Method for operating an electrical load in a vehicle

Abstract

The invention relates to a method for operating an electrical load (10) in a vehicle electrical system (1) of a vehicle. The electrical load (10) is supplied with electrical energy via a supply line (12) of the vehicle electrical system (1) from an energy source (7) via a distributor module (9) connected between the energy source (7) and the electrical load (10). The distribution module (9) is provided with at least one converter (15) which converts a voltage from the energy source into a low voltage for the electrical load (10), wherein the converter (15) is used to adjust the voltage (18) according to individual requirements of the electrical load (10), wherein the voltage (18) for the electrical load (10) is varied by means of the converter (15) in order to thus transmit information to the electrical load (10), wherein information is transmitted to the electrical load (10) via a data line (13) of the vehicle electrical system (1), wherein the information is transmitted redundantly with respect to the information to the electrical load (10) via the data line (13) by varying the voltage (18). The invention further relates to a corresponding distribution module (9) and to a vehicle electrical system (1) of a vehicle having at least one such distribution module (9).

Description

[0001] METHOD FOR OPERATING AN ELECTRICAL CONSUMER IN A VEHICLE

[0002] The present invention relates to a method for operating an electrical consumer in a vehicle, a distribution module for an on-board network of a vehicle and an on-board network with such a distribution module.

[0003] Modern vehicles have a multitude of electrical consumers, such as electronic control units, sensors, and the like, which are distributed throughout the vehicle and used to carry out a wide variety of vehicle functions. These electrical consumers are supplied with electrical energy, which is provided, for example, by a central high-voltage drive battery. To distribute the energy, distribution modules can be used in the vehicle, to which several of the electrical consumers are each connected. In order to supply the consumers with a constant low-voltage voltage, for example 12 V, a corresponding DC / DC converter is connected upstream of the distribution modules. If required, additional DC / DC converters can then be provided in the individual control units in order to supply the control unit electronics with the appropriate voltage, for example 5 V or 3.3 V.

[0004] Common distribution modules typically use relays or semiconductor switches (MOSFETs) to supply power to loads. This allows loads to be switched on and off. The supply line to the load is usually protected by a fuse. Conventional fuses are increasingly being replaced in newer systems by electronic fuses, so-called e-fuses. These are semiconductor switches with an adjustable tripping characteristic. However, even with e-fuses, the distribution modules can only switch loads on and off.

[0005] Pulse-width modulation (PWM) is also known for transmitting information to electrical consumers. Pulse-width modulation (PWM) is a technique frequently used in electrical engineering and electronics to control the power supply to electrical consumers. The principle is based on converting an electrical signal into a sequence of pulses. The basic idea is that the power supply to a device is regulated by switching the current on and off at a high frequency. The present invention is based on the object of providing an improved method for operating an electrical consumer in a vehicle.

[0006] This object is achieved according to the teaching of the independent claims. Various embodiments and further developments of the invention are the subject of the dependent claims.

[0007] A first aspect of the invention relates to a method, in particular a computer-implemented method, for operating an electrical consumer in a vehicle's electrical system. The electrical consumer is supplied with electrical energy from an energy source via a supply line of the vehicle's electrical system via a distribution module connected between the energy source and the electrical consumer. At least one converter is provided in the distribution module, which converts a voltage from the energy source (either directly a high-voltage voltage from the energy source or a voltage already reduced by a (centrally) upstream converter (DC / DC converter)) into a low-voltage voltage for the electrical consumer. The voltage is adjusted by means of the converter depending on the individual requirements of the electrical consumer.

[0008] The aforementioned method according to the first aspect is therefore based in particular on the fact that at least one converter, in particular at least one direct current converter (DC / DC converter), is provided in the distribution module. Particularly compared to conventional distribution modules, which, for example, only contain switches or fuses (also known as e-fuses), the input circuitry of electrical consumers connected to the distribution module can be greatly simplified. In particular, the distribution module with integrated converters can stably set a suitable voltage, in particular a low voltage (in particular 12 V, 5 V, or 3.3 V), for the electrical consumers, so that the consumers themselves are no longer required to cope with voltage fluctuations in the vehicle electrical system.In other words, the input circuitry of the consumers is moved to the distribution module so that the individual consumers can be designed more simply, particularly with regard to their input circuitry.

[0009] According to the invention, the distribution module is designed in particular so that the voltage can be adjusted depending on the individual requirements of the electrical consumer. Thus, the converters do not provide a fixed voltage, but can be adjusted according to needs and requirements, even dynamically if necessary, as will be explained in more detail below.

