Vehicle control method and vehicle

Abstract

The invention provides a vehicle control method and a vehicle, the method is applied to the field of vehicles, and the method comprises the steps that in the vehicle driving process, if it is detected that a high-voltage battery is abnormal, the vehicle is controlled to enter a limping mode; in the limping mode, if it is detected that the abnormity of the high-voltage battery is eliminated, the motor is controlled to stop generating power; after the motor stops generating power, if it is detected that the motor side voltage is reduced to be smaller than or equal to the preset voltage, a pre-charging relay of the high-voltage battery is controlled to be closed; the preset voltage is lower than the lowest working voltage of the high-voltage battery; and 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 smaller than a 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. According to the method, the high-voltage battery can be safely and conveniently started to be switched to the normal mode after the abnormity of the high-voltage battery is eliminated in the limping 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 hybrid vehicle is driving and the high-voltage battery fails, the vehicle will enter limp mode to maintain basic driving functions. In limp 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 eliminated by itself during subsequent driving, it is usually not allowed to directly enable the high-voltage battery. Instead, the driver is required to stop and restart the vehicle to re-enable the high-voltage battery, which increases the burden and inconvenience of driving. Based on this, how to safely and conveniently enable the high-voltage battery in limp mode to switch to normal mode has become a technical problem that needs to be solved urgently. Summary of the invention

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

[0004] In a first aspect, a vehicle control method 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 mode; wherein, in the limp 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 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 a preset voltage, the pre-charge relay of the high-voltage battery is controlled 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 the preset voltage difference, the main relay is controlled to close, and the pre-charge relay is controlled to disconnect, so that the vehicle switches from the limp mode to the normal mode.

[0005] In the above technical solution, if an abnormality of the high-voltage battery is detected during the driving of the vehicle, the vehicle is controlled to enter the limp mode to ensure that the vehicle can continue to drive safely when the high-voltage battery fails, avoiding the vehicle from completely losing power due to power supply interruption. The engine drives the motor to rotate and generate electricity, ensuring the continuous operation of the basic functions of the vehicle. In the limp mode, if the abnormality of the high-voltage battery is detected to be eliminated, it means that there are conditions for re-enabling the high-voltage battery. At this time, the motor is controlled to stop generating electricity to provide preparation conditions for switching to normal mode. After the motor stops generating electricity, the voltage on the motor side 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 the preset voltage, the pre-charge relay is controlled to close. After the pre-charge relay is closed, the motor side voltage will be further pulled up. As the motor side voltage increases, 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 to avoid the main relay burning problem that may occur when the main relay is directly closed due to excessive voltage difference. In addition, since the preset voltage is lower than the minimum operating 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 operating voltage of the high-voltage battery, 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, thereby 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, providing a safe condition for closing the main relay. At the same time, the driver does not need to stop the car during the entire process, reducing unnecessary parking and restarting operations, and improving driving convenience and comfort.

[0006] In combination with the first aspect, in certain possible implementations, before the abnormality of the high-voltage battery is eliminated, the method also includes: controlling the high-voltage to low-voltage device of the vehicle 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 low-voltage system of the vehicle.

[0007] In the above technical solution, before the abnormality of the high-voltage battery is eliminated, the high-voltage battery cannot generate high-voltage electricity, and the high-voltage to low-voltage device is controlled to enter the voltage reduction state to meet the power supply demand of the vehicle's low-voltage system. In addition, the high-voltage to low-voltage device in the voltage reduction state can act as a load for the motor to restrict the rapid rise of the generated voltage, ensuring that the motor generated voltage is maintained within a safe and controllable range, and avoiding excessively high motor generated voltage.

[0008] In combination with the first aspect and the above-mentioned implementation methods, in certain possible implementation methods, in the limp 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; the high-voltage to low-voltage device of the vehicle is controlled to enter a voltage reduction state, including: detecting the power generation voltage of the motor during the power generation process; if the power generation voltage is greater than a preset voltage threshold and less than a second target voltage, controlling the high-voltage to low-voltage device to start entering a voltage reduction state; wherein the second target voltage is less than or equal to the first target voltage.

[0009] The above technical solution, in limp mode, by setting a higher first target voltage, provides a longer voltage range for the high-voltage to low-voltage device to restrict the rapid rise of the motor's power generation voltage. When the power generation voltage is greater than the preset voltage threshold and less than the second target voltage, the high-voltage to low-voltage device is controlled to enter the step-down state, which is equivalent to avoiding the stage where the motor power generation voltage changes rapidly (the stage when power generation just begins and the stage when the maximum power generation voltage is about to be reached). If the power generation voltage changes too quickly, it may cause the high-voltage to low-voltage device to enter the step-down state, and it is difficult to restrict the rapidly rising motor power generation voltage. When the power generation voltage is between the preset voltage threshold and the second target voltage, the power generation voltage changes relatively slowly, so it is easier to control the power generation voltage by controlling the high-voltage to low-voltage device to enter the step-down state during this period. Combined with the dynamic monitoring of the power generation voltage, timely control of the high-voltage to low-voltage device to enter the step-down state to power the low-voltage system not only avoids the risks that may be caused by the excessively high power generation voltage of the motor, but also ensures the stable power supply of the low-voltage system, effectively realizes the safe management of the motor power generation voltage, and also improves the safety and reliability of the vehicle.

[0010] In combination with the first aspect and the above-mentioned implementation method, after the motor stops generating electricity, it also includes: starting timing from the moment the motor stops generating electricity to obtain a timing duration; after the timing duration reaches a first preset duration, controlling the high-voltage to low-voltage device to exit the voltage reduction state.

