Control method, device, medium and system for battery pack of pure electric vehicle

Abstract

The present application provides a control method, device, medium and system for a battery pack of a pure electric vehicle. The method uses a first cell voltage and a current battery pack temperature to correct an initial battery continuous power limit value, or an initial battery peak power limit value, to obtain a corrected battery continuous power limit value, or a corrected battery peak power limit value, thereby reducing the output power limit value of the battery pack to smooth out changes in the output power of the battery pack. When the output power of the battery pack needs to be adjusted from a first target power to a second target power, the final output power limit value is determined based on the first target power and the second target power, thereby once again correcting the output power limit value of the battery pack, thereby further improving the effect of smoothing the speed change of the pure electric vehicle, thereby solving the problem of the existing solution in which the speed of the pure electric vehicle changes rapidly due to the excessively fast decrease rate of the battery output power.

Description

Technical Field

[0001] The present application relates to the technical field of pure electric vehicles, and in particular to a control method, device, medium and system for a battery pack of a pure electric vehicle. Background Art

[0002] In winter, battery temperature determines the battery's charge and discharge power. Battery manufacturers specify power limits for batteries at different temperatures and SOC ranges. As temperature and SOC decrease, depending on vehicle operating conditions, when the vehicle demands high current, the battery demands high power, causing a significant drop in battery voltage. Excessive voltage drops can trigger undervoltage power limits, causing a rapid drop in battery output power. Undervoltage can damage the battery and cause abrupt changes in vehicle power, resulting in jerks and impacting driver comfort.

[0003] The relationship between SOC and OCV (i.e. the open circuit voltage of the battery pack) is as follows Figure 1 shown.

[0004] That is, the pure electric vehicle of the existing solution has a problem that the speed of the pure electric vehicle changes rapidly due to the rapid decrease rate of the battery output power. Summary of the Invention

[0005] The main purpose of this application is to provide a control method, device, medium and system for a battery pack of a pure electric vehicle, so as to at least solve the problem of the existing solution that the pure electric vehicle has a rapid speed change due to the rapid decrease rate of battery output power.

[0006] To achieve the above objectives, according to one aspect of the present application, a method for controlling a battery pack of a pure electric vehicle is provided, the method comprising:

[0007] Obtaining a minimum cell voltage of a battery pack of a pure electric vehicle in a current acquisition cycle and a current temperature of the battery pack to obtain a first cell voltage and a current battery pack temperature;

[0008] When the first cell voltage is within a preset range, the initial battery continuous power limit value or the initial battery peak power limit value is corrected using the first cell voltage and the current battery pack temperature to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value;

[0009] In a case where the output power of the battery pack needs to be adjusted from a first target power to a second target power, determining a final output power limit value according to the first target power and the second target power, wherein when the first target power is the initial battery continuous power limit value, the second target power is the revised battery continuous power limit value, or when the first target power is the initial battery peak power limit value, the second target power is the revised battery peak power limit value;

[0010] The output power of the battery pack is adjusted from the first target power to a final output power limit to smooth the speed change of the pure electric vehicle.

[0011] Optionally, using the first cell voltage and the current battery pack temperature to correct the initial battery continuous power limit value or the initial battery peak power limit value to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value includes:

[0012] Performing anti-shake processing on the first cell voltage to obtain a second cell voltage, wherein the second cell voltage is the first cell voltage, or the second cell voltage is the minimum cell voltage of the battery pack in a previous acquisition cycle;

[0013] determining a target power correction coefficient as a preset power correction coefficient corresponding to the second cell voltage and the current battery pack temperature;

[0014] The corrected battery continuous power limit value is determined as the product of the initial battery continuous power limit value and the target power correction coefficient, or the corrected battery peak power limit value is determined as the product of the initial battery peak power limit value and the target power correction coefficient.

[0015] Optionally, determining a final output power limit according to the first target power and the second target power includes:

[0016] Acquire the output power of the battery pack at the current moment in real time to obtain the current output power;

[0017] performing an integration process on the first target power and the second target power to determine an integral calculation value;

[0018] Integrating the current output power and the second target power to determine an actual integral value;

[0019] The final output power limit is determined according to the integral calculation value, the integral actual value, the first target power, and the second target power.

[0020] Optionally, integrating the first target power and the second target power to determine an integral calculation value includes:

[0021] according to The integral calculation value is determined, wherein J1 is the integral calculation value, t is time, time1 is a preset time constant, P1 is the first target power, and P2 is the second target power.

[0022] Optionally, integrating the current output power and the second target power to determine an actual integral value includes:

[0023] according to Determine the actual value of the integral, where P s is the current output power, J2 is the actual integral value, P2 is the second target power, t is time, and time2 is the actual driving duration.

[0024] Optionally, adjusting the output power of the battery pack from the first target power to a final output power limit includes:

[0025] Adjust the output power of the battery pack from the first target power to the final output power limit, wherein the time required to adjust the output power of the battery pack from the first target power to the final output power limit is greater than or equal to the actual driving time.

