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

Abstract

The application discloses a vehicle control method, a vehicle and a computer readable storage medium. The method comprises the following steps: obtaining vehicle state information, wherein the vehicle state information is used to represent a real-time running state of the vehicle; determining a driving motor fault level based on the vehicle state information and a preset temperature threshold, wherein the driving motor fault level is used to determine the over-temperature degree of the driving motor; determining a vehicle control operation according to the driving motor fault level; and performing over-temperature protection on the driving motor based on the vehicle control operation. The application solves the technical problem that the system has high safety risk and poor performance when the related hybrid vehicle performs over-temperature protection on the driving motor.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and more specifically, to a vehicle control method, a vehicle, and a computer-readable storage medium. Background Technology

[0002] With the increasing popularity of hybrid vehicles, drive motors are prone to performance degradation or even damage due to overheating under high load conditions. Related technologies generally employ motor power or torque derating strategies based on temperature thresholds, achieving passive protection through power limiting and heat reduction. While some solutions optimize the smoothness of power changes, they remain limited to the local control of a single electric drive unit. Moreover, these methods cannot distinguish the causes of overheating; similar derating strategies are applied to situations such as short-term high loads or cooling system failures, lacking scenario adaptability. Furthermore, these technologies fail to identify the critical fault chain caused by cooling system failure, which leads to engine reverse-driving of the drive motor, generating high back electromotive force, requiring a large weak magnetic current from the inverter, and ultimately causing secondary overheating and burnout of the inverter, posing a serious safety hazard.

[0003] There is currently no effective solution to the above problems. Summary of the Invention

[0004] This application provides a vehicle control method, a vehicle, and a computer-readable storage medium to at least solve the technical problems of high system safety risk and poor performance when the drive motor over-temperature protection is performed in related hybrid vehicles.

[0005] According to one aspect of the embodiments of this application, a vehicle control method is provided, comprising: acquiring vehicle status information, wherein the vehicle status information is used to represent the real-time operating status of the vehicle; determining a drive motor fault level based on the vehicle status information and a preset temperature threshold, wherein the drive motor fault level is used to determine the degree of overheating of the drive motor; determining a vehicle control operation based on the drive motor fault level; and performing overheat protection on the drive motor based on the vehicle control operation.

[0006] Optionally, the vehicle status information includes: drive motor temperature and inverter temperature. Based on the vehicle status information and preset temperature thresholds, determining the drive motor fault level includes: in response to the drive motor temperature being less than or equal to a first temperature threshold, or the inverter temperature being less than or equal to a second temperature threshold, determining the drive motor fault level as a slight overheating level, wherein the first temperature threshold is greater than the second temperature threshold; or, in response to the drive motor temperature being greater than or equal to a third temperature threshold, or the inverter temperature being greater than or equal to a fourth temperature threshold, determining the drive motor fault level as a slight overheating level, wherein the third temperature threshold is greater than the first temperature threshold and the fourth temperature threshold is greater than the third temperature threshold; or, in response to the drive motor temperature being greater than or equal to a fifth temperature threshold, or the inverter temperature being greater than or equal to a sixth temperature threshold, determining the drive motor fault level as a moderate overheating level, wherein the fifth temperature threshold is greater than the sixth temperature threshold and the sixth temperature threshold is greater than the fourth temperature threshold; or, in response to the drive motor temperature being greater than or equal to a seventh temperature threshold, or the inverter temperature being greater than or equal to an eighth temperature threshold, determining the drive motor fault level as a severe overheating level, wherein the seventh temperature threshold is greater than the eighth temperature threshold and the eighth temperature threshold is greater than the fifth temperature threshold.

[0007] Optionally, the vehicle status information also includes: motor water pump duty cycle, cooling fan duty cycle, drive motor output torque, drive motor rated torque, drive motor safe torque, and vehicle drive mode. The vehicle drive mode includes: engine-assisted drive mode. Based on the drive motor fault level, the vehicle control operation is determined as follows: in response to the drive motor fault level being a slight over-temperature level, controlling the motor water pump duty cycle and cooling fan duty cycle to a preset duty cycle, the drive motor output torque being less than or equal to a first torque threshold, and controlling the vehicle drive mode to engine-assisted drive mode. The first torque threshold is determined based on the drive motor rated torque, a first temperature coefficient, and the drive motor safe torque. The first temperature coefficient is determined based on the drive motor temperature. The engine-assisted drive mode is used to indicate that the engine provides driving force compensation.