[0011] The above technical solution controls the high-voltage to low-voltage device to delay exiting the step-down state after the motor stops generating electricity. After the motor stops generating electricity, the voltage on the motor side begins to drop. By controlling the high-voltage to low-voltage device to exit the step-down state after the first preset time, the high-voltage to low-voltage device can continue to serve as the load of the motor within the first preset time to continue to consume the residual electricity remaining after the motor stops generating electricity. This is conducive to accelerating the rate of decrease of the voltage on the motor side, so that the voltage on the motor side quickly drops to less than or equal to the preset voltage, so as to meet the conditions for closing the pre-charging relay as soon as possible. This is conducive to shortening the time required to close the pre-charging relay after the motor stops generating electricity, and accelerating the speed at which the vehicle switches from limp mode to normal mode.

[0012] In combination with the first aspect and the above-mentioned implementation methods, in certain possible implementation methods, after the motor stops generating electricity, the method further includes: controlling the high-voltage to low-voltage device to exit the voltage reduction state, and delaying the second preset time to send a closing instruction for the pre-charging relay; if it is detected that the voltage on the motor side drops to less than or equal to the preset voltage, controlling the pre-charging relay of the high-voltage battery to close, including: if it is detected that the voltage on the motor side drops to less than or equal to the preset voltage, controlling the pre-charging relay of the high-voltage battery to close based on the closing instruction.

[0013] The above technical solution, after the motor stops generating electricity, controls the high-voltage to low-voltage device to exit the step-down state without delay, and delays the second preset time to send the closing instruction of the pre-charging relay, which can ensure that the voltage on the motor side steadily drops to below the preset voltage, which not only avoids the control system from falsely reporting faults, but also improves the reliability and stability of the system. It can be understood that after the high-voltage to low-voltage device exits the step-down state, the motor is equivalent to losing the load of the high-voltage to low-voltage device, so the rate of decrease of the voltage on the motor side will become slow. It takes a certain amount of time to wait for the motor side voltage to drop to less than or equal to the preset voltage. By delaying the second preset time to send the closing instruction of the pre-charging relay, it is beneficial to let the control system know that the waiting time is actually waiting for the closing instruction of the pre-charging relay, rather than the operation delay caused by other unknown reasons, which helps to avoid the control system from falsely reporting faults due to waiting for unknown reasons, and improve the reliability and stability of the system.

[0014] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, after controlling the vehicle to enter the limp home mode, the method further includes: setting the state of the compressor of the vehicle's air-conditioning system to a power-adjustable state, and controlling the power demand of the compressor to 0; or; setting the state of the compressor of the vehicle's air-conditioning system to a prohibited state; wherein, in the prohibited state, the compressor is prohibited from operating.

[0015] In the above technical solution, after the vehicle enters the limp home mode, the state of the compressor is set to the power adjustable state, and the power demand of the compressor is controlled to 0; or; the state of the compressor is set to the disabled state, which can save the electric energy generated by the motor for more critical driving functions, and avoid the compressor as a load on the motor, affecting the stable output of the motor's power generation voltage. Setting the compressor to the power adjustable state and ensuring that it has no power demand is actually an energy-saving measure achieved through flexible control logic. Even when power is limited, the compressor is still able to start at any time to cope with sudden temperature control needs.

[0016] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, after the vehicle switches from the limp mode to the normal mode, the method further includes: 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 operate normally.

[0017] In the above technical solution, after the vehicle returns to normal mode, the high-voltage battery can work normally. Therefore, the state of the compressor is set to an adjustable power 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, which is conducive to timely restoring the operation of the compressor to realize functions related to the compressor such as turning on the air conditioner and turning on the heater.

[0018] In combination with the first aspect and the above-mentioned implementation methods, in certain possible implementation methods, after controlling the main relay to close and controlling the pre-charge relay to disconnect so that the vehicle switches from the limp 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 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.

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

[0020] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, when the abnormality of the high-voltage battery is eliminated, the method also includes: if the vehicle is not detected to switch from the limp mode to the normal mode within a third preset time period, switching the vehicle back to the limp mode.

[0021] The above technical solution ensures that even if the high-voltage battery returns to normal but cannot switch to normal mode smoothly due to other reasons, the vehicle remains in a relatively safe state to avoid potential risks.

[0022] In a second aspect, a vehicle control device is provided, which includes: a limp home control module, for controlling the vehicle to enter a limp home mode if an abnormality is detected in a high-voltage battery during vehicle driving; 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; a motor control module, for controlling the motor to stop generating electricity in the limp home mode if the abnormality of the high-voltage battery is detected to be eliminated; a pre-charge relay control module, for controlling the pre-charge relay of the high-voltage battery to close if it is detected that the motor side voltage drops to less than or equal to a preset voltage after the motor stops generating electricity; wherein, the preset voltage is lower than the minimum operating voltage of the high-voltage battery; a mode switching control module, for controlling the main relay to close and the pre-charge relay to disconnect 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 after the pre-charge relay is closed, so that the vehicle switches from the limp home mode to the normal mode.

[0023] In a third aspect, a vehicle is provided, comprising: a memory for storing executable program code; and a processor for calling and running the executable program code from the memory, so that the vehicle executes the method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0024] In a fourth aspect, a computer program product is provided, comprising: a computer program code, which, when executed on a computer, enables the computer to execute the method in the first aspect or any possible implementation of the first aspect.

[0025] 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 method in the above-mentioned first aspect or any possible implementation manner of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic flow chart of a vehicle control method provided in an embodiment of the present application;

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

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

[0029] Figure 4This is a schematic diagram of the relationship between the power generation voltage and time after a motor starts to generate power, provided in an embodiment of the present application;

[0030] Figure 5 This is a schematic diagram of the principle of activating a target flag provided in an embodiment of the present application;

[0031] Figure 6 is a structural schematic diagram of a vehicle control device provided in an embodiment of the present application;

[0032] Figure 7 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present 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 the present application, "multiple" means two or more than two.

