Method and device for controlling a charging current supplied from outside a motor vehicle

Abstract

Motor vehicle charging current control device, designed to control a charging current supplied from outside (1) a motor vehicle for an energy storage device (4) in the motor vehicle (2), with - a charging current information device (6) designed to be arranged in a motor vehicle (2) and to generate internal charging current information which is a proposed upper limit for a charging current, and - a charging current limiting device (8) designed to be arranged in the motor vehicle (2) and to limit the charging current to a limit value below the maximum possible charging current, depending on the internal charging current information, wherein the charging current information device (6) is configured to transmit the internal charging current information to the charging current limiting device (8), wherein the charging current limiting device (8) is configured to change the limit value depending on the internal charging current information, and wherein the internal charging current information is generated at least partially in the motor vehicle (2).

Description

[0001] The present invention relates to a method and a device for controlling a charging current supplied from outside a motor vehicle for an energy storage device in the motor vehicle, wherein the charging current is determined in such a way that the available resources can be distributed among as many motor vehicles as possible and the available resources can be distributed individually and in an optimized manner among the vehicles connected to an infrastructure.

[0002] Significant development efforts are being made worldwide to enable mobility based on electric power. A key challenge is storing the electrical energy needed to power a vehicle in the vehicle's energy storage system. Another challenge is recharging the vehicle's energy storage system.

[0003] Smart grids have been proposed that make the price of energy consumption dependent on the availability of electricity. Furthermore, it has been suggested that these smart grids issue a signal indicating that more electricity can be fed into the grid than is currently being drawn. Based on this signal, a vehicle's energy storage system could then be charged. However, this approach has the disadvantage that a vehicle's energy storage system will not charge if the grid is overloaded.

[0004] DE 10 2008 023 586 A1 discloses a method for determining a charging strategy for charging a vehicle energy storage device, whereby optimal charging processes and improved utilization of the energy used in the vehicle, resulting in fuel savings, are achieved through vehicle operating profiles. With a first charging strategy, the desired state of charge of the vehicle energy storage device can be 80%, and with a second charging strategy, the maximum desired state of charge of the vehicle energy storage device can be 70-75%.

[0005] The invention aims to create a device and a method in which the charging current is selected in such a way that, on the one hand, the infrastructure is not overloaded and, on the other hand, the energy storage of the motor vehicle is charged as completely as possible until the time of continuing the journey.

[0006] The object of the invention is achieved by a motor vehicle charging current control device designed to control a charging current supplied from outside the motor vehicle to an energy storage device within the motor vehicle. The motor vehicle charging current control device comprises a charging current information device designed to be installed in the motor vehicle and to generate internal charging current information, which is a proposed upper limit for the charging current. The motor vehicle charging current control device comprises a charging current limiting device designed to be installed in the motor vehicle and to limit the charging current, depending on the internal charging current information, to a limit that is below the maximum possible charging current. The charging current information device is designed to transmit the internal charging current information to the charging current limiting device.The charging current limiting device is designed to change the variable limit value depending on the internal charging current information. This internal charging current information is generated, at least in part, within the vehicle.

[0007] Since the vehicle does not draw the maximum possible charging current from the infrastructure, the infrastructure can charge more vehicles simultaneously. Furthermore, it prevents the infrastructure from collapsing due to excessive current draw, for example, due to a blown fuse.

[0008] The charging current information device can be coupled with a location tracking device that determines the current location of the vehicle. The charging current information device can be configured to generate internal charging current information depending on the location of the vehicle.

[0009] The charging current information device can be configured to generate internal charging current information based on current time information. This current time information can include a time and / or a date (weekday, holiday, working day).

[0010] The charging current information device can be configured to determine the expected parking duration of the vehicle based on the location and / or current time information. The generated internal charging current information can have a higher suggested upper limit for a shorter expected parking duration and a lower suggested upper limit for a longer expected parking duration. This configuration also allows the vehicle charging current control device according to the invention to ensure that, on the one hand, the infrastructure is not overloaded and, on the other hand, that the infrastructure can provide charging current to as many vehicles as possible. Furthermore, it enables the vehicle's energy storage system to be charged as completely as possible according to the driver's wishes.

[0011] In a particularly advantageous embodiment, the vehicle charging current control unit can be configured to determine the current state of charge of the energy storage device and to calculate the desired state of charge after charging. The difference between the desired state of charge after charging and the current state of charge indicates the charge to be supplied to the vehicle's energy storage device during the vehicle's parking period. The upper limit can be the quotient of this charge and the expected parking duration at the charging station.

