POWER SUPPLY DEVICE, METHOD FOR SUPPLYING AT LEAST ONE ELECTRICAL CONSUMER AND VEHICLE

Abstract

Energy supply device (102) for a vehicle (100) having a motor (106) for driving the vehicle (100), wherein the energy supply device (102) has the following features: at least one consumer interface (110, 112) for connecting at least one electrical consumer (104, 108) to the power supply device (102); a generator (114) which is mechanically coupled to the motor (106); a battery device (116); a switching device (118) which is designed to electrically connect the generator (114) to the battery device (116) in a normal state in order to charge the battery device (116) and to electrically connect the battery device (116) to the consumer interface (110, 112) in order to supply the consumer (104, 108) with electrical energy, and which is designed to electrically connect the generator (114) to the consumer interface (110, 112) in an emergency state in order to supply the consumer (104, 108) with electrical energy and to electrically disconnect the battery device (116) from the consumer interface (110, 112); and a control device (120) configured to provide a control signal (124) for switching the switching device (118) from the normal state to the emergency state in response to an error signal (126) representing a faulty state of the battery device (116) characterized in that the energy supply device (102) has a voltage regulator (130) which is designed to regulate an electrical voltage provided by the generator (114) without a further battery serving as a buffer, wherein a dynamic range of the voltage regulator (130) is adapted to expected load changes in a power consumption of the consumer (104, 108), and wherein the energy supply device (102) is designed to increase a speed of the engine (106) in idle operation in response to the emergency state.

Description

[0001] The present approach relates to a power supply device, a method for supplying at least one electrical consumer and a vehicle.

[0002] To provide redundant power to a vehicle's on-board network, an additional battery can be planned, or in the case of an electric truck, the voltage can be generated from different cells using a DC / DC converter.

[0003] DE 103 05 357 B4 discloses a vehicle with a device for supplying power to a dual-voltage vehicle electrical system with a starter-generator mechanically coupled to an internal combustion engine. DE 10 2014 219 133 A1 discloses a vehicle with an on-board electrical system with a number of consumers assigned to different safety levels. DE 10 2015 009 490 A1 discloses a method for operating a generator of a motor vehicle, wherein the generator has a separately excited electrical machine with an excitation coil and an active rectifier for generating a rectified output voltage of an alternating voltage generated by the electrical machine. In a normal operating mode, the output voltage is regulated to a predetermined target value. If a battery fault occurs in a battery supporting the output voltage, the output voltage is stabilized.DE 100 20 304 A1 discloses an on-board power supply system with a generator, an on-board power supply battery, electrical consumers and a disconnect switch by means of which the generator and on-board power supply battery can be separated from the rest of the on-board power supply.

[0004] Against this background, the object of the present approach is to create an improved energy supply device, an improved method for supplying at least one electrical consumer and an improved vehicle.

[0005] This object is achieved by a power supply device, a method for supplying at least one electrical consumer and a vehicle according to the main claims.

[0006] The advantages achievable with the presented approach are that a generator already installed in a vehicle can be used additionally to secure the energy supply of a vehicle's electrical system.

[0007] A corresponding energy supply device for a vehicle has the following features: at least one consumer interface for connecting at least one electrical consumer to the power supply device; a generator; a battery device; a switching device which is designed to electrically connect the generator to the battery device in a normal state in order to charge the battery device and to electrically connect the battery device to the consumer interface in order to supply the consumer with electrical energy, and which is designed to electrically connect the generator to the consumer interface in an emergency state in order to supply the consumer with electrical energy and to electrically disconnect the battery device from the consumer interface; and a control device configured to provide a control signal for switching the switching device from the normal state to the emergency state in response to an error signal representing a faulty state of the battery device.