[0034] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0035] When a hybrid vehicle is driving and the high-voltage battery fails, the vehicle will enter limp mode to maintain basic driving functions. In limp 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 eliminated by itself during subsequent driving, the vehicle cannot be switched to high-voltage battery drive because it is in driving, that is, the vehicle cannot be driven electrically. In other words, if the high-voltage battery failure is restored during driving in limp mode, the high-voltage battery power cannot be used to drive the motor, turn on the air conditioner, turn on the heater, etc. during driving.

[0036] The inventor of the present application has found through research that when the vehicle is driving, the high-voltage battery recovers from a faulty state to a normal state. If the high-voltage battery is directly activated, the following problems may occur:

[0037] High-voltage attack problem: When the high-voltage battery is in a faulty state, 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. When the high-voltage electricity generated by the motor and the high-voltage electricity generated by the high-voltage battery meet each other, the high-voltage side will attack the low-voltage side, 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 burn the main relay, further affecting the safety and reliability of the vehicle.

[0039] Based on the above problems, in the prior art, in limp home mode, if the high-voltage battery recovers from a faulty state to a normal state, it is usually not allowed to directly enable the high-voltage battery. Instead, the driver is required to stop the vehicle and restart the vehicle before re-enabling the high-voltage battery. Although this approach ensures safety, it also brings the following inconveniences:

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

[0041] Poor driving experience: Frequent parking and restarting operations reduce the driving experience, especially in emergency situations or on busy traffic roads, which may affect driving efficiency and safety.

[0042] Therefore, how to safely and conveniently enable the high-voltage battery in limp mode has become a technical problem that needs to be solved urgently. Based on this, an embodiment of the present application provides a vehicle control method, which is applied to a hybrid vehicle, and can be specifically applied to a controller or control system of the vehicle. The method aims to achieve safe and convenient activation of the high-voltage battery after it recovers from an abnormal state to a normal state, so that the vehicle can recover from limp mode to normal mode.

[0043] Figure 1 It is a schematic flow chart of a vehicle control method provided in an embodiment of the present application.

[0044] For example, Figure 1 As shown, the method includes:

[0045] Step 101: During vehicle driving, if an abnormality is detected in the high-voltage battery, 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 travel, and the engine drives the motor to rotate and generate electricity;

[0046] Step 102: In the limp home mode, if it is detected that 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 voltage at the motor side drops to less than or equal to a preset voltage, the pre-charge relay of the high-voltage battery is controlled to close; wherein the preset voltage is lower than the minimum operating voltage of the high-voltage battery;

[0048] Step 104: 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, the main relay is controlled to close and the pre-charging relay is controlled to open, so that the vehicle switches from limp mode to normal mode.

[0049] exist Figure 1 In the embodiment shown, during the driving process of the vehicle, if an abnormality of the high-voltage battery is detected, the vehicle is controlled to enter the limp mode to ensure that the vehicle can continue to drive safely when the high-voltage battery fails, avoiding the vehicle from completely losing power due to power supply interruption. The engine drives the motor to rotate and generate electricity, ensuring the continuous operation of the basic functions of the vehicle. In the limp mode, if the abnormality of the high-voltage battery is detected to be eliminated, it means that there are conditions for re-enabling the high-voltage battery. At this time, the motor is controlled to stop generating electricity to provide preparation conditions for switching to the normal mode. After the motor stops generating electricity, the voltage on the motor side 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 the preset voltage, the pre-charge relay is controlled to close. After the pre-charge relay is closed, the motor side voltage will be further pulled up. As the motor side voltage increases, 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 to avoid the main relay burning problem that may occur when the main relay is directly closed due to excessive voltage difference. In addition, since the preset voltage is lower than the minimum operating 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 operating voltage of the high-voltage battery, 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, thereby 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, providing a safe condition for closing the main relay. At the same time, the driver does not need to stop the car during the entire process, reducing unnecessary parking and restarting operations, and improving driving convenience and comfort.

[0050] Moreover, after the high-voltage battery returns to normal, it will not be directly enabled to emit high voltage electricity. Instead, the main relay will be closed to allow the high-voltage battery to emit 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 method of each step in the embodiment shown is described as follows:

[0052] In step 101, the various parameters (such as voltage, current, temperature, etc.) of the high-voltage battery are monitored in real time through the battery management system (BMS) inside the vehicle. Once an abnormality (such as too low voltage, too large internal resistance, abnormal temperature increase, etc.) is detected, the vehicle is controlled to enter the limp mode. The way to control the vehicle to enter the limp mode may include: controlling the main relay to disconnect 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 maintain the basic driving ability of the vehicle, and controlling the engine to drive the motor to rotate and generate electricity to maintain the basic power needs of the vehicle (such as lighting, dashboard, etc.).

[0053] Exemplarily, the states of the motor include: power generation state, torque control state, speed control state, standby state (STANDBY), initialization state and shutdown state. The power generation state means that the motor operates as a generator, and is driven to rotate by the engine to convert mechanical energy into electrical energy. The torque control state means that the motor is controlled according to the set torque value to accurately adjust the output torque of the motor. The speed control state means that the motor is controlled according to the set speed value to accurately adjust the speed of the motor. The standby state means that the motor is in a zero-power waiting state, at which time the motor rotates but does not generate electricity and does not output torque. The initialization state refers to the self-test and initialization process before the motor starts to ensure that all parameters are set correctly and are ready for normal operation. The shutdown state means that the motor stops working completely and all power supplies are cut off. When the vehicle enters limp mode, the control system controls the motor to jump to the power generation state.

