Triggering of a safety battery terminal

Abstract

Control unit (104) for a vehicle, wherein the vehicle comprises a power line (103) which is connected to a battery (102) of the vehicle via a safety battery terminal (101); wherein the control unit (104) is configured, - to detect a vehicle accident; - to determine one or more indications of an impairment of the vehicle's power supply from the battery (102) based on measurement data taken directly at the control unit (104); - to immediately open the safety battery terminal (101) upon detection of the accident if, based on one or more indicators, it is determined that the power line (103) is damaged; and - to delay the opening of the safety battery terminal (101) to disconnect the power line (103) from the battery (102) if, based on one or more indications, it is determined that there is no damage to the power line (103).

Description

[0001] The invention relates to the power supply of a vehicle during and / or after an accident. In particular, the invention relates to the provision of electrical energy by a vehicle battery after an accident has been detected by a control unit of the vehicle.

[0002] Vehicles have numerous electrical components, some of which, due to their high energy consumption, are directly connected to the vehicle's battery via a battery connection cable. This battery connection cable is typically connected to the battery using a safety battery terminal (SBK). The battery can be a low-voltage battery (e.g., a 12V battery) in a vehicle with an internal combustion engine and / or a high-voltage battery in a hybrid or electric vehicle. In the event of an accident, the SBK is triggered or opened, thereby interrupting the electrical connection between the battery connection cable and the battery. Triggering or opening the SBK is intended to prevent the risk of a short circuit in the battery connection cable.

[0003] On the other hand, disconnecting the battery connection cable from the battery means that the consumers supplied via the battery connection cable are no longer supplied with power and are therefore no longer available after ignition of the SBK.

[0004] DE 10 2012 018 338 A1 describes a device for deactivating high-voltage components of a vehicle. JP 2006-197 775 A describes a control unit for a vehicle. DE 10 2012 204 788 A1 describes a control device for an electric vehicle with a high-voltage electrical system.

[0005] This document addresses the aforementioned technical problems. In particular, it describes a method and a corresponding device that can ensure the power supply to consumers connected via the battery connection cable, even after an accident has been detected. At the same time, the methods and devices described in this document also eliminate the risk of a short circuit in the battery connection cable.

[0006] According to one aspect, a control unit for a vehicle (e.g., for a passenger car, truck, or automobile) is described. The control unit can, for example, include an airbag control unit, which is configured to trigger one or more airbags and / or one or more seatbelt pretensioners of the vehicle after detecting a crash.

[0007] The vehicle includes a power cable that is connected to the vehicle's battery via a safety battery terminal. As mentioned above, the battery can be a conventional battery (e.g., a 12V battery) and / or a high-voltage battery (e.g., for hybrid vehicles). The power cable can supply one or more of the vehicle's electrical components (e.g., a starter motor and / or an electronic control unit) with electrical energy. For example, the electronic control unit itself can also be powered by the vehicle's battery via this power cable. The power cable may include a battery charging cable.

[0008] The control unit is designed to detect vehicle accidents. To do this, the control unit can receive sensor data from various sensors on the vehicle. Furthermore, the control unit can register the time of the accident, i.e., the point in time at which the vehicle accident was detected by the control unit.

[0009] The control unit can be further configured to detect one or more indicators of a disruption to the vehicle's power supply, either from or to the battery. In other words, it can detect one or more indicators of whether the vehicle's electrical power supply from the battery is impaired. Specifically, it can detect one or more indicators of a disruption to the control unit's own power supply. These indicators can be determined directly at the control unit, specifically based on measurement data obtained directly from the unit. This ensures the timely detection of these indicators.The one or more indicators may include, for example, the level of the control unit's supply voltage (especially if the control unit is powered via the power line). The control unit's supply voltage can typically be measured directly at an input pin of the control unit.

[0010] Alternatively or additionally, the control unit can be configured to determine the voltage level on the power line. For this purpose, the control unit can include a measuring line with which the voltage level on the power line can be measured.

