Method for diagnosing an electric-vehicle service battery and diagnostic system

Abstract

The present invention relates to a method for identifying a cause of failure of a diagnostic test of a service battery (12) of a DC voltage network of a first electric vehicle (100) implemented by a diagnostic system (1) comprising transmitting electrical parameters (D1, D2, D3) to a diagnostics-analysing first device (200), monitoring a number of successive failures of the diagnostic test, identifying a cause of the successive failures based on said transmitted electrical parameters (D1, D2, D3), generating an alert containing information on the cause of the failures detected by the diagnostics-analysing first device (200) and transmitting said alert to a second device (300) for supervising handling of malfunctions of the service battery for a set containing first and second electric vehicles.

Description

DESCRIPTION TITLE: METHOD FOR DIAGNOSING A SERVICE BATTERY OF AN ELECTRIFIED VEHICLE AND DIAGNOSTIC SYSTEM

[0001] The present invention claims priority from French application No. 2306753 filed on 06 / 28 / 2023, the content of which (text, drawings and claims) is incorporated herein by reference.

[0002] The field of the invention relates to a method for identifying a cause of a diagnostic failure of a service battery of an electrified vehicle.

[0003] Electrified vehicles, with hybrid and fully electric engines, can start while the service battery (12 volts) is in a degraded state. A degraded state means that it has difficulty maintaining a sufficient voltage level from the on-board network during significant electrical demands. Generally, for vehicles with internal combustion engines, this state of battery degradation can be detected as soon as the internal combustion engine starts.

[0004] In addition, electric vehicles include safety electrical equipment that must be powered at all times while driving. This so-called safety or priority equipment includes, for example, an electrically actuated brake system, an electric power steering system, or a trajectory control and stability system. In particular, during emergency braking or avoidance maneuvers, the service battery plays a fundamental role, as it must guarantee, in the event of failure of the electrical energy producer, generally the DCDC voltage converter, minimum voltage levels for this equipment. It is therefore necessary for safety reasons to test the service battery when starting the vehicle in order to verify with certainty its capacity to meet safety requirements.

[0005] The state of the art is known to patent application FR-A1 -3122260 describing a method for diagnosing the operating status of an electrical energy storage device for a motor vehicle which aims to avoid incorrect diagnoses made by an off-board tester. The state of the art is also known to patent application WO-A1 -2023 / 021247 describing a device for supervising tests of the battery of servitude of a vehicle configured to solicit the battery by means of one or more successive current calls, in order to evaluate electrical parameters, such as its internal resistance and its minimum voltage. The supervision device is judiciously configured to avoid situations of false test results by guaranteeing the operability of an isolation device from the electrical network. Means are also provided for estimating reliability information for a test based on the reliability level of the measured values ​​of the electrical parameters.

[0006] Despite these test reliability checks, when an alert is reported, it has been found that repair services do not always correctly identify the cause of the electrical fault. This results in the replacement of the service battery or the DCDC voltage converter when these devices are not actually the source of the electrical fault.

[0007] There is therefore a need to address the aforementioned problems. One objective of the invention is to strengthen and improve the detection of electrical faults in electrified vehicles. Another objective is to improve the operation and control of safe electrical systems. Another objective is to improve the diagnostics and operation of after-sales services for electrified vehicles.

[0008] More specifically, the invention relates to a method for identifying a cause of failure of a diagnostic test of a service battery of a direct voltage network of a first electrified vehicle implemented by a diagnostic system comprising the following steps:

[0009] - the execution of the diagnostic test of the service battery carried out by a supervisor of the first vehicle including the determination of a state parameter representative of a failure of the diagnostic test based on the electrical behavior of the service battery during the test,

[0010] - the collection of electrical parameters during each diagnosis,

[0011] the method further comprising the following steps:

[0012] - the transmission of said electrical parameters to a first diagnostic analysis equipment,

[0013] - monitoring a number of successive failures of the diagnostic test performed by the first vehicle implemented by the first diagnostic analysis equipment,

[0014] - the identification of a cause of successive failures by the first diagnostic analysis equipment from said transmitted electrical parameters,

[0015] - generating an alert comprising information on the cause of the failures detected by the first diagnostic analysis equipment and transmitting said alert to a second equipment for supervising the processing of service battery failures for a set comprising the first and second electrified vehicles.

