Control method and control system for preventing battery feedback overvoltage

Abstract

The invention relates to the technical field of power batteries, in particular to a control method and a control system for preventing battery feedback overvoltage. Comprising the following steps: acquiring a voltage dynamic change relation table of a target battery under different currents and different temperatures when the target battery is in an early warning electric quantity threshold value and an emergency electric quantity threshold value; obtaining a power change relation table of the power of the target battery under the two electric quantity threshold states at different temperatures; monitoring a real-time voltage value, real-time temperature information and real-time current information in the operation process of the target battery, and combining the two voltage dynamic change relation tables to obtain a corresponding early warning overvoltage threshold value and an emergency overvoltage threshold value; and comparing and judging the real-time voltage value with an early warning overvoltage threshold value and an emergency overvoltage threshold value, and correcting. The dynamic change table is pre-calibrated for the voltage threshold value corresponding to the early warning electric quantity, whether the voltage of the battery exceeds the threshold value or not is judged according to the real-time state of the battery during operation, the method is more accurate compared with simple SOC table look-up, and the method is more timely compared with the method of limiting when the voltage reaches the overvoltage threshold value point.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and in particular to a control method and control system for preventing battery feedback overvoltage. Background Art

[0002] With advances in new energy vehicle technology, battery cost-effectiveness has increased, but their output capacity is nearing its limits. To extend battery life, electric vehicles generate regenerative current / power to charge the battery during operation, especially during braking and downhill conditions, thereby increasing the vehicle's range. However, the allowable regenerative current / power varies depending on the battery's charge level. When the battery management system (BMS) indicates that the allowable regenerative current / power exceeds the battery's actual capacity, the battery is at risk of overcharging. This can damage the battery cell, affecting its charge and discharge capabilities and range; in severe cases, it can lead to battery failure or even serious safety issues such as fire. Therefore, it is crucial to prevent overcharging during battery use.

[0003] Related technologies primarily use SOC (State of Charge) and temperature to determine allowable power. However, the accuracy of SOC estimation is limited, which can cause the battery's feedback allowable power, as determined by the table, to be excessive. Once the battery's feedback allowable power exceeds its actual capacity, the battery voltage can rise sharply, triggering the overvoltage protection mechanism and significantly limiting battery power. In this case, the vehicle may experience power failure, or even safety issues such as power loss and vehicle forward movement. Summary of the Invention

[0004] In the related art, the limited accuracy of battery state of charge estimation leads to deviation in the battery feedback allowable power obtained by lookup table, which in turn triggers the overvoltage protection mechanism, resulting in a significant limitation of battery power.

[0005] In a first aspect, an embodiment of the present application provides a control method for preventing battery feedback overvoltage, characterized in that the feedback overvoltage control method includes: Obtain a voltage dynamic change relationship table at different currents and temperatures when the target battery is at the warning power threshold and the emergency power threshold respectively; Obtain a power variation relationship table of the target battery at two power threshold states and at different temperatures; Monitor the real-time voltage, temperature, and current of the target battery during operation, and combine the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold; Compare the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold, and determine whether to perform power correction on the target battery based on the comparison result; If the real-time voltage value does not exceed the warning overvoltage threshold, it is determined that the target battery does not need power correction; If the real-time voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, a correction value of the target battery is obtained according to the power change relationship table of the target battery under the warning power threshold; If the real-time voltage value exceeds the warning overvoltage threshold and the emergency overvoltage threshold at the same time, the correction value of the target battery is obtained according to the power change relationship table when the target battery is at the emergency power threshold.

[0006] In combination with the first aspect, in one embodiment, obtaining a table of dynamic voltage changes of a target battery cell at different currents and temperatures when the target battery is at a warning power threshold and an emergency power threshold, respectively, includes: Obtain the voltage change curve of the target battery at different temperatures and currents; According to the voltage change curve, all warning voltage parameters and emergency voltage parameters corresponding to the target battery being at the warning power threshold and the emergency power threshold are extracted respectively; According to the corresponding relationship between the warning voltage parameter and the emergency voltage parameter and the voltage change curve, a two-dimensional relationship table of the voltage dynamic changes of the two and the current and temperature is obtained.

[0007] In combination with the first aspect, in one implementation, the warning power threshold of the target battery is 95% of the full charge, and the emergency power threshold of the target battery is 97% of the full charge.