[0011] The control unit may include an intermediate storage device (e.g., a capacity) to provide temporary energy autonomy independent of the battery. Alternatively or additionally, one or more indicators may suggest that the control unit's energy supply is at least partially provided by the intermediate storage device. This information can also typically be measured directly at the control unit.

[0012] The control unit can be configured to determine, based on one or more indicators, whether or not the power line is damaged. In other words, the control unit can decide, based on one or more indicators, whether or not the power line is damaged. Specifically, the control unit can be configured to determine that no power line damage exists if the supply voltage level is equal to or greater than a predefined voltage threshold, and / or if the voltage level on the power line is equal to or greater than a predefined voltage threshold, and / or if the voltage on the power line exhibits predefined characteristic voltage disturbances (e.g., patterns).In particular, the control unit can be configured to determine the voltage profile on the power line over time and compare it to one or more predefined characteristic voltage disturbances (e.g., voltage waveform patterns or reference voltage waveforms). If one of the predefined characteristic voltage disturbances is detected, this can be interpreted as an indication that the power line is damaged. Conversely, if none of the predefined characteristic voltage disturbances are detected, this can be interpreted as an indication that the power line is not damaged. Alternatively or additionally, the control unit can be configured to determine that no power line damage is present if a proportion of the control unit's power supply supplied via the buffer is equal to or less than a predefined threshold value.

[0013] In one example, the control unit is configured to determine that there is no damage to the power line (only) if both the supply voltage level is equal to or greater than the predefined voltage threshold (and / or if the voltage level on the power line is equal to or greater than the predefined voltage threshold and / or if the voltage on the power line does not exhibit one or more predefined characteristic voltage disturbances (e.g., patterns)), and if the proportion of the control unit's power supply supplied via the buffer is equal to or less than the predefined proportion threshold. If both of these indicators are not present, the control unit may be configured to determine that there is damage to the power line.

[0014] The control unit can be further configured, depending on the one or more indicators determined, to at least delay the activation or opening of the safety battery terminal to disconnect the power cable from the battery (compared to the registered time of the accident). As explained above, the control unit can determine, based on the one or more indicators, whether or not there is damage to the power cable. Opening the safety battery terminal to disconnect the power cable from the battery can be delayed if, based on the one or more indicators, it is determined that there is no damage to the power cable. Conversely, if, based on the one or more indicators, it is determined that there is damage to the power cable, the control unit can be configured to activate or open the safety battery terminal immediately upon detection of the accident (i.e., at the time of the accident).Opening the safety battery terminal typically results in a physical separation between the battery and the power line, thus interrupting the flow of current on the power line.

[0015] A controlled, delayed opening of the safety battery terminal ensures that electrical devices connected to the battery via the power line can continue to function (e.g., for data storage) even after an accident. Simultaneously, by considering one or more indicators of a possible impairment of the vehicle's power supply by the battery, it is ensured that there is no risk of short circuits.

[0016] The control unit can be configured to delay the opening of the safety battery terminal by a predefined time interval (starting from the registered time of the accident). After the predefined time interval has elapsed, the safety battery terminal can then be opened by the control unit.

[0017] The vehicle can include one or more electrical consumers that are supplied with power via the power line. In particular, the vehicle can include a second control unit that is supplied with power via the power line. The predefined time interval (for the delayed release of the safety battery terminal) can be long enough to allow the second control unit to complete final tasks (such as saving data). For example, the predefined time interval can be long enough to allow a controlled shutdown of the second control unit and / or to allow data (e.g., diagnostic data) to be saved.

[0018] The control unit can be configured to repeatedly detect one or more indicators regarding impairment of the vehicle's power supply by or from the battery during a predefined time interval (starting from the time of the accident). In other words, the one or more indicators can be repeatedly detected (e.g., at a predefined frequency) after the accident is detected and before the predefined time interval expires. This allows for repeated determination during the predefined time interval of whether or not the electrical wiring is damaged. Depending on the repeatedly detected one or more indicators, the control unit can be configured to activate or open the safety battery terminal before the predefined time interval expires.In particular, the safety battery terminal can be opened as soon as it is determined, based on one or more indicators, that the power line is damaged. This ensures that any short-circuit risks that may arise in the meantime are taken into account and immediately prevented.

