Vehicle-to-vehicle mutual charging control method, vehicle-mounted controller, vehicle, and storage medium

Abstract

The application discloses a vehicle-to-vehicle mutual charging control method, a vehicle-mounted controller, a vehicle and a storage medium. The method comprises the following steps: acquiring a maximum allowed total discharge voltage value of a discharging vehicle, and sending the maximum allowed total discharge voltage value to a charging vehicle; receiving a direct-current charging type and a required voltage value determined by the charging vehicle based on the maximum allowed total discharge voltage value; if the direct-current charging type is step-up direct-current charging, performing step-up discharge control based on the required voltage value, and enabling the charging vehicle to perform step-down charging control according to a real-time voltage of a battery. The scheme can guarantee the safety of direct-current charging when step-up direct-current charging is performed.

Description

Technical Field

[0001] This invention relates to the field of vehicle-to-vehicle charging control technology, and in particular to a vehicle-to-vehicle charging control method, an on-board controller, a vehicle, and a storage medium. Background Technology

[0002] Standard DC charging in China typically uses charging stations to charge vehicles. The maximum allowable discharge voltage of a charging station is the maximum output voltage of its internal charging module, usually set to a fixed value. Vehicle-to-Vehicle (VTOV) technology involves using a discharging vehicle to DC charge another vehicle. In existing VTOV technologies, the discharging vehicle, similar to the charging station, charges the charging vehicle based on its highest output voltage. This method cannot adapt to scenarios where the discharging and charging vehicles have the same or different maximum output voltages, raising concerns about charging safety. Summary of the Invention

[0003] This invention provides a vehicle-to-vehicle charging control method, an on-board controller, a vehicle, and a storage medium to solve the problem that existing vehicle-to-vehicle charging systems cannot guarantee charging safety.

[0004] A vehicle-to-vehicle charging control method includes:

[0005] Obtain the maximum permissible total discharge voltage value of the discharging vehicle and send the maximum permissible total discharge voltage value to the charging vehicle;

[0006] Receive the DC charging type and required voltage value determined by the charging vehicle based on the maximum permissible total discharge voltage value;

[0007] If the DC charging type is boost DC charging, then boost discharge control is performed based on the required voltage value, and the charging vehicle performs buck charging control based on the real-time battery voltage.

[0008] Preferably, the maximum permissible total discharge voltage value is the difference between the actual battery voltage of the discharging vehicle and the first differential voltage threshold.

[0009] Preferably, the first differential pressure threshold ranges from 10V to 30V.

[0010] Preferably, the maximum allowable total discharge voltage value is the larger of the battery's allowable total discharge voltage value and the first preset total voltage value;

[0011] The battery's allowable total discharge voltage value is the difference between the battery's lower limit discharge total voltage value and the second differential voltage threshold.

[0012] The total lower discharge voltage of the battery is the product of the number of battery cells in the discharging vehicle and the lower discharge voltage of a single battery cell.

[0013] Preferably, the range of the first preset total voltage value is 400V-550V; and / or,

[0014] The lower limit discharge voltage of the single battery cell is in the range of 3V-3.2V; and / or,

[0015] The second differential pressure threshold ranges from 10V to 30V.

[0016] Preferably, the boost discharge control based on the required voltage value includes:

[0017] If the target voltage value of the discharging vehicle does not reach the required voltage value, then the charging vehicle is discharged based on the first current and the target voltage value, and the target voltage value is boosted based on a preset voltage regulation rate to obtain an updated target voltage value; and / or

[0018] If the target voltage value of the discharging vehicle reaches the required voltage value, then the required voltage value is determined as the target voltage value, and the charging vehicle is discharged based on the second current and the target voltage value, while monitoring the current SOC value of the discharging vehicle; when the current SOC value is less than the preset SOC value, the discharge to the charging vehicle is stopped.

[0019] The second current is greater than the first current.

[0020] Preferably, the value of the first current ranges from 10A to 50A; and / or,

[0021] The value range of the second current is 100A-125A.

[0022] Preferably, after receiving the DC charging type and required voltage value determined by the charging vehicle based on the maximum permissible total discharge voltage value, the vehicle-to-vehicle charging control method further includes:

[0023] If the DC charging type is non-boost DC charging, then non-boost discharge control is performed based on the required voltage value.

[0024] Preferably, the non-boost discharge control based on the required voltage value includes:

[0025] Discharge is performed based on the third current and target voltage value, and the current SOC value is monitored. When the current SOC value is less than the preset SOC value, the discharge to the charging vehicle is stopped.

[0026] The target voltage value is the difference between the required voltage value and the third differential voltage threshold.

[0027] Preferably, the value of the third current is in the range of 100A-125A, and / or,

[0028] The value range of the third differential pressure threshold is 10V-30V.

[0029] A vehicle-to-vehicle charging control method includes:

[0030] Receive the maximum permissible total discharge voltage value sent by the discharge vehicle;

[0031] The DC charging type is determined based on the maximum permissible total discharge voltage value;

[0032] The required voltage value for the charging vehicle is determined based on the maximum permissible total discharge voltage value.

[0033] If the DC charging type is boost DC charging, the required voltage value is sent to the discharging vehicle so that the discharging vehicle performs boost discharge control based on the required voltage value and buck charging control based on the real-time battery voltage of the charging vehicle.

[0034] Preferably, the vehicle-to-vehicle charging control method further includes:

[0035] If the DC charging type is non-boost DC charging, the required voltage value is sent to the discharging vehicle so that the discharging vehicle can perform non-boost discharge control based on the required voltage value.

[0036] Preferably, determining the DC charging type based on the maximum permissible total discharge voltage includes:

[0037] Obtain the maximum permissible total charging voltage value for the charging vehicle;

[0038] If the maximum permissible total discharge voltage is less than the maximum permissible total charging voltage, then the DC charging type is determined to be boost DC charging; and / or

[0039] If the maximum allowable total discharge voltage is not less than the maximum allowable total charging voltage, then the DC charging type is determined to be non-boost DC charging.

[0040] Preferably, the maximum permissible total charging voltage of the charging vehicle is the smaller of the highest permissible total charging voltage of the charging vehicle and the second preset total voltage value.

[0041] Preferably, the range of the second preset total voltage value is 600V-800V.

[0042] Preferably, the required voltage value of the charging vehicle is the difference between the maximum allowable total discharge voltage value and the fourth differential voltage threshold.

[0043] Preferably, the fourth differential pressure threshold ranges from 10V to 30V.

[0044] Preferably, the step-down charging control based on the real-time battery voltage of the charging vehicle includes:

[0045] If the voltage reduction target value is not reached, the charging vehicle is charged based on the voltage reduction target value, and the voltage reduction target value is processed based on a preset voltage regulation rate to obtain an updated target voltage reduction value; and / or

[0046] If the voltage reduction target value reaches the maximum voltage reduction value, then the charging vehicle is charged based on the maximum voltage reduction value;

[0047] The target voltage reduction value and the maximum voltage reduction value are determined based on the real-time battery voltage of the charging vehicle and the maximum allowable total discharge voltage value.

[0048] Preferably, the voltage reduction target value of the charging vehicle is the smaller value between a first total voltage reduction value and a third preset total voltage value;

[0049] The maximum voltage drop of the charging vehicle is the smaller of the first total voltage drop value and the second total voltage drop value;

[0050] The first total voltage drop value is the difference between the real-time battery voltage of the charging vehicle and the fifth differential voltage threshold.

[0051] The second total voltage drop value is the difference between the maximum allowable total discharge voltage value and the fifth differential voltage threshold.

[0052] Preferably, the third preset total voltage value ranges from 360V to 420V; and / or

[0053] The fifth differential pressure threshold value ranges from 10V to 30V.

[0054] An on-board controller includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described vehicle-to-vehicle charging control method.

[0055] A vehicle including the aforementioned on-board controller.

