kilometer range, at a given instant, of a mode of electric propulsion of a motor vehicle, this vehicle comprising:
- a set of consumer devices comprising an electric driving machine capable of propelling the vehicle for the electric propulsion mode,
- a traction battery suitable for powering all the consumer devices,
- a means of recharging the traction battery,
- a battery controller suitable for implementing the process,
this process executing at any time steps of:
- determination of an energy state of the traction battery,
- determination of a remaining energy capacity of the traction battery,
- determination of a state of charge of the traction battery,
- display of the remaining kilometer range of the vehicle in electric propulsion mode.
This process is such that it performs steps of:
- as long as the state of charge is between 100% inclusive and a first state of charge threshold, determination of the remaining kilometer range at the given time by dividing the remaining energy capacity at the given time by consumption kilometer of predetermined and constant energy.

The remaining mileage range of the electric propulsion mode of the motor vehicle is of course the mileage that this vehicle can still cover with the electric propulsion mode. If the vehicle is hybrid-powered, for example also comprising an internal combustion powertrain, called a thermal engine, the remaining kilometer range of the vehicle is the addition of the remaining range of the electric propulsion mode and the range remaining thermal propulsion mode. The invention concerns only the remaining kilometer range of the electric propulsion mode and can be applied both to this hybrid vehicle and to a vehicle with rechargeable electric propulsion only.

The energy state of the traction battery is a characteristic of the battery known to those skilled in the art and is not the subject of this invention, even if it uses the result. We will understand by energy state of the battery, throughout the text of this document, the quantity of energy of the traction battery for the operation of all the consuming devices. This quantity is for example expressed as an absolute value in Watt Hours or in joules, or as a percentage compared to a reference energy quantity for example when a state of charge is at 100%.

In the context of this invention, the state of energy will be expressed in absolute value in Watt hour or KWh for Kilo Watt hour.

This energy state is input data for determining the remaining mileage range of the traction battery.

Examples of determining this energy state applicable to the invention have previously been given.

The remaining energy capacity of the traction battery according to the invention is the difference between two energy states: the first is the energy state at the instant considered, for example calculated according to the previous method, and the second is a minimum energy state admissible by the traction battery. This minimum admissible energy state corresponds to an energy state that is not zero but close to 0 KWh, for example between 0.5 and 5 KWh for a given traction battery for a maximum energy state of 50 KWh. This minimum admissible energy state must not be exceeded otherwise the integrity of the electrochemical cells of the battery will be seriously degraded, or even the traction battery will permanently fail. This feature will be described in detail in the description of the .

Traction battery will be understood throughout the text of this document to mean an assembly comprising at least one battery module containing at least one electrochemical cell. This battery possibly comprises electrical or electronic means for managing the electrical energy of this at least one module. When there are several modules, they are grouped together in a casing and then form a battery pack, this battery pack often being referred to by the English expression "battery pack", this casing forming a hermetic enclosure and generally including a mounting interface , and connection terminals.

Furthermore, by electrochemical cell we will understand throughout the text of this document, cells generating current by chemical reaction, for example of the lithium-ion (or Li-ion) type, of the Ni-Mh type, or Ni-Cd or still lead.

The state of charge of the traction battery is also a characteristic well known to those skilled in the art and determination methods applicable to the invention have already been presented previously.

The main characteristic of predetermined and constant energy consumption per kilometer is that it is invariable. Its value as such is not arbitrary, as we will see below, but the essential thing for the invention is that it is constant. Thus, according to the invention, each time the state of charge is between 100% and this first threshold, the only parameter influencing the determination of the remaining kilometer autonomy at the given instant is the remaining energy capacity at the given moment. the given moment which itself is only dependent on the state of energy at the given moment. Thus, after a significant recharge of the traction battery and/or a significant energy state level, the remaining mileage range is not disturbed by mileage energy consumption unsuitable for the current journey, and is more close to the value that the driver can logically expect after a complete recharge (100% state of charge), for example. This autonomy, however, remains a function of the state of energy which itself varies depending on the state of health as described previously and the temperature of the battery cells. Thus this mileage autonomy, for example at a state of charge of 100%, will logically decrease with the age of the traction battery, in a consistent and expected manner.

According to one embodiment of the invention, the first state of charge threshold is between 70 and 90% inclusive, in particular 80%.

According to one embodiment of the invention, the predetermined and constant kilometric energy consumption is memorized by the battery controller and corresponds to a new energy capacity of the battery at a state of charge of 100%, divided by an autonomy approved mileage of the vehicle.

The approved mileage range of the vehicle is a constant depending on the vehicle and the type of traction battery. It is determined as follows: All manufacturers of electric vehicles must have the autonomy of their vehicle approved by the competent organizations in each geographical area where the manufacturers want to sell their electric vehicles.