[0016] The method according to the invention may include the following additional characteristics, alone or in combination:

[0017] - Preferably, the identification step is performed when the number of successive diagnostic failures is greater than a failure threshold, for example six successive failures.

[0018] - The diagnostic test of the service battery comprises a first diagnostic sub-step consisting of activating a consumer equipment supplied by said DC voltage network by the supervisor of the first vehicle so as to generate a current demand, a second diagnostic sub-step consisting of controlling the test during which the voltage converter supplying said DC voltage network is controlled according to a suitable voltage profile allowing the generation of a current demand to the service battery to supply the consumer equipment, and a third diagnostic sub-step consisting of determining the state of the failure parameter of the diagnostic test as a function of the electrical behavior of the service battery during the current demand,and in which said parameters transmitted during the transmission step comprise at least first parameters of the diagnostic test including at least information delivered by the supervisor, second parameters of the electrical response of the service battery and a parameter representative of the number of successive failures of the diagnostic test.,

[0019] - The step of transmitting said electrical parameters to the first diagnostic analysis equipment is implemented by means of wireless radio frequency communication through a wide area communication network to a remote server hosting said first equipment.

[0020] - Identifying the cause of failures involves a first detection sub-step consisting of monitoring a parameter representative of the voltage conversion state of the voltage converter during the diagnostic execution and reporting a converter failure based on the result of the first detection sub-step.

[0021] - - The identification of the cause of the failures includes a second detection sub-step consisting of monitoring a parameter representative of the state of the activation request of the consumer equipment during the execution of the diagnosis and reporting a failure of the supervisor of the first vehicle according to the result of the second detection sub-step.

[0022] - Identifying the cause of failures includes a third detection sub-step consisting of monitoring a parameter representative of the activation state of the consumer equipment during the execution of the diagnosis and reporting a failure of the consumer equipment based on the result of the third detection sub-step.

[0023] - The identification of the cause of the failures includes a fourth detection sub-step consisting of monitoring a parameter representative of the state of the activation request of the voltage converter controlled by the supervisor of the first vehicle during the execution of the diagnosis and signaling a failure of the supervisor according to the result of the fourth detection sub-step.

[0024] - The identification of the cause of the failures comprises a fifth detection sub-step consisting of monitoring a parameter representative of the state of the voltage converter control request generated by a converter computer to generate the voltage profile setpoint during the execution of the diagnosis and to signal a failure of the converter computer according to the result of the fifth detection sub-step and in which the identification of the cause of the failures comprises a sixth detection sub-step consisting of monitoring the voltage profile setpoint during the execution of the diagnosis and the converter voltage resulting from the setpoint and to signal a converter failure according to the result of the sixth detection sub-step.

[0025] - Identifying the cause of failures includes a seventh detection sub-step consisting of monitoring a parameter representative of the current profile of the service battery and updating the service battery parameters during the diagnostic run and reporting a failure of the service battery computer based on the result of the seventh detection sub-step.

[0026] The invention further provides a diagnostic system comprising a first electrified vehicle, a first remote diagnostic analysis device and a second device for supervising the processing of faults in the service battery for an assembly comprising the first and second electrified vehicles, in which the diagnostic system is configured to implement the method according to any one of the preceding embodiments.

[0027] The diagnostic method and system according to the invention allows for improved identification of the causes of diagnostic failures of the service battery of a set of vehicles. The invention also allows for improved analysis of diagnostic data and fault processing.

[0028] Other characteristics and advantages of the present invention will appear more clearly on reading the detailed description which follows, comprising embodiments of the invention given as non-limiting examples and illustrated by the appended drawings, in which:

[0029] [Fig.1] schematically represents a diagnostic system configured for implementing the diagnostic method according to the invention;

[0030] [Fig.2] is a functional diagram of the diagnostic method according to the invention.