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

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

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

[0057] In one possible implementation, after controlling the vehicle to enter the limp home mode, it also includes: setting the state of the compressor of the vehicle's air-conditioning system to a power-adjustable state, and controlling the power demand of the compressor to 0; or; setting the state of the compressor of the vehicle's air-conditioning system to a disabled state; wherein, in the disabled state, the compressor is prohibited from operating.

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

[0059] After the vehicle enters limp home mode, the high-voltage battery cannot output high-voltage electricity. Although the motor can generate electricity, the vehicle's power resources become limited, and priority must be given to ensuring the power supply of key systems (such as steering, braking, etc.). The compressor of the air-conditioning system consumes a lot of power, especially in high or low temperature environments. Therefore, setting the compressor status to a power-adjustable state or a disabled state can save precious electricity for more critical driving functions.

[0060] During a high-voltage battery failure, the voltage and current generated by the motor may be unstable. As a high-power device, the compressor is sensitive to voltage fluctuations. In order to avoid damage to the compressor or other equipment due to voltage instability, limiting its power or prohibiting its operation is an effective protective measure. In addition, 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 power generation voltage. Therefore, in this embodiment, during a high-voltage battery failure, the vehicle is in limp mode, and the compressor is controlled to be in a prohibited state, or even if the compressor is controlled to be in a power adjustable state, the power demand of the compressor is also controlled to be 0 at the same time, that is, the compressor is controlled to have no power demand. Controlling the power demand 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 the limp home mode, the state of the compressor is set to the power adjustable state, and the power demand of the compressor is controlled to 0; or; the state of the compressor is set to the disabled state, which can save the electric energy generated by the motor for more critical driving functions, and avoid the compressor as a load on the motor, affecting the stable output of the motor's power generation voltage. Setting the compressor to the power adjustable state and ensuring that it has no power demand is actually an energy-saving measure achieved through flexible control logic. Even when power is limited, the compressor is still able to start at any time to cope with sudden 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 It is a schematic diagram of the architecture of another high-voltage system of 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 Converter, DC-DC), and the low voltage system 208 can be a 12V system.

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

[0066] The states of the high-voltage to low-voltage device include: step-down state, standby state, initialization state and shutdown state. The step-down state means that the high-voltage to low-voltage device steps down the power generation voltage of the motor to meet the power supply requirements of the vehicle's low-voltage system (such as 12V battery and various low-voltage electrical appliances). The standby state means that the high-voltage to low-voltage device is in a zero-power waiting state, ready to receive a start command at any time, and maintains a communication connection with the control system. The initialization state means the self-check and initialization process before the high-voltage to low-voltage device starts, ensuring that all parameters are set correctly and ready to work normally. The shutdown state means that the high-voltage to low-voltage device completely stops working, cuts off all power supply, and does not perform any operation. In limp mode, before the abnormality of the high-voltage battery is eliminated, the control system controls the vehicle's high-voltage to low-voltage device to enter the step-down state from the standby state.

[0067] In addition, the inventor of the present application discovered through research that in order to make the high-voltage to low-voltage device enter the step-down state, it is easier to suppress the increase in the motor's power generation voltage, so it is chosen to let the motor generate electricity for a while, and then control the high-voltage to low-voltage device to enter the step-down state.

[0068] In one possible implementation, in 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; the above-mentioned high-voltage to low-voltage device that controls the vehicle to enter a voltage reduction state includes: detecting the power generation voltage of the motor during power generation; if the power generation voltage is greater than a preset voltage threshold and less than a second target voltage, controlling the high-voltage to low-voltage device to start entering a voltage reduction 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 is controlled to drive the motor 206 to rotate and generate electricity, the maximum power generation voltage of the motor 206 is set to the first target voltage. Assuming that the rated voltage of the high-voltage battery 201 is 400V, the first target voltage may be greater than or equal to 400V.

[0070] It is understandable that after the motor 206 starts to generate electricity, it will take some time for its actual power generation voltage to rise to the first target voltage. During this process, the power generation voltage of the motor 206 during the power generation process is detected. If the power generation voltage is greater than the preset voltage threshold and less than the second target voltage, the high-voltage to low-voltage device 207 is controlled to enter the step-down state to step down the power generation voltage of the motor 206 to power the vehicle's low-voltage system 208. At the same time, the high-voltage to low-voltage device 207 entering the step-down state can serve as a load for the motor 206 to restrict the rapid rise of the power generation voltage of the motor 206.

[0071] Considering that the maximum power generation voltage of the motor is designed based on the rated voltage of the high-voltage battery, if the power generation voltage of the motor is too high, it may damage the electrical equipment; and if the power generation voltage is too low, it is difficult to effectively control the state of the motor in the initial power generation. Based on this, the vehicle control system requires the high-voltage to low-voltage device to enter the step-down state at the right time, with the purpose of restricting the rapid rise of the power generation voltage by using it as a load before the motor generates voltage and reaches the second target voltage, ensuring that the motor power generation voltage is maintained within a safe and controllable range to avoid excessive motor power generation voltage. In addition, the high-voltage to low-voltage device will not enter the step-down state at the initial power generation of the motor to avoid the uncontrollable state of the motor in the initial power generation. At the same time, the maximum power 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 range for the high-voltage to low-voltage device to restrict the rapid rise of the motor voltage, making it easier for the high-voltage to low-voltage device to enter the step-down state at the right time to control the power generation voltage of the motor.