For a vehicle with purely electric propulsion, this approval consists of placing this vehicle whose traction battery is 100% charged on a dynamometer and making the vehicle follow a succession of vehicle speeds. When the vehicle can no longer follow the speeds imposed on the cycle, the test is stopped and we look at the number of kilometers traveled which become the approved kilometer autonomy of the vehicle for all vehicles produced.

The new energy capacity of the battery at a state of charge of 100% is the difference between the new energy state of the battery at a state of charge of 100% and the minimum admissible energy state at new by the traction battery.

This provision allows that, when new and for a state of charge of 100%, the remaining kilometer range determined will be equal to the approved kilometer range.

According to a variant embodiment of the invention, the predetermined and constant kilometric energy consumption is memorized by the battery controller and corresponds to the smallest energy capacity at new for a state of charge of 100% among batteries of a park of this battery, divided by the approved kilometer autonomy of the vehicle. The definitions of the new energy capacity and the approved mileage range of the vehicle are the same as previously.

This provision allows that, whatever the vehicle considered, when new and for a state of charge of 100%, the remaining kilometer autonomy determined will be equal to or greater than the approved kilometer autonomy. Indeed, if the vehicle considered has a new energy capacity for a 100% state of charge which is greater than the smallest new energy capacity for a 100% state of charge among the batteries in the fleet of this battery, this remaining kilometer range determined and displayed will be greater than the approved kilometer range.

According to one embodiment of the invention, this method executes at any time a step of determining an average energy consumption per kilometer carried out by all the consuming devices, and as long as the state of charge is between the first state of charge threshold included and a third state of charge threshold included strictly lower than the first state of charge threshold, executes a step of:
- determination of an average convergence kilometer energy consumption,
- determination of the remaining kilometer range at the given time by dividing the remaining energy capacity at the given time by the average convergence kilometer energy consumption,
this average convergence kilometer energy consumption being such that:
- it is equal to the value of the predetermined and constant kilometric energy consumption if the state of charge is equal to the first state of charge threshold,
- it is equal to the value of the average kilometric energy consumption achieved if the state of charge is equal to the third state of charge threshold,
- and it evolves linearly between the value of the predetermined and constant kilometric energy consumption and the value of the average kilometric energy consumption achieved for each value of the state of charge between the first state of charge threshold and the third state of charge threshold.

This arrangement makes it possible to move from the value of the predetermined and constant kilometer energy consumption to the value of the average kilometer energy consumption achieved without displaying a sudden variation in the remaining kilometer autonomy, hence the term convergence.

According to one embodiment of the invention, the third state of charge threshold is between 40% and 60% inclusive, in particular 50%.

According to one embodiment of the invention, this method determines an initial instant equal to the instant of the end of a battery recharge cycle during which the state of charge reaches or exceeds a second state threshold. of charge of the battery greater than the first state of charge threshold, and executing at any instant a step of determining a mileage traveled since this initial instant, the average energy consumption per kilometer achieved corresponding to a cumulative energy consumption of all consumer devices from the initial instant to the given instant, divided by the mileage traveled at the given instant.

This first arrangement makes it possible to determine an average energy consumption per kilometer achieved which is not very sensitive to sudden and occasional variations in energy consumption which are not necessarily representative of the current driving cycle of the vehicle, for example when overtaking another vehicle. Thus the remaining kilometer autonomy will have a substantially linear evolution over time, and potentially optimistic.

According to one embodiment of the invention, the second state of charge threshold is between 90% and 100% inclusive.

According to a variant embodiment of the invention, the average energy consumption per kilometer achieved corresponds to a sliding average of a cumulative energy consumption of all the consumer devices over a predetermined mileage traveled ending at the given instant, in particular of 50 km.

This second provision makes it possible to determine an average energy consumption per kilometer achieved which adapts more quickly to variations in driver behavior and/or the profile of the road, and is more sensitive to sudden and occasional variations in energy consumption which are not not necessarily representative of the current driving cycle of the vehicle, for example when overtaking another vehicle. Thus the remaining kilometer autonomy will have a less linear evolution over time compared to the first provision, and potentially pessimistic.

Of course, the method can combine the first and the second arrangement by determining for example an average of these two determinations of average energy consumption per kilometer achieved.

It will be noted that, throughout the text of this document, consumer devices will be understood to mean any device capable of consuming energy from the traction battery during a driving cycle of the vehicle, that is to say for a period of time. where the vehicle is capable of moving forward by means of the electric driving machine, even if some of these devices can be reversible and charge, for short periods of time, the traction battery, in particular the electric driving machine when it is reversible. For example, if the means of recharging the traction battery is an on-board charger, reversible or not, requiring the immobilization of the vehicle in order to be connected to a terrestrial electrical network, it is not, according to the meaning of the invention , a consumer device.

