Vehicle control method and device, vehicle and computer readable storage medium

Abstract

The invention provides a vehicle control method and device, a vehicle and a computer readable storage medium, and relates to the technical field of vehicles, the method is applied to the vehicle comprising a power battery and a plurality of motors, the working states of the motors comprise a driving state and a recycling state, when the working state of the motors is the driving state, the power battery supplies power to the motors, and when the recycling state of the motors is the driving state, the power battery supplies power to the motors. When the working state of the motor is a recovery state, the motor charges the power battery; the method comprises the following steps: when a vehicle runs, if a power battery of the vehicle is over-discharged, reducing the absolute value of the output torque of a motor in a driving state so as to solve the problem of over-discharge of the power battery; and if the power battery of the vehicle is overcharged, the absolute value of the output torque of the motor in the recovery state is reduced, so that the problem of overcharging of the power battery is solved, the power battery can be recovered to a safe and reliable working state from an abnormal state within a short time, and the driving safety and the running stability of the vehicle are improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and more particularly, to a vehicle control method, device, vehicle, and computer-readable storage medium in the field of vehicle technology. Background Art

[0002] Battery overdischarge occurs when a battery is discharged below the manufacturer's specified minimum voltage level or minimum safe charge percentage. Battery overcharge occurs when a battery is charged above the manufacturer's specified maximum voltage level or maximum safe charge percentage. During vehicle operation, the power battery, as a core component for energy storage and power supply, has a direct impact on the vehicle's safety, power performance, and range. Overdischarge or overcharge of a power battery can pose a series of safety risks. For example, battery voltage exceeding the safe range can degrade cell performance and even increase the risk of thermal runaway. Furthermore, the battery management system may misjudge battery status, affecting the accuracy of the vehicle's energy allocation strategy. Furthermore, prolonged overdischarge or overcharge can accelerate battery aging, shorten service life, and, in severe cases, even cause safety accidents. Therefore, ensuring that the power battery remains within a safe and reliable operating range during vehicle operation has become a critical issue that needs to be addressed. Summary of the Invention

[0003] Embodiments of the present application provide a vehicle control method, device, vehicle, and computer-readable storage medium. During vehicle driving, if the vehicle's power battery is over-discharged, the absolute value of the output torque of the motor in the driving state is reduced to solve the problem of power battery over-discharge; if the vehicle's power battery is overcharged, the absolute value of the output torque of the motor in the recovery state is reduced to solve the problem of power battery overcharge. This allows the power battery to recover from an abnormal state to a safe and reliable working state in a short time, which is beneficial to improving the safety and operational stability of the vehicle.

[0004] In a first aspect, a vehicle control method is provided, which includes a power battery and multiple motors, and the working states of the motors include a driving state and a recovery state. When the working state of the motor is the driving state, the power battery supplies power to the motor, and when the working state of the motor is the recovery state, the motor charges the power battery; the vehicle control method includes: when the power battery is in an abnormal state, obtaining the working states of the multiple motors, the abnormal state being an over-discharge state or an overcharge state; determining a target motor from the multiple motors according to the abnormal state and the working state, when the abnormal state is the over-discharge state, the target motor is the motor whose working state is the driving state among the multiple motors, and when the abnormal state is the overcharge state, the target motor is the motor whose working state is the recovery state among the multiple motors; and reducing the absolute value of the output torque of at least one of the target motors to make the power battery out of the abnormal state.

[0005] The vehicle control method provided in the present application can promptly eliminate the problem of power battery over-discharge by reducing the absolute value of the output torque of the motor in the driving state among multiple motors when the vehicle's power battery is in an over-discharge state, because the main cause of the power battery over-discharge is caused by the motor in the driving state; and can promptly eliminate the problem of power battery over-charge by reducing the absolute value of the output torque of the motor in the recovery state among multiple motors when the vehicle's power battery is in an over-charge state, because the main cause of the power battery over-charge is caused by the motor in the recovery state. In this way, the problem of power battery over-discharge or over-charge is solved, and the power battery can be restored from an abnormal state to a safe and reliable working state in a short time, which is conducive to improving the safety of vehicle driving.

[0006] In one possible implementation, reducing the absolute value of the output torque of at least one of the target motors includes: obtaining the high-voltage end power of multiple motors and the remaining battery power of the power battery, wherein, when the power battery is in a discharging state, the remaining battery power is the remaining available driving power, and when the power battery is in a charging state, the remaining battery power is the remaining available recovery power; based on the high-voltage end power of multiple motors and the remaining battery power, reducing the absolute value of the output torque of at least one of the target motors.

[0007] If the power battery is in an over-discharge state, the absolute value of the output torque of at least one of the target motors is dynamically reduced based on the high-voltage terminal power of the multiple motors and the remaining available driving power of the power battery to remove the power battery from the over-discharge state, thereby preventing the power battery from over-discharging. If the power battery is in an over-charge state, the absolute value of the output torque of at least one of the target motors is dynamically reduced based on the high-voltage terminal power of the multiple motors and the remaining available regenerative power of the power battery to remove the power battery from the over-charge state, thereby preventing the power battery from over-charging.

[0008] In one possible implementation, reducing the absolute value of the output torque of at least one of the target motors based on the high-voltage end power of multiple motors and the remaining battery power includes: determining the difference between the remaining battery power and the total power to obtain the target excess power, where the total power is the sum of the high-voltage end powers of the multiple motors; sorting the individual motors in the target motors according to the order of motor efficiency to obtain a first sorting result, where when the power battery is in a discharging state, the motor efficiency order is the motor discharge efficiency from small to large, and when the power battery is in a charging state, the motor efficiency order is the motor feedback efficiency from large to small; reducing the absolute value of the output torque of at least one of the target motors based on the target excess power and the first sorting result.

[0009] In the event of battery overdischarge, the absolute value of the output torque of the motor with the lowest discharge efficiency is prioritized, followed by the motor with the next lowest, and so on. While from the perspective of high-voltage power, reducing the power of any motor in the event of battery overdischarge has the same impact on the battery—meaning both can alleviate or even eliminate the battery overdischarge problem—because the discharge efficiencies of the motors in the first ranking result vary, if the high-voltage power reduction of these motors in the first ranking result is the same, the output torque of the motor with the lowest discharge efficiency will be reduced less than that of the motor with the highest discharge efficiency. Therefore, prioritizing the absolute value of the output torque of the motor with the lowest discharge efficiency in the first ranking result not only mitigates or even eliminates battery overdischarge, but also minimizes the impact on the vehicle's drive torque, thereby maintaining the stability of the vehicle's power output. In the event of battery overcharge, the absolute value of the output torque of the motor with the highest feedback efficiency is prioritized, followed by the motor with the next highest, and so on. Although from the perspective of high-voltage end power, reducing the power of any motor has the same impact on the power battery when the power battery is overcharged, that is, both can alleviate the power battery overcharge problem or even eliminate the overcharge problem, but because the feedback efficiency of the motors in the first sorting result is different, if the absolute value of the power reduction of the high-voltage end power of these motors in the first sorting result is the same, the output torque of the motor with high feedback efficiency will be reduced less than that of the motor with low feedback efficiency. Therefore, prioritizing the reduction of the absolute value of the output torque of the motor with the highest feedback efficiency in the first sorting result can more quickly get the power battery out of the overcharge state, thereby ensuring that the power battery overcharge problem is resolved in a short time.

[0010] In one possible implementation, reducing the absolute value of the output torque of at least one of the target motors according to the target excess power and the first sorting result includes: taking the first motor in the first sorting result as the motor to be adjusted; comparing the target power value with the absolute value of the high-voltage end power of the motor to be adjusted, the target power value being the absolute value of the target excess power; if the target power value is less than or equal to the absolute value of the high-voltage end power of the motor to be adjusted, determining the corrected output power of the motor to be adjusted according to the target power value, and reducing the absolute value of the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted; if the target power value is greater than the absolute value of the high-voltage end power of the motor to be adjusted, taking the high-voltage end power of the motor to be adjusted as the corrected output power of the motor to be adjusted, and reducing the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted. The absolute value of the output torque is obtained, and the motor to be adjusted is deleted from the first sorting result to obtain a second sorting result; the difference between the target power value and the absolute value of the high-voltage end power of the motor to be adjusted is used as the target power value, and the second sorting result is used as the first sorting result, and the step of taking the first motor in the first sorting result as the motor to be adjusted is executed until the target power value is less than or equal to the absolute value of the high-voltage end power of a motor in the first sorting result, so as to adjust the output torque of each motor in the target motor one by one, that is, after adjusting the output torque of one of the motors, if the power battery still cannot be out of the abnormal state, the output torque of the next motor is adjusted, and so on. Dynamic intervention and protection of the power battery state is achieved, which is beneficial to improving the reliability and safety of the power battery operation.

[0011] In one possible implementation, reducing the absolute value of the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted includes: obtaining the corrected output torque corresponding to the corrected output power of the motor to be adjusted; subtracting the absolute value of the requested torque of the motor to be adjusted from the absolute value of the corrected output torque to obtain the target torque; and controlling the motor to be adjusted to output the target torque.

