MONITORING THE CONDITION OF AN AUXILIARY BATTERY IN AN ELECTRIC POWERTRAIN VEHICLE, THROUGH SAFETY TESTS

Abstract

A monitoring device (DS) is fitted to a vehicle (V) comprising an electric powertrain and an on-board electrical system (RB) supplied with electrical energy by a power unit including a service battery (BS) and at least one electric power generator (GE). This device (DS) includes a processor (PR) and memory that performs operations consisting, when the electric powertrain is activated, of triggering a current draw selected by the on-board electrical system (RB) via the electric power generator (GE) and then via the service battery (BS), in order to determine a minimum voltage across the terminals of the service battery (BS) and its internal resistance, and then to determine the state of the service battery (BS) based on these determined minimum voltage and internal resistance. Figure 1

Description

Description Title of the invention: MONITORING THE STATE OF A VEHICLE SERVICE BATTERY WITH GMP ELECTRICAL, BY SAFETY TESTS Technical field of the invention

[0001] = The invention relates to vehicles with an electric powertrain (or powertrain), and more specifically the monitoring of the condition of the auxiliary battery of such vehicles. State of the art

[0002] As those skilled in the art know, certain vehicles include a motorcycle- propulsion system (or powertrain) and an onboard electrical network powered by a generator power supply including a rechargeable service battery and at least one generator Electrical energy generators coupled together (directly or indirectly). By For example, this electrical power generator can be an alternator or an alterno- starter when the powertrain includes at least one internal combustion engine, or a converter, of the direct current / direct current (or DC / DC) type, and associated to a main battery of the low, medium or high voltage type, when the GMP includes at least one electric motor.

[0003] — In what follows and precedes, the term “service battery” means a battery rechargeable by at least one electrical power generator and of a very low type voltage (typically 12 V, 24 V or 48 V).

[0004] — Furthermore, in what follows and precedes, the term “onboard network” means a electrical power supply network including electrical equipment (or components) (or electronic) consuming electrical energy and being "non-priority" for at least one of them and "safe" (and therefore priority) for at minus one other one of them.

[0005] = Dec plus, in what follows and what precedes it, the term "equipment (or organc)" means safety" – equipment (or component) ensuring at least one so-called function "Safe" because it concerns the safety of vehicle passengers, and therefore which must be supplied with electrical energy as a priority. This is the case, by for example, electric power steering or an electric braking system (service brake, emergency brake, braking assistance system or traction control, by example).

