A method of vehicle control and a vehicle

Abstract

The application provides a vehicle control method and vehicle, the method is applied to the field of vehicle, the method comprises the following steps: in the process of vehicle driving, if it is detected that the high-voltage battery is abnormal, the vehicle is controlled to enter the limp mode; in the limp mode, if it is detected that the abnormality of the high-voltage battery is eliminated, the motor is controlled to stop generating electricity; after the motor stops generating electricity, if it is detected that the motor side voltage drops to less than or equal to the preset voltage, the pre-charging relay of the high-voltage battery is controlled to be closed; the preset voltage is lower than the minimum working voltage of the high-voltage battery; after the pre-charging relay is closed, if it is detected that the absolute value of the voltage difference between the motor side voltage and the high-voltage battery side voltage is less than the preset voltage difference value, the main relay is controlled to be closed, and the pre-charging relay is controlled to be disconnected, so that the vehicle is switched from the limp mode to the normal mode. The method can safely and conveniently enable the high-voltage battery to switch to the normal mode after the abnormality of the high-voltage battery is eliminated in the limp mode.

Description

Technical Field

[0001] The present application relates to the field of vehicles, and more particularly, to a vehicle control method and a vehicle in the field of vehicles. Background Art

[0002] When a high-voltage battery failure occurs in a hybrid vehicle, the vehicle enters limp-home mode to maintain basic driving functionality. In limp-home mode, the high-voltage battery no longer outputs high-voltage power, and the vehicle relies on the engine or other backup power source to continue driving. However, if the high-voltage battery failure resolves itself during subsequent driving, the high-voltage battery is typically not directly activated. Instead, the driver is required to stop and restart the vehicle to reactivate the high-voltage battery, adding to the burden and inconvenience of driving. Therefore, how to safely and conveniently activate the high-voltage battery in limp-home mode to transition to normal operation has become a pressing technical challenge. Summary of the Invention

[0003] The present application provides a vehicle control method and a vehicle, which can safely and conveniently enable the high-voltage battery to switch to the normal mode after the abnormality of the high-voltage battery is eliminated in the limp mode.

[0004] In a first aspect, a method for controlling a vehicle is provided, the method comprising: during vehicle driving, if an abnormality is detected in a high-voltage battery, controlling the vehicle to enter a limp home mode; wherein, in the limp home mode, the main relay of the high-voltage battery is disconnected, the engine drives the vehicle to travel and the engine drives the motor to rotate and generate electricity; in the limp home mode, if it is detected that the abnormality of the high-voltage battery is eliminated, controlling the motor to stop generating electricity; after the motor stops generating electricity, if it is detected that the motor side voltage drops to less than or equal to a preset voltage, controlling the pre-charge relay of the high-voltage battery to close; wherein, the preset voltage is lower than the minimum operating voltage of the high-voltage battery; after the pre-charge relay is closed, if it is detected that the absolute value of the voltage difference between the motor side voltage and the high-voltage battery side voltage is less than a preset voltage difference, controlling the main relay to close, and controlling the pre-charge relay to disconnect, so that the vehicle switches from the limp home mode to the normal mode.

[0005] The above technical solution, in the process of vehicle driving, if the high-voltage battery is detected to be abnormal, the vehicle is controlled to enter the limp mode, so that the vehicle can continue to drive safely when the high-voltage battery fails, and the vehicle is prevented from losing power completely due to power supply interruption. The engine drives the motor to rotate and generate electricity, thereby ensuring the continuous operation of the basic functions of the vehicle. In the limp mode, if it is detected that the abnormality of the high-voltage battery is eliminated, it means that the conditions for re-enabling the high-voltage battery exist, and at this time, the motor is controlled to stop generating electricity to provide a preparation condition for switching to the normal mode. After the motor stops generating electricity, the motor-side voltage begins to drop. During the process of the motor-side voltage dropping, if it is detected that the motor-side voltage drops to less than or equal to a preset voltage, the pre-charge relay is controlled to be closed. After the pre-charge relay is closed, the motor-side voltage is further pulled up. With the increase of the motor-side voltage, if it is detected that the absolute value of the voltage difference between the motor-side voltage and the high-voltage battery-side voltage is less than a preset voltage difference value, at this time, the main relay is controlled to be closed to avoid the problem of main relay ablation that may occur when the main relay is directly closed due to the too large voltage difference. Moreover, since the preset voltage is lower than the minimum working voltage of the high-voltage battery, after the pre-charge relay is closed, the motor-side voltage can start to rise from below the minimum working voltage of the high-voltage battery, thereby ensuring that, during the process of the motor-side voltage rising, there is a process in which the motor-side voltage approaches the high-voltage battery-side voltage, and further ensuring that the absolute value of the voltage difference between the motor-side voltage and the high-voltage battery-side voltage can be detected to be less than the preset voltage difference value, thereby providing a safe condition for closing the main relay. At the same time, during the entire process, the driver does not need to stop the vehicle, unnecessary parking and restarting operations are reduced, and the driving convenience and comfort are improved.

[0006] In combination with the first aspect, in some possible implementation manners, before the abnormality of the high-voltage battery is eliminated, the method further includes: controlling the high-voltage-to-low-voltage device of the vehicle to enter a voltage reduction state; and in the voltage reduction state, controlling the high-voltage-to-low-voltage device to perform voltage reduction processing on the power generation voltage of the motor to supply power to the low-voltage system of the vehicle.

[0007] The above technical solution, before the abnormality of the high-voltage battery is eliminated, the high-voltage battery cannot output high voltage, and the high-voltage-to-low-voltage device is controlled to enter a voltage reduction state to meet the power supply demand of the low-voltage system of the vehicle. Moreover, the high-voltage-to-low-voltage device in the voltage reduction state can serve as a load of the motor to restrict the rapid rise of the power generation voltage of the motor, so as to ensure that the power generation voltage of the motor is maintained within a safe and controllable range, thereby avoiding that the power generation voltage of the motor is too high.

[0008] In some possible implementation manners, in the limp-home mode, a maximum generation voltage of the motor is a first target voltage, and the first target voltage is greater than or equal to a rated voltage of the high-voltage battery; and the control of the high-to-low voltage device of the vehicle into the step-down state includes: detecting a generation voltage of the motor in the generation process; and if the generation voltage is greater than a preset voltage threshold and less than a second target voltage, controlling the high-to-low voltage device to start entering the step-down state; and the second target voltage is less than or equal to the first target voltage.

[0009] The above technical solution provides a longer voltage interval for the high-to-low voltage device to restrict the rapid rise of the generation voltage of the motor in the limp-home mode by setting a higher first target voltage. The high-to-low voltage device is controlled to enter the step-down state when the generation voltage is greater than the preset voltage threshold and less than the second target voltage, which is equivalent to avoiding the stage in which the generation voltage of the motor changes rapidly (the stage in which the motor starts to generate electricity and the stage in which the generation voltage of the motor rapidly reaches the maximum generation voltage). If the generation voltage changes too rapidly, the high-to-low voltage device may be difficult to restrict the rapidly rising generation voltage of the motor even if the high-to-low voltage device enters the step-down state. When the generation voltage is between the preset voltage threshold and the second target voltage, the generation voltage changes relatively slowly, and therefore, the high-to-low voltage device is more likely to restrict the generation voltage during this period. In combination with the dynamic monitoring of the generation voltage and the timely control of the high-to-low voltage device to enter the step-down state to supply power to the low-voltage system, the risk that may be caused by the excessively high generation voltage of the motor is avoided, the stable power supply of the low-voltage system is ensured, the safe management of the generation voltage of the motor is effectively achieved, and the safety and reliability of the vehicle are improved.

[0010] In combination with the first aspect and the above implementation manners, after the motor stops generating electricity, the method further includes: timing from a time at which the motor stops generating electricity to obtain a timing duration; and after the timing duration reaches a first preset duration, controlling the high-to-low voltage device to exit the step-down state.