[0019] According to another aspect, a vehicle is described that includes the control unit described in this document.

[0020] Furthermore, a procedure is described that is executed, for example, by the control unit described in this document. The procedure may include features corresponding to those of the described control unit. In particular, a procedure for controlling a safety battery terminal for a vehicle is described. The vehicle includes a power line that is connected to the vehicle's battery via the safety battery terminal. The procedure includes detecting a vehicle accident. Furthermore, after detecting an accident, the procedure includes determining one or more indicators of a disruption to the power supply from the battery. Based on these one or more indicators, it can then be determined whether or not the power line is damaged.Depending on one or more indicators, opening the safety battery terminal to disconnect the power cable from the battery may be delayed. In particular, opening the safety battery terminal to disconnect the power cable from the battery may be delayed if, based on one or more indicators, it is determined that there is no damage to the power cable.

[0021] Another aspect described is a software (SW) program. The SW program can be configured to run on a processor and thereby execute the procedure described in this document.

[0022] Another aspect describes a storage medium. This storage medium can include a software program configured to run on a processor and thereby execute the procedure described in this document.

[0023] It should be noted that the methods, devices, and systems described in this document can be used both alone and in combination with other methods, devices, and systems described in this document. Furthermore, any aspect of the methods, devices, and systems described in this document can be combined with one another in a variety of ways. In particular, the features of the claims can be combined with one another in a variety of ways.

[0024] The invention will now be described in more detail using exemplary embodiments. Fig. 1. A block diagram of an example power supply network of a vehicle. Fig. Figure 1 shows a block diagram of an exemplary power supply network 100 of a vehicle (e.g., a passenger car or an automobile). The network 100 includes a (possibly rechargeable) battery 102, which may be located, for example, in the rear of the vehicle. Furthermore, the network 100 includes a plurality of electrical consumers 105, 107, or generators 106, which are connected to the vehicle's battery 102 via a battery connection cable (also called a charging cable) 103. The electrical consumers may, in particular, include a starter 107 for an internal combustion engine of the vehicle. A starter 107 typically requires high power and is therefore preferably connected directly to the battery 102 via the battery connection cable 103. The vehicle also typically includes a generator 106, which is configured to convert the vehicle's kinetic energy into electrical energy.The generator 106 is also usually connected to the battery 102 via the battery connection line 103 in order to store the generated electrical energy in the battery 102.

[0025] Furthermore, other electrical consumers 105 can be connected directly (or possibly indirectly) to the battery 102 via the battery connection cable 103. These consumers 105 can provide various functions in the vehicle.

[0026] The electrical consumers 105, 107 and the generator 106 can be located, for example, in the front area of ​​the vehicle, so that the battery connection cable 103 (e.g. along a cable harness) is routed through the vehicle.

[0027] In the event of an accident, there is a risk of damage to the vehicle's cables (and especially the battery connection cable). Damage to the cables can lead to a short circuit. To eliminate the risk of a short circuit in the event of an accident, the battery charging cable 103 is typically disconnected from the battery 102 after an accident is detected. For this purpose, the vehicle's power supply network 100 typically includes a safety battery terminal (SBK) 101, which is triggered or opened after an accident is detected, thereby interrupting the electrical connection between the battery 102 and the battery charging cable 103. The triggering or opening of the SBK 101 is typically carried out by a control unit 104 of the vehicle, in particular by the airbag control unit.

[0028] In other words, the airbag control unit 104 typically ignites the safety battery terminal (SBK) 101 during a crash to prevent short circuits on the battery charging line 103. The SBK 101 is used because a fuse is usually ineffective due to the high currents on the battery charging line 103 (especially the high starter currents). SBKs 101 can also be used at other locations in the vehicle to interrupt the flow of current on lines of the power supply network 100 in the event of an accident. The procedures and devices described in this document are also applicable to such other SBKs in the vehicle.