[0026] Optionally, determining the final output power limit according to the integral calculated value, the integral actual value, the first target power, and the second target power includes:

[0027] according to Determine the final output power limit, where J2 is the actual value of the integral, P2 is the second target power, and P f is the final output power limit, J1 is the integral calculation value, and P1 is the first target power.

[0028] According to another aspect of the present application, a control device for a battery pack of a pure electric vehicle is provided, the device comprising:

[0029] an acquisition unit, configured to acquire a minimum cell voltage of a battery pack of a pure electric vehicle in a current acquisition cycle and a current temperature of the battery pack, to obtain a first cell voltage and a current battery pack temperature;

[0030] a first processing unit, configured to, when the first cell voltage is within a preset range, use the first cell voltage and a current battery pack temperature to correct an initial battery continuous power limit value or an initial battery peak power limit value to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value;

[0031] a second processing unit, configured to, when it is necessary to adjust the output power of the battery pack from a first target power to a second target power, determine a final output power limit value based on the first target power and the second target power, wherein when the first target power is the initial battery continuous power limit value, the second target power is the revised battery continuous power limit value, or when the first target power is the initial battery peak power limit value, the second target power is the revised battery peak power limit value;

[0032] The third processing unit is configured to adjust the output power of the battery pack from the first target power to a final output power limit value, so as to smooth the speed change of the pure electric vehicle.

[0033] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute any one of the methods described.

[0034] According to another aspect of the present application, a pure electric vehicle system is provided, which includes: a pure electric vehicle and a controller, wherein a battery pack of the pure electric vehicle communicates with the controller, and the controller is configured to execute any one of the methods described.

[0035] By applying the technical solution of the present application, when the first cell voltage is within a preset range, the initial battery continuous power limit value, or the initial battery peak power limit value, is corrected using the first cell voltage and the current battery pack temperature to obtain a corrected battery continuous power limit value, or a corrected battery peak power limit value, thereby reducing the limit value of the output power of the battery pack to smooth the change in the output power of the battery pack. When it is necessary to adjust the output power of the battery pack from the first target power to the second target power, the final output power limit value is determined based on the first target power and the second target power. Therefore, on the basis of reducing the limit value of the output power of the battery pack for the first time, the limit value of the output power of the battery pack is corrected again, thereby further improving the effect of smoothing the speed change of the pure electric vehicle, thereby solving the problem of the pure electric vehicle in the existing solution having a rapid speed change due to the excessively rapid decrease rate of the battery output power. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings that constitute part of this application are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0037] Figure 1 shows a schematic diagram of the SOC-OCV curve provided in the embodiments of the present application;

[0038] Figure 2 A schematic flow chart of a method for controlling a battery pack of a pure electric vehicle according to an embodiment of the present application is shown;

[0039] Figure 3 A schematic diagram showing parameter changes for determining a target power correction coefficient according to an embodiment of the present application is shown;

[0040] Figure 4 A schematic diagram showing a power change of a battery pack when determining an integral calculation value according to an embodiment of the present application is shown;

[0041] Figure 5 A schematic diagram showing the power change of a battery pack when determining an actual value of an integral according to an embodiment of the present application is shown;

[0042] Figure 6 A schematic flow chart of a method for controlling a battery pack of a pure electric vehicle according to an embodiment of the present application is shown;

[0043] Figure 7 A structural block diagram of a control device for a battery pack of a pure electric vehicle provided in accordance with an embodiment of the present application is shown. DETAILED DESCRIPTION

[0044] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0045] 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 drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0046] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations 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 necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0047] As introduced in the background technology, when pure electric vehicles are used in winter, the battery temperature determines the battery's charge and discharge power during winter operation. Battery manufacturers will provide battery power limits at different temperatures and SOC ranges. As the temperature decreases and the SOC drops, according to the vehicle's operating conditions, when the vehicle has a large current demand, the battery has a large power demand, and the battery voltage drops significantly. If the voltage drops too much, it will trigger the undervoltage power limit, and the battery output power will drop rapidly. If the voltage is low, it will cause certain damage to the battery and cause a sharp change in vehicle power, resulting in a setback. The driver's comfort when driving the vehicle will also be affected. In order to solve the problem of the existing pure electric vehicle having a rapid speed change due to the rapid drop rate of the battery output power, the embodiments of the present application provide a control method, device, medium and system for the battery pack of a pure electric vehicle.

[0048] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0049] Based on the characteristics of lithium iron phosphate batteries, a control method for a battery pack of a pure electric vehicle is provided in this embodiment. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0050] Figure 2 FIG. 1 is a flow chart of a method for controlling a battery pack of a pure electric vehicle according to an embodiment of the present application. Figure 2 As shown, the method includes the following steps:

[0051] Step S201, obtaining the minimum cell voltage of the battery pack of the pure electric vehicle in the current acquisition cycle and the current temperature of the battery pack, to obtain a first cell voltage and a current battery pack temperature;

[0052] Pure electric vehicles are light trucks.

