On-board power system for a vehicle, vehicle and use of an on-board power system

Abstract

The invention relates to an on-board power system (100) for a vehicle (F) having one, in particular only one, main energy store (B) for supplying electrical energy to main consumers, for example electric motors or electric machines, of the vehicle (F), comprising one, in particular only one, DC / DC converter for providing electrical energy from the main energy store (B) to low-voltage consumers (L) and one, in particular only one, auxiliary energy store (LV) for supplying electrical energy to the low-voltage consumers (L), in particular to safety-relevant driving assistance functions, wherein the on-board power system (100) is wired in such a way that at least two redundant sub-networks (Grid1, Grid2) are formed in order to provide fail-safe protection when supplying the low-voltage consumers (L). The invention also relates to a vehicle having such an on-board power system and to the use of such an on-board power system.

Description

Technical Field

[0001] The present invention relates to an onboard electrical system for a vehicle, a vehicle having such an onboard electrical system, and the use of such an onboard electrical system. Background Technology

[0002] Modern hybrid and electric vehicles have an onboard electrical network that supplies energy to both the electric drive units and a large number of low-voltage electrical appliances. Particularly in vehicles with automated or even autonomous driving capabilities, the requirements for the availability and fail-safe protection of the power supply to safety-related driver assistance systems are constantly increasing. These requirements include, for example, longitudinal and lateral guidance functions, collision avoidance functions, and driver support functions in emergency driving situations. Typically, low-voltage electrical appliances operate at voltage levels of 12V, 24V, or 48V, while the vehicle's main energy storage is constructed as a high-voltage battery with a significantly higher voltage level. To couple these voltage levels, DC / DC converters and low-voltage batteries are used, typically integrated separately into the vehicle. For safety applications in the autonomous driving field, this places special requirements on the architecture of the low-voltage power supply.

[0003] In existing technologies, low-voltage power is typically supplied using individual devices, each meeting current quality management standards. However, this conventional solution has limited fault tolerance because it cannot easily ensure power supply to safety-critical functions in a redundant manner in the event of failure of a single device or part of the network component. This is particularly true for Safety Driving Capability Levels 3 to 5 and higher (where the vehicle is independently guided for extended periods), where a simple 12V network without specific fail-safe protection is insufficient. Furthermore, it is known to construct low-voltage networks using multiple batteries and multiple DC / DC converters to establish redundancy. However, this approach involves increased component consumption, additional packaging, and associated costs, and can be costly for vehicle manufacturers during integration. Therefore, there is a need for an onboard electrical network architecture that provides high fail-safe protection and redundant low-voltage power supply for safety-critical functions while reducing component consumption. Summary of the Invention

[0004] Therefore, the objective of this invention is to overcome at least part of the aforementioned disadvantages. In particular, the objective of this invention is to provide a safe low-voltage network that enables redundant power supply for safety-related driver assistance functions using only a single primary energy storage unit, a single DC / DC converter, and a single auxiliary energy storage unit. Furthermore, the objective of this invention is to provide an onboard electrical grid architecture that saves on batteries or DC / DC converters and housings, and that can be compactly, cost-effectively, and manufacturer-friendly for integration into vehicles with autonomous driving capabilities. Moreover, this low-voltage power supply architecture should enable fault-tolerant operation and provide appropriate measures for fault identification and disconnection of faulty components and subnetworks.

[0005] The above-mentioned task is accomplished by using an on-board electrical system for a vehicle having the features of independent claim 1, a vehicle having the features of parallel claim 12, and an on-board electrical system having the features of independent claims 14 and 15.

[0006] Further features and details of the invention are given in the dependent claims, the description, and the drawings. Of course, the features and details described in conjunction with the in-vehicle electrical network according to the invention also apply to vehicles and uses according to the invention, and vice versa; therefore, the disclosures regarding individual aspects of the invention are always cross-referenced or may be cross-referenced.

[0007] The term "vehicle electrical network" can be understood as including all wires, switches, energy storage devices, converters, and electronic components in a vehicle used for distributing electrical energy, with particular consideration given to the power supply for low-voltage electrical appliances and safety-related driver assistance functions.

[0008] The term "main energy storage unit" can be understood as a high-voltage battery constructed to supply electrical energy to the vehicle's main electrical appliances, such as electric motors or generators.

[0009] The term "auxiliary energy storage device" can be understood as a low-voltage energy storage device, particularly a 12V, 24V, or 48V battery, which is configured to supply electrical energy to low-voltage loads.

[0010] The term "low-voltage load" can be understood as one or more electrical appliances operating at a voltage level of approximately 12V, 24V, or 48V, particularly safety-related driver assistance functions.

[0011] The term "sub-network" or "grid" can be understood as each electrical segment of the onboard electrical network, which has its own power supply and switching path and can be disconnected individually in the event of a fault.

[0012] The term "power electronics" can be understood as electronic circuits and components installed in the vehicle's electrical system for controlling and switching large currents and high voltages.

[0013] According to a first aspect, the present invention relates to an onboard electrical network for a vehicle, particularly a hybrid or electric vehicle, preferably an automated to autonomous driving vehicle.

[0014] The vehicle may have one, in particular only one, main energy storage device, such as a high-voltage battery (also known as an HV battery), such as a 400V battery, an 800V battery, or a 1000V battery, to supply electrical energy to the vehicle’s main electrical appliances (such as an electric motor or motor).