[0011] The above technical solution controls the high-to-low voltage device to exit the step-down state after the motor stops generating electricity. After the motor stops generating electricity, the voltage on the motor side starts to decrease. By controlling the high-to-low voltage device to exit the step-down state after the first preset duration, the high-to-low voltage device can continue to serve as a load of the motor to continue to consume residual electricity remaining after the motor stops generating electricity, which is beneficial to accelerating the decrease rate of the voltage on the motor side, so that the voltage on the motor side rapidly decreases to be less than or equal to the preset voltage, to meet the condition of closing the pre-charging relay as soon as possible. This is beneficial to shortening the duration required for closing the pre-charging relay and accelerating the speed of switching the vehicle from the limp-home mode to the normal mode after the motor stops generating electricity.

[0012] In some possible implementation manners, after the motor stops generating electricity, the method further includes: controlling the high-to-low voltage device to exit the voltage reduction state without delay, and delaying sending of the closing instruction of the pre-charging relay for a second preset time length; and if it is detected that the motor-side voltage drops to be less than or equal to the preset voltage, controlling the pre-charging relay of the high-voltage battery to be closed, including: if it is detected that the motor-side voltage drops to be less than or equal to the preset voltage, controlling the pre-charging relay of the high-voltage battery to be closed based on the closing instruction.

[0013] The above technical solution can ensure that the motor-side voltage stably drops to be lower than the preset voltage after the motor stops generating electricity, the high-to-low voltage device is controlled to exit the voltage reduction state without delay, and the closing instruction of the pre-charging relay is sent after a second preset time length, which not only avoids false reporting of a fault by the control system, but also improves the reliability and stability of the system. It can be understood that after the high-to-low voltage device exits the voltage reduction state, the motor is equivalent to losing the high-to-low voltage device as a load, and then the dropping speed of the motor-side voltage becomes slow. It takes a certain time length to wait for the motor-side voltage to drop to be less than or equal to the preset voltage, and the closing instruction of the pre-charging relay is sent after a second preset time length, which is beneficial to making the control system know that the waiting time length is actually waiting for the closing instruction of the pre-charging relay, rather than an operation delay caused by other unknown reasons, which helps to avoid false reporting of a fault by the control system due to unknown waiting, and improves the reliability and stability of the system.

[0014] In some possible implementation manners, after the vehicle enters the limp-home mode, the method further includes: setting a state of a compressor of an air conditioning system of the vehicle to a power-adjustable state, and controlling a power demand of the compressor to be 0; or setting the state of the compressor to a prohibited state; and in the prohibited state, the compressor is prohibited from working.

[0015] The above technical solution can save the electric energy generated by the motor for more critical driving functions, and avoid the compressor as a load of the motor, which affects the stable output of the motor-generated voltage. Setting the compressor to the power-adjustable state and ensuring that the power demand of the compressor is 0 is actually an energy-saving measure achieved by flexible control logic. Even in the case of limited power, the compressor still retains the ability to be started at any time to cope with sudden temperature control requirements.

[0016] With reference to the first aspect and the above implementation manners, in some possible implementation manners, after the vehicle is switched from the limp-home mode to the normal mode, the method further includes: setting a state of the compressor to a power-adjustable state, and allowing a power demand of the compressor to be greater than 0; or setting the state of the compressor to a normal state; wherein in the normal state, the compressor is allowed to work normally.

[0017] The above technical solution, after the vehicle is restored to the normal mode, the high-voltage battery can work normally, and therefore the state of the compressor is set to the power-adjustable state, and the power demand of the compressor is allowed to be greater than 0, or the state of the compressor is set to the normal state, which is beneficial to timely restore the work of the compressor to realize the functions related to the compressor such as starting the air conditioner and starting the heater.

[0018] With reference to the first aspect and the above implementation manners, in some possible implementation manners, after the control of the main relay being closed and the control of the pre-charging relay being disconnected to switch the vehicle from the limp-home mode to the normal mode, the method further includes: if the current gear of the vehicle is a driving gear and the remaining power of the high-voltage battery is greater than a preset power threshold, activating a target flag; wherein the target flag indicates that the vehicle has been switched to the normal mode; and in a case where the target flag is activated, allowing the high-voltage battery to supply power to high-voltage electrical equipment and allowing the motor to participate in driving of the vehicle.

[0019] The above technical solution, by activating the target flag, the control system can explicitly inform each subsystem / controller that the high-voltage battery has restored normal power supply capability and the motor also has normal driving function. This not only avoids misjudgment or delayed reaction caused by information asynchronization, but also improves the overall efficiency and safety of the system, and ensures the consistency and reliability of the driving experience.

[0020] With reference to the first aspect and the above implementation manners, in some possible implementation manners, in a case where the abnormality of the high-voltage battery is eliminated, the method further includes: if the vehicle is not detected to be switched from the limp-home mode to the normal mode within a third preset time length, switching the vehicle back to the limp-home mode.

[0021] The above technical solution ensures that even if the high-voltage battery is restored to normal, but due to other reasons, the vehicle is still in a relatively safe state when it cannot be successfully switched to the normal mode, avoiding potential risks.

[0022] In a second aspect, a device for vehicle control is provided, comprising: a limp-home control module configured to control the vehicle to enter a limp-home mode if an abnormality of a high-voltage battery is detected during driving of the vehicle; wherein in the limp-home mode, a main relay of the high-voltage battery is opened, the vehicle is driven by an engine, and the engine drives a motor to generate electricity; a motor control module configured to control the motor to stop generating electricity if the abnormality of the high-voltage battery is eliminated in the limp-home mode; a pre-charge relay control module configured to control a pre-charge relay of the high-voltage battery to be closed if a motor-side voltage drops to be less than or equal to a preset voltage after the motor stops generating electricity; wherein the preset voltage is lower than a minimum working voltage of the high-voltage battery; and a mode switching control module configured to control the main relay to be closed and the pre-charge relay to be opened to switch the vehicle from the limp-home mode to a normal mode if an absolute value of a voltage difference between the motor-side voltage and a high-voltage battery-side voltage is less than a preset voltage difference after the pre-charge relay is closed.

[0023] In a third aspect, a vehicle is provided, comprising: a memory configured to store executable program code; and a processor configured to invoke and run the executable program code from the memory, so that the vehicle performs the method in the first aspect or any possible implementation manner of the first aspect.

[0024] In a fourth aspect, a computer program product is provided, comprising: computer program code configured to cause a computer to perform the method in the first aspect or any possible implementation manner of the first aspect when the computer program code is run on the computer.

[0025] In a fifth aspect, a computer-readable storage medium is provided, which stores computer program code configured to cause a computer to perform the method in the first aspect or any possible implementation manner of the first aspect when the computer program code is run on the computer. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a schematic flowchart of a method for vehicle control provided by an embodiment of the present application;

[0027] Figure 2 is an architecture schematic diagram of a high-voltage system of a vehicle provided by an embodiment of the present application;

[0028] Figure 3 is another architecture schematic diagram of a high-voltage system of a vehicle provided by an embodiment of the present application;

[0029] Figure 4is a schematic diagram of a relationship between a generated voltage and time after a motor starts generating electricity, provided by an embodiment of the present application.

[0030] Figure 5 is a schematic diagram of a principle of activating a target flag bit, provided by an embodiment of the present application.

[0031] Figure 6 is a schematic diagram of a structure of a vehicle control device, provided by an embodiment of the present application.

[0032] Figure 7 is a schematic diagram of a structure of a vehicle, provided by an embodiment of the present application. DETAILED DESCRIPTION

[0033] The technical solutions in the present application will be described clearly and exhaustively below with reference to the drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " represents the meaning of or, for example, A / B can represent A or B: "and / or" in the text only describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases of A alone, A and B together, and B alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0034] Hereinafter, the terms "first" and "second" are only used for description purposes, and cannot be understood as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first" and "second" can explicitly or implicitly include one or more features.