[0006] In certain situations during the life of a vehicle, such as for example during emergency maneuvers (such as emergency braking or evasive maneuvers), it It is essential that the security bodies participating in these maneuvers be powered with a level of electrical power that guarantees their operation, as well as their expected performance level. The vehicle's power supply unit is responsible for providing this level of electrical power to the relevant safety-critical components at any given time. It should be noted that this power supply unit is also responsible for simultaneously providing the electrical power level required for the operation of other non-safety-critical components in use at any given time. In the event that the power supply unit is unable to provide the necessary electrical power to all the electrical components concerned at the time in question, a voltage collapse could occur at the terminals of the on-board network and therefore of the safety electrical components, which would not allow the latter to function correctly (i.e. with a sufficient level of performance), and therefore could endanger the passengers of the vehicle and / or the vehicle itself and / or people located in the vicinity of this vehicle. When a vehicle has both an auxiliary battery and a main battery (supplying electrical power to at least one electric drive unit), the main battery is primarily used to power the vehicle's electrical system. The auxiliary battery provides electrical power to start any internal combustion engine and provides supplemental power to prevent the electrical system from collapsing in the event of a high transient energy consumption. Consequently, in a vehicle with at least a partially internal combustion engine, if the auxiliary battery is degraded or undercharged, the internal combustion engine cannot be started, which alerts the driver.However, in a purely electric powertrain vehicle, the auxiliary battery may have the required power level (not very high) to power computers (necessary for starting the vehicle), but this power level may be insufficient to ensure safe electrical power supply requirements, thus posing a risk to the vehicle's passengers. In patent document EP-A1 1207083, it was proposed to determine whether the auxiliary battery capacity falls below a threshold chosen to at least meet the electrical power requirements of an electric power steering or electric braking system, and if so, to trigger a limitation on the vehicle's maximum speed. However, this does not allow for determining the actual state of the auxiliary battery. Furthermore, it does not allow for informing the driver of a potential risk. Moreover, if the capacity measurement is unreliable, the speed limitation may be unjustified or an insufficient measure in the presence of a safety risk. The invention therefore aims, in particular, to determine the actual state of the battery of Servicing of a purely electric powertrain vehicle, through safety tests. Presentation of the invention In particular, it proposes for this purpose a monitoring device intended to equip a vehicle comprising an electric powertrain and an on-board network supplied with electrical energy by a power unit comprising a rechargeable auxiliary battery and at least one electrical energy generator. This monitoring device is characterized by the fact that it includes at least one processor and at least one memory arranged to perform the operations consisting, in the event of the start-up of the electric powertrain, of triggering a current consumption chosen by the on-board network via the electric power generator and then via the auxiliary battery, at least once, in order to determine a minimum voltage across the terminals of the auxiliary battery and an internal resistance of the latter, and then to determine a state of the auxiliary battery as a function of these minimum voltage and internal resistance determined. Thus, we have the real state of the auxiliary battery just before the vehicle starts moving, which is particularly reassuring for its passengers. The monitoring device according to the invention may include other features which may be taken separately or in combination, and in particular: - its processor and memory can be arranged to perform the operations of triggering a current consumption chosen by the on-board network via the electrical power generator and then via the service battery, at least twice in succession for a first chosen duration, in order to determine each time a minimum voltage across the terminals of the service battery and an internal resistance of the latter, then to determine an average minimum voltage from these determined minimum voltages and an average internal resistance from these determined internal resistances, then the state of the service battery as a function of these determined average minimum voltage and average internal resistance; - in the presence of the last option, its processor and memory can be arranged to perform the operations of triggering a current consumption by the on-board network via the electrical power generator for a second chosen duration, after each current consumption chosen by the on-board network via the auxiliary battery during the first chosen duration, except for a final current consumption chosen by the on-board network via the auxiliary battery; - its processor and memory can be arranged to perform the operations of triggering the chosen current consumption by the on-board network via the electrical power generator for a third chosen duration following a other current consumption, not triggered, by the on-board network via the electrical power generator for a fourth chosen duration; - its processor and memory can be arranged to perform the operations of triggering each current consumption chosen by the on-board network via the auxiliary battery by triggering a chosen voltage reduction of the electrical power generator for a time interval between 1 ms and 8 ms: - its processor and memory can be arranged to perform the operations of determining each minimum voltage and each internal resistance when a current coming out of the service battery increases by a value greater than a first threshold