[0008] The vehicle can be a passenger vehicle or a truck. The energy supply device can be an on-board electrical system of the vehicle or part of such an on-board electrical system. The electrical consumer can be, for example, a control unit, a sensor, or an electric motor of the vehicle. The battery device can comprise at least one battery. The battery device can be used to provide the electrical energy required to operate the electrical consumer. The generator can be coupled to a motor, for example an internal combustion engine of the vehicle, and used to provide electrical energy to be fed into the battery. The normal state can represent a state of the energy supply device in which the battery device can provide sufficient electrical energy.The emergency state can represent a state of the energy supply device in which a sufficient energy supply via the battery device is not guaranteed, for example because the battery device has a fault. The switching device can comprise a plurality of electrical switches, for example in the form of power transistors. In the normal state, the switching device can be designed to connect electrical lines of the energy supply device such that the electrical consumer is supplied with electrical energy from the battery device. In the emergency state, however, the switching device can be designed to connect the electrical lines of the energy supply device such that the electrical consumer is supplied with electrical energy directly from the generator.In this case, the battery device can be electrically isolated from both the generator and the electrical load, with a ground connection to the generator and / or the electrical load optionally remaining. Thus, an electrical circuit can be broken. The control device can be part of the switching device or implemented externally to the switching device. The control device can comprise a sensor for detecting the faulty state of the battery device or can be coupled to such a sensor.

[0009] According to one embodiment, the battery device can comprise two batteries connected in series. Such a series connection is frequently found in trucks, for example. Two batteries connected in series are particularly necessary for 24 V on-board electrical systems, such as those found in trucks. Passenger cars typically have only one 12 V battery installed, or two separate batteries not connected in series, one of which serves only as a starter battery, the other for the remaining consumers.

[0010] The generator may have a generator shaft for coupling the generator to a vehicle engine. For example, the generator may be coupled to an engine shaft via a V-belt. Thus, a generator such as is typically used in vehicles equipped with an internal combustion engine can be used.

[0011] The energy supply device can have a voltage regulator that is designed to regulate an electrical voltage provided by the generator. In this case, a dynamic range of the voltage regulator can be adapted to expected load changes in the power consumption of the consumer. Advantageously, a corresponding voltage regulator is typically already installed in vehicles comprising a generator. Since the electrical consumer is supplied directly by the generator, it is advantageous that the dynamic range of the voltage regulator is adapted to voltage fluctuations that can be expected during operation of the vehicle. For this purpose, the voltage regulator can, for example, comprise sufficiently large capacitors. Advantageously, the voltage regulator can be designed to regulate the voltage without the presence of an additional battery serving as a buffer.

[0012] The switching device can be configured to electrically disconnect the battery device from the generator in the emergency state. This can, for example, prevent further damage to the battery device or prevent energy loss, for example, through a short circuit.

[0013] The control device can be configured to provide a shutdown signal for shutting down at least one load in response to the error signal. This can reduce the load on the generator. For example, a non-safety-relevant load is suitable for shutdown.

[0014] The power supply device may comprise a fault detection device configured to detect the faulty state of the battery device. Furthermore, the fault detection device may be configured to provide the fault signal when the faulty state is detected. For example, the fault detection device may comprise a voltmeter.

[0015] The switching device can comprise a generator connection for connecting the switching device to the generator, at least one first load connection for connecting the switching device to a first load interface, a first battery connection and a second battery connection for connecting the switching device to the battery device, and at least one second load connection for connecting the switching device to a second load interface. In this way, the switching device can be arranged between the generator, the battery device, and the load such that the switching device can disconnect or interrupt relevant electrical lines between the generator, the battery device, and the load, depending on whether the normal state or the emergency state exists.

[0016] The energy supply device can advantageously be used in a vehicle. In addition to the aforementioned energy supply device, a corresponding vehicle comprises a motor for driving the vehicle and at least one electrical load. The motor can be mechanically coupled to the generator of the energy supply device, and the at least one electrical load is electrically connected to the at least one load interface of the energy supply device.

[0017] The electrical load can be embodied as a control unit for a safety-critical electrical load and / or as a starter for the engine. For example, the electrical load can be embodied as a control unit for a braking system and / or as a control unit for automated vehicle control. Advantageously, this allows the loads required for safe operation of the vehicle to be reliably supplied with electrical energy even if the battery device is faulty.

[0018] The engine can be configured to provide a first kinetic energy in idle operation. Typically, the kinetic energy provided in idle operation is less than the energy provided to drive the vehicle. The generator can be configured to use the first kinetic energy to provide a first electrical energy that corresponds to a maximum energy consumption of the at least one consumer. The generator can be dimensioned accordingly for this purpose. In this way, the electrical consumer, or at least the electrical consumer(s) to be supplied in an emergency state, can be supplied with sufficient electrical energy even when the vehicle is stationary.

