Method for operating an on-board power supply

Abstract

Method for operating a vehicle electrical system comprising a number of components, wherein at least one quantity is measured for at least one of the number of components, at least one characteristic quantity is calculated from this at least one quantity, the calculated characteristic quantity is compared with a predetermined threshold value, and based on the comparison in a central evaluation unit, it is determined whether the assigned at least one component exhibits anomalous behavior.

Description

[0001] The invention relates to a method for operating an on-board electrical system in a vehicle, in particular a motor vehicle, and an arrangement for carrying out the method. State of the art

[0002] The term "vehicle electrical system" refers to all electrical components in a vehicle. These components include both consumers and energy sources. Consumers are further divided into high-voltage (HV) and low-voltage (LV) consumers, also known as LV consumers (LV: low voltage). It's also important to note that consumers can be either purely comfort-related (i.e., non-safety-relevant) or safety-relevant. For the latter, in particular, the vehicle electrical system must ensure a continuous and reliable power supply.

[0003] It should be noted that most low-voltage (LV) components in vehicles are powered via fuses, which may be located in distribution boxes. These distribution boxes do not contain any monitoring or electronic units. Therefore, current vehicle systems offer no way to verify whether the components' power consumption is within permissible limits. This can only be checked if the monitoring function is integrated into the component itself.

[0004] Due to new assistance systems and safety-related aspects, electronic power distribution units (ePDUs) with integrated control logic are increasingly being used to ensure a reliable power supply for safety-critical equipment. For this purpose, the outputs from the power distribution units are typically implemented with MOSFET switches or electronic fuses, so-called eFuses, which are equipped with current and voltage measurement devices. The ePDUs control their outputs locally based on current or voltage thresholds to isolate the affected areas in the event of a fault. Furthermore, the ePDUs provide a control interface for a higher-level electronic energy management (EEM) system, potentially enabling control of the outputs even during normal operation.

[0005] The publication EP 1 966 020 B1 describes a method for operating a hybrid drive in which several units each generate a target power output determined from the instantaneous state of charge of an electrical energy storage device. The method allows deviations from the target power output depending on the current operating points of the units. Disclosure of the invention

[0006] Against this background, a method according to claim 1 and an arrangement according to claim 7 are presented. Furthermore, a computer program according to claim 9 and a machine-readable storage medium according to claim 10 are presented. Embodiments are described in the dependent claims and in the description.

[0007] The presented method is used to operate an on-board network comprising a number of components. In this method, at least one parameter is measured for at least one of the components, and at least one characteristic parameter is calculated from this parameter. The calculated characteristic parameter is compared to a predefined threshold value, and a central evaluation unit uses this comparison to determine whether the assigned component exhibits anomalous behavior.

[0008] Anomalous behavior is irregular behavior that indicates a component's actions deviate from its intended or regular behavior. The component is therefore not functioning as intended. Comparing the behavior to a threshold value accounts for the fact that, under normal operating conditions, the component's characteristic values ​​typically remain within a certain range. Only when this range is exceeded is the behavior considered anomalous.

[0009] The presented method, through the use of a higher-level, and in particular central, function, detects anomalies in the power consumption of components in a vehicle's electrical system. For this purpose, the power anomalies of the components or consumers are calculated using sensor / measuring units of electronic power distributors and compared with configurable threshold values ​​that define the normal behavior of the components. This normal behavior can be described by characteristic parameters such as maximum / minimum current, maximum / minimum power and / or voltage, activation duration, transmit / receive activity on the communication buses, wake-up cycles, etc.

[0010] The recorded or measured values ​​of the components are thus used for diagnosis, i.e., checking whether abnormal or anomalous behavior is present in the components or the entire vehicle electrical system. Anomaly detection is performed centrally via a higher-level function and not as a local diagnostic function in the respective component.

[0011] The presented method therefore enables the detection of anomalies in the power consumption of components in the vehicle electrical system using electronic power distributors.

[0012] It should be noted that components in a vehicle's electrical system can malfunction, for example, due to software or hardware errors, keeping the vehicle awake even when parked, which can lead to the vehicle breaking down. The presented method typically continuously monitors the behavior of the components in the electrical system and checks for unusual power demands. This makes it possible to detect malfunctions, such as software and hardware anomalies, in order to prevent unwanted discharge of the 12V battery, for example, when the vehicle is parked, and thus avoid vehicle breakdowns or component failures, such as those caused by reduced contact resistance between the positive and negative terminals (known as insulation faults), which leads to increased power consumption and reduced system efficiency (lifespan).Furthermore, by recognizing an increased power demand, energy consumption can be reduced through appropriate measures.