for a configurable duration starting at the same time as a first chosen duration begins; - its processor and its memory can be arranged to perform the operations of determining the state in a group comprising a first state representing an impossibility of ensuring an electrical supply to the on-board network adapted to the electrical supply needs of at least a partial electrical component, a second state representing an uncertainty of the ability to ensure an electrical supply to the on-board network adapted to the electrical supply needs of at least a partial electrical component, and a third state representing an ability to ensure an electrical supply to the on-board network adapted to the electrical supply needs of at least a partial electrical component; - in the presence of the last option, its processor and memory can be arranged to perform the operations consisting, in the event of determination of the first state, of triggering at least one alert for a passenger of the vehicle chosen from among an alert of risk incurred and an alert recommending at least one action to be taken, and in the event of determination of the second state, of triggering a service alert for that passenger; - its processor and memory can be arranged to perform operations consisting of determining the state based also on reliability information; - in the presence of the last option, its processor and memory can be arranged to perform the operations of determining the state when the reliability information of the (is) is representative of a certain reliability. The invention also proposes a vehicle, possibly of the automobile type, comprising an electric powertrain, an on-board network supplied with electrical energy by a power unit comprising a rechargeable auxiliary battery and at least one electrical energy generator, as well as a monitoring device of the type presented above. The invention also proposes a monitoring method intended to be implemented in a vehicle comprising an electric powertrain and an on-board network supplied with electrical energy by a power unit comprising a rechargeable auxiliary battery and at least one electrical power generator. This monitoring process is characterized by the fact that it includes a step in which, in the event of the electric powertrain being started, a current consumption chosen by the on-board network is triggered via the electric power generator and then via the auxiliary battery, at least once, in order to determine a minimum voltage across the terminals of the auxiliary battery and an internal resistance of the latter, then a state of the auxiliary battery is determined as a function of these minimum voltage and internal resistance determined. The invention also proposes a computer program product comprising a set of instructions which, when executed by processing means, is suitable for implementing a monitoring method of the type presented above to monitor the state of a rechargeable auxiliary battery of a vehicle comprising an electric powertrain and an on-board network supplied with electrical energy by a power unit comprising this auxiliary battery and at least one electrical energy generator. Brief description of the figures Other features and advantages of the invention will become apparent upon examination of the detailed description below, and the accompanying drawings, in which: [fig.1] schematically and functionally illustrates an example of the embodiment of a vehicle comprising a purely electric powertrain and a distribution box including a monitoring device according to the invention, [Fig. 2] schematically and functionally illustrates an example of an implementation of a power distribution monitoring computer, including an example of a monitoring device according to the invention, and [fig.3] schematically illustrates an example of an algorithm implementing a monitoring method according to the invention. Detailed description of the invention The invention aims in particular to provide a DS monitoring device, and an associated monitoring method, intended to enable the monitoring, by safety tests, of the state of a rechargeable BS auxiliary battery of a vehicle V with a purely electric powertrain (or PWM). In what follows, vehicle V is considered, by way of non-limiting example, to be an automobile. For example, it could be a car, as illustrated in [Fig. 1]. However, the invention is not limited to this type of vehicle. It relates to any A vehicle type comprising an electric powertrain and an on-board electrical system supplied by a power unit including a rechargeable auxiliary battery and at least one electric power generator. Thus, it concerns, for example, land vehicles (commercial vehicles, motorhomes, minibuses, coaches, trucks, motorcycles, road maintenance vehicles, construction vehicles, agricultural vehicles, recreational vehicles (snowmobiles, go-karts), and tracked vehicles, for example), boats, and aircraft. Figure 1 schematically represents a vehicle V comprising an electric GMP transmission chain, an on-board network RB, a service battery BS, an electric power generator GE and a monitoring device DS according to the invention. The RB on-board network is an electrical power supply network that includes electrical (or electronic) equipment (or components) that consume electrical energy. At least one of these electrical (or electronic) equipment (or components) is "non-priority" and at least one other of these electrical (or electronic) equipment (or components) is "safety" (and therefore priority). It should be noted that the term "safety equipment (or component)" here refers to equipment (or component) that consumes electrical energy to perform at least one safety-related function (because it concerns the safety of the vehicle's passengers), and therefore must be given priority in terms of electrical power supply. Examples include electric power steering or an electric braking system (service brake, emergency brake, braking assistance system, or traction control system, for example). Non-priority electrical (or electronic) equipment (or component) consumes electrical energy to perform at least one function that is not essential, such as heating / air conditioning or