[0053] Step S202 , when the first cell voltage is within a preset range, the initial battery continuous power limit value or the initial battery peak power limit value is corrected using the first cell voltage and the current battery pack temperature to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value;

[0054] Specifically, the preset range is the voltage interval (uCellMinY1, uCellMinY2) that calibrates the triggering of battery undervoltage. The initial battery continuous power limit value and the initial battery peak power limit value are obtained by looking up the table based on the battery cell temperature and SOC. For example, the initial battery continuous power limit value is 100W, which the battery pack can sustain for 30 seconds during operation, and the initial battery peak power limit value is 80W, which the battery pack can sustain for 40 seconds during operation. Then, within 30 seconds of operation, the maximum power of the battery pack can be continuously maintained at 100W, but cannot exceed 100W. Then, within 40 seconds of operation, the maximum power of the battery pack can be continuously maintained at 80W, but cannot exceed 100W. In other words, the duration of maintaining 100W output power cannot exceed 30 seconds, and the duration of maintaining 80W output power can exceed 30 seconds, but after exceeding 30 seconds, the maximum limit is 80W.

[0055] Step S202, i.e., using the first cell voltage and the current battery pack temperature to correct the initial battery continuous power limit value or the initial battery peak power limit value to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value, includes:

[0056] Performing anti-shake processing on the first cell voltage to obtain a second cell voltage, wherein the second cell voltage is the first cell voltage, or the second cell voltage is the minimum cell voltage of the battery pack in the previous acquisition cycle;

[0057] Specifically, in order to prevent the state of the minimum cell voltage from jumping when it is within the voltage range (uCellMinY1, uCellMinY2), anti-shake processing is added, such as Figure 3As shown, the first cell voltage is subjected to anti-shake processing to obtain the second cell voltage, and by setting a correction coefficient mapping relationship table (the correction coefficient mapping relationship table stores the mapping relationship between the second cell voltage, the current battery pack temperature and the preset power correction coefficient), the preset power correction coefficient corresponding to the above-mentioned second cell voltage and the above-mentioned current battery pack temperature is found, and the preset power correction coefficient is used as the above-mentioned target power correction coefficient. The anti-shake processing is characterized by calculating the absolute value of the difference between the minimum cell voltages of two adjacent acquisition cycles. If the absolute value of the difference is greater than or equal to the preset difference, the second cell voltage is determined to be the minimum value of the minimum cell voltages of the two acquisition cycles. Otherwise, the second cell voltage is determined to be the minimum cell voltage of the current acquisition cycle. The preset difference is taken according to the model of the battery pack.

[0058] Determining a target power correction coefficient as a preset power correction coefficient corresponding to the second cell voltage and the current battery pack temperature;

[0059] The corrected battery continuous power limit value is determined as the product of the initial battery continuous power limit value and the target power correction coefficient, or the corrected battery peak power limit value is determined as the product of the initial battery peak power limit value and the target power correction coefficient.

[0060] The preset power correction coefficient is less than 0.5. The power limit value of the battery pack is reduced by determining the above-mentioned corrected battery continuous power limit value as the product of the above-mentioned initial battery continuous power limit value and the above-mentioned target power correction coefficient, or by determining the above-mentioned corrected battery peak power limit value as the product of the above-mentioned initial battery peak power limit value and the above-mentioned target power correction coefficient, so as to smooth the change of the output power of the battery pack.

[0061] Step S203: When the output power of the battery pack needs to be adjusted from the first target power to the second target power, a final output power limit is determined based on the first target power and the second target power, wherein when the first target power is the initial battery continuous power limit, the second target power is the revised battery continuous power limit, or when the first target power is the initial battery peak power limit, the second target power is the revised battery peak power limit.

[0062] Step S203, i.e., determining a final output power limit according to the first target power and the second target power, includes:

[0063] Obtain the output power of the battery pack at the current moment in real time to obtain the current output power;

[0064] performing an integration process on the first target power and the second target power to determine an integral calculation value;

[0065] In one embodiment of the present application, integrating the first target power and the second target power to determine an integral calculation value includes:

[0066] according to Determine the above-mentioned integral calculation value, wherein J1 is the above-mentioned integral calculation value, t is time, time1 is a preset time constant, P1 is the above-mentioned first target power, and P2 is the above-mentioned second target power.

[0067] like Figure 4 As shown, the preset time constant can be 5S, 10S, or 30S. The preset time constant is determined according to the model of the battery pack. The first target power is 100W, the second target power is 50W, the time constant Time1 is 30s, and the current output power (ie, actual power) is 100W. At this time, the duration of the first target power is 30s, and the slow decline time from the first target power to the second target power is 30s.