[0008] Optionally, the vehicle drive mode further includes: an engine-primed drive mode, wherein the vehicle control operation is determined based on the drive motor fault level, including: in response to the drive motor fault level being a slight overheating level, controlling the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque being less than or equal to a second torque threshold, and controlling the vehicle drive mode to be an engine-primed drive mode, wherein the second torque threshold is determined based on the drive motor rated torque, a second temperature coefficient, and the drive motor safe torque, the second temperature coefficient being less than a first temperature coefficient, and the engine-primed drive mode is used to indicate that the engine provides the main driving force.

[0009] Optionally, the vehicle drive mode further includes: an engine drive mode, wherein the vehicle control operation is determined based on the drive motor fault level, including: in response to the drive motor fault level being a moderate overheat level, controlling the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, and controlling the vehicle drive mode to be an engine drive mode, wherein the engine drive mode is used to indicate that the engine provides all the driving force to the vehicle.

[0010] Optionally, the vehicle drive mode also includes an engine drive mode, and the vehicle status information also includes the power battery voltage. Based on the drive motor fault level, the vehicle control operation is determined to include: in response to the drive motor fault level being a severe overheating level, controlling the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, the vehicle drive mode to engine drive mode, and controlling the target vehicle speed to be less than a preset speed threshold, wherein the target vehicle speed is determined based on the power battery voltage and a preset mapping table, and the preset mapping table is used to represent the mapping relationship between the power battery voltage and the preset speed threshold.

[0011] Optionally, the vehicle status information also includes: communication status. The vehicle control method further includes: in response to a communication failure, controlling the duty cycle of the motor water pump to a preset duty cycle, the duty cycle of the cooling fan to a preset duty cycle, the output torque of the drive motor to a preset output torque, the vehicle driving mode to engine driving mode, the target vehicle speed to be less than a preset speed threshold, and generating a prompt message and sending the prompt message to the graphical user interface.

[0012] According to another aspect of the embodiments of this application, a vehicle control device is also provided, comprising: an acquisition module for acquiring vehicle status information, wherein the vehicle status information is used to represent the real-time operating status of the vehicle; a first determination module for determining a drive motor fault level based on the vehicle status information and a preset temperature threshold, wherein the drive motor fault level is used to determine the degree of overheating of the drive motor; a second determination module for determining a vehicle control operation based on the drive motor fault level; and a protection module for performing overheat protection on the drive motor based on the vehicle control operation.

[0013] Optionally, the vehicle status information includes: drive motor temperature and inverter temperature. The first determining module is further configured to: determine the drive motor fault level as a slight overheating level in response to the drive motor temperature being less than or equal to a first temperature threshold, or the inverter temperature being less than or equal to a second temperature threshold, wherein the first temperature threshold is greater than the second temperature threshold; or, determine the drive motor fault level as a slight overheating level in response to the drive motor temperature being greater than or equal to a third temperature threshold, or the inverter temperature being greater than or equal to a fourth temperature threshold, wherein the third temperature threshold is greater than the first temperature threshold and the fourth temperature threshold is greater than the third temperature threshold; or, determine the drive motor fault level as a moderate overheating level in response to the drive motor temperature being greater than or equal to a fifth temperature threshold, or the inverter temperature being greater than or equal to a sixth temperature threshold, wherein the fifth temperature threshold is greater than the sixth temperature threshold and the sixth temperature threshold is greater than the fourth temperature threshold; or, determine the drive motor fault level as a severe overheating level in response to the drive motor temperature being greater than or equal to a seventh temperature threshold, or the inverter temperature being greater than or equal to an eighth temperature threshold, wherein the seventh temperature threshold is greater than the eighth temperature threshold and the eighth temperature threshold is greater than the fifth temperature threshold.