[0072] For example, see Figure 4 , Figure 4 This is a schematic diagram of the relationship between the power generation voltage and time after a motor starts generating power, provided in an embodiment of the present application. Figure 4 In the example, the maximum power generation voltage of the motor is 400V, U1 is the preset voltage threshold, U2 is the second target voltage, U1 is greater than 0, and U2 is less than 400V. For example, U1 = 130V, U2 = 360V, when the power generation voltage is between U1 and U2, the high-voltage to low-voltage device is controlled to enter the step-down state, which has a better control effect on the power generation voltage of the motor. Figure 4 It can be seen that when the power generation voltage is between U1 and U2, the high-voltage to low-voltage device is allowed to intervene and enter the voltage reduction state, which is equivalent to avoiding the stage where the motor power generation voltage changes rapidly (the stage when power generation just starts, and the stage when the maximum power generation voltage is about to be reached). If the power generation voltage changes too quickly, it may cause the high-voltage to low-voltage device to enter the voltage reduction state, and it is difficult to control the rapidly rising motor power generation voltage. When the power generation voltage is between U1 and U2, the power generation voltage changes relatively slowly, so it is easier to control the power generation voltage by controlling the high-voltage to low-voltage device to enter the voltage reduction state when the power generation voltage is between U1 and U2.

[0073] In the above technical solution, in limp mode, by setting a higher first target voltage, a longer voltage range is provided for the high-voltage to low-voltage device to restrict the rapid rise of the motor's power generation voltage, so that it can enter the voltage reduction state at the right time, thereby realizing effective control of the motor's power generation voltage. Combined with dynamic monitoring of the power generation voltage, timely control of the high-voltage to low-voltage device to enter the voltage reduction state to power the low-voltage system not only avoids the risks that may be caused by excessive motor power generation voltage, but also ensures the stable power supply of the low-voltage system, effectively realizes the safe management of the motor's power generation voltage, and also improves the safety and reliability of the vehicle.

[0074] In step 102, it is considered that the abnormality of the high-voltage battery may be eliminated by itself during the driving process of the vehicle. For example, at noon in the hot summer, after the high-voltage battery overheats and reports an abnormality, 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. When the high-voltage battery cools down half an hour later, the abnormality of the high-voltage battery overheating is eliminated. Based on this, in limp mode, the BMS can continue to monitor the high-voltage battery in real time to check whether its various parameters have returned to normal. For example, a series of diagnostic standards are set (such as voltage returns to the normal range, temperature is stable, etc.), and when various 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 has been eliminated, the motor is controlled to stop generating electricity, such as controlling the motor to jump from the power generation 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 voltage on the motor side is the residual electricity left after the motor stops generating electricity. Since the high-voltage battery does not output high-voltage electricity at this time, the voltage on the motor side will gradually decrease. Figure 2 , the motor side voltage is Figure 2 The voltage between one side of the motor 206 and the second end of the main positive relay 202 is the voltage between point c and point d in the figure. During the process of the motor side voltage decreasing, the motor side voltage can be continuously detected. If it is detected that the motor side voltage drops to less than or equal to the preset voltage, the pre-charge relay is controlled to close.

[0076] Among them, the preset voltage is lower than the minimum operating voltage of the high-voltage battery. It is understandable that the high-voltage battery has a corresponding normal operating voltage range. For example, the normal operating voltage range of the high-voltage battery is 270V to 390V, and the minimum operating voltage of the high-voltage battery is 270V, so 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 operating voltage of the high-voltage battery. For example, if the limp mode is expected to switch to the normal mode quickly, 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 the limp mode is expected to switch to the normal mode slowly, the preset voltage can be set relatively low, which can extend the time required for the motor side voltage to drop below the preset voltage, thereby extending the time to switch from the limp mode to the normal mode. The setting of the preset voltage makes the time to switch from the limp mode to the normal mode controllable, and can be adjusted according to actual needs to balance the response speed and system stability.

[0077] It is understandable that the voltage difference on both sides of the pre-fill relay does not usually affect the safe closure of the pre-fill relay. In the related art, in general, even if there is a large voltage difference on both sides of the pre-fill relay, the pre-fill relay can be safely controlled to close. For example, the voltage difference on both sides of the pre-fill relay may be very large. The low-voltage side (such as the motor side) may be below 60V, while the high-voltage side (such as the high-voltage battery side) may reach several hundred volts (for example, 300V to 400V). Although the voltage difference on both sides of the pre-fill relay is large in this case, it does not affect its safe closure.

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

[0079] Among them, the first preset time length can be pre-calibrated, for example, calibrated to 1 second, in order to extend the time length that the high-voltage to low-voltage device is in the step-down state, so that even if the motor stops generating electricity, the high-voltage to low-voltage device can continue to serve as the load of the motor, consume the residual electricity after the motor stops generating electricity, and make the residual electricity voltage of the motor after it stops generating electricity drop to below the preset voltage as soon as possible. For example, if the high-voltage to low-voltage device immediately exits the step-down state and enters the standby state after the motor stops generating electricity, then the voltage on the motor side is in a natural decline process, and it may take 20 seconds for the voltage on the motor side to drop to 30V. However, if the high-voltage to low-voltage device delays the first preset time length before exiting the step-down state after the motor stops generating electricity, then the voltage on the motor side will be in a rapid decline process, and it may only take 1 second for the voltage on the motor side to drop to 30V, which accelerates the rate of decline of the voltage on the motor side. It should be noted that the above-mentioned values ​​of 30V, 20 seconds, 1 second, etc. are all examples for ease of understanding, and are not limited to this in specific implementations.

[0080] The high-voltage-to-low-voltage device is controlled to exit the voltage reduction state, that is, the high-voltage-to-low-voltage device is controlled to enter the standby state. After the high-voltage-to-low-voltage device enters the standby state, the high-voltage-to-low-voltage device has no power demand and is in a state where high-voltage electricity is not required. It will not consume the high-voltage electricity generated by the motor, nor will it consume the residual electricity after the motor stops generating electricity.