[0068] Integrating the current output power and the second target power to determine an actual integral value;

[0069] Specifically, integrating the current output power and the second target power to determine an actual integral value includes:

[0070] according to Determine the actual value of the above integral, where P s is the current output power, J2 is the actual integral value, P2 is the second target power, t is time, and time2 is the actual driving duration.

[0071] like Figure 5 As shown, the actual driving duration is continuously increased until the actual integral value is greater than or equal to the calculated integral value. The actual driving duration at this time serves as the time required to adjust the output power of the battery pack from the first target power to the final output power limit, thereby further extending the output power adjustment duration of the battery pack compared to the existing solution. The first target power is 100W, the required power 2 is 50W, the time constant Time is 30s, and the actual power (i.e., the current output power) is 90W. At this time, the duration of the first target power is 37.5s, and the slow decline time from the first target power to the second target power is 37.5s.

[0072] The final output power limit is determined according to the integral calculation value, the integral actual value, the first target power, and the second target power.

[0073] The final power output change time is determined by the actual power. Compared with the step change with a fixed step size, it can output power more smoothly and stably.

[0074] Specifically, determining the final output power limit according to the integral calculation value, the integral actual value, the first target power, and the second target power includes:

[0075] according to Determine the final output power limit, where J2 is the actual value of the integral, P2 is the second target power, and P f is the above-mentioned final output power limit, J1 is the above-mentioned integral calculation value, and P1 is the above-mentioned first target power.

[0076] Specifically, the use of the above-mentioned final output power limit to limit the output power of the battery pack further improves the effect of smoothing the speed changes of the above-mentioned pure electric vehicle, thereby solving the problem of the existing solution of pure electric vehicles causing rapid speed changes due to the rapid decline rate of battery output power. The above-mentioned actual value of the integral is continuously increased until the actual value of the integral is greater than or equal to the above-mentioned calculated value of the integral. In order to prevent power jumps, a strategy based on time constant integration is introduced to ensure the smoothness of vehicle power switching and reduce the degradation of battery cell life.

[0077] A common method for maintaining smooth power switching is step-down. This method provides a single, stable power change step size and requires an appropriate step size. Larger step sizes result in less smooth power transitions, while smaller step sizes can lead to excessive power output and potentially cause cell undervoltage. A strategy based on time constant integration, however, maximizes final power output based on actual power changes, achieving maximum power without triggering cell undervoltage.

[0078] Step S204 : adjusting the output power of the battery pack from the first target power toward a final output power limit to smooth the speed change of the pure electric vehicle.

[0079] In the above steps, when the above-mentioned first cell voltage is within the preset range, the above-mentioned first cell voltage and the current battery pack temperature are used to correct the initial battery continuous power limit value, or the initial battery peak power limit value, to obtain a corrected battery continuous power limit value, or a corrected battery peak power limit value, thereby reducing the limit value of the output power of the battery pack to smooth the change in the output power of the battery pack. When it is necessary to adjust the output power of the above-mentioned battery pack from the first target power to the second target power, the final output power limit value is determined according to the above-mentioned first target power and the above-mentioned second target power, thereby correcting the limit value of the output power of the battery pack again on the basis of reducing the limit value of the output power of the battery pack for the first time, thereby further improving the effect of smoothing the speed change of the above-mentioned pure electric vehicle, thereby solving the problem of the pure electric vehicle in the existing solution having a fast speed change due to the excessively fast decrease rate of the battery output power.

[0080] The above steps consist of two strategies: the first is the terminal pre-undervoltage power control strategy, and the second is the power value switching strategy based on time constant integration.

[0081] The terminal pre-undervoltage power control strategy should be based on the battery characteristics in the low temperature and low SOC range, and calibrate the voltage range (uCellMinY1, uCellMinY2) that triggers the battery undervoltage, that is, the preset range. This range is determined by the battery SOC-OCV characteristics. For example, the characteristics of a lithium iron phosphate battery (such as Figure 1 The SOC-OCV curve shown in Figure 2 shows the voltage threshold that triggers battery discharge undervoltage. The voltage threshold is 2.8V (different batteries have different voltage values). The allowable operating voltage of the battery at 25°C is 2.5V (different batteries have different voltage values). The allowable operating voltage of the battery below 0°C is 2V (different batteries have different voltage values). The calibration of uCellMinY1 must be greater than or equal to the minimum value of the minimum cell voltage allowed to work; the calibration of uCellMinY2 must be greater than uCellMinY1 and not exceed the turning point of the platform area and the slope area. The actual application requires further calibration based on the vehicle configuration to determine the pre-undervoltage voltage range. The limit range is uCellMinY1 = the minimum value of the minimum cell voltage allowed to work, and uCellMinY2 = the turning point of the platform area and the slope area (determined by the battery specification).