[0031] Figure 1 represents an embodiment of a diagnostic system 1 configured for implementing the method according to the invention aimed at improving the identification of the causes of failure of a diagnosis of a service battery of an electrified vehicle and the processing of faults in relation to this diagnosis. In this embodiment, the system 1 comprises a first vehicle 100, a first diagnostic device 200 and a second device 300 for supervising the processing of faults of the service battery of the vehicle 100 and of a set of second vehicles.

[0032] More specifically, the vehicle 100 comprises a supervision computer 11, also designated by the term supervisor or electronic control unit, a service battery 12 coupled or controlled by a control computer 13 specific to the battery 12, a first unit 14 for analyzing data D2 from the battery 12 delivered by the control computer 13, a second unit 15 for determining the failure or success of diagnostic tests of the battery 12, a third unit 16 for counting the number of successive failures of the diagnostic test of the battery 12, a fourth unit 17 for transmitting a set of collected data including first data D1 delivered by the supervisor 11 of the vehicle 100,second data D2 delivered by the computer 13 in relation to the electrical parameters of the service battery 12 and to the electrical response of the service battery during a diagnosis and third data D3 in relation to the monitoring of failures and successes of the diagnostic tests. It should be noted that the term unit can be interpreted as a specific computer or a specific software function, and where a computer (for example the supervision computer 11) or several computers can implement one or more of said units.,

[0033] More specifically, the service battery 12 is an energy storage unit intended to supply a direct voltage network of the first vehicle 100. The service battery is of the 12 volt type. The first vehicle 100 further comprises a direct voltage network DCDC (not shown in FIG. 1) operating at a voltage of the 12 volt type intended to supply the electrical systems of the first vehicle 100, in particular the computers of the on-board electrical systems. Among these on-board electrical systems, non-priority systems are provided (for example heating systems) and so-called priority or safety systems whose voltage levels must be secured and guaranteed at all times during driving, in particular during the activation of safety braking and avoidance maneuvers. Priority systems are understood to mean in particular an electric brake system, a trajectory control system.Furthermore, the first vehicle 100 comprises a DCDC direct voltage converter (not shown in FIG. 1) responsible for converting a voltage delivered by a main energy storage system (not shown in FIG. 1) of the first vehicle 100, to a voltage level higher than the service battery 12. The main energy storage system is provided to power an electric motor of the first vehicle 100, for a voltage which may be between 48 volts. and several hundred volts, for example 350 / 450 volts or 800 / 900 volts. The main energy storage system includes, for example, lithium-ion electrochemical cells.

[0034] Furthermore, priority electrical systems must remain powered even in the event of a failure of the DCDC voltage converter supplying the direct voltage network. To this end, the service battery 12 must be regularly checked to ensure this function and maintain the minimum voltage levels for each priority system in the event of a safe operation.

[0035] Consequently, the vehicle supervision computer 11 implements a diagnostic function of the service battery 12 which operates periodically, for example at least each time the vehicle is started. This diagnostic function consists of carrying out a test of electrical demands on the direct voltage network so as to simulate the current peak demands which may be required from the service battery in the event of failure of the voltage converter or the main energy storage system during so-called safety maneuvers.

[0036] More specifically, in this preferred, but non-limiting, embodiment, the principle of the diagnostic test consists of activating an electrical energy consumer powered by the on-board network, for example a heating system comprising heating resistors, and controlling a voltage profile at the voltage converter specifically provided so that the contribution of the voltage converter is zero at a given time in order to test the capacity of the battery to respond, alone, to a current demand. The diagnostic sequence will be described in more detail in the remainder of the description of the diagnostic method.

[0037] The system 1 further comprises the first diagnostic analysis equipment 200, the main function of which, implemented by a functional unit 21, is to identify the causes of diagnostic failure and to generate an alert, implemented by a functional unit 22, containing information making it possible to inform the second equipment 300 for processing the failures of a set of second vehicles. In this preferred example, the first equipment 200 is a remote server system hosting the function 21 for identifying the causes of failures. The first equipment 200 comprises a microprocessor system and memories allowing the execution of the function of identifying and generating alerts and is suitable for the implementation implementation of a program for identifying the causes of diagnostic failures. The first equipment 200 is connected in communication on the one hand with the first vehicle 100 and on the other hand with all of the second vehicles through wireless radiofrequency communication means forming an extended communication network between one or more remote servers hosting said first equipment. The wireless communication network is for example a 4G or 5G type cellular communication network. The first equipment 200 is therefore adapted to collect information from several cooperative vehicles, said information comprising electrical parameters including at least first parameters delivered by the supervisor of these vehicles, parameters delivered by the calculator of the service battery and parameters linked to the number of successive diagnostic failures of each vehicle.