[0035] During driving, when the high-voltage battery fails, the hybrid vehicle enters a limp-home mode to maintain basic driving functions. In the limp-home mode, the high-voltage battery no longer outputs high-voltage electricity, and the vehicle relies on the engine or other backup power sources to continue driving. However, if the high-voltage battery failure is self-corrected during subsequent driving, the vehicle cannot be switched to high-voltage battery driving at this time, that is, the vehicle cannot be electrically driven. That is, during driving in the limp-home mode, if the high-voltage battery failure is recovered, the vehicle cannot start driving the motor with high-voltage battery electricity, turn on the air conditioner, turn on the heater, etc.

[0036] The present inventors have found through research that during driving, if the high-voltage battery recovers from a failure state to a normal state, directly starting to use the high-voltage battery can cause the following problems:

[0037] High-voltage attack problem: In a fault state, the high-voltage battery, the engine drives the motor to generate high-voltage electricity. If the high-voltage battery returns to normal, the high-voltage battery is directly enabled to generate high-voltage electricity. The high-voltage electricity generated by the motor and the high-voltage electricity generated by the high-voltage battery meet together, which may cause a high-voltage side to attack a low-voltage side problem, affecting the safety of the vehicle.

[0038] Main relay safety risk: After the high-voltage battery returns to normal, the main relay needs to be closed to enable the high-voltage battery. When the high-voltage battery returns to normal, there is a certain gap between the voltage on the high-voltage battery side and the voltage on the motor side, resulting in a large voltage difference between the two sides of the main relay. At this time, directly closing the main relay may cause the main relay to be ablated, further affecting the safety and reliability of the vehicle.

[0039] Based on the above problems, in the existing technology, if the high-voltage battery returns to normal from a fault state in the limp mode, the high-voltage battery is usually not directly enabled. Instead, the driver is required to stop the vehicle and restart the vehicle to re-enable the high-voltage battery. Although this approach ensures safety, it also brings the following inconveniences:

[0040] Complex operation: The driver needs to stop the vehicle and restart it, increasing the driving burden and inconvenience.

[0041] Poor driving experience: Frequent stop and restart operations reduce the driving experience, especially in emergency situations or busy traffic sections, which may affect driving efficiency and safety.

[0042] Therefore, how to safely and conveniently enable the high-voltage battery in the limp mode has become a technical problem to be solved. Based on this, the embodiments of the present application provide a vehicle control method, which is applied to a hybrid vehicle and can be applied to a controller or control system of the vehicle. The method aims to safely and conveniently enable the high-voltage battery after it returns to normal from an abnormal state, so as to restore the vehicle from the limp mode to the normal mode.

[0043] Figure 1 is a schematic flowchart of a vehicle control method provided by the embodiments of the present application.

[0044] As shown in the example of Figure 1 , the method comprises:

[0045] Step 101: If an abnormality of the high-voltage battery is detected during vehicle driving, the vehicle is controlled to enter a limp mode; wherein in the limp mode, the main relay of the high-voltage battery is disconnected, the engine drives the vehicle to drive and the engine drives the motor to rotate and generate electricity;

[0046] Step 102: In the limp mode, if the abnormality of the high-voltage battery is eliminated, the motor is controlled to stop generating electricity;

[0047] Step 103: After the motor stops generating electricity, if it is detected that the motor side voltage drops to less than or equal to a preset voltage, controlling the pre-charge relay of the high-voltage battery to close; wherein the preset voltage is lower than the minimum operating voltage of the high-voltage battery;

[0048] Step 104: After the pre-charge relay is closed, if it is detected that the absolute value of the voltage difference between the motor side voltage and the high-voltage battery side voltage is less than the preset voltage difference, the main relay is controlled to close and the pre-charge relay is controlled to open, so that the vehicle switches from limp home mode to normal mode.

[0049] exist Figure 1 In the illustrated embodiment, if an abnormality is detected in the high-voltage battery during vehicle operation, the vehicle enters limp-home mode. This ensures safe driving even in the event of a high-voltage battery failure, preventing a complete loss of power due to a power outage. The engine drives the motor to generate electricity, ensuring continued operation of the vehicle's basic functions. While in limp-home mode, if the abnormality is resolved, indicating the conditions are present for reactivating the battery, the motor is controlled to stop generating electricity, preparing for a transition to normal mode. After the motor stops generating electricity, the motor voltage begins to decrease. During this decrease, if the motor voltage drops below or equal to a preset voltage, the pre-charge relay is controlled to close. After the pre-charge relay closes, the motor voltage is further increased. As the motor voltage increases, if the absolute value of the voltage difference between the motor voltage and the high-voltage battery voltage is detected to be less than a preset voltage difference, the main relay is controlled to close to prevent main relay burnout, which could occur if the voltage difference is too large. Furthermore, because the preset voltage is lower than the high-voltage battery's minimum operating voltage, the motor-side voltage can begin to rise from below the high-voltage battery's minimum operating voltage after the pre-charge relay is closed. This ensures that as the motor-side voltage rises, it approaches the high-voltage battery voltage. This ensures that the absolute value of the voltage difference between the motor-side voltage and the high-voltage battery voltage is detected to be less than the preset voltage difference, providing a safe condition for closing the main relay. Furthermore, the driver does not need to stop the vehicle during this entire process, reducing unnecessary stops and restarts and improving driving convenience and comfort.

[0050] Moreover, after the high-voltage battery returns to normal, it will not be directly enabled to generate high-voltage electricity. Instead, the main relay will be closed to enable the high-voltage battery to generate high-voltage electricity only when the difference between the voltage on the battery side and the voltage on the motor side is small, ensuring that the high-voltage side will not attack the low-voltage side during the entire process, thereby ensuring the safety and stability of the vehicle.

[0051] Below Figure 1The specific implementation of each step in the illustrated embodiment is described:

[0052] In step 101, the parameters of the high-voltage battery (such as voltage, current, temperature, etc.) are monitored in real time by the battery management system (BMS) inside the vehicle. Once an abnormality is detected (for example, the voltage is too low, the internal resistance is too large, the temperature is abnormally high, etc.), the vehicle is controlled to enter limp-home mode. The way to control the vehicle to enter limp-home mode can include: controlling the main relay to be disconnected to cut off the connection between the high-voltage battery and the vehicle electrical system to ensure safety, controlling the engine to drive the vehicle to travel to maintain the basic driving ability of the vehicle, and controlling the engine to drive the motor to rotate to generate electricity to maintain the basic power demand of the vehicle (such as lighting, instrument panel, etc.).

[0053] For example, the state of the motor includes: a generating state, a torque control state, a speed control state, a standby state (STANDBY), an initialization state, and a shutdown state. The generating state refers to the operation of the motor as a generator, which is driven by the engine to rotate and convert mechanical energy into electrical energy. The torque control state refers to the control of the motor according to the set torque value, which is used to accurately adjust the output torque of the motor. The speed control state refers to the control of the motor according to the set speed value, which is used to accurately adjust the speed of the motor. The standby state refers to the zero-power waiting state of the motor, in which the motor rotates but does not generate electricity and does not output torque. The initialization state refers to the self-checking and initialization process before the motor starts, which ensures that all parameter settings are correct and ready for normal work. The shutdown state refers to the complete stop of the motor, which cuts off all power supply. When the vehicle enters the limp-home mode, the control system controls the motor to jump to the generating state.

[0054] Figure 2 is a schematic diagram of a high-voltage system of a vehicle provided by an embodiment of the present application.

[0055] For example, as Figure 2 shown, the high-voltage system of the vehicle includes: a high-voltage battery 201, a main relay, a pre-charging relay 204, a pre-charging resistor 205, and a motor 206, the main relay includes a main positive relay 202, a main negative relay 203, a pre-charging relay 204, a pre-charging resistor 205, and a motor 206.

[0056] During vehicle travel, if an abnormality of the high-voltage battery 201 is detected, the main positive relay 202 and the main negative relay 203 are controlled to be disconnected, the engine is controlled to drive the vehicle to travel, and the engine is controlled to drive the motor 206 to rotate to generate electricity, so that the vehicle enters the limp-home mode. That is, the control of the relay to be disconnected in the above step 101 includes: controlling the main positive relay 202 and the main negative relay 203 to be disconnected.

