Charging method and device for low-voltage storage battery, vehicle control unit and vehicle

Abstract

The embodiment of the invention discloses a charging method for a low-voltage storage battery, the method is applied to a vehicle control unit of a vehicle, the vehicle comprises the low-voltage storage battery and a DCDC for charging the low-voltage storage battery, and the charging method comprises the following steps: under the condition that the DCDC charges the low-voltage storage battery, obtaining a first output current of the DCDC, and determining a first working voltage according to a magnitude relationship between the first output current and a first preset current threshold value, and sending the first working voltage to the DCDC, so that the DCDC charges the low-voltage storage battery according to the first working voltage. The embodiment of the invention further provides a charging device of the low-voltage storage battery, a vehicle control unit and a vehicle.

Description

Technical Field

[0001] The present invention relates to a power replenishment technology for low-voltage batteries in new energy vehicles, and in particular to a power replenishment method, device, vehicle controller and vehicle for low-voltage batteries. Background Art

[0002] At present, as the degree of automobile electrification, intelligence and networking continues to deepen, the number of sensors, controllers and actuators carried by automobiles is also increasing, and the power consumption of low-voltage components in vehicles is increasing. Some new parking (OFF) gear scene functions added to new energy vehicles have accelerated the consumption of low-voltage batteries on board to a certain extent. In scenarios such as when the vehicle is parked for a long time or the driver forgets to turn off low-voltage components (such as lights) when leaving the vehicle, it may cause the low-voltage battery on board to be fed, making it difficult for the driver to start the vehicle when using it again.

[0003] Although the optional large-capacity on-board low-voltage battery will increase the vehicle's low-voltage operating time and delay the battery feeding time, it will increase the vehicle production cost and still cause battery feeding in some scenarios. Therefore, it is necessary to identify the battery feeding risk through the vehicle's electronic control unit and promptly control the vehicle's high-voltage system to power on and recharge the low-voltage battery.

[0004] In the related art, most of the charging solutions are to use the same power converter (Direct Current to Direct Current, DCDC) output voltage as when the vehicle is driving for charging. In the early stage of battery charging, different charging voltages and charging currents are used. Generally, a higher charging voltage can obtain a larger charging current, which can improve the charging efficiency. In the later stage of charging, the charging current under different voltages is relatively small. At this time, using a higher charging voltage will bring greater low-voltage load consumption. Summary of the invention

[0005] The embodiments of the present invention provide a low-voltage battery charging method, device, vehicle controller and vehicle, which can reduce the energy consumption in the charging of low-voltage batteries in new energy vehicles.

[0006] The technical solution of the present invention is achieved in this way:

[0007] An embodiment of the present invention provides a method for replenishing power of a low-voltage battery. The method is applied to a vehicle controller of a vehicle. The vehicle further includes: a low-voltage battery and a DCDC for replenishing power to the low-voltage battery, including:

[0008] When the DCDC supplies power to the low-voltage battery, obtaining a first output current of the DCDC;

[0009] Determining a first operating voltage according to a magnitude relationship between the first output current and a first preset current threshold;

[0010] The first operating voltage is sent to the DCDC, so that the DCDC replenishes power to the low-voltage battery according to the first operating voltage.

[0011] In this way, by obtaining the first output current of DCDC when DCDC is replenishing the low-voltage battery, the first operating voltage can be determined according to the magnitude relationship between the first output current and the first preset current threshold, so that the appropriate operating voltage can be determined for the DCDC in real time when replenishing the low-voltage battery; by sending the first operating voltage to DCDC, so that DCDC replenishes the low-voltage battery according to the first operating voltage, in this way, by determining the appropriate operating voltage in real time, the DCDC can operate at an appropriate operating voltage to replenish the low-voltage battery, and in this way, the operating voltage of the DCDC can be adjusted in real time, which is beneficial to reducing the energy consumption of the DCDC in replenishing the low-voltage battery.

[0012] Further, determining the first operating voltage according to the magnitude relationship between the first output current and the first preset current threshold includes:

[0013] Get the ambient temperature outside the vehicle;

[0014] Determining a target corresponding relationship according to a magnitude relationship between the first output current and the first preset current threshold;

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

[0016] The sum of the operating voltage corresponding to the ambient temperature outside the vehicle and the voltage drop of the line between the output end of the DCDC and the low-voltage battery is determined as the first operating voltage.

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

[0018] Further, according to the magnitude relationship between the first output current and the first preset current threshold, determining the target corresponding relationship includes:

[0019] When the first output current is greater than a first preset current threshold, determining the first preset corresponding relationship as a target corresponding relationship;

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

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

[0022] Furthermore, the above method also includes:

[0023] When the vehicle is in the OFF position and the vehicle controller is awakened, the vehicle is controlled to be high voltage;

[0024] After the high voltage on the vehicle is completed, a working instruction is sent to the DCDC, so that the DCDC supplies power to the low-voltage battery and the low-voltage load of the vehicle respectively according to the second working voltage in the working instruction;

[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, obtaining a second output current of the DCDC within a first preset time period;

[0026] Based on the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset period, it is determined whether the DCDC supplements the low-voltage battery.

[0027] In this way, a working instruction is sent to the DCDC to control the DCDC to supply power to the low-voltage battery and the low-voltage load, and a second output current within a first preset time period is obtained during the power supply, and the duration of the current greater than the second preset current threshold in the second output current is calculated, and the proportion of the duration in the first preset time period is calculated, and based on the proportion, it is determined whether the DCDC replenishes power to the low-voltage battery, so that it can be accurately determined whether to replenish power to the low-voltage battery.