[0012] In one possible implementation, when the power battery is in an abnormal state, the vehicle control method further includes: timing the time the power battery is in the abnormal state to obtain a timing duration; after the absolute values ​​of the output torques of all motors in the target motors are reduced, the vehicle control method further includes: if the timing duration is greater than or equal to the second duration and less than the first duration, increasing the absolute value of the target excess power; using the target excess power after the absolute value is increased as the target excess power, and executing the step of using the first motor in the first sorting result as the motor to be adjusted. By increasing the absolute value of the target excess power, the absolute value of the output torque of each motor in the target motor can be further reduced, thereby ensuring that the power battery is out of the abnormal state.

[0013] In one possible implementation, increasing the absolute value of the target excess power includes: determining a first preset power corresponding to the battery driving power of the power battery and the vehicle speed as the reserve power, or determining a second preset power corresponding to the battery recovery power of the power battery and the vehicle speed as the reserve power; adding the absolute value of the reserve power to the absolute value of the target excess power to obtain the target excess power with the increased absolute value, thereby realizing dynamic determination of the reserve power based on the vehicle speed, thereby ensuring that the power battery accurately exits the abnormal state.

[0014] In a second aspect, a vehicle control device is provided. The vehicle includes a power battery and multiple motors. The motors have operating states including a driving state and a recovery state. When the motors are in the driving state, the power battery supplies power to the motors. When the motors are in the recovery state, the motors charge the power battery. The vehicle control device includes:

[0015] A status acquisition module is used to obtain the working status of multiple motors when the power battery is in an abnormal state, where the abnormal state is an over-discharge state or an over-charge state;

[0016] a motor selection module, configured to determine a target motor from among multiple motors based on an abnormal state and a working state. When the abnormal state is an over-discharge state, the target motor is a motor in a driving state among the multiple motors. When the abnormal state is an over-charge state, the target motor is a motor in a recovery state among the multiple motors.

[0017] The torque adjustment module is used to reduce the absolute value of the output torque of at least one of the target motors to make the power battery out of the abnormal state.

[0018] In a third aspect, a vehicle is provided, comprising a memory and a processor. The memory is configured to store executable program code, and the processor is configured to retrieve and execute the executable program code from the memory, so that the vehicle executes the vehicle control method of the first aspect or any possible implementation of the first aspect.

[0019] In a fourth aspect, a computer program product is provided, which includes: computer program code, which, when running on a computer, enables the computer to execute the vehicle control method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0020] In a fifth aspect, a computer-readable storage medium is provided, which stores a computer program code. When the computer program code runs on a computer, the computer executes the vehicle control method in the above-mentioned first aspect or any possible implementation of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic flow chart of a vehicle control method provided in an embodiment of the present application is shown;

[0022] Figure 2 shows an architectural diagram of a hybrid vehicle;

[0023] Figure 3 A schematic diagram showing battery power and motor speed when the motor is in driving mode;

[0024] Figure 4 A schematic structural diagram of a vehicle control device provided in an embodiment of the present application is shown;

[0025] Figure 5 A structural schematic diagram of a vehicle provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0026] The following will clearly and thoroughly describe the technical solutions in this application in conjunction with the accompanying drawings. In the description of the embodiments of this application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more than two.

[0027] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0028] Battery overdischarge refers to the discharge of a battery below the minimum voltage level or minimum safe charge percentage specified by the manufacturer, while battery overcharge refers to the charging of a battery above the maximum voltage level or maximum safe charge percentage specified by the manufacturer. During vehicle operation, the power battery, as a core component for energy storage and power supply, has a direct impact on the safety, power performance, and endurance of the vehicle. When a power battery is overdischarged or overcharged, it may cause a series of safety hazards. For example, if the battery voltage exceeds the safe range, it may cause the performance of the battery cell to deteriorate and even increase the risk of thermal runaway. At the same time, the battery management system may affect the accuracy of the vehicle's energy distribution strategy due to misjudgment of the battery status. In addition, if the power battery is in an overdischarged or overcharged state for a long time, it may accelerate battery aging, shorten its service life, and even cause safety accidents in severe cases.

[0029] Embodiments of the present application provide a vehicle control method, device, vehicle, and computer-readable storage medium. During vehicle driving, if the vehicle's power battery is over-discharged, the absolute value of the output torque of the motor in the driving state is reduced to solve the problem of power battery over-discharge; if the vehicle's power battery is overcharged, the absolute value of the output torque of the motor in the recovery state is reduced to solve the problem of power battery overcharge. This allows the power battery to recover from an abnormal state to a safe and reliable working state in a short time, which is beneficial to improving the safety and operational stability of the vehicle.

[0030] The following is an embodiment of a vehicle control method provided in this application specification.

[0031] Figure 1 A schematic flow chart of a vehicle control method provided in an embodiment of the present application is shown. Figure 1 As shown, the vehicle control method provided by the embodiment of the present application is applied to a vehicle, which is specifically a hybrid vehicle. The hybrid vehicle includes a power battery and multiple motors. The working states of the motors include a driving state and a recovery state. When the working state of the motors is the driving state, the power battery supplies power to the motors. When the working state of the motors is the recovery state, the motors charge the power battery. Figure 2 As shown, Figure 2 The diagram shows the architecture of a hybrid vehicle, which includes a front axle, a rear axle, and multiple motors, including a first motor, a second motor, and a third motor. One of the front axle and the rear axle is referred to as the first axle, and the other is referred to as the second axle. The first axle is equipped with the first motor, the second motor, an engine, and a transmission, while the second axle is equipped with the third motor. The first motor is a GM motor (Generator Motor), the second motor is a TM motor (Traction Motor), and the third motor is a P4 motor (Rear Axle Motor). The first motor is mechanically connected to the engine, the engine is mechanically connected to the transmission, and the second motor is mechanically connected to the transmission. The first, second, and third motors are all electrically connected to the power battery.

[0032] When the first motor is used as a generator, the engine drives the first motor to rotate, thereby charging the power battery; when the first motor is used as a drive motor, it assists the engine in driving the vehicle, improving power performance, and can also serve as a starter to start the engine. The second motor drives the wheels through the gearbox, and the third motor is independently installed on an axle (such as the rear axle) and can independently drive the wheels of the axle on which it is located. The operating states of the first, second, and third motors include a driving state and a recovery state. In the driving state, the torque output by each motor is positive torque. When the first motor is in the driving state, it may start the engine or assist the engine in driving the vehicle; when the second motor is in the driving state, it drives the wheels through the gearbox, and when the third motor is in the driving state, it drives the wheels of the axle on which it is located. In the recovery state, the torque output by each motor is negative torque, which can achieve energy recovery and convert mechanical energy into electrical energy to charge the power battery. Among them, during the period when the engine drives the first motor to rotate to charge the power battery, the operating state of the first motor can be understood as a recovery state.

[0033] The vehicle control method provided in the embodiment of the present application includes the following steps:

[0034] S110: When the power battery is in an abnormal state, obtain the operating states of the plurality of motors.

[0035] In an exemplary embodiment, the abnormal state is an over-discharge state or an over-charge state. During the driving of the vehicle, if the power battery is determined to be in an abnormal state, the power battery is allowed to escape (eliminate) the abnormal state by reducing the absolute value of the motor output torque within a certain monitoring time. Among them, the monitoring time is less than the set alarm time, that is, the present application is intended to determine that the power battery is in an abnormal state, and before the duration of the abnormal state reaches the alarm time, the power battery is allowed to escape the abnormal state, so that the power battery does not meet the alarm condition, that is, the vehicle will not issue a fault alarm for the power battery, so it can be considered that the power battery has not failed. Alternatively, it can also be understood that after the power battery becomes abnormal (over-discharged or overcharged), the power battery is restored to normal within a short period of time, so that the power battery does not meet the alarm condition, that is, the vehicle will not issue a fault alarm for the power battery, so it can be considered that the power battery has not failed.

[0036] When the power battery is in an abnormal state, the operating states of the multiple motors are obtained. The operating states of the multiple motors may be the same, or partially the same and partially different. For example, the operating states of the multiple motors may all be in the driving state, or the operating state of one motor may be in the recovery state while the other motors are all in the driving state, and so on.

[0037] S120: Determine a target motor from a plurality of motors according to the abnormal state and the operating state.

[0038] After obtaining the operating states of each of the multiple motors, a target motor is determined from the multiple motors based on the abnormal state and the operating state. The target motor includes at least one of the multiple motors. Specifically, when the abnormal state is an over-discharge state, the target motor is a motor in the multiple motors that is in a driving state. For example, the multiple motors include first to third motors. If the operating states of the first and third motors are in a driving state, then the first and third motors are both target motors. If the operating states of the multiple motors are all in a driving state, then the multiple motors are all target motors, and so on. When the abnormal state is an overcharge state, the target motor is a motor in the multiple motors that is in a recovery state. For example, if the operating states of the first and third motors are in a recovery state, then the first and third motors are both target motors. If the operating states of the multiple motors are all in a recovery state, then the multiple motors are all target motors, and so on.

