Method and device for carrying out a charging process of an electrically driven vehicle
Patent Information
- Application Number
- EP2025712913
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-05-21
- Filing Date
- 2025-03-14
- Publication Date
- 2026-01-07
AI Technical Summary
The challenge of ensuring reliable charging processes for electric vehicles amidst unpredictable energy supply fluctuations, particularly during external control interventions, which can lead to insufficient charging due to data bus system sleep states or authentication losses, compromising vehicle readiness for subsequent journeys.
A method and device utilizing an external computing unit to monitor charging processes, transmit wake-up signals to the vehicle data bus system, and adjust charging currents to ensure the energy storage system is sufficiently charged, even after interruptions, by maintaining an active data bus state and re-authenticating if necessary.
Enhances the robustness of charging processes, ensuring the vehicle's energy storage system is fully charged before use, thereby increasing vehicle availability and contributing to market success and environmental sustainability.
Smart Images
Figure EP2025057092_27112025_PF_FP_ABST
Abstract
Description
[0001] Method and device for carrying out a charging process of an electrically powered vehicle
[0002] The invention relates to a method for carrying out a charging process of an electrically powered vehicle.
[0003] The invention further relates to a device for carrying out a charging process of an electrically powered vehicle.
[0004] US Patent 2013 / 0015814 A1 discloses a system and a method for notifying a vehicle user. Notification occurs when an electric vehicle charging process is unexpectedly interrupted. The system monitors the connection between the electric vehicle and an external charging device and issues a command to a notification system to send the notification to the vehicle user when an interruption is detected.
[0005] The object of the present invention is to provide a novel method and a novel device for carrying out a charging process of an electrically powered vehicle.
[0006] The problem is solved according to the invention by a method which has the features specified in claim 1 and by a device which has the features specified in claim 10.
[0007] Advantageous embodiments of the invention are the subject of the dependent claims.
[0008] In the method for carrying out a charging process of an electrically powered vehicle, it is provided according to the invention that
[0009] - a charging process of an electrical energy storage device of the vehicle, carried out at an energy source, is monitored by means of a vehicle-external computing unit that is or can be coupled to the vehicle in terms of data processing, and - in the event of an interruption of the charging process detected by the computing unit, a wake-up signal is transmitted by the computing unit to a vehicle data bus system required for the execution of the charging process and / or
[0010] - after a resumption of the charging process following an interruption or a temporary reduction of the charging current by the energy source, the processing unit checks whether the vehicle-side charging current is limited to a value that is lower than the maximum charging current that can be provided by the energy source, and if a limitation exists, the vehicle-side limited value of the charging current is increased depending on the time remaining until the end of the charging process and / or a target state of charge of the energy storage.
[0011] Due to the increasing use of renewable energies for energy supply and their weather dependency, increased fluctuations in the energy supply, meaning a surplus or shortage of electrical energy, can occur. To compensate for these fluctuations, flexible, controllable electrical loads, such as charging electric vehicles, can be used. In situations with a shortage of electrical energy, the active charging process of an electric vehicle can be temporarily interrupted, for example, for a period of two hours, by means of an external control intervention at the energy source. For this purpose, the energy source, such as a wallbox or a public charging station, reduces the available charging current to zero at the beginning of the control intervention and returns it to the maximum available value after the intervention ends.The vehicle then interrupts the charging process for the duration of the control intervention and should resume it afterward. Depending on the duration of the control intervention and the vehicle's configuration, interrupting the active charging process results in a state in which the vehicle data bus system required for executing the charging process is put into a sleep state, also known as data bus sleep. This sleep state prevents the vehicle's energy storage system from being correctly recharged after the control intervention ends. Consequently, the energy storage system does not continue charging after the control intervention, meaning that the energy storage system's charge level may be insufficient when a vehicle user wants to begin their journey.
[0012] The vehicle data bus system is understood to be a data processing unit in which several devices, for example control units, are coupled to each other by means of at least one data bus line and communicate via this data bus line.