[0015] The on-board electrical grid has the following components:

[0016] —A single, in particular, DC / DC converter is used to supply electrical energy from the main energy storage to a low-voltage load, which has a voltage level of, for example, 12V, 24V, or 48V.

[0017] —One, and especially only one, auxiliary energy storage device, such as a low-voltage battery (also known as an LV battery), such as a 12V, 24V, or 48V battery, is used to supply power to low-voltage loads, and it can be particularly configured for safety-related driving assistance functions.

[0018] The vehicle-mounted electrical network is wired to form at least two redundant sub-networks, thereby providing fail-safe protection when supplying power to low-voltage loads.

[0019] The main energy storage device can be configured as a high-voltage battery, for example, to supply electrical energy to the vehicle's main electrical appliances (especially electric drive units).

[0020] Low-voltage loads can be supplied with electrical energy at a lower voltage level through DC / DC converters and / or auxiliary energy storage devices.

[0021] The DC / DC converter is electrically coupled to the main energy storage unit and converts the high voltage of the high-voltage battery to a controlled low voltage level, thereby enabling reliable operation of low-voltage loads.

[0022] The auxiliary energy storage device provides an independent low-voltage storage source, which can supply power for safety-related driving assistance functions and provide independent power supply in the event of failure of the DC / DC converter and / or sub-network.

[0023] By wiring the vehicle electrical network into at least two redundant sub-networks, low-voltage loads can be powered through multiple electrically isolated paths. Each sub-network can have its own switching elements and wiring paths through which power from DC / DC converters and / or auxiliary energy storage devices is directed to the low-voltage load. This redundancy design ensures that in the event of a failure in one sub-network, the other sub-network can still power the low-voltage load (especially safety-related functions).

[0024] Furthermore, it is conceivable that a DC / DC converter is not only constructed as a single converter, but also has multiple electrically isolated outputs, which can be assigned to a sub-network respectively.

[0025] Furthermore, it is conceivable that the auxiliary energy storage device can be constructed as a battery module with multiple cells connected in parallel or series, wherein each individual module can be assigned to a sub-network to further improve redundancy.

[0026] The 12V, 24V, and 48V voltage levels mentioned are exemplary; the concept can be applied to other low voltage levels within the normal range, as long as low-voltage loads are being powered in the vehicle.

[0027] This architecture enables a fail-safe low-voltage power supply that supports safe driving capabilities with higher levels of automation, without requiring multiple HV energy storage units or multiple DC / DC converters, thereby reducing component, packaging costs, and overall expenses.

[0028] The measures described in the dependent claims can advantageously improve and enhance the aspects of the invention described in the independent claims.

[0029] Furthermore, it can be specified that the vehicle electrical network is wired to allow low-voltage loads and other electrical appliances in the vehicle to be powered via auxiliary energy storage and a DC / DC converter. Alternatively, it can be specified that the vehicle electrical network is wired to allow only low-voltage loads to be powered via auxiliary energy storage and a DC / DC converter, or only auxiliary energy storage and / or only a DC / DC converter.

[0030] In this way, different operating modes can be achieved with the help of a switch matrix. In these operating modes, low-voltage loads and other electrical appliances, if necessary, can be flexibly fed through different power supply paths.

[0031] During normal operation, it can be specified that the DC / DC converter can cover the base load of low-voltage appliances from a high-voltage battery. Furthermore, it can be specified that the DC / DC converter can charge an auxiliary energy storage device during normal operation. Additionally, it is conceivable that the auxiliary energy storage device can handle short-term power peaks during normal operation. It can also be specified that the DC / DC converter and the auxiliary energy storage device can share the load during normal operation. Other appliances, such as comfort functions and / or entertainment functions, can also be powered through a combination of auxiliary energy storage and the DC / DC converter during normal operation.

[0032] In the event of a DC / DC converter failure, the vehicle's electrical grid can switch to a mode that supplies only low-voltage loads. Other electrical appliances in the vehicle can then be shut down or continue to be powered through the remaining power supply paths, with safety-related functions given priority for isolation and power supply.

[0033] Furthermore, it can be stipulated that in the event of a failure in the affected subnetwork, the affected subnetwork can automatically disconnect.

[0034] This allows for targeted isolation of faulty subnetworks. Fault conditions can be characterized, for example, by short circuits, open circuits, unacceptable voltage or current states, or incorrect current directions within the subnetwork. Each subnetwork can be equipped with its own switching elements, which open in the event of a fault, thus electrically isolating the affected subnetwork from the rest of the vehicle's electrical network. The monitoring or diagnostic unit can continuously detect the relevant measurement signals and send a shutdown signal to the switch when predetermined limits are exceeded. By disconnecting the faulty subnetwork, the fault condition is prevented from spreading from one subnetwork to another or to the main energy storage unit and / or DC / DC converter. Intact subnetworks can continue to draw energy from the DC / DC converter and / or auxiliary energy storage unit, thus allowing low-voltage loads with safety-related functions to continue operating.

