Electric vehicle power battery discharge control method, computer device and storage medium

Abstract

The invention discloses a discharge control method for a power battery of an electric vehicle, a computer device and a storage medium, and the method can achieve the discharge control of the power battery according to a dynamically determined discharge cut-off execution value, can enable the charge state of the power battery to be maintained at a level which just meets the requirement of reaching a target charging pile. According to the method, the situation that control over the power battery is too conservative and use of other electric parts on the electric vehicle is affected can be avoided, and the situation that the power battery is over-discharged due to too aggressive control over the power battery or the electric vehicle cannot be driven to the position where the target charging pile is located due to the fact that the state of charge reserved in the power battery is low can also be avoided; according to the electric vehicle power battery discharge control method in the embodiment, the use flexibility of the electric vehicle can be improved, and the endurance anxiety of a user can be relieved or eliminated. The invention is widely applied to the technical field of automobiles.

Description

Technical Field

[0001] The present invention relates to the field of automobile technology, and in particular to a method for controlling the discharge of a power battery of an electric vehicle, a computer device and a storage medium. Background Art

[0002] The power battery of an electric vehicle supplies power for the driving and functional use of the electric vehicle. Since over-discharging of the power battery may cause damage to the structure of the power battery, and based on the fact that when the power battery is too low to drive the electric vehicle over a long distance, a certain amount of power must be retained to provide support for operations such as rescue, electric vehicles are generally not allowed to discharge the power battery completely. Specifically, a discharge cutoff value (for example, 5%) can be set in the battery management system of the electric vehicle. When the battery management system detects that the state of charge (SOC) of the power battery is lower than the discharge cutoff value, the power battery is normally controlled to stop discharging.

[0003] The size of the discharge cutoff value is actually the minimum value of the state of charge that the power battery retains when it stops discharging under normal circumstances. If the discharge cutoff value is too large, the control of the power battery is too conservative, and the power battery may stop discharging when it still has a large state of charge, causing the actual capacity of the power battery to decrease, affecting the use of electrical components such as the audio and video entertainment system, on-board cooking system, and external power supply system on the electric vehicle; if the discharge cutoff value is too small, the control of the power battery is too aggressive, which can easily cause over-discharge of the power battery and damage the power battery, and on the other hand, cause the state of charge retained in the power battery to be low, and the endurance of the electric vehicle will be reduced, making it difficult for users to drive to the destination as planned or seek help and rescue.

[0004] In the current related technologies, the setting of the discharge cut-off value is not flexible enough, and it is usually difficult to set a suitable discharge cut-off value, resulting in poor performance of the power battery, which can easily cause electric vehicle users to have range anxiety and other bad usage experiences. Summary of the invention

[0005] In view of the technical problems that the current automobile technology has the problem of insufficient flexibility in setting the discharge cutoff value, resulting in poor performance of the power battery, which easily causes electric vehicle users to have range anxiety and other bad usage experiences, the purpose of the present invention is to provide an electric vehicle power battery discharge control method, a computer device and a storage medium.

[0006] In one aspect, an embodiment of the present invention includes a method for controlling the discharge of a power battery of an electric vehicle, the method comprising the following steps:

[0007] Select at least one target charging pile;

[0008] Determine the discharge cut-off calculation value according to the charging pile position corresponding to the target charging pile;

[0009] When the discharge cutoff calculation value is valid, the discharge cutoff execution value is determined according to the discharge cutoff calculation value; the discharge cutoff execution value represents the minimum value of the state of charge that needs to be retained when the power battery is discharged;

[0010] According to the discharge cut-off execution value, discharge control is performed on the power battery of the electric vehicle.

[0011] Further, according to the charging pile position corresponding to the target charging pile, the discharge cut-off calculation value is determined, including:

[0012] Get the current position of the vehicle;

[0013] Get the vehicle battery information;

[0014] Route planning is performed based on the current location of the vehicle and the location of the charging pile to obtain the expected driving route;

[0015] Determine the environmental information along the route according to the expected driving route; the environmental information along the route refers to the information about the environment of the location through which the expected driving route passes;

[0016] When the environmental information along the way can be determined, the discharge cut-off calculation value is determined according to the environmental information along the way and the battery information of the vehicle, and the discharge cut-off calculation value is determined to be valid.

[0017] Further, according to the charging pile position corresponding to the target charging pile, the discharge cut-off calculation value is determined, including:

[0018] When the environmental information along the route cannot be determined, the discharge cutoff calculation value is determined to be invalid.

[0019] Furthermore, the battery information of the vehicle is obtained, including:

[0020] Obtain the total battery capacity, initial state of charge, temperature coefficient and redundancy coefficient of the power battery;

[0021] The total battery capacity, initial state of charge, temperature coefficient and redundancy coefficient are used as the battery information of the vehicle;

[0022] Determine the environmental information along the route based on the expected driving route, including:

[0023] According to the expected driving route, query the driving distance, ambient temperature and average driving power consumption;

[0024] The driving distance, ambient temperature and average driving power consumption are used as the environmental information along the way.

