Automobile power supply system

Abstract

The invention discloses an automobile power supply system, which comprises a battery pack, a voltage conversion unit and a power supply switching unit, and is characterized in that a first power supply end formed by all battery units of the battery pack supplies power to a low-voltage load after passing through the voltage conversion unit; in addition, the second power supply end formed by part of the battery units of the battery pack supplies power to the low-voltage load, and the first power supply end or the second power supply end is selected to supply power to the low-voltage load through the power supply switching unit, so that on one hand, a low-voltage storage battery can be omitted, and only the battery pack serving as a power battery is arranged to supply power to the low-voltage load; therefore, the use and maintenance cost is reduced; on the other hand, the first power supply end (powered by the whole battery pack) and the second power supply end (powered by part of the battery pack) can be mutually active and standby, so that influence on power supply to the low-voltage load due to partial damage of the battery pack is reduced, and stable power supply to the low-voltage load is guaranteed. The invention is widely applied to the technical field of automobiles.

Description

Technical Field

[0001] The invention relates to the technical field of automobiles, in particular to an automobile power supply system. Background Art

[0002] The operating voltage of the electrical loads such as the lights, air conditioners, audio and video entertainment systems and windows on the car is generally at the level of 12V, which are generally referred to as low-voltage loads; the operating voltage of the electrical loads such as the motor used to drive the wheels on the car is at the level of hundreds of volts (the operating voltage of the motor of a mild hybrid car is generally 48V), which can be called high-voltage loads. Electric vehicles (including pure electric vehicles, hybrid vehicles, mild hybrid vehicles, etc.) are equipped with both low-voltage loads and high-voltage loads. In the current electric vehicle technology, it is necessary to set up a power supply system for low-voltage loads and high-voltage loads respectively, which has high use and maintenance costs. Summary of the invention

[0003] In view of the technical problems that current automobile technology requires a power supply system for low-voltage loads and high-voltage loads respectively, and the high cost of use and maintenance, the object of the present invention is to provide an automobile power supply system.

[0004] The embodiment of the present invention includes a battery pack; the battery pack includes a plurality of battery cells, a first power supply end and a second power supply end; the first power supply end is formed by combining all the battery cells in series and / or in parallel, and the second power supply end is formed by a single battery cell, or by combining some of the battery cells in series and / or in parallel;

[0005] A voltage conversion unit; the input end of the voltage conversion unit is connected to the first power supply end, and the voltage conversion unit is used to perform voltage conversion;

[0006] A power supply switching unit; a first input end of the power supply switching unit is connected to the output end of the voltage conversion unit, a second input end of the power supply switching unit is connected to the second power supply end, and an output end of the power supply switching unit is used to connect to a low-voltage load of a car; the power supply switching unit is used to switch the output end of the power supply switching unit to be connected to the first input end or the second input end.

[0007] In this embodiment, the automobile power supply system further includes:

[0008] Battery management system; the input end of the battery management system is connected to the first power supply end, and the output end of the battery management system is used to connect to the high-voltage load of the car.

[0009] In this embodiment, switching the output end of the power supply switching unit to be connected to the first input end or the second input end includes:

[0010] Detecting the working state of the voltage conversion unit;

[0011] When the working state of the voltage conversion unit is normal, the output end of the power supply switching unit is switched to be connected to the first input end.

[0012] In this embodiment, switching the output end of the power supply switching unit to be connected to the first input end or the second input end includes:

[0013] When the working state of the voltage conversion unit is abnormal, the output end of the power supply switching unit is switched to be connected to the second input end.

[0014] In this embodiment, the automobile power supply system further includes:

[0015] A battery partitioning unit; the battery partitioning unit is used to partition each of the battery cells in the battery pack, determine at least one target battery cell, connect the output end of a single target battery cell as the second power supply end, or connect the output ends of multiple target battery cells in series and / or parallel as the second power supply end.

[0016] In this embodiment, partitioning the battery cells in the battery pack to determine at least one target battery cell includes:

[0017] Divide into multiple time periods;

[0018] For any of the time periods, load balancing corresponding to the time period is performed on each of the battery units, and the target battery unit corresponding to the time period is determined according to the result of the load balancing.

[0019] In this embodiment, for any of the time periods, load balancing corresponding to the time period is performed on each of the battery cells, and the target battery cell corresponding to the time period is determined according to the result of the load balancing, including:

[0020] Obtaining low-voltage load record information corresponding to each of the battery units at the start time of the time period; the low-voltage load record information represents a load record of the battery unit discharging a low-voltage load of a vehicle;

[0021] Filtering out at least one of the lowest low-voltage load record information;

[0022] The battery cell corresponding to the filtered low-voltage load record information is determined as the target battery cell.