[0035] Furthermore, it can be specified that in the event of a failure of an affected electronic component (e.g., a DC / DC converter), the affected electronic component (e.g., a DC / DC converter) can automatically disconnect, particularly from both sub-networks. Additionally, it can be specified that the on-board electrical network is wired such that, in the event of a failure of the auxiliary energy storage device, the auxiliary energy storage device can automatically disconnect, particularly from both sub-networks.

[0036] This concretizes fault tolerance at the component level. The DC / DC converter is connected to the sub-network via appropriate switches. In fault conditions, such as internal defects, control errors, and / or abnormal temperature rises in the DC / DC converter, it can be specified that the assigned switches be opened, electrically isolating the DC / DC converter from both the first and second sub-networks.

[0037] The same applies to auxiliary energy storage devices: in the event of internal defects, voltage status errors, and / or short circuits, the auxiliary energy storage device can be completely isolated from the two sub-networks via its connection switch. This disconnection prevents unwanted fault currents, feedback, and / or voltage drift in the low-voltage supply.

[0038] It is also conceivable that component disconnection can be performed not only completely, but also in stages, for example, by first limiting the current and then achieving complete disconnection while the fault condition persists.

[0039] It can also be considered that the component disconnection is not permanent, but can continue for a specific period of time. If the fault no longer exists after the specific period of time, the component can be put back into operation.

[0040] Combined with redundant subnetworks, this proposed architecture enables low-voltage loads to continue to be powered in safe mode by the remaining functional components in the event of failure of electronic components and / or auxiliary energy storage.

[0041] In addition, it can be specified that the on-board electrical network has two switches for the DC / DC converter.

[0042] These switches can be individually positioned between the output of the DC / DC converter and the corresponding sub-network. This allows for targeted control of the connection between the DC / DC converter and the sub-network. In one operating state, both switches can be closed, allowing the DC / DC converter to power both sub-networks in parallel. In another operating state, it can be specified that only one switch is closed, so the DC / DC converter powers only one sub-network, while the other sub-network is disconnected and can be powered via an auxiliary energy storage device if necessary. In the event of a sub-network failure, the corresponding switch can open while the other remains closed, allowing the DC / DC converter to continue powering the fault-free sub-network.

[0043] In one implementation, the switch can be configured as an electronic power switch, which can be integrated into a common power electronics device. Advantageously, in addition to its switching function, the switch can also perform additional monitoring, protection, and / or diagnostic functions. Alternatively, when electrical isolation with a large air gap or creepage distance is required, a mechanical or electromechanical switch can be used.

[0044] In addition, it can be specified that the on-board electrical grid has two switches for auxiliary energy storage.

[0045] These switches can be individually installed between the auxiliary energy storage unit and one of the sub-networks. This allows for flexible connection between the auxiliary battery and each individual sub-network.

[0046] In one implementation, the switch can be configured as an electronic power switch, which can be integrated into a common power electronics device. Advantageously, in addition to its switching function, the switch can also perform additional monitoring, protection, and / or diagnostic functions. Alternatively, when electrical isolation with a large air gap or creepage distance is required, a mechanical or electromechanical switch can be used.

[0047] During normal operation, it can be specified that the auxiliary energy storage unit can power both sub-networks and / or selectively power a chosen sub-network. In the event of a failure in one sub-network, a relevant switch can be opened, allowing the battery to power only the other, still functioning sub-network.

[0048] By combining the switches of the DC / DC converter and the switches of the auxiliary energy storage device, a switch matrix can be formed, which can be used to realize different power supply combinations.

[0049] Furthermore, it can be specified that the vehicle-mounted electrical network has (smart) switches configured to identify at least one fault condition and function like a fuse, such as at least one of the following fault conditions: component failure, network failure, overcurrent, voltage state (e.g., including overvoltage and / or undervoltage) and / or incorrect current direction.

[0050] These switches can be equipped with measurement and / or evaluation functions, enabling them to detect electrical parameters such as current, voltage, and current direction, and identify fault conditions based on defined thresholds. Component faults can be identified, for example, through internal diagnostics of the power semiconductor. Network faults can be identified, for example, through unexpected line interruptions or short circuits. In the event of an overcurrent (e.g., caused by a short circuit in a low-voltage load or a defective appliance), the switch can interrupt the current path like a fuse. Unacceptable voltage conditions (e.g., overvoltage or undervoltage on a low-voltage load) can be identified and used to disconnect the corresponding path to protect connected appliances. Incorrect current direction may indicate that energy is flowing back to the main energy storage unit or between sub-networks in an unacceptable manner.

[0051] Unlike purely passive fuses, these switches can be controlled to reclose after fault analysis and / or selectively manipulated by the control unit to enable limited restart and / or emergency operation. This supports fault-tolerant operation and allows the onboard electrical system to dynamically adapt to different fault conditions.

[0052] Furthermore, it can be specified that the vehicle-mounted electrical network has, for example, an integrated switch in a power electronic device.

[0053] Integrated switches can be implemented as semiconductor power switches within a common power electronics device that controls the current path within the module. They can be combined with drive circuitry, current and voltage measurements, and protection functions, enabling the switch matrix to operate compactly, quickly, and efficiently. Such power electronics can be part of a DC / DC converter and / or auxiliary battery interface electronics, providing multiple switching paths for different sub-networks and load groups.

[0054] Furthermore, it can be specified that the DC / DC converter and the auxiliary energy storage device each have a power electronic device or a common power electronic device, which may, for example, have an integrated switch.