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

[0082] In the above implementation, after the motor stops generating electricity, the high-voltage to low-voltage device is controlled to delay exiting the step-down state. After the motor stops generating electricity, the voltage on the motor side begins to drop. By controlling the high-voltage to low-voltage device to exit the step-down state after the first preset time period, the high-voltage to low-voltage device can continue to serve as the load of the motor within the first preset time period to continue consuming the residual electricity remaining after the motor stops generating electricity. This helps to speed up the rate of decrease of the voltage on the motor side, so that the voltage on the motor side quickly drops to less than or equal to the preset voltage, so as to meet the conditions for closing the pre-charging relay as soon as possible. This helps to shorten the time required to close the pre-charging relay after the motor stops generating electricity, and speed up the vehicle's switching from limp mode to normal mode.

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

[0084] In another possible implementation, after the motor stops generating electricity, it also includes: controlling the high-voltage to low-voltage device to exit the step-down state, and delaying the second preset time to send a closing instruction for the pre-charging relay; correspondingly, if it is detected that the voltage on the motor side drops to less than or equal to the preset voltage, then controlling the pre-charging relay of the high-voltage battery to close, including: if it is detected that the voltage on the motor side drops to less than or equal to the preset voltage, then controlling the pre-charging relay of the high-voltage battery to close based on the closing instruction.

[0085] In this implementation, after the motor stops generating electricity, it will not delay the high-voltage to low-voltage device from exiting the step-down state, that is, it will not delay stopping the step-down function of the high-voltage to low-voltage device, but it will delay sending the closing command of the pre-charging relay, that is, after the motor stops generating electricity, it will delay sending the closing command of the pre-charging relay after a second preset time. In this case, it is equivalent to waiting for the motor side voltage to drop naturally under no-load conditions, so that during the natural drop of the motor side voltage, 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 close based on the closing command.

[0086] The second preset time length can be pre-calibrated, for example, by referring to the time length required for the motor side voltage to naturally drop to the preset voltage. The second preset time length can be greater than or equal to the time length 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 less than or equal to the preset voltage, the pre-charge relay of the high-voltage battery can be controlled to close based on the closing instruction.

[0087] In a specific implementation, the second preset duration is usually greater than the first preset duration.

[0088] In the above implementation, after the motor stops generating electricity, the high-voltage to low-voltage device is controlled to exit the step-down state without delay, and the closing instruction of the pre-charging relay is sent after a delay of the second preset time, which can ensure that the voltage on the motor side steadily drops to below the preset voltage, which not only avoids the control system from falsely reporting faults, but also improves the reliability and stability of the system. It can be understood that after the high-voltage to low-voltage device exits the step-down state, the motor is equivalent to losing the load of the high-voltage to low-voltage device, so the rate of decrease of the voltage on the motor side will become slow. It takes a certain amount of time to wait for the voltage on the motor side to drop to less than or equal to the preset voltage. By delaying the closing instruction of the pre-charging relay for the second preset time, it is beneficial to let the control system know that the waiting time is actually waiting for the closing instruction of the pre-charging relay to be sent, rather than an operation delay caused by other unknown reasons, which helps to avoid the control system from falsely reporting faults due to waiting for unknown reasons, and improves the reliability and stability of the system.

[0089] In step 104, after the pre-charging relay is closed, the pre-charging circuit is turned on, so that the voltage on the motor side begins to rise. During the process of the motor side voltage rising, 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 the preset voltage difference. 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-charging relay is controlled to disconnect to switch from limp mode to normal mode. The voltage difference between the motor side voltage and the high-voltage battery side voltage is the voltage difference between the two sides of the main relay, and the voltage difference between the two sides of the main positive relay is basically the same as the voltage difference between the two sides of the main negative relay. This embodiment is based on monitoring Figure 2 The voltage difference across the main positive relay 202 is shown as an example for explanation.

[0090] See also Figure 2 , the voltage difference between the two 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 Figure 2 The voltage between the positive electrode of the high-voltage battery 201 and the first end of the main positive relay 202 is the voltage between point a and point b in the figure. The motor side voltage is Figure 2 The voltage between one side of the motor 206 and the second end of the main positive relay 202, such as the voltage between point c and point d in the figure.

[0091] In a specific implementation, a voltage sensor can be used to measure the voltage on the high-voltage battery side and the voltage on the motor side, respectively, and the voltage difference between the voltage on the high-voltage battery side and the voltage on the motor side can be calculated by the control system, and the absolute value thereof is taken as the voltage difference in step 104. Then, it is determined whether the absolute value of the voltage difference on both sides of the relay is less than the preset voltage difference. The preset voltage difference can be a pre-calibrated safety voltage difference threshold, which is intended to measure whether the voltage difference on both sides of the main relay is close enough, so close that even if the voltage difference exists, it will not affect the safe closing of the relay. For example, if the voltage on the motor side is equal to 100% ±5% of the voltage on the high-voltage battery side, it can be determined whether the voltage difference on both sides of the main relay is less than the preset voltage difference. The ±5% can be pre-calibrated, or it can be calibrated to ±2% or ±10%, etc. This embodiment does not specifically limit this.

[0092] When 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 control system issues a main relay closing command to close the main relay and re-establish 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 re-establish 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 limp mode to normal mode, the vehicle speed may also be considered. When the vehicle speed is lower than a preset speed threshold, the vehicle is switched from limp mode to normal mode, so as to improve the safety of mode switching to a certain extent. The preset speed threshold may be pre-calibrated, for example, it may be set to 130km / h or 60km / h, but this embodiment does not specifically limit this. In normal mode, the vehicle is supplied with high voltage electricity by a high-voltage battery.