[0039] S130: Reducing the absolute value of the output torque of at least one of the target motors to remove the power battery from the abnormal state.

[0040] In the case where the power battery is in an over-discharge state (i.e., the battery is over-discharged), the target motors determined are all motors in a driving state, because the main cause of the power battery over-discharge is caused by the motor in the driving state. Therefore, the absolute value of the output torque of at least one of the target motors is directly reduced to make the power battery out of the over-discharge state. In the case where the power battery is in an overcharge state (i.e., the battery is overcharged), the target motors determined are all motors in a recovery state, because the cause of the power battery over-discharge is caused by the motor in the recovery state. Therefore, the absolute value of the output torque of at least one of the target motors is directly reduced to make the power battery out of the overcharge state. Among them, whether the power battery is in an over-discharge state or an overcharge state, if the absolute value of the output torque of one of the target motors is reduced and the power battery cannot be out of the abnormal state, the absolute value of the output torque of another motor will continue to be reduced until the absolute values ​​of the output torque of all the target motors are reduced.

[0041] The vehicle control method provided in the present application can promptly eliminate the problem of power battery over-discharge by reducing the absolute value of the output torque of the motor in the driving state among multiple motors when the vehicle's power battery is in an over-discharge state, because the main cause of the power battery over-discharge is caused by the motor in the driving state; and can promptly eliminate the problem of power battery over-charge by reducing the absolute value of the output torque of the motor in the recovery state among multiple motors when the vehicle's power battery is in an over-charge state, because the main cause of the power battery over-charge is caused by the motor in the recovery state. In this way, the problem of power battery over-discharge or over-charge is solved, and the power battery can be restored from an abnormal state to a safe and reliable working state in a short time, which is conducive to improving the safety of vehicle driving.

[0042] In one possible implementation, reducing the absolute value of the output torque of at least one of the target motors includes the following steps:

[0043] Obtain the high-voltage end power of multiple motors and the remaining power of the power battery;

[0044] The absolute value of the output torque of at least one of the target motors is reduced according to the high-voltage end power of the plurality of motors and the remaining power of the battery.

[0045] The calculation method of the high-voltage end power is related to the working state of the motor. The high-voltage end power of the motor in the driving state is calculated by formula (1), and the high-voltage end power of the motor in the recovery state is calculated by formula (2), as follows:

[0046] P1=P2×η1 (1)

[0047] P1=P2 / η2 (2)

[0048] P1=(T×n) / 9550 (3)

[0049] Where P1 represents the motor's mechanical power, P2 represents the motor's high-voltage power, η1 represents the motor's discharge efficiency, η2 represents the motor's feedback efficiency, T represents the motor's output torque, n represents the motor's speed, and 9550 represents the unit conversion constant.

[0050] The remaining battery power of the power battery is related to the specific abnormal state of the power battery. When the power battery is in a discharging state, the remaining battery power is the remaining available driving power. When the power battery is in a charging state, the remaining battery power is the remaining available recovery power.

[0051] The remaining available driving power and the remaining available regenerative power are calculated by the vehicle control unit (VCU). The specific calculation formula is as follows:

[0052] H1=G1-X-Y-Z-W (4)

[0053] H2=G2-X-Y-Z-W (5)

[0054] Wherein, H1 represents the remaining available driving power, G1 represents the battery driving power, X represents the power consumption of the DC-DC converter, Y represents the power consumption of the PTC (Positive Temperature Coefficient) heater, Z represents the high-voltage bus loss power, W represents the power consumption of the compressor, H2 represents the remaining available recovery power, G2 represents the battery recovery power, and the battery recovery power and the remaining available recovery power are both less than or equal to 0. In formulas (4) and (5), all powers except the battery recovery power and the remaining available recovery power are greater than or equal to 0. The unit of power mentioned in the embodiments of the present application is kW.

[0055] If the power battery is in an over-discharge state, the absolute value of the output torque of at least one of the target motors is dynamically reduced based on the high-voltage terminal power of the multiple motors and the remaining available driving power of the power battery to remove the power battery from the over-discharge state, thereby preventing the power battery from over-discharging. If the power battery is in an over-charge state, the absolute value of the output torque of at least one of the target motors is dynamically reduced based on the high-voltage terminal power of the multiple motors and the remaining available regenerative power of the power battery to remove the power battery from the over-charge state, thereby preventing the power battery from over-charging.

[0056] In one possible implementation, reducing the absolute value of the output torque of at least one of the target motors based on the high-voltage end power of the multiple motors and the remaining battery power includes the following steps:

[0057] Determine the difference between the remaining battery power and the total power to obtain the target excess power. The total power is the sum of the high-voltage end powers of multiple motors.

[0058] Sorting each motor in the target motor according to the order of motor efficiency to obtain a first sorting result;

[0059] According to the target excess power and the first sorting result, the absolute value of the output torque of at least one of the target motors is reduced.

[0060] When the power battery is discharged, the remaining battery power is the remaining available driving power, denoted as H1. The high-voltage terminal power of the first motor is denoted as A1, the high-voltage terminal power of the second motor is denoted as B1, the high-voltage terminal power of the third motor is denoted as C1, the target excess power is denoted as E1, and the total power is denoted as D1. Therefore, D1 = A1 + B1 + C1, and E1 = H1 - D1. When the power battery is charged, the remaining battery power is the remaining available regenerative power, denoted as H2. The high-voltage terminal power of the first motor is denoted as A2, the high-voltage terminal power of the second motor is denoted as B2, the high-voltage terminal power of the third motor is denoted as C2, the target excess power is denoted as E2, and the total power is denoted as D2. Therefore, D2 = A2 + B2 + C2, and E2 = H2 - D2.

[0061] The motor efficiency order is related to the charge and discharge state of the power battery. When the power battery is in the discharge state, the motor efficiency order is the order from small to large motor discharge efficiency. Then, the motors in the target motors are sorted according to the motor efficiency order. In the first sorting result, the motor with small motor discharge efficiency is before the motor with large motor discharge efficiency. For example, the target motors include the first to third motors, and the motor discharge efficiency of the third motor is < the motor discharge efficiency of the second motor < the motor discharge efficiency of the first motor. Then the first sorting result is: third motor - second motor - first motor.

[0062] When the power battery is in a charging state, the motor efficiency order is the order from large to small motor feedback efficiency. Then, each motor in the target motor is sorted according to the motor efficiency order. In the first sorting result, the motor with large motor feedback efficiency is before the motor with small motor feedback efficiency. For example, the target motor includes the first to third motors, and the motor feedback efficiency of the third motor is less than the motor feedback efficiency of the second motor, which is less than the motor feedback efficiency of the first motor. Then, the first sorting result is: first motor - second motor - third motor.

[0063] After obtaining the target excess power and the first ranking result, the absolute value of the output torque of at least one of the target motors is reduced based on the target excess power and the first ranking result. In the event of power battery overdischarge, the absolute value of the output torque of the motor with the lowest discharge efficiency is preferentially reduced, followed by the motor with the next lowest discharge efficiency, and so on. Although from the perspective of high-voltage end power, reducing the power of any motor in the event of power battery overdischarge has the same impact on the power battery, i.e., both can alleviate or even eliminate the overdischarge problem, the motors in the first ranking result have different discharge efficiencies. If the high-voltage end power reduction of these motors in the first ranking result is the same, the output torque of the motor with the lowest discharge efficiency will be reduced less than that of the motor with the higher discharge efficiency. Therefore, prioritizing the reduction of the absolute value of the output torque of the motor with the lowest discharge efficiency in the first ranking result not only alleviates or even eliminates power battery overdischarge, but also minimizes the impact on the vehicle's drive torque, thereby maintaining the smoothness of the vehicle's power output. In the case of overcharging of the power battery, the absolute value of the output torque of the motor with the highest motor feedback efficiency will be reduced first, followed by the second highest, and so on. Although from the perspective of high-voltage end power, in the case of overcharging of the power battery, reducing the power of any motor has the same effect on the power battery, that is, both can alleviate the power battery overcharging problem or even eliminate the overcharging problem, but because the feedback efficiencies of these motors in the first sorting result are different, if the absolute value of the power reduction of the high-voltage end power of these motors in the first sorting result is the same, the torque reduction of the output torque of the motor with high feedback efficiency is smaller than that of the motor with low feedback efficiency. Therefore, giving priority to reducing the absolute value of the output torque of the motor with the highest feedback efficiency in the first sorting result can make the power battery out of the overcharge state more quickly, thereby ensuring that the overcharge problem of the power battery is solved in a short time.