[0014] Optionally, the vehicle status information also includes: motor water pump duty cycle, cooling fan duty cycle, drive motor output torque, drive motor rated torque, drive motor safe torque, and vehicle drive mode. The vehicle drive mode includes: engine-assisted drive mode. The second determining module is further configured to: in response to the drive motor fault level being a slight over-temperature level, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, and the drive motor output torque being less than or equal to a first torque threshold, and control the vehicle drive mode to engine-assisted drive mode. The first torque threshold is determined based on the drive motor rated torque, a first temperature coefficient, and the drive motor safe torque. The first temperature coefficient is determined based on the drive motor temperature. The engine-assisted drive mode is used to indicate that the engine provides driving force compensation.

[0015] Optionally, the vehicle drive mode further includes: an engine main drive mode. The second determining module is also used to: control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, and the drive motor output torque to be less than or equal to a second torque threshold, in response to the drive motor fault level being a slight overtemperature level, and to control the vehicle drive mode to the engine main drive mode. The second torque threshold is determined based on the drive motor rated torque, a second temperature coefficient, and the drive motor safe torque. The second temperature coefficient is less than the first temperature coefficient. The engine main drive mode is used to indicate that the engine provides the main driving force.

[0016] Optionally, the vehicle drive mode further includes: an engine drive mode. The second determining module is also configured to: in response to the drive motor fault level being a moderate overheat level, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, and control the vehicle drive mode to an engine drive mode, wherein the engine drive mode is used to indicate that the engine provides all the driving force to the vehicle.

[0017] Optionally, the vehicle driving mode further includes an engine driving mode, and the vehicle status information further includes the power battery voltage. The second determining module is also used to: in response to the drive motor fault level being a severe overheating level, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, the vehicle driving mode to an engine driving mode, and control the target vehicle speed to be less than a preset speed threshold, wherein the target vehicle speed is determined based on the power battery voltage and a preset mapping table, and the preset mapping table is used to represent the mapping relationship between the power battery voltage and the preset speed threshold.

[0018] Optionally, the vehicle status information also includes: communication status. The vehicle control device further includes: a third determining module, used to: in response to a communication failure, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, the vehicle drive mode to engine drive mode, the target vehicle speed to be less than a preset speed threshold, and generate a prompt message and send the prompt message to the graphical user interface.

[0019] According to another aspect of the embodiments of this application, a vehicle is also provided, including: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to execute instructions to implement the vehicle control methods in various embodiments of this application.

[0020] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored executable program, wherein, when the executable program is running, it controls the device where the computer-readable storage medium is located to execute the vehicle control method of various embodiments of this application.

[0021] According to another aspect of the embodiments of this application, a computer program product is also provided, including computer instructions that, when executed by a processor, implement the methods in various embodiments of this application.

[0022] In this embodiment, a graded fault response method based on vehicle coordination is adopted. By acquiring vehicle status information, which represents the real-time operating status of the vehicle, and then determining the drive motor fault level based on the vehicle status information and a preset temperature threshold, the drive motor fault level is used to determine the degree of overheating of the drive motor. Based on the drive motor fault level, the vehicle control operation is determined, and finally, based on the vehicle control operation, overheat protection of the drive motor is performed. This achieves the purpose of accurately identifying fault scenarios and implementing differentiated protection, thereby improving the technical effect of improving system safety and vehicle performance. It also solves the technical problem of high system safety risk and poor performance when performing drive motor overheat protection in related hybrid vehicles. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0024] Figure 1 This is a schematic diagram of a hybrid power system based on related technologies;

[0025] Figure 2 This is a flowchart of an optional vehicle control method according to an embodiment of this application;

[0026] Figure 3 This is a schematic diagram of an optional vehicle control method according to an embodiment of this application;

[0027] Figure 4 This is a schematic diagram of another optional vehicle control method according to an embodiment of this application;

[0028] Figure 5 This is a structural block diagram of an optional vehicle control device according to an embodiment of this application. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0031] With the widespread application of hybrid electric vehicles, the drive motor, as a core power component, is prone to overheating under high-intensity operating conditions due to sudden load changes or cooling system malfunctions. Related wiring control strategies generally only target the temperature of the drive motor itself, achieving passive protection through simple power reduction or torque limiting, failing to coordinate power source synergy and thermal management at the vehicle system level. Especially in extreme conditions such as cooling system failure, if the engine continues to drive the drive motor, it will force the motor into a weak magnetic field operation state, generating a large current that impacts the inverter, causing the temperature to rise continuously until it burns out, resulting in a chain reaction of "protection failure - system collapse." Furthermore, traditional solutions do not differentiate between minor overheating and severe failure, leading to a sudden drop in power output during normal driving, severely impacting the driving experience. Therefore, related technologies still suffer from high system safety risks and poor performance.