seat heating or seat massage device. The auxiliary battery BS is responsible for supplying electrical power to the vehicle's electrical system RB, supplementing that supplied by the main battery BP described later. For example, this auxiliary battery BS can be configured as a very low voltage type battery (typically 12 V, 24 V, or 48 V). It is rechargeable by an electrical power generator GE from the vehicle V. The transmission chain has a purely electric GMP and therefore includes, in particular, an electric MM driving machine, an AM drive shaft, a BP main battery and an AT transmission shaft. Here, "electric motive machine" means an electric machine arranged to provide or recover torque to move vehicle V. The drive unit MM (here an electric motor) is coupled to the battery The main battery (BP) is supplied with electrical energy, and may also supply this main battery (BP) with electrical energy. It is coupled to the drive shaft (AM) to provide it with torque through rotation. This drive shaft (AM) is coupled to a reduction gear (RD), which is also coupled to the transmission shaft (AT). The transmission shaft is itself coupled to a first set of wheels (T1), preferably via a differential (DI). This first train T1 is located here in the front part PV of the vehicle V. But in a variant this first train T1 could be the one which is here referenced T2 and which is located in the rear part PR of the vehicle V. For example, the main BP battery can be of the low voltage type (typically 400 V as an illustration). But it could also be of the medium voltage or high voltage type. The MM driving machine is also coupled to the GE electric power generator which is also coupled (here indirectly) to the BS auxiliary battery, notably to recharge it with electrical energy from the main BP battery and converted. This GE electrical power generator is a DC / DC converter, for example. Besides charging the service battery BS, it is also responsible for supplying the onboard electrical system RB with converted power from the main battery BP. It should also be noted that in the example illustrated (non-exhaustively) in [Fig. 1], the vehicle V includes a distribution box BD to which the auxiliary battery BS, the electric power generator GE, and the on-board electrical network RB are connected. This distribution box BD is responsible for distributing the electrical energy stored in the auxiliary battery BS or produced by the electric power generator GE to the on-board electrical network RB to power the electrical components (or equipment) according to received power demands. The distribution of this electrical energy can be monitored by a control unit CS. In the example illustrated (non-exhaustively) in [Fig. 1], the monitoring control unit CS is part of the distribution box BD. However, in an alternative embodiment (not shown), the monitoring control unit CS might not be part of the distribution box BD. As illustrated non-limitingly in [fig.2], a DS monitoring device, according to the invention, comprises at least one PR processor and at least one MD memory which are arranged to perform operations at least during each start-up of the electric powertrain. These operations consist, firstly, in the event of the electric powertrain being activated, of triggering a current consumption chosen by the on-board network RB, initially via the electric power generator GE, then via the service battery BS, at least once, in order to determine a minimum voltage um across the terminals of the service battery BS and an internal resistance rm of the latter (BS). These operations then consist of determining a state of the service battery BS as a function of this determined minimum voltage um and this determined internal resistance rm. It will be understood that each triggering of a chosen current consumption ccc by the on-board network RB, via the electrical power generator GE and then via the service battery BS, at least once, constitutes a safety test of the service battery BS. This provides the current state of the auxiliary battery (BS) just before the vehicle (V) starts moving. This is particularly reassuring when the auxiliary battery (BS) is in a degraded or low-charged state, which would prevent it from meeting the vehicle's safe electrical power requirements. It should be noted that in the example illustrated (though not exhaustively) in Figures 1 and 2, the PR processor and MD memory are part of the CS supervisory control unit, which is implemented as a combination of electrical or electronic circuits or components (or "hardware") and software modules (or "software"). However, in an alternative embodiment (not shown), the PR processor and MD memory could be part of a control unit that is not the CS supervisory control unit and therefore performs at least one other function within the vehicle (V). Such a control unit could be external to the distribution box (BD). In another alternative embodiment (not shown), the DS monitoring device could include its own control unit, notably comprising its PR processor and MD memory. In this case, it could be part of the distribution box (BD) or external to it (BD). The PR processor can, for example, be a digital signal processor (DSP). This PR processor can comprise integrated circuits (or printed circuit boards), or several integrated circuits (or printed circuit boards) connected by wired or wireless connections. An integrated circuit (or printed circuit board) is defined as any type of device capable of performing at least one electrical or electronic operation. Thus, it could, for example, be a microcontroller. The MD memory is random access in order to store instructions for the implementation by the PR processor of at least part of the monitoring process described later (and therefore of its functionalities). It should be noted that the PR processor and the MD memory can also be arranged to perform the operations of triggering a chosen current consumption ccc by the on-board network RB via the electrical power generator GE and then via the service battery BS, at least twice in succession for a first chosen duration d1, in order to determine each time the minimum voltage umk across the terminals of the service battery