[0028] Further, based on the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset period, determining whether the DCDC supplements the low-voltage battery includes:

[0029] When the duration of the current greater than the second preset current threshold in the second output current accounts for a proportion of the first preset period that is greater than a preset proportion, determining that the DCDC supplies power to the low-voltage battery;

[0030] When the ratio of the duration of the current less than or equal to the second preset current threshold in the second output current to the first preset period is greater than the preset ratio, it is determined that the DCDC is prohibited from supplementing the low-voltage battery.

[0031] In this way, by comparing the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset time period and the preset ratio, it is possible to determine whether the DCDC is replenishing power to the low-voltage battery, making it more accurate to determine whether the DCDC is replenishing power to the low-voltage battery.

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

[0033] Among them, the third preset current threshold is: the current used by DCDC to supply power to the low-voltage load when the vehicle is in the OFF gear; the fourth preset current threshold is: the current used to replenish the low-voltage battery using the set voltage under the set remaining power for starting the replenishment.

[0034] In this way, after testing, the above-mentioned third preset current threshold and fourth preset current threshold can be obtained, and the two are summed, and the summed value is stored locally as the second preset current threshold, which is used to determine whether the DCDC is replenishing power to the low-voltage battery, which helps to accurately determine whether the DCDC is replenishing power to the low-voltage battery.

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

[0036] In this way, the fourth preset current threshold corresponding to the ambient temperature can be determined, which is conducive to determining a more accurate second preset current threshold, and helps to improve the accuracy of whether the DCDC replenishes power to the low-voltage battery.

[0037] The embodiment of the present invention further provides a low-voltage battery charging device, which is arranged in a vehicle controller in a vehicle, and the vehicle further includes: a low-voltage battery and a DCDC for charging the low-voltage battery, including:

[0038] An acquisition module, used for acquiring a first output current of the DCDC when the DCDC supplies power to the low-voltage battery;

[0039] A determination module, configured to determine a first operating voltage according to a magnitude relationship between the first output current and a first preset current threshold;

[0040] The power replenishment module is used to send the first working voltage to the DCDC, so that the DCDC replenishes the low-voltage battery according to the first working voltage.

[0041] An embodiment of the present invention also provides a vehicle controller, comprising: a processor and a storage medium storing instructions executable by the processor, wherein the storage medium relies on the processor to perform operations through a communication bus, and 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] An embodiment of the present invention further provides a vehicle, comprising a vehicle controller as described in one or more of the above embodiments.

[0043] An embodiment of the present invention further provides a computer storage medium, characterized in that executable instructions are stored therein, and when the executable instructions are executed by a processor, the processor executes the low-voltage battery charging method as described in one or more of the above embodiments.

[0044] An embodiment of the present invention further 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, the steps of the low-voltage battery charging method described in one or more of the above embodiments are implemented.

[0045] Beneficial effects of the present invention:

[0046] (1) By obtaining a first output current of the DCDC when the DCDC is supplying power to the low-voltage battery, a first operating voltage can be determined according to a magnitude relationship between the first output current and a first preset current threshold, so that a suitable operating voltage can be determined for the DCDC in real time when supplying power to 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. In addition, the working voltage of the DCDC can be adjusted in real time, which is beneficial to reducing the energy consumption of the DCDC in replenishing the low-voltage battery. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0049] Figure 2 A schematic diagram of an example of an optional DCDC output current provided by an embodiment of the present invention;

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

[0051] Figure 4 A schematic flow chart of an example of an optional low-voltage battery charging method provided in an embodiment of the present invention;

[0052] Figure 5 A schematic flow chart of an example of an optional intelligent power replenishment demand determination method provided by an embodiment of the present invention;

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

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

[0055] Figure 8 A schematic diagram of the structure of an optional vehicle provided in an embodiment of the present invention. DETAILED DESCRIPTION

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

[0057] In view of the problem of high energy consumption in the low-voltage battery charging in the related art, an embodiment of the present invention provides a low-voltage battery charging method, which is applied to a vehicle controller of a vehicle, and the vehicle also includes: a low-voltage battery and a DCDC for charging the low-voltage battery. Figure 1 A schematic flow chart of an optional low-voltage battery charging method provided in an embodiment of the present invention, such as Figure 1 As shown, the method may include:

[0058] S101: When the DCDC is supplying power to the low-voltage battery, a first output current of the DCDC is obtained;

[0059] In order to reduce the technical problem of high energy consumption in the low-voltage battery replenishment, in an embodiment of the present invention, when DCDC replenishes the low-voltage battery, the vehicle controller obtains the output current of DCDC, which is recorded as the first output current. Here, DCDC replenishes the low-voltage battery, which can be the vehicle's power battery replenishing the low-voltage battery through DCDC, or the external charging pile replenishing the low-voltage battery through DCDC, or the vehicle's engine replenishing the low-voltage battery through DCDC. Here, the embodiment of the present invention does not make specific limitations on this.

[0060] In addition, the operating voltage of DCDC when replenishing the low-voltage battery can be recorded as the second operating voltage. In order to adjust the operating voltage of DCDC, in S101, the vehicle controller obtains the first output current of DCDC. The first output current here is the sum of the current on the low-voltage battery and the current on the low-voltage load, wherein the low-voltage load is devices such as components and controllers that require power supply other than the low-voltage battery.

[0061] S102: determining a first operating voltage according to a magnitude relationship between the first output current and a first preset current threshold;

[0062] Through S101, the vehicle controller obtains the first output current of DCDC when DCDC is replenishing power to the low-voltage battery. In S102, the first operating voltage is determined according to the magnitude 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 through the comparison result.

[0063] That is to say, the magnitude relationship between the first output current and the first preset current threshold determines that the method of determining the first operating voltage is different. For example, different corresponding relationships can be determined based on the magnitude relationship, and then the first operating voltage is determined based on the determined corresponding relationship.

