A method and device for charging a low-voltage battery, a vehicle control unit and a vehicle

Abstract

The embodiment of the present application discloses a method for charging a low-voltage battery, which is applied to a vehicle controller of a vehicle, the vehicle comprising a low-voltage battery and a DCDC for charging the low-voltage battery, and comprising: obtaining a first output current of the DCDC in the case that the DCDC charges the low-voltage battery; determining a first working voltage according to a size relationship between the first output current and a first preset current threshold; and sending the first working voltage to the DCDC, so that the DCDC charges the low-voltage battery according to the first working voltage. The embodiment of the present application also simultaneously provides a charging device for a low-voltage battery, a vehicle controller and a vehicle.

Description

Technical Field

[0001] This invention relates to a charging technology for low-voltage batteries in new energy vehicles, and particularly to a charging method, device, vehicle controller, and vehicle for low-voltage batteries. Background Technology

[0002] Currently, with the increasing electrification, intelligence, and connectivity of automobiles, the number of sensors, controllers, and actuators installed in vehicles is also constantly increasing, leading to increased power consumption in low-voltage components. The addition of parking (OFF) mode functionality to new energy vehicles accelerates the depletion of the vehicle's low-voltage battery. In scenarios where the vehicle is parked for extended periods or the driver forgets to turn off low-voltage components (such as headlights) when leaving the vehicle, the low-voltage battery may become depleted, making it difficult to start the vehicle when needed.

[0003] While selecting a large-capacity low-voltage vehicle battery increases the vehicle's low-voltage operating time and delays battery depletion, it also increases production costs and can still lead to battery depletion in certain scenarios. Therefore, it is essential to use the vehicle's electronic control unit to identify battery depletion risks and promptly control the high-voltage system to replenish the low-voltage battery.

[0004] In related technologies, most battery charging solutions use the same Direct Current to Direct Current (DCDC) output voltage as the power converter used when the vehicle is in motion. During the initial charging phase, different charging voltages result in different charging currents; generally, higher charging voltages yield larger charging currents, improving charging efficiency. However, in the later stages of charging, the charging current is relatively small at different voltages, and using higher charging voltages at this point leads to greater low-voltage load consumption. Summary of the Invention

[0005] This invention provides a method, apparatus, vehicle controller, and vehicle for replenishing low-voltage batteries, which can reduce energy consumption during the replenishment of low-voltage batteries in new energy vehicles.

[0006] The technical solution of this invention is implemented as follows:

[0007] This invention provides a method for replenishing a low-voltage battery. This method is applied in a vehicle controller, and the vehicle further includes: a low-voltage battery and a DC-DC converter for replenishing the low-voltage battery, comprising:

[0008] When the DC-DC converter is replenishing the low-voltage battery, the first output current of the DC-DC converter is obtained;

[0009] The first operating voltage is determined based on the relationship between the first output current and the first preset current threshold.

[0010] The first operating voltage is sent to the DC-DC converter so that the DC-DC converter can replenish the low-voltage battery according to the first operating voltage.

[0011] Thus, by acquiring the first output current of the DC-DC converter when it is replenishing the low-voltage battery, the first operating voltage can be determined based on the relationship between the first output current and the first preset current threshold. In this way, the appropriate operating voltage of the DC-DC converter can be determined in real time when replenishing the low-voltage battery. By sending the first operating voltage to the DC-DC converter, the DC-DC converter replenishes the low-voltage battery according to the first operating voltage. In this way, by determining the appropriate operating voltage in real time, the DC-DC converter can operate at an appropriate operating voltage to replenish the low-voltage battery. Furthermore, this allows for real-time adjustment of the DC-DC converter's operating voltage, which helps to reduce energy consumption when the DC-DC converter replenishes the low-voltage battery.

[0012] Furthermore, based on the relationship between the first output current and the first preset current threshold, the first operating voltage is determined, including:

[0013] Obtain the ambient temperature outside the vehicle;

[0014] The target correspondence is determined based on the relationship between the first output current and the first preset current threshold.

[0015] Based on the target correspondence, determine the operating voltage corresponding to the ambient temperature outside the vehicle;

[0016] The first operating voltage is determined by the sum of the operating voltage corresponding to the ambient temperature outside the vehicle and the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery.

[0017] In this way, by acquiring the ambient temperature outside the vehicle and determining the target correspondence, the operating voltage corresponding to the ambient temperature outside the vehicle can be determined. The sum of this voltage and the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery is used as the first operating voltage, so that the DC-DC converter can adjust the operating voltage in real time to reduce the energy consumption during low-voltage battery charging.

[0018] Furthermore, based on the relationship between the first output current and the first preset current threshold, the target correspondence is determined, including:

[0019] If the first output current is greater than the first preset current threshold, the first preset correspondence is determined as the target correspondence.

[0020] If the first output current is less than or equal to the first preset current threshold, the second preset correspondence is determined as the target correspondence.

[0021] In this way, different target correspondences can be determined through different comparison results, thereby determining a more accurate working voltage corresponding to the external ambient temperature of the vehicle, and improving the accuracy of the first working voltage.

[0022] Furthermore, the above methods also include:

[0023] After the vehicle is in the OFF position and the vehicle controller is activated, control the vehicle to apply high voltage;

[0024] After the high voltage is applied to the vehicle, a working command is sent to the DC-DC converter so that the DC-DC converter supplies power to the low-voltage battery and the low-voltage load of the vehicle according to the second working voltage in the working command.

[0025] When the DCDC supplies power to the low-voltage battery and the low-voltage load respectively according to the second working voltage in the working instruction, the second output current of the DCDC is obtained within the first preset time period.

[0026] Based on the ratio of the duration of the second output current exceeding the second preset current threshold to the first preset time period, it is determined whether the DC-DC converter should replenish the low-voltage battery.

[0027] Thus, by sending working instructions to the DC-DC converter to control it to supply power to the low-voltage battery and low-voltage load, the second output current within a first preset time period is obtained during the power supply, and the duration of the current in the second output current that is greater than the second preset current threshold is calculated, and the proportion of this duration to the first preset time period is calculated. Based on this proportion, it is determined whether the DC-DC converter should replenish the low-voltage battery. This can accurately determine whether to replenish the low-voltage battery.

[0028] Furthermore, based on the ratio of the duration of the current exceeding the second preset current threshold in the second output current to the first preset time period, it is determined whether the DC-DC converter should replenish the low-voltage battery, including:

[0029] If the duration of the current exceeding the second preset current threshold in the second output current is greater than the proportion of the first preset time period, it is determined that the DC-DC converter is replenishing the low-voltage battery.

[0030] If the duration of the second output current that is less than or equal to the second preset current threshold is greater than the ratio of the first preset time period to a preset ratio, it is determined that the DC-DC converter is prohibited from charging the low-voltage battery.