[0032] Figure 1 This is a schematic diagram of a hybrid power system based on related technologies, such as... Figure 1As shown, the system mainly consists of an engine, generator, motor, battery, clutch, and reduction gear. The engine is mechanically connected to the generator via gear pairs, enabling the generator to convert its mechanical energy into electrical energy while the engine is running. This electrical energy is used to charge the battery or directly power the motor. When the clutch is disengaged, the engine does not directly drive the vehicle; energy conversion is achieved solely through the generator. When the clutch is engaged, the engine torque is transmitted to the wheels through the clutch and reduction gear, achieving parallel drive mode with the motor. The engine, generator, and motor drive the wheels through a transmission mechanism to achieve various operating modes. The battery, as the core of energy storage and release, is monitored and managed by a Battery Management System (BMS). The motor and generator are precisely controlled in terms of torque and speed by their respective motor controllers, namely Motor Control Unit 1 (MCU1, i.e., the drive motor controller) and Motor Control Unit 2 (MCU2, i.e., the generator controller). The engine is regulated by the Engine Management System (EMS). In addition, each controller communicates in real time with the hybrid power management system (HCU) via the Controller Area Network (CAN) bus. The HCU, as the central control unit of the vehicle, comprehensively collects the status and fault information of each component, coordinates the switching of power sources, energy distribution, cooling control and fault limp strategy, so as to realize the safe, efficient and reliable operation of the hybrid power system under normal and fault conditions.

[0033] According to an embodiment of this application, a method embodiment for vehicle control is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0034] Figure 2 This is a flowchart of an optional vehicle control method according to an embodiment of this application, such as... Figure 2 As shown, the method includes the following steps:

[0035] Step S202: Obtain vehicle status information, wherein the vehicle status information is used to represent the real-time operating status of the vehicle;

[0036] Step S204: Based on vehicle status information and preset temperature threshold, determine the drive motor fault level, wherein the drive motor fault level is used to determine the degree of overheating of the drive motor.

[0037] Step S206: Determine the vehicle control operation based on the fault level of the drive motor;

[0038] Step S208: Based on vehicle control operations, over-temperature protection is performed on the drive motor.

[0039] The vehicle status information mentioned above represents multi-dimensional data reflecting the current operating status of the vehicle, collected and transmitted in real time by onboard sensors and controllers. This data includes: drive motor body temperature, drive motor inverter temperature, motor coolant temperature, power battery voltage, engine operating status, vehicle speed signal, operating parameters of the cooling system water pump and fan, vehicle speed, and controller communication status. This vehicle status information comprehensively characterizes the vehicle's thermal load and energy distribution during operation, providing accurate input for fault diagnosis.

[0040] The aforementioned preset temperature thresholds represent multiple temperature boundary points set during the system design phase based on the heat resistance characteristics of the drive motor material and the safe operating boundary of the inverter. These thresholds are used to classify over-temperature states of varying severity. This threshold system includes multiple temperature limits, such as a first temperature threshold, a second temperature threshold, a third temperature threshold, a fourth temperature threshold, a fifth temperature threshold, a sixth temperature threshold, a seventh temperature threshold, and an eighth temperature threshold. Each threshold corresponds to a specific fault level trigger condition, used to quantify the severity of thermal anomalies in the drive motor and achieve gradient identification from normal to dangerous states.

[0041] The above drive motor fault levels represent a multi-level classification based on the comparison results between vehicle status information and preset temperature thresholds. This classification is used to quantify the severity of the current thermal state of the drive motor and corresponds to: normal, slightly overheated, mildly overheated, moderately overheated, and severely overheated. Each level corresponds to different system risks and handling priorities.

[0042] The aforementioned vehicle control operations refer to system-level control commands executed by the HCU based on the fault level of the drive motor. These commands include: increasing the duty cycle of the coolant pump and cooling fan, limiting the upper limit of the drive motor's output torque, cutting off the drive motor's torque output, switching to engine-only drive mode, and dynamically setting the maximum limp speed limit based on the power battery voltage.