Thus for these two cases of determining the average energy consumption per kilometer achieved, the cumulative energy consumption of all the consuming devices can be determined by several different methods. For example :
- a first method by only accumulating the energy consumption of each consumer, and the energy generated temporarily by one of the reversible consumers is not deducted from this accumulation and is ignored except of course for the determination of the state of energy and charge, or
- a second method by deducting the energy temporarily generated from this accumulation.

The first method will result in a determination of the overestimated average energy consumption per kilometer achieved, the process will then determine a pessimistic (low) remaining kilometer autonomy because in reality during the journey the vehicle will perhaps have the possibility of generating energy by one of its reversible consumer devices, while the second method will result in a determination of the average energy consumption per kilometer achieved which is underestimated, and the method will then determine an optimistic remaining kilometer autonomy (strong) because in reality during the journey the vehicle will perhaps not be able to generate energy through one of its reversible consumer devices. Of course, we can combine these two methods by, for example, taking an average of the optimistic determination and the pessimistic determination, or a weighted average or any other method.

In addition, the cumulative energy consumption of all consuming devices can be determined directly or indirectly.

For example, for a direct determination, the process could:
- Integrate over time a measurement of the power consumed by each consumer device (measurement of voltages and currents), or of the power, or
- Integrate over time a measurement of the power consumed at the terminals of the traction battery, which is for example a very simple way of proceeding to automatically deduce the energy generated by the reversible consumer device, in connection with the second method described previously.

For example, for an indirect determination, the method could include a certain number of behavior models of each consumer device and, based on control instructions for these devices, calculate the power consumed for each consumer device.

According to one embodiment of the invention, this method executes a step of determining the remaining kilometer range at the given time by dividing the energy state at the given time by the average kilometer energy consumption achieved. at the given time as long as the state of charge is between 0% inclusive and the third state of charge threshold.

The invention further relates to a motor vehicle comprising:
- a set of consumer devices comprising an electric driving machine capable of propelling the vehicle for the electric propulsion mode,
- a traction battery suitable for powering all the consumer devices,
- a means of recharging the traction battery,
- a battery controller comprising the means of acquisition, processing by software instructions stored in a memory as well as the control means required to implement a method as previously described.

According to one embodiment of the invention, the electric propulsion mode is the only propulsion mode of the vehicle.

According to one embodiment of the invention, the means for recharging the battery is an on-board charger capable of being connected to a terrestrial electrical network, and/or the electric motor machine in current generator mode.

Other particularities and advantages will appear on reading the following description of a particular, non-limiting embodiment of the invention, made with reference to the figures in which:

: illustrates an example of a vehicle for which the method according to the invention applies.

: illustrates the main steps of a process according to the invention.

: illustrates a visual representation of a correspondence between different energy states of a battery bank and the charge states of each of these batteries, to explain a particular aspect of the invention.

It should be kept in mind that the figures are given as examples and are not limiting to the invention. They constitute schematic representations of principle intended to facilitate the understanding of the invention and are not necessarily on the scale of practical applications. Furthermore, in what follows, reference is made to all the figures taken in combination. When reference is made to one or more specific figures, these figures must be taken in combination with the other figures for the recognition of the designated numerical references. The references of unchanged elements or having the same function are common to all the figures, and the variant embodiments.

The vehicle of the understand :
- a main electrical energy storage battery BR1, called traction, rechargeable, operating under a first high direct voltage for example 350V, or between 350V and 800V,
- a BMS control means of the traction battery BR1, here integrated into the traction battery BR1, and capable for example of determining a state of charge SOC and a state of energy SOE and a state of health of the traction battery and a remaining energy capacity CSOE of the traction battery BR1 based for example on variations in the energy state SOE, this BMS control means of the traction battery BR1 comprising for example a device 102 for determining these states of charging SOC, energy SOE, health and the remaining energy capacity CSOE of the traction battery BR1.

The vehicle comprises an electrical circuit comprising for example:
- the BR1 traction battery,
- a first high voltage electrical network comprising high voltage harnesses Hc1, Hc2, H1, H2 working at the voltage of the traction battery BR1,
- an on-board charger OBC, comprising its own control means, and being coupled to the traction battery BR1 by a first high voltage charging harness Hc1,
- a current converter C1, comprising an OBCDC control means of the converter C1, and being coupled to the traction battery BR1 by a second high voltage charging beam Hc2.

This vehicle also includes:
- a second low voltage direct current electrical network comprising a low voltage harness B1,
- a secondary battery BR2, called service battery, rechargeable, operating under a second low direct voltage for example 12V, or between 12V and 48V, this secondary battery BR2 being coupled to the current converter C1 by the low voltage harness B1, this battery secondary BR2 further comprising a BECB box capable for example of determining a state of charge of the secondary battery BR2,
- electrical equipment E1 of the vehicle powered by the secondary battery BR2 via the low voltage harness B1.