[0038] The collection and transmission unit 17 of the vehicle 100 comprises communication means adapted for the transmission of data with the equipment 200. The vehicle comprises a telematics box provided for this purpose equipped with individual connection and identification means for the use of a wireless communication network. Conventionally, the telematics box can be equipped for example with a physical or software identification card (SIM type for “Subscriber Identification Module” or eSIM for “Embedded Subscriber Identification Module”) for its connection to a wide area data network.

[0039] The implementation of the failure identification function is based on the electrical parameters D1, D2 and D3, determined first in raw format, that is to say in the form of electrical signals, analog data or digital data, then communicated by the supervisor 11, the computer 13 and the unit 16 of the vehicle 100 to the data collection and transmission unit 17. These parameters D1, D2 and D3 are processed by the unit 17 to be transmitted in the form of data suitable for transmission to the first diagnostic analysis equipment 200 through wireless radiofrequency communication means via 4G or 5G type communication for example.

[0040] The D1 parameters include information representative of the diagnostic test including information for driving the voltage profile, the voltage converter and the voltage network. More specifically, these D1 parameters include the information of a control request RQ_SQ_test of the DCDC voltage converter for the purposes of the service battery test, of a control command CMD_CTP of the consumer equipment used for the test to increase the current consumed by the DCDC voltage network, for example heating resistors, the voltage setpoint CS_DCDC sent to the DCDC voltage converter, the voltage measurement U_DCDC at the terminals of the DCDC voltage converter on the side of the 12 volt DC voltage network, the current measurement l_DCDC produced by the DCDC voltage converter to supply the DC voltage network (12 volts) and the general status ST_DCDC of the DCDC voltage converter.

[0041] The D2 parameters of the electrical response of the service battery include in particular the current I bat of the service battery 12, which by convention is measured negative in the context of a discharge of the service battery towards the DC voltage network. The D2 parameters which make it possible to determine a diagnostic failure include information representative of the value of the minimum voltage Ubat_min at the terminals of the service battery (expressed in volts), the value of the internal resistance Rint_bat (expressed in ohms) and information representative of a status of this data ST_Rint making it possible to know the level of reliability of the previous information provided during the diagnostic test so as to know whether it can be used to characterize the state of the service battery.

[0042] The D3 parameters include at least one piece of information representing a failure and the number of successive failures CPT_Dg_Diagnostic test failure.

[0043] The units 14, 15 and 16 have the function of implementing the diagnosis and counting the number of successive failures of diagnostic tests. More precisely, the unit 14 has the function of analyzing the parameters D2 received from the computer 13 of the service battery 12. These parameters are transmitted via an on-board wired communication bus, for example of the CAN (“Control Area Network”) type. The unit 14 delivers to the unit 15 data D2 comprising information representative of the internal resistance Rint_bat and the minimum voltage Ubat_min of the service battery during a diagnostic test.

[0044] More specifically, unit 14 at each current demand of the diagnostic test must update the internal resistance information Rint_bat and the minimum voltage Ubat_min. Furthermore, unit 14 receives from computer 13 the reliability information ST_Rint associated with this data to estimate a reliability level of this data.

[0045] Unit 15 is configured to determine whether the diagnostic test has been executed or not, or whether its execution has not allowed the internal resistance information Rint_bat, the minimum voltage Ubat_min and the reliability information ST_Rint associated with this data to be updated. If the diagnostic has not been executed or if the information D2 has not been updated following a test then this unit detects that the diagnostic has failed. Unit 15 delivers a signal Dg_Echec informing of the detection of a failure.