[0008] In combination with the first aspect, in one embodiment, monitoring the real-time voltage value, real-time temperature information, and real-time current information of the target battery during operation includes: monitoring the maximum temperature and the minimum temperature of the target battery during operation.

[0009] In conjunction with the first aspect, in one embodiment, combining the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold includes: The two warning voltages corresponding to the target battery's minimum and maximum temperatures and currents are obtained from the voltage dynamic change relationship table of the warning voltage preset values, and the minimum value of the two warning voltages is used as the warning overvoltage threshold; The two warning voltages of the target battery at the lowest temperature and the highest temperature are obtained through the voltage dynamic change relationship table of the warning power threshold, and the minimum value of the two warning voltages is used as the warning overvoltage threshold.

[0010] In combination with the first aspect, in one embodiment, obtaining the correction value of the target battery according to the power change relationship table corresponding to the preset warning voltage value includes: Obtain the real-time power value of the target battery at the current power level and temperature based on the real-time voltage value; The correction value of the target battery power is calculated according to the preset correction ratio and the real-time power value.

[0011] In combination with the first aspect, in one embodiment, calculating the correction value of the target battery power according to the preset correction ratio and the real-time power value includes: 50% of the standard power value is used as the target power value, and the difference between the target power value and the real-time power value is used as the correction value of the target battery power.

[0012] In combination with the first aspect, in one embodiment, after comparing the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold, the method further includes: The power of the target battery is corrected at a correction rate that is higher than a normal power change rate of the target battery.

[0013] In combination with the first aspect, in one embodiment, after comparing the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold, the method further includes: Monitor the health status parameters of the target battery and correct the power correction value of the target battery in real time according to changes in the health status parameters of the target battery.

[0014] In a second aspect, an embodiment of the present application provides a control system for preventing battery feedback overvoltage, comprising: A calibration module is used to obtain a table showing the dynamic voltage change relationship of the target battery at different currents and temperatures when the target battery is at the warning power threshold and the emergency power threshold. The calibration module is also used to obtain a table showing the power change relationship of the target battery at different temperatures when the target battery is at the two power thresholds. A monitoring module is used to monitor the real-time voltage, temperature, and current of the target battery during operation. The monitoring module is also used to combine the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold; The judgment module is used to compare the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold; wherein, If the real-time voltage value does not exceed the warning overvoltage threshold, it is determined that the target battery does not need power correction; If the real-time voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, the correction value of the target battery is obtained according to the power change relationship table corresponding to the warning voltage preset value; If the real-time voltage value exceeds both the warning overvoltage threshold and the emergency overvoltage threshold, the correction value of the target battery is obtained according to the power change relationship table corresponding to the emergency voltage preset value.

[0015] The beneficial effects of the technical solutions provided in the embodiments of the present application include: This application sets two warning power levels and pre-calibrates a dynamic change table for the voltage threshold corresponding to the warning power level. It then determines whether the battery voltage exceeds the threshold based on the real-time status of the battery during operation, and further determines whether the power needs to be adjusted to avoid excessive feedback current / power. This is more accurate than simply looking up the SOC table and more timely than limiting the voltage when it reaches the overvoltage threshold. Furthermore, this application sets two overvoltage thresholds to provide redundant voltage warning settings, better protecting battery feedback. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a flow chart of an embodiment of a control method for preventing battery feedback overvoltage in the present application; Figure 2 This is a schematic diagram of the hardware structure of a control device for preventing battery feedback overvoltage involved in an embodiment of the present application. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0018] In the related art, the limited accuracy of battery state of charge estimation leads to deviation in the battery feedback allowable power obtained by lookup table, which in turn triggers the overvoltage protection mechanism, resulting in a significant limitation of battery power.

[0019] In a first aspect, an embodiment of the present application provides a control method for preventing battery feedback overvoltage, the feedback overvoltage control method comprising the following steps: Step S1: Obtain a voltage dynamic change relationship table at different currents and different temperatures when the target battery is at a warning power threshold and an emergency power threshold.

[0020] The above step S1 includes: Step S1a: Obtain voltage variation curves of the target battery at different temperatures and currents.

[0021] Specifically, the battery cells used in the corresponding project are tested at different rates and temperatures, with reference temperatures of 0°C, 10°C, 25°C, and 45°C respectively; the reference currents are 0.1C, 0.3C, 0.5C, and 0.7C respectively, and charging tests are carried out. The charging process is to charge from the lowest value Vlow of the single cell voltage (lithium iron phosphate is generally 2.5V, which can be adjusted according to the specific battery cell) to the cut-off voltage Vfull (lithium iron phosphate is generally 3.65V, which can be adjusted according to the specific battery cell), and obtain the voltage change curve of the battery cell under different temperatures and different current rates.