[0029] The airbag control unit 104 can be configured to detect a vehicle accident. Specifically, the airbag control unit 104 can determine the impact location, impact speed, etc. This information can be obtained based on sensor data from sensors within the vehicle. Depending on the information gathered regarding the accident, the airbag control unit 104 can then initiate various measures to mitigate the consequences of the accident. For example, airbags and seatbelt pretensioners can be selectively deployed to protect the vehicle occupants from injury.

[0030] Furthermore, the airbag control unit 104 can trigger the activation of the safety brake 101 to disconnect the battery charging line 103 from the battery 102. After activation of the safety brake 101, the electrical consumers 105 and 107 are no longer supplied with electrical energy and therefore typically can no longer provide any functions and / or typically can no longer store data. The airbag control unit 104, on the other hand, usually has an electrical buffer (e.g., a capacitor) to be able to perform certain functions (in particular, the deployment of the airbags and seatbelt tensioners, as well as the activation or opening of the safety brake 101) independently of the power supply.

[0031] On the other hand, other electrical consumers 105 are no longer operational after opening the SBK 101. This can be disadvantageous, as certain functions (e.g., saving data and / or the controlled shutdown of a control unit) can still be beneficial even after a crash has been detected, for example, to save diagnostic data.

[0032] As explained above, the airbag control unit 104 is configured to detect a crash event using sensor data. The control unit 104 may also be configured to monitor the level of its supply voltage. This supply voltage level is typically dependent on the voltage level on the battery terminal 103 and thus serves as an indicator of a short circuit on the battery terminal 103. Conversely, a stable supply voltage level after the detection of a crash event indicates that there is no short circuit on the battery terminal 103.

[0033] The control unit 104 can be connected to the battery 102 via another supply line 108 of the network 100. The supply line 108 can, for example, be independent of the disconnection of the battery connection line 103 by the SBK 101 (as in Fig.(1 shown). In particular, the control unit 104 cannot be connected to the battery 102 via the battery connection line 103. The control unit 104 can then be configured, e.g., using a measuring line 109, to measure the level of the voltage on the battery connection line 103.

[0034] The control unit 104 can thus be configured to monitor not only the sensor data for detecting a crash event, but also the supply voltage of the control unit 104 and / or the voltage on the battery connection cable 103. If a crash event is detected, but it is simultaneously recognized that the supply voltage level and / or the voltage level on the battery connection cable 103 remains stable, then the ejection or opening of the battery compartment 101 can potentially be delayed or even prevented. Thus, the power supply in the vehicle is maintained (at least temporarily) even after a crash event, so that the electrical consumers 105 can continue to perform functions even after the crash event. In particular, data can still be stored.

[0035] In one example, the control unit 104 is configured to delay the release or opening of the SBK 101 (by a predefined time interval of, for example, 500 ms) if it is detected that the supply voltage and / or the voltage on the battery connection cable 103 remains stable after a crash event. During this time, the one or more electrical consumers 105 can still perform functions (such as controlled shutdown and / or data saving).

[0036] When deciding whether to delay (or prevent) the ignition of the SBK 101, the control unit 104 can consider further indicators for or against the presence of a short circuit. In particular, it can consider whether the control unit relies on its own power supply. In other words, the control unit 104 can be configured to detect whether the electrical energy for its operation is supplied by the power supply network 100, or whether the control unit 104 obtains the electrical energy (at least partially) from an intermediate storage device (e.g., a capacitor) within the control unit 104. If the electrical energy continues to be drawn from the power supply network 100, this is a further indication that there has been no short circuit on the battery connection line 103, and thus the ignition or opening of the SBK 101 can be delayed or prevented.By monitoring one or more indicators for or against the presence of a short circuit, it may be possible to avoid unnecessary opening of the SBK 101 and furthermore to eliminate the risk of a short circuit.

[0037] On the other hand, if control unit 104 detects that its supply voltage is dropping and / or the voltage on battery connection line 103 is dropping and / or control unit 104 is dependent on its power supply, these are indications of a short circuit on battery connection line 103. It can therefore be assumed that there is a short circuit to ground on the SBK-protected line 103. In this case, control unit 104 may be configured to immediately output the signal to break or open SBK 101, thus interrupting the connection between battery connection line 103 and battery 102.