This vehicle also includes:
- a first transmission chain comprising at least a first electric driving machine MM1 comprising a first inverter OD1, and providing torque to drive at least one train T1 from the energy stored in the traction battery BR1, this first driving machine MM1 being coupled to the traction battery BR1 via the first inverter OD1 by a first high voltage beam H1,
- an air conditioning compressor CLI coupled to the traction battery BR1 via the first high voltage harness H1, or another high voltage harness,
- optionally a second transmission chain comprising at least a second electric motor machine MM2 comprising a second inverter OD2, and providing torque to drive at least a second train T2 from the energy stored in the traction battery BR1, this second driving machine MM2 being coupled to the traction battery BR1 via the second inverter OD2 by a second high voltage harness H2.

The electrical circuit further comprises the first inverter OD1, the first high voltage harness H1, the second inverter OD2, the second high voltage harness H2, and the air conditioning compressor CLI.

It will also be noted that the first inverter OD1, the second inverter OD2, the air conditioning compressor CLI, the current converter C1, are capable of discharging the traction battery BR1 during a driving cycle of the vehicle, and are therefore devices consumers OD1, C1, CLI, even if all these devices can be reversible and charge, for short periods, the traction battery BR1. It will be noted that the first and second driving machine MM1, MM2 are closely linked to the first and second inverter OD1, OD2, and that they are consumer devices in the same way as the first and second inverter OD1, OD2. Conversely, the non-reversible OBC on-board charger, that is to say having only operating modes for recharging the main battery BR1, is not a consumer device because not only cannot it discharge the traction battery TR1 but recharging is done when the vehicle is stopped, that is to say outside the vehicle's driving cycle. Thus, even if this on-board charger OBC is for example reversible and allows the traction battery BR1 to be discharged through a terrestrial electrical network, it will not be considered as a consumer device within the meaning of the invention because the vehicle is at the stop.

This vehicle also includes:
- a CAN communication network,
- a DC control device, called vehicle supervision.

This CAN communication network, for example a CAN serial data bus for the English acronym “Controller Area Network” but other types of bus are possible, couples together:
- the BMS control means of the BR1 traction battery,
- the means of controlling the OBC on-board charger,
- the means of controlling the OBCDC converter,
- the BECB box,
- a first control means (not shown) of the first inverter OD1,
- a second control means (not shown) of the second inverter OD2,
- the DC control device.

So for example, the BMS control means of the traction battery BR1 transmits, via this CAN communication network, the results of the determination device 102 to any control means or device coupled to this CAN communication network, and in particular to the DC control device.

This CAN communication network is represented on the by a dotted line, while the first high-voltage electrical network and the second low-voltage electrical network are represented by a solid “bold” line.

Note that the first high voltage electrical network includes:
- the first high voltage charging beam Hc1,
- the second high voltage charging beam Hc2,
- the first high voltage beam H1,
- the second high voltage beam H2.

This high voltage beam architecture is only an example, and other architectures saving beam lengths are of course possible, such as merging the first high voltage beam H1 with the second high voltage beam H2, the underlying idea also being to have only one high voltage power output (socket) on the traction battery BR1 for example.

It should be noted that the second low-voltage electrical network includes:
- the low voltage harness B1.

This architecture of low voltage harnesses is only an example, and other architectures are of course possible, for example taking into account the fact that the vehicle includes more than a single piece of electrical equipment E1.

This second low-voltage electrical network is in particular the vehicle's on-board network, which for example supplies all the control means or DC control devices of the vehicle.

The first high voltage electrical network and the second low voltage electrical network are two networks operating respectively under the first voltage and the second voltage, these voltages being for example different as previously described, the current converter C1 adapting the voltage of a network to the other according to the direction of the desired current, in the case of a reversible converter C1 to transfer current from the secondary battery BR2 to the traction battery BR1 and vice versa. This current converter C1 is for example a direct current / direct current converter, but not necessarily. On the this converter C1 is represented outside the traction battery BR1 and the secondary battery BR2, but this is not obligatory and it can be integrated for example in the traction battery BR1, at the level of its modules or even its cells.

In what follows, we consider, by way of non-limiting example, that the vehicle is of the automobile type. This is for example a car. But the invention is not limited to this type of vehicle. It concerns in fact any type of vehicle comprising a transmission chain comprising at least one electric driving machine producing torque to drive at least one train (for example wheels). Consequently, the invention relates at least to land vehicles.

The term “electric driving machine” means, throughout the text of this document, an electric machine (or motor) arranged so as to provide or recover torque to move a vehicle, either alone or in addition. at least one possible other electric or thermal engine (such as for example a heat engine (reactor, turbojet or chemical engine)).

Here we mean electrical equipment E1, throughout the text of this document, electrical equipment powered by the low voltage network of the secondary battery BR2, this power supply being able to be done without using the current converter C1 and therefore without the help of the traction battery BR1, and which requires a greater or lesser quantity of electrical energy to operate and which can possibly ensure a safe function.