[0019] Optionally, an adaptive increase in the idle speed can be performed in this fault state to meet the energy demand in the electrical system. For this purpose, the energy supply device can be configured to increase the engine speed in idle mode in response to the emergency state. Thus, an adaptive increase in the speed can occur during the fault state.

[0020] A corresponding procedure includes the following steps: Electrically connecting the generator to the battery device to charge the battery device, and electrically connecting the battery device to a load interface to supply the load with electrical energy in response to a fault-free state of the battery device; and Electrically connecting the generator to the load interface to supply electrical energy to the load, and electrically disconnecting the battery device from the load interface in response to a faulty condition of the battery device.

[0021] For example, in response to the faulty condition, the vehicle's automatic start-stop system can be blocked.

[0022] For example, the steps of the method can be implemented using a switching device mentioned.

[0023] Examples of the approach presented here are explained in more detail in the following description with reference to the figures. They show: Fig. 1 is a schematic representation of a vehicle with a power supply device according to an embodiment; and Fig. 2 a flowchart of a method for supplying at least one electrical consumer according to an embodiment.

[0024] In the following description of advantageous embodiments of the present approach, the same or similar reference numerals are used for the elements shown in the various figures and having a similar effect, whereby a repeated description of these elements is omitted.

[0025] Fig. 1 shows a schematic representation of a vehicle 100 with an energy supply device 102 according to an exemplary embodiment. For example, the vehicle 100 is a truck. The vehicle 100 has at least one electrical consumer 104, typically a plurality of electrical consumers. For example, the electrical consumer 104 is a control unit for a braking system of the vehicle 100 or a control unit for controlling a functionality of the vehicle 100. Such a control unit can also be, for example, a control unit for the automated control of the vehicle 100 or, generally, a control unit for an electrical consumer of the vehicle 100. Furthermore, the vehicle 100 has an engine 106. For example, the engine 106 is designed as a drive motor for propelling the vehicle 100. This can be, for example, an internal combustion engine.In this case, the vehicle has another electrical load 108 in the form of a starter for starting the engine 106. The electrical loads 104, 108 require electrical energy for their operation. This electrical energy is provided by the power supply device 102 via at least one load interface, according to this exemplary embodiment, via a first load interface 110 and a second load interface 112.

[0026] According to this embodiment, the energy supply device 102 comprises a generator 114, a battery device 116, a switching device 118 and a control device 120.

[0027] The battery device 116 comprises at least one battery 122, according to this exemplary embodiment optionally two batteries 122 connected in series. For example, the batteries 122 are each a 12 V, 225 Ah, 1150 A battery, as is typically used in vehicles. If the vehicle 100 is designed as a passenger car, the battery device 116 typically does not comprise two batteries connected in series. In the fault-free state of the battery device 116, the battery device 116 is designed to supply the at least one electrical consumer 104, 108 with electrical energy. This is also referred to as the normal state. In a faulty state of the battery device 116, the battery device 116 may not be able to provide sufficient electrical energy to supply an electrical consumer 104, 108. This state is also referred to as the emergency state.In this case, the energy supply device 102 is designed to provide the required electrical energy for supplying the at least one electrical consumer 104, 108 directly from the generator 114, bypassing the battery device 116.

[0028] The generator 114 is mechanically coupled to the engine 106; for example, a generator shaft of the generator 114 is connected to a motor shaft of the engine 106 via a V-belt. In this way, when the engine 106 is operating, the kinetic energy provided by the engine 106 can be converted into electrical energy by the generator 114. In the normal state, the electrical energy provided by the generator 114 is fed into the battery device 116 so that the batteries 122 can be charged. In emergency operation, the electrical energy provided by the generator is used to supply at least one of the electrical loads 104, 108.

[0029] The switching device 118 is designed to ensure a power supply to the electrical consumers 104, 108 via the battery device 116 or the generator 114, depending on whether the normal state or the emergency state is present. When the normal state is present, the switching device 118 is designed to electrically connect the generator 114 to the battery device 116. This allows the battery device 116 to be charged or recharged. Furthermore, the switching device 118 is designed to electrically connect the battery device 116 to the second consumer interface 112 in the normal state. This allows the at least one electrical consumer 104, 108 to be supplied with electrical energy directly from the battery device 116.In the emergency state, the switching device 118 is designed to electrically connect the generator 114 to the second load interface 112, bypassing the battery device 116. As a result, the at least one electrical load 104, 108 is supplied with power directly from the generator 114. Furthermore, the switching device 118 is designed to electrically disconnect the battery device 116 from the second load interface 112. Optionally, the switching device 118 is designed to electrically disconnect the battery device 116 from the generator during emergency operation.