[0023] In this embodiment, for any of the time periods, load balancing corresponding to the time period is performed on each of the battery cells, and the target battery cell corresponding to the time period is determined according to the result of the load balancing, including:

[0024] Acquire high-voltage load record information corresponding to each of the battery units at the start time of the time period; the high-voltage load record information represents a load record of the battery unit discharging the high-voltage load of the vehicle;

[0025] Filter out the lowest at least one of the high voltage load record information;

[0026] The battery cell corresponding to the filtered high-voltage load record information is determined as the target battery cell.

[0027] In this embodiment, for any of the time periods, load balancing corresponding to the time period is performed on each of the battery cells, and the target battery cell corresponding to the time period is determined according to the result of the load balancing, including:

[0028] Obtaining low-voltage load record information and high-voltage load record information corresponding to each of the battery units at the start time of the time period; the low-voltage load record information represents a load record of the battery unit discharging the low-voltage load of the vehicle, and the high-voltage load record information represents a load record of the battery unit discharging the high-voltage load of the vehicle;

[0029] Determine the total load record information corresponding to the same battery unit according to the low-voltage load record information and the high-voltage load record information corresponding to the same battery unit;

[0030] Filter out at least one of the total load record information with the lowest value;

[0031] The battery cell corresponding to the filtered total load record information is determined as the target battery cell.

[0032] In this embodiment, determining the total load record information corresponding to the same battery unit according to the low voltage load record information and the high voltage load record information corresponding to the same battery unit includes:

[0033] For any of the battery cells, obtaining health information and temperature information of the battery cell;

[0034] Determining a first weight of the battery cell according to the health information; the first weight is negatively correlated with the health information;

[0035] Determining a second weight of the battery cell according to the temperature information; the second weight is positively correlated with the temperature information;

[0036] The low-voltage load record information and the high-voltage load record information are weighted and summed according to the first weight and the second weight to obtain the total load record information.

[0037] The beneficial effects of the present invention are as follows: through the automobile power supply system in the embodiment, the first power supply end formed by all the battery cells of the battery pack can supply power to the low-voltage load after passing through the voltage conversion unit, and the second power supply end formed by part of the battery cells of the battery pack can supply power to the low-voltage load. The power supply switching unit selects the first power supply end or the second power supply end to supply power to the low-voltage load. On the one hand, it is unnecessary to set up a low-voltage battery, and only the battery pack as a power battery is set up to supply power to the low-voltage load, thereby reducing the use and maintenance costs; on the other hand, the first power supply end (powered by the entire battery pack) and the second power supply end (powered by part of the battery pack) can serve as a primary and a backup for each other, reducing the impact of partial damage to the battery pack on the power supply to the low-voltage load, and ensuring the stability of the power supply to the low-voltage load. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 and Figure 2 It is a schematic diagram of the principle of the related technology;

[0039] Figure 3 It is a structural schematic diagram of the automobile power supply system in the embodiment;

[0040] Figure 4 A schematic diagram of the structure of a vehicle power supply system provided with a battery management system in an embodiment;

[0041] Figure 5 Schematic diagram of the structure of the automobile power supply system provided with a battery partition unit in the embodiment. DETAILED DESCRIPTION

[0042] Current automotive power supply related technologies such as Figure 1 As shown, a high-voltage power battery (including multiple battery cell groups, generally a lithium battery) is used to power the high-voltage load, and a separate low-voltage battery (generally a lead-acid battery) is used to power the low-voltage load. Since a high-voltage power battery and a low-voltage load need to be set up, the cost of use and maintenance is relatively high.

[0043] Can Figure 1 The automotive power supply system shown in the figure is improved to obtain Figure 2 The automotive power supply system shown. Figure 2 The vehicle power supply system shown is similar to Figure 1 Compared with the automotive power supply system shown in the figure, the low-voltage battery is eliminated, and a PACK DC-DC module is integrated into the high-voltage power battery. The PACK DC-DC module can convert the high-voltage electricity output by the battery pack into low-voltage electricity for use by low-voltage loads. Figure 2 The vehicle power supply system shown eliminates the low voltage battery, thereby reducing the use and maintenance costs.