[0025] Furthermore, the discharge cut-off calculation value is determined according to the environmental information along the way and the battery information of the vehicle, including:

[0026] According to the formula

[0027] E required =D×C avg ×(1+k T ×T)

[0028]

[0029] SOC cut-off-compute =SOC theoretical ×(1+c 冗余 )

[0030] Perform calculations to determine the discharge cutoff calculation value; where SOC cut-off-compute is the discharge cut-off calculation value, D is the driving distance, T is the ambient temperature, C avg is the average driving power consumption, k T is the temperature coefficient, c 冗余 is the redundancy coefficient, B cap is the total battery capacity, SOC initial is the initial charge state.

[0031] Furthermore, the electric vehicle power battery discharge control method further includes:

[0032] When the discharge cutoff calculated value is invalid, obtain the discharge cutoff default value;

[0033] Detect the current state of charge of the power battery;

[0034] Detect the discharge cut-off setting value set by the user;

[0035] When the discharge cutoff setting value is detected, the relative size of the discharge cutoff setting value is determined;

[0036] When the discharge cutoff setting value is within the range of the allowable interval, the discharge cutoff setting value is determined as the discharge cutoff execution value; the upper limit of the allowable interval is the current state of charge, and the lower limit is the discharge cutoff default value;

[0037] When the discharge cutoff setting value is not detected, or the discharge cutoff setting value is outside the allowable range, the discharge cutoff default value is determined as the discharge cutoff execution value.

[0038] Further, according to the discharge cut-off execution value, the discharge control is performed on the power battery of the electric vehicle, including:

[0039] When a target charging pile is selected, discharge control is performed on the power battery of the electric vehicle according to the discharge cut-off execution value corresponding to the target charging pile;

[0040] When multiple target charging piles are selected, the discharge cutoff calculation value corresponding to each target charging pile is obtained, and the discharge cutoff calculation value is fitted according to the position of each charging pile to obtain a discharge cutoff curve;

[0041] According to the discharge cut-off curve, a discharge cut-off execution value is determined to perform discharge control on the power battery of the electric vehicle.

[0042] Further, according to the discharge cut-off curve, a discharge cut-off execution value is determined to perform discharge control on the power battery of the electric vehicle, including:

[0043] Obtain the linearity of each point on the discharge cut-off curve;

[0044] Determine the curve segment with the maximum linearity corresponding to the discharge cut-off curve;

[0045] A corresponding discharge cutoff calculation value is determined on the curve segment and used as a discharge cutoff execution value to execute discharge control on the power battery of the electric vehicle.

[0046] On the other hand, an embodiment of the present invention also includes a computer device, including a memory and a processor, the memory is used to store at least one program, and the processor is used to load at least one program to execute the electric vehicle power battery discharge control method in the embodiment.

[0047] On the other hand, an embodiment of the present invention further includes a computer-readable storage medium, in which a program executable by a processor is stored. When the program executable by the processor is executed by the processor, it is used to execute the electric vehicle power battery discharge control method in the embodiment.

[0048] The beneficial effects of the present invention are as follows: the electric vehicle power battery discharge control method in the embodiment can control the discharge of the power battery according to the dynamically determined discharge cut-off execution value, and can maintain the state of charge of the power battery at a level just sufficient to reach the target charging pile, and can avoid overly conservative control of the power battery affecting the use of other electrical components on the electric vehicle, and can also avoid overly aggressive control of the power battery causing over-discharge of the power battery, or causing the state of charge retained in the power battery to be low and unable to support the electric vehicle to drive to the location of the target charging pile; the electric vehicle power battery discharge control method in the embodiment can improve the use flexibility of the electric vehicle, and is conducive to reducing or eliminating the user's range anxiety. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 A schematic diagram of the structure of a vehicle system to which the electric vehicle power battery discharge control method can be applied in an embodiment;

[0050] Figure 2A schematic diagram of the steps of the electric vehicle power battery discharge control method in an embodiment;

[0051] Figure 3 A schematic diagram of a process for obtaining a vehicle function usage task in an embodiment;

[0052] Figure 4 A schematic diagram of the location distribution of multiple target charging piles in an embodiment;

[0053] Figure 5 A schematic diagram of coordinate points corresponding to each target charging pile in the embodiment;

[0054] Figure 6 A schematic diagram of a discharge cut-off curve obtained by fitting in the embodiment;

[0055] Figure 7 A schematic diagram of dynamically releasing power and dynamically retaining power in an embodiment;

[0056] Figure 8 Schematic diagram of the curve segment with the highest linearity in the discharge cut-off curve in the embodiment. DETAILED DESCRIPTION

[0057] In this embodiment, the electric vehicle power battery discharge control method can be applied to Figure 1 In the vehicle system shown. Figure 1 The vehicle system includes a control module, a navigation module, a communication module, a battery management system and a power battery.

[0058] In this embodiment, the control module is a component with data processing and control capabilities; the navigation module can detect the position of the vehicle by receiving satellite positioning signals, and can also calculate information such as the vehicle speed based on the detected position, as well as receive setting information such as the departure point and destination, perform route planning and generate navigation information, and the navigation module can run an electronic map application for positioning and navigation; the communication module has a wireless communication function and can connect to the Internet for communication; the power battery can be a lithium battery, which can discharge to provide power to power units such as the motor of the electric vehicle, as well as units such as the audio and video entertainment system; the battery management system (Battery Management System, BMS) manages the charging and discharging and health of the power battery.