[0064] S103: Sending the first working voltage to the DCDC, so that the DCDC replenishes power to the low-voltage battery according to the first working 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 DCDC, so that the DCDC can replenish the low-voltage battery according to the first operating voltage.

[0066] That is to say, in the process of DCDC replenishing the low-voltage battery, the output current of DCDC to the low-voltage battery is obtained in real time, and it is compared with the first preset current threshold to determine the working voltage of DCDC. In this way, the output voltage of DCDC can be adjusted in real time, which is beneficial to reducing the energy consumption in battery replenishment.

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

[0068] Get the ambient temperature outside the vehicle;

[0069] Determining a target corresponding relationship according to a magnitude relationship between the first output current and the first preset current threshold;

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

[0071] The sum of the operating voltage corresponding to the ambient temperature outside the vehicle and the voltage drop of the line between the output end of the DCDC and the low-voltage battery is determined as the first operating voltage.

[0072] It is understandable that the vehicle controller needs to obtain the ambient temperature outside the vehicle. Here, the ambient temperature outside the vehicle may be detected by a sensor, or by other devices. Here, the embodiment of the present invention does not specifically limit this.

[0073] After the vehicle controller obtains the ambient temperature outside the vehicle, the vehicle controller determines the target correspondence relationship based on the size relationship between the first output current and the first preset current threshold, and then determines the operating voltage corresponding to the ambient temperature outside the vehicle based on the target correspondence relationship, and takes the sum of the operating voltage corresponding to the ambient temperature outside the vehicle and the voltage drop of the line between the output end of the DCDC and the low-voltage battery as the first operating voltage.

[0074] That is to say, the target correspondence can be determined based on the magnitude relationship between the first output current and the first preset current threshold, and the target correspondence stores the correspondence between the ambient temperature and the operating voltage. Based on this, the operating voltage corresponding to the ambient temperature outside the vehicle can be determined. Then sum it with the voltage drop of the line between the output end of the DCDC and the low-voltage battery to obtain the first operating voltage. Here, the voltage drop of the line between the output end of the DCDC 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, the embodiment of the present invention does not make specific limitations on this.

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

[0076] In order to determine the target corresponding relationship, in an optional embodiment, determining the target corresponding relationship according to the magnitude relationship between the first output current and the first preset current threshold may include:

[0077] When the first output current is greater than a first preset current threshold, determining the first preset corresponding relationship as a target corresponding relationship;

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

[0079] It can be understood that 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, wherein the above-mentioned first preset correspondence and second preset correspondence are correspondences pre-stored locally.

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

[0081] Among them, ΔU is the line voltage drop from the output end of DCDC to the low-voltage battery end, which can be determined by actual vehicle measurement and testing based on the wiring harness of the actual vehicle model and the low-voltage load. U3 is the target charging voltage of the low-voltage battery. When the first output current of DCDC is greater than the DCDC output current threshold I2 (equivalent to the above-mentioned first preset current threshold), U3 is determined by checking the low-voltage battery target charging voltage table 1 under the supplementary power condition based on the ambient temperature. When the first output current of DCDC is less than or equal to the DCDC output current threshold I2, U3 is determined by checking the low-voltage battery target charging voltage table 2 under the supplementary power condition based on the ambient temperature.

[0082] Among them, the DCDC output current threshold I2 is the low-voltage battery current when the low-voltage battery is nearly fully charged (such as 80%), which is determined by testing the actual low-voltage battery. The target charging voltage table 1 of the low-voltage battery under the supplementary power condition and the target charging voltage table 2 of the low-voltage battery under the supplementary power condition are as follows:

[0083] Table 1

[0084]

[0085] Among them, the data division dimensions and filling data in Table 1 are only for the convenience of description. The actual application data dimensions and data are determined based on the actual low-voltage battery carried out testing at different ambient temperatures. The determination method of U3 in Table 1 is to charge the low-voltage battery with different voltages at the same ambient temperature, and select the voltage with the largest charging current as the target charging voltage of the low-voltage battery at the ambient temperature, and so on to determine the target charging voltage of the low-voltage battery at different ambient temperatures.

[0086] Table 2

[0087]

[0088] Among them, the data division dimensions and filling data in Table 2 are only for the convenience of description. The actual application data dimensions and data are determined based on the actual low-voltage battery carried out testing at different ambient temperatures. The determination method of U3 in Table 2 is to charge the low-voltage battery with different voltages at the same ambient temperature, and select the voltage with the highest power of the low-voltage battery after charging within the same time as the target charging voltage of the low-voltage battery at the ambient temperature, and determine the target charging voltage of the low-voltage battery at the ambient temperature by analogy.

[0089] Finally, the DCDC receives and outputs low-voltage direct current to replenish the low-voltage battery according to the target operating voltage U2 of the DCDC of the vehicle controller.

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

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

[0092] When the vehicle is in the OFF position and the vehicle controller is awakened, the vehicle is controlled to be high voltage;

[0093] After the high voltage on the vehicle is completed, a working instruction is sent to the DCDC, so that the DCDC supplies power to the low-voltage battery and to the low-voltage load of the vehicle respectively according to the second working voltage in the working instruction;

[0094] When the DCDC supplies power to the low-voltage battery and the low-voltage load of the vehicle respectively according to the second working voltage in the working instruction, obtaining a second output current of the DCDC within a first preset time period;

[0095] Based on the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset period, it is determined whether the DCDC supplements the low-voltage battery.

[0096] It can be understood that when the vehicle power is in the OFF position, the vehicle-mounted electronic control unit (for example: body domain controller (BDC), hereinafter referred to as BDC for convenience of description) that supports the timed wake-up function will wake up periodically, and wake up itself once every T1 period of time, and wake up the relevant network segments of the whole vehicle through network management (the wake-up objects at least include the vehicle control unit (VCU), battery management (BMS), DCDC, head unit (HU), onboard charger (OBC)). And detect and send the external ambient temperature to the vehicle controller.