[0013] Due to the monitoring of the charging process by the vehicle's external computing unit, the present method enables particularly reliable transmission of the wake-up signal to the vehicle data bus system required for executing the charging process. This increases the robustness of charging processes with external control interventions by reducing the probability that the charging process will not resume correctly after such intervention. Consequently, the risk of the vehicle's energy storage system being insufficiently charged before the start of a subsequent journey is reduced. This, in turn, results in increased vehicle availability and thus improved mobility for vehicle users.By increasing the robustness of the charging process, vehicle availability, and user mobility, successful market penetration of electric vehicles can be achieved, making a significant contribution to climate and environmental protection as well as to the business success of vehicle manufacturers. The process also enables robust external control interventions, necessary to ensure a stable energy supply.
[0014] Furthermore, it is possible that after an interruption of a charging process or a temporary reduction in charging current by an energy source, a maximum charging current preset at the beginning of the charging process (e.g., by selecting a specific charging program) may not be sufficient to charge the energy storage device to the desired state of charge within the remaining time until the end of the charging process. Because the processing unit checks whether the vehicle has limited the charging current to a value below the maximum charging current available from the energy source, and increases the vehicle-limited charging current, the method ensures that the vehicle's energy storage device is sufficiently charged even in such situations before the start of a subsequent journey.
[0015] In one possible embodiment of the method, a signal is transmitted as a wake-up signal to maintain an active state of the vehicle data bus system. This reliably prevents the vehicle data bus system from entering a sleep state. Thus, a charging process can be restarted particularly quickly and reliably after an interruption and termination of the control intervention. In another possible embodiment of the method, the signal is transmitted to the vehicle data bus system at regular intervals, for example, every five minutes. For instance, the time interval is chosen to be shorter than the time after which the vehicle data bus system enters a sleep state following an interruption of the charging process. This enables particularly reliable prevention of the vehicle data bus system entering a sleep state during an interruption of the charging process.
[0016] In another possible embodiment of the method, when the processing unit detects a sleep state of the vehicle data bus system resulting from an interruption of the charging process, an activation signal is transmitted to the vehicle data bus system as a wake-up signal. This enables the vehicle data bus system to be activated or "woken up" from its sleep state, so that a charging process can be restarted particularly quickly and reliably after an interruption and termination of the control intervention.
[0017] In another possible embodiment of the procedure, if the processing unit detects a loss of vehicle authentication at the energy source resulting from an interruption of the charging process, it transmits a request signal to the vehicle and / or the energy source for re-authentication. Such a loss of authentication can occur, for example, if the vehicle's charging time at the energy source has expired due to a duration of control intervention and the associated interruption of the charging process. By transmitting the request signal for re-authentication, the charging process of the energy storage system can be reliably resumed after the interruption and loss of authentication.
[0018] In another possible embodiment of the procedure, it is envisaged that the monitoring of the charging process includes
[0019] - the processing unit can query the target charging current and the actual charging current from the vehicle and / or the energy source,
[0020] - the vehicle and / or energy source transmit the target and actual charging current values to the processing unit, - the processing unit compares the target and actual charging current values and
[0021] - the charging process is interrupted by the processing unit when the actual charging current is zero and / or
[0022] - the vehicle-side limitation of the charging current is detected by means of the processing unit if the actual charging current is lower than the maximum charging current that can be provided by the energy source.
[0023] Monitoring the target charging current and the actual charging current can be carried out in a particularly simple and reliable manner with minimal hardware requirements.
[0024] In another possible embodiment of the process, the data connection between the vehicle and the computing unit is established via a mobile network. This enables reliable data transmission between the vehicle and the computing unit.
[0025] In another possible embodiment of the method, the wake-up signal is transmitted to the vehicle via the mobile network as a short message using a short message service (SMS). Since a vehicle's telecommunications module that connects to the mobile network is generally permanently activated, even during periods of data bus inactivity, transmitting the wake-up signal as a short message via SMS to the telecommunications module ensures particularly reliable transmission and reception of the wake-up signal.
[0026] In another possible embodiment of the process, a cloud server or backend server is used as the central computing unit. Such servers enable reliable and effective monitoring of the charging process and execution of the process from outside the vehicle.