[0010] The term “vehicle” as used herein refers in particular to a passenger car, including all types of motor vehicles, hybrid and battery-powered electric vehicles, as well as vehicles such as vans, buses, trucks, delivery vans and the like.

[0011] The term "electrical load" used here refers in particular to a vehicle's control units, but also to hydraulic or pneumatic or other components, such as sensors and the like, that consume electrical energy and can be controlled electrically. In particular, components of safety-relevant areas of the vehicle, such as the engine control unit, the drive train, or the braking system (especially X-by-Wire), can also be referred to as electrical loads. A redundant control system is usually provided for safety-relevant electrical loads in order to have a second line available for transmitting information and / or control data in the event of a data line failure.

[0012] The term "operation" used here refers in particular to the provision and adjustment of resources necessary for the operation of an electrical consumer. This includes, in particular, the power supply and the transmission of information for control purposes. Both of these processes are generally carried out via the vehicle's electrical system, in particular via the on-board power system with corresponding supply lines for transmitting electrical energy and the on-board communication system with corresponding data lines for transmitting information, such as control data and the like. Communication can take place, in particular, via a bus system (e.g., Controller Area Network, CAN).

[0013] The term "high-voltage" used here, especially in the context of electric vehicles, refers to the vehicle's electrical system, which operates at a higher voltage than the low-voltage electrical system. While the low-voltage electrical system in vehicles typically operates at a voltage of around 12 V (or more generally: no more than 60 V), the high-voltage system uses voltages of up to several hundred volts (e.g., 60 V to 1.5 kV). The high-voltage system in electric vehicles generally includes, in particular, the high-voltage energy storage unit (HV accumulator or HV battery), the electric motor, and other components required to drive the vehicle.

[0014] The term "converter" used here refers specifically to a voltage converter that converts voltage from one voltage level to another, for example, from a higher voltage level to a lower voltage level. Since on-board electrical systems typically use direct current, a converter can also be referred to as a "DC-DC converter" or "DC / DC converter."

[0015] The terms "comprises," "includes," "includes," "has," "has," "with," or any other variation thereof, as used herein, are intended to cover non-exclusive inclusion. For example, a method or apparatus that includes or has a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or that are inherent in such a method or apparatus.

[0016] Furthermore, unless explicitly stated to the contrary, "or" refers to an inclusive "or" and not an exclusive "or." For example, a condition A or B is satisfied by one of the following conditions: A is true (or present) and B is false (or absent), A is false (or absent) and B is true (or present), and both A and B are true (or present).

[0017] The terms "a" or "an" as used herein are defined as "one or more." The terms "another" and "another," and any other variations thereof, are defined as "at least one other."

[0018] The term “plurality” as used here shall mean “two or more”.

[0019] The term “configured” or “set up” to fulfil a specific function (and respective modifications thereof) is to be understood within the meaning of the invention that the corresponding device is already in a design or setting in which it can carry out the function or is at least adjustable - i.e. configurable - so that it can carry out the function after being set accordingly. The configuration can be carried out, for example, by appropriately setting parameters of a process sequence or of switches or the like for activating or deactivating functionalities or settings. In particular, the device can have a plurality of predetermined configurations or operating modes, so that the configuration can be carried out by selecting one of these configurations or operating modes.

[0020] Preferred embodiments of the method are described below, which can be combined with each other as well as with the other aspects of the invention described, unless this is expressly excluded or is technically impossible.

[0021] In some embodiments, the voltage for the electrical load is varied by means of the converter in order to transmit information, such as control data, to the electrical load. Because the converter is provided in the distribution module, it can be used not only to supply voltage to a connected electrical load, but also to transmit information. This is achieved by varying the voltage during operation. It is understood that this occurs within permissible voltage limits. In particular, if a microcontroller of the electrical load is connected directly to the distribution module, information, such as control data, can advantageously be transmitted to the electrical load via the supply voltage.

[0022] In some associated embodiments, the voltage at an input of the electrical load is evaluated by a control device of the electrical load in order to receive the information. Information is therefore received from the electrical load not only via an integrated transceiver, for example, but also via the power supply. The voltage is varied, as just explained, by means of the converter in the distribution module. The control device, e.g., a microcontroller of the electrical load, receives the variable voltage and can evaluate it in order to obtain, in addition to the pure power supply, information or data that can be used for operation, in particular for controlling the electrical load.