[0044] However, since high-voltage power batteries need to supply power to the vehicle's power system, performance loss is relatively large. Also, since high-voltage power batteries are generally lithium batteries with strong activity, the stability of high-voltage power batteries is poorer than that of low-voltage batteries. Figure 2 The vehicle power supply system shown in the figure eliminates the stable low-voltage battery, and the low-voltage load is powered by the more unstable high-voltage power battery, which faces greater instability in the power supply to the low-voltage load. Since the low-voltage load is related to basic functions such as vehicle control, Figure 2 In the automobile power supply system shown, the basic functional stability of the automobile is poor.

[0045] Based on the above principle, in this embodiment, a vehicle power supply system is provided. The structure of the vehicle power supply system is as follows: Figure 3 shown.

[0046] Reference Figure 3 The automobile power supply system includes a battery pack, a voltage conversion unit and a power supply switching unit. On this basis, the automobile power supply system can also be equipped with a battery management system (BMS) and a battery partition unit.

[0047] Reference Figure 3 The battery pack in the automobile power supply system includes a plurality of battery cells. Specifically, Figure 3 The battery pack in the figure can be the whole power battery. If the power battery structure of CMP (i.e. the three-level structure of cell, module and pack) is used, then Figure 3 The battery pack in the battery pack is equivalent to the battery pack, the battery cell is equivalent to the module, or the battery pack is equivalent to the module, and the battery cell is equivalent to the battery cell; if the CTP (i.e., the two-level structure of the battery cell and the battery pack) power battery structure is used, then Figure 3 The battery pack is equivalent to the battery pack, and the battery unit is equivalent to the battery cell.

[0048] In this embodiment, Figure 3 The connecting lines in the drawings may only represent the positive electrode, and the negative electrode may be connected through a common ground line.

[0049] Reference Figure 3All battery cells in the battery pack in the automobile power supply system are connected in series, in parallel, or in a combination of series and parallel to obtain a first power supply terminal. Specifically, the voltage and current provided by the first power supply terminal need to meet the voltage and current requirements of the high-voltage load (such as the motor that drives the car). According to the principle that "series connection can increase voltage" and "parallel connection can increase current", all battery cells are connected together so that the obtained first power supply terminal meets the voltage and current requirements.

[0050] Reference Figure 3 , some battery cells in the battery pack in the automobile power supply system form the second power supply terminal. Specifically, the voltage and current provided by the second power supply terminal need to meet the voltage and current requirements of low-voltage loads (such as air conditioners and audio-visual entertainment systems, etc.). According to the principle that "series connection can increase voltage" and "parallel connection can increase current", the number and connection method of the battery cells involved in the connection are determined. If only one battery cell can meet the voltage and current requirements of the second power supply terminal, then the output end (positive and negative electrodes) of this battery cell can be used as the second power supply terminal. If multiple battery cells are required to meet the voltage and current requirements of the second power supply terminal, then these battery cells can be connected together so that the obtained second power supply terminal meets the voltage and current requirements.

[0051] In this embodiment, the voltage conversion unit is a DC-DC component, which has an input terminal and an output terminal. Figure 3 The input end of the voltage conversion unit is connected to the first power supply end, and the voltage conversion unit can perform DC-DC voltage conversion, reducing the high voltage (usually 300V or higher voltage level) provided by the first power supply end to a level suitable for the low-voltage load (usually 12V voltage level) for output.

[0052] In this embodiment, the output voltage of the output terminal of the voltage conversion unit and the output voltage of the second power supply terminal have the same voltage level, for example, both are 12V.

[0053] In this embodiment, refer to Figure 3 The power supply switching unit is provided with a first input terminal, a second input terminal and an output terminal. The first input terminal of the power supply switching unit is connected to the output terminal of the voltage conversion unit, the second input terminal of the power supply switching unit is connected to the second power supply terminal, and the output terminal of the power supply switching unit is connected to the low-voltage load of the vehicle.

[0054] In this embodiment, the power supply switching unit has a switch switching function, and a controllable switch component such as a relay or a field effect transistor can be used as the power supply switching unit.

[0055] Reference Figure 3, the output end of the power supply switching unit can be switched to be connected to the first input end or the second input end. That is to say, at the same time, the output end of the power supply switching unit is either connected to the first input end (not connected to the second input end) or connected to the second input end (not connected to the first input end).

[0056] Reference Figure 3 When the output end of the power supply switching unit is connected to the first input end (not connected to the second input end), the low-voltage load obtains power from the first power supply end of the battery pack; when the output end of the power supply switching unit is connected to the second input end (not connected to the first input end), the low-voltage load obtains power from the second power supply end of the battery pack.