[0043] When the drive motor is over-temperature protected, the temperature of the drive motor body and the inverter stops rising and gradually drops by performing the corresponding vehicle control operation mentioned above. This prevents insulation aging, magnet demagnetization, or overcurrent burnout of the Insulated Gate Bipolar Transistor (IGBT) module caused by continuous high temperature, thereby ensuring the structural integrity and electrical safety of the drive motor body.

[0044] Based on the above steps S202 to S208, this embodiment of the application obtains vehicle status information, which represents the real-time operating status of the vehicle. Then, based on the vehicle status information and a preset temperature threshold, it determines the drive motor fault level, which is used to determine the degree of overheating of the drive motor. Based on the drive motor fault level, it determines the vehicle control operation. Finally, based on the vehicle control operation, it performs overheat protection on the drive motor. This achieves the purpose of accurately identifying fault scenarios and implementing differentiated protection, thereby improving the technical effect of improving system safety and vehicle performance. It also solves the technical problem of high system safety risk and poor performance when performing drive motor overheat protection in related hybrid vehicles.

[0045] Optionally, the vehicle status information includes: drive motor temperature and inverter temperature. Based on the vehicle status information and preset temperature thresholds, determining the drive motor fault level includes: in response to the drive motor temperature being less than or equal to a first temperature threshold, or the inverter temperature being less than or equal to a second temperature threshold, determining the drive motor fault level as a slight overheating level, wherein the first temperature threshold is greater than the second temperature threshold; or, in response to the drive motor temperature being greater than or equal to a third temperature threshold, or the inverter temperature being greater than or equal to a fourth temperature threshold, determining the drive motor fault level as a slight overheating level, wherein the third temperature threshold is greater than the first temperature threshold and the fourth temperature threshold is greater than the third temperature threshold; or, in response to the drive motor temperature being greater than or equal to a fifth temperature threshold, or the inverter temperature being greater than or equal to a sixth temperature threshold, determining the drive motor fault level as a moderate overheating level, wherein the fifth temperature threshold is greater than the sixth temperature threshold and the sixth temperature threshold is greater than the fourth temperature threshold; or, in response to the drive motor temperature being greater than or equal to a seventh temperature threshold, or the inverter temperature being greater than or equal to an eighth temperature threshold, determining the drive motor fault level as a severe overheating level, wherein the seventh temperature threshold is greater than the eighth temperature threshold and the eighth temperature threshold is greater than the fifth temperature threshold.

[0046] The aforementioned drive motor temperature represents the real-time operating temperature of core components such as the windings, magnets, and stator and rotor structures inside the drive motor body in hybrid vehicles. The drive motor temperature is directly collected by a temperature sensor arranged inside the drive motor and is used to characterize the heat energy level accumulated by the motor due to electrical losses, iron losses, and mechanical friction. It can be used to assess whether there are problems such as aging of motor insulation materials, risk of demagnetization of permanent magnets, and thermal deformation of mechanical structures.

[0047] The inverter temperature mentioned above represents the junction temperature or case temperature of the power semiconductor device in the drive motor controller, namely the insulated gate bipolar transistor (IGBT) module. This temperature is measured in real time by a temperature sensing element embedded near the inverter power unit. It is used to characterize the degree of local heat accumulation caused by switching losses and conduction losses during the power conversion process, and can assess whether the power electronic components are at the thermal failure critical point.

[0048] Table 1 below illustrates the fault level classification strategy of this application embodiment, as shown in Table 1:

[0049] Table 1

[0050]

[0051] As shown in the table above, the specific fault level judgment conditions and thresholds are set as follows: First, when the temperature of the drive motor body does not exceed the first temperature threshold, or the inverter temperature does not exceed the second temperature threshold, the system determines that the current thermal state is in a slightly abnormal range, i.e., it belongs to the drive motor slightly over-temperature level. At this time, the torque capability of the drive motor is limited. The first temperature threshold can be 120℃, and the second temperature threshold can be 110℃, and the first temperature threshold must be greater than the second temperature threshold. In the drive motor slightly over-temperature level, the system's tolerance for the motor body is higher than its tolerance for the inverter, reflecting a more stringent protection tendency for power devices.