[0056] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described vehicle-to-vehicle charging control method.

[0057] The aforementioned vehicle-to-vehicle charging control method, on-board controller, vehicle, and storage medium allow the discharging vehicle to communicate with the charging vehicle, sending the maximum permissible total discharge voltage value to the charging vehicle and receiving feedback from it on the DC charging type and required voltage value. When the DC charging type is boost DC charging, boost discharge control is required based on the required voltage value, and the charging vehicle is required to perform buck charging control based on its real-time battery voltage, so that the discharge voltage of the discharging vehicle gradually increases while the charging voltage of the charging vehicle gradually decreases, ensuring the safety of the discharging vehicle discharging to the charging vehicle. Attached Figure Description

[0058] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 This is a flowchart of a vehicle-to-vehicle charging control method according to an embodiment of the present invention;

[0060] Figure 2 This is another flowchart of the vehicle-to-vehicle charging control method in one embodiment of the present invention. Detailed Implementation

[0061] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0062] The vehicle-to-vehicle (V2V) charging control method provided in this invention can be applied to both discharging and charging vehicles. The discharging and charging vehicles are connected via a charging gun, allowing the discharging vehicle to DC charge the charging vehicle, thus improving the charging efficiency of the charging vehicle. The discharging vehicle is a high-voltage vehicle equipped with a motor boost controller; correspondingly, the charging vehicle can be either a high-voltage vehicle with a motor boost controller or a low-voltage vehicle without one. In this example, high-voltage and low-voltage vehicles refer to two types of vehicles determined by comparing the vehicle's maximum output voltage with a preset voltage threshold (e.g., 500V). Here, a high-voltage vehicle is one whose maximum output voltage is greater than or equal to the preset voltage threshold; correspondingly, a low-voltage vehicle is one whose maximum output voltage is less than the preset voltage threshold.

[0063] In the vehicle-to-vehicle charging control method provided in this embodiment, before the discharging vehicle discharges to the charging vehicle, the discharging vehicle and the charging vehicle must first be connected via a charging gun so that the discharging vehicle and the charging vehicle can communicate via a handshake to complete the charging and discharging control process.

[0064] The discharging vehicle sends a CHM message to the charging vehicle. That is, after the discharging vehicle and the charging vehicle are physically connected and powered on, and the voltage detection is normal, the discharging vehicle sends a CHM message to the charging vehicle every preset time (such as 250 ms) to determine whether the handshake between the two parties is normal.

[0065] After receiving the CHM message, the charging vehicle can reply with a BHM message to the discharging vehicle. Specifically, after receiving the CHM message, the charging vehicle sends a BHM message to the discharging vehicle every preset time interval (e.g., 250 ms), providing the charging vehicle's maximum permissible total charging voltage U. bhm .

[0066] The discharging vehicle sends a CRM message to the charging vehicle. Specifically, after the discharging and charging vehicles have completed their handshake and confirmed that the insulation test is normal, the discharging vehicle sends a CRM message to the charging vehicle to confirm that the communication link between them is functioning correctly. In this example, if the discharging vehicle does not receive a BHM message, it sends CRM_00 to the charging vehicle; if it receives a BHM message, it sends CRM_AA to the charging vehicle to complete the handshake confirmation.

[0067] When a charging vehicle receives a CRM_00 message from a discharging vehicle, it can determine that the discharging vehicle has not received the BHM message. The charging vehicle can then send a BRM message to the discharging vehicle to provide BMS and vehicle identification information. Conversely, when a charging vehicle receives a CRM_AA message from a discharging vehicle, it can determine that the discharging vehicle has received the BHM message. The charging vehicle can then send a BCP message to the discharging vehicle to transmit the charging vehicle's battery charging parameters.

[0068] After receiving the BCP message from the charging vehicle, the discharging vehicle can send a CML message to the charging vehicle. The CML message is the maximum output capacity message of the discharging vehicle, used to record the maximum allowable total discharge voltage value U of the discharging vehicle. cml_max .

[0069] After receiving the CML message, the charging vehicle can send a BRO message to the discharging vehicle. The BRO message is a charging ready message for the charging vehicle, allowing the discharging vehicle to confirm that the charging vehicle is ready to charge.

[0070] After receiving the BRO message, the discharging vehicle can send a CRO message to the charging vehicle. The CRO message is a ready-to-output message from the discharging vehicle, allowing the charging vehicle to confirm that the discharging vehicle is ready to output. In this example, after outputting the BRO message, the discharging vehicle can begin DC charging the charging vehicle.

[0071] During the DC charging process, the charging vehicle can send a BCS message to the discharging vehicle. The BCS message is the overall charging status message of the charging vehicle's battery, which enables the discharging vehicle to monitor the charging status of the battery pack, such as charging voltage and charging current, during the charging process.

[0072] During the DC charging process of the discharging vehicle, the discharging vehicle can send a CCS message to the charging vehicle. The CCS message is a discharge status message of the discharging vehicle, which enables the charging vehicle to monitor information such as the charging voltage and charging current value of the discharging vehicle.

[0073] In one embodiment, such as Figure 1 As shown, a vehicle-to-vehicle charging control method is provided. Taking the application of this vehicle-to-vehicle charging control method to the on-board controller of a discharging vehicle as an example, the method is explained below. The on-board controller of the discharging vehicle refers to the controller installed on the discharging vehicle. Specifically, the method includes the following steps performed by the on-board controller of the discharging vehicle:

[0074] S101: Obtain the maximum permissible total discharge voltage value of the discharging vehicle and send the maximum permissible total discharge voltage value to the charging vehicle.

[0075] S102: Receive the DC charging type and required voltage value determined by the charging vehicle based on the maximum permissible total discharge voltage value;

[0076] S103: If the DC charging type is boost DC charging, boost discharge control is performed based on the required voltage value, and the charging vehicle performs buck charging control based on the real-time battery voltage of the charging vehicle.

[0077] The maximum permissible total discharge voltage value refers to the total voltage value that the discharging vehicle is allowed to discharge to the charging vehicle, which can be expressed as U. cml_max express.

[0078] As an example, in step S101, after the discharge vehicle and the charging vehicle establish a communication link, the on-board controller of the discharge vehicle can obtain the maximum allowable total discharge voltage value U of the discharge vehicle. cml_max The maximum permissible total discharge voltage value U cml_max The maximum allowable total discharge voltage U can be determined based on the number of battery cells in the battery pack of the discharging vehicle, or based on the actual voltage of the batteries in the battery pack. In this example, the maximum allowable total discharge voltage U is determined based on the actual situation of the battery pack built into the discharging vehicle. cml_max It can be based on the maximum permissible total discharge voltage value U cml_maxThis limits the total voltage value that can be discharged to the charging vehicle in order to ensure the normal operation of the discharging vehicle.

[0079] Among them, the DC charging type is determined based on the maximum allowable total discharge voltage value and the pre-set evaluation conditions corresponding to boost DC charging, within the maximum allowable total discharge voltage value U. cml_max When the evaluation conditions for boost DC charging are met, the DC charging type is boost DC charging; otherwise, within the maximum allowable total discharge voltage value U... cml_max If the evaluation conditions for boost DC charging are not met, the DC charging type is non-boost DC charging. The required voltage value for the charging vehicle refers to the voltage value that needs to be supplied to the vehicle during DC charging, which can be expressed as U. BCL express.

[0080] As an example, in step S103, when the DC charging type is boost DC charging, the on-board controller of the discharging vehicle needs to perform boost discharge control based on the received demand voltage value of the charging vehicle, that is, first discharge based on a lower discharge voltage, and then gradually increase its discharge voltage for discharge; at the same time, the on-board controller of the charging vehicle will also discharge based on the real-time battery voltage U of the charging vehicle. bat2 The charging voltage is gradually reduced by stepping down the charging voltage. When the discharge voltage of the discharging vehicle is consistent with the charging voltage of the charging vehicle, non-boost discharge control is then implemented to avoid the charging vehicle's maximum output voltage being too high, which could affect the safety of the discharging vehicle discharging to the charging vehicle.