[0027] The device for carrying out a charging process of an electrically powered vehicle is characterized according to the invention in that
[0028] - the vehicle can be connected or is connected to an external computing unit in terms of data technology and
[0029] - the computing unit is trained,
[0030] - to monitor a charging process of the vehicle's electrical energy storage device being carried out at an energy source and - in the event of an interruption of the charging process detected by the processing unit, to transmit a wake-up signal to a vehicle data bus system required for the execution of the charging process and / or
[0031] - after resuming the charging process following an interruption or a temporary reduction in charging current by the energy source, to check whether the vehicle-side charging current is limited to a value lower than the maximum charging current available from the energy source, and if a limitation exists, to increase the vehicle-side limited value of the charging current depending on the time remaining until the end of the charging process and / or a target state of charge of the energy storage device.
[0032] Due to the monitoring of the charging process by the vehicle's external processing unit, the present device enables particularly reliable transmission of the wake-up signal to the vehicle data bus system required for executing the charging process. This increases the robustness of charging processes with external control interventions by reducing the probability that the charging process will not resume correctly after such intervention. Consequently, the risk of the vehicle's energy storage system being insufficiently charged before the start of a subsequent journey is reduced. This, in turn, results in increased vehicle availability and thus improved mobility for vehicle users.By increasing the robustness of the charging process, vehicle availability, and user mobility, successful market penetration of electric vehicles can be achieved, making a significant contribution to climate and environmental protection as well as to the business success of vehicle manufacturers. The method also enables robust external control interventions, necessary to ensure a stable energy supply. By checking, via the processing unit, whether the vehicle's charging current is limited to a value below the maximum charging current available from the energy source, and by increasing this vehicle-side limit, the device ensures that the vehicle's energy storage system is sufficiently charged even in such situations before the start of a subsequent journey.
[0033] Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. These show:
[0034] Fig. 1 schematically shows a charging current profile, a charging state profile of an electrical energy storage device and a charging state during a charging process according to the prior art.
[0035] Fig. 2 schematically shows a device for carrying out a charging process of an electrically powered vehicle and a power network and
[0036] Fig. 3 schematically shows a course of a charging current, a course of a state of charge of an electrical energy storage device and a state of charge during a charging process carried out by means of the device according to Figure 2.
[0037] Corresponding parts are marked with the same reference symbols in all figures.
[0038] Figure 1 shows a charging current I as a function of time t, a state of charge (SOC) as a function of time t, and a charging status LS as a function of time t during a charging process of an electrical energy storage device 1, shown in more detail in Figure 2, of an electrically powered vehicle 1, also shown in more detail in Figure 2, according to the prior art. The charging status LS can, in this case, have the states "charging cable not connected LK", "interruption of charging process UL", "end of charging process EL", and "charging C".
[0039] To charge the energy storage device 1, it is electrically coupled to an energy source 3, for example a public charging station or a wallbox, which is shown in more detail in Figure 2 and provides electrical energy for charging the energy storage device 1.
[0040] In certain situations, for example, in the event of a shortage of electrical energy in an electrical power grid 4 coupled to the energy source 3 and also shown in Figure 2, an active charging process of the energy storage device 1 can be temporarily interrupted by means of an external control intervention SE. In this case, the energy source 3 sets the available charging current I to zero at the beginning of the control intervention SE and returns it to its maximum available value after the end of the control intervention SE. The vehicle 2 then interrupts the charging process for the duration of the control intervention SE and should resume it after the end of the control intervention SE. Depending on the duration of the control intervention SE and the configuration of the vehicle 2, the interruption of the active charging process results in a state in which a vehicle data bus system required for executing the charging process is put into a sleep state.This standby state prevents energy storage device 1 from being correctly recharged after the end of the control intervention SE. As a result, energy storage device 1 is not charged further after the control intervention SE, so that the state of charge (SOC) of energy storage device 1 may be insufficient when a vehicle user wants to start their journey.
[0041] This is illustrated by the time profiles of the charging current I, the state of charge SOC and the charging status LS.
[0042] After the charging process starts (ST), the energy storage device 1 is electrically charged by the charging current I in charging status LS "Charging C", thus increasing its state of charge (SOC). During the external control intervention SE, charging is interrupted in charging status LS "Interruption of charging process UL" by setting the charging current I to zero. The state of charge (SOC) remains essentially constant during this interruption. After the end of the control intervention SE, the charging process is not resumed due to the vehicle data bus system's sleep state. Therefore, at the end of the charging process (EL), in charging statuses LS "End of charging process EL" and "Charging cable not connected LK", the state of charge (SOC) remains unchanged after disconnecting the charging cable 8 from the energy source 3 and may be insufficient for subsequent tasks of the vehicle 2.