[0022] Step S1b: extracting all warning voltage parameters and emergency voltage parameters corresponding to the warning power threshold and the emergency power threshold of the target battery according to the voltage change curve.

[0023] In some optional implementations, the warning power threshold and the emergency power threshold can be set to values ​​close to the target battery's near-full charge point (5% reserve) and near-full charge point (3% reserve). That is, the target battery's warning power threshold is 95% of the full charge, and the target battery's emergency power threshold is 97% of the full charge.

[0024] Specifically, all voltage parameters corresponding to the warning power threshold and the emergency power threshold in the voltage change curve are extracted and used as the warning voltage parameter and the emergency voltage parameter, respectively.

[0025] Step S1c: According to the corresponding relationship between the warning voltage parameter and the emergency voltage parameter and the voltage variation curve, a two-dimensional relationship table of the voltage dynamic variation of the warning voltage parameter and the emergency voltage parameter and the current and temperature is obtained.

[0026] Specifically, a two-dimensional table of voltage values ​​related to warning voltage parameters, current, and temperature is calibrated and prepared. Simultaneously, a two-dimensional table of voltage values ​​related to emergency voltage parameters, current, and temperature is calibrated and prepared. In subsequent steps, the corresponding warning voltage parameter or emergency voltage parameter can be queried using the linear difference between temperature and current.

[0027] Step S2: respectively obtain a power variation relationship table of the target battery at two power threshold states and at different temperatures.

[0028] It is worth noting that the table of state of charge (SOC) and temperature of the target battery is a conventional table for electric vehicles.

[0029] Step S3: monitoring the real-time voltage value, real-time temperature information, and real-time current information of the target battery during operation, and combining the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold; The above step S3 includes: Step S3a: measuring the real-time voltage value, real-time temperature information, and real-time current information of the target battery during operation.

[0030] Specifically, monitoring the real-time temperature information of the target battery during operation includes: obtaining the maximum temperature and the minimum temperature of the battery during operation.

[0031] Step S3b: Look up two voltage dynamic change relationship tables based on the current and maximum temperature, and the current and minimum temperature, respectively. This results in obtaining the warning overvoltage value and emergency overvoltage value corresponding to the maximum temperature, as well as the warning overvoltage value and emergency overvoltage value corresponding to the minimum temperature. The minimum of the two warning overvoltage values ​​is used as the warning overvoltage threshold, and the minimum of the two emergency overvoltage values ​​is used as the emergency overvoltage threshold.

[0032] It's worth noting that the warning overvoltage threshold and emergency overvoltage threshold obtained in the above steps are effective voltage thresholds close to the full charge point. Furthermore, since the warning overvoltage threshold corresponds to the warning battery threshold and the emergency overvoltage threshold corresponds to the emergency battery threshold, the warning overvoltage threshold is generally lower than the emergency overvoltage threshold.

[0033] Furthermore, the warning overvoltage threshold and the emergency overvoltage threshold need to be updated in real time according to the parameters monitored in real time in step S3a.

[0034] Step S4: Compare and judge the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold.

[0035] Specifically, the following are judged: Case 1: If the real-time voltage value does not exceed the warning overvoltage threshold, it is determined that the target battery does not need power correction.

[0036] It is understandable that when the highest voltage among the real-time voltage values ​​of the target battery does not exceed the warning overvoltage threshold, it indicates that power correction of the battery is not required.

[0037] Case 2: If the real-time voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, the correction value of the target battery is obtained according to the power change relationship table of the target battery under the warning power threshold.

[0038] Specifically, during vehicle operation, when the highest collected single cell voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, current / power reduction processing is directly performed.

[0039] Furthermore, reducing the current / power of the target battery includes: looking up the power change relationship table mentioned in step S2 to obtain the real-time power of the target battery under the current target battery power and temperature conditions, and calculating a correction value of the target battery power based on a preset correction ratio and the real-time power value.

[0040] Preferably, 50% of the real-time power value is used as the target power value, and the difference between the target power value and the real-time power value is used as the correction value of the target battery power.

[0041] It should be noted that the power reduction rate is 10 times the normal power change rate (calibrable), which is 10 times faster than the normal power reduction response speed.