[0046] Furthermore, the unit 16 is configured to count the number of successive failures of a diagnosis of the service battery from the signal Dg_Echec over a period comprising several driving cycles, i.e. several cycles of starting and stopping the vehicle. This function implements a counter incrementing a variable upon each failure detection. This function thus makes it possible to detect and identify a persistent failure of the service battery. The unit 16 delivers a signal CPT_Dg_Echec to the unit 17 thus making it possible to inform the equipment 200 to identify the causes of the failures using all the data D1 and D2 which were also collected during the execution of a diagnostic test. The unit 17 is configured to transmit information D3 representative of the total number of failures during the use of the vehicle and / or the number of successive failures of the diagnostic tests.

[0047] Furthermore, the first diagnostic analysis equipment 200 comprises a unit 21 for identifying the cause of the diagnostic failures from the data received D1, D2 and D3 by the first vehicle and the second vehicles. The identification unit implements an identification function for each collaborative vehicle and delivers information representative of the cause of the diagnostic failures of a service battery. A unit 22 is responsible for generating an alert identifying the possible cause and transmitting it to the second equipment 300 for supervising the processing of the failures of the service battery of a set of second electrified vehicles.

[0048] The second equipment may be a server or server system providing a fault monitoring service for a repair shop network or a vehicle after-sales service network. The second equipment is connected in data communication with the first equipment, typically by an internet-type computer network or a proprietary network which may be wireless radio frequency. or wired. This second equipment 300 makes it possible to inform after-sales services of the causes of failure affecting the first vehicle specifically or the causes of a set of second vehicles in order to improve the handling of breakdowns.

[0049] In Figure 2, the method for identifying a cause of diagnostic failure according to the invention is represented in the form of a functional block diagram. This method is implemented by a diagnostic system as described in Figure 1.

[0050] In a first step E1, the method comprises the execution of a diagnosis of the service battery by an electric motor vehicle. This diagnosis is triggered periodically, for example at each start or at each driving cycle of a vehicle. In this preferred example, the supervision computer of a vehicle detects the start and this computer verifies that the DCDC voltage converter of the vehicle between a high voltage network supplied by the main storage system and a low voltage network to which the service battery is connected is active and capable of carrying out the voltage conversion.

[0051] Then, according to the diagnostic method, a first sub-step, controlled by the supervision computer, consists of activating a consumer equipment supplied by the direct voltage network (12 volts) by the vehicle supervisor so as to generate a current demand, for example a request generating an additional current requirement of approximately 40 amps, for example, compared to the consumption prior to the activation of the consumer equipment. This consumer equipment is for example an electric resistance heating system.

[0052] During the first step E1, the method further comprises a second diagnostic sub-step consisting of controlling a test during which the voltage converter is controlled according to a suitable voltage profile allowing the generation of a current demand to the service battery to supply the consumer equipment. The calculator of the DCDC converter is responsible, in response to this profile, for converting this profile into a voltage setpoint evolving between a first high value (for example 13.1 volts) allowing a supply of the 12 volt direct voltage network only by the converter (the contribution of the service battery is then zero) and a second low value (for example 10.6 volts) which aims to reduce to 0 amperes the contribution of the DCDC voltage converter to the supply of the 12 volt direct voltage network (the contribution of the 12 volt service battery to the supply of the direct voltage network being then total). Thus, during the execution of the voltage profile, the current supplied by the service battery varies dynamically between 0 amperes and the value of the total current requested by the voltage network.

[0053] During the first step E1, the method further comprises a third diagnostic sub-step consisting of determining the value of the electrical parameters of the internal resistance Rint_bat, of the minimum voltage Ubat_min measured reached at the time of each current demand. This third sub-step is implemented by the analysis unit 14. During this third sub-step, the method further comprises determining the capacity of the service battery to respond to each current demand and the state of the failure parameter Dg_echec of the diagnostic test as a function of the electrical behavior of the service battery during the current demand, in particular from the state of the reliability signal and the updating of the minimum voltage and internal resistance values.