[0057] In a possible implementation, after the vehicle enters the limp-home mode, the method further includes: setting a state of a compressor of an air conditioning system of the vehicle to a power adjustable state, and controlling a power requirement of the compressor to be 0; or setting the state of the compressor of the air conditioning system of the vehicle to a prohibited state; wherein in the prohibited state, the compressor is prohibited from working.

[0058] The compressor of the air conditioning system is a key component, and its working state directly affects the comfort of the vehicle interior and the energy utilization efficiency. According to different operating conditions and requirements, the state of the compressor includes a prohibited state, a power adjustable state, and a normal state. In the prohibited state, the compressor is prohibited from working in any form. The power adjustable state is a state that allows the compressor to work but limits its output power. In the normal state, the compressor normally works according to the requested power level to provide the required refrigeration or heating capacity.

[0059] After the vehicle enters the limp-home mode, the high-voltage battery cannot output high-voltage electricity, although the motor can generate electricity, but the power resources of the vehicle become limited, and the power supply of key systems (such as steering, braking, etc.) must be prioritized. The compressor of the air conditioning system consumes a large amount of electricity, especially in high-temperature or low-temperature environments, so setting the state of the compressor to the power adjustable state or the prohibited state can save valuable electrical energy for more critical driving functions.

[0060] During the high-voltage battery failure, the voltage and current generated by the motor may be unstable. The compressor is a high-power device and is sensitive to voltage fluctuations. In order to avoid damage to the compressor or other devices due to unstable voltage, limiting its power or prohibiting its work is an effective protection measure. Moreover, if the compressor is allowed to work, the compressor may become an interfering load for the motor in the power generation state, affecting the stable output of the motor generation voltage. Therefore, in the present embodiment, during the high-voltage battery failure, the vehicle is in the limp-home mode, and the compressor is controlled to be in the prohibited state, or even if the compressor is controlled to be in the power adjustable state, the power requirement of the compressor is also controlled to be 0, that is, the compressor has no power requirement. Controlling the power requirement of the compressor to be 0 can be understood as controlling the power request value of the compressor to be 0, that is, limiting the power request value of the compressor to 0.

[0061] In the above implementation, after the vehicle enters limp home mode, the compressor is set to a power-adjustable state and its power demand is controlled to zero. Alternatively, the compressor is disabled. This conserves motor-generated energy for more critical driving functions and prevents the compressor from acting as a load on the motor, impacting the stable output of the motor's generated voltage. Setting the compressor to a power-adjustable state and ensuring no power demand is an energy-saving measure achieved through flexible control logic. Even under power constraints, the compressor remains ready to start at any time to meet unexpected temperature control needs.

[0062] In one possible implementation, in limp home mode, before the abnormality of the high-voltage battery is eliminated, it also includes: controlling the vehicle's high-voltage to low-voltage device to enter a step-down state; in the step-down state, controlling the high-voltage to low-voltage device to step down the generated voltage of the motor to power the vehicle's low-voltage system.

[0063] Figure 3 This is a schematic diagram of the architecture of another high-voltage system for a vehicle provided in an embodiment of the present application.

[0064] For example, Figure 3 As shown, the high-voltage system includes: a high-voltage battery 201, a main positive relay 202, a main negative relay 203, a pre-charge relay 204, a pre-charge resistor 205, a motor 206, a high-voltage to low-voltage device 207, and a low-voltage system 208. The high-voltage to low-voltage device 207 can be a DC-DC converter (DC-DC), and the low-voltage system 208 can be a 12V system.

[0065] When high-voltage converter 207 is in the reduced voltage state, the control system instructs high-voltage converter 207 to "propose a demand" at a constant value of the "minimum 12V power required for the entire vehicle," or the control system instructs motor 206 to provide a constant power supply to high-voltage converter 207, so that high-voltage converter 207 can power low-voltage system 208. This constant power supply mechanism enables high-voltage converter 207 to continuously provide stable low-voltage power while preventing the generated voltage of motor 206 from rising too quickly.

[0066] The states of the high-to-low voltage device include a step-down state, a standby state, an initialization state, and a shutdown state. The step-down state refers to the high-to-low voltage device performing step-down processing on the power generation voltage of the motor to meet the power supply requirements of the low-voltage system (such as a 12V battery and various low-voltage electrical appliances) of the vehicle. The standby state refers to the high-to-low voltage device being in a zero-power standby state, ready to accept a start command at any time, and maintaining communication connection with the control system. The initialization state refers to the self-checking and initialization process before the high-to-low voltage device starts, to ensure that all parameters are correctly set and ready for normal operation. The shutdown state refers to the high-to-low voltage device completely stopping working, cutting off all power supply, and not performing any operation. In the limp-home mode, before the abnormality of the high-voltage battery is eliminated, the control system controls the high-to-low voltage device of the vehicle to enter the step-down state from the standby state.

[0067] In addition, the inventors of the present application have found through research that, in order to make the high-to-low voltage device enter the step-down state and more easily suppress the rise of the power generation voltage of the motor, the motor is first allowed to generate electricity for a while, and then the high-to-low voltage device is controlled to enter the step-down state.

[0068] In one possible implementation, in the limp-home mode, the maximum power generation voltage of the motor is a first target voltage, and the first target voltage is greater than or equal to the rated voltage of the high-voltage battery; and the control of the high-to-low voltage device of the vehicle to enter the step-down state includes: detecting the power generation voltage of the motor during power generation; and if the power generation voltage is greater than a preset voltage threshold and less than a second target voltage, controlling the high-to-low voltage device to start entering the step-down state; wherein the second target voltage is less than or equal to the first target voltage.

[0069] In this implementation, in the limp-home mode, when the engine drives the motor 206 to rotate to generate electricity, the maximum power generation voltage of the motor 206 is set as the first target voltage. Assuming that the rated voltage of the high-voltage battery 201 is 400V, the first target voltage can be greater than or equal to 400V.

[0070] It can be understood that after the motor 206 starts to generate electricity, it takes a period of time for the actual power generation voltage to rise to the first target voltage. During this period, the power generation voltage of the motor 206 during power generation is detected, and if the power generation voltage is greater than a preset voltage threshold and less than a second target voltage, the high-to-low voltage device 207 is controlled to start entering the step-down state, to perform step-down processing on the power generation voltage of the motor 206, to achieve power supply to the low-voltage system 208 of the vehicle, and at the same time, the high-to-low voltage device 207 entering the step-down state can serve as a load of the motor 206, to restrict the rapid rise of the power generation voltage of the motor 206.

[0071] Considering that the maximum generation voltage of the motor is designed based on the rated voltage of the high-voltage battery, if the generation voltage of the motor is too high, the electrical equipment may be damaged; and if the generation voltage is too low, the state of the motor at the initial stage of power generation is difficult to control. Therefore, the vehicle control system requires the high-to-low voltage device to enter the voltage reduction state at an appropriate time, so as to restrain the rapid rise of the generation voltage by taking the motor as a load before the motor generates voltage and the second target voltage is reached, ensure that the generation voltage of the motor is maintained within a safe and controllable range, and avoid the generation voltage of the motor being too high. Moreover, the high-to-low voltage device will not enter the voltage reduction state at the initial stage of power generation of the motor, so as to avoid the state of the motor at the initial stage of power generation being uncontrollable. At the same time, the maximum generation voltage of the motor is set to be greater than or equal to the rated voltage of the high-voltage battery, which provides a longer voltage interval for the high-to-low voltage device to restrain the rapid rise of the motor voltage, so as to facilitate the high-to-low voltage device to enter the voltage reduction state at an appropriate time and realize the restraint of the generation voltage of the motor.