[0042] Case 3: If the real-time voltage value exceeds the warning overvoltage threshold and the emergency overvoltage threshold at the same time, the correction value of the target battery is obtained according to the power change relationship table when the target battery is at the emergency power threshold.

[0043] Specifically, during vehicle operation, when the highest collected single cell voltage value exceeds the emergency overvoltage threshold, current / power reduction processing is directly performed.

[0044] Furthermore, reducing the current / power of the target battery includes: looking up the power change relationship table mentioned in step S2 to obtain the real-time power of the target battery under the current target battery power and temperature conditions, and calculating a correction value of the target battery power based on a preset correction ratio and the real-time power value.

[0045] Preferably, 20% of the real-time power value is used as the target power value, and the difference between the target power value and the real-time power value is used as the correction value of the target battery power.

[0046] It should be noted that the power reduction rate is 10 times the normal power change rate (calibrable), which is 10 times faster than the normal power reduction response speed.

[0047] Step S5: monitor the health status parameters of the target battery, and modify the power correction value of the target battery in real time according to changes in the health status parameters of the target battery.

[0048] It is worth noting that after the battery cell has been running for a long time, the battery SOH (State of Health) decreases, and the power reserve points corresponding to 5% and 3% close to full charge change, and the voltage value is compensated according to the laboratory data.

[0049] In some optional embodiments, the compensation value decreases by 1 mV for every 1% decrease in SOH.

[0050] In a second aspect, the present application provides a method for controlling a power battery, comprising: Step S1: Obtain a voltage dynamic change relationship table at different currents and different temperatures when the target battery is at a warning power threshold and an emergency power threshold.

[0051] The above step S1 includes: Step S1a: Obtain voltage variation curves of the target battery at different temperatures and currents.

[0052] Specifically, the battery cells used in the corresponding project are tested at different rates and temperatures, with reference temperatures of 0°C, 10°C, 25°C, and 45°C respectively; the reference currents are 0.1C, 0.3C, 0.5C, and 0.7C respectively, and charging tests are carried out. The charging process is to charge from the lowest value Vlow of the single cell voltage (lithium iron phosphate is generally 2.5V, which can be adjusted according to the specific battery cell) to the cut-off voltage Vfull (lithium iron phosphate is generally 3.65V, which can be adjusted according to the specific battery cell), and obtain the voltage change curve of the battery cell under different temperatures and different current rates.

[0053] Step S1b: extracting all warning voltage parameters and emergency voltage parameters corresponding to the warning power threshold and the emergency power threshold of the target battery according to the voltage change curve.

[0054] In some optional implementations, the warning power threshold and the emergency power threshold can be set to values ​​close to the target battery's near-full charge point (5% reserve) and near-full charge point (3% reserve). That is, the target battery's warning power threshold is 95% of the full charge, and the target battery's emergency power threshold is 97% of the full charge.

[0055] Specifically, all voltage parameters corresponding to the warning power threshold and the emergency power threshold in the voltage change curve are extracted and used as the warning voltage parameter and the emergency voltage parameter, respectively.

[0056] Step S1c: According to the corresponding relationship between the warning voltage parameter and the emergency voltage parameter and the voltage variation curve, a two-dimensional relationship table of the voltage dynamic variation of the warning voltage parameter and the emergency voltage parameter and the current and temperature is obtained.

[0057] Specifically, a two-dimensional table of voltage values ​​related to warning voltage parameters, current, and temperature is calibrated and prepared. Simultaneously, a two-dimensional table of voltage values ​​related to emergency voltage parameters, current, and temperature is calibrated and prepared. In subsequent steps, the corresponding warning voltage parameter or emergency voltage parameter can be queried using the linear difference between temperature and current.

[0058] Step S2: respectively obtain a power variation relationship table of the target battery at two power threshold states and at different temperatures.

[0059] It is worth noting that the table of state of charge (SOC) and temperature of the target battery is a conventional table for electric vehicles.

[0060] Step S3: monitoring the real-time voltage value, real-time temperature information, and real-time current information of the target battery during operation, and combining the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold; The above step S3 includes: Step S3a: measuring the real-time voltage value, real-time temperature information, and real-time current information of the target battery during operation.

[0061] Specifically, monitoring the real-time temperature information of the target battery during operation includes: obtaining the maximum temperature and the minimum temperature of the battery during operation.