[0097] After waking up, the vehicle controller sends a high-voltage command to the BMS to control the high voltage of the vehicle. After the high voltage of the vehicle is completed, the vehicle controller sends a command to the DCDC to instruct the DCDC to work, and sends the DCDC target working voltage U1 to the DCDC, which is recorded as the second working voltage.

[0098] After DCDC receives the working instruction and the second working voltage U1 sent by the vehicle controller, DCDC operates at the target working voltage U1 and outputs current to the low-voltage battery and the low-voltage load. DCDC detects the output current of DCDC within the first preset time period in real time, 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 the duration in the first preset time period, and determines whether the DCDC replenishes power to the low-voltage battery based on the proportion.

[0100] In this way, a working instruction is sent to the DCDC to control the DCDC to supply power to the low-voltage battery and the low-voltage load, and a second output current within a first preset time period is obtained during the power supply, and the duration of the current greater than the second preset current threshold in the second output current is calculated, and the proportion of the duration in the first preset time period is calculated, and based on the proportion, it is determined whether the DCDC replenishes power to the low-voltage battery, so that it can be accurately determined whether to replenish power to the low-voltage battery.

[0101] In order to more accurately determine whether the DCDC is replenishing power to the low-voltage battery, in an optional embodiment, based on the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset period, determining whether the DCDC is replenishing power to the low-voltage battery includes:

[0102] When the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset period is greater than the preset ratio, determining that the DCDC supplements the low-voltage battery with electricity;

[0103] When the proportion of the duration of the current less than or equal to the second preset current threshold in the second output current to the first preset period is greater than the preset proportion, it is determined that the DCDC is prohibited from supplementing the low-voltage battery.

[0104] It can be understood that the proportion of the duration of the current greater than the second preset current threshold in the second output current to the first preset time period is calculated. If, after comparison, the proportion is greater than the preset proportion, it means that the duration of the current greater than the second preset current threshold in the first preset time period accounts for a large proportion, so it is determined that DCDC replenishes the low-voltage battery. If, after comparison, the proportion is less than or equal to the preset proportion, it means that the duration of the current greater than the second preset current threshold in the first preset time period accounts for a small proportion, so it is determined that DCDC is prohibited from replenishing the low-voltage battery.

[0105] The above preset ratio may be 70%.

[0106] In this way, by comparing the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset time period and the preset ratio, it is possible to determine whether the DCDC is replenishing power to the low-voltage battery, making it more accurate to determine whether the DCDC is replenishing power to the low-voltage battery.

[0107] With respect to the above-mentioned second preset current threshold, in an 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] It can be understood that the above-mentioned second preset current threshold is the sum of the third preset current threshold and the fourth current threshold, wherein the third preset current threshold is: the current used by the DCDC to supply power to the low-voltage load when the vehicle is in the OFF gear to replenish the low-voltage battery; the fourth preset current threshold is: the current used to replenish the low-voltage battery using the set voltage under the set remaining power for starting the replenishment.

[0109] That is to say, after the third preset current threshold and the fourth preset current threshold are obtained through testing, the two are summed and the summed value is stored locally as the second preset current threshold, which is used to determine whether the DCDC is replenishing power to the low-voltage battery, which helps to accurately determine whether the DCDC is replenishing power to the low-voltage battery.

[0110] With respect to the fourth preset current threshold, in an optional embodiment, the fourth preset current threshold is related to the ambient temperature outside the vehicle.

[0111] It can be understood that in the process of determining the fourth preset current threshold by testing, the fourth preset current threshold determined by different ambient temperatures is different, which means that the fourth preset current threshold is related to the ambient temperature outside the vehicle.

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

[0113] In this way, the fourth preset current threshold corresponding to the ambient temperature can be determined, which is conducive to determining a more accurate second preset current threshold, and helps to improve the accuracy of whether the DCDC replenishes power to the low-voltage battery.

[0114] For example, when the vehicle is in the OFF gear and the vehicle controller is awakened, the vehicle controller sends a high-voltage command to the BMS to control the high voltage of the vehicle. After the vehicle high voltage is completed, the vehicle controller sends a command to the DCDC to instruct the DCDC to work, and sends the DCDC target working voltage U1 (equivalent to the above-mentioned second working voltage) to the DCDC. After the DCDC receives the working command and the DCDC target working voltage U1 sent by the vehicle controller, the DCDC works at the target working voltage U1 and outputs current to power the battery and low-voltage load. The DCDC detects in real time and sends the DCDC output current to the vehicle controller.

[0115] The vehicle controller receives the DCDC output current in the time period T3 (equivalent to the above-mentioned first preset time period) after the DCDC working instruction is sent, and calculates the time T4 when the DCDC output current is greater than the DCDC output current threshold I1 (equivalent to the above-mentioned second preset current threshold). 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 of an example of an optional DCDC output current provided by an embodiment of the present invention, such as Figure 2 As shown, the output current change of DCDC in T3. It can be seen that the period greater than I1 includes L2 and L4, so T4 can be calculated as follows: T4=L2+L4.

[0117] For example, two DCDC output current thresholds I1 and I2 may be set (wherein the DCDC output current threshold I1>I2).

[0118] DCDC output current threshold I1 = I11 + I12. Among them, I11 is the sum of the low-voltage load terminal currents other than the battery when replenishing power in the OFF gear, which is determined by testing based on the actual vehicle model. I12 is the low-voltage battery terminal current that uses a constant voltage to charge the battery at the set remaining power of the low-voltage battery that needs to be replenished (for example, if the low-voltage battery is set to need to be replenished when the remaining power is 50%, the test is carried out at a constant voltage U1 and temperature W1 to measure the current size when charging the battery with a remaining power of 50%).