[0054] More precisely, the analysis unit determines three cases. In the first case, the reliability information considers that the internal resistance Rint_bat and minimum voltage Ubat min information are not reliable, which triggers the detection of a failure. In the second case, the reliability information considers that the information is reliable. The internal resistance Rint_bat and minimum voltage Ubat_min parameters are then updated. In the third case, the reliability information considers that the information is reliable, however it is detected that the internal resistance Rint_bat and minimum voltage Ubat_min parameters remain frozen during the current demand of the service battery. This situation consequently triggers the detection of a diagnostic test failure.

[0055] Then, the method comprises a step E2 of collecting the electrical parameters D1, D2 and D3 during each diagnosis. The collection is implemented through the on-board communication bus for processing the data allowing their transmission to the first diagnostic analysis equipment 200. The collection is implemented for example by a vehicle computer intended to centralize data and information.

[0056] Then, the method comprises a step E3 of transmitting said electrical parameters D1, D2 and D3 to the first diagnostic analysis equipment 200. In this preferred embodiment, the first equipment 200 is hosted on a server remote in order to centralize data from several vehicles in order to implement monitoring and fault processing globally across all of the car manufacturer's vehicles. The E3 transmission is therefore implemented by wireless radio frequency communication means through a wide area communication network, such as 4G or 5G, or by satellite communication for example, to this remote server hosting the first equipment 200. In most cases, this E3 transmission is carried out in a situation of normal use of the vehicle, for example at the driver's home, when starting or when the vehicle is being recharged.

[0057] However, the possibility is not ruled out that the diagnostic analysis function 21 and the alert generation function 22 including information on the cause of the failures may one and / or the other be hosted on an on-board computer of a vehicle.

[0058] Then, in accordance with the invention, the method comprises a step E4 of monitoring the number of successive failures of the diagnostic test performed by the first vehicle. This step E4 is implemented by the first diagnostic analysis equipment 200. More precisely, monitoring E4 consists of comparing the number of successive failures with a predetermined failure threshold, for example six successive failures. As soon as the threshold is exceeded, first of all an alert is generated at the level of a computer of the first vehicle via a warning light for example, so that the driver has his vehicle checked. The electrical power supply system of the 12 volt DC network is an essential and safety function, it is therefore necessary to alert the teams monitoring and handling the breakdown and firstly by the owner of the vehicle concerned.

[0059] Furthermore, in the case of the invention, the method provides that in the event of detection that the number of failures is greater than this failure threshold, the method comprises a step E5 of identifying a cause of the successive failures by the first diagnostic analysis equipment 200 from said transmitted electrical parameters D1, D2 and D3. This makes it possible to ensure a global analysis of all the vehicles in an automated manner in order to prevent a systematic risk on a large scale.

[0060] This identification step E5 provides for several failure cases that can be specifically detected by the detection sub-steps described in more detail below. allowing for deeper diagnosis and identification of the vehicle system that may have caused the repeated failures. At least seven failure cases are planned.

[0061] During the E5 identification, a first detection sub-step consists of monitoring the parameter ST_DCDC, among the parameters D1, representative of the voltage conversion state of the voltage converter during the execution of the diagnosis. In case of detection that the state of the voltage converter is not in voltage conversion operation then the first sub-step signals a failure of the converter by means of a signal or data comprising information identifying the voltage converter as being the cause of the failure specifically, for example via a specific alert code.

[0062] During the identification E5, a second detection sub-step consists of monitoring a parameter of the CMD_CTP request, among the parameters D1, representative of the state of the request for activation of the consumer equipment during the execution of the diagnosis. In the event of detection that the CMD_CTP request was not issued by the supervision computer of the first vehicle, then the second sub-step comprises the signaling of a failure of the vehicle supervisor by means of a signal or data comprising information identifying the supervision computer as being the cause of the failure specifically, for example via a specific alert code.

[0063] During the identification E5, a third detection sub-step consists of monitoring a parameter, among the data D1 or D2, representative of the activation state of the consumer equipment during the execution of the diagnosis, for example an activation state parameter of the consumer equipment, the value of the currents of the network l_DCDC or of the service battery l_bat. In the event of detection that the consumer equipment is not activated, the third sub-step comprises the signaling of a failure of the consumer equipment by means of a signal or data comprising information identifying the consumer equipment as being the cause of the failure specifically, for example via a specific alert code.