BS and its internal resistance rmk (BS). In this case, the PR processor and the MD memory are also arranged to perform the operations of determining the average minimum voltage um from these determined minimum voltages umk and the average internal resistance rm from these determined internal resistances rmk, and then determining the state of the service battery BS as a function of these determined average minimum voltage um and average internal resistance rm. The determinations of the minimum voltage umk and internal resistance rmk can, for example, be performed after the expiration of a configurable time following the onset (or beginning) of the variation (il — i2) of the current leaving the service battery BS (the voltage dynamics are lower than the current dynamics). For example, this configurable time can be chosen to be 5 ms. Preferably, each determination of an internal resistance rmk is performed immediately after the expiration of the configurable time, while each determination of a minimum voltage umk is performed after the expiration of a time interval beginning immediately after the expiration of the configurable time and having a duration strictly less than dl, and for example equal to 100 ms.In this case, the internal resistance rmk is determined immediately after the end of the variation (il - i2) of the current leaving the service battery BS (i.e., 5 ms or 6 ms after the start of this variation) and the minimum voltage umk is determined 100 ms after the end of the variation (il - i2) of the current leaving the service battery BS (i.e., 105 ms after the start of this variation). Each minimum voltage um can be determined by a first electronic circuit coupled to the service battery BS. Furthermore, each internal resistance rmk can be deduced from the variation of the voltage (ul — u2) during the variation of the current (il — 12) and from this variation of the current (il — i2) determined by a second electronic circuit (rmk = (ul — u2) / (i1 — i2)). For example, the number of times a selected current consumption is triggered by the onboard network RB via the electrical power generator GE and then via the service battery BS for a safety test could be three. However, this number can be any value greater than or equal to one. Thus, this number could be one, two, four, or five, for example. For example, the PR processor and MD memory can also be configured to perform operations involving triggering a current draw from the onboard network RB via the electrical power generator GE for a second, chosen duration d2, after each chosen current draw ccc from the onboard network RB via the service battery BS during the first, chosen duration d1, except for a final, chosen current draw ccc from the onboard network RB via the electrical power generator GE. In other words, in a safety testmultiple on-board current consumption is triggered by the on-board network RB via the electric power generator GE (possibly for a second duration d2 chosen), then the on-board network RB via the service battery BS is triggered for a first duration d1 chosen, then a on-board network RB via the electric power generator GE is triggered for a second duration d2 chosen, then the on-board network RB via the service battery BS is triggered again for another first duration d1 chosen, then a on-board network RB via the electric power generator GE is triggered for another second duration d2 chosen,and so on until the very last activation of the selected current consumption (ccc) by the on-board network (RB) via the auxiliary battery (BS), after which the safety test ends. For example, each first duration d1 can be between 100 ms and 300 ms, and each second duration d2 can be between 100 ms and 300 ms. Thus, we can, for example, choose first dl and second d2 durations of equal 200 ms. But d1 and d2 can have different values. It should also be noted that the PR processor and the MD memory can also be arranged to perform the operations of triggering the very first selected current consumption ccc by the on-board network RB via the electrical power generator GE for a third selected duration d3 which follows another untriggered current consumption cend by the on-board network RB via the electrical power generator GE for a fourth selected duration d4, and which precedes the very first selected current consumption ccc by the on-board network RB via the service battery BS for a first selected duration dl. Here, "untriggered current consumption" refers to normal current consumption by the vehicle's electrical system (RB) via the electrical power generator (GE) when the engine starts (without intervention from the monitoring device DS). Therefore, during a safety test, each selected current consumption (ccc) is strictly greater than the untriggered (normal) current consumption (cend). For example, during a safety test, each selected current consumption (cec) can exceed 50 A. Thus, it can, for example, be approximately 60 A. Each selected current consumption (ccc) can be achieved, for instance, by activating heating elements fitted to the vehicle (V) (and possibly of the PTC type ("Positive Temperature Coefficient"). The two phases, having the third d3 and fourth d4 durations and preceding the very first current consumption chosen ccc by the on-board network RB via the service battery BS, can together constitute an initial preparatory phase. Each a phase having a first duration dl chosen can constitute a diagnostic phase, and each phase having a second duration d2 chosen can constitute a new preparatory phase carried out between two successive diagnostic phases of the safety test. This initial preparatory phase (with a configurable duration of (d4+d3)) allows for the management of situations involving the polarization of the auxiliary battery BS, for example, when the latter (BS) has previously been subjected to a high voltage (e.g., > 14 V) for a relatively long period (this can notably be the case during a charging phase of the vehicle V preceding a safety test). This minimizes inaccuracies in the determinations of the internal resistances rm (or rmk) when the auxiliary battery BS is not in a stable (or rested) state, which regularly occurs between two driving