[0052] Second, when the temperature of the drive motor body reaches or exceeds the third temperature threshold, or the inverter temperature reaches or exceeds the fourth temperature threshold, the system determines that the thermal state has entered a slightly deteriorated stage, which is the slightly overheating level of the drive motor. At this time, the torque capability of the drive motor is limited. The third temperature threshold can be 135℃, and the fourth temperature threshold can be 150℃, provided that the third temperature threshold is higher than the first temperature threshold, and the fourth temperature threshold is higher than the third temperature threshold. The triggering conditions for the slightly overheating level of the drive motor are more stringent than those for minor overheating, and the inverter temperature threshold is set higher than that of the motor body, reflecting a higher sensitivity to inverter heat accumulation.

[0053] Third, when the temperature of the drive motor exceeds the fifth temperature threshold, or the inverter temperature exceeds the sixth temperature threshold, the system determines that the thermal risk has threatened the system's continuous operation capability, which falls under the intermediate overheating level of the drive motor. At this point, the torque capability of the drive motor is zero. The fifth temperature threshold can be 155℃, and the sixth temperature threshold can be 154℃, satisfying the following conditions: the fifth temperature threshold is higher than the third temperature threshold, the sixth temperature threshold is higher than the fourth temperature threshold, and the fifth temperature threshold is greater than the sixth temperature threshold. In the intermediate overheating level of the drive motor, the system's tolerance for the motor body temperature is still higher than that for the inverter temperature, but the inverter temperature threshold setting is close to its safety limit, reflecting the system's priority in suppressing the risk of failure of critical electronic components.

[0054] Fourth, when the temperature of the drive motor exceeds the seventh temperature threshold, or the inverter temperature exceeds the eighth temperature threshold, the system determines that it has entered an extreme thermal runaway risk state, which is the severe overheating level of the drive motor. At this time, the torque capability of the drive motor is zero, and the drive motor speed is limited. The seventh temperature threshold can be 160℃, and the eighth temperature threshold can be 157℃, satisfying the following conditions: the seventh temperature threshold is higher than the fifth temperature threshold, the seventh temperature threshold is greater than the eighth temperature threshold, and the eighth temperature threshold is greater than the fifth temperature threshold. In the severe overheating level of the drive motor, the inverter temperature threshold setting exceeds the intermediate overheating threshold of the motor body, forming a "penetrating" protection for the inverter, preventing it from being damaged due to localized overheating before the motor body reaches its limit.

[0055] In one optional embodiment, the system determines that the drive motor temperature is in a normal state when the drive motor temperature is less than or equal to a ninth temperature threshold, or the motor cooling water temperature is less than or equal to a ninth temperature threshold, or the inverter temperature is less than or equal to a tenth temperature threshold. The ninth temperature threshold can be 100°C, and the tenth temperature threshold can be 55°C. The ninth temperature threshold is the upper limit of normal operating temperature for the drive motor body, and the tenth temperature threshold is the upper limit of normal operating temperature for the inverter, satisfying the condition that the ninth temperature threshold is greater than the tenth temperature threshold. The aforementioned motor cooling water temperature represents the real-time temperature value measured at the outlet or key monitoring point of the coolant flowing through the drive motor cooling circuit. This temperature is collected by a temperature sensor installed in the cooling pipeline and transmitted to the HCU via the controller local area network. The motor cooling water temperature characterizes the efficiency of the cooling medium in effectively removing heat from the drive motor body and can directly evaluate the heat exchange performance of the cooling system.

[0056] Based on the above optional embodiments, the embodiments of this application realize independent, hierarchical, and asymmetric joint diagnosis of the thermal state of the drive motor body and the inverter. By constructing multiple sets of threshold boundaries with strict hierarchical relationships and temperature gradients, the fault level determination can accurately correspond to the over-temperature state of different components and different risk levels, which significantly improves the accuracy of over-temperature identification and the protection priority of key electronic devices. Thus, a highly robust fault classification mechanism based on dual temperature source collaborative judgment is established without relying on external information.