In the example illustrated non-limitingly on the , the transmission chain is of the all-electric type and can include a single MM1 electric driving machine. But the invention is not limited to this type of transmission chain. Indeed, the transmission chain could be of the hybrid type by additionally comprising a thermal engine associated with at least one train (for example the second T2), or, as illustrated, a second engine MM2.

The transmission chain here comprises, in addition to the first electric drive machine MM1, a transmission shaft and means for coupling this first drive machine to this transmission shaft. The control of at least the first electric motor machine MM1 and the coupling means is ensured by the DC control device, called vehicle supervision, via the CAN communication network. The DC control device controls the first inverter OD1 of the first driving machine MM1.

The coupling means are here responsible for coupling/decoupling the first electric motor machine MM1 to/from the transmission shaft, on order of the DC control device, in order to communicate the torque that it produces and which is defined by a setpoint (torque or speed), thanks to the electrical energy stored in the traction battery BR1, to the transmission shaft. The latter is here coupled to the first train T1 (here of wheels).

For example, the first train T1 is located at the front of the vehicle V, and preferably. But in a variant this first train T1 could be located at the rear of the vehicle.

The coupling means can, for example, be a dog mechanism or a clutch or a hydraulic torque converter or even a brake. They can take on at least two coupling states: a first (coupled) in which they ensure the coupling of the first electric drive machine MM1 to the transmission shaft and a second (decoupled) in which they decouple the first electric drive machine MM1 of the transmission shaft. Note that they can also and possibly take on at least one intermediate state (for example for clutch slippage).

In the event of the presence of the second driving machine MM2, the control of this second driving machine MM2 will be carried out, mutatis mutandis in the same way by the control device DC.

The traction battery BR1 is arranged to store electrical energy at the first voltage. It can in particular be recharged via the on-board charger OBC configured in the charging phase so as to recharge the traction battery BR1, this on-board charger OBC being coupled to the terrestrial current distribution network via for example a dedicated removable electrical cord connected to the on-board charger OBC on the one hand, and to a charging station or a power outlet from the terrestrial power distribution network.

By secondary battery, called BR2 service battery throughout the text of this document, we will understand a battery operating under the second voltage (in particular 12V) which is lower than the first voltage.

By main battery, called traction battery BR1 throughout the text of this document, we will understand a battery operating under the first voltage which is greater than the second voltage, and which supplies current to the driving machine(s) MM1, MM2. This main battery BR1 has an energy storage capacity generally much greater than the secondary battery BR2.

The OBC on-board charger is shown remote from the traction battery BR1, but this is not obligatory: it can be integrated entirely into the traction battery BR1, at the module or cell level, just like the OD1, OD2 inverters , and the converter C1.

This OBC on-board charger is for example an AC-DC rectifier converter, and can control the recharge in voltage, in current, or any other cycle including the recharge phase, a discharge phase, a relaxation phase of the battery. traction BR1.

Thus, this DC control device, by means of the CAN communication network, can in particular deactivate recharging or limit power consumed by any of the inverters OD1, OD2, the converter C1, or the on-board charger OBC.

The method according to the invention is implemented for example by means of the DC control device. But this is not obligatory, and as explained by numerous examples with reference to the , this implementation can be done by several control devices distributed in the vehicle, or partly grouped in a dedicated computer, these computers receiving the necessary data from different sensors located in the vehicle, via the CAN network for example.

These calculators are for example:
- the means of controlling the main battery BMS,
- the means of controlling the OBC on-board charger,
- the means of controlling the OBCDC converter,
- the BECB box,
- the first control means (not shown) of the first inverter OD1,
- the second control means (not shown) of the second inverter OD2,
- the DC control device.

These calculators include a possible dedicated program, for example. Consequently, a calculator or DC control device according to the invention can be produced in the form of software modules (or computer modules (or “software”)), or electronic circuits (or “hardware”), or even of a combination of electronic circuits and software modules”.

The DC control device and/or the computers comprise the means of acquisition, processing by software instructions stored in a memory as well as the control means required for the implementation of a process, in particular a process according to invention, in particular the means of controlling the main battery BMS.

The invention therefore relates to a method for determining the remaining kilometer range, at a given instant, of an electric propulsion mode of a motor vehicle.

This vehicle includes:
- the set of consumer devices OD1, OD2, C1, CLI comprising an electric driving machine MM1, MM2 capable of propelling the vehicle for the electric propulsion mode,
- the traction battery BR1 suitable for powering all consumer devices OD1, OD2, C1, CLI,
- the OBC means of recharging the traction battery BR1,
- the BMS battery controller suitable for implementing the process,
this process executing at any time steps 10 of:
- determination of the SOE energy state of the traction battery BR1,
- determination of the remaining energy capacity CSOE of the traction battery BR1,
- determination of the SOC state of charge of the traction battery BR1,
- display of the remaining 50 kilometer range of the vehicle in electric propulsion mode.