phases. For example, the third duration d3 can be equal to the second duration d2. Also, for example, the fourth duration d4 can be between 1 s and 3 s. Thus, we can, for example, choose a fourth duration d4 equal to 2.8 s. It should also be noted that the PR processor and MD memory can also be configured to perform operations consisting of triggering each selected current consumption ccc by the on-board network RB via the service battery BS by triggering a selected voltage reduction rt of the electrical power generator GE for a time interval it between 1 ms and 8 ms. For example, the time interval it is the configurable duration, and in this case it can be equal to 5 ms. It is understandable that when the voltage setpoint of the electrical power generator (EPG) is reduced, for example in less than 5 ms, the voltage of the EPG suddenly becomes lower (within the limits of voltage drops) than the actual voltage of the auxiliary battery (BS). Since the latter (BS) is connected to the onboard electrical system (RB), it will therefore have to supply the latter (RB) with the current that was previously supplied by the electrical power generator (GE). This results in a change in the current leaving the auxiliary battery (BS) that is all the more rapid as the change in the setpoint of the electrical power generator (GE) is rapid. For example, in the case of an RB 12 V on-board network, the voltage setpoint value of the electrical power generator GE can be reduced to a value of about 10.6 V instead of about 13.1 V in a preparatory phase (initial or not). It should also be noted that the PR processor and the MD memory can also be arranged to perform the operations of determining each minimum voltage and each internal resistance when the current exiting the service battery BS increases by a value that is greater than a first threshold sl during the configurable duration (for example, equal to 5 ms) which begins at the same time as a first duration d1 chosen. At the end of the safety test, and therefore after the last selected current draw (ccc) by the onboard network (RB) via the service battery (BS), current consumption by the onboard network (RB) resumes via the electrical power generator (GE) in an untriggered and therefore normal (ccnd) manner. This is achieved by imposing a normal (or unreduced) voltage setpoint on the electrical power generator (GE). It should also be noted that the PR processor and the MD memory can also be arranged to perform operations consisting of determining the state of the BS service battery in a group of three predefined states: - a first state el may represent an inability of the auxiliary battery BS to provide an electrical supply to the on-board network RB adapted to the electrical supply needs, at least partial, of at least one safety-critical electrical component, - a second state e2 may represent an uncertainty in the capacity of the auxiliary battery BS to ensure a power supply to the on-board network RB adapted to the power supply needs, at least partial, of at least one safety-critical electrical component, and - a third state e3 can be representative of a capacity of the service battery BS to ensure an electrical supply of the on-board network RB adapted to the electrical supply needs of at least a partial electrical component of at least one safety electrical component. It is understood that when the auxiliary battery (BS) is in the first state, it cannot provide the additional electrical energy needed to meet the safe power requirements of vehicle V, which is dangerous. Conversely, when the auxiliary battery (BS) is in the third state (e3), it can provide the additional electrical energy needed to meet the safe power requirements of vehicle V. Finally, when the auxiliary battery (BS) is in the second state (e2), there is a non-zero probability that it cannot provide the additional electrical energy needed to meet the safe power requirements of vehicle V, which is potentially dangerous. To determine the state of the service battery BS, the monitoring device DS can, for example, use a state map of the service battery BS based on its average internal resistance rm (in milliohms or ohms) and its average minimum voltage um (in volts). The digital data defining this map are stored in memory MD or in mass storage MM, which will be discussed later. But instead of using a map to determine the state of the BS service battery, one or more mathematical formulas could be used. In the event of determination of the first state el, the PR processor and the MD memory can also be arranged to perform the operations of triggering at least one first alert of a passenger of the vehicle V which is chosen from an alert of risk incurred and an alert recommending at least one action to be taken. This initial passenger alert is designed to draw the passenger's attention to a problem with the auxiliary battery (BS) that requires immediate repair at an authorized service center. This initial alert may be triggered by the display of a dedicated service indicator (e.g., the auxiliary battery indicator), possibly in red, and / or a dedicated service indicator (e.g., the stop indicator), also possibly in red, or by a dedicated text-based warning message on a vehicle display (V), such as the instrument panel or central instrument cluster, and / or by the broadcast of a dedicated audible (or audio) warning message via at least one speaker in the vehicle. The display of this initial alert should ideally remain visible until the end of the vehicle's driving phase. If the second state e2 is determined, the PR processor and MD memory can also be arranged to perform the operations of triggering a second service alert for the passenger. This second alert is solely intended to draw the passenger's attention to a potential problem, prompting them to schedule a service appointment for a vehicle inspection. This alert can be triggered by the general (non-dedicated) service indicator light, possibly in orange, or by a dedicated text warning message on a vehicle display, such as the instrument panel or central instrument cluster, and / or by a dedicated audible (or audio) warning message played through at least one speaker in the vehicle. The