[0094] In the above implementation, after the vehicle enters the limp mode, the compressor is controlled to be in a power-adjustable state or a prohibited state with no power demand. 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 switches from the limp 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] Among them, allowing the power demand of the compressor to be greater than 0 can be understood as: the control system allows the power request value of the compressor to be greater than 0, and will apply a rotational torque to it according to the power request value of the compressor. In other words, the control system dynamically adjusts the power output of the compressor by adjusting the rotational torque of the compressor motor according to the actual power demand to meet the required cooling or heating needs. Since the state of the compressor is a power adjustable state at this time, although the compressor has a power demand, the compressor will still be controlled to operate at limited power, that is, the control system will still limit the maximum operating power of the compressor to prevent the actual operating power of the compressor from 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 limiting its power.

[0097] In the above implementation, after the vehicle returns to normal mode, the high-voltage battery can work normally, so the state of the compressor is set to an adjustable power 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, which is conducive to timely restoration of the operation of the compressor to realize functions related to the compressor such as turning on the air conditioner and turning on the heater.

[0098] In some implementations, after step 104, it also 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 switched to 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.

[0099] Among them, the current gear of the vehicle is the driving gear, which means that the vehicle is currently in the driving process. The remaining power of the high-voltage battery is greater than the preset power threshold, which means that the current remaining power of the high-voltage battery is sufficient to meet the power supply demand of the high-voltage system. At this time, the target flag is activated. Each subsystem in the vehicle can monitor the message of the activation of the target flag to make it clear that the high-voltage battery is currently allowed to power high-voltage electrical equipment and the motor is allowed to participate in the driving of the vehicle. When the target flag is activated, the control system allows the high-voltage battery to power high-voltage electrical equipment (such as air-conditioning compressors, heaters, high-voltage to low-voltage devices, etc.) and allows the motor to participate in the driving of the vehicle. This means that the vehicle can make full use of the energy of the high-voltage battery and restore normal working performance. The driver can immediately feel the full function of the vehicle restored to normal mode without worrying about any potential functional limitations or delays. The above preset power threshold can be pre-calibrated to measure whether the remaining power of the high-voltage battery pack is sufficient.

[0100] It is understandable that although the vehicle has been restored from limp mode to normal mode, the various controllers (such as motor controller, vehicle controller, etc.) / subsystems (such as power management system, air conditioning system, etc.) in the vehicle may not have received notification of this change. If no action is taken, these controllers may mistakenly believe that the high-voltage battery has not yet returned to normal or that the motor cannot drive the vehicle normally, resulting in unnecessary restrictions or erroneous operations. By activating the target flag, the control system can clearly send a signal to each controller / subsystem of the vehicle to inform them that the high-voltage battery has restored normal power supply capacity and the motor has normal driving function. This helps to ensure that each controller / subsystem can update its working status in a timely manner to avoid misjudgment or delayed response due to information asynchrony. In particular, it helps the motor controller know that the motor can currently drive the vehicle, so that the motor controller can normally control the motor to output the driving torque based on the received driving torque request.

[0101] The introduction of the target flag enhances the coordination between vehicle controllers. As a global status identifier, the target flag enables each subsystem to reach a consistent understanding at the same time, ensuring that all controllers can obtain the latest status information in a timely manner, avoiding operational errors or resource waste caused by 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 status information, improving the vehicle's ability to cope with emergencies.

[0102] Figure 5 FIG. 2 is a schematic diagram showing the principle of activating the target flag bit in this embodiment. Figure 5 As shown, 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 power of the high-voltage battery is greater than the preset power threshold, the main positive relay is closed, the main negative relay is closed, and the high-voltage battery has no faults, then the target flag can be activated. The activation of the target flag also means that the high-voltage battery has been switched to power the vehicle. After the target flag is activated, the control system can achieve a step-by-step torque increase for the torque demand of the motor so that the motor can participate in the driving of the vehicle. At the same time, the high-voltage battery can simultaneously power the high-voltage to low-voltage device, compressor and other high-voltage electrical equipment.

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

[0104] In some implementations, when the abnormality of the high-voltage battery is eliminated, if the vehicle is not detected to be switched from the limp home mode to the normal mode within a third preset time period, 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 limp mode to normal mode. However, due to the possibility of other unforeseen problems (such as leakage, poor grounding, loose connection, etc.), the vehicle failed to complete this switch within the expected time. Based on this, a reasonable third preset time is defined in this embodiment. The third preset time is based on the maximum time required for the vehicle to switch from limp mode to 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 can be set to 45 seconds to leave a certain buffer time. If the control system fails to detect that the vehicle has successfully switched from limp mode to normal mode within the above third preset time, the system will automatically switch the vehicle back to limp mode. Through this mechanism, it is ensured that even if the high-voltage battery returns to normal, but cannot be smoothly switched to normal mode due to other reasons, the vehicle is still in a relatively safe state to avoid potential risks.

[0106] In summary, in this embodiment, when the hybrid vehicle is in limp mode, after the high-voltage battery recovers from abnormality, it automatically switches to the normal high-voltage battery supply state during driving, which ensures the safety of the vehicle without affecting 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 It is a structural schematic diagram of a vehicle control device provided in an embodiment of the present application.

[0108] For example, Figure 6 As shown, the vehicle control device 600 includes:

[0109] The limp home control module 601 is used to control the vehicle to enter a limp home mode if an abnormality is detected in the high-voltage battery during vehicle driving; 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;

[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 used to control the pre-charging relay of the high-voltage battery to close if it is detected that the voltage at the motor side drops to less than or equal to a preset voltage after the motor stops generating electricity; wherein the preset voltage is lower than the minimum operating voltage of the high-voltage battery;

[0112] The mode switching control module 604 is used to control the main relay to close and the pre-charging relay to disconnect 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 a preset voltage difference, so as to switch the vehicle from the limp mode to the normal mode.