[0062] Step S3b: Look up two voltage dynamic change relationship tables based on the current and maximum temperature, and the current and minimum temperature, respectively. This results in obtaining the warning overvoltage value and emergency overvoltage value corresponding to the maximum temperature, as well as the warning overvoltage value and emergency overvoltage value corresponding to the minimum temperature. The minimum of the two warning overvoltage values ​​is used as the warning overvoltage threshold, and the minimum of the two emergency overvoltage values ​​is used as the emergency overvoltage threshold.

[0063] It's worth noting that the warning overvoltage threshold and emergency overvoltage threshold obtained in the above steps are effective voltage thresholds close to the full charge point. Furthermore, since the warning overvoltage threshold corresponds to the warning battery threshold and the emergency overvoltage threshold corresponds to the emergency battery threshold, the warning overvoltage threshold is generally lower than the emergency overvoltage threshold.

[0064] Furthermore, the warning overvoltage threshold and the emergency overvoltage threshold need to be updated in real time according to the parameters monitored in real time in step S3a.

[0065] Step S4: Compare and judge the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold.

[0066] Specifically, the following are judged: Case 1: If the real-time voltage value does not exceed the warning overvoltage threshold, it is determined that the target battery does not need power correction.

[0067] It is understandable that when the highest voltage among the real-time voltage values ​​of the target battery does not exceed the warning overvoltage threshold, it indicates that power correction of the battery is not required.

[0068] Case 2: If the real-time voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, the correction value of the target battery is obtained according to the power change relationship table of the target battery under the warning power threshold.

[0069] Specifically, during vehicle operation, when the highest collected single cell voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, current / power reduction processing is directly performed.

[0070] Furthermore, reducing the current / power of the target battery includes: looking up the power change relationship table mentioned in step S2 to obtain the real-time power of the target battery under the current target battery power and temperature conditions, and calculating a correction value of the target battery power based on a preset correction ratio and the real-time power value.

[0071] Preferably, 50% of the real-time power value is used as the target power value, and the difference between the target power value and the real-time power value is used as the correction value of the target battery power.

[0072] It should be noted that the power reduction rate is 10 times the normal power change rate (calibrable), which is 10 times faster than the normal power reduction response speed.

[0073] Case 3: If the real-time voltage value exceeds the warning overvoltage threshold and the emergency overvoltage threshold at the same time, the correction value of the target battery is obtained according to the power change relationship table when the target battery is at the emergency power threshold.

[0074] Specifically, during vehicle operation, when the highest collected single cell voltage value exceeds the emergency overvoltage threshold, current / power reduction processing is directly performed.

[0075] Furthermore, reducing the current / power of the target battery includes: looking up the power change relationship table mentioned in step S2 to obtain the real-time power of the target battery under the current target battery power and temperature conditions, and calculating a correction value of the target battery power based on a preset correction ratio and the real-time power value.

[0076] Preferably, 50% of the real-time power value is used as the target power value, and the difference between the target power value and the real-time power value is used as the correction value of the target battery power.

[0077] It should be noted that the power reduction rate is 10 times the normal power change rate (calibrable), which is 10 times faster than the normal power reduction response speed.

[0078] Step S5: monitor the health status parameters of the target battery, and modify the power correction value of the target battery in real time according to changes in the health status parameters of the target battery.

[0079] It is worth noting that after the battery cell has been running for a long time, the battery SOH (State of Health) decreases, and the power reserve points corresponding to 5% and 3% close to full charge change, and the voltage value is compensated according to the laboratory data.

[0080] In some optional embodiments, the compensation value decreases by 1mV for every 1% decrease in SOH. In a third aspect, the present application provides a control system for preventing battery feedback overvoltage, comprising: A calibration module is used to obtain a table showing the dynamic voltage change relationship of the target battery at different currents and temperatures when the target battery is at the warning power threshold and the emergency power threshold. The calibration module is also used to obtain a table showing the power change relationship of the target battery at different temperatures when the target battery is at the two power thresholds. A monitoring module is used to monitor the real-time voltage, temperature, and current of the target battery during operation. The monitoring module is also used to combine the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold; The judgment module is used to compare the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold; wherein, If the real-time voltage value does not exceed the warning overvoltage threshold, it is determined that the target battery does not need power correction; If the real-time voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, the correction value of the target battery is obtained according to the power change relationship table corresponding to the warning voltage preset value; If the real-time voltage value exceeds both the warning overvoltage threshold and the emergency overvoltage threshold, the correction value of the target battery is obtained according to the power change relationship table corresponding to the emergency voltage preset value.