[0059] In this embodiment, each step in the electric vehicle power battery discharge control method can be executed by the control module. The control module can call Figure 1 The various modules in the control module are used to obtain the information required to execute the electric vehicle power battery discharge control method, or to execute corresponding steps.

[0060] In this embodiment, the "vehicle" mentioned refers to the vehicle installed Figure 1 The vehicle of the vehicle system shown is a vehicle that executes the electric vehicle power battery discharge control method. The vehicle can be an electric vehicle, specifically a pure electric vehicle or a hybrid electric vehicle. In this embodiment, a pure electric vehicle is used as an example for description.

[0061] Reference Figure 2 , the electric vehicle power battery discharge control method comprises the following steps:

[0062] S1. Select at least one target charging station;

[0063] S2. Determine the discharge cutoff calculation value according to the charging pile position corresponding to the target charging pile;

[0064] S3. When the discharge cut-off calculation value is valid, the discharge cut-off execution value is determined according to the discharge cut-off calculation value; the discharge cut-off execution value represents the minimum value of the state of charge that needs to be retained when the power battery is discharged;

[0065] S4. Execute discharge control on the power battery of the electric vehicle according to the discharge cut-off execution value.

[0066] In this embodiment, an application scenario of the electric vehicle power battery discharge control method is: a user (generally the driver or owner of the vehicle) drives an electric vehicle to travel. When driving to a certain location, the user wants to find a charging pile to charge the power battery of the vehicle, or the battery management system reminds the user to find a charging pile to charge the power battery of the vehicle; since there is no charging pile that can provide charging immediately at the current location of the vehicle, the navigation module is used to find an available charging pile nearby; since there is a certain distance between the available charging pile and the vehicle, it is necessary to perform discharge control on the power battery of the electric vehicle so that there is enough power in the power battery to drive the vehicle to the available charging pile for charging.

[0067] In this embodiment, the specific process of steps S1-S4 is as follows Figure 3 shown.

[0068] In step S1, the navigation module can locate the vehicle and obtain the current location of the vehicle. The communication module can search the Internet (such as the server of the map service provider) according to the current location of the vehicle to obtain the location of the nearby charging piles. The communication module may search for the locations of multiple candidate charging piles, and these candidate charging piles can be screened (for example, those that are out of order, have multiple people in line, or are too far away) and the remaining candidate charging piles can be determined as target charging piles. On this basis, the navigation module can display these target charging piles to the user for viewing, and the user can further screen these target charging piles.

[0069] In this embodiment, it is assumed that step S1 is executed to determine multiple target charging piles, such as target charging pile 1, target charging pile 2, target charging pile 3, target charging pile 4, and target charging pile 5. Figure 4 Each target charging pile has a corresponding charging pile position, and the vehicle also has a corresponding current position of the vehicle. The charging pile position and the current position of the vehicle can be stored in the control module in the form of longitude and latitude.

[0070] In step S2, since the charging pile positions of each target charging pile and the current position of the vehicle are known, the distance between the vehicle and each target charging pile and other parameters can be calculated respectively, and it is estimated how much power the vehicle will consume if it drives to each of these target charging piles respectively, so as to arrange the state of charge of the power battery of the vehicle and determine the discharge cut-off calculated value of the power battery. Among them, the discharge cut-off calculated value is a calculated value with the dimension of the state of charge SOC, which indicates that the lowest value of the state of charge that the power battery needs to retain is estimated through the calculation result. Only by controlling the state of charge of the power battery to be not lower than the discharge cut-off calculated value or the approximate level can it be ensured that the power battery has enough power for the electric vehicle to drive to the target charging pile corresponding to the discharge cut-off calculated value for charging.

[0071] For example, if the vehicle needs to drive to a target charging pile that is farther away and has more congested traffic on the road, more power reserves are generally required. Therefore, a higher discharge cut-off calculation value can be set in step S2, so that the discharge cut-off execution value (also a value with the dimension of state of charge SOC, which is the minimum value of the state of charge that the power battery needs to retain when discharge control is actually performed on the power battery) determined by calculation based on the discharge cut-off calculation value is expected to be higher, thereby enabling the power battery to retain more power reserves; on the contrary, if the vehicle needs to drive to a target charging pile that is closer and has smoother traffic on the road, less power reserves are generally required. Therefore, a lower discharge cut-off calculation value can be set in step S2, thereby enabling the power battery to retain less power reserves.

[0072] In step S2, after the discharge cutoff calculation value is calculated, it is further possible to check whether the discharge cutoff calculation value is valid. In this embodiment, as long as the discharge cutoff calculation value can be calculated, the discharge cutoff calculation value is determined to be valid; and when the data required for calculating the discharge cutoff calculation value cannot be obtained, since the discharge cutoff calculation value cannot be calculated, the discharge cutoff calculation value is determined to be invalid (the discharge cutoff calculation value in this case may be "null" or the like).

[0073] In step S2, for any charging pile position corresponding to a target charging pile, a corresponding discharge cut-off calculation value is calculated. Thus, when multiple target charging piles are determined in step S1, multiple discharge cut-off calculation values ​​will be calculated in step S2.

[0074] When it is determined that the discharge cutoff calculated value is valid (in this embodiment, as long as a meaningful discharge cutoff calculated value can be calculated, the discharge cutoff calculated value is determined to be valid), in step S3, the discharge cutoff execution value is determined according to the discharge cutoff calculated value.