[0012] The charging current information device can determine whether the current location is where the vehicle is typically parked overnight for an extended expected period. This location could, for example, be the owner's residence.

[0013] The charging current information device can determine whether the current location is where the vehicle is typically parked during the day for an extended expected parking period. This location could, for example, be the owner's workplace.

[0014] The charging current information device can determine whether the current location is one where a motor vehicle is typically parked for a shorter expected parking duration. This location could, for example, be a parking garage at a shopping center.

[0015] Furthermore, the charging current information device can determine whether the current location is a place where a motor vehicle is usually parked for a longer expected parking period, such as in an airport parking garage.

[0016] The charging current information device can be configured so that the internal charging current information has a higher suggested upper limit for a shorter expected parking duration at a charging station and a lower suggested upper limit for a longer expected parking duration at the charging station.

[0017] The charging current information device can determine whether the current location is in a first or second geographic area. The internal charging current information can display a first suggested limit if the location is in the first geographic area, and a second suggested limit if the location is in the second geographic area. A geographic area can be a state. Different states may have different limits on the charging current a vehicle can draw from a charging station. This allows the vehicle to adapt to local regulations without requiring complex reconfiguration.

[0018] The charging current information device can be configured to determine the variable limit value based on information from the vehicle driver. For example, the driver can specify the desired state of charge that must be reached by a driver-specified time. The driver can, for instance, specify a departure time and indicate that the energy storage system must reach a predetermined state of charge by that time, such as being fully charged.

[0019] The vehicle charging current control unit can receive external charging current information. The variable limit can be determined based on both the internal and external charging current information. For example, the external charging current information can indicate that the charging current must be limited to a threshold predetermined by the infrastructure, because otherwise the infrastructure will be overloaded.

[0020] However, it is also conceivable that the infrastructure can provide more energy than is demanded by vehicles, for example, because a solar panel is generating a lot of electricity due to the current solar irradiance. In this case, it is possible that the energy storage system will be charged faster and with a higher current than the internal charging current information indicates. Furthermore, the vehicle's energy storage system can be charged beyond the level specified by the driver or any device in the vehicle. If the external limit is higher than the internal limit, the charging current can be higher than specified by the internal limit.

[0021] The charging station can be configured to allow charging resources to be reserved at specific locations and times via a service. For example, a driver can use an internet connection to reserve charging times and charging points at stations located along their planned route.

[0022] Furthermore, the charging station can use a service to display the charging current it can provide. This allows a vehicle's system to search for a suitable charging station that can provide an appropriate, for example, the highest possible, charging current.

[0023] Depending on temporary conditions, such as the availability of solar power, the charging station can adjust the information about the available charging current. Vehicles can therefore automatically make optimal use of these dynamic charging resources.

[0024] The invention also discloses a method for controlling the charging of a motor vehicle's energy storage device with a charging current supplied from outside the vehicle. The method comprises generating internal charging current information, which is a proposed upper limit for the charging current, and limiting the charging current based on this internal charging current information to a limit below the maximum possible charging current. The steps of generating the internal charging current information and limiting the charging current are performed within the vehicle. The step of generating the internal charging current information takes into account current location information and / or current time information and / or external charging current information and / or information from the driver.

[0025] The process can be further developed as previously described with regard to the motor vehicle charging current control device.

[0026] The invention is described in more detail below with reference to the figure. This detailed description is intended for the information of those skilled in the art and is not to be construed as limiting. Fig. Figure 1 shows a schematic representation of a motor vehicle with an electric charge storage device and an external infrastructure for charging the charge storage device.

[0027] Fig.Figure 1 shows a motor vehicle 2 with a charge storage device 4, which is connected to an infrastructure 1 for charging. The charge storage device 4 is designed to supply electricity to a drive motor of the motor vehicle 2. The charge storage device 4 is charged from an external charging station 26 by means of a charging cable 10, which is connected to a socket 12 of the motor vehicle 2. The charge storage device 4 can be a lithium-ion battery.

[0028] The infrastructure comprises the first charging station 26 and the second charging station 28, which are connected to a distribution unit 30. Solar cells 38 are also connected to the distribution unit 30. The distribution unit 30 receives electrical energy via a line 32. The distribution unit 30 is also connected to a network unit 34, which can transmit data over a network.