[0031] Thus, by comparing the proportion of the duration of the second output current exceeding the second preset current threshold to the first preset time period with the preset proportion, it is possible to determine whether the DC-DC converter is replenishing the low-voltage battery, making the determination of whether the DC-DC converter is replenishing the low-voltage battery more accurate.

[0032] Furthermore, the second preset current threshold is equal to the sum of the third preset current threshold and the fourth preset current threshold;

[0033] The third preset current threshold is the current supplied to the low-voltage load when the DCDC is charging the low-voltage battery while the vehicle is in the OFF position; the fourth preset current threshold is the current supplied to the low-voltage battery using a set voltage when the set remaining charge is turned on.

[0034] Thus, after obtaining the third and fourth preset current thresholds through testing, the two are summed, and the summed value is stored locally as the second preset current threshold. This is used to determine whether the DC-DC converter is replenishing the low-voltage battery, which helps to accurately determine whether the DC-DC converter is replenishing the low-voltage battery.

[0035] Furthermore, the fourth preset current threshold is related to the ambient temperature outside the vehicle.

[0036] In this way, a fourth preset current threshold corresponding to the ambient temperature can be determined, which is helpful in determining a more accurate second preset current threshold and improving the accuracy of whether the DC-DC converter is charging the low-voltage battery.

[0037] This invention also provides a low-voltage battery charging device, which is installed in the vehicle controller of a vehicle. The vehicle further includes: a low-voltage battery and a DC-DC converter for charging the low-voltage battery, comprising:

[0038] The acquisition module is used to acquire the first output current of the DC-DC converter when the DC-DC converter is replenishing the low-voltage battery;

[0039] The determining module is used to determine the first operating voltage based on the relationship between the first output current and the first preset current threshold.

[0040] The charging module is used to send the first operating voltage to the DC-DC converter so that the DC-DC converter can charge the low-voltage battery according to the first operating voltage.

[0041] This invention also provides a vehicle controller, including: a processor and a storage medium storing executable instructions of the processor. The storage medium performs operations via a communication bus in dependence of the processor. When the instructions are executed by the processor, the low-voltage battery charging method described in one or more of the above embodiments is executed.

[0042] This invention also provides a vehicle, including a vehicle controller as described in one or more of the above embodiments.

[0043] This invention also provides a computer storage medium, characterized in that it stores executable instructions, which, when executed by a processor, enable the processor to perform a low-voltage battery charging method as described in one or more of the above embodiments.

[0044] This invention also provides a computer program product, including a computer program or instructions, characterized in that, when the computer program or instructions are executed by a processor, they implement the steps of the low-voltage battery charging method described in one or more of the above embodiments.

[0045] The beneficial effects of this invention are:

[0046] (1) By obtaining the first output current of the DCDC when the DCDC is replenishing the low-voltage battery, the first working voltage can be determined according to the relationship between the first output current and the first preset current threshold. In this way, the appropriate working voltage of the DCDC can be determined in real time when replenishing the low-voltage battery.

[0047] (2) By sending the first working voltage to the DCDC, the DCDC can replenish the low-voltage battery according to the first working voltage. In this way, by determining the appropriate working voltage in real time, the DCDC can operate at the appropriate working voltage to replenish the low-voltage battery. Furthermore, the working voltage of the DCDC can be adjusted in real time, which helps to reduce the energy consumption of the DCDC in replenishing the low-voltage battery. Attached Figure Description

[0048] Figure 1 A schematic flowchart illustrating an optional low-voltage battery charging method provided in an embodiment of the present invention;

[0049] Figure 2 A schematic diagram illustrating an example of an optional DC-DC output current provided in an embodiment of the present invention;

[0050] Figure 3 A schematic diagram illustrating an example of an optional intelligent power replenishment system provided in an embodiment of the present invention;

[0051] Figure 4 A flowchart illustrating an example of an optional low-voltage battery charging method provided in this embodiment of the invention;

[0052] Figure 5 A flowchart illustrating an example of an optional intelligent power replenishment demand determination method provided in this embodiment of the invention;

[0053] Figure 6 A schematic diagram of an optional low-voltage battery charging device provided in an embodiment of the present invention;

[0054] Figure 7 A schematic diagram of an optional vehicle controller provided in an embodiment of the present invention;

[0055] Figure 8 This is a schematic diagram of an optional vehicle structure provided for an embodiment of the present invention. Detailed Implementation

[0056] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0057] In view of the high energy consumption problem in low-voltage battery charging in related technologies, this invention provides a method for charging a low-voltage battery. This method is applied in a vehicle controller, and the vehicle further includes a low-voltage battery and a DC-DC converter for charging the low-voltage battery. Figure 1 A schematic flowchart of an optional low-voltage battery charging method provided in an embodiment of the present invention is shown below. Figure 1 As shown, the method may include:

[0058] S101: Obtain the first output current of the DCDC when the DCDC is replenishing the low-voltage battery;

[0059] To reduce the high energy consumption problem in low-voltage battery charging, in this embodiment of the invention, when the DC-DC converter is charging the low-voltage battery, the vehicle controller acquires the output current of the DC-DC converter, which is denoted as the first output current. Here, the DC-DC converter charging the low-voltage battery can be the vehicle's power battery charging the low-voltage battery through the DC-DC converter, or it can be an external charging pile charging the low-voltage battery through the DC-DC converter, or it can be the vehicle's engine charging the low-voltage battery through the DC-DC converter. This embodiment of the invention does not specifically limit the specific charging methods.

[0060] In addition, the operating voltage of the DC-DC converter when replenishing the low-voltage battery can be recorded as the second operating voltage. In order to adjust the operating voltage of the DC-DC converter, in S101, the vehicle controller obtains the first output current of the DC-DC converter. The first output current is the sum of the current on the low-voltage battery and the current on the low-voltage load. The low-voltage load refers to components and controllers that need to be powered, other than the low-voltage battery.

[0061] S102: Determine the first operating voltage based on the relationship between the first output current and the first preset current threshold.

[0062] In step S101, when the DC-DC converter is charging the low-voltage battery, the vehicle controller obtains the first output current of the DC-DC converter. In step S102, the first operating voltage is determined based on the relationship between the first output current and the first preset current threshold. Here, the vehicle controller compares the first output current with the first preset current threshold and determines the first operating voltage based on the comparison result.

[0063] In other words, the relationship between the first output current and the first preset current threshold determines the different ways to determine the first operating voltage. For example, different correspondences can be determined for the magnitude relationship, and then the first operating voltage can be determined based on the determined correspondence.

[0064] S103: Send the first operating voltage to the DCDC so that the DCDC can replenish the low-voltage battery according to the first operating voltage.

[0065] After the vehicle controller determines the first operating voltage in S102, in S103, the vehicle controller sends the first operating voltage to the DC-DC converter, so that the DC-DC converter can replenish the low-voltage battery according to the first operating voltage.