[0072] For example, refer to Figure 4 , Figure 4 is a schematic diagram of the relationship between the generation voltage and the time after the motor starts to generate power. Figure 4 For example, when the maximum generation voltage of the motor is 400V, U1 is the preset voltage threshold, and U2 is the second target voltage, U1 is greater than 0, and U2 is less than 400V. For example, U1 = 130V and U2 = 360V. In the case that the generation voltage is between U1 and U2, the high-to-low voltage device is controlled to enter the voltage reduction state, and the restraint effect on the generation voltage of the motor is good. Figure 4 It can be seen that the high-to-low voltage device is selected to intervene and enter the voltage reduction state when the generation voltage is between U1 and U2, which is equivalent to avoiding the stage in which the generation voltage of the motor changes rapidly (the initial stage of power generation and the stage of rapidly reaching the maximum generation voltage). If the generation voltage changes too fast, it may be difficult for the high-to-low voltage device to restrain the rapidly rising generation voltage of the motor even if it enters the voltage reduction state. When the generation voltage is between U1 and U2, the generation voltage changes relatively slowly, so it is easier to realize the restraint of the generation voltage by controlling the high-to-low voltage device to enter the voltage reduction state when the generation voltage is between U1 and U2.

[0073] In the above technical solution, in the limping mode, a higher first target voltage is set, which provides a longer voltage interval for the high-to-low voltage device to restrict the rapid rise of the motor generated voltage, so as to facilitate the high-to-low voltage device to enter the voltage reduction state at the appropriate time, thereby realizing effective control of the motor generated voltage. In combination with dynamic monitoring of the generated voltage, timely control of the high-to-low voltage device to enter the voltage reduction state to supply power to the low-voltage system, not only the risk caused by the high motor generated voltage is avoided, but also the stable power supply of the low-voltage system is ensured, the safety management of the motor generated voltage is effectively realized, and the safety and reliability of the vehicle are improved.

[0074] In step 102, considering that the abnormality of the high-voltage battery may also be self-eliminated during the driving of the vehicle. For example, after the high-voltage battery overheats and reports an abnormality at noon in a hot summer, the main relay is disconnected and the high-voltage battery stops working. At this time, the engine is controlled to drive the vehicle to continue driving, and after half an hour, the high-voltage battery cools down and the abnormality of the high-voltage battery overheating is eliminated. Based on this, in the limping mode, the BMS can continue to monitor the high-voltage battery in real time and check whether the parameters of the high-voltage battery return to normal. For example, a series of diagnostic criteria (such as the voltage returning to the normal range, the temperature stabilizing, etc.) are set, and when the parameters return to normal, it is determined that the abnormality of the high-voltage battery has been eliminated. If it is detected that the abnormality of the high-voltage battery is eliminated, the motor is controlled to stop generating electricity, for example, the motor is controlled to jump from the generating state to the standby state, so that the motor rotates but does not generate electricity.

[0075] In step 103, after the motor stops generating electricity, the motor-side voltage is the residual electricity left after the motor stops generating electricity. Since the high-voltage battery does not output high voltage at this time, the motor-side voltage will gradually decrease. Referring to Figure 2 , the motor-side voltage is the voltage between one side of the motor 206 and the second end of the main positive relay 202 in Figure 2 , such as the voltage between points c and d in the figure. During the decrease of the motor-side voltage, the motor-side voltage can be continuously detected, and if it is detected that the motor-side voltage decreases to less than or equal to a preset voltage, the pre-charge relay is controlled to be closed.

[0076] The preset voltage is lower than the minimum working voltage of the high-voltage battery. It can be understood that the high-voltage battery has a corresponding normal working voltage range. For example, the normal working voltage range of the high-voltage battery is 270V to 390V, the minimum working voltage of the high-voltage battery is 270V, and the preset voltage can be less than 270V. The preset voltage can be set according to actual needs under the premise of being lower than the minimum working voltage of the high-voltage battery. For example, if it is expected that the limp mode is quickly switched to the normal mode, the preset voltage can be set relatively high, which can reduce the time required for the motor-side voltage to drop below the preset voltage, thereby speeding up the switching from the limp mode to the normal mode. If it is expected that the limp mode is slowly switched to the normal mode, the preset voltage can be set relatively low, which can lengthen the time required for the motor-side voltage to drop below the preset voltage, thereby prolonging the time from the limp mode to the normal mode. The setting of the preset voltage makes the time from the limp mode to the normal mode controllable, which can be adjusted according to actual needs to balance the response speed and system stability.

[0077] It can be understood that the voltage difference between the two sides of the pre-charge relay generally does not affect the safe closing of the pre-charge relay. In the related art, the pre-charge relay can be safely controlled to close even if there is a large voltage difference between the two sides. For example, the voltage difference between the two sides of the pre-charge relay can be very large. The low-voltage side (such as the motor side) can be below 60V, and the high-voltage side (such as the high-voltage battery side) can reach several hundred volts (for example, 300V to 400V). Although the voltage difference between the two sides of the pre-charge relay is large in this case, it does not affect the safe closing of the pre-charge relay.

[0078] In a possible implementation, after the motor stops generating electricity, the method further includes: starting timing from the time when the motor stops generating electricity to obtain a timing duration; and after the timing duration reaches a first preset duration, controlling the high-to-low voltage device to exit the voltage reduction state.

[0079] The first preset time length can be preset, such as 1 second, aiming to prolong the time length of the high-to-low voltage device in the voltage reduction state, so that even if the motor stops generating electricity, the high-to-low voltage device can continue to serve as a load of the motor, consume the residual electricity after the motor stops generating electricity, and make the voltage of the residual electricity after the motor stops generating electricity drop to below the preset voltage as soon as possible. For example, if the high-to-low voltage device exits the voltage reduction state and enters the standby state immediately after the motor stops generating electricity, the motor-side voltage is in a natural drop process, and it may take 20 seconds for the motor-side voltage to drop to 30V. However, if the high-to-low voltage device delays for the first preset time length before exiting the voltage reduction state after the motor stops generating electricity, the motor-side voltage will be in a rapid drop process, and it may only take 1 second for the motor-side voltage to drop to 30V, thereby accelerating the drop rate of the motor-side voltage. It should be noted that the above-mentioned 30V, 20 seconds, 1 second and other numerical values are examples for the purpose of understanding and are not limited in specific implementation.

[0080] The high-to-low voltage device is controlled to exit the voltage reduction state, that is, to enter the standby state. After the high-to-low voltage device enters the standby state, the high-to-low voltage device has no power demand and is in a state without high-voltage electricity, so it will not consume the high-voltage electricity generated by the motor or the residual electricity after the motor stops generating electricity.

[0081] Optionally, the first preset time length can be set with reference to the preset voltage. For example, the smaller the preset voltage, the more the motor-side voltage needs to drop, and the longer the first preset time length can be set to, so that the high-to-low voltage device can exit the voltage reduction state for a longer time, which is conducive to consuming more motor-side voltage and making the motor-side voltage drop faster. The larger the preset voltage, the less the motor-side voltage needs to drop, and the shorter the first preset time length can be set to, so that the high-to-low voltage device can exit the voltage reduction state for a shorter time, which can also meet the requirement of the motor-side voltage drop.

[0082] In the above implementation, after the motor stops generating electricity, the high-to-low voltage device is controlled to exit the voltage reduction state after a delay. After the motor stops generating electricity, the motor-side voltage starts to drop. By controlling the high-to-low voltage device to exit the voltage reduction state after the first preset time length, the high-to-low voltage device can continue to serve as a load of the motor for the first preset time length, so as to continue to consume the residual electricity after the motor stops generating electricity, which is conducive to accelerating the drop rate of the motor-side voltage and making the motor-side voltage drop rapidly to less than or equal to the preset voltage, so as to meet the condition of closing the pre-charging relay as soon as possible, which is conducive to shortening the time length required for closing the pre-charging relay after the motor stops generating electricity and accelerating the speed of switching the vehicle from the limp-home mode to the normal mode.

[0083] In a specific implementation, after the high-to-low voltage device exits the voltage reduction state, the low-voltage system can be powered by a small battery system (for example, a 12V battery system) to meet basic power supply requirements.

[0084] In another possible implementation, after the motor stops generating electricity, the method further includes: controlling the high-to-low voltage device to exit the voltage reduction state and delaying sending of the closing instruction of the pre-charging relay for a second preset time period; and in response to detecting that the motor-side voltage drops to be less than or equal to the preset voltage, controlling the pre-charging relay of the high-voltage battery to be closed, including: in response to detecting that the motor-side voltage drops to be less than or equal to the preset voltage, controlling the pre-charging relay of the high-voltage battery to be closed based on the closing instruction.