second alert should ideally remain displayed until the vehicle has finished driving. It should also be noted that the PR processor and MD memory can also be configured to perform operations involving determining the state of the BS service battery, taking into account reliability information. It is understandable that such information enhances the value of knowing the current state of the BS service battery, as it guarantees that this state accurately reflects reality. Reliability information can, for example, be chosen from at least: - initial information indicative of a lack of reliability, because the re- Internal resistances and minimum voltages are considered unreliable due to their abnormal values ​​or abnormal variation. - a second piece of information if2 representing an impossibility of carrying out the determinations of the internal resistances rm (or rmk) and minimum voltages (um (or umk), - a third piece of information if3 representing an uncertainty regarding the possibility of completing the safety test fully, for example due to suboptimal conditions for success or an interruption of the safety test required by a computer in vehicle V (possibly CS), and - a fourth piece of information if4 representative of a certain reliability, because the internal resistances rm (or rmk) and minimum voltages um (or umk) are considered reliable because of their normal values. For example, an internal resistance rmk (or rm) can be considered to have a normal variation when the current output from the service battery BS has fallen below a predefined current value (e.g., -50 A) as a function of ccc, and this output current has varied (il - i2) by a value greater than the predefined current value for a configurable duration (e.g., 5 ms), or when the minimum voltage umk (or um) is strictly greater than a predefined voltage value (e.g., 11 V) after a voltage change greater than a predefined value (e.g., 1 V). In all other cases, the internal resistance rmk (or rm) is considered to have an abnormal variation. It should also be noted, as illustrated non-limitingly on [fig.2], that the CS computer (or the possible computer of the DS monitoring device) can also include, in addition to the MD RAM and PR processor, a mass memory MM, in particular for the storage of the minimum voltages um (or umk) determined, the currents imk determined, the internal resistances rm (or rmk) determined, and any digital mapping data, and intermediate data involved in all its calculations and processing.Furthermore, this computer CD may also include an input interface IE for receiving at least the determined minimum voltages um (or umk), the determined currents imk, and the messages signaling the activation of the electrical GMP for use in calculations or processing, possibly after shaping and / or demodulating and / or amplifying them, in a manner known per se, by means of a digital signal processor PR. In addition, this computer CS (or the possible computer of the DS monitoring device) may also include an output interface IS, in particular for delivering the alert commands and trigger orders determined by the DS monitoring device. The invention can also be considered in the form of a monitoring method intended to be implemented in the vehicle V described above in order to enable the monitoring of monitoring the condition of its BS service battery. This monitoring process includes a step 10-70 in which, in the event of the electric GMP being started, a selected current consumption ccc is triggered by the on-board network RB via the electric power generator GE and then via the service battery BS, at least once, in order to determine a minimum voltage um across the terminals of the service battery BS and an internal resistance rm of the latter (BS), then a state of the service battery BS is determined as a function of these minimum voltage um and internal resistance rm determined. Figure 3 schematically illustrates an example of an algorithm implementing a 10-70 monitoring method according to the invention. The algorithm includes a sub-step 10 which begins when the DS monitoring device is informed of the start-up of the electric GMP and in which an initial preparatory phase begins. Then, after the expiry of the fourth duration d4 (during which the on-board network RB consumes current normally (cend) via the electrical power generator GE), a chosen current consumption ccc is triggered in a substep 20 by the on-board network RB via the electrical power generator GE for a third duration d3 (for example equal to d2). Then, after the expiry of the third duration d3 (and therefore at the end of the initial preparatory phase), a diagnostic phase is started in a sub-step 30 by triggering a chosen current consumption ccc by the on-board network RB via the service battery BS for a first chosen duration d1, in order to determine a minimum voltage umk across the terminals of the service battery BS and an internal resistance rmk of the latter (BS). Then, in a sub-step 40, the value vc of a diagnostic phase counter (initially set to zero during sub-step 10) is incremented by one unit. Then, in a substep 50, we determine if the value vc of the diagnostic phase counter is equal to a second threshold s2 (for example, equal to three). If negative (vc < s2), we return to perform substep 20. Conversely, if the condition is yes (vc = s2), a minimum average voltage um is determined in substep 60 from the minimum voltages umk determined (at each iteration), and an average internal resistance rm is determined from the internal resistances rmk determined (at each iteration). Then, in substep 70, a state of the auxiliary battery BS is determined as a function of the determined minimum average voltage um and average internal resistance rm. The measures to be taken can then be decided based on the determined state. It should also be noted that the invention also proposes a computer program product (or computer program) comprising a set of instructions which, when executed by electronic circuit (or hardware) processing means, such as the PR processor, is suitable for implementing the monitoring process described above to monitor the status of the vehicle V's BS auxiliary battery.