[0066] In other words, during the process of DC-DC charging the low-voltage battery, the output current of DC-DC to the low-voltage battery is acquired in real time and compared with the first preset current threshold to determine the operating voltage of DC-DC. In this way, the output voltage of DC-DC can be adjusted in real time, which helps to reduce energy consumption during battery charging.

[0067] In order to determine the first operating voltage, in one alternative embodiment, S102 may include:

[0068] Obtain the ambient temperature outside the vehicle;

[0069] The target correspondence is determined based on the relationship between the first output current and the first preset current threshold.

[0070] Based on the target correspondence, determine the operating voltage corresponding to the ambient temperature outside the vehicle;

[0071] The first operating voltage is determined by the sum of the operating voltage corresponding to the ambient temperature outside the vehicle and the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery.

[0072] Understandably, the vehicle controller needs to acquire the ambient temperature outside the vehicle. This can be achieved by detecting the ambient temperature outside the vehicle through sensors or by other devices. This embodiment of the invention does not specifically limit this.

[0073] After the vehicle controller obtains the ambient temperature outside the vehicle, it determines the target correspondence based on the relationship between the first output current and the first preset current threshold. Then, based on the target correspondence, it determines the operating voltage corresponding to the ambient temperature outside the vehicle. The sum of the operating voltage corresponding to the ambient temperature outside the vehicle and the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery is taken as the first operating voltage.

[0074] In other words, the target correspondence can be determined based on the relationship between the first output current and the first preset current threshold. This target correspondence stores the correspondence between ambient temperature and operating voltage. Based on this, the operating voltage corresponding to the ambient temperature outside the vehicle can be determined. Then, this voltage is summed with the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery to obtain the first operating voltage. Here, the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery can be a fixed value stored in the vehicle controller, or it can be a value obtained in real time. Here, this embodiment of the invention does not specifically limit this.

[0075] In this way, by acquiring the ambient temperature outside the vehicle and determining the target correspondence, the operating voltage corresponding to the ambient temperature outside the vehicle can be determined. The sum of this voltage and the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery is used as the first operating voltage, so that the DC-DC converter can adjust the operating voltage in real time to reduce the energy consumption during low-voltage battery charging.

[0076] To determine the target correspondence, in one optional embodiment, the target correspondence is determined based on the magnitude relationship between the first output current and the first preset current threshold, which may include:

[0077] If the first output current is greater than the first preset current threshold, the first preset correspondence is determined as the target correspondence.

[0078] If the first output current is less than or equal to the first preset current threshold, the second preset correspondence is determined as the target correspondence.

[0079] Understandably, by comparing the first output current with the first preset current threshold, if the comparison result is that the first output current is greater than the first preset current threshold, the first preset correspondence is used as the target correspondence; if the comparison result is that the first output current is less than or equal to the first preset current threshold, the second preset correspondence is used as the target correspondence. The first and second preset correspondences are correspondences that are pre-stored locally.

[0080] For example, the vehicle controller receives the first output current of the DC-DC converter and the ambient temperature signal outside the vehicle sent by the body controller, and calculates the first operating voltage U2 of the DC-DC converter when the power supply function is turned on: U2 = U3 + ΔU.

[0081] Wherein, ΔU is the line voltage drop from the output terminal of the DC-DC converter to the low-voltage battery terminal, which can be determined by actual vehicle measurement and testing based on the actual vehicle wiring harness and low-voltage load configuration; U3 is the target charging voltage of the low-voltage battery. When the first output current of the DC-DC converter is greater than the DC-DC output current threshold I2 (equivalent to the aforementioned first preset current threshold), U3 is determined by referring to Table 1, the target charging voltage of the low-voltage battery under supplementary electrical conditions, based on the ambient temperature. When the first output current of the DC-DC converter is less than or equal to the DC-DC output current threshold I2, U3 is determined by referring to Table 2, the target charging voltage of the low-voltage battery under supplementary electrical conditions, based on the ambient temperature.

[0082] The DC-DC output current threshold I2 is the low-voltage battery current when the battery is nearly fully charged (e.g., 80%), determined through testing based on the actual low-voltage battery installed. Examples of target charging voltage meters 1 and 2 for low-voltage batteries under charging conditions are shown below:

[0083] Table 1

[0084]

[0085] The data division dimensions and filling data in Table 1 are for ease of description only. The actual application data dimensions and data are determined by testing the low-voltage batteries installed under different ambient temperatures. The method for determining U3 in Table 1 is to charge the low-voltage batteries with different voltages under the same ambient temperature, and select the voltage with the largest charging current as the target charging voltage of the low-voltage batteries under that ambient temperature. The target charging voltage of the low-voltage batteries under different ambient temperatures is determined by analogy.

[0086] Table 2

[0087]

[0088] The data division dimensions and filling data in Table 2 are for ease of description only. The actual application data dimensions and data are determined by testing the actual low-voltage batteries under different ambient temperatures. The method for determining U3 in Table 2 is to charge the low-voltage batteries with different voltages under the same ambient temperature, and select the voltage with the highest charge after charging within the same time period as the target charging voltage of the low-voltage batteries under that ambient temperature. The target charging voltage of the low-voltage batteries under that ambient temperature is determined by analogy.

[0089] Finally, the DC-DC converter receives and outputs low-voltage DC power according to the target operating voltage U2 of the vehicle controller's DC-DC converter to replenish the low-voltage battery.

[0090] In this way, different target correspondences can be determined through different comparison results, thereby determining a more accurate working voltage corresponding to the external ambient temperature of the vehicle, and improving the accuracy of the first working voltage.

[0091] In order to accurately determine whether the DC-DC converter is replenishing the low-voltage battery, in an optional embodiment, the above method may further include:

[0092] After the vehicle is in the OFF position and the vehicle controller is activated, control the vehicle to apply high voltage;

[0093] After the high voltage is completed on the vehicle, a working command is sent to the DC-DC converter so that the DC-DC converter can supply power to the low-voltage battery and the low-voltage load of the vehicle according to the second working voltage in the working command.

[0094] When the DC-DC supplies power to the low-voltage battery and the low-voltage load of the vehicle according to the second operating voltage in the working instruction, the second output current of the DC-DC during the first preset time period is obtained.

[0095] Based on the ratio of the duration of the second output current exceeding the second preset current threshold to the first preset time period, it is determined whether the DC-DC converter should replenish the low-voltage battery.

[0096] Understandably, when the vehicle's power is off, the on-board electronic control unit (OECU) supporting timed wake-up (e.g., Body Domain Controller, hereinafter referred to as BDC for convenience) periodically wakes up. Every so often, T1 automatically wakes up once. This wake-up is achieved through network management, waking up relevant vehicle network segments (the wake-up objects include at least the Vehicle Control Unit (VCU), Battery Management System (BMS), DC-DC converter, Head Unit (HU), and Onboard Charger (OBC)). It also detects and sends the external ambient temperature to the vehicle controller.