[0119] The magnitude of the low-voltage battery charging current is affected by factors such as the charging voltage, the charge amount of the low-voltage battery and the temperature. Therefore, based on the ambient temperature detected by the body controller, the DCDC output current when the low-voltage battery needs to be recharged is looked up in a table to obtain the DCDC output current threshold I1. As shown in Table 3:

[0120] Table 3

[0121]

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

[0123] The following is an example to describe the method for charging a low-voltage battery described in one or more of the above embodiments.

[0124] Figure 3 A schematic diagram of an example of an optional intelligent power replenishment system provided by an embodiment of the present invention is shown as follows: Figure 3 As shown, the intelligent charging system 300 may include: a low-voltage battery 31, a DCDC32, a power battery pack 33, an OBC34, a BMS35, a BDC36, a HU37, a VCU38, an engine controller 39, a motor controller 40, a motor 41, and an engine 42; wherein, a high-voltage, low-voltage, and communication connection is established between the OBC34 and the charging pile 301; a mechanical connection is established between the motor 41 and the engine; a high-voltage connection is established between the power battery pack 33 and the DCDC32, the motor 40, and the OBC34 respectively; a low-voltage connection is established between the power battery pack 33 and the BMS35; a low-voltage connection is established between the engine 42 and the engine controller 40; a low-voltage connection is established between the DCDC32 and the low-voltage battery 31; a low-voltage connection is established between the low-voltage battery 31 and the BDC36; and a communication connection is established between the DCDC32, the BMS35, the motor controller 40, the engine controller 39, the VCU38, the HU37, and the BDC36.

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

[0126] S401: The vehicle body controller wakes up periodically, wakes up the vehicle network through network management, detects and sends the ambient temperature to the vehicle controller;

[0127] Here, when the vehicle is powered off and the power gear is in the OFF position, the vehicle-mounted electronic control unit (for example: BDC, for convenience of description, this controller is referred to as BDC) that supports the timed wake-up function will periodically wake up, and wake up once every T1 period of time, and wake up the relevant network segments of the vehicle through network management (the wake-up objects include at least VCU, BMS, DCDC, HU, OBC). And detect and send the external ambient temperature to the vehicle controller.

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

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

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

[0131] Here, the method for calculating the vehicle power-off duration is as follows: when the vehicle is powered off, the HU stores the time point t0 at that moment. When the vehicle power gear is in the OFF gear, when the HU is awakened, the current time t1 is subtracted from the stored power-off time point t0 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] Among them, after waking up, the vehicle controller receives and determines the connection status of the AC charging gun. For example, if the AC charging gun status sent by the BMS is in a connected state and not in charging, the vehicle controller enters the connected charging mode and executes S404; otherwise, the vehicle controller enters the non-connected charging mode and executes S4031.

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

[0135] S404: The vehicle controller determines whether the current vehicle state condition 1 is satisfied. If yes, execute S405; if no, execute S4025;

[0136] Specifically, in the charging mode of charging with a charging pile, the vehicle controller determines whether the current vehicle state condition 1 is satisfied. For example, if the vehicle state condition 1 is satisfied, S405 is executed to determine whether the battery has a smart charging demand. Otherwise, S4025 is executed.

[0137] Among them, vehicle status condition 1 includes whether the current vehicle power gear is OFF, whether the vehicle power-off time exceeds 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 for power-off to avoid the driver's active need to lower the high voltage. During this time period, charging should not be allowed. It can be evaluated based on actual usage and is generally defined between 15 and 30 minutes. Threshold C1 is the power battery self-protection SOC value, which is generally 20%.

[0139] S405: The vehicle controller determines whether the low-voltage battery has a need for intelligent charging; if yes, execute S406; if no, execute S4025;

[0140] Figure 5 An example flow chart of an optional intelligent power replenishment demand determination method provided by an embodiment of the present invention is as follows: Figure 5 As shown, the method may include:

[0141] S501: The vehicle controller sends a high-voltage command to the BMS to control the high voltage of the vehicle. After the high voltage is applied to the vehicle, the vehicle controller sends a command to the DCDC to instruct the DCDC to work and output current;

[0142] The vehicle controller sends a command to the DCDC to instruct the DCDC to work and output current, and sends the DCDC target working voltage U1 to the DCDC. U1 is the target working voltage sent by the vehicle controller to the DCDC under normal driving conditions, which is a fixed value.

[0143] S502: DCDC detects in real time and sends the DCDC output current to the vehicle controller;

[0144] After receiving the working instruction and DCDC target working voltage sent by the vehicle controller, DCDC works at the target working voltage and outputs current to power the battery and low-voltage load. DCDC detects in real time and sends the DCDC output current to the vehicle controller.

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

[0146] Among them, the vehicle controller receives the DCDC output current within the time period T3 after the DCDC working instruction is sent, and determines and calculates the time T4 when the DCDC output current is greater than the DCDC output current threshold I1. If T4 / T3 is greater than 70%, the vehicle controller determines that there is a need for intelligent power replenishment and executes S406; wherein, the time period T3 generally takes a value of 60 to 90s. Otherwise, the vehicle controller determines that there is no need for intelligent power replenishment and executes S4025. The specific method for calculating the intelligent power replenishment demand refers to the above-mentioned low-voltage battery power replenishment method, which will not be repeated here.

[0147] S406: The vehicle controller sends a charging request to the BMS as a request;

[0148] Among them, in the charging mode of connecting to the charging pile, when the vehicle controller determines that there is a demand for intelligent charging, it sends a charging request to the BMS as a request.

[0149] S407: After receiving the request for charging only to supplement the power, the BMS sends a work request instruction to the OBC, and after the OBC enters the working state, sends a high-voltage request for charging only to supplement the power to the vehicle controller;

[0150] That is to say, after BMS receives the request for charging only to replenish power, it sends a work request instruction to OBC, and after OBC enters the working state, it sends a request for charging only to replenish power under high voltage to the vehicle controller.