[0023] In some embodiments, information is transmitted to the electrical consumer via a data line in the vehicle electrical system, the information being transmitted redundantly to the information via the data line by varying the voltage to the electrical consumer. Redundant communication is particularly advantageous for safety-relevant electrical consumers, such as critical control units. An additional data line is not necessary. As just described, only the voltage at the input of the electrical consumer needs to be evaluated. This provides a simple way to improve reliability. Since no additional lines need to be laid, effort and costs can be reduced. With redundant communication, the same information or control data can be transmitted via the supply voltage as via the actual data line.At least such information or control data can be transmitted via the supply voltage which is necessary for the safe operation of the electrical consumer, especially if communication via the data line fails at least partially.

[0024] In some embodiments, the electrical load is switched from a normal operating mode to a restricted mode or vice versa by varying the voltage. The restricted mode can also be referred to as emergency mode or degradation mode. In particular, non-safety-relevant components (electrical loads) can thus be easily switched to a restricted mode during operation, especially during a malfunction, by varying the supply voltage, for example by means of a short pulse. This can potentially improve or maintain the function of other components, in particular safety-relevant components. Furthermore, by switching the mode via a variation in the supply voltage, no data line is loaded or required, which can also be advantageous for the continued operation of other components.

[0025] In some embodiments, the voltage is varied by superimposing a data signal, in steps, or by pulse sequences, in order to transmit the information to the electrical load. The superimposition can be achieved, in particular, by pulse-width modulation, which allows the transmission of information or control signals via the supply voltage. Simpler commands can also be modulated onto the supply voltage using simple pulses, pulse sequences, or step-like variations.

[0026] In some embodiments, the voltage is adjusted by means of the converter depending on the operating situation of the vehicle and / or the electrical load. In particular, the voltage can be changed depending on the situation during vehicle operation (e.g., while driving). Information can also be transmitted to the electrical load in this way.

[0027] In some embodiments, the converter functions as an electronic fuse. In other words, the converter can be designed in such a way that, in addition to the traditional supply of power to the loads, it also implements the function of a fuse, particularly an electronic fuse ("e-fuse").

[0028] A second aspect of the invention relates to a distribution module for a vehicle's electrical system. The distribution module has at least one converter configured to convert a voltage from a power source into a low-voltage voltage for the electrical load connected to the distribution module and to adjust the voltage depending on the individual requirements of the electrical load. The distribution module is configured, in particular, for operating an electrical load connected to the distribution module according to a method according to the first aspect.

[0029] A third aspect of the invention relates to an on-board electrical system for a vehicle, comprising at least one energy source, a supply line, at least one electrical load, and at least one distribution module according to the second aspect, to which the at least one electrical load is connected. The electrical load is connected to the energy source via the supply line via the distribution module connected between the energy source and the electrical load for supplying electrical energy.

[0030] In some embodiments of the vehicle electrical system, it comprises a converter, in particular a DC / DC converter, which is connected upstream of the at least one distribution module and which is configured to reduce a high-voltage power source. In particular, this converter can be centrally connected upstream of several possible distribution modules. This allows a high-voltage power source to be reduced, for example, to a low-voltage voltage of less than 60 V, which simplifies the design of the distribution modules, particularly compared to a circuit in which the distribution modules are directly supplied with the high-voltage power source.

[0031] In some embodiments of the on-board electrical system, it is divided into several zones, with each zone having at least one distribution module and at least one electrical consumer connected to the respective distribution module. The zones of a vehicle can, for example, include a central zone as well as zones for the front left, front right, rear left, and rear right. Electrical consumers located close to one another, i.e., consumers in a zone, can then be operated via a distribution module. A distribution module can therefore also be referred to as a zone module. This enables decentralized operation of the electrical consumers in a vehicle.

[0032] A fourth aspect of the invention relates to a data processing system comprising at least one processor configured to execute the method according to the first aspect of the invention. The system can, in particular, be integrated into an on-board electrical system according to the third aspect in order to operate at least one electrical load in the on-board electrical system.

[0033] A fifth aspect of the invention relates to a computer program comprising instructions which, when executed on a system according to the fourth aspect, cause the system to carry out the method according to the first aspect.

[0034] The computer program can, in particular, be stored on a non-volatile data carrier. This is preferably a data carrier in the form of an optical data carrier or a flash memory module. This can be advantageous if the computer program as such is to be handled independently of a processor platform on which the one or more programs are to be executed. In another implementation, the computer program can be present as a file on a data processing unit, in particular on a server, and can be downloadable via a data connection, for example the Internet or a dedicated data connection, such as a proprietary or local network. Furthermore, the computer program can have a plurality of interacting individual program modules.