[0075] In this embodiment, when only one target charging pile is determined in step S1, only one discharge cut-off calculation value is obtained in step S2, and this discharge cut-off calculation value can be directly determined as the discharge cut-off execution value in step S3; when multiple target charging piles are determined in step S1, multiple discharge cut-off calculation values ​​will be obtained in step S2, and the average value of these discharge cut-off calculation values ​​can be calculated in step S3, and the average value is determined as the discharge cut-off execution value.

[0076] In step S4, the control module sends the discharge cut-off execution value to the battery management system, and the battery management system performs discharge control on the power battery of the electric vehicle according to the discharge cut-off execution value.

[0077] Specifically, in step S4, the battery management system can monitor the current state of charge SOC of the power battery. realtim e, at the current state of charge SOC realtime Greater than the discharge cut-off execution value SOC cut-off-implement In this case, the battery management system does not limit the discharge of the power battery. The power battery can be discharged according to the power demand of the power components in the electric vehicle (such as audio and video entertainment system, car cooking system, external power supply system, etc.); if the current state of charge SOC realtime The SOC drops to the discharge cut-off execution value cut-off-implement If the power level is equal to or lower than the discharge level, the battery management system limits the discharge of the power battery. For example, in the "normal power limit mode", the power battery no longer discharges externally, so that in the "normal power limit mode", the power battery always maintains the discharge cut-off execution value SOC cut-off-implement The state of charge at a certain level is due to the discharge cut-off execution value SOC cut-off-implement It is the power battery level that can guarantee the vehicle to reach the target charging pile, so it can provide power guarantee for the vehicle to drive to the target charging pile; and the discharge cut-off execution value SOC determined by steps S1-S3 cut-off-implement It is determined according to factors such as the location of the charging pile, that is, steps S1-S4 are based on the dynamically determined discharge cut-off execution value SOC cut-off-implementTo control the discharge of the power battery, the state of charge of the power battery can be kept at a level that just meets the target charging pile, which can avoid the power battery being controlled too conservatively and affecting the use of electric components such as the audio-visual entertainment system, the on-board cooking system, and the external power supply system on the electric vehicle, and can also avoid the power battery being controlled too aggressively and causing the power battery to be over-discharged, or causing the power battery to retain a low state of charge and unable to support the electric vehicle to drive to the location of the target charging pile. Therefore, steps S1-S4 can improve the flexibility of the use of electric vehicles, which is conducive to reducing or eliminating the user's range anxiety.

[0078] For example, before heading to a target charging station, the user can execute step S4 to operate in the "normal power limit mode", and the power battery is always charged at a state greater than the discharge cut-off execution value SOC cut-off-implement It can be discharged normally when it drops to the discharge cut-off execution value SOC cut-off-implement The control module can automatically cut off the power supply (or reduce the discharge power) when the power battery is over-discharged, so that users can use it with confidence without worrying about the over-discharge of the power battery. The control module can enter the "normal discharge mode" through automatic switching or manual switching by the user. For example, when the user decides to drive the car to a certain target charging pile, the control module switches to the "normal discharge mode". In the "normal discharge mode", the control module sets a smaller value (for example, 5% or 0%) as the discharge cut-off execution value, and controls the battery management system to charge at the current state of charge SOC. realtime Before it is greater than 5%, the discharge of the power battery is no longer restricted, thereby lifting the discharge restriction on the power battery.

[0079] In this embodiment, refer to Figure 3 When the discharge cutoff calculation value is invalid, for example, the discharge cutoff calculation value cannot be calculated, the control module can obtain the discharge cutoff default value SOC cut-off-default , discharge cut-off default value SOC cut-off-default It can be a fixed value, such as 20%, so that when executing step S3, the discharge cut-off execution value SOC cut-off-implement Set to discharge cut-off default value SOC cut-off-default , i.e. SOC cut-off-implement =SOC cut-off-default = 20%, thereby ensuring that the discharge cut-off execution value SOC can be determined in step S4. cut-off-implement Discharge limitation is performed.

[0080] In this embodiment, refer to Figure 3 , the discharge cut-off default value SOC is set in the control module cut-off-default (e.g. 20%), it can also detect whether the user has entered the discharge cut-off setting value SOC cut-off-setup;Discharge cut-off setting value SOCc ut-off-setup The specific value of can be determined by the user according to his / her own wishes, but in this embodiment, only the discharge cut-off setting value SOC cut-off-setup In the allowable range (the lower limit is the discharge cut-off default value SOC cut-off-default , the upper limit is the current state of charge SOC realtime , that is, [SOC cut-off-default , SOC realtime ]) within the range, that is, to meet SOC cut-off-default ≤SOC cut-off-setup ≤SOC realtime , when executing step S3, the discharge cut-off execution value SOC cut-off-implement Set to discharge cut-off setting value SOC cut-off-setup , i.e. SOC cut-off-implement =SOC cut-off-setup Otherwise, the discharge cut-off execution value SOC cut-off-implement Set to discharge cut-off default value SOC cut-off-default , i.e. SOC cut-off-implement =SOC cut-off-default =20%.