[0013] The current / voltage measurements of the ePDUs and the communication buses are analyzed for each load or component and compared with the corresponding threshold values ​​of the nominal range. If a load deviates from its normal range in its current state, an anomaly in the load behavior is detected, and a "Not OK" (NiO) status is issued for each load. This information can be used by a higher-level energy management (EEM) system to, for example, isolate or reset the faulty loads.

[0014] The proposed method can be used to detect the following anomalies: • increased power consumption during active operation, • increased quiescent current consumption in the parked vehicle, • increased activation frequency, e.g., incorrect use of functions by passengers, • increased feedback through components, • Increased power consumption after FOTA (Firmware Over-The-Air) update, • Entering an undesirable consumer state, • Degradation due to energy management.

[0015] In the presented method, a deviation from the normal behavior of a device is characterized as a device anomaly. It is proposed that the normal behavior of a device be described using characteristic parameters, such as maximum / minimum current / power, maximum / minimum voltage, activation duration, activation frequency, transmit / receive activity on the communication buses, and wake-up cycles. Furthermore, this method allows for the definition of additional parameters for each device.

[0016] For each component, different threshold values ​​are defined depending on the vehicle state (e.g., parked, living, driving) and the component state (e.g., off, sleep mode, active). These threshold values ​​describe the respective normal behavior. This information is stored in the vehicle as a configurable list. The threshold determination can be implemented both in the vehicle and in a cloud environment; see [reference]. Fig. 1. For this purpose, the behavior of components should be learned over a defined period (initial operating time) during vehicle operation and stored as the standard consumption. In another variant, fleet data from different vehicles can be used to reliably learn the standard consumption for the consumers of a vehicle class. Implementation in the cloud requires a bidirectional and cyclical exchange of consumption characteristics or parameters with the vehicle.

[0017] The presented arrangement serves to carry out at least some steps of the procedure described herein and, for this purpose, has an evaluation unit, which is referred to as the central evaluation unit, since it is provided centrally, i.e., at one location, for all components. This can mean that the evaluation unit is located in the vehicle or outside the vehicle, e.g., in a cloud.

[0018] Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawings.

[0019] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention. Brief description of the drawings Fig.Figure 1 shows a possible embodiment of the presented method in a diagram. Fig. Figure 2 shows a possible sequence of the presented procedure in a flowchart. Fig. Figure 3 shows, in a purely schematic and highly simplified representation, a vehicle with an on-board electrical system of the type considered herein. Embodiments of the invention

[0020] The invention is schematically illustrated with reference to embodiments in the drawings and is described in detail below with reference to the drawings.

[0021] Fig.Figure 1 illustrates the operating principle for the detection of consumer anomalies. The diagram shows a vehicle 10 with a function 12 for detecting an anomaly. It also shows an electronic power distribution unit (ePDU) 14, an electrical energy management system (EEM) 16, and a cloud 18. The diagram clarifies two variants: a first variant 20 in the vehicle 10 and a second variant 22 in the cloud 18.

[0022] In the first variant 20, the following steps are carried out: determination of consumer parameters 30, determination of the normal ranges for consumers per vehicle 32, and classification of consumer behavior 34. The parameters processed are: current vehicle condition 36 and current consumer condition per consumer 38.

[0023] According to the second variant 22, step 40 is taken, namely determining the normal ranges for consumers per vehicle segment.

[0024] Arrows illustrate the exchange of data, namely consumer parameters / optimized normal range 50, consumer parameters 52, measured current / voltage per channel / consumer 54, optimized normal range 56 and consumer niO (not OK) 58.

[0025] The procedure is explained in more detail below using a flowchart, with reference to the diagram from Fig. 1.

[0026] In the first step (100), the consumer parameters are determined to ascertain the current behavior of the consumer. For this purpose, the current / voltage measurements from the electronic power distributors (14), the information on the communication bus, the current vehicle state, and the current consumer state are read in. In step (102), this information is forwarded to the cloud to determine an optimized normal range across multiple vehicles. In step (104), the optimized normal ranges are sent to the vehicles at defined intervals, and the current normal range of each vehicle is updated. Depending on the configuration of the electronic power distributors, e.g., the number of outputs, individual consumers or consumer groups can be monitored. The normal range for consumer groups must be derived from the normal ranges of the individual consumers.

[0027] Subsequently, in step 106, the specific consumer behavior is compared with the corresponding normal range. If the consumer's current behavior falls outside these thresholds for a certain period of time, their behavior is classified as a consumer anomaly.