This process executes steps 20 of:
- as long as the state of charge SOC is between 100% inclusive and a first state of charge threshold SOCs1, determination of the remaining kilometer range at the given time by dividing the remaining energy capacity CSOE at the given time by a predetermined and constant CMH energy consumption per kilometer.

This first SOCs1 state of charge threshold is for example between 70 and 90% inclusive, in particular 80%.

The predetermined and constant kilometer energy consumption CMH is memorized by the battery controller and corresponds for example to a new energy capacity of the battery at a state of charge of 100%, divided by an approved kilometer range of the vehicle.

Another example of predetermined and constant kilometer energy consumption CMH corresponds for example to the smallest energy capacity when new for a state of charge of 100% among the batteries of a fleet of this battery, divided by an approved kilometer autonomy of the vehicle.

There illustrates this fleet of traction batteries and discloses a diagram corresponding to a state of energy SOE expressed in absolute terms by KWh with different states of charge SOC r, SOC u1, SOC u2 of a fleet of new batteries of the same design and outputs of the same manufacturing process. This new park here is made up of two batteries, but obviously this is a simplistic case since in reality we could envisage hundreds or even thousands of identical traction batteries. There illustrates a first battery and a second battery, for simplicity. These two batteries being of identical design, they have the same theoretical maximum energy state values SOE tmax and minimum SOE tmin, here respectively 50 KWh and 0 KWh. These are numerical examples but which are absolutely not limiting, the traction battery could for example have a theoretical maximum energy state value SOE tmax greater than 50 KWh, for example 80 or 100 KWh or more.

These two batteries each have a theoretical state of charge SOC t of which a value of 0% corresponds to the theoretical minimum energy state SOE tmin of 0KWh and a value of 100% (full charge) corresponds to the state d theoretical maximum energy SOE tmax of 50KWh. Thus, at full charge, that is to say with a theoretical state of charge SOC t at 100%, these batteries have a remaining energy capacity theoretically of 50 KWh (50 KWh – 0 KWh).

But these theoretical maximum energy state values SOE tmax and minimum SOE tmin as well as the theoretical state of charge SOC t at 100% or 0% are deliberately never reached because in this case the state of health of the battery would deteriorate significantly, or there would be an excessive temperature in one of the battery cells, or a vehicle breakdown requiring the intervention of a maintenance service or even changing the battery. This is why the BMS battery controller is configured so as to maintain the traction battery BR1 in a so-called useful state of charge, for example a first state of payload SOCu1 for the first battery, and a second state of payload SOC u2 for the second battery.

These so-called useful charge states SOCu1, SOCu2 are generally the implicit charge states used by those skilled in the art. This is for example the case in the text of this document, the state of charge SOC as well as the thresholds SOCs1, SOCs2, SOCs3 being implicitly expressed in the scale of the state of payload SOCu1, SOCu2.

Each of these payload states are expressed as a percentage between 0% and 100%, but as illustrated in the , the first payload state SOC u1 at 100% actually corresponds to the value of the theoretical state of charge SOC t strictly less than 100% and more precisely in this example equal to 97%, which also corresponds to a SOE energy state of 48.5 KWh and not the theoretical maximum energy state SOE tmax of 50 KWh. Likewise, the second payload state SOC u2 at 100% actually corresponds to the value of the theoretical state of charge SOC t strictly less than 100% and more precisely in this example equal to 92%, which also corresponds at an SOE energy state of 46.3 KWh and not at the theoretical maximum energy state SOE tmax of 50 KWh.

The same reasoning is done for the values at 0% of the first and second payload states SOC u1, SOC u2 which, for this value of 0% in fact correspond to values strictly greater than 0% of the theoretical state of charge SOC t which themselves correspond to a value of the energy state SOE of 1 KWh for the first payload state SOC u1 at 0%, and 2 KWh for the second state of charge SOC u2 at 0%.

As already explained, the remaining energy capacity CSOE of a battery at a full charge instant is the difference between the energy state SOE corresponding to a useful charge state SOCu1, SOCu2, of 100% and the state of energy corresponding to a SOCu1, SOCu2 payload state of 0%. For example, on this the new capacity of the first battery when fully charged is equal to 48.5 KWh – 1 KWh or 47.5 KWh. Likewise, the energy capacity at new full charge of the second battery is equal to 46.3 KWh – 2 KWh or 44.3 KWh. This energy capacity at new full charge is therefore different between the first battery and the second battery, due to manufacturing dispersions from one battery to another, and in particular dispersions from one battery cell to another. The new energy state values corresponding to 0% and 100% of the useful charge state are therefore specific to each battery and are predetermined by the battery manufacturer. For the determination of the average CMH approved consumption according to the invention, it is fixed and dependent only on the type of battery, the vehicle, and the autonomy of the vehicle determined during the driving cycle used during the approval of the autonomy of the vehicle, and for example the lowest remaining energy capacity when new at full charge of all the batteries manufactured for this type of vehicle. In our example of the , this remaining energy capacity when new at full charge used to determine the average CMH approved consumption will be the lower of the two batteries, namely 44.3 KWh. This is why, in this specific case, a vehicle having a traction battery BR1 with a remaining energy capacity when new at full charge greater than the smallest energy capacity when new for a state of charge of 100% among the batteries of the park of this battery, namely in our example 44.3 KWh (but strictly less than 50 KWh) will be able to have a remaining kilometer autonomy at a given moment corresponding to a full charge slightly greater than the approved autonomy. The first battery for example, falls into this possibility.