[0097] After being woken up, the vehicle controller sends a high-voltage command to the BMS to control the high-voltage connection of the entire vehicle. After the high-voltage connection is completed, the vehicle controller sends a command to the DC-DC converter to instruct it to operate, and simultaneously sends the target operating voltage U1 to the DC-DC converter, which is denoted as the second operating voltage.

[0098] After receiving the operating command and the second operating voltage U1 from the vehicle controller, the DCDC operates at the target operating voltage U1 and outputs current to the low-voltage battery and low-voltage load. The DCDC detects the output current of the DCDC in real time within the first preset time period, records it as the second output current, and sends it to the vehicle controller.

[0099] The vehicle controller calculates the duration of the current in the second output current that is greater than the second preset current threshold, and calculates the proportion of this duration to the first preset time period. Based on this proportion, it determines whether the DC-DC converter should replenish the low-voltage battery.

[0100] Thus, by sending working instructions to the DC-DC converter to control it to supply power to the low-voltage battery and low-voltage load, the second output current within a first preset time period is obtained during the power supply, and the duration of the current in the second output current that is greater than the second preset current threshold is calculated, and the proportion of this duration to the first preset time period is calculated. Based on this proportion, it is determined whether the DC-DC converter should replenish the low-voltage battery. This can accurately determine whether to replenish the low-voltage battery.

[0101] To more accurately determine whether the DC-DC converter is replenishing the low-voltage battery, in one optional embodiment, the determination of whether the DC-DC converter is replenishing the low-voltage battery is based on the ratio of the duration of the current in the second output current that is greater than a second preset current threshold to a first preset time period, including:

[0102] If the duration of the current exceeding the second preset current threshold in the second output current is greater than the ratio of the duration of the first preset time period to the preset ratio, it is determined that the DC-DC converter is replenishing the low-voltage battery.

[0103] If the duration of the second output current that is less than or equal to the second preset current threshold is greater than the proportion of the first preset time period, it is determined that the DC-DC converter is prohibited from charging the low-voltage battery.

[0104] Understandably, the calculation determines the proportion of the duration of current exceeding the second preset current threshold in the second output current relative to the first preset time period. If this proportion is greater than the preset proportion, it indicates that the duration of current exceeding the second preset current threshold is relatively large within the first preset time period, thus determining that the DC-DC converter is supplying power to the low-voltage battery. If this proportion is less than or equal to the preset proportion, it indicates that the duration of current exceeding the second preset current threshold is relatively small within the first preset time period, thus determining that the DC-DC converter is prohibited from supplying power to the low-voltage battery.

[0105] The aforementioned preset ratio can be 70%.

[0106] Thus, by comparing the proportion of the duration of the second output current exceeding the second preset current threshold to the first preset time period with the preset proportion, it is possible to determine whether the DC-DC converter is replenishing the low-voltage battery, making the determination of whether the DC-DC converter is replenishing the low-voltage battery more accurate.

[0107] Regarding the aforementioned second preset current threshold, in one optional embodiment, the second preset current threshold is equal to the sum of the third preset current threshold and the fourth preset current threshold;

[0108] Understandably, the second preset current threshold is the sum of the third preset current threshold and the fourth current threshold. The third preset current threshold is the current supplied to the low-voltage load when the vehicle is in the OFF position and the DC-DC converter is charging the low-voltage battery. The fourth preset current threshold is the current used to charge the low-voltage battery with a set voltage when the remaining charge is set to be activated.

[0109] In other words, after obtaining the third and fourth preset current thresholds through testing, the two are summed, and the summed value is stored locally as the second preset current threshold. This is used to determine whether the DC-DC converter is replenishing the low-voltage battery, which helps to accurately determine whether the DC-DC converter is replenishing the low-voltage battery.

[0110] Regarding the aforementioned fourth preset current threshold, in one optional embodiment, the fourth preset current threshold is related to the ambient temperature outside the vehicle.

[0111] Understandably, in the process of determining the fourth preset current threshold using testing, the fourth preset current threshold determined by different ambient temperatures will be different, which indicates that the fourth preset current threshold is related to the ambient temperature outside the vehicle.

[0112] In this way, the correspondence between the fourth preset current threshold and the ambient temperature can be stored locally, and then used to determine the fourth preset current threshold under different ambient temperatures.

[0113] In this way, a fourth preset current threshold corresponding to the ambient temperature can be determined, which is helpful in determining a more accurate second preset current threshold and improving the accuracy of whether the DC-DC converter is charging the low-voltage battery.

[0114] For example, when the vehicle is in the OFF position and the vehicle controller is activated, the vehicle controller sends a high-voltage command to the BMS to control the high-voltage connection of the entire vehicle. After the high-voltage connection is complete, the vehicle controller sends a command to the DC-DC converter to instruct it to operate, and simultaneously sends the target operating voltage U1 (equivalent to the second operating voltage mentioned above) to the DC-DC converter. Upon receiving the operating command and the target operating voltage U1 from the vehicle controller, the DC-DC converter operates at the target operating voltage U1, outputting current to power the battery and low-voltage loads. The DC-DC converter monitors the output current in real time and sends it back to the vehicle controller.

[0115] Within a time period T3 (equivalent to the first preset time period mentioned above) after the DCDC working command is sent, the vehicle controller receives the DCDC output current and calculates the time T4 during which the DCDC output current exceeds the DCDC output current threshold I1 (equivalent to the second preset current threshold mentioned above). If T4 / T3 is greater than 70%, the vehicle controller determines that there is a need for intelligent power replenishment; otherwise, the vehicle controller determines that there is no need for intelligent power replenishment.

[0116] Figure 2 A schematic diagram illustrating an example of an optional DC-DC output current provided by an embodiment of the present invention, as shown below. Figure 2 As shown, the output current change of the DC-DC converter within T3 is as follows. It can be seen that the time period with a value greater than I1 includes L2 and L4. Therefore, T4 can be calculated as follows: T4 = L2 + L4.

[0117] For example, two DC-DC output current thresholds I1 and I2 can be set (where I1 > I2).

[0118] The DC-DC output current threshold I1 = I11 + I12. Where I11 is the sum of the currents at the low-voltage load terminals (excluding the battery) when charging in the OFF position, determined through testing based on actual vehicle models. I12 is the low-voltage battery terminal current when charging the battery with a constant voltage at the set remaining charge level (e.g., if the setting is that charging is needed when the low-voltage battery has 50% remaining charge, then the current is calculated by testing at a constant voltage U1 and temperature W1 when charging a battery with 50% remaining charge).

[0119] The charging current of the low-voltage battery is affected by factors such as charging voltage, battery charge, and temperature. Therefore, based on the ambient temperature detected by the vehicle controller, the DC-DC output current threshold I1 when the low-voltage battery needs recharging is obtained by looking up a table. See Table 3 below:

[0120] Table 3

[0121]

[0122] The data division dimensions and filling data in Table 3 are for ease of description only. The actual application data dimensions and data are determined based on the actual battery being installed under different ambient temperatures.