[0055] The power electronics of the DC / DC converter perform the actual voltage conversion and regulation, while providing an integrated switch to distribute the DC / DC converter's output to the sub-network. The power electronics of the auxiliary energy storage unit control charging and discharging currents, provide protection functions, and regulate its connection to the sub-network via an integrated switch. Two power electronics units can be interconnected using signal technology, allowing them to exchange information about load status and fault conditions and respond to faults in a coordinated manner. A common power electronics unit can combine these functions.

[0056] Furthermore, it can be stipulated that the vehicle-mounted electrical network has a separate switch, which, for example, has its own electronic device.

[0057] Individual switches with their own electronics can be installed as independent submodules in the vehicle electrical network, for example, at critical nodes in the line route between DC / DC converters, auxiliary energy storage devices, and low-voltage loads. Each such component can provide local measurement and evaluation capabilities and independently determine the opening or closing path of the switch in the event of a fault. This supports a modular and scalable architecture, in which additional switches and subnetworks can be added relatively easily.

[0058] The combination of integrated switches in power electronics and discrete individual switches with their own electronics can realize a finely hierarchical switch matrix for vehicle power grids that is adapted to corresponding safety requirements.

[0059] Furthermore, it may be stipulated that the vehicle electrical network is provided with one, in particular only one, housing to house and / or seal all components of the vehicle electrical network, and / or to provide the vehicle electrical network in the form of a single, operable integrated module.

[0060] The housing can be constructed as a modular housing, in which the DC / DC converter, auxiliary energy storage unit, all switches, and additional electronic components (such as control and / or diagnostic units) can be mechanically and electrically integrated. The housing can be designed to occupy a defined mounting location within the vehicle and connect to the main energy storage unit, low-voltage loads, and vehicle data bus via plug-in connectors. Sealing can be achieved through seals and an appropriate housing shape to protect components from moisture, dust, and other environmental factors.

[0061] The vehicle electrical network is made easy to integrate into the vehicle by being a stand-alone module, as this module can be pre-manufactured and delivered as a complete low-voltage power supply unit and can be installed in the vehicle with a small number of connectors.

[0062] According to a second aspect, the present invention also relates to a vehicle, particularly a hybrid or electric vehicle, preferably an automated to autonomous driving vehicle, having a corresponding onboard electrical network for powering safety-related driving assistance functions on low-voltage loads.

[0063] The vehicle is therefore designed to integrate the onboard electrical grid architecture described in the first aspect within the vehicle and to supply power to low-voltage loads (on which safety-related driving assistance functions are housed). Driving assistance functions may include, for example, control devices, sensors, and actuators for longitudinal and lateral guidance of the vehicle, used within the framework of automated or autonomous driving functions. The onboard electrical grid, with a primary energy storage unit, a DC / DC converter, and an auxiliary energy storage unit, ensures that these functions are fail-safe fed through redundant subnetworks, thereby maintaining power to safety-related functions through each other subnetwork or remaining components in the event of a subnetwork or component failure. This supports higher levels of safe driving capabilities, in which the vehicle is independently guided for extended periods and the driver serves only as a backup.

[0064] Safety-related driver assistance functions may have at least one longitudinal guidance function and / or at least one lateral guidance function, such as emergency braking assist, lane keeping assist, spacing assist, speed keeping assist, reversing assist, adaptive brake lights, accident data storage and / or fatigue recognition.

[0065] Longitudinal guidance features may include, in particular, functions that automatically adjust vehicle speed and / or distance, such as emergency braking assist, which activates automatic braking in the event of an impending collision, and / or spacing assist and / or speed-keeping assist, which adjust speed and / or distance relative to the vehicle in front. Lateral guidance features may include lane-keeping assist, which keeps the vehicle within its lane through targeted steering intervention and / or warnings. Reversing assist can support the driver during maneuvering and reversing, for example, through automatic (braking and / or steering) intervention and / or suggestions. Adaptive brake lights can inform other road users about critical braking actions by adapting brake light signals to braking dynamics. Accident data storage can detect safety-related data about vehicle status and vehicle reactions before and during accidents, while fatigue detection identifies signs of decreased driver attention based on driving behavior or sensor signals and issues appropriate warnings and / or intervenes in vehicle operation, such as stopping on the shoulder.

[0066] All these functions rely heavily on a stable and fail-safe low-voltage power supply, as they are typically implemented through control devices, sensors, and actuators operating on a low-voltage onboard electrical network. The onboard electrical network architecture according to the invention, with its redundant subnetworks and fault-tolerant switch matrix, ensures that these functions continue to operate or are shut down in an orderly manner even in the event of a subnetwork or component failure, thereby enabling safe vehicle operation or a safe transition to a safe state.

[0067] According to a third aspect, the invention also relates to the use of a corresponding vehicle-mounted electrical network for providing at least one safety function, namely: for enabling the vehicle to continue operating safely, for enabling the vehicle to operate safely during a transition period until the driver is able to take over vehicle guidance, for enabling the vehicle to stop safely, for example, on the shoulder, and / or for issuing an emergency call.

[0068] This application is particularly advantageous in fault conditions, such as when a sub-network, DC / DC converter, or auxiliary energy storage device fails.