[0082] Step S204, i.e., adjusting the output power of the battery pack from the first target power to the final output power limit, includes:

[0083] Adjust the output power of the battery pack from the first target power to the final output power limit, wherein the time required to adjust the output power of the battery pack from the first target power to the final output power limit is greater than or equal to the actual driving time.

[0084] Specifically, for example, if the actual driving time is 37 seconds, then the time required to adjust the output power of the battery pack from the first target power to the final output power limit is at least 37 seconds, and may be 38 seconds. This smoothes the change in battery power, and thus the change in vehicle speed, improving driver comfort.

[0085] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the implementation process of the control method for the battery pack of a pure electric vehicle of the present application will be described in detail below with reference to specific embodiments.

[0086] This embodiment relates to a specific control method for a battery pack of a pure electric vehicle, such as Figure 6 As shown, the following steps are included:

[0087] Obtaining the minimum cell voltage of the battery pack of the pure electric vehicle in the current collection cycle and the current temperature of the battery pack, and obtaining the first cell voltage and the current battery pack temperature;

[0088] When the first cell voltage is within a preset range, performing anti-shake processing on the first cell voltage to obtain a second cell voltage, wherein the second cell voltage is the first cell voltage, or the second cell voltage is the minimum cell voltage of the battery pack in the previous acquisition cycle;

[0089] Determining the target power correction coefficient as a preset power correction coefficient corresponding to the second cell voltage and the current battery pack temperature;

[0090] Determine the corrected battery continuous power limit value as the product of the initial battery continuous power limit value and the target power correction factor, or determine the corrected battery peak power limit value as the product of the initial battery peak power limit value and the target power correction factor;

[0091] When the output power of the battery pack needs to be adjusted from the first target power to the second target power, the output power of the battery pack at the current moment is acquired in real time to obtain the current output power;

[0092] Integrating the first target power and the second target power to determine an integral calculation value; integrating the current output power and the second target power to determine an integral actual value; and determining a final output power limit based on the integral calculation value, the integral actual value, the first target power, and the second target power, wherein the second target power is a revised battery continuous power limit when the first target power is an initial battery continuous power limit, or the second target power is a revised battery peak power limit when the first target power is an initial battery peak power limit;

[0093] The output power of the battery pack is adjusted from the first target power to the final output power limit to smooth the speed change of the pure electric vehicle.

[0094] When the above-mentioned first cell voltage is within the preset range, the initial battery continuous power limit value or the initial battery peak power limit value is corrected using the above-mentioned first cell voltage and the current battery pack temperature to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value, thereby reducing the limit value of the output power of the battery pack to smooth the change in the output power of the battery pack. When it is necessary to adjust the output power of the above-mentioned battery pack from the first target power to the second target power, the final output power limit value is determined based on the above-mentioned first target power and the above-mentioned second target power. Therefore, on the basis of reducing the limit value of the output power of the battery pack for the first time, the limit value of the output power of the battery pack is corrected again, thereby further improving the effect of smoothing the speed change of the above-mentioned pure electric vehicle, thereby solving the problem of the pure electric vehicle in the existing solution having a fast speed change due to the excessively fast decrease rate of the battery output power.

[0095] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0096] The embodiment of the present application also provides a control device for a battery pack of a pure electric vehicle. It should be noted that the control device for a battery pack of a pure electric vehicle in the embodiment of the present application can be used to execute the control method for a battery pack of a pure electric vehicle provided in the embodiment of the present application. The device is used to implement the above-mentioned embodiments and preferred implementation methods, and those that have been explained will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and conceived.

[0097] The following introduces the control device of the battery pack of a pure electric vehicle provided in an embodiment of the present application.

[0098] Figure 7 1 is a structural block diagram of a control device for a battery pack of a pure electric vehicle provided in accordance with an embodiment of the present application. Figure 7 As shown, the device includes:

[0099] An acquisition unit 71 is configured to acquire a minimum cell voltage of a battery pack of a pure electric vehicle in a current acquisition cycle and a current temperature of the battery pack, thereby obtaining a first cell voltage and a current battery pack temperature;

[0100] a first processing unit 72 configured to, when the first cell voltage is within a preset range, modify the initial battery continuous power limit value or the initial battery peak power limit value using the first cell voltage and the current battery pack temperature to obtain a modified battery continuous power limit value or a modified battery peak power limit value;

[0101] a second processing unit 73 configured to, when it is necessary to adjust the output power of the battery pack from the first target power to the second target power, determine a final output power limit value based on the first target power and the second target power value, wherein when the first target power is the initial battery continuous power limit value, the second target power is the revised battery continuous power limit value, or when the first target power is the initial battery peak power limit value, the second target power is the revised battery peak power limit value;

[0102] The third processing unit 74 is configured to adjust the output power of the battery pack from the first target power to a final output power limit value, so as to smooth the speed change of the pure electric vehicle.