[0057] In this embodiment, the automobile power supply system supplies power to the low-voltage load through the first power supply end formed by all the battery cells of the battery pack after passing through the voltage conversion unit, and can supply power to the low-voltage load through the second power supply end formed by some of the battery cells of the battery pack. The power supply switching unit selects the first power supply end or the second power supply end to supply power to the low-voltage load. On the one hand, it is unnecessary to set up a low-voltage battery, and only the battery pack as a power battery is set up to supply power to the low-voltage load, thereby reducing the use and maintenance costs; on the other hand, the first power supply end (powered by the entire battery pack) and the second power supply end (powered by part of the battery pack) can serve as a primary and a backup for each other, reducing the impact of partial damage to the battery pack on the power supply to the low-voltage load, thereby ensuring stable power supply to the low-voltage load.

[0058] In this embodiment, refer to Figure 4 The input end of the battery management system BMS in the automobile power supply system is connected to the first power supply end, and the output end of the battery management system is connected to the high-voltage load of the automobile. In this way, one battery pack can supply power to both the low-voltage load and the high-voltage load on the automobile, thereby improving the use efficiency of automobile components, eliminating the need to set up a low-voltage battery, and reducing the use and maintenance costs.

[0059] In this embodiment, when the power supply switching unit performs “switching the output end of the power supply switching unit to be connected to the first input end or the second input end”, the following steps may be specifically performed:

[0060] S301. Detecting the working state of the voltage conversion unit;

[0061] S302. When the voltage conversion unit is in normal working state, the output end of the power supply switching unit is switched to be connected to the first input end;

[0062] S303. When the working state of the voltage conversion unit is abnormal, the output end of the power supply switching unit is switched to be connected to the second input end.

[0063] In step S301, the working state of the voltage conversion unit can be detected by using the self-checking function of the voltage conversion unit. In this embodiment, the working state of the voltage conversion unit indicates whether the voltage conversion of the voltage conversion unit works normally.

[0064] If it is detected that the working state of the voltage conversion unit is normal, the power supply switching unit executes step S302 to switch the output end of the power supply switching unit to be connected to the first input end. Specifically, if the output end of the power supply switching unit is connected to the first input end, then this connection is maintained; if the output end of the power supply switching unit is connected to the second input end, then the output end of the power supply switching unit is disconnected from the second input end and switched to be connected to the first input end. By executing step S302, the low-voltage load of the car can be powered by the first power supply end of the battery pack.

[0065] If it is detected that the working state of the voltage conversion unit is abnormal, the power supply switching unit executes step S303 to switch the output end of the power supply switching unit to connect with the second input end. Specifically, if the output end of the power supply switching unit is connected to the second input end, then this connection is maintained; if the output end of the power supply switching unit is connected to the first input end, then the output end of the power supply switching unit is disconnected from the first input end and switched to connect with the second input end. By executing step S303, the low-voltage load of the car can be powered by the second power supply end of the battery pack.

[0066] By executing steps S301-S303, the first power supply end of the battery pack can be used as the main power supply end of the low-voltage load of the car, and the second power supply end of the battery pack can be used as the backup power supply end of the low-voltage load of the car.

[0067] In this embodiment, refer to Figure 5 , the automobile power supply system also includes a battery partitioning unit. The battery partitioning unit can partition the battery cells in the battery pack, and determine at least one of the battery cells as a target battery cell. The output end of the battery cell determined as the target battery cell will be connected to form a second power supply end, and the battery cell that is not determined as the target battery cell will not be connected to the second power supply end. Specifically, if the number of target battery cells is one, then the output end of the target battery cell itself serves as the second power supply end; if the number of target battery cells is multiple, then the output ends of these target battery cells are connected in series and / or in parallel as the second power supply end, so that the voltage and current of the second power supply end can meet the needs of the low-voltage load.

[0068] A controllable selection component can be used as a battery partition unit. Figure 5As shown, the battery partition unit is provided with a plurality of input terminals, and the output terminals of all battery cells can be connected to a corresponding input terminal in the battery partition unit, and the output terminal of the battery partition unit serves as the second power supply terminal. The battery partition unit can control which input terminal is connected to its output terminal, and the battery cell connected to the input terminal selected to be connected to its output terminal becomes the target battery cell. In this way, dynamic partitioning of the battery pack can be realized, that is, which battery cells can be dynamically selected as target battery cells to be connected to obtain the second power supply terminal.

[0069] For example, if the number of target battery cells is one, the battery partition unit can connect its output terminal to the input terminal connected to the target battery cell and disconnect its output terminal from other input terminals. The battery partition unit can switch the connection relationship between its output terminal and input terminal to achieve the switching of the target battery cell, that is, dynamic partitioning of the battery pack.