[0069] This application describes the functional application of a redundant low-voltage power supply architecture in a safety-related vehicle condition context.

[0070] "Safely continue to operate" can be understood as meaning that, despite the failure of a subnetwork and / or component, the vehicle can still continue to operate through the remaining functional power supply path, for example, at a reduced speed and / or in a limited safety mode.

[0071] "Safe operation during the transition period" specifically refers to scenarios with higher levels of automation, where the vehicle automatically identifies a malfunction and independently takes over vehicle guidance before the driver is able to regain control. During this period, safety features ensure that longitudinal and / or lateral guidance and collision avoidance continue to be guaranteed.

[0072] "Bringing a vehicle to a safe stop" specifically includes the ability to brake the vehicle in a controlled manner and guide it to a safe location (such as a curb, recess, or parking lot) when there is a serious malfunction that no longer allows for continued operation. For this purpose, a reliable power supply to driver assistance systems is also required to perform braking and steering interventions, as well as signal indications.

[0073] Emergency calls can be made via a communication interface, which is also powered by the low-voltage vehicle electrical network and automatically sends messages, including location and status data, to service providers, control centers, and / or rescue services in the event of a fault. The vehicle electrical network architecture according to the invention enables these safety functions to be specifically guaranteed through a redundant power supply structure, thereby supporting a controlled transition to a safe vehicle state even in a fault condition, preferably until the vehicle comes to a stop.

[0074] According to the fourth aspect, the present invention also relates to a corresponding use of an on-board electrical network, namely: buffering power peaks with the aid of an auxiliary battery, supplying medium loads with the aid of a DC / DC converter, and / or supplying multiple loads with the aid of a DC / DC converter and an auxiliary energy storage device.

[0075] This application is particularly advantageous during normal operation.

[0076] In this application, the combined role of the auxiliary energy storage device and the DC / DC converter in load distribution is described.

[0077] Power peaks may occur, for example, during sudden braking or steering intervention, simultaneous activation of multiple actuators, and / or the sudden activation of safety-related functions. The auxiliary battery can act as a buffer, handling such short-duration peak currents without overloading the DC / DC converter or high-voltage network. To this end, the auxiliary battery can be connected to the relevant sub-network via a switching matrix and can rapidly provide large currents, while the DC / DC converter can maintain its output power within predetermined regulation parameters.

[0078] Medium-load applications, such as continuous electrical appliances in driver assistance or other low-voltage electrical applications, can in principle be powered by a DC / DC converter. The electronic components of the DC / DC converter regulate the output voltage and current to the required values, thereby ensuring stable operation under medium loads.

[0079] Multiple loads can be powered by a DC / DC converter and an auxiliary energy storage device. Here, the DC / DC converter and auxiliary energy storage device can distribute the load among them.

[0080] Advantageously, it can be stipulated that load distribution and / or load (and / or appliance) priority sequencing can be performed by a control unit, which can be provided as another component of the vehicle electrical network or as an external component.

[0081] The control unit can accordingly operate the switches and / or determine which load groups are powered by the auxiliary battery and which are powered by the DC / DC converter.

[0082] Thus, the same advantages as those already described in terms of vehicle and application are obtained, particularly low-voltage power supply that provides fail-safe protection for safety-related functions, while achieving a compact and cost-effective implementation. Attached Figure Description

[0083] The invention will now be described in more detail with reference to the accompanying drawings. Wherein:

[0084] Figure 1 A proposed vehicle-mounted electrical grid is shown. Detailed Implementation

[0085] According to a first aspect, the present invention provides an on-board electrical network 100 for a vehicle F, particularly a hybrid vehicle or an electric vehicle, preferably an automated to autonomous driving vehicle.

[0086] The vehicle F may have one, in particular only one, main energy storage device B, such as a high-voltage battery (also known as an HV battery), such as a 400V battery, an 800V battery or a 1000V battery, to supply electrical energy to the main electrical appliances of the vehicle F (such as an electric motor or motor).

[0087] like Figure 1 As shown, the vehicle-mounted electrical network 100 has the following components:

[0088] —One, and in particular only one, DC / DC converter for supplying electrical energy from the main energy storage unit B to a low-voltage load L with a voltage level of 12V, 24V, or 48V, and

[0089] —One, especially only one, auxiliary energy storage device LV, such as a low-voltage battery (also known as an LV battery), such as a 12V battery, a 24V battery or a 48V battery, is used to supply power to a low-voltage load L (especially for safety-related driving assistance functions).

[0090] also, Figure 1This indicates that the vehicle-mounted electrical grid 100 is wired to form at least two redundant sub-networks, Grid1 and Grid2, thereby providing fail-safe protection when supplying power to the low-voltage load L.

[0091] High-voltage battery B can supply electrical energy to main electrical appliances (such as electric drive devices).

[0092] Low-voltage loads L can be supplied with electrical energy at low voltage levels through DC / DC converters and / or auxiliary energy storage devices LV.

[0093] The DC / DC converter couples the high-voltage battery B to the low-voltage network and provides a controlled low voltage to the low-voltage load L.

[0094] The auxiliary energy storage unit LV provides an independent low-voltage source, particularly for safety-related driving assistance functions, and is preferably activated in the event of a failure of the DC / DC converter and / or sub-networks Grid1, Grid2.