[0038] A control unit 104 configured in this way ensures that certain vehicle power supplies 105 can continue to function, at least temporarily, even after a crash. Furthermore, by considering indicators for or against the presence of a short circuit, the risk of short circuits can be eliminated. These indicators (such as the supply voltage level and / or the voltage level on the battery connection cable 103 and / or the use of the vehicle's self-sufficient power supply) can be directly determined at the control unit 104, thus enabling a short reaction time to changing indicators.

[0039] The solution described in this document can be implemented as software on the control unit 104 and is therefore cost-effective.

[0040] The present invention is not limited to the embodiments shown. In particular, it should be noted that the description and the figures are intended only to illustrate the principle of the proposed methods, devices, and systems.

Claims

[1] Control unit (104) for a vehicle, wherein the vehicle comprises a power line (103) which is connected to a battery (102) of the vehicle via a safety battery terminal (101); wherein the control unit (104) is configured, - to detect a vehicle accident; - to determine one or more indications of an impairment of the vehicle's power supply from the battery (102) based on measurement data taken directly at the control unit (104); - to immediately open the safety battery terminal (101) upon detection of the accident if, based on one or more indicators, it is determined that the power line (103) is damaged; and - to delay the opening of the safety battery terminal (101) to disconnect the power line (103) from the battery (102) if, based on one or more indications, it is determined that there is no damage to the power line (103). [2] Control unit (104) according to claim 1, wherein - the control unit (104) is configured to determine a voltage level on the power line (103); and - which include one or more indicators of the voltage level on the power line (103); and / or - the control unit (104) is configured to determine a time course of the voltage on the power line (103); and - which include one or more pieces of evidence that involve a comparison between the determined time course and one or more predefined characteristic stress curves. [3] Control unit (104) according to claim 2, wherein the control unit (104) is configured to delay the opening of the safety battery terminal (101) when the voltage level is equal to or greater than a predefined voltage threshold. [4] Control unit (104) according to any prior claim, wherein - the control unit (104) includes an intermediate storage device to provide temporary energy independence from the battery (102); and - which include one or more pieces of evidence indicating that the energy supply to the control unit (104) is at least partially provided by the intermediate storage device. [5] Control unit (104) according to claim 4, wherein the control unit (104) is configured to delay the opening of the safety battery terminal (101) when a proportion of the energy supply to the control unit (104) that is supplied via the intermediate storage is equal to or less than a predefined proportion threshold. [6] Control unit (104) according to any one of the preceding claims, wherein the control unit (104) is configured, - to delay the opening of the safety battery terminal (101) for a predefined time interval; and - to open the safety battery terminal (101) after the predefined time interval has elapsed. [7] Control unit (104) according to claim 6, wherein the control unit (104) is configured, - to register an accident time at which the accident of the vehicle is detected; - to repeatedly determine one or more indicators regarding the impairment of the vehicle's power supply during the predefined time interval from the time of the accident; and - depending on the one or more repeatedly identified indications, to open the safety battery terminal (101) even before the predefined time interval has elapsed. [8] Control unit (104) according to any prior claim, wherein the control unit (104) comprises an airbag control unit configured to trigger one or more airbags and / or one or more seatbelt pretensioners of the vehicle after detecting an accident of the vehicle. [9] Control unit (104) according to any prior claim, wherein the power line (103) comprises a battery charging line. [10] Method for controlling a safety battery terminal (101) for a vehicle, wherein the vehicle comprises a power line (103) which is connected via the safety battery terminal (101) to a battery (102) of the vehicle; wherein the method comprises, - Detecting a vehicle accident; - Determining one or more indications of an impairment of the power supply by the battery (102) based on measurement data taken directly at the control unit (104); - Opening the safety battery terminal (101) immediately upon detection of the accident if, based on one or more indicators, it is determined that damage to the power line (103) has occurred; and - Delaying the opening of the safety battery terminal (101) to disconnect the power line (103) from the battery (102) if, based on one or more indications, it is determined that there is no damage to the power line (103).

Images