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

[0152] S4081: When the vehicle controller receives the high-voltage lowering request for charging only and replenishing electricity from the BMS, it sends a high-voltage lowering instruction to the BMS to control the vehicle to lower the high voltage;

[0153] Among them, when the vehicle controller receives the request for charging only and lowering high voltage sent by the BMS, the vehicle controller sends a high-voltage lowering instruction to the BMS to control the power battery to lower the high voltage.

[0154] S4082: The vehicle controller determines whether the BMS charging only supplementary power high voltage request is not a request for more than time T6? If yes, execute S415; if no, return to execute S408;

[0155] Specifically, when the vehicle controller receives the charging-only high-voltage request from the BMS and there is no request for more than a certain time T6, it goes to S4015; among which, time T6 is the action time for BMS to request OBC to work and OBC to enter the working state and make corresponding feedback to BMS, which is evaluated according to actual usage and is generally defined as 20 to 60s.

[0156] S409: BMS sends the external charging demand current and voltage to OBC, and OBC converts the charging pile power into direct current;

[0157] Among them, BMS sends the external charging demand current and voltage to the on-board charger OBC, and OBC converts the charging pile power into direct current according to the request of BMS.

[0158] S410: The vehicle controller enters the intelligent charging mode and calculates the charging duration. The vehicle controller calculates the DCDC target operating voltage in real time and sends it to the DCDC.

[0159] When the battery is under high voltage and the OBC is in the working output state, the vehicle controller enters the intelligent charging function and starts to count the charging time. At the same time, the vehicle controller calculates the DCDC target working voltage U2 based on the DCDC current, ambient temperature and other conditions, and sends it to the DCDC. The calculation method of the DCDC target working voltage U2 refers to the charging method of the low-voltage battery mentioned above, which will not be repeated here.

[0160] S411: DCDC receives the target operating voltage of the vehicle controller DCDC, and DCDC converts the high-voltage DC power into low-voltage DC power to supplement the low-voltage battery;

[0161] S412: The vehicle controller determines whether the charging exit condition 1 is met. If yes, execute S4121; if no, execute S410;

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

[0163] That is to say, if the charging exit condition 1 is met, the vehicle controller sends a charging only charging request to the BMS as no request. Otherwise, the process returns to S410 and continues to maintain the charging.

[0164] Among them, the power replenishment exit condition 1 refers to: the vehicle power gear is in the local ON gear, there is a fault in the vehicle high-voltage system, the DCDC does not work after the vehicle enters the power replenishment function, and the DCDC starts working for more than a certain time T5 after the vehicle enters the power replenishment function (time T5 can be set to 0.5~2h).

[0165] S413: After receiving the charging only supplementary power request as no request, the BMS sends a command to the OBC to control the OBC to stop working.

[0166] S414: The vehicle controller exits the intelligent charging function, the vehicle lowers the high voltage, and executes S425.

[0167] S415: The vehicle controller sends a charging request to the BMS as no request;

[0168] In the charging pile connected power replenishment mode, after the vehicle controller sends a charging and replenishment request to the BMS as a request, the BMS request to OBC fails, the BMS does not send a charging and replenishment under high voltage request to the vehicle controller, the vehicle controller receives the charging and replenishment under high voltage request sent by the BMS as no request for more than a certain time T6, then the vehicle controller sends a charging and replenishment under high voltage request to the BMS as no request.

[0169] S416: After receiving the charging only supplementary power request as no request, the BMS sends a command to the OBC to control the OBC to stop working;

[0170] After the BMS receives the charging request from the vehicle controller, it sends a command to the OBC to control the OBC to stop working. Then the vehicle controller determines the charging condition in the non-connected charging mode.

[0171] S417: The vehicle controller determines whether the vehicle status condition 2 is satisfied. If yes, execute S4171; if no, execute S414;

[0172] S4171: The vehicle controller determines whether the low-voltage battery has an intelligent charging request. If yes, execute S410; if no, execute S425;

[0173] Among them, if the result of the vehicle status condition 2 is satisfied, the vehicle controller determines whether the low-voltage battery has a need for intelligent charging. Otherwise, it goes to S414, and the vehicle controller controls the exit of the intelligent charging function. (The above-mentioned low-voltage battery charging method for intelligent charging demand judgment method is not repeated here).

[0174] Among them, vehicle status condition 2 includes whether the current vehicle power gear is OFF, whether the vehicle power-off time exceeds 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 computer wakes up, the driver's power-on setting (allowed / not allowed) is detected in real time and sent to the vehicle controller;

[0176] The vehicle computer provides a setting switch in the user interface to indicate whether the engine is allowed to be started during the corresponding charging process (reference for the setting switch options for starting the engine during charging: allow / do not allow). After the driver selects the corresponding setting option (such as allow / do not allow), the vehicle computer will store the charging starting setting and send the setting information to the vehicle controller in real time.

[0177] S419: After the vehicle is powered off, the vehicle computer should store the power-on and engine-starting setting information before going into sleep mode.

[0178] S420: The vehicle controller enters the intelligent charging mode and calculates the charging duration. The vehicle controller calculates the DCDC target operating voltage and sends it to the DCDC.

[0179] In the non-connected charging mode, when the vehicle controller determines that there is a need for intelligent charging, the vehicle controller enters the intelligent charging function and starts timing the charging time. At the same time, the vehicle controller calculates the DCDC target operating voltage U2 based on the DCDC current, ambient temperature and other conditions, and sends it to the DCDC. The calculation method of the DCDC target operating voltage U2 refers to the charging method of the low-voltage battery mentioned above, which will not be repeated here.