[0081] In this embodiment, the discharging vehicle communicates with the charging vehicle, sending the maximum allowable total discharge voltage value to the charging vehicle and receiving the DC charging type and required voltage value from it. When the DC charging type is boost DC charging, boost discharge control is required based on the required voltage value, and the charging vehicle is required to perform buck charging control based on its real-time battery voltage, so that the discharge voltage of the discharging vehicle gradually increases while the charging voltage of the charging vehicle gradually decreases, ensuring the safety of the discharging vehicle discharging to the charging vehicle.

[0082] In one embodiment, the maximum permissible total discharge voltage is the difference between the actual battery voltage of the discharging vehicle and a first differential voltage threshold.

[0083] Among them, the actual battery voltage of the discharge vehicle refers to the voltage value of the battery pack inside the discharge vehicle collected in real time, which can be expressed in U... bat1 The first differential pressure threshold is a pre-set first differential pressure value used to reflect the differential pressure between the actual battery voltage of the discharging vehicle and its total allowable discharge voltage value, and can be represented by 'a'.

[0084] As an example, the on-board controller of the discharging vehicle can obtain the actual battery voltage U of the discharging vehicle. bat1The actual battery voltage U bat1 The difference between the voltage and the first differential voltage threshold 'a' is determined as the maximum permissible total discharge voltage value U. cml_max , that is U cml_max =U bat1 -a, to ensure that the discharge voltage from the discharging vehicle to the charging vehicle reaches the maximum permissible total discharge voltage value U. cml_max The actual battery voltage U of the discharging vehicle bat1 There is a certain voltage difference between the discharge voltage and the discharge voltage, and the difference is the first voltage difference threshold a, which can ensure the normal operation of the discharge vehicle.

[0085] In one embodiment, the first differential voltage threshold ranges from 10V to 30V. For example, the first differential voltage threshold can be, but is not limited to, values ​​such as 10V, 12V, 16V, 19V, 24V, 27V, 29V, or 30V.

[0086] In this embodiment, the actual battery voltage U of the discharging vehicle is... bat1 The difference between the voltage and the first differential voltage threshold is determined as the maximum permissible total discharge voltage value U. cml_max At that time, due to the discharge process of the vehicle, the actual battery voltage U collected by it... bat1 The voltage U of the battery in the discharging vehicle changes in real time as the discharging vehicle continuously discharges into the charging vehicle. bat1 It will gradually decrease, depending on the actual battery voltage U. bat1 Dynamically adjust the maximum allowable total discharge voltage value U cml_max This causes the battery's SOC value to decrease during the discharge process of the vehicle, and the corresponding discharge voltage drop decreases accordingly, so as to ensure that the discharge power of the vehicle is maintained at its maximum capacity.

[0087] In one embodiment, the maximum allowable total discharge voltage is the larger of the battery's allowable total discharge voltage and the first preset total voltage; the battery's allowable total discharge voltage is the difference between the battery's lower limit total discharge voltage and the second differential voltage threshold; and the battery's lower limit total discharge voltage is the product of the number of battery cells in the discharging vehicle and the lower limit discharge voltage of a single battery cell.

[0088] The first preset total voltage value refers to the pre-set total discharge voltage value, which is the minimum total discharge voltage value for the discharging vehicle, and can be represented by U1. The number of battery cells in the discharging vehicle refers to the number of battery cells in the battery pack of the discharging vehicle. As an example, the number of battery cells in the discharging vehicle here can be all the battery cells in the battery pack, or all fault-free and dischargeable battery cells. The minimum discharge voltage value for a single battery cell refers to the minimum discharge voltage that each single battery cell in the battery pack needs to reach when discharging, and can be represented by d. The second differential voltage threshold is a pre-set second differential voltage value, used to ensure that the discharging vehicle can still operate normally after discharge, and can be represented by e.

[0089] The on-board controller of the discharge vehicle needs to perform the following calculations in sequence to determine the maximum allowable total discharge voltage value: (1) The product of the number of battery cells in the discharge vehicle and the lower limit discharge voltage value d of a single battery cell can be determined as the lower limit discharge voltage value of the battery in the discharge vehicle, that is, the lower limit discharge voltage value = d * number of battery cells. (2) The difference between the lower limit discharge voltage value of the battery and the second voltage difference threshold e is determined as the allowable total discharge voltage value of the battery, that is, the allowable total discharge voltage value of the battery = d * number of battery cells - e, so as to determine the allowable total discharge voltage value of the battery according to the number of battery cells of different models of discharge vehicles. Generally speaking, the number of battery cells in the battery pack loaded in each discharge vehicle is determined, and the determined allowable total discharge voltage value of the battery is a fixed value. (3) The larger value between the allowable total discharge voltage value of the battery and the first preset total voltage value is determined as the maximum allowable total discharge voltage value U. cml_max , that is U cml_maxx =max{U1, d * number of battery cells - e}. In other words, when the number of battery cells is high, the total allowable discharge voltage (i.e., d * number of battery cells - e) is greater than the first preset total voltage value U1 (e.g., 500V). In this case, the total allowable discharge voltage (i.e., d * number of battery cells - e) can be determined as the maximum allowable total discharge voltage value U. cml_max Conversely, if the total allowable discharge voltage of the battery (i.e., d * number of battery cells - e) is not greater than the first preset total voltage value U1 (e.g., 500V), then the first preset total voltage value U1 (e.g., 500V) can be determined as the maximum allowable total discharge voltage value U. cml_max .

[0090] In one embodiment, the first preset total voltage value ranges from 400V to 550V; and / or, the lower limit discharge voltage value of a single battery cell ranges from 3V to 3.2V; and / or, the second differential voltage threshold ranges from 10V to 30V.

[0091] As an example, the first preset total voltage value U1 is in the range of 400V-550V. For example, the first preset total voltage value U1 can be, but is not limited to, 400V, 420V, 450V, 467V, 488V, 500V, 532V or 550V.

[0092] As an example, the lower limit discharge voltage value d of a single battery cell ranges from 3V to 3.2V. For example, the lower limit discharge voltage value d of a single battery cell can be, but is not limited to, 3V, 3.05V, 3.11V, 3.15V, or 3.2V.

[0093] As an example, the second differential pressure threshold e can be in the range of 10V-30V. For example, the second differential pressure threshold e can be, but is not limited to, values ​​such as 10V, 13V, 16V, 20V, 23V, 27V, 28.5V, or 30V.

[0094] For example, for vehicle model A with 200 battery cells, if d is set to the optimal value of 3.0V and e to the optimal value of 30V, then d * number of battery cells - e = 570V, and the vehicle's discharge voltage is 570V. For vehicle model B with 166 battery cells, if d is set to the optimal value of 3.0V and e to the optimal value of 30V, then d * number of battery cells - e = 468V, and the maximum allowable total discharge voltage U of the vehicle is... cml_max It is 500V.

[0095] In this embodiment, the total allowable discharge voltage of the battery is determined based on the number of battery cells in the discharging vehicle, the lower limit discharge voltage of a single battery cell, and the second differential voltage threshold. The larger of the total allowable discharge voltage and the first preset total voltage is determined as the maximum allowable discharge voltage. This allows for the differentiation of the maximum allowable discharge voltage for different vehicle models based on the number of battery cells, so that subsequent discharge control can be performed based on a fixed maximum allowable discharge voltage. This ensures that the maximum allowable discharge voltage is greater than or equal to the first preset total voltage, thereby guaranteeing the safety of the discharging vehicle discharging to the charging vehicle.