Claims

Demands

1. Monitoring device (MD) for a vehicle (V) comprising a electric powertrain and an on-board network (RB) powered by electrical power from a power supply unit including a battery rechargeable service battery (SBM) and at least one power generator electrical (GE), characterized in that it comprises at least one processor (PR) and at least one memory (MD) arranged to perform the operations consisting, in the event of the commissioning of said electric powertrain, to trigger a consumption of current chosen by said on-board network (RB) via said generator of electrical energy (GE) and then via said service battery (BS), to at least once, in order to determine a minimum voltage across the terminals of said service battery (SB) and an internal resistance of this last (BS), then to determine a state of said service battery (BS) depending on these minimum voltage and internal resistance de- finished.

2. Device according to claim 1, characterized in that said processor (PR) and said memory (MD) are arranged to perform the operations consisting of triggering a current consumption chosen by the said on-board network (RB) via said electrical power generator (GE) then via said service battery (SB), at least twice in succession during an initial chosen duration, in order to determine a tension each time minimum at the terminals of said service battery (BS) and a re- internal resistance of the latter (BS), then to determine a voltage minimum average from the said determined minimum voltages and an average internal resistance based on said internal resistances de- completed, then said state of the service battery (SB) according to these average minimum voltage and average internal resistance of- finished.

3. Device according to claim 2, characterized in that said processor (PR) and said memory (MD) are arranged to perform the operations consisting of triggering current consumption by said network of board (RB) via said electrical power generator (GE) during a second chosen duration, after each chosen electricity consumption by said on-board network (RB) via said service battery (BS) during the said first chosen period, except for a final current consumption chosen by said on-board network (RB) via said service battery (BS).

4. Device according to any one of claims 1 to 3, characterized in that said processor (PR) and said memory (MD) are arranged to to perform the operations consisting of triggering said consumption current chosen by said on-board network (RB) via said generator electrical energy (GE) for a third chosen duration making following another, untriggered, current consumption by the said on-board network (RB) via said electrical power generator (GE) for a fourth chosen duration.

5. Device according to any one of claims 1 to 4, characterized in that said processor (PR) and said memory (MD) are arranged to perform the operations involved in triggering each consumption of current chosen by said on-board network {RB) via said battery of servitude (BS) by triggering a chosen voltage reduction of said ge- electrical energy generator (GE) during a time interval between 1 ms and 8 ms.

6. Device according to any one of claims 1 to 5, characterized in that said processor (PR) and said memory (MD) are arranged to perform the operations consisting of determining each minimum voltage and each internal resistance when a current flows out of said battery easement (BS) increases by a value greater than a first threshold for a configurable duration, starting at the same time as begins an initial chosen duration.

7. Device according to any one of claims 1 to 6, characterized in that said processor (PR) and said memory (MD) are arranged to perform the operations consisting of determining said state in a group including a first state representing an impossibility to ensure an electrical power supply for said on-board network (RB) adapted to at least partial power supply needs of at least one safe electrical component, of a second state representative of an in- certainty of the ability to ensure an electrical supply to said network on-board (RB) adapted to electrical power requirements at least partial failure of at least one safety electrical component, and of a third state representative of a capacity to ensure an electrical supply said on-board network (RB) adapted to power supply needs electrical at least partial of at least one electrical component curative.

8. Vehicle (V) comprising an electric powertrain and a on-board network (RB) powered by electrical energy from a generator power supply including a rechargeable service battery (BS) and at least one electrical power generator (EPG), characterized in that that it also includes a monitoring device (MD) according to one of previous claims.

9. A monitoring method for a vehicle (V) comprising a group electric powertrain and an on-board network (RB) powered by electrical power from a power supply unit including a battery rechargeable service battery (SBM) and at least one power generator electrical (GE), characterized in that it comprises a (10-70) stage in which, in the event of the operation of said powertrain electrical, a current consumption chosen by the said is triggered on-board network (RB) via said electrical power generator (GE) then via said service battery (SB), at least once, in order to de- to achieve a minimum voltage across the terminals of said service battery (BS) and an internal resistance of the latter (BS), then we determine a state of said service battery (SB) as a function of these voltages minimum and internal resistance determined.

10. Product computer program comprising a set of instructions which, when executed by processing means, is capable of putting implement the monitoring method according to claim 9 for monitor the condition of a rechargeable service battery (SB) of a vehicle (V) comprising an electric powertrain and a on-board network (RB) powered by electrical energy from a generator power supply including said service battery (SB) and at an electric power generator (EPG).