[0085] In this implementation, after the motor stops generating electricity, the high-to-low voltage device does not exit the voltage reduction state with a delay, that is, the voltage reduction function of the high-to-low voltage device is not stopped with a delay, but the closing instruction of the pre-charging relay is sent with a delay, that is, after the motor stops generating electricity, the closing instruction of the pre-charging relay is sent after a second preset time period. In this case, it is equivalent to waiting for the motor-side voltage to naturally drop under no load, so that during the process of natural drop of the motor-side voltage, in response to detecting that the motor-side voltage drops to be less than or equal to the preset voltage, the pre-charging relay of the high-voltage battery is controlled to be closed based on the closing instruction.

[0086] The second preset time period can be preset, for example, set with reference to a time period required for the motor-side voltage to naturally drop to the preset voltage. The second preset time period can be greater than or equal to a time period required for the motor-side voltage to naturally drop to the preset voltage after the motor stops generating electricity, so that when the motor-side voltage drops to be less than or equal to the preset voltage, the pre-charging relay of the high-voltage battery can be controlled to be closed based on the closing instruction.

[0087] In a specific implementation, the second preset time period is generally greater than the first preset time period.

[0088] In the above implementation, after the motor stops generating electricity, the high-voltage-to-low-voltage device is controlled to exit the voltage reduction state without delay, and the closing instruction of the pre-charge relay is sent after a second preset time delay, so as to ensure that the motor-side voltage stably decreases to be lower than the preset voltage, thereby avoiding false fault reporting of the control system and improving the reliability and stability of the system. It can be understood that after the high-voltage-to-low-voltage device exits the voltage reduction state, the motor is equivalent to losing the load of the high-voltage-to-low-voltage device, so that the decrease speed of the motor-side voltage becomes slow. It takes a certain time for the motor-side voltage to decrease to be less than or equal to the preset voltage, and by sending the closing instruction of the pre-charge relay after a second preset time delay, it is beneficial to make the control system know that the waiting time is actually waiting for the closing instruction of the pre-charge relay, rather than operation delay due to other unknown reasons, which helps to avoid false fault reporting of the control system due to unknown waiting, and improves the reliability and stability of the system.

[0089] In step 104, after the pre-charge relay is closed, the pre-charge circuit is turned on, so that the motor-side voltage starts to rise. In the process of rising of the motor-side voltage, it is detected whether the absolute value of the voltage difference between the motor-side voltage and the high-voltage battery-side voltage is less than a preset voltage difference value. If it is detected that the absolute value of the voltage difference between the motor-side voltage and the high-voltage battery-side voltage is less than the preset voltage difference value, the main relay is controlled to be closed, and the pre-charge relay is controlled to be opened, so as to switch from the limp-home mode to the normal mode. The voltage difference between the motor-side voltage and the high-voltage battery-side voltage is the voltage difference on both sides of the main relay, and the voltage difference on both sides of the main positive relay is basically the same as the voltage difference on both sides of the main negative relay. The embodiment is described by taking the voltage difference on both sides of the main positive relay 202 shown in FIG. 2 as an example. Figure 2

[0090] Referring to FIG. 2, Figure 2 the voltage difference on both sides of the main positive relay 202 is: the voltage difference between the high-voltage battery-side voltage and the motor-side voltage. The high-voltage battery-side voltage is the voltage between the positive electrode of the high-voltage battery 201 and the first end of the main positive relay 202 in Figure 2 , such as the voltage between points a and b in the figure. The motor-side voltage is the voltage between one side of the motor 206 and the second end of the main positive relay 202 in Figure 2 , such as the voltage between points c and d in the figure.

[0091] ​In a specific implementation, the high-voltage battery side voltage and the motor side voltage can be measured by using voltage sensors, and the voltage difference between the high-voltage battery side voltage and the motor side voltage can be calculated by the control system, and the absolute value of the voltage difference is taken as the voltage difference in step 104. Then, it is determined whether the absolute value of the voltage difference between the two sides of the relay is less than a preset voltage difference value. The preset voltage difference value can be a safety voltage difference threshold calibrated in advance, which aims to measure whether the voltage difference between the two sides of the main relay is close enough, close enough to the closure of the relay that the voltage difference will not affect the safety of the relay. For example, if the motor side voltage is equal to 100% ± 5% of the high-voltage battery side voltage, it can be determined whether the voltage difference between the two sides of the main relay is less than the preset voltage difference value. The ± 5% can be calibrated in advance, or can be calibrated to ± 2% or ± 10%, and the present embodiment does not make specific limitations.

[0092] In the case where the absolute value of the voltage difference between the motor side voltage and the high-voltage battery side voltage is less than the preset voltage difference value, the control system issues a main relay closing instruction to close the main relay and reestablish the connection between the high-voltage battery and the electrical system. It can be understood that the main relay of the high-voltage battery includes a main positive relay and a main negative relay. In order to reestablish the connection between the high-voltage battery and the electrical system, the main positive relay and the main negative relay need to be closed. After closing the main positive relay and the main negative relay, the pre-charge relay is controlled to be disconnected.

[0093] In a possible implementation, when switching the vehicle from the limp-home mode to the normal mode, the size of the vehicle speed can also be considered. If the vehicle speed is lower than a preset vehicle speed threshold, the vehicle is switched from the limp-home mode to the normal mode, so as to improve the safety of mode switching to a certain extent. The preset vehicle speed threshold can be calibrated in advance, for example, it can be set to 130 km / h, or it can be set to 60 km / h, but the present embodiment does not make specific limitations. In the normal mode, the vehicle is powered by the high-voltage battery.

[0094] In the above implementation, after the vehicle enters the limp-home mode, the compressor is controlled to be in a power adjustable state or an inhibited state without power demand, and after the vehicle returns to the normal mode, the high-voltage battery can work normally, so the working state of the compressor can be restored. Based on this, in a possible implementation, after the vehicle is switched from the limp-home mode to the normal mode, the state of the compressor is set to a power adjustable state, and the power demand of the compressor is allowed to be greater than 0; or the state of the compressor is set to a normal state; wherein in the normal state, the compressor is allowed to work normally.

[0095] The power demand of the compressor being greater than 0 can be understood as that the control system allows the power request value of the compressor to be greater than 0, and will apply the rotating torque to the compressor according to the power request value of the compressor. That is, the control system dynamically adjusts the power output of the compressor by adjusting the rotating torque of the motor of the compressor according to the actual power demand, so as to meet the required refrigeration or heating demand. Since the state of the compressor is the power adjustable state at this time, although the compressor has a power demand, the compressor is still controlled to operate in a limited power mode, that is, the control system still limits the maximum operating power of the compressor to avoid the actual operating power of the compressor exceeding the maximum operating power.

[0096] If the state of the compressor is set to the normal state, the control system can control the compressor according to the power request of the compressor without power limitation.

[0097] In the above implementation, after the vehicle returns to the normal mode, the high-voltage battery can work normally, and therefore setting the state of the compressor to the power adjustable state and allowing the power demand of the compressor to be greater than 0, or setting the state of the compressor to the normal state, is beneficial to timely resuming the work of the compressor to realize the functions related to the compressor such as starting the air conditioner and starting the heater.

[0098] In some implementations, after the step 104, the method further includes: activating a target flag bit if the current gear of the vehicle is a driving gear and the remaining amount of the high-voltage battery is greater than a preset amount threshold; wherein the target flag bit represents that the vehicle has switched to the normal mode; and in the case that the target flag bit is activated, the high-voltage battery is allowed to supply power to the high-voltage electrical equipment, and the motor is allowed to participate in the driving of the vehicle.