[0096] In one embodiment, step S103, which involves boost discharge control based on the required voltage value, includes:

[0097] S1031: If the target voltage value of the discharging vehicle does not reach the required voltage value, then the charging vehicle is discharged based on the first current and the target voltage value, and the target voltage value is boosted based on the preset voltage regulation speed to obtain an updated target voltage value; and / or,

[0098] S1032: If the target voltage value of the discharging vehicle reaches the required voltage value, the required voltage value is determined as the target voltage value. The charging vehicle is discharged based on the second current and the target voltage value. The current SOC value of the discharging vehicle is monitored. When the current SOC value is less than the preset SOC value, the discharge to the charging vehicle is stopped.

[0099] The second current is greater than the first current.

[0100] The target voltage value of the discharging vehicle refers to the voltage value that the discharging vehicle needs to output when discharging to the charging vehicle, which can be represented by Um. The first current is a preset current, specifically the current preset during the boost phase, which can be represented by I1. The second current is a preset current, specifically the current preset during the constant voltage phase, which can be represented by I2. In this example, the second current is greater than the first current, which helps ensure that the discharge power in the constant voltage phase is greater than the discharge power during the boost and deboost phases, thus balancing the safety of the boost phase and the efficiency of the constant voltage phase. The preset voltage regulation speed is a preset voltage regulation speed, reflecting the voltage difference per unit time, which can be represented by ΔU / s. The current SOC value refers to the SOC value measured at the current moment, specifically the SOC value measured at the current moment for the battery pack of the discharging vehicle. The preset SOC value is a preset SOC value used to assess whether to stop discharging to ensure the normal operation of the discharging vehicle; for example, this preset SOC value can be set to 15%.

[0101] As an example, at the initial moment of discharging based on the required voltage value, the on-board controller of the discharging vehicle can determine a preset initial voltage as the target voltage value for the discharging vehicle. Subsequently, it can use a preset voltage adjustment rate ΔU / s to boost the target voltage value, i.e., increasing it by one ΔU per second, to obtain the updated target voltage value. In this example, after obtaining the target voltage value at the current moment, the discharging vehicle can compare the target voltage value with the required voltage value U sent by the charging vehicle. BCL The comparison is performed, and based on the comparison results, different discharge control strategies are implemented to discharge the charging vehicle.

[0102] As an example, in step S1031, the on-board controller of the discharge vehicle detects that the target voltage value of the discharge vehicle has not reached the required voltage value U. BCL If the target voltage value at the current moment does not reach the required voltage value of the charging vehicle, it can be considered that the target voltage value is too small. The charging vehicle is then discharged based on the smaller first current I1 and the target voltage value to ensure the safety of the discharging vehicle discharging the charging vehicle. This avoids the phenomenon of over-discharging the discharging vehicle and overcharging the charging vehicle due to directly discharging based on the higher second current and target voltage value. During the discharge process based on the smaller first current I1 and target voltage value, the target voltage value is boosted based on a preset voltage regulation rate ΔU / s to obtain an updated target voltage value. For example, in a unit time of 1 second, the updated target voltage value Um = Um + ΔU is obtained every 1 second. In this example, after obtaining the updated target voltage value, it is determined whether the target voltage value has reached the required voltage value in order to continue executing step S1031 or step S1032.

[0103] As an example, in step S1032, the on-board controller of the discharge vehicle reaches the required voltage value U when the target voltage value is reached. BCL If the target voltage value at the current moment reaches the required voltage value determined by the charging vehicle, the target voltage value can be considered large, and the required voltage value U can be set at that time. BCL The target voltage value is determined, and the charging vehicle is discharged based on the larger second current I2 and the target voltage value to ensure the efficiency of the discharging vehicle discharging to the charging vehicle. During the discharge process, the on-board controller of the discharging vehicle needs to monitor the current SOC value of the battery pack of the discharging vehicle and compare the monitored current SOC value with the preset SOC value. When the current SOC value is less than the preset SOC value, it is determined that the battery capacity of the discharging vehicle is small. If the discharging vehicle continues to be discharged, it will affect the normal operation of the discharging vehicle. At this time, the discharging of the discharging vehicle can be stopped.

[0104] In one embodiment, the first current ranges from 10A to 50A; and / or, the second current ranges from 100A to 125A.

[0105] As an example, the value of the first current I1 is in the range of 10A-50A. For example, the first current I1 can be, but is not limited to, 10A, 14A, 20A, 25A, 31A, 38A, 44A, 47A or 50A.

[0106] As an example, the value of the second current I2 is in the range of 100A-125A. For example, the second current I2 can be, but is not limited to, 100A, 106A, 109A, 113A, 118A, 120A or 125A.

[0107] In this embodiment, when the target voltage value of the discharging vehicle does not reach the required voltage value of the charging vehicle, discharge is first performed based on a smaller first current I1 and the target voltage value. Then, the target voltage value is boosted based on a preset voltage regulation speed to obtain an updated target voltage value, thereby ensuring the safety of the discharging vehicle discharging to the charging vehicle. When the target voltage value of the discharging vehicle reaches the required voltage value of the charging vehicle, discharge can be performed based on a larger second current I2 and the target voltage value, realizing discharge based on a larger discharge power in the constant voltage stage, thereby ensuring the efficiency of the discharging vehicle discharging to the charging vehicle.

[0108] In one embodiment, after step S103, that is, after receiving the DC charging type and required voltage value determined by the charging vehicle based on the maximum permissible total discharge voltage value, the vehicle-to-vehicle charging control method further includes:

[0109] If the DC charging type is non-boost DC charging, then non-boost discharge control is performed based on the required voltage value.

[0110] As an example, when the DC charging type of a vehicle is non-boost DC charging, the on-board controller performs non-boost discharge control based on the required voltage value, that is, according to the required voltage value U. BCL By establishing a constant discharge voltage, discharge can be performed based on this constant voltage. When the discharging vehicle discharges to the charging vehicle, its discharge voltage remains constant, eliminating the need for voltage boosting. This simplifies the control logic and improves the efficiency of the discharging vehicle discharging to the charging vehicle.

[0111] In this embodiment, the discharging vehicle communicates with the charging vehicle, sending the maximum allowable total discharge voltage value to the charging vehicle and receiving feedback from it on the DC charging type and the required voltage value. When the DC charging type is non-boost DC charging, non-boost discharge control is performed based on the required voltage value, eliminating the need for boost / boost control and improving the efficiency of the discharging vehicle discharging to the charging vehicle.

[0112] In one embodiment, non-boost discharge control based on the required voltage value includes:

[0113] Discharge is performed based on the third current and target voltage value. The current SOC value is monitored. When the current SOC value is less than the preset SOC value, the discharge to the charging vehicle is stopped.

[0114] The target voltage value is the difference between the required voltage value and the third differential voltage threshold.

[0115] The third differential pressure threshold is a pre-set third differential pressure value, which can be represented by f. The third current is a pre-set current, specifically the current pre-set during non-boost discharge control; for example, the third current can be represented by I3.

[0116] As an example, when the DC charging type of a discharge vehicle is non-boost DC charging, the on-board controller can set the required voltage value U. BCL The difference between the voltage and the third differential voltage threshold f is determined as the target voltage value Um, i.e., Um = U BCL -f. In this example, during the non-boost discharge control process of the discharging vehicle based on the demand voltage value, in order to make the boost-side voltage (i.e., the voltage of the discharging vehicle) follow the boost-side voltage (i.e., the voltage of the charging vehicle), the buck-side voltage needs to be higher than the boost-side voltage, even if the demand voltage value U of the charging vehicle is... BCL The voltage value is greater than the target voltage value Um of the discharge vehicle, resulting in a certain voltage difference between the two. Therefore, the required voltage value Um can be... BCL The difference between the voltage and the third differential voltage threshold f is determined as the target voltage value of the discharge vehicle, i.e., Um = U BCL -f=U cml_max -bf=U cml_max-(b+f) makes the voltage of the discharging vehicle gradually follow the voltage of the charging vehicle, ensuring the feasibility of the discharging vehicle providing DC charging to the charging vehicle.