[0030] The control device 120 is designed to switch the switching device 118 between the normal state and the original state. For this purpose, the control device 120 is designed to provide a corresponding control signal 124 to the switching device 118. According to one embodiment, the control device 120 is designed to provide a control signal 124 suitable for switching the switching device 118 from the normal state to the emergency state in response to an error signal 126 representing a faulty state of the battery device 116. Optionally, the control device 120 is designed to provide a control signal 124 suitable for switching the switching device 118 from the emergency state to the normal state in response to a signal representing a fault-free state of the battery device 116.

[0031] Optionally, the energy supply device 102 comprises an error detection device 128 configured to detect the faulty state of the battery device 116 and to provide the error signal 126 indicating the faulty state. For this purpose, the error detection device 128 is coupled to the battery device 116 in a suitable manner. For example, the error detection device 128 is configured to detect a short circuit within the battery device 116 or an output voltage of the battery device 116 that is below a specification as the faulty state.

[0032] According to one embodiment, the energy supply device 102 comprises a voltage regulator 130 configured to regulate a voltage provided by the generator 114. Optionally, the voltage regulator 130 is configured, at least in emergency operation, to regulate the voltage provided by the generator 114 such that the provided voltage adapts to expected load changes in the power consumption of at least one consumer, which is supplied with electrical energy directly by the generator 114 during emergency operation. For this purpose, according to one embodiment, a dynamic range of the voltage regulator 130 is configured to correspond to the expected load change.

[0033] Optionally, the control device 120 is configured to provide a shutdown signal 132 for shutting down at least one load 104, 108 in emergency operation. For example, the control device 120 is configured to provide the shutdown signal 132 in response to the error signal 126. This has an advantageous effect on the required dynamic range of the voltage regulator 130.

[0034] According to one embodiment, the generator 114 is designed with respect to its power such that a kinetic energy of the engine 106 operated in idle mode, which is coupled into the generator 114, is sufficient to provide sufficient electrical energy to be able to meet a maximum energy consumption of the at least one electrical consumer to be supplied in emergency mode.

[0035] According to the exemplary embodiment shown, the switching device 118 has a generator connection 140, for example two first load connections 142, a first battery connection 144, at least one second battery connection 146, here for example three separate second battery connections 146, and at least one second load connection 148, for example three second load connections 148. The generator 114 is connected to the generator connection 140 and optionally to the starter 108 via an electrical line. The at least one electrical load 104 is connected to the first load connection 142 via an electrical line and optionally a fuse device 150, here an intermediate fuse box. According to this exemplary embodiment, two electrical lines are shown, for example for connecting two separate electrical loads 104 to the two first load connections 142 shown.The first battery terminal 144 is connected via an electrical line to a first pole of the battery device 116, and the second battery terminal(s) 146 are connected via one or more electrical lines to a second pole of the battery device 116. According to the exemplary embodiment shown, one of the second consumer terminals 148 is connected via an electrical line to the starter 108 and optionally to the engine 106, another second consumer terminal 148 is connected via an electrical line to the electrical consumer 104, and another second consumer terminal 148 is connected via an electrical line to a further electrical consumer 104. According to this exemplary embodiment, the first consumer interface 110 comprises the first consumer terminals 142 and optionally the generator terminal 140, and the second consumer interface 112 comprises the second consumer terminals 148.

[0036] According to one embodiment, the switching device 118 is configured to connect the generator terminal 140 and the first load terminals 148 to the first battery terminal 144 in the normal state. Furthermore, the switching device 118 is configured to connect the second battery terminal(s) 146 to the second load terminals 148 in the normal state. Furthermore, the switching device 118 is configured to interrupt a direct electrical connection between the generator terminal 140 and the second load terminals 148, for example, via a connecting line 151.

[0037] According to one embodiment, the switching device 118 comprises a battery switch 152, to which the generator terminal 140 and the first load terminals 148 are assigned. Furthermore, the switching device 118 optionally comprises a further battery switch 154, to which the second battery terminals 146 and the second load terminals 148 are assigned. The battery switches 152, 154 can also be implemented as a common circuit comprising a plurality of switches for connecting the terminals 140, 142, 144, 146, 148.