[0081] In this embodiment, by setting the discharge cut-off default value SOC cut-off-default , which can ensure that in certain circumstances, the discharge cut-off execution value SOC can be determined in step S4. cut-off-implement In other cases, the discharge cut-off setting value SOC can be set according to the user. cut-off-setup To determine the discharge cut-off execution value SOC cut-off-implement , thereby allowing users to manually adjust the discharge control of the power battery and improve flexibility.

[0082] In this embodiment, when executing step S2, a corresponding discharge cut-off calculation value may be determined for each target charging pile. Since the principle of calculating the discharge cut-off calculation value for different target charging piles may be the same, in this embodiment, the calculation Figure 4 The discharge cut-off calculation value corresponding to the target charging pile 1 in FIG. 1 is used as an example to illustrate.

[0083] In step S2, the control module can call the battery management system to read the total battery capacity B of the power battery. cap , Temperature coefficient k T and the redundancy coefficient c 冗余 Among them, the total battery capacity B cap It is the amount of electricity that the power battery can store when fully charged. The temperature coefficient k T Indicates that the storage capacity of the power battery is affected by temperature, and the redundancy coefficient c 冗余Indicates the amount of power redundancy required to achieve the discharge target, the total battery capacity B cap , Temperature coefficient k T and the redundancy coefficient c 冗余 They can all be obtained through experimental calibration and other methods, and stored as fixed values ​​in the battery management system.

[0084] In this embodiment, the total battery capacity B cap , Temperature coefficient k T and the redundancy coefficient c 冗余 This is information related to the vehicle's power battery, collectively referred to as vehicle battery information.

[0085] In step S2, the control module can call the navigation module to execute the navigation algorithm, perform route planning according to the current position of the vehicle and the charging pile position of the target charging pile 1, and obtain the expected driving route 1. The navigation module can directly output the driving distance D corresponding to the expected driving route 1, and send the coordinates of the expected driving route 1 to the communication module, and the communication module queries the real-time ambient temperature T along the way according to the coordinates of the expected driving route 1, where the ambient temperature T is generally a fixed value (if the temperature at different places along the expected driving route 1 is different, the average temperature can be calculated as the ambient temperature T). The communication module queries the terrain (such as slope ratio, road type) and congestion level of the expected driving route 1 according to the coordinates of the expected driving route 1, and obtains the average driving power consumption C by looking up a table or the like. avg , average driving power consumption C avg Indicates the electric energy consumed by the vehicle per unit mileage on the estimated driving route 1.

[0086] In this embodiment, the driving distance D, the ambient temperature T and the average driving power consumption C avg This is information related to the estimated driving route 1, collectively referred to as the along-the-way environment information of the estimated driving route 1.

[0087] In this embodiment, the total battery capacity B cap , Temperature coefficient k T and the redundancy coefficient c 冗余 The battery information of the vehicle is generally easy to obtain, but the driving distance D, ambient temperature T and average driving power consumption C avg Environmental information along the way may not be searchable. If environmental information along the way cannot be searched, the discharge cutoff calculation value corresponding to the target charging pile 1 cannot be calculated. At this time, the value of the discharge cutoff calculation value can be determined as "null", and the discharge cutoff calculation value is determined to be invalid when executing step S3. If environmental information along the way can be searched, a meaningful discharge cutoff calculation value can be calculated together with the battery information of the vehicle. As long as the discharge cutoff calculation value can be calculated, the discharge cutoff calculation value is determined to be valid when executing step S3.

[0088] In this embodiment, after obtaining the total battery capacity B corresponding to the target charging pile 1 cap , initial state of charge SOC initial , Temperature coefficient k r and the redundancy coefficient c 冗余 The vehicle's battery information, as well as driving distance D, ambient temperature T and average driving power consumption C avg After obtaining the environmental information along the way, the discharge cut-off calculation value corresponding to the target charging pile 1 can be calculated by the following formula:

[0089] E required =D×C avg ×(1+k T ×T) (1)

[0091]

[0092] SOC cut-off-compute =SOC theoretical ×(1+c 冗余 ) (3)

[0094] In this embodiment, the meaning of formula (1) is: D×C avg The power consumed by the electric vehicle to drive to the target charging pile 1 without considering the temperature effect. On this basis, the influence of the ambient temperature T of the expected driving route 1 is considered and multiplied by the coefficient (1+kT × T), thereby obtaining the power E consumed by the electric vehicle to drive to the target charging pile 1 required .

[0095] In this embodiment, the meaning of formula (2) is: the amount of electricity E required for the electric vehicle to drive to the target charging pile 1 required Divide by the total battery capacity B cap The obtained ratio It is the state of charge that the electric vehicle needs to consume when driving to the target charging station 1, that is, the state of charge SOC that the power battery theoretically needs to retain theoretical .

[0096] In this embodiment, the meaning of formula (3) is: the state of charge SOC that the power battery theoretically needs to retain theoretical Based on the coefficient (1+c 冗余 ), which can be retained redundantly to ensure the use of electric vehicles. Finally, the discharge cutoff calculation value SOC corresponding to the target charging pile 1 is obtained cut-off-compute The redundancy coefficient c 冗余 The value can be 20% etc.