[0117] As an example, when the DC charging type is non-boost DC charging, the on-board controller of the discharging vehicle first determines the difference between the required voltage value of the charging vehicle and the third voltage difference threshold f as the target voltage value of the discharging vehicle. This ensures that the voltage of the subsequent discharging vehicle can gradually follow the voltage of the charging vehicle. Then, based on the third current and the target voltage value, the charging vehicle is discharged. During the discharge process, the on-board controller of the discharging vehicle needs to monitor the current SOC value of the battery pack of the discharging vehicle and compare the monitored current SOC value with the preset SOC value. If the current SOC value is less than the preset SOC value, it is determined that the battery capacity of the discharging vehicle is small. If the discharging vehicle continues to be discharged, it will affect the normal operation of the discharging vehicle. At this time, the discharging of the charging vehicle can be stopped.

[0118] In one embodiment, the value of the third current is in the range of 100A-125A, and / or the value of the third differential voltage threshold is in the range of 10V-30V.

[0119] As an example, the value of the third current I3 is in the range of 100A-125A. For example, the third current can be, but is not limited to, 100A, 103A, 108A, 110A, 116A, 119A, 121A or 125A.

[0120] As an example, the third differential pressure threshold f can range from 10V to 30V. For example, the third differential pressure threshold f can be, but is not limited to, values ​​such as 10V, 12V, 15V, 19V, 24V, 27V, or 30V.

[0121] In this embodiment, the difference between the required voltage value and the third voltage difference threshold is determined as the target voltage value, so that the voltage of the discharging vehicle gradually follows the voltage of the charging vehicle, ensuring the feasibility of the discharging vehicle providing DC charging to the charging vehicle; then, discharging is performed based on the third current and the target voltage value. The value of the third current is in the range of 100A-125A. The discharging current of the discharging vehicle is relatively large, and the discharging voltage follows the required voltage value of the charging vehicle, so as to achieve discharging based on a large discharging power and ensure the efficiency of the discharging vehicle discharging to the charging vehicle.

[0122] In one embodiment, such as Figure 2 As shown, a vehicle-to-vehicle charging control method is provided. Taking the application of this vehicle-to-vehicle charging control method to the on-board controller of a charging vehicle as an example, the on-board controller here refers to the controller installed on the charging vehicle, specifically including the following steps of the on-board controller of the charging vehicle:

[0123] S201: Receive the maximum permissible total discharge voltage value sent by the discharge vehicle;

[0124] S202: Determine the DC charging type based on the maximum permissible total discharge voltage;

[0125] S203: Determine the required voltage value for the charging vehicle based on the maximum permissible total discharge voltage value;

[0126] S204: If the DC charging type is boost DC charging, the required voltage value is sent to the discharging vehicle so that the discharging vehicle can perform boost discharge control based on the required voltage value and buck charging control based on the real-time battery voltage of the charging vehicle.

[0127] Among them, the real-time battery voltage of the charging vehicle refers to the voltage value of the battery pack inside the charging vehicle collected in real time, which can be expressed in U... bat2 express.

[0128] As an example, in step S201, after the charging vehicle and the discharging vehicle establish a communication link, the on-board controller of the charging vehicle can receive the maximum allowable total discharge voltage value U sent by the discharging vehicle. cml_max The maximum permissible total discharge voltage value U cml_max The total voltage value can be determined based on the number of battery cells in the battery pack of the discharging vehicle, or it can be determined based on the actual voltage of the batteries in the battery pack.

[0129] As an example, in step S202, the on-board controller of the charging vehicle can set the maximum permissible total discharge voltage value U. cml_max The evaluation conditions are compared with those of a pre-set boost DC charging system, and the type of DC charging for the discharging vehicle to charge the charging vehicle is determined based on the comparison results. In this example, the maximum permissible total discharge voltage value U... cml_max When the evaluation conditions for boost DC charging are met, it can be determined that a step-up / step-down process is required when the discharging vehicle performs DC charging on the charging vehicle; therefore, its DC charging type is boost DC charging. Conversely, if the maximum permissible total discharge voltage value U is not met, the charging type is boost DC charging. cml_max If the evaluation conditions for boost DC charging are not met, it can be determined that no step-up or step-down processing is required when the discharging vehicle performs DC charging to the charging vehicle. Therefore, its DC charging type is non-boost DC charging. The evaluation conditions for boost DC charging are pre-set conditions that require boost DC charging; that is, pre-set conditions to evaluate whether boost control is needed during the discharging process of the discharging vehicle to the charging vehicle.

[0130] The required voltage value for charging vehicles refers to the voltage value that needs to be supplied to the vehicle during DC charging, which can be expressed as U. BCL express.

[0131] As an example, in step S203, the on-board controller of the charging vehicle can determine the required voltage value U of the charging vehicle based on the received maximum allowable total discharge voltage value of the discharging vehicle and a pre-set conversion relationship between the maximum allowable total discharge voltage value of the discharging vehicle and the required voltage value of the charging vehicle. BCL In this example, when the maximum permissible total discharge voltage is a dynamic value determined based on the real-time battery voltage of the vehicle being discharged, the required voltage value is also dynamically changing; when the maximum permissible total discharge voltage is a fixed value determined based on the number of battery cells in the vehicle being discharged, the required voltage value is also a fixed voltage value.

[0132] In one embodiment, the required voltage value of the charging vehicle is the difference between the maximum permissible total discharge voltage value and a fourth differential voltage threshold.

[0133] The fourth differential pressure threshold is a pre-set fourth differential pressure value used to reflect the differential pressure between the maximum allowable total discharge voltage of the discharging vehicle and the required voltage of the charging vehicle, and can be represented by b.

[0134] In this example, the charging vehicle can discharge a maximum permissible total voltage value U. cml_max The difference between the voltage and the fourth differential pressure threshold b is determined as the required voltage value U for the charging vehicle. BCL , that is U BCL =U cml_max -b. In this example, the required voltage value U for the charging vehicle. BCL The charging voltage required for DC charging of a vehicle, and the maximum permissible total discharge voltage U. cml_max The maximum discharge voltage that the discharging vehicle can achieve is specified. Normal charging can only proceed if the charging voltage required by the charging vehicle is less than the discharging voltage of the discharging vehicle. Therefore, the maximum permissible total discharge voltage U must be guaranteed. cml_max and required voltage value U BCL There is a pressure difference between them.

[0135] In one embodiment, the fourth differential voltage threshold ranges from 10V to 30V. For example, the fourth differential voltage threshold b can be, but is not limited to, values ​​such as 10V, 12V, 15V, 18V, 22V, 25V, 27V, 28V, or 30V.

[0136] In one example, at the maximum permissible total discharge voltage value U cml_max =U bat1 At time -a, due to the actual battery voltage U of the discharging vehicle... bat1 The dynamic changes mean that the discharge vehicle will display the real-time changing maximum allowable total discharge voltage value U. cml_max It is sent to the charging vehicle, which in turn will adjust the maximum permissible total discharge voltage U based on the real-time changing voltage value. cml_maxDynamically adjust the required voltage value U of the charging vehicle BCL =U cml_max -b=U bat1 -ab, so that subsequent adjustments can be made based on the required voltage value U. BCL Perform DC charging.

[0137] In another example, at the maximum permissible total discharge voltage value U cml_max When the value is set to max{U1, d*number of battery cells - e}, since the number of battery cells in the discharging vehicle is a fixed value, the total allowable discharge voltage value (d*number of battery cells - e) is also a fixed value. In this case, the charging vehicle can determine the maximum allowable total discharge voltage value U1 based on this fixed value. cml_max Adjust the required voltage value U of the charging vehicle. BCL =U cml_max -b=max{U1, d*number of battery cells-e}-b, so that subsequent voltage values ​​U can be determined based on this requirement. BCL Perform DC charging.