[0070] In this embodiment, when the battery partitioning unit executes “partitioning each battery cell in the battery pack and determining at least one target battery cell”, the following steps may be specifically performed:

[0071] S401. Divide into multiple time periods;

[0072] S402. For any time period, load balancing is performed on each battery unit corresponding to the time period, and a target battery unit corresponding to the time period is determined according to the result of load balancing.

[0073] In step S401, the battery partitioning unit may divide the automobile power supply system into multiple time periods such as T1, T2, T3, etc. These time periods may be of equal length, and the next time period begins immediately after each time period ends.

[0074] In step S402, for any time period, the battery partition unit performs load balancing on each battery cell in the battery pack, and determines the target battery cell corresponding to the time period according to the result of load balancing. For example, in time period T1, the battery partition unit performs load balancing on each battery cell in the battery pack, and determines the target battery cell corresponding to time period T1 according to the result of load balancing; after time period T1 ends, it enters time period T2, and the battery partition unit performs load balancing on each battery cell in the battery pack, and determines the target battery cell corresponding to time period T2 according to the result of load balancing; after time period T2 ends, it enters time period T3, and the battery partition unit performs load balancing on each battery cell in the battery pack, and determines the target battery cell corresponding to time period T3 according to the result of load balancing...

[0075] By executing steps S401-S402, the battery partitioning unit can achieve dynamic load balancing of each battery cell in the battery pack, thereby realizing dynamic switching of the target battery cell (for example, selecting the battery cell numbered 1 as the target battery cell in time period T2, and selecting the battery cell numbered 3 as the target battery cell in time period T3), so that the selection of the target battery cell can meet the load balancing target of each battery cell, which is beneficial to extending the overall service life of each battery cell.

[0076] In this embodiment, when executing step S402, that is, for any time period, load balancing is performed on each battery unit corresponding to the time period, and the target battery unit corresponding to the time period is determined according to the result of load balancing, the following steps may be specifically performed:

[0077] S40201A. Obtain the low-voltage load record information corresponding to each battery unit at the start time of the time period;

[0078] S40202A. Filter out at least one low-voltage load record information;

[0079] S40203A. Determine the battery cell corresponding to the filtered low-voltage load record information as the target battery cell.

[0080] Steps S40201A-S40203A are the first execution method of step S402.

[0081] In this embodiment, steps S40201A-S40203A are respectively executed in each time period T1, T2, T3, ..., and the time period T2 is taken as an example for description.

[0082] In step S40201A, the battery partition unit can detect the low-voltage load record information corresponding to each battery cell at the starting moment of the time period T2. The low-voltage load record information of a battery cell represents the load record of this battery cell discharging the low-voltage load of the car in the previous period of time. The low-voltage load record information can be data such as the total energy and total duration of the discharge of the low-voltage load. For any battery cell, the battery partition unit can call its own record to query the record of this battery cell discharging through the second power supply end, and call the voltage conversion unit to query the record of this battery cell discharging through the first power supply end, and add up the two records to obtain the low-voltage load record information of this battery cell.

[0083] In step S40202A, the battery partition unit selects one or more low-voltage load record information with the lowest value, and executes step S40203A to determine the battery cells corresponding to these lowest low-voltage load record information as target battery cells.

[0084] In this embodiment, by executing steps S40201A-S40203A, those battery cells with the lowest low-voltage load record information can be selected as target battery cells, so that the low-voltage load is powered by those battery cells with the lowest low-voltage load record information; since the low-voltage load record information is the lowest, the selected target battery cell has the least record of powering the low-voltage load in the past period of time, so executing steps S40201A-S40203A can achieve load balancing.

[0085] In this embodiment, when executing step S402, that is, for any time period, load balancing is performed on each battery unit corresponding to the time period, and the target battery unit corresponding to the time period is determined according to the result of load balancing, the following steps may be specifically performed:

[0086] S40201B. Obtaining high voltage load record information corresponding to each battery cell at the start time of the time period;

[0087] S40202B. Filter out at least one low-voltage load record information;

[0088] S40203B. Determine the battery cell corresponding to the filtered high-voltage load record information as the target battery cell.

[0089] Steps S40201B-S40203B are a second execution method of step S402.

[0090] In this embodiment, steps S40201B-S40203B are respectively executed in each time period T1, T2, T3, ..., and the time period T2 is taken as an example for description.