[0097] The discharge cut-off calculated value SOC is obtained by using the above formulas (1)-(3) taking the target charging pile 1 as an example. cut-off-compute Can be used to determine the discharge cut-off execution value SOC cut-off-implement , ensuring that the power battery of the electric vehicle has sufficient power to support the electric vehicle to reach the location of the target charging pile 1.

[0098] In this embodiment, target charging pile 2, target charging pile 3, etc. and other target charging piles can be calculated using formulas (1)-(3) to obtain their corresponding discharge cut-off calculation values.

[0099] In this embodiment, when the control module executes step S4, that is, the step of executing discharge control on the power battery of the electric vehicle according to the discharge cut-off execution value, the control module may specifically execute the following steps:

[0100] S401. When a target charging pile is selected, discharge control is performed on the power battery of the electric vehicle with the discharge cut-off execution value corresponding to the target charging pile;

[0101] S402. When multiple target charging piles are selected, the discharge cutoff calculation value corresponding to each target charging pile is obtained, and the discharge cutoff execution value is fitted according to the position of each charging pile to obtain a discharge cutoff curve;

[0102] S403. According to the discharge cut-off curve, determine a discharge cut-off calculation value as a discharge cut-off execution value to perform discharge control on the power battery of the electric vehicle.

[0103] If only one target charging pile (eg, target charging pile 1 ) is selected in step S1 , then step S401 is executed to perform discharge control on the power battery of the electric vehicle with the discharge cutoff execution value corresponding to the target charging pile 1 .

[0104] If multiple target charging piles (eg, target charging pile 1, target charging pile 2, target charging pile 3, target charging pile 4, and target charging pile 5) are selected in step S1, then step S402 is executed.

[0105] In step S402, since the target charging pile 1, the target charging pile 2, the target charging pile 3, the target charging pile 4 and the target charging pile 5 have corresponding discharge cut-off calculation values ​​SOC cut-off-compute As well as the distance from the vehicle, a coordinate system can be established with the “distance from the vehicle” as the horizontal axis and the “state of charge” as the vertical axis. In this coordinate system, the points corresponding to target charging pile 1, target charging pile 2, target charging pile 3, target charging pile 4 and target charging pile 5 are determined, such as Figure 5 shown.

[0106] In step S402, refer to Figure 6, execute the curve fitting algorithm, fit the points corresponding to the target charging pile 1, the target charging pile 2, the target charging pile 3, the target charging pile 4 and the target charging pile 5 respectively, and obtain the discharge cut-off curve.

[0107] In this embodiment, the discharge cut-off curve is generally not a straight line. Figure 7 , the related technology generally sets a fixed discharge cut-off value (for example, the discharge cut-off default value SOC is 20%). cut-off-default ) to limit the discharge of the power battery, and according to Figure 7 It can be seen that the discharge cut-off execution value can be dynamically set in the electric vehicle power battery discharge control method in this embodiment. According to the target charging pile to be selected, the discharge cut-off execution value finally determined may be greater than, equal to or less than the fixed discharge cut-off default value SOC cut-off-default (20%), when the discharge cut-off execution value is less than the fixed discharge cut-off default value SOC cut-off-default (20%), the power battery will have more power as dynamic release power for other on-board electrical components such as the audio and video entertainment system; when the discharge cut-off execution value is greater than the fixed discharge cut-off default value SOC cut-off-default (20%), the power battery will have more power as dynamic reserve power to ensure the use of electrical components such as motors, thereby ensuring that the electric vehicle can be driven to the target charging station.

[0108] In this embodiment, when executing step S403, the control module calculates the linearity of each point on the discharge cut-off curve. Specifically, the linearity indicates the degree to which a certain curve segment on the discharge cut-off curve is close to a straight line. For example, the radius of curvature (the inverse of the curvature) of each point on the discharge cut-off curve can be calculated as the linearity. The larger the radius of curvature, the greater the linearity. When the curvature approaches infinity, the curve segment approaches a straight line.

[0109] In this embodiment, refer to Figure 8 , by calculating, it is determined that the section of the discharge cut-off curve framed by the dotted line has the largest linearity, that is, is closest to the straight line. In step S403, the discharge cut-off calculated value located on this curve segment (by Figure 6 and Figure 8 By comparing the position of , it can be determined that it is the discharge cutoff calculation value corresponding to the target charging pile 3; if there is no discharge cutoff calculation value on this curve segment, the discharge cutoff calculation value closest to this curve segment can be selected as the only discharge cutoff execution value to perform discharge control on the power battery of the electric vehicle.

[0110] For example, in this embodiment, referring to Figure 8The discharge cutoff calculation value corresponding to the target charging pile 3 is selected as the only discharge cutoff execution value, and discharge control is performed on the power battery of the electric vehicle, so that the power in the power battery can at least maintain a level that can ensure that the electric vehicle can drive to the target charging pile 3.

[0111] When executing step S403, refer to Figure 8 The discharge cutoff calculation value corresponding to the target charging pile 3 is selected as the only discharge cutoff execution value, so the navigation module will generate navigation information to instruct the user to drive the electric vehicle to the target charging pile 3.