[0138] As an example, in step S204, the on-board controller of the charging vehicle, when the DC charging type is boost DC charging, sends the required voltage value to the discharging vehicle, so that the discharging vehicle performs boost discharge control based on the required voltage value, that is, the discharging vehicle discharges at a lower discharge voltage and then gradually increases its discharge voltage; and, while the discharging vehicle performs boost discharge control, the on-board controller of the charging vehicle also needs to perform buck charging control based on the real-time battery voltage U of the charging vehicle. bat2 The charging voltage is gradually reduced by step-down charging control. When the discharge voltage of the discharging vehicle is consistent with the charging voltage of the charging vehicle, non-boost discharge control is then implemented. At this time, DC charging can be performed based on a larger power to avoid the charging vehicle's maximum output voltage being too high, which would affect the safety of the discharging vehicle discharging to the charging vehicle.

[0139] In this embodiment, the charging vehicle communicates with the discharging vehicle and can receive the maximum allowable total discharge voltage value sent by the discharging vehicle. Based on the maximum allowable total discharge voltage value, the corresponding DC charging type and required voltage value are determined. When the DC charging type is boost DC charging, the required voltage value is sent to the discharging vehicle so that the discharging vehicle can perform boost discharge control based on the required voltage value. At the same time, the charging vehicle performs buck charging control according to the real-time battery voltage of the charging vehicle so that the discharge voltage of the discharging vehicle gradually increases while the charging voltage of the charging vehicle gradually decreases, ensuring the safety of the discharging vehicle discharging to the charging vehicle.

[0140] In one embodiment, after determining the DC charging type and the required voltage value of the charging vehicle based on the maximum permissible total discharge voltage value, the vehicle-to-vehicle charging control method further includes:

[0141] If the DC charging type is non-boost DC charging, the required voltage value is sent to the discharging vehicle so that the discharging vehicle can perform non-boost discharge control based on the required voltage value.

[0142] As an example, when the DC charging type is non-boost DC charging, the on-board controller of the charging vehicle can send the required voltage value to the discharging vehicle, so that the discharging vehicle can perform non-boost discharge control based on the required voltage value U. BCL By establishing a constant discharge voltage, discharge can be performed based on this constant voltage. When the discharging vehicle discharges to the charging vehicle, its discharge voltage remains constant, eliminating the need for voltage boosting. This simplifies the control logic and improves the efficiency of the discharging vehicle discharging to the charging vehicle.

[0143] In this embodiment, the charging vehicle communicates with the discharging vehicle and can receive the maximum allowable total discharge voltage value sent by the discharging vehicle. Based on the maximum allowable total discharge voltage value, the corresponding DC charging type and required voltage value are determined. When the DC charging type is non-boost DC charging, the required voltage value is sent to the discharging vehicle so that the discharging vehicle can perform non-boost discharge control based on the required voltage value, without the need for boost / boost control, thereby improving the efficiency of the discharging vehicle discharging to the charging vehicle.

[0144] In one embodiment, step S202, which determines the DC charging type based on the maximum permissible total discharge voltage, includes:

[0145] S2021: Obtain the maximum permissible total charging voltage value for the charging vehicle;

[0146] S022: If the maximum permissible total discharge voltage is less than the maximum permissible total charging voltage, then the DC charging type is determined to be boost DC charging; and / or,

[0147] S2023: If the maximum allowable total discharge voltage is not less than the maximum allowable total charging voltage, then the DC charging type is determined to be non-boost DC charging.

[0148] The maximum permissible total charging voltage refers to the total voltage that a charging vehicle can receive in a vehicle-to-vehicle charging scenario. In this example, if the charging voltage of the charging vehicle exceeds this maximum permissible total charging voltage, an overcharging risk is considered to exist.

[0149] As an example, in step S2021, when the on-board controller of the charging vehicle needs to evaluate the DC charging type, it can determine the maximum allowable total charging voltage value based on the battery conditions such as the number of battery cells in the battery pack or the actual voltage of the battery pack. Based on the maximum allowable total charging voltage value, the risk of overcharging during DC charging of the charging vehicle can be avoided, and the safety of DC charging of the charging vehicle by the discharging vehicle can be ensured.

[0150] In one embodiment, the maximum permissible total charging voltage of the charging vehicle is the smaller of the highest permissible total charging voltage of the charging vehicle and a second preset total voltage value.

[0151] The maximum permissible total charging voltage is the highest total voltage value that the charging vehicle can receive during the charging process, which can be expressed as U. bhm The second preset total voltage value is the pre-set total voltage value that allows charging. It is the minimum total charging voltage value for the charging vehicle and can be represented by U2.

[0152] In one embodiment, the second preset total voltage value is in the range of 600V-800V. For example, the second total charging voltage value U2 can be, but is not limited to, 600V, 620V, 660V, 688V, 712V, 740V, 750V, 765V, 778V, or 800V.

[0153] As an example, the charging vehicle can obtain the maximum permissible total charging voltage U of the charging vehicle. bhm The maximum permissible total charging voltage U bhm The maximum allowable total charging voltage U can be determined based on the number of battery cells in the battery pack of the charging vehicle, or based on the actual voltage of the batteries in the battery pack. This reflects the highest total voltage the charging vehicle can receive. Then, the charging vehicle can transmit the maximum allowable total charging voltage U. bhm It is compared with the second preset total voltage value U2 to determine the maximum allowable total charging voltage U. bhm The smaller value between the first total charging voltage value U2 and the second total charging voltage value U2 is determined as the maximum allowable total charging voltage value, i.e., the maximum allowable total charging voltage value is min{U2}. bhm The maximum allowable total charging voltage value U2 can be ensured to be no greater than the first total charging voltage value U2, so as to avoid the risk of overcharging when the charging voltage of the charging vehicle is greater than the first total charging voltage value U2, and to ensure the safety of the DC charging process from the discharging vehicle to the charging vehicle.

[0154] In this example, the on-board controller of the charging vehicle obtains the maximum allowable total charging voltage value min{U bhm After U2}, the received maximum allowable total discharge voltage value U can be obtained. cml_max With the maximum allowable total charging voltage value min{U bhm The comparison is performed between U2 and U2 to determine whether the evaluation conditions for boost DC charging are met based on the comparison results.

[0155] As an example, in step S2022, the on-board controller of the charging vehicle is at the maximum permissible total discharge voltage value U cml_max Less than the maximum allowable total charging voltage value min{U bhmWhen U2}, it can be determined that the maximum output voltage of the discharging vehicle is lower than the maximum output voltage of the charging vehicle, and the charging vehicle is determined to be a high-voltage vehicle. When the discharging vehicle discharges to the charging vehicle, the charging vehicle is at risk of overcharging, and step-up and step-down control is required to prevent the risk. Therefore, it is determined that the evaluation conditions corresponding to step-up DC charging are met, and thus, its DC charging type is determined to be step-up DC charging.

[0156] As an example, in step S2023, the on-board controller of the charging vehicle is at the maximum permissible total discharge voltage value U cml_max Not less than the maximum permissible total charging voltage value min{U bhm When U2}, it can be determined that the maximum output voltage of the discharging vehicle is higher than that of the charging vehicle, and the charging vehicle is a low-voltage vehicle. When the discharging vehicle discharges to the charging vehicle, there is no need for step-up / step-down control, and its DC charging type is determined to be non-step-up DC charging.

[0157] In this embodiment, the maximum output voltage of the discharging vehicle and the maximum allowable total discharge voltage of the charging vehicle are compared to evaluate the magnitude of their maximum output voltages. This determines whether the charging vehicle is a high-voltage vehicle or a low-voltage vehicle. For high-voltage vehicles, buck-boost control is required to prevent overcharging. For low-voltage vehicles, buck-boost control is not required, which helps improve charging efficiency.