[0064] In a possible implementation, reducing the absolute value of the output torque of at least one of the target motors according to the target excess power and the first ranking result includes the following steps:

[0065] The first motor in the first sorting result is used as the motor to be adjusted;

[0066] Compare the target power value with the absolute value of the high-voltage end power of the motor to be adjusted, where the target power value is the absolute value of the target excess power;

[0067] If the target power value is less than or equal to the absolute value of the high-voltage end power of the motor to be adjusted, determining the corrected output power of the motor to be adjusted according to the target power value, and reducing the absolute value of the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted;

[0068] If the target power value is greater than the absolute value of the high-voltage end power of the motor to be adjusted, the high-voltage end power of the motor to be adjusted is used as the corrected output power of the motor to be adjusted, the absolute value of the output torque of the motor to be adjusted is reduced based on the corrected output power of the motor to be adjusted, and the motor to be adjusted is deleted from the first sorting result to obtain a second sorting result;

[0069] Then, the difference between the target power value and the absolute value of the high-voltage end power of the motor to be adjusted is used as the target power value, and the second sorting result is used as the first sorting result, and the step of using the first motor in the first sorting result as the motor to be adjusted is executed until the target power value is less than or equal to the absolute value of the high-voltage end power of a motor in the first sorting result.

[0070] Among them, reducing the absolute value of the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted includes: obtaining the corrected output torque corresponding to the corrected output power of the motor to be adjusted, subtracting the absolute value of the requested torque of the motor to be adjusted from the absolute value of the corrected output torque to obtain the target torque, and controlling the motor to be adjusted to output the target torque.

[0071] The following describes a process of reducing the absolute value of the output torque of at least one of the target motors according to the target excess power and the first sorting result, taking the multiple motors including the first motor, the second motor and the third motor as an example.

[0072] If the power battery is over-discharged, the target power value is represented by |E1|, and the remaining battery power is the remaining available drive power, represented by H1. Assuming the first sorting result is: third motor - second motor - first motor, the first, second, and third motors in the first sorting result are the third motor, the second motor, and the first motor, respectively. When the power battery is discharged, the high-voltage terminal power of the first through third motors is positive.

[0073] The third motor (ie, the first motor) in the first sorting result is used as the motor to be adjusted, and then |E1| is compared with |C1| to obtain a first comparison result, and the corrected output power of the third motor is expressed as K3.

[0074] If the first comparison result indicates |E1|≤|C1|, that is, H1-(D1-|E1|)≥0, it can be obtained, indicating that the power battery can be out of the over-discharge state after only reducing the absolute value of the output torque of the third motor. In this case, K3=|E1| is set, and then the absolute value of the output torque of the third motor is reduced based on K3=|E1|. The whole process ends here.

[0075] If the first comparison result indicates |E1|>|C1|, which means that the power battery still cannot escape the over-discharge state after only reducing the absolute value of the output torque of the third motor, then K3=C1 is set, that is, not only the absolute value of the output torque of the third motor needs to be reduced based on K3=C1, but the absolute value of the output torque of the second motor also needs to be further reduced, and the process continues to execute.

[0076] The process of reducing the absolute value of the output torque of the third motor based on K3 is as follows: K3 is converted using the above formula (3) to obtain the corrected output torque corresponding to K3; then, the absolute value of the requested torque of the third motor is subtracted from the absolute value of the corrected output torque to obtain the third target torque of the third motor; and then, the third target torque is used to control the third motor, i.e., to control the third motor to output the third target torque, thereby reducing the absolute value of the output torque of the third motor. When the power battery is in an over-discharge state, each motor in the target motor is in a driving state, the requested torque of the third motor is positive, and the obtained third target torque is also positive.

[0077] Next, the third motor is deleted from the first sorting result to obtain the second sorting result. The second sorting result is: second motor - first motor, and then (|E1|-|C1|) is used as |E1|, that is, the new |E1| (also known as |E1|'), |E1|'=(|E1|-|C1|), and the second sorting result is used as the first sorting result, that is, the second sorting result is the new first sorting result, and the step of using the first motor in the first sorting result as the motor to be adjusted is re-executed.

[0078] The first motor in the new first sorting result (second sorting result) is the second motor. Therefore, the motor to be adjusted is the second motor. Then, (|E1| - |C1|) is compared with |B1| to obtain the second comparison result, and the corrected output power of the second motor is expressed as K2.

[0079] If the second comparison result indicates that (|E1|-|C1|)≤|B1|, it can be obtained that H1-(D1-(|E1|-|C1|))≥0, which means that after reducing the absolute value of the output torque of the third motor and then reducing the absolute value of the output torque of the second motor, the power battery can be out of the over-discharge state. Then set K2=(|E1|-|C1|), and then reduce the absolute value of the output torque of the second motor based on K2=(|E1|-|C1|). The whole process ends here.

[0080] The process of reducing the absolute value of the output torque of the second motor based on K2 is as follows: K2 is converted using the above formula (3) to obtain the corrected output torque corresponding to K2, and then the absolute value of the requested torque of the second motor is subtracted from the absolute value of the corrected output torque to obtain the second target torque of the second motor. The second target torque is then used to control the second motor, i.e., the second motor is controlled to output the second target torque, thereby reducing the absolute value of the output torque of the second motor. When the power battery is in an over-discharge state, each motor in the target motor is in a driving state, the requested torque of the second motor is a positive torque, and the obtained second target torque is also a positive torque.

[0081] If the second comparison result indicates that (|E1|-|C1|)>|B1|, it means that after only reducing the absolute value of the output torque of the third motor and reducing the absolute value of the output torque of the second motor, the power battery still cannot escape the over-discharge state, then set K2=B1, that is, not only the absolute value of the output torque of the second motor needs to be reduced based on K2=B1, but the absolute value of the output torque of the first motor also needs to be further reduced, and the process continues to execute.

[0082] Next, the second motor is deleted from the new first sorting result (second sorting result) to obtain a new second sorting result, called the third sorting result. The third sorting result is the first motor, and then (|E1|-|C1|-|B1|) is used as |E1|, that is, the latest |E1| (also known as |E1|"), |E1|"=(|E1|-|C1|-|B1|), and the third sorting result is used as the first sorting result, that is, the third sorting result is the latest first sorting result, and the step of taking the first motor in the first sorting result as the motor to be adjusted is re-executed.

[0083] The first motor in the third sorting result is the first motor, so the motor to be adjusted is the first motor. Then, (|E1| - |C1| - |B1|) is compared with |A1| to obtain a third comparison result, and the corrected output power of the first motor is expressed as K1.

[0084] If the third comparison result indicates that (|E1|-|C1|-|B1|)≤|A1|, it can be obtained that H1-(D1-(|E1|-|C1|-|B1|))≥0, which means that after reducing the absolute value of the output torque of the second motor and then reducing the absolute value of the output torque of the first motor, the power battery can be out of the over-discharge state. Then set K1=(|E1|-|C1|-|B1|), and then reduce the absolute value of the output torque of the first motor based on K1=(|E1|-|C1|-|B1|). The whole process ends here.

[0085] The process of reducing the absolute value of the output torque of the first motor based on K1 is as follows: K1 is converted using the above formula (3) to obtain the corrected output torque corresponding to K1, and then the absolute value of the requested torque of the first motor is subtracted from the absolute value of the corrected output torque to obtain the first target torque of the first motor. The first target torque is then used to control the first motor, i.e., to control the first motor to output the first target torque, thereby reducing the absolute value of the output torque of the first motor. When the power battery is in an overcharged state, each motor in the target motor is in a driving state, the requested torque of the first motor is a negative torque, and the obtained first target torque is also a negative torque.

[0086] If the third comparison result indicates (|E1| - |C1| - |B1|) > |A1|, indicating that even after reducing the absolute values ​​of the output torques of the third motor, the second motor, and the first motor, the power battery still cannot escape the over-discharge state, the original |E1| needs to be increased, and the increased original |E1| is used as the current |E1|. The step of selecting the first motor in the first sorting result as the motor to be adjusted is then repeated until the power battery escapes the over-discharge state, and the process ends. When re-executing the step of selecting the first motor in the first sorting result as the motor to be adjusted, the first sorting result includes all motors in the target motor group.

[0087] Alternatively, after obtaining the third sorting result, the first motor in the third sorting result is the first motor, then the motor to be adjusted is the first motor, and then (|E1|-|C1|-|B1|) is set to K1, and the absolute value of the output torque of the first motor is reduced based on K1=(|E1|-|C1|-|B1|). If the power battery still cannot escape the over-discharge state after reducing the absolute value of the output torque of the first motor, the original |E1| is increased, and the increased original |E1| is used as the |E1|, and the step of using the first motor in the first sorting result as the motor to be adjusted is re-executed to adjust the output torque of each motor in the target motor one by one. That is, after adjusting the output torque of one of the motors, if the power battery still cannot escape the over-discharge state, the output torque of the next motor is adjusted, and so on. Dynamic intervention and protection of the power battery state is achieved, which is beneficial to improving the reliability and safety of the power battery operation.

[0088] It is worth noting that when the power battery is in an over-discharge state, each motor in the target motor is in a driving state, the remaining available driving power of the power battery, the power and torque related to each motor in the target motor are all positive values, and the target excess power can be called the driving excess power.