[0112] In this embodiment, the principle of executing steps S401-S403 is that the discharge cut-off calculation value of each target charging pile can be calculated by formulas (1)-(3); for the same target charging pile, by substituting formulas (1) and (2) into formula (3), it can be obtained

[0113]

[0114]

[0115] According to formula (4), the discharge cut-off calculation value SOC cut-off-compute As a function of the driving distance D, due to the different temperature coefficients k corresponding to different target charging piles T 、Total battery capacity B cap and the redundancy coefficient c 冗余 are the same (all constants), so the values ​​in brackets are constants, but due to the different average driving power consumption C of different target charging piles avg and the ambient temperature T are not necessarily the same, so the average driving power consumption C in formula (4) avg and ambient temperature T are variables, the discharge cut-off calculation value SOC cut-off-compute It is generally not a linear function of the driving distance D; by executing steps S401-S403, the "discharge cut-off calculation value SOC cut-off-compute The target charging piles that are (or are closest to) the linear function of the driving distance D are searched out. Since these different target charging piles form the above linear function, their average driving power consumption C avg and the ambient temperature T tend to be constant, so it is preferred to select such a target charging pile to perform discharge restriction (reserve enough power to go to such a target charging pile) and navigation (drive the electric vehicle to such a target charging pile), which is beneficial to obtain a stable average driving power consumption C avgand ambient temperature T, reducing the extra loss of the power battery due to the instability of these factors, ensuring that the power battery has a greater chance of driving to the target charging pile when the power is low; on the other hand, since different target charging piles have a stable average driving power consumption C avg and ambient temperature T, these target charging piles are more likely to be located in similar positions (for example, a target charging pile is on the way to another target charging pile). This is conducive to reaching other target charging piles when driving to a certain target charging pile, ensuring the possibility of the electric vehicle finding the target charging pile.

[0116] A computer program for executing the electric vehicle power battery discharge control method in this embodiment can be written and written into a computer device or storage medium. When the computer program is read out and run, the electric vehicle power battery discharge control method in this embodiment is executed, thereby achieving the same technical effect as the electric vehicle power battery discharge control method in the embodiment.

[0117] It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly fixed or connected to the other feature, or it may be indirectly fixed or connected to the other feature. In addition, the descriptions of up, down, left, right, etc. used in the present disclosure are only relative to the relative positional relationship of the components of the present disclosure in the accompanying drawings. The singular forms of "a", "" and "the" used in the present disclosure are also intended to include the plural forms, unless the context clearly indicates other meanings. In addition, unless otherwise defined, all technical and scientific terms used in this embodiment have the same meaning as those generally understood by those skilled in the art. The terms used in the specification of this embodiment are only for describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in this embodiment includes any combination of one or more related listed items.

[0118] It should be understood that, although the term first, second, third etc. may be adopted to describe various elements in the present disclosure, these elements should not be limited to these terms. These terms are only used to distinguish the same type of elements from each other. For example, without departing from the scope of the present disclosure, the first element may also be referred to as the second element, and similarly, the second element may also be referred to as the first element. The use of any and all examples or exemplary language ("for example", "such as" etc.) provided by the present embodiment is only intended to better illustrate embodiments of the present invention, and unless otherwise required, the scope of the present invention will not be limited.

[0119] It should be appreciated that embodiments of the present invention may be implemented or enforced by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable memory. The method may be implemented in a computer program using standard programming techniques - including a non-transitory computer-readable storage medium configured with a computer program, wherein the storage medium so configured causes the computer to operate in a specific and predefined manner - according to the methods and drawings described in the specific embodiments. Each program may be implemented in a high-level procedural or object-oriented programming language to communicate with a computer system. However, if desired, the program may be implemented in assembly or machine language. In any case, the language may be a compiled or interpreted language. In addition, the program may be run on a programmed dedicated integrated circuit for this purpose.

[0120] In addition, the operations of the process described in this embodiment may be performed in any suitable order, unless otherwise indicated in this embodiment or otherwise clearly contradicted by the context. The process described in this embodiment (or variations and / or combinations thereof) may be performed under the control of one or more computer systems configured with executable instructions, and may be implemented as a code (e.g., executable instructions, one or more computer programs, or one or more applications) executed on one or more processors in common, by hardware or a combination thereof. A computer program includes a plurality of instructions that may be executed by one or more processors.

[0121] Further, the method can be implemented in any type of computing platform that is operably connected to a suitable computer, including but not limited to a personal computer, a minicomputer, a mainframe, a workstation, a network or distributed computing environment, a separate or integrated computer platform, or in communication with a charged particle tool or other imaging device, etc. Various aspects of the present invention can be implemented in machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, an optical read and / or write storage medium, a RAM, a ROM, etc., so that it can be read by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the process described herein. In addition, the machine-readable code, or part thereof, can be transmitted via a wired or wireless network. When such media includes instructions or programs that implement the above steps in conjunction with a microprocessor or other data processor, the invention of this embodiment includes these and other different types of non-transitory computer-readable storage media. When programmed according to the methods and techniques of the present invention, the present invention also includes the computer itself.

[0122] The computer program can be applied to input data to perform the functions of the present embodiment, thereby converting the input data to generate output data stored in a non-volatile memory. The output information can also be applied to one or more output devices such as a display. In a preferred embodiment of the present invention, the converted data represents a physical and tangible object, including a specific visual depiction of the physical and tangible object produced on the display.