[0113] In one possible implementation, the vehicle control device also includes: a high-voltage to low-voltage device module, which is used to control the high-voltage to low-voltage device of the vehicle to enter a voltage reduction state before the abnormality of the high-voltage battery is eliminated; in the voltage reduction state, the high-voltage to low-voltage device is controlled to reduce the power generation voltage of the motor to power the low-voltage system of the vehicle.

[0114] In one possible implementation, in the limp 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; the high-voltage to low-voltage device module is specifically used to: detect the power generation voltage of the motor during the power generation process; if the power generation voltage 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 a voltage reduction state; wherein the second target voltage is less than or equal to the first target voltage.

[0115] In one possible implementation, the high-voltage to low-voltage device module is also used to: after the motor stops generating electricity, start timing from the moment the motor stops generating electricity to obtain a timing duration; after the timing duration reaches a first preset duration, control the high-voltage to low-voltage device to exit the voltage reduction state.

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

[0117] In one possible implementation, the vehicle control device also includes: a compressor control module, which is used after controlling the vehicle to enter the limp home mode. The method also includes: setting the state of the compressor of the vehicle's air-conditioning system to a power-adjustable state, and controlling the power demand of the compressor to 0; or; setting the state of the compressor of the vehicle's air-conditioning system to a disabled state; wherein, in the disabled state, the compressor is prohibited from operating.

[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 a 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 also used for, when the abnormality of the high-voltage battery is eliminated, the method further includes: if the vehicle is not detected to switch from the limp mode to the normal mode within a third preset time period, switching the vehicle back to the limp mode.

[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 an executable program code, and the processor is used to call and execute the executable program code to execute a vehicle control method provided by an embodiment of the present application.

[0124] In this embodiment, the functional modules of the device can be divided according to the above method example. For example, each functional module can be corresponded, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0125] In the case of dividing each functional module according to each function, the device may also include a first control module, a first detection module, a second detection module, a second control 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, which will not be repeated here.

[0126] It should be understood that the device 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.

[0127] In the case of an integrated unit, the device may include a processing module and a storage module. When the device is applied to a vehicle, the processing module may be used to control and manage the actions of the vehicle. The storage module may be used to support the vehicle in executing related program codes, etc.

[0128] The processing module may be a processor or a controller, which may implement or execute various exemplary logic blocks, modules and circuits shown in conjunction with the disclosure of the present application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module may be a memory.

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

[0130] This embodiment also provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is run on a computer, the computer executes the above-mentioned related method steps to implement a vehicle control method provided by the above embodiment.

[0131] This embodiment also provides a computer program product. When the computer program product is run on a computer, the computer is caused to execute the above-mentioned related steps to implement a vehicle control method provided by the above-mentioned embodiment.

[0132] Among them, the device, computer-readable storage medium, computer program product or chip provided in this embodiment is used to execute the corresponding method provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method provided above, and will not be repeated here.

[0133] 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 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.

[0134] In the embodiments provided in the present 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 only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, 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.

[0135] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A vehicle control method, characterized in that: The method comprises: During the 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, 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, the motor is controlled to stop generating electricity; After the motor stops generating electricity, if it is detected that the voltage on the motor side drops to less than or equal to a preset voltage, the pre-charge relay of the high-voltage battery is controlled to close; wherein the preset voltage is lower than the minimum operating 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, the main relay is controlled to close and the pre-charging relay is controlled to open, so that the vehicle switches from the limp mode to the normal mode.

2. The method according to claim 1, characterized in that Before the abnormality of the high-voltage battery is eliminated, the method further includes: Controlling the high-pressure to low-pressure device of the vehicle to enter a pressure 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.

3. The method according to claim 2, characterized in that 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; The controlling the high-pressure to low-pressure device of the vehicle to enter a pressure reduction state comprises: Detecting the power generation voltage of the motor during power generation; If the generated voltage 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 a voltage reduction state; wherein the second target voltage is less than or equal to the first target voltage.

4. The method according to claim 2, characterized in that: After the motor stops generating electricity, the method further includes: Starting timing from the moment when the motor stops generating electricity, obtaining the timing duration; After the timing duration reaches a first preset duration, the high-pressure to low-pressure conversion device is controlled to exit the pressure reduction state.

5. The method according to claim 2, characterized in that: After the motor stops generating electricity, the method further includes: Controlling the high-voltage to low-voltage device to exit the voltage reduction state, and delaying the second preset time to send a closing instruction for the pre-charging relay; If it is detected that the voltage at the motor side drops to less than or equal to a preset voltage, controlling the pre-charge relay of the high-voltage battery to close includes: 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.

6. The method according to claim 1, characterized in that After controlling the vehicle to enter the limp home mode, the method further includes: 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 0; or; The state of the compressor of the air conditioning system of the vehicle is set to a disabled state; wherein, in the disabled state, the compressor is disabled from operating.

7. The method according to claim 6, characterized in that After the vehicle is switched from the limp home mode to a normal mode, the method further includes: 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; The state of the compressor is set to a normal state; wherein, in the normal state, the compressor is allowed to operate normally.

8. The method according to claim 1, characterized in that After controlling the main relay to close and controlling the pre-charging relay to open so that the vehicle switches from the limp home mode to a 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, then activating a target flag; 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.

9. The method according to claim 1, characterized in that: In the 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 period, the vehicle is switched back to the limp home mode.

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

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