[0123] The following examples illustrate the method for replenishing the low-voltage battery described in one or more of the above embodiments.

[0124] Figure 3 A schematic diagram illustrating an example of an optional intelligent power replenishment system provided in an embodiment of the present invention, such as... Figure 3 As shown, the intelligent charging system 300 may include: a low-voltage battery 31, a DC-DC converter 32, a power battery pack 33, an OBC 34, a BMS 35, a BDC 36, a HU 37, a VCU 38, an engine controller 39, a motor controller 40, a motor 41, and an engine 42. The OBC 34 has high-voltage, low-voltage, and communication connections with the charging pile 301; the motor 41 is mechanically connected to the engine; the power battery pack 33 has high-voltage connections with the DC-DC converter 32, the motor 40, and the OBC 34; the power battery pack 33 has a low-voltage connection with the BMS 35; the engine 42 has a low-voltage connection with the engine controller 40; the DC-DC converter 32 has a low-voltage connection with the low-voltage battery 31; the low-voltage battery 31 has a low-voltage connection with the BDC 36; and the DC-DC converter 32, BMS 35, motor controller 40, engine controller 39, VCU 38, HU 37, and BDC 36 have communication connections.

[0125] Based on the above Figure 3 The intelligent power replenishment system 300 Figure 4 A flowchart illustrating an example of an optional low-voltage battery charging method provided in this embodiment of the invention is shown below. Figure 4 As shown, the method for replenishing the low-voltage battery may include:

[0126] S401: The body controller is periodically woken up. It wakes up the vehicle network through network management and detects and sends the ambient temperature to the vehicle controller.

[0127] Here, when the vehicle is powered off and the power supply is in the OFF position, the on-board electronic control unit (e.g., BDC, hereinafter referred to as BDC) that supports timed wake-up function will periodically wake up the vehicle. T1 will self-wake up once every certain period of time, and the wake-up will be performed via network management to wake up the relevant network segments of the entire vehicle (the wake-up objects include at least VCU, BMS, DC-DC, HU, and OBC). It will also detect and send the external ambient temperature to the vehicle controller.

[0128] Among them, time T1 is the time for the body controller to periodically wake up and detect the low-voltage battery charging needs. It can be evaluated based on the actual battery capacity used, and is generally defined between 0.5 and 3 hours.

[0129] S402: After BMS wakes up, it detects and sends the AC gun connection status to the vehicle controller. After BMS wakes up, it detects and sends the power battery SOC to the vehicle controller. After HU wakes up, it calculates and sends the vehicle power-off duration to the vehicle controller.

[0130] After the BMS is woken up, it sends the AC charging gun connection status and the power battery SOC information to the vehicle controller. After the HU is woken up, it calculates and sends the vehicle power-off duration to the vehicle controller in real time.

[0131] Here, the method for calculating the vehicle power-off duration is as follows: At the moment the vehicle is powered off, the HU stores and remembers the time point t0 of that moment. When the vehicle power is in the OFF position, and the HU is woken up, the difference between the current time t1 and the stored power-off time point t0 is used to obtain the vehicle power-off duration.

[0132] S403: The vehicle controller determines whether the AC gun is connected; if yes, execute S404; if no, execute S4031.

[0133] The vehicle controller, upon waking up, receives and determines the AC charging gun connection status. For example, if the BMS indicates that the AC charging gun is connected but not charging, it enters the connected charging mode for power replenishment and executes S404; otherwise, it enters the non-connected charging mode for power replenishment and executes S4031.

[0134] The charging pile-connected power supply mode refers to using the power from the charging pile to replenish the battery when the high voltage of the power battery is cut off, while the non-charging pile-connected power supply mode refers to using the power battery to replenish the battery.

[0135] S404: Does the vehicle controller determine if the current vehicle status condition 1 is met? If yes, execute S405; if no, execute S4025.

[0136] Specifically, in the battery charging mode, the vehicle controller determines whether the current vehicle status condition 1 is met. For example, if the vehicle status condition 1 is met, then S405 is executed to determine whether the battery has a smart charging requirement. Otherwise, S4025 is executed.

[0137] Among them, the vehicle status condition 1 includes whether the current vehicle power supply is in the OFF position, whether the vehicle power-off time exceeds the time period T2, whether there is a fault in the vehicle high voltage system, and whether the power battery SOC is greater than the power battery remaining power threshold C1.

[0138] Here, time period T2 is the time to avoid the driver having an active need to reduce the high voltage during the power-off period. Charging should not be allowed during this time period, and it can be evaluated based on actual usage, generally defined as between 15 and 30 minutes. Threshold C1 is the power battery's self-protection SOC value, generally taken as 20%.

[0139] S405: The vehicle controller determines whether the low-voltage battery needs intelligent charging; if yes, proceed to S406; if no, proceed to S4025.

[0140] Figure 5 A flowchart illustrating an example of an optional intelligent power replenishment demand determination method provided in this embodiment of the invention is shown below. Figure 5 As shown, the method may include:

[0141] S501: The vehicle controller sends a high-voltage command to the BMS to control the vehicle to connect to high voltage. After the vehicle is connected to high voltage, the vehicle controller sends a command to the DC-DC to instruct the DC-DC to output current.

[0142] Specifically, the vehicle controller sends a command to the DC-DC converter to instruct it to output current, and simultaneously sends the target operating voltage U1. U1 is a fixed value, representing the target operating voltage sent by the vehicle controller to the DC-DC converter under normal driving conditions.

[0143] S502: The DC-DC converter detects and sends the DC-DC output current to the vehicle controller in real time.

[0144] After receiving the operating command and target operating voltage from the vehicle controller, the DC-DC converter operates at the target operating voltage, outputting current to power the battery and low-voltage loads. The DC-DC converter monitors the real-time output current and sends it back to the vehicle controller.

[0145] S503: The vehicle controller receives the DC-DC output current and ambient temperature to calculate whether the low-voltage battery needs intelligent charging.

[0146] Within a time period T3 after the DCDC operating command is sent, the vehicle controller receives the DCDC output current and determines and calculates the time T4 during which the DCDC output current exceeds the DCDC output current threshold I1. If T4 / T3 is greater than 70%, the vehicle controller determines that there is a need for intelligent charging and executes S406; the time period T3 is generally 60-90 seconds. Otherwise, the vehicle controller determines that there is no need for intelligent charging and executes S4025. The specific calculation method for intelligent charging needs is the same as the charging method for low-voltage batteries described above, and will not be repeated here.

[0147] S406: The vehicle controller sends a charging-only power replenishment request to the BMS;

[0148] In the charging and replenishment mode, when the vehicle controller determines that there is a need for intelligent replenishment, it sends a charging-only replenishment request to the BMS as a request.

[0149] S407: After the BMS receives a charging-only power replenishment request, it sends a work request command to the OBC, and after the OBC enters the working state, it sends a charging-only power replenishment low voltage request to the vehicle controller.