[0095] By constructing at least two redundant subnetworks, Grid1 and Grid2, the low-voltage load L can be powered through multiple electrically separable power supply paths.

[0096] Each subnetwork Grid1, Grid2 has its own switches and lines through which energy can be supplied from the DC / DC converter and / or auxiliary energy storage unit LV to the low-voltage load L. Thus, in the event of a failure of one subnetwork Grid1 or Grid2, the other subnetwork Grid2 or Grid1 can continue to provide power, especially for safety-related driving assistance functions.

[0097] In this way, a fail-safe low-voltage power supply can be achieved, which can support the safe driving capabilities of a vehicle F with a higher level of automation, without the need to force the installation of multiple HV energy storage devices or multiple DC / DC converters, thereby reducing component, packaging costs and expenses.

[0098] During normal operation of the vehicle-mounted electrical network 100, it can be specified that the low-voltage load L and other electrical appliances of the vehicle F can be supplied with electrical energy through the auxiliary energy storage device LV and / or DC / DC converter.

[0099] During normal operation, it can be specified that the DC / DC converter can cover the base load of all low-voltage electrical appliances from the high-voltage battery B. Furthermore, it can be specified that the DC / DC converter can charge the auxiliary energy storage unit LV during normal operation.

[0100] In addition, during normal operation, it is also possible to consider that the auxiliary energy storage unit (LV) can handle short-term power peaks.

[0101] In normal operation, it can also be specified that the DC / DC converter and auxiliary energy storage unit LV can share the load and supply power to low-voltage electrical appliances.

[0102] Other electrical appliances, such as comfort and / or entertainment functions, can also be powered by a combination of auxiliary energy storage (LV) and DC / DC converter during normal operation.

[0103] In the event of a fault in the vehicle-mounted electrical grid 100, it can be specified that only the low-voltage load L is supplied with electrical energy, specifically through the auxiliary energy storage device LV and the DC / DC converter, or only through the auxiliary energy storage device LV and / or only through the DC / DC converter.

[0104] In this way, it is possible to rely on... Figure 1 The switching matrix enables different operating modes, in which low-voltage load L and, if necessary, other low-voltage electrical appliances of vehicle F can be flexibly fed through different power supply paths.

[0105] also, Figure 1 This indicates that in the event of a failure in the affected subnetworks Grid1 and Grid2, the affected subnetworks Grid1 and Grid2 can automatically disconnect.

[0106] Each subnetwork Grid1, Grid2 may be equipped with its own switching element S1_Grid1, S3_Grid1 or S1_Grid2, S3_Grid2, which is opened in case of a fault, thereby electrically isolating the affected subnetwork Grid1, Grid2 from the rest of the vehicle electrical network 100.

[0107] The intact subnetworks Grid1 and Grid2 can continue to draw energy from the DC / DC converter and / or auxiliary energy storage unit LV, so that the safety-related functions on the low-voltage load L can continue to operate reliably.

[0108] also, Figure 1 This indicates that in the event of a DC / DC converter failure, the DC / DC converter can automatically disconnect, specifically from both sub-networks Grid1 and Grid2.

[0109] For this purpose, the vehicle-mounted electrical grid 100 has two switches, S1_Grid1 and S1_Grid2, for the DC / DC converter.

[0110] Switches S1_Grid1 and S1_Grid2 can be set between the output of the DC / DC converter and the corresponding sub-networks Grid1 and Grid2, respectively.

[0111] By using switches S1_Grid1 and S1_Grid2, the connection between the DC / DC converter and sub-networks Grid1 and Grid2 can be controlled in a targeted manner.

[0112] In one operating state, both switches S1_Grid1 and S1_Grid2 can be closed, allowing the DC / DC converter to supply power to the two sub-networks Grid1 and Grid2 in parallel.

[0113] In another operating state, it can be specified that only one of the switches, S1_Grid1 or S1_Grid2, can be closed, so that the DC / DC converter supplies power to only one sub-network, Grid1 or Grid2.

[0114] Switches S1_Grid1 and S1_Grid2 can preferably be constructed as electronic power switches.

[0115] Furthermore, it can be specified that the vehicle-mounted power grid 100 is wired so that in the event of a failure of the auxiliary energy storage device LV, the auxiliary energy storage device LV can automatically disconnect, specifically disconnecting from both sub-networks Grid1 and Grid2.

[0116] For this purpose, the vehicle-mounted power grid 100 has two switches, S3_Grid1 and S3_Grid2, for auxiliary energy storage device LV.

[0117] Switches S3_Grid1 and S3_Grid2 can be set between the output of the auxiliary energy storage unit LV and the corresponding sub-networks Grid1 and Grid2, respectively.

[0118] By using switches S3_Grid1 and S3_Grid2, the connection between the auxiliary energy storage unit LV and the sub-networks Grid1 and Grid2 can be controlled in a targeted manner.

[0119] In one operating state, both switches S3_Grid1 and S3_Grid2 can be closed, allowing the auxiliary energy storage unit LV to supply power to the two sub-networks Grid1 and Grid2 in parallel.

[0120] In another operating state, it can be specified that only one of the switches, S3_Grid1 or S3_Grid2, can be closed, so that the auxiliary energy storage unit LV is powered only by one sub-network, Grid1 or Grid2.