[0099] The current gear of the vehicle is the driving gear, which indicates that the vehicle is currently in the driving process, and the remaining amount of the high-voltage battery being greater than the preset amount threshold indicates that the current remaining amount of the high-voltage battery is sufficient to meet the power supply demand of the high-voltage system, and therefore the target flag bit is activated. Each subsystem in the vehicle can monitor the message that the target flag bit is activated, to clearly indicate that the high-voltage battery is currently allowed to supply power to the high-voltage electrical equipment, and the motor is allowed to participate in the driving of the vehicle. In the case that the target flag bit is activated, the control system allows the high-voltage battery to supply power to the high-voltage electrical equipment (such as the air conditioner compressor, the heater, the high-voltage to low-voltage device, etc.), and allows the motor to participate in the driving of the vehicle. This means that the vehicle can fully utilize the energy of the high-voltage battery to restore the normal working performance. The driver can immediately feel that the vehicle has returned to the normal mode and all functions are available without worrying about any potential function limitation or delay. The preset amount threshold can be pre-calibrated to measure whether the remaining amount of the high-voltage battery pack is sufficient.

[0100] It can be understood that although the vehicle has recovered from the limp mode to the normal mode, various controllers (such as the motor controller, the vehicle controller, etc.) / subsystems (such as the power management system, the air conditioning system, etc.) in the vehicle can not have received the notification of the change. Without taking measures, these controllers can mistakenly believe that the high-voltage battery has not recovered to normal or the motor cannot normally drive the vehicle, resulting in unnecessary restrictions or errors. By activating the target flag, the control system can explicitly send a signal to the various controllers / subsystems of the vehicle, informing them that the high-voltage battery has recovered to normal power supply capability and the motor has normal driving function. This helps to ensure that the controllers / subsystems can update their working status in time, avoiding misjudgment or delayed response due to information asynchronization. In particular, it helps the motor controller to know that the motor can currently drive the vehicle, so that the motor controller can normally control the motor output driving torque based on the received driving torque request.

[0101] The introduction of the target flag enhances the coordination between the vehicle controllers. As a global state identifier, the target flag enables each subsystem to reach a consistent understanding at the same time point, ensuring that all controllers can obtain the latest state information in time, avoiding operation errors or resource waste due to information asymmetry, and significantly improving the safety and stability of the entire system. Each subsystem can make the most appropriate response based on the latest state information, improving the vehicle's ability to respond to unexpected situations.

[0102] Figure 5 is a schematic diagram of the principle of activating the target flag in this embodiment. As shown in Figure 5 If the current gear of the vehicle is the driving gear, the voltage of the high-voltage battery is within the normal voltage range, the remaining capacity of the high-voltage battery is greater than the preset capacity threshold, the main positive relay is closed, the main negative relay is closed, and the high-voltage battery has no fault, the target flag can be activated. The activation of the target flag also indicates that the high-voltage battery is currently supplying power to the vehicle. After the target flag is activated, the torque demand of the control system for the motor can be realized in steps to enable the motor to participate in the driving of the vehicle. At the same time, the high-voltage battery can supply power to the high-voltage-to-low-voltage device, the compressor, and other high-voltage electrical equipment.

[0103] The above technical solution, by activating the target flag, the control system can explicitly inform each subsystem that the high-voltage battery has recovered to normal power supply capability and the motor has normal driving function. This not only avoids misjudgment or delayed response due to information asynchronization, but also improves the overall efficiency and safety of the system, ensuring the consistency and reliability of the driving experience.

[0104] In some implementations, in the case of elimination of the abnormality of the high-voltage battery, if the vehicle is not detected to switch from the limp-home mode to the normal mode within a third preset time length, the vehicle is switched back to the limp-home mode

[0105] After the abnormality of the high-voltage battery is eliminated, the vehicle should theoretically switch from the limp-home mode to the normal mode. However, due to the presence of other unforeseen problems (such as leakage, poor earthing, virtual connection, etc.), the vehicle fails to complete this switching within the expected time. Based on this, a reasonable third preset time length is defined in this embodiment, which is based on the maximum time required for the vehicle to switch from the limp-home mode to the normal mode under normal circumstances after the abnormality of the high-voltage battery is eliminated. For example, if the switching process should not exceed 30 seconds under normal circumstances, the third preset time length can be set to 45 seconds to leave a certain buffer time. If the control system fails to detect that the vehicle successfully switches from the limp-home mode to the normal mode within the above-mentioned third preset time length, the system will automatically switch the vehicle back to the limp-home mode. Through this mechanism, even if the high-voltage battery returns to normal, but due to other reasons, the vehicle is still in a relatively safe state when it fails to switch to the normal mode smoothly, avoiding potential risks.

[0106] In summary, in this embodiment, when the hybrid vehicle is in the limp-home mode, after the high-voltage battery recovers from the abnormality, it automatically switches to the state of being supplied by the normal high-voltage battery during driving, which not only ensures the safety of the vehicle, but also does not affect the driving experience. This not only improves the reliability and user-friendliness of the vehicle, but also enhances the adaptability of the vehicle under different working conditions.

[0107] Figure 6 FIG. 1 is a structural schematic diagram of a vehicle control device provided by an embodiment of the present application.

[0108] For example, as shown in FIG. 6, the vehicle control device 600 includes: Figure 6

[0109] The limp-home control module 601 is configured to control the vehicle to enter the limp-home mode if it is detected that the high-voltage battery is abnormal during driving of the vehicle. In the limp-home mode, the main relay of the high-voltage battery is disconnected, the engine drives the vehicle to run, and the engine drives the motor to rotate and generate electricity.

[0110] The motor control module 602 is configured to control the motor to stop generating electricity if it is detected that the abnormality of the high-voltage battery is eliminated in the limp-home mode.

[0111] The pre-charging relay control module 603 is configured to control the pre-charging relay of the high-voltage battery to be closed if it is detected that the motor-side voltage drops to be less than or equal to a preset voltage after the motor stops generating electricity. The preset voltage is lower than the minimum working voltage of the high-voltage battery.​

[0112] The mode switching control module 604 is configured to, after the pre-charging relay is closed, if it is detected that an absolute value of a voltage difference between the motor-side voltage and the high-voltage battery-side voltage is less than a preset voltage difference value, control the main relay to be closed and control the pre-charging relay to be disconnected, so that the vehicle is switched from the limp-home mode to a normal mode.

[0113] In a possible implementation, the vehicle control apparatus further includes a high-to-low voltage device module configured to, before the abnormality of the high-voltage battery is eliminated, control a high-to-low voltage device of the vehicle to enter a step-down state, and in the step-down state, control the high-to-low voltage device to perform step-down processing on a generated voltage of the motor to supply power to a low-voltage system of the vehicle.

[0114] In a possible implementation, in the limp-home mode, a maximum generated voltage of the motor is a first target voltage, and the first target voltage is greater than or equal to a rated voltage of the high-voltage battery; and the high-to-low voltage device module is specifically configured to: detect a generated voltage of the motor in a generating process; and if the generated voltage is greater than a preset voltage threshold and less than a second target voltage, control the high-to-low voltage device to start entering the step-down state, where the second target voltage is less than or equal to the first target voltage.

[0115] In a possible implementation, the high-to-low voltage device module is further configured to: after the motor stops generating electricity, start timing from a time when the motor stops generating electricity to obtain a timing duration; and after the timing duration reaches a first preset duration, control the high-to-low voltage device to exit the step-down state.

[0116] In a possible implementation, the high-to-low voltage device module is further configured to: after the motor stops generating electricity, control the high-to-low voltage device to exit the step-down state, and delay sending a closing instruction of the pre-charging relay for a second preset duration; and the pre-charging relay control module 603 is specifically configured to: if it is detected that the motor-side voltage drops to be less than or equal to a preset voltage, control a pre-charging relay of the high-voltage battery to be closed based on the closing instruction.

[0117] In a possible implementation, the vehicle control apparatus further includes a compressor control module configured to, after the vehicle enters the limp-home mode, the method further includes: setting a state of a compressor of an air conditioning system of the vehicle to a power-adjustable state, and controlling a power demand of the compressor to be 0; or setting the state of the compressor of the air conditioning system of the vehicle to a prohibited state; and in the prohibited state, the compressor is prohibited from working.