[0150] In other words, after the BMS receives a charging-only power replenishment request, it sends a work request command to the OBC, and after the OBC enters the working state, it sends a charging-only power replenishment low voltage request to the vehicle controller.

[0151] S408: The vehicle controller receives and determines whether the high-voltage charging request sent by the BMS is valid. If yes, execute S4081; if no, execute S4082.

[0152] S4081: When the vehicle controller receives a high-voltage charging request from the BMS, it sends a high-voltage reduction command to the BMS to control the vehicle to reduce the high voltage.

[0153] Specifically, when the vehicle controller receives a request from the BMS to reduce the high voltage for charging only, the vehicle controller sends a high voltage reduction command to the BMS to control the power battery to reduce the high voltage.

[0154] S4082: Does the vehicle controller determine whether the BMS's high-voltage charging request (only replenishing power) has exceeded time T6? If yes, execute S415; if no, return to execute S408.

[0155] Specifically, when the vehicle controller receives a high-voltage charging request from the BMS that only replenishes power but there is no request for a certain period of time T6, it will switch to S4015. The time T6 is the time for the BMS to request the OBC to work and for the OBC to enter the working state and make corresponding feedback to the BMS. It is evaluated according to the actual usage and is generally defined as 20 to 60 seconds.

[0156] S409: The BMS sends the external charging current and voltage requirements to the OBC, and the OBC converts the charging pile's electrical energy into DC power.

[0157] The BMS sends the required current and voltage for external charging to the on-board charger (OBC), and the OBC converts the charging pile's electrical energy into DC power according to the BMS's request.

[0158] S410: The vehicle controller enters intelligent power replenishment, calculates the power replenishment duration, and calculates the target operating voltage of the DC-DC converter in real time and sends it to the DC-DC converter.

[0159] When the battery is at high voltage and the OBC is in working output mode, the vehicle controller enters the intelligent charging function and begins timing the charging duration. Simultaneously, the vehicle controller calculates the target operating voltage U2 of the DC-DC converter based on factors such as the DC-DC current and ambient temperature, and sends this calculation to the DC-DC converter. The calculation method for the target operating voltage U2 is the same as the low-voltage battery charging method described above, and will not be repeated here.

[0160] S411: The DC-DC receiver receives the target operating voltage of the vehicle controller's DC-DC, and the DC-DC converts the high-voltage DC to low-voltage DC to replenish the low-voltage battery.

[0161] S412: Does the vehicle controller determine if the power replenishment exit condition 1 is met? If yes, execute S4121; if no, execute S410.

[0162] S4121: The vehicle controller sends no charging / replenishment request to the BMS;

[0163] In other words, if condition 1 for power replenishment exit is met, the vehicle controller will send a power replenishment request to the BMS that is not requested. Otherwise, it will switch back to S410 and continue to maintain power replenishment.

[0164] Among them, the charging exit condition 1 refers to: the vehicle power supply is in the local ON position, the vehicle high voltage system has a fault, the DC-DC converter does not work after the vehicle enters the charging function, and the DC-DC converter starts working for more than a certain time T5 after the vehicle enters the charging function (the time T5 can be set to 0.5 to 2 hours).

[0165] S413: After the BMS receives a "no request" for charging only, it sends a command to the OBC to control the OBC to stop working.

[0166] S414: The vehicle controller exits the intelligent power replenishment function, the vehicle is de-energized, and S425 is executed.

[0167] S415: The vehicle controller sends a charging request to the BMS, but no request is received.

[0168] In the charging and replenishment mode, after the vehicle controller sends a charging-only replenishment request to the BMS, the BMS fails to request the OBC to work. The BMS does not send a charging-only replenishment high voltage request to the vehicle controller. If the vehicle controller receives the charging-only replenishment high voltage request sent by the BMS as no request for a certain period of time T6, the vehicle controller will send a charging-only replenishment request to the BMS as no request.

[0169] S416: After the BMS receives a "no request" for charging only and then sends a command to the OBC to stop the OBC from working;

[0170] After receiving a "no request" message from the vehicle controller indicating that the charging request is for supplementary power only, the BMS sends a command to the OBC to stop operating. Then, the vehicle controller performs a power supplementation condition check in the non-charging-connected power supply mode.

[0171] S417: Does the vehicle controller determine whether vehicle status condition 2 is met? If yes, execute S4171; if no, execute S414.

[0172] S4171: Does the vehicle controller determine if there is a smart charging request for the low-voltage battery? If yes, proceed to S410; if no, proceed to S425.

[0173] If the vehicle status condition 2 is satisfied, the vehicle controller determines whether the low-voltage battery requires intelligent charging. Otherwise, it proceeds to step S414, and the vehicle controller exits the intelligent charging function. (The method for determining the intelligent charging requirement is the same as the method for charging the low-voltage battery described above, and will not be repeated here.)

[0174] Among them, vehicle status condition 2 includes whether the current vehicle power supply is in the OFF position, whether the vehicle power-off time exceeds the time period T2, whether there is a fault in the vehicle high voltage system, and whether the power battery SOC is greater than the power battery remaining power threshold C1.

[0175] S418: When the vehicle system is woken up, it detects the driver's electric start setting (allow / disallow) in real time and sends it to the vehicle controller.

[0176] The vehicle's infotainment system provides a setting switch on the user interface to indicate whether starting the engine to generate electricity is allowed during the charging process (see the charging start engine setting switch options: Allow / Disallow). After the driver selects the corresponding setting option (e.g., Allow / Disallow), the vehicle's infotainment system will store the charging start engine setting and send the setting information to the vehicle controller in real time.

[0177] S419: After the vehicle is powered off, the vehicle's infotainment system should store the engine start-up settings information before going into sleep mode.

[0178] S420: The vehicle controller enters intelligent power replenishment, calculates the power replenishment duration, and calculates the target operating voltage of the DC-DC converter and sends it to the DC-DC converter.

[0179] In non-pile-connected power supply mode, when the vehicle controller detects a need for intelligent power supply, it enters the intelligent power supply function and begins timing the power supply duration. Simultaneously, the vehicle controller calculates the target operating voltage U2 of the DC-DC converter based on factors such as the DC-DC current and ambient temperature, and sends this calculation to the DC-DC converter. The calculation method for the target operating voltage U2 is similar to the low-voltage battery power supply method described above, and will not be repeated here.

[0180] S421: The DC-DC receiver receives the target operating voltage of the vehicle controller's DC-DC converter. The DC-DC converter converts high-voltage DC power into low-voltage DC power to replenish the low-voltage battery.

[0181] S422: The vehicle controller determines whether the charging start-up setting sent by the vehicle unit is allowed, and whether the power battery SOC is less than the limit C2. If both are yes, execute S4221; otherwise, execute S424.

[0182] Among them, after the intelligent charging function is successfully activated, during the process of the DC-DC converter charging the battery, the vehicle controller receives and judges the charging engine setting signal and the remaining power battery power sent by the vehicle machine.