[0081] Among them, the functional implementation of each module in the above-mentioned control system for preventing battery feedback overvoltage corresponds to the various steps in the above-mentioned control method embodiment for preventing battery feedback overvoltage, and their functions and implementation processes are not repeated here one by one.

[0082] In a third aspect, an embodiment of the present application provides a control device for preventing battery feedback overvoltage. The control device for preventing battery feedback overvoltage may be a personal computer (PC), a laptop computer, a server, or other device with data processing capabilities.

[0083] Reference Figure 2 , Figure 2 Schematic diagram of the hardware structure of the control device for preventing battery feedback overvoltage in the embodiment of the present application. In the embodiment of the present application, the control device for preventing battery feedback overvoltage may include a processor, a memory, a communication interface, and a communication bus.

[0084] The communication bus may be of any type and is used to interconnect the processor, memory, and communication interface.

[0085] Communication interfaces include input / output (I / O) interfaces, physical interfaces, and logical interfaces. These interfaces interconnect components within the battery overvoltage protection control device, as well as interfaces that connect the battery overvoltage protection control device to other devices (such as other computing devices or user devices). Physical interfaces can include Ethernet, fiber optic, and ATM interfaces; user devices can include displays and keyboards.

[0086] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0087] The processor may be a general-purpose processor that can invoke a control program for preventing battery feedback overvoltage stored in a memory and execute the control method for preventing battery feedback overvoltage provided in the embodiments of the present application. For example, the general-purpose processor may be a central processing unit (CPU). The method executed when the control program for preventing battery feedback overvoltage is invoked can be referenced from the various embodiments of the control method for preventing battery feedback overvoltage provided in the present application and will not be further described here.

[0088] Those skilled in the art will understand that the hardware structure shown in Figure m does not constitute a limitation on the present application, and may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0089] In a fifth aspect, an embodiment of the present application also provides a computer-readable storage medium.

[0090] The computer-readable storage medium of the present application stores a control program for preventing battery feedback overvoltage, wherein when the control program for preventing battery feedback overvoltage is executed by a processor, the steps of the control method for preventing battery feedback overvoltage as described above are implemented.

[0091] The method implemented when the control program for preventing battery feedback overvoltage is executed can refer to the various embodiments of the control method for preventing battery feedback overvoltage in this application, and will not be described in detail here.

[0092] In summary, this application sets two warning power levels and pre-calibrates a dynamic change table for the voltage threshold corresponding to the warning power level. It then determines whether the battery voltage exceeds the threshold based on the real-time status of the battery during operation, and further determines whether the power needs to be adjusted to avoid excessive feedback current / power. This is more accurate than simply looking up the SOC table and more timely than limiting the voltage when it reaches the overvoltage threshold. Furthermore, this application sets two overvoltage thresholds, redundantly setting the voltage warning and better protecting the battery feedback.

[0093] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0094] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit the "first", "second" and "third" to different types.

[0095] In the description of the embodiments of this application, the words "exemplary," "for example," or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary," "for example," or "for example" in the embodiments of this application should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary," "for example," or "for example" is intended to present the relevant concepts in a concrete manner.

[0096] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0097] In some processes described in the embodiments of the present application, multiple operations or steps are included that appear in a specific order. However, it should be understood that these operations or steps may not be performed in the order in which they appear in the embodiments of the present application or may be performed in parallel. The sequence numbers of the operations are only used to distinguish between different operations, and the sequence numbers themselves do not represent any order of execution. In addition, these processes may include more or fewer operations, and these operations or steps may be performed in sequence or in parallel, and these operations or steps may be combined.

[0098] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, or the part that contributes to the existing technology, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above and includes a number of instructions for enabling a terminal device to execute the methods described in each embodiment of this application.

[0099] The above are only preferred embodiments of the present application and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A control method for preventing battery feedback overvoltage, characterized in that: The feedback overvoltage control method includes: Obtain a voltage dynamic change relationship table at different currents and temperatures when the target battery is at the warning power threshold and the emergency power threshold respectively; Obtain a power variation relationship table of the target battery at two power threshold states and at different temperatures; Monitor the real-time voltage, temperature, and current of the target battery during operation, and combine the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold; Compare the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold, and determine whether to perform power correction on the target battery based on the comparison result; If the real-time voltage value does not exceed the warning overvoltage threshold, it is determined that the target battery does not need power correction; If the real-time voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, a correction value of the target battery is obtained according to the power change relationship table of the target battery under the warning power threshold; If the real-time voltage value exceeds the warning overvoltage threshold and the emergency overvoltage threshold at the same time, the correction value of the target battery is obtained according to the power change relationship table when the target battery is at the emergency power threshold.