[0118] In one possible implementation, the compressor control module is further used to: after the vehicle switches from the limp mode to the normal mode, set the state of the compressor to a power-adjustable state and allow the power demand of the compressor to be greater than 0; or; set the state of the compressor to a normal state; wherein, in the normal state, the compressor is allowed to operate normally.

[0119] In one possible implementation, the vehicle control device also includes: a flag activation module, which is used to activate a target flag after controlling the main relay to close and the pre-charge relay to disconnect so that the vehicle switches from the limp mode to the normal mode, if the current gear of the vehicle is a driving gear and the remaining power of the high-voltage battery is greater than a preset power threshold; wherein the target flag indicates that the vehicle has switched to the normal mode; when the target flag is activated, the high-voltage battery is allowed to supply power to high-voltage electrical equipment, and the motor is allowed to participate in driving the vehicle.

[0120] In one possible implementation, the mode switching control module 604 is further configured to, when the abnormality of the high-voltage battery is eliminated, switch the vehicle back to the limp mode if the vehicle is not detected switching from the limp mode to the normal mode within a third preset time period.

[0121] Figure 7 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0122] For example, Figure 7 As shown, the vehicle 700 includes: a memory 701 and a processor 702, wherein the memory 701 stores an executable program code 7011, and the processor 702 is used to call and execute the executable program code 7011 to perform a vehicle control method.

[0123] In addition, an embodiment of the present application also protects a device, which may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to perform a vehicle control method provided by an embodiment of the present application.

[0124] In this embodiment, the device can be divided into functional modules based on the above-described method examples. For example, each functional module can be mapped to a specific functional module, 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 a logical functional division. In actual implementation, other division methods may be used.

[0125] In the case of adopting the respective functional modules corresponding to the respective functions, the apparatus can further include a first control module, a first detection module, a second detection module, a second control module, and the like. It should be noted that all related content of the respective steps involved in the above method embodiments can be referred to the function description of the corresponding functional modules, and will not be repeated here.

[0126] It should be understood that the apparatus provided by the embodiments is used to execute the above-mentioned vehicle control method, and thus can achieve the same effects as the above-mentioned implementation method.

[0127] In the case of adopting the integrated unit, the apparatus can include a processing module, a storage module. When the apparatus is applied to a vehicle, the processing module can be used to control and manage the actions of the vehicle. The storage module can be used to support the vehicle to execute the related program code and the like.

[0128] The processing module can be a processor or a controller, which can realize or execute various exemplary logical blocks, modules and circuits shown in combination with the disclosure of the present application. The processor can also be a combination of computing functions, such as including one or more microprocessor combinations, digital signal processing (DSP) and microprocessor combinations, and the like. The storage module can be a memory.

[0129] In addition, the apparatus provided by the embodiments of the present application can be a chip, a component or a module, the chip can include a connected processor and a memory; wherein the memory is used to store instructions, when the processor calls and executes the instructions, the chip can execute the above-mentioned vehicle control method provided by the embodiments.

[0130] The embodiments also provide a computer readable storage medium, which stores computer program codes, when the computer program codes run on a computer, the computer executes the above-mentioned related method steps to realize the above-mentioned vehicle control method provided by the embodiments.

[0131] The embodiments also provide a computer program product, when the computer program product runs on a computer, the computer executes the above-mentioned related steps to realize the above-mentioned vehicle control method provided by the embodiments.

[0132] The apparatus, computer readable storage medium, computer program product or chip provided by the embodiments are used to execute the corresponding method provided above, and thus the beneficial effects that can be achieved can refer to the beneficial effects of the corresponding method provided above, and will not be repeated here.

[0133] Through the description of the above embodiments, those skilled in the art can understand that, for the convenience and brevity of description, only the division of the above functional modules is exemplified, and in actual application, the above functions can be completed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above.

[0134] In the embodiments provided in the present application, it should be understood that the disclosed device and method can be implemented in other ways. For example, the device embodiments described above are only illustrative, for example, the division of the modules or units is only a logical function division, and in actual implementation, there can be another division manner, for example, a plurality of units or components can be combined or integrated into another device, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed ones can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0135] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method of vehicle control, characterized by, The method comprises: During driving of the vehicle, if an abnormality of the high-voltage battery is detected, the vehicle is controlled to enter a limp-home mode; wherein in the limp-home mode, a main relay of the high-voltage battery is disconnected, the engine drives the vehicle to drive and the engine drives the motor to rotate and generate electricity; The high-voltage-to-low-voltage device of the vehicle is controlled to enter a voltage reduction state; In the voltage reduction state, the high-voltage-to-low-voltage device is controlled to reduce the voltage generated by the motor to supply power to the low-voltage system of the vehicle; In the limp-home mode, if the abnormality of the high-voltage battery is eliminated, the motor is controlled to stop generating electricity; After the motor stops generating electricity, the high-voltage-to-low-voltage device is controlled to exit the voltage reduction state, and a closing instruction of a pre-charging relay is sent after a second preset time period; if it is detected that the voltage on the motor side drops to less than or equal to a preset voltage, the pre-charging relay of the high-voltage battery is controlled to close based on the closing instruction; wherein the preset voltage is lower than the minimum working voltage of the high-voltage battery; After the pre-charging relay is closed, if it is detected that the absolute value of the voltage difference between the voltage on the motor side and the voltage on the high-voltage battery side is less than a preset voltage difference value, the main relay is controlled to close and the pre-charging relay is controlled to disconnect, so that the vehicle is switched from the limp-home mode to a normal mode.

2. The method of claim 1, wherein, In the limp-home mode, the maximum voltage generated by the motor is a first target voltage, and the first target voltage is greater than or equal to the rated voltage of the high-voltage battery; The control of the high-voltage-to-low-voltage device of the vehicle to enter the voltage reduction state comprises: Detecting the voltage generated by the motor during electricity generation; If the voltage generated is greater than a preset voltage threshold and less than a second target voltage, the high-voltage-to-low-voltage device is controlled to start entering the voltage reduction state; wherein the second target voltage is less than or equal to the first target voltage.

3. The method of claim 1, wherein, After the motor stops generating electricity, the method further comprises: Timing from the time when the motor stops generating electricity to obtain a timing duration; After the timing duration reaches a first preset time period, the high-voltage-to-low-voltage device is controlled to exit the voltage reduction state.

4. The method of claim 1, wherein, After the vehicle is controlled to enter the limp-home mode, the method further comprises: Setting the state of the compressor of the air conditioning system of the vehicle to a power-adjustable state, and controlling the power demand of the compressor to be 0; Or; Setting the state of the compressor of the air conditioning system of the vehicle to a prohibited state; wherein in the prohibited state, the compressor is prohibited from working.

5. The method of claim 4, wherein, After the vehicle is switched from the limp-home mode to the normal mode, the method further comprises: Setting the state of the compressor to a power-adjustable state, and allowing the power demand of the compressor to be greater than 0; Or; Setting the state of the compressor to a normal state; wherein in the normal state, the compressor is allowed to work normally.

6. The method of claim 1, wherein, After the main relay is controlled to close and the pre-charging relay is controlled to disconnect, so that the vehicle is switched from the limp-home mode to the normal mode, the method further comprises: If the current gear of the vehicle is a driving gear and the residual capacity of the high-voltage battery is greater than a preset capacity threshold, a target flag is activated, wherein the target flag represents that the vehicle has switched to the normal mode; In a case where the target flag is activated, the high-voltage battery is allowed to supply power to high-voltage electrical equipment, and the motor is allowed to participate in driving of the vehicle.

7. The method of claim 1, wherein, In a case where the abnormality of the high-voltage battery is eliminated, the method further comprises: If the vehicle is not detected to switch from the limp-home mode to the normal mode within a third preset time length, the vehicle is switched back to the limp-home mode.

8. A vehicle characterized by comprising: The vehicle comprises: a memory for storing executable program code; a processor for calling and running the executable program code from the memory, so that the vehicle executes the method according to any one of claims 1 to 7.

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