[0089] There are multiple ways to determine whether a power battery is in an over-discharge state. For example, if E1 ≥ 0, it indicates that the power battery is not in an over-discharge state. If E1 < 0, it indicates that the power battery is in an over-discharge state. For another example, if G1 < I1 × U1, it indicates that the power battery is in an over-discharge state. If G1 ≥ I1 × U1, it indicates that the power battery is not in an over-discharge state. I1 represents the output current of the power battery, which is a positive value, and U1 represents the output voltage of the power battery.

[0090] When the power battery is overcharged, the target power value is represented by |E2|, and the remaining battery power is the remaining available regenerative power, represented by H2. Assuming the first sorting result is: third motor - second motor - first motor, the first, second, and third motors in the first sorting result are the third motor, the second motor, and the first motor, respectively. When the power battery is charged, the high-voltage terminal power of the first through third motors is negative.

[0091] The third motor (ie, the first motor) in the first sorting result is used as the motor to be adjusted, and then |E2| is compared with |C2| to obtain a first comparison result. The corrected output power of the third motor is expressed as K3.

[0092] If the first comparison result indicates |E2|≤|C2|, that is, H2-(D2-|E2|)≥0, it can be obtained, indicating that the power battery can be out of the overcharge state after only reducing the absolute value of the output torque of the third motor. In this case, K3=-|E2| is set, and then the absolute value of the output torque of the third motor is reduced based on K3=-|E2|. The whole process ends here.

[0093] If the first comparison result indicates |E2|>|C2|, which means that the power battery still cannot escape the overcharge state after only reducing the absolute value of the output torque of the third motor, then K3=C2 is set, that is, not only the absolute value of the output torque of the third motor needs to be reduced based on K3=C2, but the absolute value of the output torque of the second motor also needs to be further reduced, and the process continues to execute.

[0094] The process of reducing the absolute value of the output torque of the third motor based on K3 is as follows: K3 is converted using the above formula (3) to obtain the corrected output torque corresponding to K3; then, the absolute value of the requested torque of the third motor is subtracted from the absolute value of the corrected output torque to obtain the third target torque of the third motor; and then, the third target torque is used to control the third motor, i.e., to control the third motor to output the third target torque, thereby reducing the absolute value of the output torque of the third motor. When the power battery is in an overcharged state, each motor in the target motor is in a recovery state, the requested torque of the third motor is negative, and the obtained third target torque is also negative.

[0095] Next, delete the third motor from the first sorting result to obtain the second sorting result. The second sorting result is: second motor - first motor, and then use (|E2|-|C2|) as |E2|, that is, the new |E2| (also known as |E2|'), |E2|'=(|E2|-|C2|), and use the second sorting result as the first sorting result, that is, the second sorting result is the new first sorting result, and re-execute the step of using the first motor in the first sorting result as the motor to be adjusted.

[0096] The first motor in the new first sorting result (second sorting result) is the second motor. Therefore, the motor to be adjusted is the second motor. Then, (|E2| - |C2|) is compared with |B2| to obtain the second comparison result, and the corrected output power of the second motor is expressed as K2.

[0097] If the second comparison result indicates that (|E2|-|C2|)≤|B2|, it can be obtained that H2-(D2-(|E2|-|C2|))≥0, which means that after reducing the absolute value of the output torque of the third motor and then reducing the absolute value of the output torque of the second motor, the power battery can be out of the overcharge state. Then set K2=-(|E2|-|C2|), and then reduce the absolute value of the output torque of the second motor based on K2=-(|E2|-|C2|). The whole process ends here.

[0098] The process of reducing the absolute value of the output torque of the second motor based on K2 is as follows: K2 is converted using the above formula (3) to obtain the corrected output torque corresponding to K2, and then the absolute value of the requested torque of the second motor is subtracted from the absolute value of the corrected output torque to obtain the second target torque of the second motor. The second target torque is then used to control the second motor, i.e., to control the second motor to output the second target torque, thereby reducing the absolute value of the output torque of the second motor. When the power battery is in an overcharged state, each motor in the target motor is in a recovery state, the requested torque of the second motor is negative, and the obtained second target torque is also negative.

[0099] If the second comparison result indicates that (|E2|-|C2|)>|B2|, it means that after only reducing the absolute value of the output torque of the third motor and reducing the absolute value of the output torque of the second motor, the power battery still cannot escape the overcharge state, then set K2=B2, that is, not only the absolute value of the output torque of the second motor needs to be reduced based on K2=B2, but the absolute value of the output torque of the first motor also needs to be further reduced, and the process continues to execute.

[0100] Next, the second motor is deleted from the new first sorting result (second sorting result) to obtain a new second sorting result, called the third sorting result. The third sorting result is the first motor, and then (|E2|-|C2|-|B2|) is used as |E2|, that is, the latest |E2| (also known as |E2|"), |E2|" = (|E2|-|C2|-|B2|), and the third sorting result is used as the first sorting result, that is, the third sorting result is the latest first sorting result, and the step of taking the first motor in the first sorting result as the motor to be adjusted is re-executed.

[0101] The first motor in the third sorting result is the first motor, so the motor to be adjusted is the first motor. Then, (|E2| - |C2| - |B2|) is compared with |A2| to obtain a third comparison result, and the corrected output power of the first motor is expressed as K1.

[0102] If the third comparison result indicates that (|E2|-|C2|-|B2|)≤|A2|, it can be obtained that H2-(D2-(|E2|-|C2|-|B2|))≥0, which means that after reducing the absolute value of the output torque of the second motor and then reducing the absolute value of the output torque of the first motor, the power battery can be out of the overcharge state. Then set K1=-(|E2|-|C2|-|B2|), and then reduce the absolute value of the output torque of the first motor based on K1=-(|E2|-|C2|-|B2|). The whole process ends here.

[0103] The process of reducing the absolute value of the output torque of the first motor based on K1 is as follows: K1 is converted using the above formula (3) to obtain the corrected output torque corresponding to K1, and then the absolute value of the requested torque of the first motor is subtracted from the absolute value of the corrected output torque to obtain the first target torque of the first motor. The first target torque is then used to control the first motor, that is, to control the first motor to output the first target torque, thereby reducing the absolute value of the output torque of the first motor. When the power battery is in an overcharged state, each motor in the target motor is in a recovery state, the requested torque of the first motor is negative, and the obtained first target torque is also negative.

[0104] If the third comparison result indicates (|E2| - |C2| - |B2|) > |A2|, indicating that the power battery still cannot escape the overcharge state after reducing the absolute values ​​of the output torques of the third motor, the second motor, and the first motor, the original |E2| needs to be increased, and the increased original |E2| is used as the current |E2|. The step of selecting the first motor in the first sorting result as the motor to be adjusted is then repeated until the power battery escapes the overcharge state, and the process ends. When the step of selecting the first motor in the first sorting result as the motor to be adjusted is repeated, the first sorting result includes all motors in the target motor group.

[0105] Alternatively, after obtaining the third sorting result, the first motor in the third sorting result is the first motor, then the motor to be adjusted is the first motor, and then -(|E2|-|C2|-|B2|) is set to K1, and the absolute value of the output torque of the first motor is reduced based on K1=-(|E2|-|C2|-|B2|). If the power battery still cannot escape the overcharge state after the absolute value of the output torque of the first motor is reduced, the original |E2| is increased, and the increased original |E2| is used as the |E2|, and the step of setting the first motor in the first sorting result as the motor to be adjusted is re-executed to adjust the output torque of each motor in the target motor one by one. That is, if the power battery still cannot escape the overcharge state after adjusting the output torque of one of the motors, the output torque of the next motor is adjusted, and so on. Dynamic intervention and protection of the power battery state is achieved, which is beneficial to improving the reliability and safety of the power battery operation.

[0106] It is worth noting that when the power battery is in an overcharged state, each motor in the target motor is in a recovery state, the remaining available recovery power of the power battery, the power and torque related to each motor in the target motor are all negative values, and the target excess power can be called the recovery excess power.

[0107] There are multiple ways to determine whether the power battery is overcharged. For example, if E2 > 0, it indicates that the power battery is overcharged; if E2 ≤ 0, it indicates that the power battery is not overcharged. For another example, if G2 ≤ ​​I2 × U2, it indicates that the power battery is not overcharged; if G2 > I2 × U2, it indicates that the power battery is overcharged. I2 represents the charging current of the power battery, which is a negative value, and U2 represents the charging voltage of the power battery.

[0108] In one possible implementation, when the power battery is in an abnormal state, the vehicle control method further includes the following steps:

[0109] The time during which the power battery is in an abnormal state is measured to obtain the measured duration;

[0110] After the absolute values ​​of the output torques of all the target motors are reduced, if the power battery is still in an abnormal state, the vehicle control method further includes the following steps:

[0111] If the timing duration is greater than or equal to the second duration and less than the first duration, increase the absolute value of the target excess power, use the target excess power after the absolute value is increased as the target excess power, and execute the step of using the first motor in the first sorting result as the motor to be adjusted.