These examples of SOE state of charge values are valid for the first and second batteries when new, that is to say for a state of health of 100% and a battery reference temperature of 20°c for example . But it is clear that the remaining energy capacity at full charge of these batteries decreases with the deterioration of their state of health, just as it is also influenced by variations in battery temperature, in particular batteries comprising type cells. lithium ion. There represents new batteries, and does not represent the evolution of these capacities as a function of temperature and state of health, but these are developments well known to those skilled in the art.

This method executes at any instant a step of determining an average kilometric energy consumption achieved CMR by all the consumer devices OD1, OD2, C1, CLI, and as long as the state of charge SOC is between the first state of charge threshold SOCs1 included and a third state of charge threshold SOCs3 included strictly lower than the first state of charge threshold SOCs1, executes a step 30 of:
- determination of an average kilometer energy consumption of CMC convergence,
- determination of the remaining kilometer autonomy at the given time by dividing the remaining energy capacity CSOE at the given time by the average kilometer energy consumption of CMC convergence,
this average kilometer energy consumption of CMC convergence being such that:
- it is equal to the value of the predetermined and constant kilometric energy consumption CMH if the state of charge SOC is equal to the first state of charge threshold SOCs1,
- it is equal to the value of the average kilometric energy consumption achieved CMR if the state of charge SOC is equal to the third state of charge threshold SOCs3,
- and it evolves linearly between the value of the predetermined and constant kilometer energy consumption CMH and the value of the average kilometer energy consumption achieved CMR for each value of the state of charge SOC between the first state threshold of charge SOCs1 and the third state of charge threshold SOCs3.

This third SOCs3 state of charge threshold is for example between 40% and 60% inclusive, in particular equal to 50%.

This method determines an initial instant equal to the instant of the end of a battery recharge cycle during which the state of charge SOC reaches or exceeds a second state of charge threshold SOCs2 of the battery greater than the first state of charge threshold SOCs1, and executes at any instant a step of determining a mileage traveled KP since this initial instant, the average kilometric energy consumption achieved CMR corresponding to a cumulative energy consumption CEC of all the devices consumers OD1, OD2, C1, CLI, from the initial time to the given time, divided by the mileage traveled KP at the given time.

This second SOCs2 state of charge threshold is for example between 90% and 100% inclusive.

Another example of average kilometric energy consumption achieved CMR corresponds to a sliding average of the cumulative energy consumption CEC of all the consumer devices OD1, OD2, C1, CLI, over a predetermined mileage traveled ending at the given time , in particular a predetermined mileage traveled of 50 km.

This method executes a step 40 of determining the remaining kilometer autonomy at the given instant by dividing the SOE energy state at the given instant by the average kilometric energy consumption achieved CMR, according to one of the two examples given but this is not limiting, at the given moment, and as long as the state of charge SOC is between 0% inclusive and the third state of charge threshold SOCs3.

This process applies in particular to motor vehicles comprising:
- all of the consumer devices OD1, OD2, C1, CLI comprising an electric driving machine MM1, MM2 capable of propelling the vehicle for the electric propulsion mode,
- the traction battery BR1 suitable for powering all consumer devices OD1, OD2, C1, CLI,
- the OBC means of recharging the traction battery BR1,
- the BMS battery controller comprising the means of acquisition, processing by software instructions stored in a memory as well as the control means required to implement the method previously described.

This mode of electric propulsion is, for example, the only mode of propulsion of the vehicle.

The means of recharging the OBC battery is for example an on-board charger OBC capable of being connected to a terrestrial electrical network, and/or the electric motor machine MM1, MM2, in current generator mode.

There illustrates the main steps of the process according to the invention in the form of a very simplified flowchart and in particular:
- step 10 of determining the energy state SOE, the remaining energy capacity CSOE, and the state of charge SOC of the traction battery BR1,
- step 50 for displaying the remaining kilometer autonomy,
- step 20 of determining the remaining kilometer autonomy at the given time by dividing the remaining energy capacity CSOE at the given time by the predetermined and constant kilometer energy consumption CMH,
- step 30 of determining the average kilometer energy consumption of CMC convergence, and the remaining kilometer autonomy at the given time by dividing the remaining energy capacity CSOE at the given time by the average kilometer energy consumption of CMC convergence,
- step 40 of determining the remaining kilometer autonomy at the given time by dividing the energy state SOE at the given time by the average kilometer energy consumption achieved CMR at the given time.