[0180] S421: DCDC receives the target operating voltage of the vehicle controller DCDC, and DCDC converts the high-voltage direct current into low-voltage direct current to supplement the low-voltage battery;

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

[0182] Among them, after the intelligent charging function is successfully started, during the process of DCDC working to charge the battery, the vehicle controller receives and determines the charging start engine setting signal and the remaining power of the power battery sent by the vehicle computer;

[0183] S4221: The vehicle controller controls the remote starter to generate electricity to charge the power battery;

[0184] For example, if the battery starting engine setting signal sent by the vehicle computer allows the engine to be started and the remaining power of the power battery is less than the remaining power limit C2 of the battery starting engine and the current remaining fuel is greater than the limit F1, the vehicle controller controls the remote starting engine to drive the motor to generate electricity to charge the power battery.

[0185] Among them, the remaining power limit C2 of the power battery for starting the engine with supplementary power can be set to 23%, and the remaining fuel limit F1 for starting the engine with supplementary power can be set to 9L. There is no limit on the specific values ​​for executing the function.

[0186] S423: The vehicle controller determines whether the power battery SOC is greater than the limit value C3. If yes, execute S4231; if no, execute S424;

[0187] During the intelligent charging process, after starting the engine to generate electricity to charge the power battery, the vehicle controller receives and determines the remaining power of the power battery.

[0188] S4231: The vehicle controller controls the remote engine to exit and stop the engine;

[0189] When the remaining power of the power battery is greater than the remaining power limit C3 for exiting the power supplementation starting engine, the vehicle controller controls the exit of the remote starting engine and stops the engine.

[0190] Among them, the remaining power limit C3 of the engine power battery for exiting the power supplement and starting can be set to 28%, and there is no limit on the specific value of the function execution.

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

[0192] S4241: The vehicle controller controls the exit of the remote engine start function, stops the engine, and exits the power replenishment function, and the vehicle is under high voltage;

[0193] If the charging exit condition 2 is met, the vehicle controller ensures that the charging remote engine start state is exited (for example, after the engine is started based on the charging function, the remaining power of the power battery is not greater than the remaining power limit C3 of the power battery for exiting the charging start engine, so that the engine is still in the running state, the vehicle controller controls the exit of the remote engine start and stops the engine), the vehicle controller controls the exit of the intelligent charging function, sends the vehicle high voltage command to the power battery management system BMS, and controls the vehicle to lower the high voltage. If the charging exit condition 2 is not met, it returns to continue to execute S420.

[0194] Among them, meeting the power replenishment exit condition 2 means: the vehicle power gear is in the local ON gear, the remaining power of the power battery is insufficient, there is a fault in the vehicle high-voltage system, the DCDC does not work after the vehicle enters the power replenishment function, and the DCDC starts working for more than a certain time T5 after the vehicle enters the power replenishment function (time T5 can be set to 0.5~2h).

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

[0196] After the power replenishment process is completed, all related controllers except the body controller go into sleep mode, and the body controller enters the next wake-up cycle timing, waiting 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 correspondingly described in the specific implementation manner above.

[0198] An embodiment of the present invention provides a method for replenishing power of a low-voltage battery. By obtaining a first output current of a DCDC when the DCDC replenishes power to the low-voltage battery, a first operating voltage can be determined according to a magnitude relationship between the first output current and a first preset current threshold. In this way, a suitable operating voltage can be determined for the DCDC in real time when replenishing power to the low-voltage battery; by sending the first operating voltage to the DCDC, the DCDC replenishes power to the low-voltage battery according to the first operating voltage. In this way, by determining a suitable operating voltage in real time, the DCDC can operate at a suitable operating voltage to replenish power to the low-voltage battery. In addition, the operating voltage of the DCDC can be adjusted in real time, which is beneficial to reducing energy consumption when the DCDC replenishes power to the low-voltage battery.

[0199] Based on the same inventive concept as the above-mentioned embodiment, an embodiment of the present invention provides a low-voltage battery charging device, which is arranged in a vehicle controller in a vehicle, and the vehicle further includes: a low-voltage battery and a DCDC for charging the low-voltage battery. Figure 6 A schematic diagram of the structure of an optional low-voltage battery charging device provided in an embodiment of the present invention, such as Figure 6 As shown, the apparatus 600 may include:

[0200] An acquisition module 61 is used to acquire a first output current of the DCDC when the DCDC supplies power to the low-voltage battery;

[0201] A determination module 62, configured to determine a first operating voltage according to a magnitude relationship between the first output current and a first preset current threshold;

[0202] The charging module 63 is used to send the first working voltage to the DCDC, so that the DCDC charges the low-voltage battery according to the first working voltage.

[0203] In an optional embodiment, the determination module 62 is specifically configured to:

[0204] Acquire the ambient temperature outside the vehicle; determine a target correspondence relationship based on a magnitude relationship between a first output current and a first preset current threshold; determine an operating voltage corresponding to the ambient temperature outside the vehicle based on the target correspondence relationship; and determine the sum of the operating voltage corresponding to the ambient temperature outside the vehicle and a voltage drop of a line between an output end of the DCDC and a low-voltage battery as the first operating voltage.

[0205] In an optional embodiment, the determination module 62 determines the target corresponding relationship according to the magnitude relationship between the first output current and the first preset current threshold, including:

[0206] When the first output current is greater than the first preset current threshold, the first preset corresponding relationship is determined as the target corresponding relationship; when the first output current is less than or equal to the first preset current threshold, the second preset corresponding relationship is determined as the target corresponding relationship.

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

[0208] When the vehicle is in the OFF gear and the vehicle controller is awakened, the high voltage on the vehicle is controlled; after the high voltage on the vehicle is completed, a working instruction is sent to the DCDC, so that the DCDC supplies power to the low-voltage battery and the low-voltage load of the vehicle respectively according to the second working voltage in the working instruction; the second output current within a first preset time period 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 is obtained; based on the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset time period, it is determined whether the DCDC replenishes power to the low-voltage battery.