[0112] When it is determined that the battery is in an abnormal state, the timer is started to count the time the power battery is in the abnormal state to obtain the timing duration. The timer specifically starts counting from zero. The first duration is the above-mentioned alarm duration, and the second duration is the above-mentioned maximum duration allowed to execute S110-S130.

[0113] After completing the step of reducing the absolute value of the output torque of at least one of the target motors according to the target excess power and the first sorting result, so as to reduce the absolute values ​​of the output torque of all the target motors, if the power battery is still in an abnormal state, and the timing duration of the timer is greater than or equal to the second duration (T2) and less than the first duration (T1), indicating that after reducing the absolute value of the output torque of each motor in the target motor, the power battery still cannot be freed from the abnormal state, the absolute value of the target excess power is increased, and the target excess power after the absolute value is increased is used as the target excess power, and then the step of using the first motor in the first sorting result as the motor to be adjusted is executed. In this way, by increasing the absolute value of the target excess power, the absolute value of the output torque of each motor in the target motor can be further reduced, thereby ensuring that the power battery is freed from the abnormal state.

[0114] Among them, after the power battery leaves the abnormal state, the timer starts to decrease until it is reset to zero. For example, the current timer is 10s, and then the timer starts counting down from 10s. When the countdown reaches 0, it is re-determined whether the power battery is in an abnormal state, that is, it waits for 10 seconds before re-determining whether the power battery is in an abnormal state. By adopting a mechanism that delays a certain period of time before re-determining whether the power battery is in an abnormal state after the power battery leaves the abnormal state (i.e., returns to a normal discharge state or a normal charging state), the system avoids premature intervention to re-determine whether the power battery is in an abnormal state, which may cause a jump in the power battery output power, thereby improving the stability of the power battery operation.

[0115] After re-determining whether the power battery is in an abnormal state, if the power battery is still in an abnormal state, the timer is started to count the time length of the power battery in the abnormal state, and S110-S130 are re-executed. After re-execution of S110-S130, if the power battery is still in an abnormal state and the timing time length is greater than or equal to the second time length and less than the first time length, the absolute value of the target excess power is increased again, and the target excess power after the absolute value is increased is used as the target excess power. Then, the first motor in the first sorting result is used as the motor to be adjusted until the difference between the target power value and the absolute value of the high-voltage end power of the motor to be adjusted is used as the target power value, and the second sorting result is used as the first sorting result. The first motor in the first sorting result is used as the motor to be adjusted, until the target power value is less than or equal to the absolute value of the high-voltage end power of a motor in the first sorting result, and the cycle is repeated.

[0116] It is worth noting that for motors that are not included in the target motors, the control of the motors that are not included in the target motors will not be intervened. For example, if the target motors do not include the first motor, the control of the first motor will not be intervened, such as keeping the control of the first motor unchanged, or setting the corrected output power of the first motor to 0. In this way, the absolute value of the output torque of the first motor is reduced to 0, that is, the control of the first motor remains unchanged.

[0117] In one possible implementation, increasing the absolute value of the target excess power includes the following steps:

[0118] Determining a first preset power corresponding to the battery driving power of the power battery and the vehicle speed as the reserve power, or determining a second preset power corresponding to the battery recovery power of the power battery and the vehicle speed as the reserve power;

[0119] The absolute value of the reserve power is added to the absolute value of the target excess power to obtain the target excess power with an increased absolute value.

[0120] In order to prevent the power battery from being unable to escape the abnormal state after the absolute value of the output torque of each motor in the driving state or the recovery state is reduced, a reserve power is set, which is expressed as CD, that is:

[0121] H1=G1-X-Y-Z-W-CD (6)

[0122] H2=G2-X-Y-Z-W-CD (7)

[0123] The reserve power is a positive value or 0.

[0124] A first mapping relationship is constructed in advance for the case of power battery discharge. The first mapping relationship includes multiple first data groups and first preset powers corresponding to each of the multiple first data groups. Each first data group includes the battery driving power of the power battery and a vehicle speed. Similarly, a second mapping relationship is also constructed for the case of power battery charging. The second mapping relationship includes multiple second data groups and second preset powers corresponding to each of the multiple second data groups. Each second data group includes the battery recovery power of the power battery and a vehicle speed. Both the first preset power and the second preset power are positive values.

[0125] If the power battery is in an over-discharged state, the vehicle's current speed is obtained, and then a first mapping relationship is queried using the current speed and battery drive power to obtain a first preset power corresponding to the current speed and battery drive power, and the first preset power corresponding to the current speed and battery drive power is determined as the reserve power. If the power battery is in an overcharged state, the vehicle's current speed is obtained, and then a second mapping relationship is queried using the current speed and battery recovery power to obtain a second preset power corresponding to the current speed and battery recovery power, and the second preset power corresponding to the current speed and battery recovery power is determined as the reserve power. After obtaining the reserve power, the absolute value of the reserve power is added to the absolute value of the target excess power to obtain the target excess power with the increased absolute value. This achieves dynamic determination of the reserve power based on vehicle speed, thereby ensuring that the power battery accurately exits the abnormal state.

[0126] The following describes a process for controlling a power battery to escape from an over-discharge state when the power battery is in an over-discharge state.

[0127] In the case where the multiple motors include a first motor, a second motor, and a third motor, if the power battery is in an over-discharge state, the vehicle control method includes the following steps:

[0128] S210: When the vehicle is traveling, if the power battery is in an over-discharge state, obtaining the operating states of the first motor, the second motor, and the third motor, and timing the time the power battery is in the over-discharge state to obtain a timing duration;

[0129] S211: Determine a motor whose working state is a driving state among the first motor, the second motor, and the third motor as a target motor;

[0130] S212: Sort each motor in the target motor based on the motor discharge efficiency from small to large to obtain a sorting result;

[0131] S213: When the ranking result is the third motor, the second motor, and the first motor, comparing the first target power value with the absolute value of the high-voltage end power of the third motor, where the first target power value is the absolute value of the excess driving power, the excess driving power is the difference between the remaining available driving power of the power battery and the total power, and the total power is the sum of the high-voltage end powers of the first motor, the second motor, and the third motor;

[0132] S214: If the first target power value is less than or equal to the absolute value of the high-voltage end power of the third motor, the first target power value is used as the corrected output power of the third motor, and the absolute value of the output torque of the third motor is reduced according to the corrected output power of the third motor. The process ends.

[0133] S215: If the first target power value is greater than the absolute value of the high-voltage end power of the third motor, the high-voltage end power of the third motor is used as the corrected output power of the third motor, and the absolute value of the output torque of the third motor is reduced according to the corrected output power of the third motor, and then S216 is executed;

[0134] S216: Determine the difference between the first target power value and the absolute value of the high-voltage end power of the third motor to obtain a second target power value;

[0135] S217: Comparing the second target power value with the absolute value of the high-voltage end power of the second motor;

[0136] S218: If the second target power value is less than or equal to the absolute value of the high-voltage end power of the second motor, the second target power value is used as the corrected output power of the second motor, and the absolute value of the output torque of the second motor is reduced according to the corrected output power of the second motor. The process ends.

[0137] S219: If the second target power value is greater than the absolute value of the high-voltage end power of the second motor, the high-voltage end power of the second motor is used as the corrected output power of the second motor, and the absolute value of the output torque of the second motor is reduced according to the corrected output power of the second motor, and S220 is executed.

[0138] S220: Determine a difference between the second target power value and the absolute value of the high-voltage end power of the second motor to obtain a third target power value;

[0139] S221: Using the second target power value as the corrected output power of the first motor, and reducing the absolute value of the output torque of the first motor according to the corrected output power of the first motor;

[0140] S222: While the absolute value of the output torque of the first motor is reduced according to the corrected output power of the first motor, if the power battery is still in an over-discharge state and the timed duration is greater than or equal to the second duration and less than the first duration, determining a first preset power corresponding to the battery driving power of the power battery and the vehicle speed as the first reserve power;

[0141] S223: Add the absolute value of the first reserve power to the absolute value of the driving excess power to obtain the driving excess power with an increased absolute value, use the driving excess power with an increased absolute value as the driving excess power, and return to S210.

[0142] During vehicle driving, if the present application detects that the vehicle's power battery is over-discharged, the absolute value of the output torque of the motor in the driving state is reduced, so that the power battery can be restored from the over-discharge state to a safe and reliable working state in a short time, thereby solving the problem of power battery over-discharge and helping to improve the safety and operational stability of the vehicle.

[0143] The following describes a process for controlling the power battery to escape from the overcharge state when the power battery is in the overcharge state.