[0158] In one embodiment, step S204, namely, performing step-down charging control based on the real-time battery voltage of the charging vehicle, includes:

[0159] S2041: If the voltage reduction target value does not reach the maximum voltage reduction value, then the charging vehicle is charged based on the voltage reduction target value, and the voltage reduction target value is reduced based on the preset voltage regulation speed to obtain an updated target voltage reduction value; and / or,

[0160] S2042: If the voltage reduction target value reaches the maximum voltage reduction value, then charge the vehicle based on the maximum voltage reduction value;

[0161] The target voltage reduction value and the maximum voltage reduction value are determined based on the real-time battery voltage and the maximum allowable total discharge voltage of the charging vehicle.

[0162] Among them, the real-time battery voltage of the charging vehicle refers to the voltage value of the battery pack inside the charging vehicle collected in real time, which can be expressed in U... bat2 The voltage reduction target value is calculated based on the real-time battery voltage of the charging vehicle, representing the target voltage reduction value that needs to be achieved at the current moment. The maximum voltage reduction value is dynamically determined based on the real-time battery voltage of the charging vehicle and the maximum allowable total discharge voltage of the discharging vehicle.

[0163] As an example, when the DC charging type is boost DC charging, the on-board controller of the charging vehicle sends the required voltage value to the discharging vehicle. This allows the discharging vehicle to perform boost discharge control based on the required voltage value, while simultaneously acquiring the real-time battery voltage U of the charging vehicle. bat2 The real-time battery voltage U is calculated using a pre-set voltage reduction target value calculation strategy. bat2 Calculations are performed to obtain the real-time battery voltage U of the charging vehicle. bat2 Matching target pressure reduction value U Buck The pre-set maximum voltage reduction calculation strategy is used to calculate the real-time battery voltage U of the charging vehicle. bat2 and the maximum permissible total discharge voltage U of the charging vehicle cml_max Calculations are performed to obtain the maximum voltage drop U that matches the battery conditions of the charging and discharging vehicles. Buck_max So that the target voltage U can be used as a basis for the reduction. Buck and the maximum voltage drop U Buck_max It performs real-time voltage reduction control on the battery voltage of the charging vehicle.

[0164] In one embodiment, the voltage reduction target value of the charging vehicle is the smaller of a first total voltage reduction value and a third preset total voltage value; the maximum voltage reduction value of the charging vehicle is the smaller of the first total voltage reduction value and the second total voltage reduction value; the first total voltage reduction value is the difference between the real-time battery voltage of the charging vehicle and a fifth differential voltage threshold; the second total voltage reduction value is the difference between the maximum allowable total discharge voltage value and the fifth differential voltage threshold.

[0165] The third preset total voltage value is the pre-set total charging voltage value, which is the minimum total charging voltage value when the vehicle is charging. It can be represented by U3. Generally speaking, the higher the third preset total voltage value U3, the shorter the voltage rise time and the better the user experience.

[0166] Among them, the real-time battery voltage of the charging vehicle refers to the voltage value of the battery pack inside the charging vehicle collected in real time, which can be expressed in U... bat2 The fifth differential pressure threshold here is a pre-set fifth differential pressure value, which can be represented by c. The value range of the fifth differential pressure threshold c is 10V-30V.

[0167] In one embodiment, the third preset total voltage value ranges from 360V to 420V; and / or, the fifth differential voltage threshold ranges from 10V to 30V.

[0168] As an example, the third preset total voltage value U3 is in the range of 360V-420V. For example, the third preset total voltage value U3 can be, but is not limited to, 360V, 375V, 378V, 390V, 395V, 399V, 412V, 218V or 420V.

[0169] As an example, the fifth differential pressure threshold ranges from 10V to 30V. For instance, the fifth differential pressure threshold c can be, but is not limited to, values ​​such as 10V, 12V, 15V, 19V, 21V, 23V, 26V, 29V, or 30V.

[0170] As an example, the onboard controller of a charging vehicle can obtain the real-time battery voltage U of the vehicle being charged. bat2 Then, the real-time battery voltage U of the charging vehicle is measured. bat2 The difference between the first voltage drop value and the fifth differential voltage threshold c is determined as the first total voltage drop value, i.e., the first total voltage drop value = U bat2 -c, where the first step-down total voltage value is the total voltage value that needs to be stepped down based on the real-time battery voltage of the charging vehicle.

[0171] As an example, the on-board controller can also determine the difference between the maximum permissible total discharge voltage of the discharging vehicle and the fifth differential voltage threshold c as the second total voltage drop value, i.e., the second total voltage drop value = U cml_max -c, the second total voltage reduction value is the total voltage value that needs to be reduced based on the maximum permissible total discharge voltage value of the discharge vehicle.

[0172] As an example, the on-board controller of the charging vehicle acquires the first step-down total voltage value U. bat2 After -c, the first total step-down voltage value U can be... bat2 The larger value between -c and the third preset total voltage U3 is determined as the voltage reduction target value U for the charging vehicle. Buck , that is U Buck =min{U bat2 -c, U3}, ensuring that its determined target voltage reduction value U Buck The voltage is greater than or equal to the third preset total voltage value U3, so that when the charging vehicle is charging, its total voltage needs to be reduced to a sufficiently small level to receive more electricity from the discharging vehicle and avoid the risk of overcharging.

[0173] As an example, the on-board controller of the charging vehicle acquires the first step-down total voltage value U corresponding to the charging vehicle. bat2 -c and the second total step-down voltage value U corresponding to the discharge vehicle cml_max After using -c, the two values ​​need to be compared to determine the larger value as the maximum voltage drop U. Buck_max , that is U Buck_max =min{U bat2 -c, U cml_max -c}, so that the maximum voltage drop U Buck_max This can be understood as the maximum voltage reduction value determined based on the actual conditions of the discharging and charging vehicles.

[0174] As an example, in step S2041, the on-board controller of the charging vehicle sets the voltage reduction target value U. Buck The maximum voltage drop U was not reached. Buck_max The system first charges the battery pack of the charging vehicle based on the voltage reduction target value. After each charge, the voltage reduction target value is reduced based on the preset voltage regulation rate ΔU / s to obtain the updated target voltage reduction value. This ensures that the updated target voltage reduction value gradually decreases, so that it corresponds to the voltage boost control of the discharging vehicle, thus ensuring the safety of charging the charging vehicle.

[0175] As an example, in step S2042, the on-board controller of the charging vehicle sets the voltage reduction target value U. Buck Reaching the maximum voltage drop U Buck_max At this moment, the U of the charging vehicle Buck =U cml_max -c, U Buck_max =U cml_max -c, U Buck =U Buck_max It can be determined that the discharge voltage of the discharging vehicle is basically the same as the charging voltage of the charging vehicle. At this time, the battery pack of the charging vehicle is charged based on the maximum voltage drop, so that DC charging can be performed based on a larger constant power in the future, thus ensuring the charging efficiency of the charging vehicle.

[0176] In this embodiment, the real-time battery voltage of the charging vehicle and the maximum allowable total discharge voltage of the discharging vehicle are respectively compared with the fifth voltage difference threshold to calculate the first total voltage drop value corresponding to the charging vehicle and the second total voltage drop value corresponding to the discharging vehicle. Then, based on the first and second total voltage drop values, the voltage drop target value and the maximum voltage drop value of the charging vehicle are determined. Based on the comparison results of the two, it is determined whether voltage reduction control is needed. This enables voltage reduction processing during the boost DC charging process, preventing overcharging of the charging vehicle and helping to improve charging efficiency.

[0177] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0178] In one embodiment, an on-board controller is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the vehicle-to-vehicle charging control method described in the above embodiment, for example... Figure 1 As shown in S101-S103, or Figure 2 S201-S204 shown will not be described again here to avoid repetition.