[0035] The system according to the fourth aspect can accordingly comprise a program memory in which the computer program is stored. Alternatively, the system can also be configured to access an external computer program, for example, available on one or more servers or other data processing units, via a communication connection, in particular to exchange data with it that is used during the execution of the method or computer program or that represents outputs of the computer program.

[0036] The features and advantages explained with respect to the first aspect of the invention also apply accordingly to the further aspects of the invention.

[0037] Further advantages, features and possible applications of the present invention will become apparent from the following detailed description in conjunction with the drawings.

[0038] It shows:

[0039] Fig. 1 schematically shows an on-board network of a vehicle according to an embodiment;

[0040] Fig. 2 shows schematically a section of an on-board network;

[0041] Fig. 3 schematically shows a distribution module according to an embodiment;

[0042] Fig. 4 schematically shows an electrical consumer in the form of a control unit; and

[0043] Fig. 5 schematically shows a voltage curve with a signal transmission.

[0044] Throughout the figures, the same reference numerals are used for the same or corresponding elements of the invention.

[0045] Fig. 1 shows a schematic and highly simplified version of an on-board electrical system 1 of a vehicle. The on-board electrical system 1 is divided into a number of zones 2, 3, 4, 5, 6. In the example shown, five zones are provided: a zone 2 at the front right, a zone 3 at the front left, a zone 4 in the middle of the vehicle, a zone 5 at the rear right and a zone 6 at the rear left. By dividing it into zones, the on-board electrical system 1 can be managed in a decentralized manner. This particularly affects the supply of electrical energy, but also the control technology. The electrical energy is provided by a high-voltage energy storage device 7, such as the drive battery of an electric vehicle, and distributed via supply lines 12. The on-board electrical system 1 also includes data lines 13 for communication, i.e. transmission of information, such as control data and the like, from a central control unit 8. In each zone 2, 3, 4, 5, 6, a distribution module 9 is provided, to which electrical consumers 10, such as e.g.B. control units, as well as, for example, sensors 11 are connected. In the example shown, the distribution modules 9 are supplied with a voltage of 12 V (or more generally: with a low voltage of less than 60 V), which is provided by a DC / DC converter 14 (for example, connected centrally in the vehicle electrical system), which reduces the high voltage of the energy storage device 7 (see Fig. 2).

[0046] Conventional distribution modules usually use relays or semiconductor switches (MOSFETs) to switch the loads on and off. The supply line to the load can be protected using a fuse or electronic fuses. In contrast, the distribution modules 9 are each equipped with decentralized DC / DC converters 15 (see Fig. 3) to supply the electrical loads 10. Depending on the load 10 and its individual requirements, the appropriate voltage (12V / 5V / 3.3V) can thus be set in a stable manner. This is particularly advantageous because the electrical loads 10 are no longer required to cope with voltage fluctuations in the vehicle electrical system 1 themselves. Their input circuitry can thus be omitted (or at least greatly simplified). The electrical loads 10 (and in particular their respective control unit 17, e.g.the microcontrollers of control units) are then connected directly to the respective distribution module 9, as illustrated in Fig. 4.

[0047] This type of connection via the DC / DC converters 15 also allows the use of the supply voltage 18 for information transmission (see Fig. 5). An additional data line is then unnecessary. The control unit 17 will simply evaluate the voltage 18 at the input and obtain information, such as control data and the like, from it, thereby enabling redundant communication. This is particularly advantageous for safety-relevant consumers 10. It is understood that the main communication between the central control unit 8 and the electrical consumers 10 takes place via the data line 13, whereby each consumer 10 can be equipped with a corresponding transceiver 16. The DC / DC converters 15 can also assume the function of an electronic fuse (e-fuse).

[0048] Because the voltage can be individually adjusted via the DC / DC converters 15, it is possible to transmit information to the load 10 by superimposing a signal (within the permissible voltage range). For this purpose, the voltage value can, for example, be changed in steps to transmit a corresponding pulse 19. The supply voltage 18 can also be varied by superimposing a signal (voltage pulse, pulse sequence) to transmit information. Signal transmission of this type is, for example, pulse width modulation, logical pulse sequences, or voltage levels. As already mentioned, this thus represents a redundant information channel. By changing the DC voltage depending on the situation during operation (e.g., while driving), information can also be transmitted to the loads 10 in this way.