[0144] In the case where the plurality of motors include a first motor, a second motor, and a third motor, if the power battery is in an overcharged state, the vehicle control method includes the following steps:

[0145] S310: When the vehicle is traveling, if the power battery is in an overcharged state, obtaining the operating states of the first motor, the second motor, and the third motor, and timing the time the power battery is in the overcharged state to obtain a timing duration;

[0146] S311: Determine the motor whose working state is in the recovery state among the first motor, the second motor, and the third motor as the target motor;

[0147] S312: Sort each motor in the target motor based on the motor feedback efficiency from large to small to obtain a sorting result;

[0148] S313: When the ranking result is the third motor, the second motor, and the first motor, based on the first ranking result, comparing a first target power value with the absolute value of the high-voltage end power of the third motor, where the first target power value is the absolute value of the excess recovery power, the excess recovery power is the difference between the remaining available recovery power of the power battery and the total power, and the total power is the sum of the high-voltage end powers of the first motor, the second motor, and the third motor.

[0149] S314: If the first target power value is less than or equal to the absolute value of the high-voltage end power of the third motor, the negative value of the first target power value is used as the corrected output power of the third motor, and the absolute value of the output torque of the third motor is reduced according to the corrected output power of the third motor. The process ends.

[0150] S315: If the first target power value is greater than the absolute value of the high-voltage end power of the third motor, the high-voltage end power of the third motor is used as the corrected output power of the third motor, and the absolute value of the output torque of the third motor is reduced according to the corrected output power of the third motor, and then S316 is executed.

[0151] S316: Determine the difference between the first target power value and the absolute value of the high-voltage end power of the third motor to obtain a second target power value;

[0152] S317: Compare the second target power value with the absolute value of the high-voltage end power of the second motor;

[0153] S318: If the second target power value is less than or equal to the absolute value of the high-voltage end power of the second motor, the negative value of the second target power value is used as the corrected output power of the second motor, and the absolute value of the output torque of the second motor is reduced according to the corrected output power of the second motor. The process ends.

[0154] S319: If the second target power value is greater than the absolute value of the high-voltage end power of the second motor, the high-voltage end power of the second motor is used as the corrected output power of the second motor, and the absolute value of the output torque of the second motor is reduced according to the corrected output power of the second motor, and S320 is executed.

[0155] S320: Determine a difference between the second target power value and the absolute value of the high-voltage end power of the second motor to obtain a third target power value;

[0156] S321: Using the negative value of the second target power value as the corrected output power of the first motor, and reducing the absolute value of the output torque of the first motor according to the corrected output power of the first motor;

[0157] S322: While the absolute value of the output torque of the first motor is reduced according to the corrected output power of the first motor, if the power battery is still in an overcharged state and the timed duration is greater than or equal to the second duration and less than the first duration, determining a second preset power corresponding to the battery regeneration power of the power battery and the vehicle speed as the second reserve power;

[0158] S323: Add the absolute value of the second reserve power to the absolute value of the excess recovery power to obtain the excess recovery power with an increased absolute value, use the excess recovery power with an increased absolute value as the excess recovery power, and return to S310.

[0159] During vehicle driving, if the present application detects that the vehicle's power battery is overcharged, the absolute value of the output torque of the motor in the recovery state is reduced, so that the power battery can be restored from the overcharged state to a safe and reliable working state in a short time, thereby solving the problem of power battery overcharge and improving the safety and operational stability of the vehicle.

[0160] Over-discharge of the power battery will cause the power battery to be in an undervoltage state, and over-charging of the power battery will cause the power battery to be in an overvoltage state. At present, when managing the energy of the vehicle, in order to avoid damage to the power battery due to undervoltage or overvoltage, the current solution is to reserve power when the vehicle's motor is in the driving state or the recovery state to avoid overshoot of the actual output power of the power battery. Figure 3 As shown, Figure 3 A schematic diagram showing battery power and motor speed when the motor is in driving mode is shown. Figure 3 The horizontal axis is the motor speed, and the vertical axis is the battery power, measured in kW. L1 represents the discharge power of the power battery (i.e., the power output of the power battery when the motor is in drive mode), and L2 represents the ideal allowable power of the power battery (i.e., the maximum allowable discharge power). The ideal allowable power is set to ensure that the power battery does not over-discharge. When the motor is operating, this effectively limits the maximum output power of the motor, ensuring that the actual power is always lower than the available capacity of the power battery. The so-called reserved power is the interval between L1 and L2.

[0161] While reserving power can prevent overshoot in the actual power output of the power battery, it can affect the vehicle's dynamic performance, especially during dynamic operation (such as non-uniform speed driving or frequent accelerator pedal changes). Due to factors such as CAN signal delays, active motor vibration reduction, and torque and speed filtering, the reserved power needs to be further increased to prevent overshoot. The greater the reserved power, the greater the impact on vehicle dynamics, resulting in a significant decrease in vehicle dynamics.

[0162] By adopting the vehicle control method provided by the present application, if the power battery of the vehicle is over-discharged during driving, the absolute value of the output torque of the motor in the driving state is reduced, thereby solving the problem of power battery undervoltage caused by over-discharge of the power battery. Figure 3 As shown, Figure 3L3 in the figure represents the ideal allowable power of the power battery after adopting the vehicle control method provided by this application. Through L3, it can be seen that as the motor speed increases, the actual output power of the power battery gradually increases and then coincides with L1 (to be precise, L3 fluctuates on both sides of L1), thereby maximizing the available capacity of the power battery and avoiding affecting the vehicle's power performance during driving. If the original target excess power is updated using the sum of the absolute value of the reserve power and the absolute value of the target excess power, a power gap will also appear between L1 and L3. This power gap is smaller than the power gap between L1 and L2, equivalent to the power gap between L1 and L2, and has little effect on the vehicle's power performance.

[0163] The following are device embodiments of the present application, which can be used to implement the method embodiments of the present application. For details not disclosed in the device embodiments of the present application, please refer to the method embodiments of the present application.

[0164] Figure 4 A schematic diagram of the structure of a vehicle control device provided in an embodiment of the present application is shown in FIG. Figure 4 As shown, the vehicle includes a power battery and multiple motors. The working states of the motors include a driving state and a recovery state. When the motors are in the driving state, the power battery supplies power to the motors. When the motors are in the recovery state, the motors charge the power battery. The vehicle control device 400 includes:

[0165] The state acquisition module 410 is used to acquire the operating states of the multiple motors when the power battery is in an abnormal state, where the abnormal state is an over-discharge state or an over-charge state;

[0166] a motor selection module 420 for determining a target motor from the plurality of motors based on the abnormal state and the working state; when the abnormal state is an over-discharge state, the target motor is a motor in a driving state among the plurality of motors; and when the abnormal state is an over-charge state, the target motor is a motor in a recovery state among the plurality of motors;

[0167] The torque adjustment module 430 is configured to reduce the absolute value of the output torque of at least one of the target motors to remove the power battery from an abnormal state.

[0168] In one possible implementation, the torque adjustment module 430 includes:

[0169] an acquisition unit, configured to acquire the high-voltage terminal power of the plurality of motors and the remaining battery power of the power battery, wherein when the power battery is in a discharging state, the remaining battery power is the remaining available driving power, and when the power battery is in a charging state, the remaining battery power is the remaining available recovery power;

[0170] The adjustment unit is used to reduce the absolute value of the output torque of at least one of the target motors according to the high-voltage end power of the multiple motors and the remaining power of the battery.

[0171] In one possible implementation, the adjustment unit includes:

[0172] A calculation subunit is used to determine the difference between the remaining battery power and the total power to obtain the target excess power. The total power is the sum of the high-voltage end powers of multiple motors.

[0173] a sorting subunit, configured to sort each motor in the target motor according to motor efficiency to obtain a first sorting result, wherein when the power battery is in a discharging state, the motor efficiency is sorted from small to large in terms of motor discharge efficiency, and when the power battery is in a charging state, the motor efficiency is sorted from large to small in terms of motor feedback efficiency;

[0174] The adjusting subunit is configured to reduce the absolute value of the output torque of at least one of the target motors according to the target excess power and the first sorting result.

[0175] In one possible implementation, the adjustment subunit is specifically used to take the first motor in the first sorting result as the motor to be adjusted; compare the target power value with the absolute value of the high-voltage end power of the motor to be adjusted, the target power value being the absolute value of the target excess power; if the target power value is less than or equal to the absolute value of the high-voltage end power of the motor to be adjusted, determine the corrected output power of the motor to be adjusted according to the target power value, and reduce the absolute value of the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted; if the target power value is greater than the absolute value of the high-voltage end power of the motor to be adjusted, take the high-voltage end power of the motor to be adjusted as the corrected output power of the motor to be adjusted, reduce the absolute value of the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted, and delete the motor to be adjusted from the first sorting result to obtain a second sorting result; then take the difference between the target power value and the absolute value of the high-voltage end power of the motor to be adjusted as the target power value, and take the second sorting result as the first sorting result, and execute the step of taking the first motor in the first sorting result as the motor to be adjusted until the target power value is less than or equal to the absolute value of the high-voltage end power of a motor in the first sorting result.

[0176] In one possible implementation, the adjustment subunit is specifically used to obtain the corrected output torque corresponding to the corrected output power of the motor to be adjusted; subtract the absolute value of the requested torque of the motor to be adjusted from the absolute value of the corrected output torque to obtain the target torque; and control the motor to be adjusted to output the target torque.