[0103] In the above-mentioned device, when the above-mentioned first single cell voltage is within the preset range, the above-mentioned first single cell voltage and the current battery pack temperature are used to correct the initial battery continuous power limit value, or the initial battery peak power limit value, to obtain a corrected battery continuous power limit value, or a corrected battery peak power limit value, thereby reducing the limit value of the output power of the battery pack to smooth the change in the output power of the battery pack. When it is necessary to adjust the output power of the above-mentioned battery pack from the first target power to the second target power, the final output power limit value is determined according to the above-mentioned first target power and the above-mentioned second target power, thereby correcting the limit value of the output power of the battery pack again on the basis of lowering the limit value of the output power of the battery pack for the first time, thereby further improving the effect of smoothing the speed change of the above-mentioned pure electric vehicle, thereby solving the problem of the pure electric vehicle in the existing solution having a fast speed change due to the excessively fast decrease rate of the battery output power.

[0104] In one embodiment of the present application, the first processing unit includes a first processing unit, a first determining unit, and a second determining unit.

[0105] The first processing unit is configured to perform anti-shake processing on the first cell voltage to obtain a second cell voltage, wherein the second cell voltage is the first cell voltage, or the second cell voltage is the minimum cell voltage of the battery pack in a previous acquisition cycle;

[0106] The first determining unit is used to determine the target power correction coefficient as a preset power correction coefficient corresponding to the second cell voltage and the current battery pack temperature;

[0107] The second determining unit is used to determine the above-mentioned corrected battery continuous power limit value as the product of the above-mentioned initial battery continuous power limit value and the above-mentioned target power correction coefficient, or to determine the above-mentioned corrected battery peak power limit value as the product of the above-mentioned initial battery peak power limit value and the above-mentioned target power correction coefficient.

[0108] In one embodiment of the present application, the second processing unit includes an acquisition module, a third determination module, a fourth determination module, and a fifth determination module.

[0109] The acquisition module is used to obtain the output power of the battery pack at the current moment in real time to obtain the current output power;

[0110] The third determining module is used to perform an integration process on the first target power and the second target power to determine an integral calculation value;

[0111] The fourth determining module is used to integrate the current output power and the second target power to determine an actual integral value;

[0112] The fifth determining module is configured to determine the final output power limit value according to the integral calculation value, the integral actual value, the first target power, and the second target power.

[0113] In one embodiment of the present application, the third determination module includes a first determination submodule,

[0114] The first determining submodule is used to Determine the above-mentioned integral calculation value, wherein J1 is the above-mentioned integral calculation value, t is time, time1 is a preset time constant, P1 is the above-mentioned first target power, and P2 is the above-mentioned second target power.

[0115] In one embodiment of the present application, the fourth determination module includes a second determination submodule,

[0116] The second determining submodule is used to Determine the actual value of the above integral, where P s is the current output power, J2 is the actual integral value, P2 is the second target power, t is time, and time2 is the actual driving duration.

[0117] In one embodiment of the present application, the third processing unit includes a second processing module,

[0118] The second processing module is used to adjust the output power of the above-mentioned battery pack from the above-mentioned first target power to the above-mentioned final output power limit, wherein the time required to adjust the above-mentioned output power of the above-mentioned battery pack from the above-mentioned first target power to the above-mentioned final output power limit is greater than or equal to the above-mentioned actual driving time.

[0119] In one embodiment of the present application, the fifth determining module includes a third determining submodule,

[0120] The third determining submodule is used to determine the Determine the final output power limit, where J2 is the actual value of the integral, P2 is the second target power, and P f is the above-mentioned final output power limit, J1 is the above-mentioned integral calculation value, and P1 is the above-mentioned first target power.

[0121] The control device for the battery pack of the pure electric vehicle includes a processor and a memory. The acquisition unit, first processing unit, second processing unit, and third processing unit are all stored in the memory as program units. The processor executes the program units stored in the memory to implement the corresponding functions. The above modules are all located in the same processor; alternatively, the above modules can be located in different processors in any combination.

[0122] The processor includes a core, which retrieves the corresponding program unit from memory. One or more cores can be configured, and adjusting the core parameters can address the problem of rapid speed changes in pure electric vehicles caused by the rapid drop in battery output power in existing solutions.

[0123] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0124] An embodiment of the present invention provides a computer-readable storage medium, which includes a stored program, wherein when the program is running, the device where the computer-readable storage medium is located is controlled to execute the control method of the battery pack of the pure electric vehicle.

[0125] An embodiment of the present invention provides a processor, which is used to run a program, wherein the control method of the battery pack of the pure electric vehicle is executed when the program is run.