[0038] According to one embodiment, the switching device 118 is configured to interrupt an electrical connection between the generator terminal 140 and the first load terminals 142 with the first battery terminal 144 in the emergency state. Additionally or alternatively, the switching device 118 is configured to interrupt an electrical connection between the second battery terminal 146 and the second load terminals 148 in this state. Furthermore, the switching device 118 is configured to connect the generator terminal 140 directly, for example via the connecting line 151, to the second load terminals 148 in order to enable a direct power supply to the electrical loads 104, 108 via the generator 114.

[0039] According to one exemplary embodiment, vehicle 100 has a redundant on-board electrical system with an exclusive supply via generator 114. Creating redundancies is necessary, or at least expedient, for example, in the course of automated or autonomous driving of vehicles of all kinds. These redundancies must be designed such that vehicle 100 cannot enter a safety-critical or uncontrollable state. Thus, systems such as the electric braking system EBS or ABS (anti-lock braking system), which are indicated by way of example by the at least one electrical consumer 104, are installed multiple times in vehicle 100. To prevent a single fault from leading to a chained failure, the power supplies of the control units, such as the at least one electrical consumer 104, are designed to be sufficiently independent.According to the described approach, it is advantageously not necessary to plan for an additional battery or, in the case of an electric truck as vehicle 100, to generate the voltage from different cells using a DC / DC converter. Instead, the fact that the generator 114 has the same voltage source characteristics as a battery is exploited.

[0040] Advantageously, the described approach can be implemented by slightly adapting a conventional wiring configuration in an on-board electrical system. According to one exemplary embodiment, the following system-level adaptations are required: The dynamics of the voltage regulator 130 of the generator 114 are sufficient to cope with the current changes of the consumers 104, 108 in the emergency state, also referred to as standalone operation.

[0041] The battery switch 152 opens its contacts in the event of a fault in at least one battery 122, i.e. in an emergency state.

[0042] The output current of generator 114 covers the power requirements of consumers 104, 108 at idle. If necessary, non-safety-relevant auxiliary consumers are shut down. Optionally, the speed of engine 106 is increased during idle operation during the fault condition to ensure a sufficient power supply.

[0043] Safety-relevant consumers, such as a speedometer, are connected behind the battery switch 152 so that they continue to be supplied with power when disconnected.

[0044] Fig. 2 shows a flowchart of a method for supplying at least one electrical load according to an embodiment. The method can be used, for example, in connection with the Fig. 1 described energy supply device.

[0045] The method can increase the availability of the vehicle electrical system insofar as the electrical consumers, for example in the form of control units with a possibly degraded voltage quality and / or increased ripple, can still stably supply the logic and / or sensors / actuators.

[0046] Upon response or during a fault-free state of the battery device, the generator is electrically connected to the battery device in a step 201. In addition, the battery device is electrically connected to a load interface in order to supply the load with electrical energy.

[0047] Upon activation or during a faulty state of the battery device, the generator is electrically connected to the load interface in a step 203 to supply the load with electrical energy. Furthermore, the battery device is electrically disconnected from the load interface. Comfort / efficiency functions that shut down the combustion engine are deactivated for this emergency mode, for example, to allow the vehicle to drive to the nearest workshop without relying on the starter battery. LIST OF REFERENCE SYMBOLS 100 vehicles 102 Power supply device 104 electrical consumers 106 Engine 108 starters 110 first consumer interface 112 second consumer interface 114 Generator 116 Battery device 118 Switching device 120 Control device 122 Battery 124 control signal 126 Error signal 128 Error detection device 130 voltage regulators 132 shutdown signal 140 generator connection 142 first consumer connection 144 first battery connection 146 second battery connection 148 second consumer connection 150 fuse box 151 connecting line 152 Battery switch 154 additional battery switches 201 Step of connecting 203 Step of connecting and disconnecting