[0209] In an optional embodiment, the device determines whether the DCDC is replenishing power to the low-voltage battery based on the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset period, including:

[0210] When the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset time period is greater than the preset ratio, it is determined that the DCDC replenishes the low-voltage battery; when the ratio of the duration of the current less than or equal to the second preset current threshold in the second output current to the first preset time period is greater than the preset ratio, it is determined that the DCDC is prohibited from replenishing the low-voltage battery.

[0211] In an 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 used by the DCDC to supply power to the low-voltage load when the vehicle is in the OFF gear; the fourth preset current threshold is: the current used to replenish the low-voltage battery using a set voltage at the set remaining power for starting the replenishment.

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

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

[0214] Figure 7 A schematic diagram of the structure of an optional vehicle controller provided by an embodiment of the present invention is shown in FIG. Figure 7As shown, an embodiment of the present invention provides a vehicle controller 700, including:

[0215] A processor 71 and a storage medium 72 storing executable instructions of the processor 71, wherein the storage medium 72 relies on the processor 71 to perform operations through a communication bus 73, and when the instructions are executed by the processor 71, the low-voltage battery charging method described in one or more of the above embodiments is executed.

[0216] It should be noted that in actual application, the various components in the vehicle controller 700 are coupled together through the communication bus 73. It is understandable that the communication bus 73 is used to realize the connection and 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 the sake of clarity, Figure 7 Various buses are labeled as communication buses 73.

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

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

[0219] An embodiment of the present invention provides a computer program product, including a computer program or instructions, which, when executed by a processor, implements the steps of the low-voltage battery charging method described in one or more embodiments.

[0220] Among them, the computer-readable storage medium can be a ferromagnetic 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 disk, or a compact disc read-only memory (CD-ROM) and other memories.

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

[0222] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0223] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0224] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

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

Claims

1. A method for replenishing power of a low-voltage battery, characterized in that: The method is applied to a vehicle controller of a vehicle, wherein the vehicle further comprises: the low-voltage battery and a DCDC for replenishing power to the low-voltage battery, comprising: When the DCDC supplies power to the low-voltage battery, obtaining a first output current of the DCDC; Determining a first operating voltage according to a magnitude relationship between the first output current and a first preset current threshold; The first operating voltage is sent to the DCDC, so that the DCDC replenishes power to the low-voltage battery according to the first operating voltage.

2. The method according to claim 1, characterized in that The determining of the first operating voltage according to the magnitude relationship between the first output current and a first preset current threshold comprises: Acquiring the ambient temperature outside the vehicle; Determining a target corresponding relationship according to a magnitude relationship between the first output current and a first preset current threshold; Based on the target corresponding relationship, determining 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 end of the DCDC and the low-voltage battery is determined as the first operating voltage.

3. The method according to claim 2, characterized in that The determining of the target corresponding relationship according to the magnitude relationship between the first output current and the first preset current threshold value includes: In a case where the first output current is greater than the first preset current threshold, determining the first preset corresponding relationship as the target corresponding relationship; When the first output current is less than or equal to the first preset current threshold, a second preset corresponding relationship is determined as the target corresponding relationship.

4. The method according to any one of claims 1 to 3, characterized in that: The method further comprises: When the vehicle is in the OFF gear and the vehicle controller is awakened, controlling the vehicle to be high voltage; After the high voltage on the vehicle is completed, sending a working instruction to the DCDC, so that the DCDC supplies power to the low-voltage battery and the low-voltage load of the vehicle respectively according to the second working voltage in the working instruction; 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, obtaining a second output current of the DCDC within a first preset time period; Based on the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset period, it is determined whether the DCDC supplements the low-voltage battery.

5. The method according to claim 4, characterized in that The determining whether the DCDC supplies power to the low-voltage battery based on the ratio of the duration of the current greater than the second preset current threshold in the second output current to the first preset period includes: When the duration of the current greater than the second preset current threshold in the second output current accounts for a proportion greater than a preset proportion of the first preset period, determining that the DCDC supplies power to the low-voltage battery; When the ratio of the duration of the current less than or equal to the second preset current threshold in the second output current to the first preset period is greater than the preset ratio, it is determined that the DCDC is prohibited from supplementing the low-voltage battery.

6. The method according to claim 4, 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; Among them, the third preset current threshold is: the current of the DCDC supplying power to the low-voltage load when the vehicle is in the OFF gear; the fourth preset current threshold is: the current of the low-voltage battery using the set voltage under the set remaining power for starting the replenishment.

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

8. A low-voltage battery charging device, characterized in that: The device is arranged in a vehicle controller in a vehicle, and the vehicle further comprises: the low-voltage battery and a DCDC for replenishing power to the low-voltage battery, comprising: An acquisition module, used for acquiring a first output current of the DCDC when the DCDC supplies power to the low-voltage battery; A determination module, configured to determine a first operating voltage according to a magnitude relationship between the first output current and a first preset current threshold; The power replenishment module is used to send the first working voltage to the DCDC, so that the DCDC replenishes power to the low-voltage battery according to the first working voltage.

9. A vehicle controller, characterized in that: include: A processor and a storage medium storing instructions executable by the processor, wherein the storage medium relies on the processor to perform operations through a communication bus, and when the instructions are executed by the processor, the low-voltage battery charging method described in any one of claims 1 to 7 is executed.

10. A vehicle, characterized in that: It includes the vehicle controller as described in claim 9 above.

11. A computer program product comprising a computer program or instructions, characterized in that When the computer program or instruction is executed by the processor, the steps of the low-voltage battery charging method according to any one of claims 1 to 7 are implemented.

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