[0177] In a possible implementation, the vehicle control device 400 further includes:

[0178] a timing unit, for timing the time the power battery is in the abnormal state to obtain a timing duration when the power battery is in the abnormal state;

[0179] A circulation unit is used to increase the absolute value of the target excess power after the absolute values ​​of the output torques of all motors in the target motor are reduced, if the timing duration is greater than or equal to the second duration and less than the first duration; use the target excess power after the absolute value is increased as the target excess power, and execute the step of using the first motor in the first sorting result as the motor to be adjusted.

[0180] In one possible implementation, the circulation unit is specifically used to determine a first preset power corresponding to the battery driving power of the power battery and the vehicle speed as the reserve power, or to determine a second preset power corresponding to the battery recovery power of the power battery and the vehicle speed as the reserve power; and to add the absolute value of the reserve power to the absolute value of the target excess power to obtain the target excess power with the increased absolute value.

[0181] It should be noted that the vehicle control device provided in the above embodiment, when executing the vehicle control method, is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the vehicle control device provided in the above embodiment and the vehicle control method embodiment are of the same concept. Therefore, for details not disclosed in the device embodiment of this application, please refer to the above embodiment of the vehicle control method of this application, and no further details will be given here.

[0182] The serial numbers of the above embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0183] Figure 5 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application is shown. Figure 5 As shown, the vehicle 500 includes: a memory 501 and a processor 502, wherein the memory 501 stores an executable program code 5011, and the processor 502 is used to call and execute the executable program code 5011 to perform a vehicle control method.

[0184] This embodiment can divide the vehicle into functional modules based on the above-described method example. For example, each functional module can be mapped to a specific function, or two or more functions can be integrated into a single processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used.

[0185] In the case of dividing the functional modules into corresponding functional modules, the vehicle may include: a state acquisition module, a motor selection module, a torque adjustment module, etc. It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module and will not be repeated here.

[0186] The vehicle provided in this embodiment is used to execute the above-mentioned vehicle control method, and thus can achieve the same effect as the above-mentioned implementation method.

[0187] In the case of an integrated unit, the vehicle may include a processing module and a storage module. The processing module may be used to control and manage the vehicle's movements, while the storage module may be used to support the vehicle's execution of relevant program codes and data.

[0188] The processing module may be a processor or controller that implements or executes the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processing system (DSP) and a microprocessor, and the storage module may be a memory.

[0189] This embodiment also provides a computer-readable storage medium, which stores computer program code. When the computer program code runs on a computer, the computer executes the above-mentioned related method steps to implement a vehicle control method in the above-mentioned embodiment.

[0190] This embodiment further provides a computer program product. When the computer program product is run on a computer, it enables the computer to execute the above-mentioned related steps to implement a vehicle control method in the above-mentioned embodiment.

[0191] In addition, the vehicle provided in the embodiments of the present application can specifically be a chip, component or module, and the vehicle may include a connected processor and memory; wherein the memory is used to store instructions, and when the vehicle is running, the processor can call and execute instructions to enable the chip to execute a vehicle control method in the above embodiment.

[0192] Among them, the vehicle, computer-readable storage medium, computer program product or chip provided in this embodiment are all used to execute the corresponding vehicle control method provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding vehicle control method provided above, and will not be repeated here.

[0193] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0194] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0195] The above content is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A vehicle control method, characterized in that: The vehicle includes a power battery and a plurality of motors, wherein the working states of the motors include a driving state and a recovery state. When the working state of the motors is the driving state, the power battery supplies power to the motors, and when the working state of the motors is the recovery state, the motors charge the power battery. The vehicle control method includes: When the power battery is in an abnormal state, obtaining the operating states of the multiple motors, wherein the abnormal state is an over-discharge state or an over-charge state; determining a target motor from the plurality of motors according to the abnormal state and the working state, wherein when the abnormal state is an over-discharge state, the target motor is a motor in the plurality of motors whose working state is a driving state, and when the abnormal state is an over-charge state, the target motor is a motor in the plurality of motors whose working state is a recovery state; The absolute value of the output torque of at least one of the target motors is reduced to remove the power battery from the abnormal state.

2. The vehicle control method according to claim 1, characterized in that: The reducing the absolute value of the output torque of at least one of the target motors comprises: obtaining high-voltage terminal power of the plurality of motors and a remaining battery power of the power battery, wherein when the power battery is in a discharging state, the remaining battery power is the remaining available driving power, and when the power battery is in a charging state, the remaining battery power is the remaining available recovery power; The absolute value of the output torque of at least one of the target motors is reduced according to the high-voltage end power of the plurality of motors and the remaining power of the battery.

3. The vehicle control method according to claim 2, characterized in that: The reducing the absolute value of the output torque of at least one of the target motors according to the high-voltage end power of the plurality of motors and the remaining power of the battery comprises: Determine the difference between the remaining power of the battery and the total power to obtain a target excess power, wherein the total power is the sum of the high-voltage end powers of the multiple motors; Sorting each motor in the target motor according to motor efficiency to obtain a first sorting result, wherein when the power battery is in a discharging state, the motor efficiency order is a sorting from small to large motor discharge efficiency, and when the power battery is in a charging state, the motor efficiency order is a sorting from large to small motor feedback efficiency; According to the target excess power and the first sorting result, the absolute value of the output torque of at least one of the target motors is reduced.

4. The vehicle control method according to claim 3, characterized in that: Reducing the absolute value of the output torque of at least one of the target motors according to the target excess power and the first sorting result includes: The first motor in the first sorting result is used as the motor to be adjusted; Comparing the target power value with the absolute value of the high-voltage end power of the motor to be adjusted, the target power value being the absolute value of the target excess power; If the target power value is less than or equal to the absolute value of the high-voltage end power of the motor to be adjusted, determining the corrected output power of the motor to be adjusted according to the target power value, and reducing the absolute value of the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted; If the target power value is greater than the absolute value of the high-voltage end power of the motor to be adjusted, the high-voltage end power of the motor to be adjusted is used as the corrected output power of the motor to be adjusted, the absolute value of the output torque of the motor to be adjusted is reduced based on the corrected output power of the motor to be adjusted, and the motor to be adjusted is deleted from the first sorting result to obtain a second sorting result; Then, the difference between the target power value and the absolute value of the high-voltage end power of the motor to be adjusted is used as the target power value, and the second sorting result is used as the first sorting result, and the step of using the first motor in the first sorting result as the motor to be adjusted is executed until the target power value is less than or equal to the absolute value of the high-voltage end power of a motor in the first sorting result.

5. The vehicle control method according to claim 4, characterized in that: The step of reducing the absolute value of the output torque of the motor to be adjusted based on the corrected output power of the motor to be adjusted comprises: Obtaining a corrected output torque corresponding to the corrected output power of the motor to be adjusted; Subtracting the absolute value of the requested torque of the motor to be adjusted from the absolute value of the corrected output torque to obtain a target torque; The motor to be adjusted is controlled to output the target torque.

6. The vehicle control method according to claim 4, characterized in that: When the power battery is in an abnormal state, the vehicle control method further includes: timing the time during which the power battery is in an abnormal state to obtain a timing duration; After the absolute values ​​of the output torques of all the target motors are reduced, the vehicle control method further includes: If the timing duration is greater than or equal to the second duration and less than the first duration, increasing the absolute value of the target excess power; The target excess power after the absolute value is increased is used as the target excess power, and the step of using the first motor in the first sorting result as the motor to be adjusted is performed.

7. The vehicle control method according to claim 6, characterized in that: Increasing the absolute value of the target excess power includes: determining a first preset power corresponding to the battery driving power of the power battery and the vehicle speed as the reserve power, or determining a second preset power corresponding to the battery recovery power of the power battery and the vehicle speed as the reserve power; The absolute value of the reserve power is added to the absolute value of the target excess power to obtain the target excess power with an increased absolute value.

8. A vehicle control device, characterized in that: The vehicle includes a power battery and a plurality of motors, wherein the working states of the motors include a driving state and a recovery state. When the working state of the motors is the driving state, the power battery supplies power to the motors, and when the working state of the motors is the recovery state, the motors charge the power battery. The vehicle control device comprises: a state acquisition module, configured to acquire the operating states of the plurality of motors when the power battery is in an abnormal state, wherein the abnormal state is an over-discharge state or an over-charge state; a motor selection module, configured to determine a target motor from the plurality of motors based on the abnormal state and the working state, wherein when the abnormal state is an over-discharge state, the target motor is a motor whose working state is a driving state among the plurality of motors; and when the abnormal state is an over-charge state, the target motor is a motor whose working state is a recovery state among the plurality of motors; The torque adjustment module is configured to reduce an absolute value of an output torque of at least one of the target motors so as to allow the power battery to escape from the abnormal state.

9. A vehicle, characterized in that: The vehicle comprises: a memory for storing executable program code; A processor is used to call and run the executable program code from the memory, so that the vehicle executes the vehicle control method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed, the vehicle control method according to any one of claims 1 to 7 is implemented.

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