[0121] Switches S1_Grid1, S1_Grid2, S3_Grid1, and S3_Grid2 can preferably be constructed as electronic power switches.

[0122] The combination of switches S1_Grid1 and S1_Grid2 for the DC / DC converter and switches S3_Grid1 and S3_Grid2 for the auxiliary energy storage LV forms a switch matrix, which can be used to realize different power supply combinations.

[0123] Therefore, for example, in the event of a DC / DC converter failure, it can be specified that both switches S1_Grid1 and S1_Grid2 can be open, while both switches S3_Grid1 and S3_Grid2 can be closed, so that only the auxiliary energy storage LV can supply power to the two sub-networks Grid1, Grid2 and / or the selected network Grid1 or Grid2.

[0124] Furthermore, it may be specified that the vehicle-mounted electrical network 100 has (smart) switches configured to identify at least one fault condition and function like a fuse, such as at least one of the following fault conditions: component failure, network failure, overcurrent, voltage state (e.g., including overvoltage and / or undervoltage) and / or incorrect current direction.

[0125] These switches can be equipped with measurement and / or evaluation functions, enabling them to detect electrical parameters such as current, voltage, and current direction and identify fault conditions based on defined thresholds.

[0126] Furthermore, it can be specified that the vehicle-mounted electrical network 100 has, for example, an integrated switch in a power electronic device.

[0127] An integrated switch can be implemented as a semiconductor power switch within a power electronic device that controls the current path within the vehicle's electrical grid 100. This power electronic device can be a component of a DC / DC converter and / or auxiliary battery interface electronics. This power electronic device can provide multiple switching paths for different sub-networks Grid1, Grid2, and load groups.

[0128] In principle, it is conceivable that the DC / DC converter and the auxiliary energy storage LV each have a power electronics device or a common power electronics device, which may, for example, have an integrated switch.

[0129] The power electronics of the DC / DC converter can perform the actual voltage conversion and regulation, while providing an integrated switch through which the output of the DC / DC converter is distributed to sub-networks Grid1 and Grid2.

[0130] The power electronics of the auxiliary energy storage unit LV can control the charging and discharging current, provide protection functions, and regulate the connection with sub-networks Grid1 and Grid2 through an integrated switch.

[0131] Two power electronic devices can be interconnected using signal technology, allowing them to exchange information about load status and fault conditions, and respond to faults in a coordinated manner. A single power electronic device can combine these functions.

[0132] Furthermore, it can be specified that the vehicle-mounted electrical network 100 has a separate switch, which, for example, has its own electronic device.

[0133] Individual switches with their own electronics can be installed as independent components in the vehicle electrical network 100, for example, at critical nodes in the wiring route between the DC / DC converter, the auxiliary energy storage unit LV, and the low-voltage load L. Each such component can provide local measurement and evaluation capabilities and independently decide whether to open or close the switch in the event of a fault.

[0134] also, Figure 1 This indicates that the vehicle electrical network 100 is provided with one, in particular only one housing H, in order to house and / or seal all the components of the vehicle electrical network 100, and / or to provide the vehicle electrical network 100 in the form of a single, operable integrated module.

[0135] The corresponding vehicle F, particularly a hybrid or electric vehicle, preferably an automated to autonomous driving vehicle (which has a corresponding onboard electrical network 100 for powering safety-related driving assistance functions on a low-voltage load L), constitutes another aspect of the invention.

[0136] Safety-related driver assistance functions may have at least one longitudinal guidance function and / or at least one lateral guidance function, such as emergency braking assist, lane keeping assist, spacing assist, speed keeping assist, reversing assist, adaptive brake lights, accident data storage and / or fatigue recognition.

[0137] According to a third aspect, the present invention also relates to the use of a corresponding on-board electrical network 100 for providing at least one safety function, namely:

[0138] —To ensure the safe continued operation of vehicle F,

[0139] —During the transition period, operate vehicle F safely until the driver is able to take over vehicle guidance.

[0140] —Bring vehicle F to a safe stop, for example, by stopping it on the shoulder, and / or

[0141] — Issue an emergency call.

[0142] This application is particularly advantageous in the event of a failure in the vehicle-mounted power grid 100, such as when the sub-network Grid1, Grid2, DC / DC converter, or auxiliary energy storage LV fails.

[0143] According to the fourth aspect, the present invention also relates to an application of a corresponding vehicle-mounted electrical grid 100, namely:

[0144] —Using the auxiliary energy storage device LV to buffer power peaks,

[0145] —Using a DC / DC converter to supply medium loads, and / or

[0146] — Multiple loads are supplied with the help of a DC / DC converter and an auxiliary energy storage unit (LV).

[0147] This application is particularly advantageous when the vehicle-mounted electrical grid 100 is operating normally.

[0148] The foregoing description of the accompanying drawings illustrates the invention by way of example only. Of course, individual features of the various embodiments can be freely combined with each other where technically meaningful, without departing from the scope of the invention as defined by the claims.