[0049] An example of transmitting information is sending a specific, simple command to an electrical load 10, for example, to change an operating mode. It is known that a safe power supply is based on the ability to command non-safety-critical functions (components) to a degraded state in order to maintain the supply to the safety-critical loads. A non-safety-critical component can be commanded into a degradation mode via signal transmission by varying the supply voltage 18.

[0050] While at least one exemplary embodiment has been described above, it should be noted that a large number of variations exist. It should also be noted that the described exemplary embodiments are only non-limiting examples and are not intended to limit the scope, applicability, or configuration of the devices and methods described herein. Rather, the foregoing description will provide a guide to implementing at least one exemplary embodiment, with the understanding that various changes in the operation and arrangement of the elements described in an exemplary embodiment may be made without departing from the subject matter defined in the appended claims, as well as their legal equivalents.

[0051] 1 on-board network

[0052] 2 Zone (front right)

[0053] 3 Zone (front left)

[0054] 4 Zone (Middle)

[0055] 5 Zone (rear right)

[0056] 6 Zone (rear left)

[0057] 7 HV energy storage (battery)

[0058] 8 central control unit

[0059] 9 Distribution module (zone module)

[0060] 10 electrical consumers (control unit)

[0061] 11 Sensor

[0062] 12 supply line

[0063] 13 Data line

[0064] 14 DC / DC converters

[0065] 15 DC / DC converters

[0066] 16 transceivers

[0067] 17 Control device (microcontroller control unit)

[0068] 18 Supply voltage

[0069] 19 Voltage pulse

Claims

CLAIMS 1. A method for operating an electrical consumer (10) in an on-board electrical system (1) of a vehicle, wherein the electrical consumer (10) is supplied with electrical energy via a supply line (12) of the on-board electrical system (1) from an energy source (7) via a distribution module (9) connected between the energy source (7) and the electrical consumer (10), wherein at least one converter (15) is provided in the distribution module (9), which converts a voltage from the energy source into a low-voltage voltage for the electrical consumer (10), wherein the voltage (18) is adjusted by means of the converter (15) depending on the individual requirements of the electrical consumer (10), wherein the voltage (18) for the electrical consumer (10) is varied by means of the converter (15) in order to thereby transmit information to the electrical consumer (10),and wherein information is transmitted to the electrical consumer (10) via a data line (13) of the vehicle electrical system (1), wherein the information is transmitted to the electrical consumer (10) by varying the voltage (18) redundantly to the information via the data line (13).

2. Method according to claim 1, wherein the voltage (19) at an input of the electrical consumer (10) is evaluated by means of a control device (17) of the electrical consumer (10) in order to receive the information.

3. Method according to one of the preceding claims, wherein the electrical load (10) is switched from a normal operating mode to a restricted mode or vice versa by varying the voltage (18).

4. Method according to one of the preceding claims, wherein the voltage (19) is varied by superimposing a data signal, in steps or by pulse sequences, in order to thereby transmit the information to the electrical consumer (10).

5. Method according to one of the preceding claims, wherein the voltage (18) is adjusted by means of the converter (15) depending on an operating situation of the vehicle and / or the electrical consumer (10).

6. Method according to one of the preceding claims, wherein the at least one converter (15) functions as an electronic fuse.

7. Distribution module (9) for an on-board electrical system (1) of a vehicle, wherein the distribution module (9) is configured to operate an electrical consumer (10) connected to the distribution module (9), wherein the distribution module (9) has at least one converter (15) which is configured to convert a voltage from an energy source (7) into a low-voltage voltage for the electrical consumer (10) connected to the distribution module (9) and to adjust the voltage (18) depending on individual requirements of the electrical consumer (10) and to vary the voltage (18) for the electrical consumer (10) in order to thereby transmit information to the electrical consumer (10).

8. On-board network (1) for a vehicle, comprising at least one energy source (7), a supply line (12), at least one electrical consumer (10) and at least one distribution module (9) according to claim 7, to which the at least one electrical consumer (10) is connected, wherein the electrical consumer (10) is connected to the energy source (7) via the supply line (12) via the distribution module (9) connected between the energy source (7) and the electrical consumer (10) for supplying electrical energy.

9. On-board network according to claim 8, comprising a converter (14) which is connected upstream of the at least one distribution module (9) and which is designed to reduce a high voltage of the energy source (7).

10. On-board electrical system according to claim 8 or 9, wherein the on-board electrical system (1) is divided into several zones (2, 3, 4, 5, 6), wherein each zone (2, 3, 4, 5, 6) has at least one distribution module (9) and at least one electrical consumer (10) which is connected to the respective distribution module (9).

Images