[0029] The motor vehicle 2 comprises a charging current information device 6, which is connected to a location tracking device 20, a time tracking device 22, and an input device 24, into which a driver of the motor vehicle 4 can enter information, for example, about the planned time of departure. The charging current information device 6 is also connected to a charging current limiting device 8. The charging current limiting device 8 limits the charging current that flows from the charging station 26 via line 10 into the charge storage device 4. Furthermore, the motor vehicle 2 comprises a receiving device 14, which receives external charging current information and forwards it to the charging current limiting device 8 via line 18.

[0030] When a driver parks the vehicle 2, the charging cable 10 is connected to the socket 12. The charging station 26 supplies an electrical current to charge the charge storage unit 4 or the battery 4. A number of vehicles can be connected to the infrastructure 1 at charging stations 26, 28, and other charging stations not shown. If a number of vehicles are connected to the infrastructure 1, there is a risk of overloading the infrastructure. In the event of an overload, for example, a fuse may trip, which could result in none of the vehicles connected to the infrastructure 1 receiving power to charge their respective charge storage units 4.

[0031] The vehicle charging current control device according to the invention comprises a charging current information device 6, which is arranged in a vehicle and generates internal charging current information, which is a proposed upper limit for a charging current. The charging current information is transmitted to the charging current limiting device 8. The charging current limiting device 8 is arranged in the vehicle 2 and limits the charging current, depending on the internal charging current information, to a limit that is below the maximum possible charging current. The charging current limiting device 8 is configured to change the limit depending on the internal charging current information.

[0032] The location tracking device 20 can determine the current location of the vehicle 2. The location tracking device 20 can, for example, include a GPS sensor that determines the position of the vehicle 2 based on satellite signals. The location information is transmitted from the location tracking device 20 to the charging current information device 6. The charging current information device 6 can generate the internal charging current information based on the location information transmitted by the location tracking device 20.

[0033] The vehicle 2 is equipped with a time determination device 22, which generates current time information. This time information can include a time, a date, and other information, such as whether it is a weekday, a public holiday, or a weekend. The current time information is transmitted to the charging current information device 6. The charging current information device 6 can then generate the internal charging current information based on the current time information.

[0034] The charging current information unit 6 determines the expected parking duration of the vehicle based on the location and / or the current time information. The internal charging current information includes a higher suggested upper limit for the charging current for a shorter expected parking duration and a lower suggested upper limit for the charging current for a longer expected parking duration. For example, the upper limit for the charging current could be the ratio of the charge required to fully charge the charge storage unit 4 to the expected parking duration.

[0035] The charging current information unit 6 can determine whether the current location is where the vehicle 2 is typically parked overnight for an extended period. This location could be the owner's residence. The charging current information unit 6 can also determine whether the current location is where the vehicle is typically parked during the day for an extended period. This location could be the owner's workplace. Furthermore, the charging current information unit 6 can determine whether the current location is where a vehicle is typically parked for a shorter period, such as in a shopping center.Furthermore, the charging current information device 6 can determine whether the current location is one where a vehicle is typically parked for a longer expected parking duration, such as at an airport. The charging current information device 6 is configured such that the internal charging current information provides a higher suggested upper limit for the charging current when the expected parking duration is shorter and a lower suggested upper limit for the charging current when the expected parking duration is longer.

[0036] The driver can enter the time at which they expect to resume driving and at which the charging storage unit 4 should be as fully charged as possible into the input device 24. The information about the expected resumption of driving can be transmitted from the input device 24 to the charging current information unit 6. The charging current information unit 6 can determine the variable limit value for the charging current based on the information from the driver of the vehicle 2 about the expected time of resuming driving.

[0037] The distribution unit 30 and / or the charging station 26 can transmit external charging current information to the vehicle 2, for example via line 10. This external charging current information may indicate that the infrastructure is overloaded and the charging current must be lower than a limit value specified in the external charging current information. However, it is also possible that the infrastructure 1 can provide more current, and consequently, the external charging current information may indicate that a higher current can be requested from the charging station 26. This could be the case, for example, if the solar cells 38 generate more current due to strong sunlight than is currently being supplied to the vehicles 2 by the charging stations 26 and 28.The charging current limiting device can receive the external charging current information via line 18 from receiver 14, which receives the external charging current information and determines the variable limit value depending on the internal charging current information and the external charging current information. The charging stations 26 and 28 do not need to be active components. The charging stations can be passive components that merely comprise a connection. For example, a charging station at a residential building or in a garage can simply comprise a power connection, such as a wall socket.