[0126] An embodiment of the present invention provides a device, comprising a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, the device performs at least the following steps: obtaining a minimum cell voltage of a battery pack of a pure electric vehicle in a current acquisition cycle and a current temperature of the battery pack to obtain a first cell voltage and a current battery pack temperature; when the first cell voltage is within a preset range, using the first cell voltage and the current battery pack temperature to correct an initial battery continuous power limit value or an initial battery peak power limit value to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value; when it is necessary to adjust the output power of the battery pack from a first target power to a second target power, determining a final output power limit value based on the first target power and the second target power, wherein when the first target power is the initial battery continuous power limit value, the second target power is the corrected battery continuous power limit value, or when the first target power is the initial battery peak power limit value, the second target power is the corrected battery peak power limit value; and adjusting the output power of the battery pack from the first target power to the final output power limit value to smooth vehicle speed changes of the pure electric vehicle. The devices in this article can be servers, PCs, PADs, mobile phones, etc.

[0127] The present application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program having at least the following method steps: obtaining the minimum cell voltage of a battery pack of a pure electric vehicle in a current acquisition cycle and the current temperature of the battery pack to obtain a first cell voltage and a current battery pack temperature; when the first cell voltage is within a preset range, using the first cell voltage and the current battery pack temperature to correct an initial battery continuous power limit value or an initial battery peak power limit value to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value; when it is necessary to adjust the output power of the battery pack from a first target power to a second target power, determining a final output power limit value based on the first target power and the second target power, wherein when the first target power is the initial battery continuous power limit value, the second target power is the corrected battery continuous power limit value, or when the first target power is the initial battery peak power limit value, the second target power is the corrected battery peak power limit value; and adjusting the output power of the battery pack from the first target power to the final output power limit value to smooth the speed change of the pure electric vehicle.

[0128] The present application also provides a pure electric vehicle system, comprising: a pure electric vehicle and a controller, wherein a battery pack of the pure electric vehicle communicates with the controller, and the controller is configured to execute any one of the above-described methods. When the first cell voltage is within a preset range, an initial battery continuous power limit value or an initial battery peak power limit value is corrected using the first cell voltage and the current battery pack temperature to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value, thereby reducing the output power limit value of the battery pack to smooth changes in the output power of the battery pack. When the output power of the battery pack needs to be adjusted from a first target power to a second target power, a final output power limit value is determined based on the first target power and the second target power. Thus, based on the initial reduction in the output power limit value of the battery pack, the output power limit value of the battery pack is further corrected, thereby further improving the effect of smoothing changes in the speed of the pure electric vehicle, thereby resolving the problem in existing solutions of pure electric vehicles where the speed of the pure electric vehicle changes rapidly due to an excessively rapid decrease in the battery output power.

[0129] Obviously, those skilled in the art will appreciate that the various modules or steps of the present invention described above can be implemented using a general-purpose computing device, can be centralized on a single computing device, or can be distributed across a network of multiple computing devices. They can be implemented using program code executable by the computing device, and thus, can be stored in a storage device and executed by the computing device. In some cases, the steps shown or described herein can be performed in a different order than that shown, or can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0130] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0131] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0132] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0133] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0134] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0135] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0136] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory media such as modulated data signals and carrier waves.

[0137] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0138] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0139] 1) The control method of the battery pack of the pure electric vehicle of the present application, when the above-mentioned first cell voltage is within the preset range, uses the above-mentioned first cell voltage and the current battery pack temperature to correct the initial battery continuous power limit value, or the initial battery peak power limit value, to obtain the corrected battery continuous power limit value, or the corrected battery peak power limit value, thereby reducing the limit value of the output power of the battery pack to smooth the change of the output power of the battery pack. When the output power of the above-mentioned battery pack needs to be adjusted from the first target power to the second target power, the final output power limit value is determined according to the above-mentioned first target power and the above-mentioned second target power, thereby correcting the limit value of the output power of the battery pack again on the basis of reducing the limit value of the output power of the battery pack for the first time, thereby further improving the effect of smoothing the speed change of the above-mentioned pure electric vehicle, thereby solving the problem of the pure electric vehicle of the existing solution having a fast speed change due to the excessively fast decrease rate of the battery output power.

[0140] 2) The control device of the battery pack of the pure electric vehicle of the present application, when the above-mentioned first cell voltage is within the preset range, uses the above-mentioned first cell voltage and the current battery pack temperature to correct the initial battery continuous power limit value, or the initial battery peak power limit value, to obtain the corrected battery continuous power limit value, or the corrected battery peak power limit value, thereby reducing the limit value of the output power of the battery pack to smooth the change of the output power of the battery pack. When the output power of the above-mentioned battery pack needs to be adjusted from the first target power to the second target power, the final output power limit value is determined according to the above-mentioned first target power and the above-mentioned second target power, thereby correcting the limit value of the output power of the battery pack again on the basis of reducing the limit value of the output power of the battery pack for the first time, thereby further improving the effect of smoothing the speed change of the above-mentioned pure electric vehicle, thereby solving the problem of the pure electric vehicle of the existing solution having a fast speed change due to the excessively fast decrease rate of the battery output power.