[0064] During the identification E5, a fourth detection sub-step consists of monitoring a parameter, among the data D1, representative of the state of the activation request of the voltage converter RQ_SQ_test controlled by the supervisor of the first vehicle during the execution of the diagnosis. In the event of detection that the supervision computer does not issue the request, the fourth sub-step comprises the reporting a supervisor failure by means of a signal or data including information identifying the supervisory computer as being the cause of the failure specifically, for example via a specific alert code.

[0065] During the E5 identification, a fifth detection sub-step consists of monitoring the RQ_SQ_test parameter representative of the state of the voltage converter control request generated by a converter computer to generate the voltage profile setpoint CS_DCDC during the execution of the diagnosis and if this computer generates the resulting voltage profile setpoint. In the event of detection, that the request is issued but that the CS_DCDC setpoint is not controlled, then this fifth sub-step signals a failure of the converter computer by means of a signal or data comprising information identifying the converter computer as being the cause of the failure specifically, for example via a specific alert code.

[0066] During the E5 identification, a sixth detection sub-step consists of monitoring the setpoint of the voltage profile CS_DCDC during the execution of the diagnosis and the converter voltage U DCDC resulting from the setpoint. In case of detection that the converter does not control the voltage U_DCDC, then the sixth sub-step comprises the signaling of a converter failure by means of a signal or data comprising information identifying the converter as being the cause of the failure specifically, for example via a specific alert code.

[0067] Finally, during the E5 identification, a seventh detection sub-step consists of monitoring the parameter representative of the current profile of the service battery l_bat and updating the parameters of the service battery during the execution of the diagnosis. In the event of detection that the characteristic electrical parameters of the battery are not updated, the seventh sub-step comprises the signaling of a failure of the service battery computer by means of a signal or data comprising information identifying the service battery computer as being the cause of the failure specifically, for example via a specific alert code.

[0068] Finally, the invention comprises a step E6 of generating an alert from the signals and data generated during the identification step E6 comprising information on the cause of the failures. The alert is transmitted from the first equipment 200 to the second equipment 300 for supervising the processing of the failures. of the service battery of a set of second electrified vehicles. This sharing of information makes it possible to centralize diagnostics by a service whose purpose is to improve the management of electrical system developments and repairs. This makes it possible to avoid replacing the battery in the event of a failure of other equipment involved during the diagnostic process. This alert explicitly indicates the cause of the failure, for example via a code or informative data.

[0069] In a variant of the method, it is envisaged that the step of identifying the cause of a failure can be executed before the failure threshold is reached. The causes of failures can be recorded in the memory of the first device 200 in order to keep a history of the causes of the failures.

[0070] The invention provides one or more computers equipped with memories for recording programs comprising instructions which, when the programs are executed, lead them to implement the method for identifying the causes of failure of a diagnostic test of a service battery according to the invention. The computers and programs are distributed in the diagnostic system among the vehicle systems, platforms and remote servers according to the desired choice of hardware architecture. The computers and memories are equipped with integrated circuits and may be of the FPGA (Field Programmable Gate Array), DSP (Digital Signal Processor), ASIC (Application Specific Integrated Circuit) type, for example.

[0071] The invention is described in the above by way of example. It is understood that the person skilled in the art is able to produce different variant embodiments of the invention by associating, for example, the different characteristics above taken alone or in combination, without departing from the scope of the invention.

Claims

CLAIMS 1. Method for identifying a cause of failure of a diagnostic test of a service battery (12) of a direct voltage network of a first electrified vehicle (100) implemented by a diagnostic system (1) comprising the following steps: - the execution (E1) of the diagnostic test of the service battery (12) carried out by a supervisor (11) of the first vehicle (100) comprising the determination of a state parameter representative of a failure (Dg_Failure) of the diagnostic test as a function of the electrical behavior of the service battery (12) during the test, - the collection (E2) of electrical parameters (D1, D2, D3) during each diagnosis, the method being characterized in that it comprises the following steps: - the transmission (E3) of said electrical parameters (D1, D2, D3) to a first diagnostic analysis equipment (200), - monitoring (E4) a number of successive failures of the diagnostic test performed by the first vehicle (100) implemented by the first diagnostic analysis equipment (200), - the identification (E5) of a cause of the successive failures by the first diagnostic analysis equipment (200) from said transmitted electrical parameters (D1, D2, D3), - the generation (E6) of an alert comprising information on the cause of the failures detected by the first diagnostic analysis equipment (200) and the transmission (E6) of said alert to a second equipment (300) for supervising the processing of faults in the service battery for an assembly comprising the first and second electrified vehicles.