[0091] In step S40201B, the battery partition unit can detect the high-voltage load record information corresponding to each battery cell at the start time of time period T2. The high-voltage load record information of a battery cell represents the load record of this battery cell discharging the high-voltage load of the car in the previous period of time. The high-voltage load record information can be data such as the total energy and total duration of the discharge of the high-voltage load. For any battery cell, the battery partition unit can call the battery management system BMS to query the record of this battery cell discharging through the first power supply end to obtain the high-voltage load record information of this battery cell.

[0092] In step S40202B, the battery partition unit selects one or more high-voltage load record information with the lowest value, and executes step S40203B to determine the battery cells corresponding to these lowest high-voltage load record information as target battery cells.

[0093] In this embodiment, by executing steps S40201B-S40203B, those battery cells with the lowest high-voltage load record information can be selected as target battery cells, so that the low-voltage load is powered by those battery cells with the lowest high-voltage load record information; since the high-voltage load record information is the lowest, the selected target battery cell has the least record of powering the high-voltage load in the past period of time, and the high-voltage load of the battery cell generally accounts for a large proportion of its total load, so executing steps S40201B-S40203B can achieve load balancing.

[0094] In this embodiment, when executing step S402, that is, for any time period, load balancing is performed on each battery unit corresponding to the time period, and the target battery unit corresponding to the time period is determined according to the result of load balancing, the following steps may be specifically performed:

[0095] S40201C. Obtaining low-voltage load record information and high-voltage load record information corresponding to each battery unit at the start time of the time period;

[0096] S40202C. According to the low-voltage load record information and high-voltage load record information corresponding to the same battery cell, determine the total load record information corresponding to the same battery cell;

[0097] S40203C. Filter out at least one total load record information of the lowest;

[0098] S40204C. Determine the battery cell corresponding to the filtered total load record information as the target battery cell.

[0099] Steps S40201C-S40204C are the third execution method of step S402.

[0100] In this embodiment, steps S40201C-S40204C are respectively executed in each time period T1, T2, T3, ..., and the time period T2 is taken as an example for description.

[0101] Step S40201C is equivalent to the combination of step S40201A and step S40201B.

[0102] In step S40202C, for any battery cell, the corresponding low-voltage load record information and high-voltage load record information can be directly added together to obtain the total load record information corresponding to the battery cell. Corresponding weights can also be set for the low-voltage load record information and the high-voltage load record information, respectively, so as to perform weighted summation, and the obtained weighted sum is used as the total load record information corresponding to the battery cell.

[0103] In step S40202C, for any battery cell, the battery management system BMS can be called to detect the health information H and temperature information T of the battery cell at the starting moment of time period T2; the health information H represents the health of the battery cell (for example, it can be represented by data such as remaining service life), and the temperature information T represents the operating temperature of the battery cell due to charging and discharging or heat transfer from nearby battery cells.

[0104] In step S40202C, for any battery cell, the first weight w1 of the battery cell can be negatively correlated with the health information H of the battery cell, and the second weight w2 of the battery cell can be positively correlated with the temperature information T of the battery cell. That is, the larger the health information H of a battery cell, the larger the first weight w1, and the larger the temperature information T, the smaller the second weight w2. For example, positive coefficients k1 and k2 can be set, and the first weight w1 can be calculated by the formula w1=k1H, and the second weight w2 can be calculated by the formula Calculate the second weight w2.

[0105] In step S40202C, for any battery cell, its first weight w1 can be used as the weight corresponding to its low-voltage load record information, and its second weight w2 can be used as the weight corresponding to its high-voltage load record information. Alternatively, its first weight w1 can be used as the weight corresponding to its high-voltage load record information, and its second weight w2 can be used as the weight corresponding to its low-voltage load record information. For example, for any battery cell, the formula

[0106] Total load record information = w1 low-voltage load record information + w2 high-voltage load record information

[0107] or

[0108] Total load record information = w2 low-voltage load record information + w1 high-voltage load record information

[0109] The total load record information is calculated. In the above formula, the total load record information, the high voltage load record information, the low voltage load record information, the first weight w1 and the second weight w2 are all data corresponding to the same battery unit in the same time period.

[0110] In step S40203C, one or more battery cells with the lowest total load record information are screened out, and step S40204C is executed to determine the one or more battery cells with the lowest total load record information as the target battery cells.