2. The control method for preventing battery feedback overvoltage according to claim 1, characterized in that: The table of dynamic voltage change relationships of the target battery cells at different currents and temperatures when the target battery is at the warning power threshold and the emergency power threshold is obtained, including: Obtain the voltage change curve of the target battery at different temperatures and currents; According to the voltage change curve, all warning voltage parameters and emergency voltage parameters corresponding to the target battery being at the warning power threshold and the emergency power threshold are extracted respectively; According to the corresponding relationship between the warning voltage parameter and the emergency voltage parameter and the voltage change curve, a two-dimensional relationship table of the voltage dynamic changes of the two and the current and temperature is obtained.

3. The control method for preventing battery feedback overvoltage according to claim 2, wherein: The warning power threshold of the target battery is 95% of the full charge, and the emergency power threshold of the target battery is 97% of the full charge.

4. The control method for preventing battery feedback overvoltage according to claim 1, wherein: The monitoring of the real-time voltage value, real-time temperature information and real-time current information of the target battery during operation includes: monitoring the maximum temperature and the minimum temperature of the target battery during operation.

5. The control method for preventing battery feedback overvoltage as claimed in claim 4, characterized in that: The method of combining the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold includes: The two warning voltages corresponding to the target battery's minimum and maximum temperatures and currents are obtained from the voltage dynamic change relationship table of the warning voltage preset values, and the minimum value of the two warning voltages is used as the warning overvoltage threshold; The two warning voltages of the target battery at the lowest temperature and the highest temperature are obtained through the voltage dynamic change relationship table of the warning power threshold, and the minimum value of the two warning voltages is used as the warning overvoltage threshold.

6. The control method for preventing battery feedback overvoltage according to claim 1, wherein: The step of obtaining the correction value of the target battery according to the power change relationship table corresponding to the preset warning voltage value includes: Obtain the real-time power value of the target battery at the current power level and temperature based on the real-time voltage value; The correction value of the target battery power is calculated according to the preset correction ratio and the real-time power value.

7. The control method for preventing battery feedback overvoltage according to claim 6, characterized in that: The step of calculating the correction value of the target battery power according to the preset correction ratio and the real-time power value includes: 50% of the standard power value is used as the target power value, and the difference between the target power value and the real-time power value is used as the correction value of the target battery power.

8. The control method for preventing battery feedback overvoltage as claimed in claim 1, characterized in that: After determining whether to perform power correction on the target battery according to the comparison result, the method further includes: The power of the target battery is corrected at a correction rate that is higher than a normal power change rate of the target battery.

9. The control method for preventing battery feedback overvoltage as claimed in claim 1, characterized in that: After comparing the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold, the method further includes: Monitor the health status parameters of the target battery and correct the power correction value of the target battery in real time according to changes in the health status parameters of the target battery.

10. A control system for preventing battery feedback overvoltage, characterized in that: include: A calibration module is used to obtain a table showing the dynamic voltage change relationship of the target battery at different currents and temperatures when the target battery is at the warning power threshold and the emergency power threshold. The calibration module is also used to obtain a table showing the power change relationship of the target battery at different temperatures when the target battery is at the two power thresholds. A monitoring module is used to monitor the real-time voltage, temperature, and current of the target battery during operation. The monitoring module is also used to combine the two voltage dynamic change relationship tables to obtain the corresponding warning overvoltage threshold and emergency overvoltage threshold; The judgment module is used to compare the real-time voltage value with the warning overvoltage threshold and the emergency overvoltage threshold; wherein, If the real-time voltage value does not exceed the warning overvoltage threshold, it is determined that the target battery does not need power correction; If the real-time voltage value exceeds the warning overvoltage threshold but does not exceed the emergency overvoltage threshold, the correction value of the target battery is obtained according to the power change relationship table corresponding to the warning voltage preset value; If the real-time voltage value exceeds both the warning overvoltage threshold and the emergency overvoltage threshold, the correction value of the target battery is obtained according to the power change relationship table corresponding to the emergency voltage preset value.

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