[0038] The charging current information device 6, the charging current limiting device, the location determination device 20 and / or the time determination device 22 can be implemented by separate components or assemblies, or by a single component or assembly. The charging current information device 6, the charging current limiting device, the location determination device 20 and / or the time determination device 22 can be implemented, at least partially, by software.

[0039] Since the vehicle does not draw the maximum possible charging current from the infrastructure, the infrastructure can charge more vehicles simultaneously. Furthermore, it prevents the infrastructure from collapsing due to excessive current draw, for example, due to a blown fuse. In addition, the inventive device and method allow the energy storage of at least one vehicle to be charged individually and in an optimized manner, taking into account both the driver's wishes and the current capacity of the infrastructure.

Claims

[1] Motor vehicle charging current control device designed to control a charging current supplied from outside (1) a motor vehicle for an energy storage device (4) in the motor vehicle (2), with - a charging current information device (6) designed to be arranged in a motor vehicle (2) and to generate internal charging current information which is a proposed upper limit for a charging current, and - a charging current limiting device (8) designed to be arranged in the motor vehicle (2) and to limit the charging current to a limit value below the maximum possible charging current, depending on the internal charging current information, wherein the charging current information device (6) is configured to transmit the internal charging current information to the charging current limiting device (8), wherein the charging current limiting device (8) is configured to change the limit value depending on the internal charging current information, and where the internal charging current information is generated at least partially in the motor vehicle (2). [2] Motor vehicle charging current control device according to claim 1, characterized by , that charging current information device (6) is coupled with a location determination device (20) which determines the current location of the motor vehicle, and the charging current information device (6) is designed to generate the internal charging current information depending on the location of the motor vehicle (2). [3] Motor vehicle charging current control device according to claim 1 or 2, characterized by, that the charging current information device (6) is designed to generate the internal charging current information as a function of current time information. [4] Motor vehicle charging current control device according to one of claims 1 to 3, characterized by , that the charging current information device (6) is designed to determine an expected parking duration of the motor vehicle (2) depending on the location and / or the current time information, and that the internal charging current information has a higher proposed upper limit for the charging current for a shorter expected parking duration and a lower proposed upper limit for the charging current for a longer expected parking duration. [5] Motor vehicle charging current control device according to one of claims 2 to 4, characterized by , that the charging current information device (6) is designed to determine whether the current location - the place where the motor vehicle (2) is usually parked during the night for a longer expected parking period, - the place where the motor vehicle (2) is usually parked during the day for a longer expected parking period, and / or - a place where a motor vehicle (2) is usually parked for a shorter expected parking period, - a place where a motor vehicle (2) is usually parked for a longer expected parking period, wherein the charging current information device (6) is configured such that the internal charging current information has a higher proposed upper limit for the charging current for a shorter expected parking period and a lower proposed upper limit for the charging current for a longer expected parking period. [6] Motor vehicle charging current control device according to one of claims 2 to 5, characterized by, that the charging current information device (6) is configured to determine whether the current location is in a first or a second geographical area, and the internal charging current information has a first proposed limit if the location is in the first geographical area and the internal charging current information has a second proposed limit if the location is in the second geographical area. [7] Motor vehicle charging current control device according to any of the preceding claims, characterized by , that the charging current information device (6) is designed to determine the variable limit value for the charging current depending on information from the driver of the motor vehicle (2). [8] Motor vehicle charging current control device according to any of the preceding claims, characterized by, that the motor vehicle charging current control device is configured to receive external charging current information, and the charging current limiting device (8) is configured to determine the variable limit value depending on the internal charging current information and the external charging current information. [9] Method for controlling the charging of an energy storage device (4) of a motor vehicle (2) with a charging current supplied from outside (1) the motor vehicle, comprising the following steps: - Generating internal charging current information, which is a suggested upper limit for a charging current, and - Limiting the charging current to a limit below the maximum possible charging current, depending on the internal charging current information, whereby the steps of generating the internal charging current information and limiting the charging current are carried out within the vehicle. [10] Method according to claim 9, characterized by , that the step of generating the internal charging current information takes into account current location information and / or current time information and / or external charging current information and / or information from the driver.

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