[0111] In this embodiment, by executing steps S40201C-S40204C, those battery cells with the lowest total load record information can be selected as target battery cells, so that the low-voltage load is powered by those battery cells with the lowest total load record information; in the case where the total load record information is directly obtained by adding the high-voltage load record information and the low-voltage load record information, since the total load record information is the lowest, the selected target battery cell has the least record of powering the high-voltage load and the low-voltage load in the past period of time, so executing steps S40201C-S40204C can achieve load balancing; in the case where the total load record information is obtained by adding the high-voltage load record information When the weighted sum of the health information and the low-voltage load record information is obtained, since the weight is negatively correlated with the health information and positively correlated with the temperature information, executing steps S40201C-S40204C can give priority to selecting the battery cell with higher health information and lower temperature information as the target battery cell, and also supply power to the low-voltage load; since the target battery cell needs to supply power to both the high-voltage load and the low-voltage load, the consumption is relatively large, and steps S40201C-S40204C are usually executed, which can give priority to consuming the battery cells with higher health information and give priority to using the battery cells with lower temperature, which is conducive to achieving load balancing and ensuring safe use.

[0112] It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly fixed or connected to the other feature, or it may be indirectly fixed or connected to the other feature. In addition, the descriptions of up, down, left, right, etc. used in the present disclosure are only relative to the relative positional relationship of the components of the present disclosure in the accompanying drawings. The singular forms of "a", "" and "the" used in the present disclosure are also intended to include the plural forms, unless the context clearly indicates other meanings. In addition, unless otherwise defined, all technical and scientific terms used in this embodiment have the same meaning as those generally understood by those skilled in the art. The terms used in the specification of this embodiment are only for describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in this embodiment includes any combination of one or more related listed items.

[0113] It should be understood that, although the term first, second, third etc. may be adopted to describe various elements in the present disclosure, these elements should not be limited to these terms. These terms are only used to distinguish the same type of elements from each other. For example, without departing from the scope of the present disclosure, the first element may also be referred to as the second element, and similarly, the second element may also be referred to as the first element. The use of any and all examples or exemplary language ("for example", "such as" etc.) provided by the present embodiment is only intended to better illustrate embodiments of the present invention, and unless otherwise required, the scope of the present invention will not be limited.

[0114] It should be appreciated that embodiments of the present invention may be implemented or enforced by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable memory. The method may be implemented in a computer program using standard programming techniques - including a non-transitory computer-readable storage medium configured with a computer program, wherein the storage medium so configured causes the computer to operate in a specific and predefined manner - according to the methods and drawings described in the specific embodiments. Each program may be implemented in a high-level procedural or object-oriented programming language to communicate with a computer system. However, if desired, the program may be implemented in assembly or machine language. In any case, the language may be a compiled or interpreted language. In addition, the program may be run on a programmed dedicated integrated circuit for this purpose.

[0115] In addition, the operations of the process described in this embodiment may be performed in any suitable order, unless otherwise indicated in this embodiment or otherwise clearly contradicted by the context. The process described in this embodiment (or variations and / or combinations thereof) may be performed under the control of one or more computer systems configured with executable instructions, and may be implemented as a code (e.g., executable instructions, one or more computer programs, or one or more applications) executed on one or more processors in common, by hardware or a combination thereof. A computer program includes a plurality of instructions that may be executed by one or more processors.

[0116] Further, the method can be implemented in any type of computing platform that is operably connected to a suitable computer, including but not limited to a personal computer, a minicomputer, a mainframe, a workstation, a network or distributed computing environment, a separate or integrated computer platform, or in communication with a charged particle tool or other imaging device, etc. Various aspects of the present invention can be implemented in machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, an optical read and / or write storage medium, a RAM, a ROM, etc., so that it can be read by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the process described herein. In addition, the machine-readable code, or part thereof, can be transmitted via a wired or wireless network. When such media includes instructions or programs that implement the above steps in conjunction with a microprocessor or other data processor, the invention of this embodiment includes these and other different types of non-transitory computer-readable storage media. When programmed according to the methods and techniques of the present invention, the present invention also includes the computer itself.

[0117] The computer program can be applied to input data to perform the functions of the present embodiment, thereby converting the input data to generate output data stored in a non-volatile memory. The output information can also be applied to one or more output devices such as a display. In a preferred embodiment of the present invention, the converted data represents a physical and tangible object, including a specific visual depiction of the physical and tangible object produced on the display.

[0118] The above are only preferred embodiments of the present invention. The present invention is not limited to the above embodiments. As long as the technical effects of the present invention are achieved by the same means, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention. Within the scope of protection of the present invention, its technical solutions and / or implementation methods may have various modifications and changes.