2. Method according to claim 1 in which the diagnostic test of the service battery (12) comprises: - a first diagnostic sub-step consisting of activating consumer equipment supplied by said direct voltage network by the supervisor (11) of the first vehicle (100) so as to generate a current demand, - a second diagnostic sub-step consisting of controlling the test during which the voltage converter supplying said direct voltage network is controlled according to a suitable voltage profile allowing the generation of a current demand to the service battery (12) to power the consumer equipment, - and a third diagnostic sub-step consisting of determining the state of the failure parameter (Dg_echec) of the diagnostic test as a function of the electrical behavior of the service battery (12) during the current demand, and in which said parameters (D1, D2, D3) transmitted during the transmission step (E3) comprise at least first parameters (D1) of the diagnostic test including at least information delivered by the supervisor (11), second parameters (D2) of the electrical response of the service battery (12) and a parameter (D3) representative of the number of successive failures (CPT_Dg_Echec) of the diagnostic test.

3. Method according to claim 2, wherein the step of transmitting (E3) said electrical parameters (D1, D2, D3) to the first diagnostic analysis equipment (200) is implemented by wireless radiofrequency communication means through a wide area communication network to a remote server hosting said first equipment.

4. Method according to claim 2 or 3, in which the identification (E5) of the cause of the failures comprises a first detection sub-step consisting of monitoring a parameter representative of the voltage conversion state of the voltage converter during the execution of the diagnosis and signaling a failure of the converter according to the result of the first detection sub-step.

5. Method according to any one of claims 2 to 4, in which the identification (E5) of the cause of the failures comprises a second detection sub-step consisting of monitoring a parameter representative of the state of the activation request of the consumer equipment during the execution of the diagnosis and signaling a failure of the supervisor (11) of the first vehicle (100) according to the result of the second detection sub-step.

6. Method according to any one of claims 2 to 5, in which the identification (E5) of the cause of the failures comprises a third detection sub-step consisting of monitoring a parameter representative of the activation state of the consumer equipment during the execution of the diagnosis and signaling a failure of the consumer equipment depending on the result of the third detection sub-step.

7. Method according to any one of claims 2 to 6, in which the identification (E5) of the cause of the failures comprises a fourth detection sub-step consisting of monitoring a parameter representative of the state of the activation request of the voltage converter controlled by the supervisor (11) of the first vehicle (100) during the execution of the diagnosis and signaling a failure of the supervisor (11) according to the result of the fourth detection sub-step.

8. Method according to any one of claims 2 to 7, in which the identification (E5) of the cause of the failures comprises a fifth detection sub-step consisting of monitoring a parameter representative of the state of the voltage converter control request generated by a converter computer to generate the voltage profile setpoint during the execution of the diagnosis and to signal a failure of the converter computer according to the result of the fifth detection sub-step and in which the identification of the cause of the failures comprises a sixth detection sub-step consisting of monitoring the voltage profile setpoint during the execution of the diagnosis and the converter voltage resulting from the setpoint and to signal a converter failure according to the result of the sixth detection sub-step.

9. Method according to any one of claims 1 to 8, in which the identification (E5) of the cause of the failures comprises a seventh detection sub-step consisting of monitoring a parameter representative of the current profile of the service battery (12) and updating the parameters of the service battery during the execution of the diagnosis and signaling a failure of the calculator of the service battery according to the result of the seventh detection sub-step.

10. Diagnostic system (1) comprising a first electrified vehicle (100), a first remote diagnostic analysis equipment (200) and a second equipment for supervising the processing of faults (300) of the service battery for an assembly comprising the first (100) and second electrified vehicles, characterized in that the diagnostic system (1) is configured for implementing the method according to any one of claims 1 to 9.

Images