Claims

[1] Energy supply device (102) for a vehicle (100) having a motor (106) for driving the vehicle (100), the energy supply device (102) having the following features: at least one consumer interface (110, 112) for connecting at least one electrical consumer (104, 108) to the power supply device (102); a generator (114) which is mechanically coupled to the motor (106); a battery device (116); a switching device (118) which is designed to electrically connect the generator (114) to the battery device (116) in a normal state in order to charge the battery device (116) and to electrically connect the battery device (116) to the consumer interface (110, 112) in order to supply the consumer (104, 108) with electrical energy, and which is designed to electrically connect the generator (114) to the consumer interface (110, 112) in an emergency state in order to supply the consumer (104, 108) with electrical energy and to electrically disconnect the battery device (116) from the consumer interface (110, 112); and a control device (120) configured to provide a control signal (124) for switching the switching device (118) from the normal state to the emergency state in response to an error signal (126) representing a faulty state of the battery device (116) characterized by , that the energy supply device (102) has a voltage regulator (130) which is designed to regulate an electrical voltage provided by the generator (114) without a further battery serving as a buffer, wherein a dynamic range of the voltage regulator (130) is adapted to expected load changes in a power consumption of the consumer (104, 108), and wherein the energy supply device (102) is designed to increase a speed of the engine (106) in idle operation in response to the emergency state. [2] The power supply device (102) of claim 1, wherein the battery means (116) comprises a single battery (122) or two batteries (122) connected in series. [3] Energy supply device (102) according to one of the preceding claims, wherein the generator (114) has a generator shaft for coupling the generator (114) to the engine (106) of the vehicle (100). [4] Energy supply device (102) according to one of the preceding claims, wherein the switching device (118) is designed to electrically disconnect the battery device (116) from the generator (114) in the emergency state. [5] Energy supply device (102) according to one of the preceding claims, wherein the control device (120) is designed to provide a shutdown signal (132) for switching off at least one consumer (104, 108) in response to the error signal (126). [6] Energy supply device (102) according to one of the preceding claims, comprising an error detection device (128) which is designed to detect the faulty state of the battery device (116) and to provide the error signal (126). [7] Energy supply device (102) according to one of the preceding claims, wherein the switching device (118) comprises a generator connection (140) for connecting the switching device (118) to the generator (114), at least one first load connection (142) for connecting the switching device (118) to a first load interface (110), a first battery connection (144) and a second battery connection (146) for connecting the switching device (118) to the battery device (116), and at least one second load connection (148) for connecting the switching device (118) to a second load interface (112). [8] Vehicle (100) with the following characteristics: a power supply device (102) according to one of the preceding claims; the motor (106) for driving the vehicle (100), wherein the motor (106) is mechanically coupled to the generator (114) of the energy supply device (102); at least one electrical consumer (104, 108) which is electrically connected to the at least one consumer interface (110, 112) of the energy supply device (102). [9] Vehicle (100) according to claim 8, wherein the electrical consumer (104, 108) is designed as a control unit for a safety-critical electrical consumer of the vehicle (100) and / or as a starter for the engine. [10] Vehicle (100) according to claim 8 or 9, wherein the motor (106) is designed to provide kinetic energy in the idle operation and the generator (114) is designed to provide electrical energy using the kinetic energy, which corresponds to a maximum energy consumption of the consumer (104, 108). [11] Method for supplying at least one electrical consumer (104, 108) of a vehicle (100) comprising a generator (114) and a battery device (116) with electrical energy, wherein the vehicle (100) has a motor (106) for driving the vehicle (100) and the generator (114) can be coupled to the motor (106), and wherein the method comprises the following steps: Connecting (201) the generator (114) electrically to the battery device (116) to charge the battery device (116), and connecting the battery device (116) electrically to a consumer interface (110, 112) to supply the consumer (104, 108) with electrical energy in response to a fault-free state of the battery device (116); and Connecting (203) the generator (114) electrically to the load interface (110, 112) to supply the load (104, 108) with electrical energy, and electrically disconnecting the battery device (116) from the load interface (110, 112) in response to a faulty condition of the battery device (116); characterized by , that an electrical voltage provided by the generator (114) is regulated using a voltage regulator (130) without an additional battery serving as a buffer, wherein a dynamic range of the voltage regulator (130) is adapted to expected load changes in a power consumption of the consumer (104, 108), and in response to the faulty state of the battery device (116), a speed of the engine (106) in the idle mode is increased. [12] Method according to claim 11, wherein the step (203) comprises blocking an automatic start-stop system of the vehicle (100).

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