[0183] S4221: The vehicle controller remotely starts the engine to generate electricity and charge the power battery;

[0184] For example, if the vehicle's infotainment system sends a signal to enable engine start-up, and the remaining battery charge is less than the limit C2 for the remaining battery charge of the engine start-up system, and the current remaining fuel is greater than the limit F1, then the vehicle controller will remotely start the engine to drive the motor to generate electricity and charge the battery.

[0185] Among them, the remaining power limit C2 of the power battery of the electric start engine can be set to 23%, and the remaining fuel limit F1 of the electric start engine can be set to 9L. There are no restrictions on the specific values ​​for the function execution.

[0186] S423: Does the vehicle controller determine if the SOC of the power battery exceeds the limit C3? If yes, execute S4231; if no, execute S424.

[0187] During the intelligent power replenishment process, after the engine is started to generate electricity to charge the power battery, the vehicle controller receives and judges the remaining power battery capacity.

[0188] S4231: The vehicle controller controls the remote engine shutdown, causing the engine to stop.

[0189] When the remaining charge of the power battery exceeds the limit C3 for disabling remote engine start, the vehicle controller will disabling remote engine start and shutting down the engine.

[0190] Among them, the remaining power limit C3 for disabling the auxiliary power start engine can be set to 28%, and there is no limit to the specific value of the function execution.

[0191] S424: Does the vehicle controller determine if the power replenishment exit condition 2 is met? If yes, execute S4241; if no, execute S420.

[0192] S4241: The vehicle controller controls the remote engine start to be deactivated, causing the engine to stop. The vehicle controller also controls the power supply function to be deactivated, and the vehicle is de-energized.

[0193] If the charging exit condition 2 is met, the vehicle controller ensures that the remote engine start state is exited (e.g., after starting the engine based on the charging function, if the remaining battery charge is not greater than the battery charge limit C3 for exiting the remote engine start state, causing the engine to remain running, the vehicle controller will exit the remote engine start state and stop the engine). The vehicle controller will then exit the intelligent charging function and send a high-voltage reduction command to the battery management system (BMS) to control the vehicle to reduce high voltage. If the charging exit condition 2 is not met, the process will return to continue executing S420.

[0194] Among them, the conditions for exiting the charging function 2 are: the vehicle power supply is in the local ON position, the remaining power of the power battery is insufficient, the vehicle high voltage system has a fault, the DC-DC converter does not work after the vehicle enters the charging function, and the DC-DC converter starts working for more than a certain time T5 after the vehicle enters the charging function (the time T5 can be set to 0.5 to 2 hours).

[0195] S425: Each controller goes into sleep mode and enters the next wake-up cycle, waiting for the next wake-up.

[0196] This power replenishment process has ended. Except for the body controller, all other relevant controllers will go into sleep mode. The body controller will then enter the next wake-up cycle and wait for the next wake-up.

[0197] Note: The variables T1, T2, T3, T4, T5, T6, U1, U2, U3, C1, C2, C3, and F1 provided in this example are explained in the specific implementation above.

[0198] This invention provides a method for replenishing a low-voltage battery. By acquiring the first output current of a DC-DC converter (DC-DC) during the replenishment process, a first operating voltage can be determined based on the relationship between the first output current and a first preset current threshold. This allows for real-time determination of a suitable operating voltage for the DC-DC converter during low-voltage battery replenishment. By sending the first operating voltage to the DC-DC converter, the DC-DC converter replenishes the low-voltage battery according to this voltage. This real-time determination of a suitable operating voltage ensures that the DC-DC converter operates at an appropriate voltage level for replenishing the low-voltage battery. Furthermore, this method allows for real-time adjustment of the DC-DC converter's operating voltage, which helps reduce energy consumption during low-voltage battery replenishment.

[0199] Based on the same inventive concept as the foregoing embodiments, this embodiment of the invention provides a low-voltage battery charging device. This device is installed in the vehicle controller within a vehicle. The vehicle also includes a low-voltage battery and a DC-DC converter for charging the low-voltage battery. Figure 6 This is a schematic diagram of an optional low-voltage battery charging device provided in an embodiment of the present invention, as shown below. Figure 6 As shown, the device 600 may include:

[0200] The acquisition module 61 is used to acquire the first output current of the DCDC when the DCDC is replenishing the low-voltage battery;

[0201] The determining module 62 is used to determine the first operating voltage based on the relationship between the first output current and the first preset current threshold.

[0202] The power replenishment module 63 is used to send the first operating voltage to the DCDC so that the DCDC replenishes the low-voltage battery according to the first operating voltage.

[0203] In an optional embodiment, the determining module 62 is specifically used for:

[0204] The system acquires the ambient temperature outside the vehicle; determines the target correspondence based on the relationship between the first output current and the first preset current threshold; determines the operating voltage corresponding to the ambient temperature outside the vehicle based on the target correspondence; and determines the first operating voltage by summing the operating voltage corresponding to the ambient temperature outside the vehicle with the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery.

[0205] In an optional embodiment, the determining module 62 determines the target correspondence based on the magnitude relationship between the first output current and the first preset current threshold, including:

[0206] If the first output current is greater than the first preset current threshold, the first preset correspondence is determined as the target correspondence; if the first output current is less than or equal to the first preset current threshold, the second preset correspondence is determined as the target correspondence.

[0207] In an optional embodiment, the device is further used for:

[0208] After the vehicle is in the OFF position and the vehicle controller is activated, the system controls the vehicle to apply high voltage. After the high voltage is applied, a working command is sent to the DC-DC converter, so that the DC-DC converter supplies power to the low-voltage battery and the low-voltage load of the vehicle according to the second working voltage in the working command. The system obtains the second output current of the DC-DC converter during the first preset time period when it supplies power to the low-voltage battery and the low-voltage load according to the second working voltage in the working command. Based on the ratio of the duration of the second output current that is greater than the second preset current threshold to the first preset time period, the system determines whether the DC-DC converter should replenish the low-voltage battery.

[0209] In one optional embodiment, the device determines whether the DC-DC converter is replenishing the low-voltage battery based on the ratio of the duration of the current in the second output current that is greater than a second preset current threshold to a first preset time period, including:

[0210] If the duration of the current in the second output current that is greater than the second preset current threshold is greater than the ratio of the duration of the current in the first preset time period to a preset ratio, it is determined that the DC-DC converter will charge the low-voltage battery; if the duration of the current in the second output current that is less than or equal to the second preset current threshold is greater than the ratio of the duration of the current in the first preset time period to a preset ratio, it is determined that the DC-DC converter will prohibit charging the low-voltage battery.

[0211] In one optional embodiment, the second preset current threshold is equal to the sum of the third preset current threshold and the fourth preset current threshold; wherein, the third preset current threshold is: the current supplied to the low-voltage load when the DC-DC converter is charging the low-voltage battery when the vehicle is in the OFF position; the fourth preset current threshold is: the current used to charge the low-voltage battery with a set voltage when the remaining charge is set to be activated.