[0141] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A control method for a battery pack of a pure electric vehicle, characterized in that: include: Obtaining a minimum cell voltage of a battery pack of a pure electric vehicle in a current acquisition cycle and a current temperature of the battery pack to obtain a first cell voltage and a current battery pack temperature; When the first cell voltage is within a preset range, the initial battery continuous power limit value or the initial battery peak power limit value is corrected using the first cell voltage and the current battery pack temperature to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value; In a case where the output power of the battery pack needs to be adjusted from a first target power to a second target power, determining a final output power limit value according to the first target power and the second target power, wherein when the first target power is the initial battery continuous power limit value, the second target power is the revised battery continuous power limit value, or when the first target power is the initial battery peak power limit value, the second target power is the revised battery peak power limit value; adjusting the output power of the battery pack from the first target power toward a final output power limit to smooth a speed change of the pure electric vehicle; The initial battery continuous power limit value or the initial battery peak power limit value is corrected using the first cell voltage and the current battery pack temperature to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value, including: performing anti-shake processing on the first cell voltage to obtain a second cell voltage, wherein the second cell voltage is the first cell voltage, or the second cell voltage is the minimum cell voltage of the battery pack in the previous acquisition cycle; determining a target power correction coefficient as a preset power correction coefficient corresponding to the second cell voltage and the current battery pack temperature; determining the corrected battery continuous power limit value as the product of the initial battery continuous power limit value and the target power correction coefficient, or determining the corrected battery peak power limit value as the product of the initial battery peak power limit value and the target power correction coefficient.

2. The method according to claim 1, characterized in that Determining a final output power limit according to the first target power and the second target power includes: Acquire the output power of the battery pack at the current moment in real time to obtain the current output power; performing an integration process on the first target power and the second target power to determine an integral calculation value; Integrating the current output power and the second target power to determine an actual integral value; The final output power limit is determined according to the integral calculation value, the integral actual value, the first target power, and the second target power.

3. The method according to claim 2, characterized in that Integrating the first target power and the second target power to determine an integral calculation value includes: according to , determine the integral calculation value, where, is the integral calculation value, t is time, time1 is the preset time constant, is the first target power, is the second target power.

4. The method according to claim 2, characterized in that Integrating the current output power and the second target power to determine an actual integral value includes: according to , determine the actual value of the integral, where, is the current output power, is the actual value of the integral, is the second target power, t is time, and time2 is the actual driving duration.

5. The method according to claim 4, characterized in that Adjusting the output power of the battery pack from the first target power to a final output power limit includes: Adjust the output power of the battery pack from the first target power to the final output power limit, wherein the time required to adjust the output power of the battery pack from the first target power to the final output power limit is greater than or equal to the actual driving time.

6. The method according to claim 2, characterized in that Determining the final output power limit according to the integral calculation value, the integral actual value, the first target power, and the second target power includes: according to , determine the final output power limit, where, is the actual value of the integral, is the second target power, is the final output power limit, is the integral calculation value, is the first target power.

7. A control device for a battery pack of a pure electric vehicle, characterized in that: include: an acquisition unit, configured to acquire a minimum cell voltage of a battery pack of a pure electric vehicle in a current acquisition cycle and a current temperature of the battery pack, to obtain a first cell voltage and a current battery pack temperature; a first processing unit, configured to, when the first cell voltage is within a preset range, use the first cell voltage and a current battery pack temperature to correct an initial battery continuous power limit value or an initial battery peak power limit value to obtain a corrected battery continuous power limit value or a corrected battery peak power limit value; a second processing unit, configured to, when it is necessary to adjust the output power of the battery pack from a first target power to a second target power, determine a final output power limit value based on the first target power and the second target power, wherein when the first target power is the initial battery continuous power limit value, the second target power is the revised battery continuous power limit value, or when the first target power is the initial battery peak power limit value, the second target power is the revised battery peak power limit value; a third processing unit, configured to adjust the output power of the battery pack from the first target power to a final output power limit to smooth a speed change of the pure electric vehicle; The first processing unit includes a first processing unit, a first determining unit and a second determining unit, the first processing unit being used to perform anti-shake processing on the first cell voltage to obtain a second cell voltage, wherein the second cell voltage is the first cell voltage, or the second cell voltage is the minimum cell voltage of the battery pack in the previous acquisition cycle; the first determining unit being used to determine the target power correction coefficient as a preset power correction coefficient corresponding to the second cell voltage and the current battery pack temperature; the second determining unit being used to determine the corrected battery continuous power limit value as the product of the initial battery continuous power limit value and the target power correction coefficient, or determining the corrected battery peak power limit value as the product of the initial battery peak power limit value and the target power correction coefficient.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 6.

9. A pure electric vehicle system, characterized in that: include: A pure electric vehicle and a controller, wherein a battery pack of the pure electric vehicle communicates with the controller, and the controller is used to execute the method according to any one of claims 1 to 6.

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