[0028] The normal range for three components can be defined as follows. For each consumer, the minimum / maximum thresholds for current and transmit / receive authorization are considered as an example. These thresholds are defined separately for each vehicle state and consumer state. These states can be expanded or reduced as needed. The AUTOSAR standard can be used as a guide for defining consumer states. Table 1 provides an overview of the assumed states. Vehicle condition Explanation Consumer condition Explanation Park The vehicle is parked and the driver is not in the vehicle. Out of Separate power supply Reside The vehicle is parked and the driver is inside the vehicle. Sleep mode Power supply active and consumers in sleep mode Drive Vehicle readiness ensured and driver in vehicle STANDBY Consumer is ready for operation After the drive (Living -> Parking forx sec) Vehicle is parked, driver is not in vehicle and background functions are active. Active The consumer actively performs at least one function. Charging function active The vehicle is parked, connected to the charging station, and is being charged. Maximum degradation level from energy management The functionality of the consumer is restricted by the energy management system. Pre-treatment function active Vehicle is parked, driver not in vehicle and interior air conditioning is on. Table 1: Definition of vehicle and consumer states

[0029] By defining these states, it is possible to define multiple normal ranges for each consumer. Furthermore, undesired combinations of vehicle and consumer states can be detected. For example, the normal range for the seat heating in the "Parked" state is set to zero using min / max thresholds for the current. This would prevent the assumption of standby or active mode. The "Sleep Mode" state is permitted and is configured with different min / max thresholds. If an increased current is nevertheless measured at the consumer, it means that the consumer has erroneously assumed standby or active mode.

[0030] In contrast, a radar must always be active while driving. Accordingly, the minimum and maximum thresholds are defined as greater than zero. If a lower current is measured, it is classified as an anomaly. Some consumers, such as a steering system, can feed power back into the vehicle's electrical system while in operation. For this, the minimum threshold is set to less than zero to extend the normal range for these consumers.

[0031] In a potential extension of the procedure, the functional state of the consumer must be considered in addition to the vehicle and consumer states. However, the functional state is only relevant for the active consumer state. For this purpose, the normal range in the active state is extended by separate min / max thresholds for each functional state.

[0032] An example of extending the system to include functional consumer states can be provided. Information about the functional state of comfort consumers can be read from the communication buses. For example, the functional states of a seat heater are the different heating levels. Maneuver recognition is required to determine functional states for steering and braking. This maneuver recognition should determine the respective steering / braking maneuver based on available driving behavior information, such as steering angle, brake pedal position, vehicle speed, map data, etc. Consequently, anomalies in power consumption can be detected for each maneuver.

[0033] Fig.Figure 3 shows a highly simplified, schematic representation of a vehicle designated with the reference number 150. This vehicle 150 includes an on-board electrical system 152, which in turn comprises a number of components 154 that can be configured as safety-relevant and / or non-safety-relevant consumers. Electronic power distributors 156 are assigned to the components 154.

[0034] Furthermore, the on-board network 152 includes a central evaluation unit 158, which is designed or equipped to carry out at least a number of steps of the procedure described herein.

[0035] The proposed method can be used in all types of vehicles with integrated, fully electronic power distribution units. Since the method can be implemented in a software product, it can be integrated into a control unit, such as a Vehicle Computer (VCP), Body Control Module (BCM), Powernet Guardian, zone control unit, or an electronic distribution unit, depending on the vehicle concept. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 1 966 020 B1

[0005]

Claims

[1] Method for operating an on-board network (152) comprising a number of components (154) wherein for at least one of the number of components (154) at least one quantity is measured, from which at least one characteristic quantity is calculated, the calculated characteristic value is compared with a predetermined threshold value, and by comparison in a central evaluation unit (158) it is determined whether the assigned at least one component (154) shows anomalous behavior. [2] Method according to claim 1, wherein at least one characteristic parameter is selected from a group consisting of: maximum / minimum current, maximum / minimum power and / or voltage, activation duration, transmit / receive activity on the communication buses, wake-up cycles. [3] Method according to claim 1 or 2, wherein the comparison step is also carried out in the central evaluation unit (158). [4] Method according to one of claims 1 to 3, wherein the central evaluation unit (158) is provided in the vehicle (10, 150). [5] Method according to any one of claims 1 to 3, wherein the central evaluation unit (158) is provided outside the vehicle (10, 150). [6] Method according to any one of claims 1 to 5, wherein the step of measuring the at least one quantity in an electronic load distributor (156) which is associated with the at least one component (154) is carried out. [7] Arrangement for operating a vehicle electrical system (152) with a central evaluation unit (158) which is configured to determine whether a component (154) exhibits anomalous behavior according to any one of claims 1 to 6. [8] Arrangement according to claim 7, to which at least one electronic load distributor (156) is assigned. [9] Computer program with program code means configured to execute a method according to any one of claims 1 to 6 when the computer program is executed on a computing unit, in particular a computing unit in an arrangement according to claim 7 or 8. [10] Machine-readable storage medium with a computer program stored thereon according to claim 9.

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