[0212] In one alternative embodiment, the fourth preset current threshold is related to the ambient temperature outside the vehicle.

[0213] In practical applications, the aforementioned acquisition module 61, determination module 62, and power replenishment module 63 can be implemented by a processor located on the power replenishment device 600 of the low-voltage battery, specifically a central processing unit (CPU), microprocessor (MPU), digital signal processor (DSP), or field programmable gate array (FPGA).

[0214] Figure 7 This is a schematic diagram of an optional vehicle controller provided in an embodiment of the present invention, as shown below. Figure 7As shown, an embodiment of the present invention provides a vehicle controller 700, comprising:

[0215] The processor 71 and the storage medium 72 storing instructions executable by the processor 71, the storage medium 72 performing operations via the communication bus 73 in dependence on the processor 71, when the instructions are executed by the processor 71, perform the low-voltage battery charging method described in one or more of the above embodiments.

[0216] It should be noted that in practical applications, the various components in the vehicle controller 700 are coupled together via the communication bus 73. It can be understood that the communication bus 73 is used to achieve communication between these components. In addition to the data bus, the communication bus 73 also includes a power bus, a control bus, and a status signal bus. However, for clarity, in... Figure 7 The general labeled all buses as communication bus 73.

[0217] This invention provides a vehicle, Figure 8 A schematic diagram of an optional vehicle structure is provided for an embodiment of the present invention, such as... Figure 8 As shown, vehicle 800 includes the vehicle controller 700 described in one or more of the above embodiments.

[0218] This invention provides a computer storage medium storing executable instructions. When the executable instructions are executed by one or more processors, the processors perform a low-voltage battery charging method as described in one or more of the above embodiments.

[0219] This invention provides a computer program product, including a computer program or instructions, which, when executed by a processor, implement the steps of one or more embodiments of the low-voltage battery charging method.

[0220] The computer-readable storage medium can be a magnetic random access memory (FRAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a magnetic surface memory, an optical disc, or a compact disc read-only memory (CD-ROM), etc.

[0221] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0222] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0223] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0224] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0225] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention.

Claims

1. A method for replenishing power to a low-voltage storage battery, characterized in that, The method is applied in the vehicle controller, and the vehicle further includes: the low-voltage battery and a DC-DC converter for replenishing the low-voltage battery, comprising: When the DC-DC converter is supplying power to the low-voltage battery, the first output current of the DC-DC converter is obtained; The first operating voltage is determined based on the relationship between the first output current and the first preset current threshold. The first operating voltage is sent to the DC-DC converter so that the DC-DC converter can replenish the low-voltage battery according to the first operating voltage; The step of determining the first operating voltage based on the relationship between the first output current and the first preset current threshold includes: Obtain the ambient temperature outside the vehicle; The target correspondence is determined based on the relationship between the first output current and the first preset current threshold. Based on the target correspondence, the operating voltage corresponding to the ambient temperature outside the vehicle is determined; The first operating voltage is determined by the sum of the operating voltage corresponding to the ambient temperature outside the vehicle and the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery. The target correspondence is the correspondence between ambient temperature and operating voltage; different comparison results of the magnitude relationship determine different target correspondences.

2. The method according to claim 1, characterized in that, The step of determining the target correspondence based on the magnitude relationship between the first output current and the first preset current threshold includes: If the first output current is greater than the first preset current threshold, the first preset correspondence is determined as the target correspondence. If the first output current is less than or equal to the first preset current threshold, the second preset correspondence is determined as the target correspondence.

3. The method according to claim 1 or 2, characterized in that, The method further includes: After the vehicle is in the OFF position and the vehicle controller is activated, the high voltage is applied to the vehicle. After the high voltage is completed on the vehicle, a working command is sent to the DC-DC converter so that the DC-DC converter supplies power to the low-voltage battery and the low-voltage load of the vehicle according to the second working voltage in the working command. When the DCDC supplies power to the low-voltage battery and the low-voltage load respectively according to the second operating voltage in the operating instruction, the second output current of the DCDC within a first preset time period is obtained; Based on the ratio of the duration of the second output current exceeding the second preset current threshold to the first preset time period, it is determined whether the DC-DC converter should replenish the low-voltage battery.

4. The method according to claim 3, characterized in that, The determination of whether the DC-DC converter should replenish the low-voltage battery based on the ratio of the duration of the current exceeding the second preset current threshold in the second output current to the first preset time period includes: If the duration of the second output current exceeding the second preset current threshold is greater than the proportion of the first preset time period, it is determined that the DC-DC converter is replenishing the low-voltage battery. If the duration of the second output current that is less than or equal to the second preset current threshold is greater than the ratio of the duration of the first preset time period to the preset ratio, it is determined that the DC-DC converter is prohibited from charging the low-voltage battery.

5. The method according to claim 3, characterized in that, The second preset current threshold is equal to the sum of the third preset current threshold and the fourth preset current threshold; The third preset current threshold is the current supplied to the low-voltage load when the DC-DC converter is replenishing the low-voltage battery while the vehicle is in the OFF position; the fourth preset current threshold is the current supplied to the low-voltage battery using a set voltage when the remaining charge is set to be activated for replenishment.

6. The method according to claim 5, characterized in that, The fourth preset current threshold is related to the ambient temperature outside the vehicle.

7. A charging device for a low-voltage storage battery, characterized in that, The device is installed in the vehicle's overall controller, and the vehicle further includes: the low-voltage battery and a DC-DC converter for replenishing the low-voltage battery, comprising: The acquisition module is used to acquire the first output current of the DC-DC converter when the DC-DC converter is replenishing the low-voltage battery; The determining module is used to determine the first operating voltage based on the relationship between the first output current and the first preset current threshold. A power replenishment module is used to send the first operating voltage to the DC-DC converter so that the DC-DC converter can replenish the low-voltage battery according to the first operating voltage; The determining module is used for: Obtain the ambient temperature outside the vehicle; The target correspondence is determined based on the relationship between the first output current and the first preset current threshold. Based on the target correspondence, the operating voltage corresponding to the ambient temperature outside the vehicle is determined; The first operating voltage is determined by the sum of the operating voltage corresponding to the ambient temperature outside the vehicle and the voltage drop of the line between the output terminal of the DC-DC converter and the low-voltage battery. The target correspondence is the correspondence between ambient temperature and operating voltage; different comparison results of the magnitude relationship determine different target correspondences.

8. A vehicle controller, characterized in that, include: The processor and a storage medium storing processor-executable instructions, the storage medium performing operations via a communication bus dependent on the processor, wherein when the instructions are executed by the processor, the low-voltage battery charging method according to any one of claims 1 to 6 is performed.

9. A vehicle, characterized in that, Including the vehicle controller as described in claim 8 above.

10. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by the processor, they implement the steps of the low-voltage battery charging method according to any one of claims 1 to 6.

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