Claims

1. An automobile power supply system, characterized in that: The automobile power supply system comprises: A battery pack; the battery pack comprises a plurality of battery cells, a first power supply end and a second power supply end; the first power supply end is formed by combining all the battery cells in series and / or in parallel, and the second power supply end is formed by a single battery cell, or by combining some of the battery cells in series and / or in parallel; A voltage conversion unit; the input end of the voltage conversion unit is connected to the first power supply end, and the voltage conversion unit is used to perform voltage conversion; A power supply switching unit; a first input end of the power supply switching unit is connected to the output end of the voltage conversion unit, a second input end of the power supply switching unit is connected to the second power supply end, and an output end of the power supply switching unit is used to connect to a low-voltage load of a car; the power supply switching unit is used to switch the output end of the power supply switching unit to be connected to the first input end or the second input end.

2. The automotive power supply system according to claim 1, characterized in that: The automobile power supply system further includes: Battery management system; the input end of the battery management system is connected to the first power supply end, and the output end of the battery management system is used to connect to the high-voltage load of the car.

3. The automotive power supply system according to claim 1, characterized in that: The step of switching the output end of the power supply switching unit to be connected to the first input end or the second input end includes: Detecting the working state of the voltage conversion unit; When the working state of the voltage conversion unit is normal, the output end of the power supply switching unit is switched to be connected to the first input end.

4. The automotive power supply system according to claim 3, characterized in that: The step of switching the output end of the power supply switching unit to be connected to the first input end or the second input end includes: When the working state of the voltage conversion unit is abnormal, the output end of the power supply switching unit is switched to be connected to the second input end.

5. The automotive power supply system according to any one of claims 1 to 4, characterized in that: The automobile power supply system further includes: A battery partitioning unit; the battery partitioning unit is used to partition each of the battery cells in the battery pack, determine at least one target battery cell, connect the output end of a single target battery cell as the second power supply end, or connect the output ends of multiple target battery cells in series and / or parallel as the second power supply end.

6. The automotive power supply system according to claim 5, characterized in that: Partitioning the battery cells in the battery pack to determine at least one target battery cell includes: Divide into multiple time periods; For any of the time periods, load balancing corresponding to the time period is performed on each of the battery units, and the target battery unit corresponding to the time period is determined according to the result of the load balancing.

7. The automotive power supply system according to claim 6, characterized in that: For any of the time periods, performing load balancing corresponding to the time period on each of the battery cells, and determining the target battery cell corresponding to the time period according to the result of the load balancing, includes: Obtaining low-voltage load record information corresponding to each of the battery units at the start time of the time period; the low-voltage load record information represents a load record of the battery unit discharging a low-voltage load of a vehicle; Filtering out at least one of the lowest low-voltage load record information; The battery cell corresponding to the filtered low-voltage load record information is determined as the target battery cell.

8. The automotive power supply system according to claim 6, characterized in that: For any of the time periods, performing load balancing corresponding to the time period on each of the battery cells, and determining the target battery cell corresponding to the time period according to the result of the load balancing, includes: Acquire high-voltage load record information corresponding to each of the battery units at the start time of the time period; the high-voltage load record information represents a load record of the battery unit discharging the high-voltage load of the vehicle; Filter out the lowest at least one of the high voltage load record information; The battery cell corresponding to the filtered high-voltage load record information is determined as the target battery cell.

9. The automotive power supply system according to claim 6, characterized in that: For any of the time periods, performing load balancing corresponding to the time period on each of the battery cells, and determining the target battery cell corresponding to the time period according to the result of the load balancing, includes: Obtaining low-voltage load record information and high-voltage load record information corresponding to each of the battery units at the start time of the time period; the low-voltage load record information represents a load record of the battery unit discharging the low-voltage load of the vehicle, and the high-voltage load record information represents a load record of the battery unit discharging the high-voltage load of the vehicle; Determine the total load record information corresponding to the same battery unit according to the low voltage load record information and the high voltage load record information corresponding to the same battery unit; Filter out at least one of the total load record information with the lowest value; The battery cell corresponding to the filtered total load record information is determined as the target battery cell.

10. The automotive power supply system according to claim 9, characterized in that: The determining the total load record information corresponding to the same battery unit according to the low-voltage load record information and the high-voltage load record information corresponding to the same battery unit includes: For any of the battery cells, obtaining health information and temperature information of the battery cell; Determine a first weight of the battery cell according to the health information; the first weight is negatively correlated with the health information; Determining a second weight of the battery cell according to the temperature information; the second weight is positively correlated with the temperature information; The low-voltage load record information and the high-voltage load record information are weighted and summed according to the first weight and the second weight to obtain the total load record information.

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