[0179] In one embodiment, a vehicle is provided, including the on-board controller described in the above embodiments. This on-board controller is capable of executing the vehicle-to-vehicle charging control method described in the above embodiments, for example... Figure 1 As shown in S101-S103, or Figure 2 S201-S204 shown will not be described again here to avoid repetition. The vehicle in this embodiment can be a discharging vehicle or a charging vehicle.

[0180] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When executed by a processor, the computer program implements the vehicle-to-vehicle charging control method described in the above embodiment, for example... Figure 1 As shown in S101-S103, or Figure 2 S201-S204 shown will not be described again here to avoid repetition.

[0181] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0182] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0183] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A vehicle-to-vehicle charging control method, characterized in that, include: Obtain the maximum permissible total discharge voltage value of the discharging vehicle and send the maximum permissible total discharge voltage value to the charging vehicle; The maximum permissible total discharge voltage value refers to the total voltage value that the discharging vehicle is allowed to discharge to the charging vehicle. The system receives the DC charging type and required voltage value determined by the charging vehicle based on the maximum permissible total discharge voltage value; the required voltage value refers to the voltage value that needs to be used to charge the charging vehicle during the DC charging process. If the DC charging type is boost DC charging, the discharging vehicle performs boost discharge control based on the required voltage value, and the charging vehicle performs buck charging control based on the real-time battery voltage.

2. The vehicle-to-vehicle charging control method as described in claim 1, characterized in that, The maximum permissible total discharge voltage value is the difference between the actual battery voltage of the discharge vehicle and the first differential voltage threshold.

3. The vehicle-to-vehicle charging control method as described in claim 2, characterized in that, The first differential pressure threshold ranges from 10V to 30V.

4. The vehicle-to-vehicle charging control method as described in claim 1, characterized in that, The maximum allowable total discharge voltage value is the larger of the battery's allowable total discharge voltage value and the first preset total voltage value; The battery's allowable total discharge voltage value is the difference between the battery's lower limit discharge total voltage value and the second differential voltage threshold. The total lower discharge voltage of the battery is the product of the number of battery cells in the discharging vehicle and the lower discharge voltage of a single battery cell.

5. The method as described in claim 4, characterized in that, The first preset total voltage value ranges from 400V to 550V; and / or, The lower limit discharge voltage of the single battery cell is in the range of 3V-3.2V; and / or, The second differential pressure threshold ranges from 10V to 30V.

6. The vehicle-to-vehicle charging control method as described in claim 1, characterized in that, The boost discharge control based on the required voltage value includes: If the target voltage value of the discharging vehicle does not reach the required voltage value, then the charging vehicle is discharged based on the first current and the target voltage value, and the target voltage value is boosted based on a preset voltage regulation rate to obtain an updated target voltage value; and / or If the target voltage value of the discharging vehicle reaches the required voltage value, then the required voltage value is determined as the target voltage value, and the charging vehicle is discharged based on the second current and the target voltage value, while monitoring the current SOC value of the discharging vehicle; when the current SOC value is less than the preset SOC value, the discharge to the charging vehicle is stopped. The second current is greater than the first current.

7. The vehicle-to-vehicle charging control method as described in claim 6, characterized in that, The first current ranges from 10A to 50A; and / or, The value range of the second current is 100A-125A.

8. The vehicle-to-vehicle charging control method as described in claim 1, characterized in that, After receiving the DC charging type and required voltage value determined by the charging vehicle based on the maximum permissible total discharge voltage value, the vehicle-to-vehicle charging control method further includes: If the DC charging type is non-boost DC charging, then non-boost discharge control is performed based on the required voltage value.

9. The vehicle-to-vehicle charging control method as described in claim 8, characterized in that, The non-boost discharge control based on the required voltage value includes: Discharge is performed based on the third current and target voltage value, and the current SOC value is monitored. When the current SOC value is less than the preset SOC value, the discharge to the charging vehicle is stopped. The target voltage value is the difference between the required voltage value and the third differential voltage threshold.

10. The vehicle-to-vehicle charging control method as described in claim 9, characterized in that, The value range of the third current is 100A-125A, and / or, The value range of the third differential pressure threshold is 10V-30V.

11. A vehicle-to-vehicle charging control method, characterized in that, include: Receive the maximum permissible total discharge voltage value sent by the discharge vehicle; The maximum permissible total discharge voltage value refers to the total voltage value that the discharging vehicle is allowed to discharge to the charging vehicle. The DC charging type is determined based on the maximum permissible total discharge voltage value; The required voltage value for the charging vehicle is determined based on the maximum permissible total discharge voltage value. The required voltage value refers to the voltage value that needs to be used to charge the vehicle during the DC charging process. If the DC charging type is boost DC charging, the required voltage value is sent to the discharging vehicle so that the discharging vehicle performs boost discharge control based on the required voltage value, and the charging vehicle performs buck charging control based on the real-time battery voltage of the charging vehicle.

12. The vehicle-to-vehicle charging control method as described in claim 11, characterized in that, The vehicle-to-vehicle charging control method also includes: If the DC charging type is non-boost DC charging, the required voltage value is sent to the discharging vehicle so that the discharging vehicle can perform non-boost discharge control based on the required voltage value.

13. The vehicle-to-vehicle charging control method as described in claim 11, characterized in that, The step of determining the DC charging type based on the maximum permissible total discharge voltage value includes: Obtain the maximum permissible total charging voltage value for the charging vehicle; If the maximum permissible total discharge voltage is less than the maximum permissible total charging voltage, then the DC charging type is determined to be boost DC charging; and / or If the maximum allowable total discharge voltage is not less than the maximum allowable total charging voltage, then the DC charging type is determined to be non-boost DC charging.

14. The vehicle-to-vehicle charging control method as described in claim 13, characterized in that, The maximum permissible total charging voltage of the charging vehicle is the smaller of the highest permissible total charging voltage of the charging vehicle and the second preset total voltage value.

15. The method as described in claim 14, characterized in that, The second preset total voltage value ranges from 600V to 800V.

16. The vehicle-to-vehicle charging control method as described in claim 11, characterized in that, The required voltage value of the charging vehicle is the difference between the maximum allowable total discharge voltage value and the fourth differential voltage threshold.

17. The method as described in claim 16, characterized in that, The fourth differential pressure threshold value ranges from 10V to 30V.

18. The vehicle-to-vehicle charging control method as described in claim 11, characterized in that, The step-down charging control based on the real-time battery voltage of the charging vehicle includes: If the voltage reduction target value is not reached, the charging vehicle is charged based on the voltage reduction target value, and the voltage reduction target value is processed based on a preset voltage regulation rate to obtain an updated target voltage reduction value; and / or If the voltage reduction target value reaches the maximum voltage reduction value, then the charging vehicle is charged based on the maximum voltage reduction value; The target voltage reduction value and the maximum voltage reduction value are determined based on the real-time battery voltage of the charging vehicle and the maximum allowable total discharge voltage value.

19. The vehicle-to-vehicle charging control method as described in claim 18, characterized in that, The voltage reduction target value of the charging vehicle is the smaller value between the first total voltage reduction value and the third preset total voltage value; The maximum voltage drop of the charging vehicle is the smaller of the first total voltage drop value and the second total voltage drop value; The first total voltage drop value is the difference between the real-time battery voltage of the charging vehicle and the fifth differential voltage threshold. The second total voltage drop value is the difference between the maximum allowable total discharge voltage value and the fifth differential voltage threshold.

20. The method as described in claim 19, characterized in that, The value of the third preset total voltage is in the range of 360V-420V; and / or The fifth differential pressure threshold value ranges from 10V to 30V.

21. An on-board controller, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the vehicle-to-vehicle charging control method as described in any one of claims 1 to 20.

22. A vehicle, characterized in that, Includes the vehicle controller as described in claim 21.

23. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the vehicle-to-vehicle charging control method as described in any one of claims 1 to 20.

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