It will be noted that on the the determination steps are not systematically represented by a rectangle surrounding the step number, but appear in the form of input data to a step for acquiring this data. Thus, for example, step 10 shown designates the determination of the states SOE, CSOE, SOC as well as the acquisition of these results, so as to simplify the flowchart of the method according to the invention.

Claims (10)

Method for determining the remaining kilometer range, at a given instant, of an electric propulsion mode of a motor vehicle, this vehicle comprising:
- a set of consumer devices (OD1, OD2, C1, CLI) comprising an electric motor machine (MM1, MM2) capable of propelling the vehicle for the electric propulsion mode,
- a traction battery (BR1) suitable for powering all the consumer devices (OD1, OD2, C1, CLI),
- a means of recharging (OBC) of the traction battery (BR1),
- a battery controller (BMS) suitable for implementing the process,
this process executing at any time steps (10) of:
- determination of an SOE energy state of the traction battery (BR1),
- determination of a remaining energy capacity CSOE of the traction battery (BR1)
- determination of a state of charge SOC of the traction battery (BR1),
- display of the remaining kilometer range (50) of the vehicle in electric propulsion mode,
characterized in that the method executes steps (20) of:
- as long as the state of charge SOC is between 100% inclusive and a first state of charge threshold SOCs1, determination of the remaining kilometer range at the given time by dividing the remaining energy capacity CSOE at the given time by a predetermined and constant CMH energy consumption per kilometer. Method according to claim 1, the first state of charge threshold SOCs1 being between 70 and 90% inclusive, in particular 80%. Method according to claim 1 or 2, the predetermined and constant kilometer energy consumption CMH being memorized by the battery controller and corresponding to a new energy capacity of the battery at a state of charge of 100%, divided by a kilometer autonomy approved for the vehicle. Method according to claim 1 or 2, the predetermined and constant kilometric energy consumption CMH being memorized by the battery controller and corresponding to the smallest energy capacity at new for a state of charge of 100% among the batteries of a fleet of this battery, divided by an approved kilometer range of the vehicle. Method according to one of the preceding claims executing at any time a step of determining an average energy consumption per kilometer carried out CMR by all the consumer devices (OD1, OD2, C1, CLI), and as long as the state of charge SOC is between the first state of charge threshold SOCs1 included and a third state of charge threshold SOCs3 included strictly lower than the first state of charge threshold SOCs1, executes a step (30) of:
- determination of an average kilometer energy consumption of CMC convergence,
- determination of the remaining kilometer autonomy at the given time by dividing the remaining energy capacity CSOE at the given time by the average kilometer energy consumption of convergence CMC,
this average kilometer energy consumption of CMC convergence being such that:
- it is equal to the value of the predetermined and constant kilometric energy consumption CMH if the state of charge SOC is equal to the first state of charge threshold SOCs1,
- it is equal to the value of the average kilometric energy consumption achieved CMR if the state of charge SOC is equal to the third state of charge threshold SOCs3,
- and it evolves linearly between the value of the predetermined and constant kilometer energy consumption CMH and the value of the average kilometer energy consumption achieved CMR for each value of the state of charge SOC between the first state threshold of charge SOCs1 and the third state of charge threshold SOCs3. Method according to claim 5, the third state of charge threshold SOCs3 being between 40% and 60% inclusive, in particular 50%. Method according to one of claims 5 and 6, determining an initial instant equal to the instant of the end of a battery recharge cycle during which the state of charge SOC reaches or exceeds a second state threshold of charge SOCs2 of the battery greater than the first state of charge threshold SOCs1, and executing at any instant a step of determining a mileage traveled KP since this initial instant, the average kilometric energy consumption achieved CMR corresponding to a consumption cumulative energy CEC of all consumer devices (OD1, OD2, C1, CLI), from the initial instant to the given instant, divided by the mileage traveled KP at the given instant. Method according to claim 7, the second state of charge threshold SOCs2 being between 90% and 100% inclusive. Method according to one of claims 5 and 6, the average energy consumption per kilometer achieved CMR corresponding to a sliding average of a cumulative energy consumption CEC of all the consumer devices (OD1, OD2, C1, CLI), on a predetermined mileage traveled ending at the given time, in particular 50 km. Method according to one of claims 5 to 9, executing a step (40) of determining the remaining kilometer autonomy at the given time by dividing the SOE energy state at the given time by the kilometer consumption of average energy achieved CMR at the given time as long as the state of charge SOC is between 0% inclusive and the third state of charge threshold SOCs3.