[0043] Figure 2 shows a possible embodiment of a device 5 for carrying out a charging process of an energy storage device 1 of an electrically powered vehicle 2 and an electrical power grid 4. Figure 3 shows a possible course of a charging current I as a function of time t, a possible course of a state of charge (SOC) of the electrical energy storage device 1 as a function of time t, and a state of charge (LS) during a charging process of the electrical energy storage device 1 carried out by means of the device 5 according to Figure 2.
[0044] The energy network 4 can be a public energy network 4 or a local energy network 4, for example, a house's electrical network. The device 5 comprises the energy source 3 electrically coupled to the energy network 5, for example, a public charging station or a wallbox, an external computing unit 6, and at least one application unit 7.
[0045] Computing unit 6 is, for example, a cloud server or a backend server.
[0046] Vehicle 2 is wirelessly connected to the computing unit 6 via a mobile network MN, for example.
[0047] Furthermore, the vehicle 2 is connected to the energy source 3 by means of a charging cable 8 for the purpose of charging the energy storage device 1. The vehicle 2, the charging cable 8, and the energy source 3 are specifically designed such that the vehicle 2 can communicate with the energy source 3 via the charging cable 8.
[0048] As already explained in the description of Figure 1, external control interventions SE of the power grid 4 can lead to an interruption of the charging process UL of the energy storage device 1. Such a control intervention SE can, for example, be a so-called grid-supporting control intervention SE to compensate for a shortage of electrical energy in a public power grid 4. The control intervention SE can also be a control intervention SE of the house network, for example, to interrupt the charging process in the event of a shortage of surplus electrical energy generated from solar power.
[0049] As already explained in the description of Figure 1, interruptions to the charging process caused by the control intervention SE can lead to a standstill state of a vehicle data bus system required for the execution of the charging process.
[0050] For example, the following errors can occur after an interruption of the charging process:
[0051] Error scenario 1:
[0052] After the end of the control intervention SE, energy source 3 provides a maximum available charging current I, for example, 32 A. Vehicle 2 resumes charging, but not with the maximum available charging current I, but rather with a reduced charging current I of, for example, 20 A. This can result, for instance, from a charging program, such as an ECO charging program, being selected at the start of the charging process, which limits the maximum charging current I. This leads to the risk that the time t available after the interruption of the charging process UL is no longer sufficient to charge the energy storage device 1 to a desired state of charge (SOC). This error can also occur if the charging process is not interrupted, but the charging current I is temporarily reduced.
[0053] Error scenario 2:
[0054] Due to the duration of the control intervention SE and the associated interruption of the charging process UL, the vehicle data bus system is put into a sleep state to conserve energy. This state is also referred to as the "sleep state" of vehicle 2. If, after the end of the control intervention SE, the energy source 3 now specifies a maximum available charging current I greater than 0 A, the vehicle 2, which is in a sleep state, cannot react to this and does not resume charging, but remains in the interrupted charging process UL.
[0055] Error scenario 3:
[0056] Due to the duration of the control intervention SE and the associated interruption of the charging process UL, the charging time or session of vehicle 2 at energy source 3, for which vehicle 2 was authenticated at energy source 3 (e.g., via a charging card to allocate an energy quantity and payment information), has expired. After the end of the control intervention SE, vehicle 2 is no longer authorized by energy source 3 to draw charging current I from it. An internal logic of energy source 3 now prevents a maximum available charging current I greater than 0 A from being specified. Accordingly, vehicle 2 does not resume charging.
[0057] The described fault conditions can also occur in combination. For example, the vehicle data bus system can enter sleep mode (fault condition 2) and also lose authentication with the energy source 3 (fault condition 3). As a consequence of these fault conditions, a desired target state of charge of, for example, 100% SOC for a vehicle user may not be reached at the time when they intend to start their next journey. To prevent the failure to resume the charging process or charging with insufficient charging current I (fault condition 1) after an interruption of the charging process UL caused by an external control intervention SE, as illustrated in Figure 1 and described by the fault conditions described above, the charging process is monitored by the processing unit 6.