[0123] The above are only preferred embodiments of the present invention. The present invention is not limited to the above embodiments. As long as the technical effects of the present invention are achieved by the same means, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention. Within the scope of protection of the present invention, its technical solutions and / or implementation methods may have various modifications and changes.

Claims

1. A method for controlling the discharge of a power battery of an electric vehicle, characterized in that: The electric vehicle power battery discharge control method comprises: Select at least one target charging pile; Determining a discharge cutoff calculation value according to a charging pile position corresponding to the target charging pile; When the discharge cutoff calculation value is valid, a discharge cutoff execution value is determined according to the discharge cutoff calculation value; the discharge cutoff execution value represents the minimum value of the state of charge that needs to be retained when the power battery is discharged; According to the discharge cut-off execution value, discharge control is performed on the power battery of the electric vehicle.

2. The electric vehicle power battery discharge control method according to claim 1, characterized in that: The step of determining the discharge cutoff calculation value according to the charging pile position corresponding to the target charging pile includes: Get the current position of the vehicle; Get the vehicle battery information; Perform route planning based on the current position of the vehicle and the position of the charging pile to obtain an estimated driving route; Determine the environmental information along the route according to the predicted driving route; the environmental information along the route represents the information of the environment of the location passed by the predicted driving route; When the along-the-way environmental information can be determined, the discharge cut-off calculated value is determined according to the along-the-way environmental information and the vehicle battery information, and the discharge cut-off calculated value is determined to be valid.

3. The electric vehicle power battery discharge control method according to claim 2, characterized in that: The step of determining the discharge cutoff calculation value according to the charging pile position corresponding to the target charging pile includes: When the along-the-way environmental information cannot be determined, it is determined that the discharge cut-off calculation value is invalid.

4. The electric vehicle power battery discharge control method according to claim 2, characterized in that: The obtaining of vehicle battery information includes: Obtain the total battery capacity, initial state of charge, temperature coefficient and redundancy coefficient of the power battery; The total battery capacity, the initial state of charge, the temperature coefficient and the redundancy coefficient are used as the battery information of the vehicle; The determining of the environmental information along the route according to the estimated driving route includes: According to the estimated driving route, query the driving distance, ambient temperature and average driving power consumption; The driving distance, the ambient temperature and the average driving power consumption are used as the environmental information along the way.

5. The electric vehicle power battery discharge control method according to claim 4, characterized in that: The step of determining the discharge cut-off calculation value according to the on-road environment information and the vehicle battery information includes: According to the formula E required =D×C avg ×(1+k T ×T) SOCIETY cut-off-compute =SOC theoretical ×(1+c 冗余 ) Calculation is performed to determine the discharge cut-off calculation value; wherein, SOC cut-off-compute is the discharge cut-off calculation value, D is the driving distance, T is the ambient temperature, C avg is the average driving power consumption, k T is the temperature coefficient, c 冗余 is the redundancy coefficient, B cap is the total capacity of the battery, SOC initial is the initial state of charge.

6. The electric vehicle power battery discharge control method according to claim 1, characterized in that: The electric vehicle power battery discharge control method further includes: When the discharge cutoff calculated value is invalid, obtaining a discharge cutoff default value; Detect the current state of charge of the power battery; Detect the discharge cut-off setting value set by the user; When the discharge cutoff setting value is detected, determining the relative size of the discharge cutoff setting value; When the discharge cutoff setting value is within the range of the allowable interval, the discharge cutoff setting value is determined as the discharge cutoff execution value; the upper limit of the allowable interval is the current state of charge, and the lower limit is the discharge cutoff default value; When the discharge cutoff setting value is not detected, or the discharge cutoff setting value is outside the allowable interval, the discharge cutoff default value is determined as the discharge cutoff execution value.

7. The electric vehicle power battery discharge control method according to any one of claims 1 to 6, characterized in that: The method of executing discharge control on the power battery of the electric vehicle according to the discharge cut-off execution value includes: When one of the target charging piles is selected, discharge control is performed on the power battery of the electric vehicle according to the discharge cut-off execution value corresponding to the target charging pile; When a plurality of target charging piles are selected, the discharge cutoff calculation value corresponding to each of the target charging piles is obtained, and each of the discharge cutoff calculation values ​​is fitted according to the position of each charging pile to obtain a discharge cutoff curve; According to the discharge cut-off curve, a discharge cut-off execution value is determined to perform discharge control on the power battery of the electric vehicle.

8. The electric vehicle power battery discharge control method according to claim 7, characterized in that: The step of determining a discharge cutoff execution value according to the discharge cutoff curve to perform discharge control on the power battery of the electric vehicle comprises: Obtaining the linearity of each point on the discharge cut-off curve; Determine the curve segment with the maximum linearity corresponding to the discharge cut-off curve; A corresponding one of the discharge cutoff calculation values ​​is determined on the curve segment and used as the discharge cutoff execution value to execute discharge control on the power battery of the electric vehicle.

9. A computer device, characterized in that: It comprises a memory and a processor, the memory is used to store at least one program, and the processor is used to load at least one program to execute the electric vehicle power battery discharge control method as described in any one of claims 1-8.

10. A computer-readable storage medium storing a program executable by a processor, characterized in that: The program executable by the processor is used to execute the electric vehicle power battery discharge control method as described in any one of claims 1 to 8 when executed by the processor.

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