[0149] List of reference numerals

[0150] 100 vehicle-mounted power grid

[0151] B Main Energy Storage Unit

[0152] LV Auxiliary Energy Storage

[0153] L low voltage load

[0154] Grid1 first subnet

[0155] Grid2 second subnetwork

[0156] F vehicle

[0157] H casing

[0158] S1_Grid1 Switch / Switch Component

[0159] S1_Grid2 Switch / Switch Component

[0160] S3_Grid1 Switch / Switch Component

[0161] S3_Grid2 Switch / Switch Component

Claims

1. An onboard electrical network (100) for a vehicle (F), particularly a hybrid or electric vehicle, preferably an automated to autonomous vehicle, the vehicle having one, particularly only one, main energy storage device (B), such as a high-voltage battery, like a 400V, 800V, or 1000V battery, for supplying electrical energy to the main electrical appliances of the vehicle (F), such as an electric motor or electric motor. The on-board electrical network (100) includes: One, and particularly only one, DC / DC converter is used to supply electrical energy from the main energy storage unit (B) to a low-voltage load (L), the low-voltage load having, for example, a voltage level of 12V, 24V, or 48V, and One, particularly only one, auxiliary energy storage device (LV), such as a low-voltage battery, like a 12V, 24V, or 48V battery, is used to supply electrical energy to the low-voltage load (L), particularly to supply electrical energy to safety-related driving assistance functions. The vehicle-mounted electrical network (100) is wired to form at least two redundant sub-networks (Grid1, Grid2) to provide fail-safe protection when supplying power to the low-voltage load (L).

2. The vehicle-mounted electrical grid (100) according to claim 1. in, The vehicle electrical network (100) is wired to allow the low-voltage load (L) and other electrical appliances of the vehicle (F) to pass through... —The auxiliary energy storage device (LV) and the DC / DC converter Power is supplied. In particular, it is supplied with electrical energy during the normal operation of the on-board electrical network (100). and / or The on-board electrical network (100) is wired such that only the low-voltage load (L) can pass through. —The auxiliary energy storage device (LV) and the DC / DC converter, —Only the aforementioned auxiliary energy storage device (LV), and / or —Only the DC / DC converters mentioned Power is supplied. In particular, it is supplied with electrical energy in the event of a failure of the on-board electrical grid (100).

3. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The vehicle-mounted electrical network (100) is wired so that the affected subnetworks (Grid1, Grid2) can automatically disconnect in the event of a failure of the affected subnetworks (Grid1, Grid2).

4. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The on-board electrical network (100) is wired such that the DC / DC converter can automatically disconnect in the event of a failure, specifically disconnecting from both sub-networks (Grid1, Grid2). and / or The vehicle-mounted electrical network (100) is wired such that the auxiliary energy storage device (LV) can automatically disconnect in the event of a failure of the auxiliary energy storage device (LV), specifically disconnecting from both sub-networks (Grid1, Grid2).

5. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The vehicle-mounted electrical grid (100) has two switches (S1_Grid1, S1_Grid2) for the DC / DC converter.

6. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The on-board electrical grid (100) has two switches (S3_Grid1, S3_Grid2) for the auxiliary energy storage device (LV).

7. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The on-board electrical network (100) is provided with one, in particular only one, housing (H). In order to accommodate and / or seal all components of the on-board electrical grid (100), And / or to provide the on-board electrical network (100) in the form of a single, independently operable integrated module.

8. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The on-board electrical network (100) has a switch configured to identify at least one fault condition and function as a fuse. For example, it includes at least one of the following fault conditions: —Component failure, —Network failure, —Overcurrent, —Voltage conditions, such as overvoltage and / or undervoltage, and / or —Incorrect current direction.

9. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The vehicle-mounted electrical network (100) has, for example, an integrated switch in a power electronics device.

10. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The DC / DC converter and the auxiliary energy storage (LV) each have a power electronics device or a common power electronics device, which may, for example, have an integrated switch.

11. The vehicle-mounted electrical network (100) according to any one of the preceding claims. in, The vehicle-mounted electrical network (100) has individual switches, each of which has its own electronic device.

12. A vehicle (F), particularly a hybrid or electric vehicle, preferably an automated to autonomous driving vehicle, said vehicle having an onboard electrical network (100) according to any one of the preceding claims for powering safety-related driving assistance functions on a low-voltage load (L).

13. The vehicle (F) according to the preceding claim. in, The safety-related driving assistance function has at least one longitudinal guidance function and / or at least one lateral guidance function, for example: —Emergency braking assist, Lane keeping assist, —Spacing maintenance aid, —Speed ​​maintenance assist, Reversing assist, —Adaptive brake lights, —Accident data storage, and / or — Fatigue recognition.

14. An application of the vehicle-mounted electrical network (100) according to any one of claims 1 to 11 to provide at least one safety function, particularly in the event of a failure of the vehicle-mounted electrical network (100), —Used to ensure the safe continued operation of the vehicle (F), —Used to safely operate the vehicle (F) during the transition period until the driver is able to take over vehicle guidance. —Used to bring the vehicle (F) to a safe stop, for example, on the shoulder, and / or —Used to make an emergency call.

15. An application for using the vehicle-mounted electrical network (100) according to any one of claims 1 to 11 for the following purposes, particularly during the normal operation of the vehicle-mounted electrical network (100): The auxiliary energy storage (LV) is used to buffer power peaks. To supply medium loads using the aforementioned DC / DC converter, and / or Multiple loads are supplied using the DC / DC converter (DC / DC) and the auxiliary energy storage (LV).

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