[0058] If the processing unit 6 detects an interruption of the charging process UL, it sends a wake-up signal AS to the vehicle data bus system required for executing the charging process, so that it is not put into sleep mode or is reactivated or "woken up" from it. The wake-up signal AS is transmitted to the vehicle 2, in particular via a mobile data network of the mobile network MN, whereby the processing unit 6 establishes communication with the vehicle 2 via the mobile network MN and can send messages to the vehicle 2 using, for example, standard communication protocols such as HTTPS.Should such communication via the mobile data network of the MN network not be possible due to the vehicle data bus system being in standby mode, one possible configuration provides for the wake-up signal AS to be transmitted to vehicle 2 as a short message via a short message service (SMS) over the MN mobile network. Since a telecommunications module of vehicle 2 that connects to the MN mobile network is generally permanently activated, even during periods of data bus standby, transmitting the wake-up signal AS as a short message via the short message service to the telecommunications module ensures particularly reliable transmission and reception of the wake-up signal AS.
[0059] The processing unit 6 detects the interruption of the charging process UL, in particular by monitoring the charging current I, whereby
[0060] - using the computing unit 6 in a query A, a target charging current and an actual charging current from vehicle 2 and / or energy source 3 are queried,
[0061] - by means of the vehicle 2 and / or the energy source 3, values of the target charging current and the actual charging current are transmitted to the computing unit 6 in one transmission,
[0062] - the values of the target charging current and the actual charging current are compared using the processing unit 6 and
[0063] - The charging process UL is interrupted by the processing unit 6 when the actual charging current is zero. Furthermore, the processing unit 6 detects the vehicle-side limitation of the charging current I (error case 1) when the actual charging current is less than the maximum charging current I that can be provided by the energy source 3.
[0064] For the error cases described above, the charging process is carried out using device 5 as described below:
[0065] For error case 1:
[0066] During the monitoring of the charging process by the processing unit 6, the actual charging current is recorded by the processing unit 6 after the end of the control intervention SE, which led to the interruption of the charging process UL and / or a temporary reduction of the charging current I. If a deviation from the maximum available charging current I is detected, which is caused, for example, by the selected charging program, the processing unit 6 can initiate a change to the vehicle's charging program depending on the time remaining until the end of the charging process and / or a target state of charge of the energy storage device 1, which results in an increase in the charging current I. This is particularly necessary if the actual charging current results in a significantly later end to the charging process EL or if the energy storage device 1 of the vehicle 2 would not reach a state of charge (SOC) desired by the vehicle user by the next departure time.
[0067] For error case 2:
[0068] If a control intervention SE is detected by the processing unit 6 during the charging process, the processing unit 6 sends a wake-up signal AS at regular intervals, for example every five minutes, to maintain an active state of the vehicle data bus system. This wake-up signal AS can be implemented, for example, by regularly querying the vehicle data bus system. The vehicle data bus system thus remains active and does not enter sleep mode. This prevents fault condition 2.
[0069] If the vehicle data bus system is already in standby mode due to the interruption of the charging process UL caused by the control intervention SE, an activation signal AS is transmitted to the vehicle data bus system, which interrupts the standby mode of the vehicle data bus system, at least briefly. In this transmission, the wake-up signal AS is sent specifically as a short message via the short message service to the vehicle's telecommunications module 2, which is connected to the mobile network MN, since communication via the mobile data network of the mobile network MN may not be possible when the vehicle data bus system is in standby mode.
[0070] For error case 3:
[0071] If, due to the duration of the control intervention SE and the associated interruption of the charging process UL, vehicle 2 loses authentication with energy source 3, a request signal for re-authentication of vehicle 2 with energy source 3 is transmitted to vehicle 2 and / or energy source 3 in addition to the wake-up signal AS. This initiates a new authentication attempt with energy source 3. In particular, sufficient technical conditions must be present on both the vehicle 2 and energy source 3 side to establish standard communication with authentication information via the charging cable 8, for example, according to ISO 15118-20. If the authentication attempt is successful, energy source 3 can again specify a maximum available charging current I greater than 0 A after the control intervention SE has ended, and vehicle 2 continues the charging process.
[0072] In a similar way to how the error cases can occur in combination, it may be necessary to carry out several of the previously described measures to avoid the error cases one after the other in order to continue the charging process of the energy storage device 1 without errors after the end of the control intervention SE.
[0073] In another possible embodiment of the device 5, it is provided that information IN determined by the computing unit 6 during the monitoring of the charging process of the energy storage device 1 is forwarded to at least one application unit 7. Such an application unit 7 is, for example, an end device of a vehicle user, such as a mobile phone, which informs the vehicle user about the status of the charging process after receiving the information IN. The application unit 7 can also be an end device of a network operator or energy supplier, which informs them about the status of the charging process after receiving the information IN, so that they can check whether an external control intervention SE is being implemented correctly.
Claims
Patent claims 1. Method for carrying out a charging process of an electrically powered vehicle (2), characterized in that - a charging process of an electrical energy storage device (1) of the vehicle (2) carried out at an energy source (3) is monitored by means of a vehicle-external computing unit (6) that is coupled or can be coupled to the vehicle (2) in terms of data technology and - if the charging process (UL) is interrupted by the processing unit (6), a wake-up signal (AS) is transmitted by the processing unit (6) to a vehicle data bus system required for the execution of the charging process and / or - after a resumption of the charging process following an interruption or a temporary reduction of the charging current (I) carried out by means of the energy source (3), it is checked by means of the processing unit (6) whether a charging current on the vehicle side is limited to a value which is less than a maximum charging current (I) that can be provided by the energy source (3), and if a limitation exists by means of the processing unit (6), the vehicle-side limited value of the charging current (I) is increased depending on a time remaining until the end of the charging process and / or a target state of charge of the energy storage device (1).
2. Method according to claim 1, characterized in that a signal for maintaining an active state of the vehicle data bus system is transmitted as a wake-up signal (AS).
3. Method according to claim 2, characterized in that The signal is transmitted to the vehicle data bus system at regular intervals.
4. Method according to claim 1, characterized in that, when the computing unit (6) detects a sleep state of the vehicle data bus system resulting from an interruption of the charging process (UL), an activation signal is transmitted to the vehicle data bus system as a wake-up signal (AS).
5. Method according to one of the preceding claims, characterized in that, when the computing unit (6) detects a loss of authentication of the vehicle (2) at the energy source (3) resulting from an interruption of the charging process (UL), a request signal for re-authentication of the vehicle (2) at the energy source (3) is transmitted to the vehicle (2) and / or the energy source (3) by means of the computing unit (6).
6. Method according to one of the preceding claims, characterized in that the monitoring of the charging process - by means of the computing unit (6) a target charging current and an actual charging current are queried from the vehicle (2) and / or the energy source (3), - values of the target charging current and the actual charging current are transmitted to the computing unit (6) by means of the vehicle (2) and / or the energy source (3), - the values of the target charging current and the actual charging current are compared using the computing unit (6) and - the interruption of the charging process (UL) is detected by means of the processing unit (6) when the actual charging current is zero and / or - the vehicle-side limitation of the charging current (I) is detected by means of the computing unit (6) when the actual charging current is less than the maximum charging current (I) that can be provided by the energy source (3).
7. Method according to one of the preceding claims, characterized in that the data connection of the vehicle (2) with the computing unit (6) is carried out by means of a mobile network (MN).
8. Method according to claim 7, characterized in that the wake-up signal (AS) is transmitted to the vehicle (2) as a short message via a short message service over the mobile network (MN).
9. Method according to one of the preceding claims, characterized in that a cloud server or backend server is used as the central computing unit (6).
10. Device (5) for carrying out a charging process of an electrically powered vehicle (2), characterized in that - the vehicle (2) can be connected or is connected to an external computing unit (6) via data technology and - the computing unit (6) is formed, - to monitor a charging process of an electrical energy storage device (1) of the vehicle (2) carried out at an energy source (3) and - to transmit a wake-up signal (AS) to a vehicle data bus system required for the execution of the charging process in the event of an interruption of the charging process (UL) detected by the processing unit (6) and / or - after resuming the charging process following an interruption or a temporary reduction of the charging current (I) by means of the energy source (3), to check whether the vehicle-side charging current (I) is limited to a value that is lower than the maximum charging current (I) that can be provided by the energy source (3), and if such a limitation exists, to increase the vehicle-side limited value of the charging current (I) depending on the time remaining until the end of the charging process and / or a target state of charge of the energy storage device (1).