[0057] Optionally, the vehicle status information also includes: motor water pump duty cycle, cooling fan duty cycle, drive motor output torque, drive motor rated torque, drive motor safe torque, and vehicle drive mode. The vehicle drive mode includes: engine-assisted drive mode. Based on the drive motor fault level, the vehicle control operation is determined as follows: in response to the drive motor fault level being a slight over-temperature level, controlling the motor water pump duty cycle and cooling fan duty cycle to a preset duty cycle, the drive motor output torque being less than or equal to a first torque threshold, and controlling the vehicle drive mode to engine-assisted drive mode. The first torque threshold is determined based on the drive motor rated torque, a first temperature coefficient, and the drive motor safe torque. The first temperature coefficient is determined based on the drive motor temperature. The engine-assisted drive mode is used to indicate that the engine provides driving force compensation.

[0058] The above-mentioned motor water pump duty cycle represents the proportion of the electronic control working cycle of the water pump in the drive motor cooling system to the total control cycle. The motor water pump duty cycle is adjusted by the HCU through pulse width modulation signal to control the size of the coolant circulation flow rate. The higher the duty cycle, the faster the coolant flow rate and the stronger the heat dissipation capacity.

[0059] The aforementioned cooling fan duty cycle represents the proportion of the electronic control working cycle of the cooling fan in the drive motor cooling system to the total control cycle. The cooling fan duty cycle is adjusted by the HCU through a pulse width modulation signal to control the amount of airflow through the radiator. The higher the duty cycle, the higher the heat exchange efficiency of the radiator surface and the stronger the cooling capacity.

[0060] The aforementioned drive motor output torque represents the actual mechanical torque value that the drive motor currently outputs to the vehicle's transmission system. The drive motor output torque value is calculated and fed back in real time by the drive motor controller based on the vehicle's power requirements and thermal management strategy, and is used to directly measure the motor's output capability.

[0061] The rated torque of the drive motor mentioned above represents the maximum safe torque value that the drive motor can continuously output under rated operating conditions. The rated torque of the drive motor is determined by the motor design specifications and is a benchmark reference value for judging the upper limit of the motor's output capacity. It does not change with the operating temperature.

[0062] The aforementioned safe torque for the drive motor represents the upper limit of the torque that can be safely output under the current drive motor temperature conditions, calculated and fed back in real time by the drive motor controller based on a thermal model. The safe torque value of the drive motor dynamically decreases as the motor body temperature increases, in order to prevent material performance degradation or insulation failure due to overheating.

[0063] The aforementioned vehicle drive modes represent the operating states of the power source combination in a hybrid system, including but not limited to: pure electric drive mode, engine direct drive mode, engine-assisted drive mode, and hybrid drive mode. Specifically, engine-assisted drive mode means that when the drive motor output is limited, the engine directly participates in driving the vehicle through clutch engagement, and compensates for the torque loss of the drive motor through a power distribution strategy, maintaining the vehicle's driving force at a reasonable level, ensuring driving continuity, and reducing the thermal load on the drive motor.

[0064] The aforementioned preset duty cycle represents the fixed maximum output value of the motor water pump duty cycle and the cooling fan duty cycle set to enhance cooling capacity. It is usually 100% to ensure that the cooling system operates at maximum capacity.

[0065] The aforementioned first torque threshold represents the maximum torque limit that the drive motor can output when the drive motor fault level is slightly over-temperature. The first torque threshold is not a fixed value, but is determined by the drive motor's rated torque, the first temperature coefficient, and the drive motor's safe torque. The minimum value among the three is taken as the actual limit to ensure that the output torque does not exceed the motor's design capacity or the safety boundary under the current thermal state.

[0066] The aforementioned first temperature coefficient represents the power reduction factor dynamically calculated based on the drive motor temperature when the drive motor fault level is slightly over-temperature. Its value ranges from 0.5 to 0.7, gradually decreasing as the drive motor temperature increases. It is used to quantify the attenuation effect of temperature on the motor's output capability. Its calculation is based on a preset temperature-coefficient mapping relationship or function curve to ensure strict matching between torque limits and thermal conditions. For example, the closer the temperature is to the first or second temperature threshold, the closer the first temperature coefficient is to 0.5, indicating a lower permissible motor torque output. When the temperature is in a lower over-temperature range, such as 105°C, the first temperature coefficient can approach 0.7 to maintain a higher auxiliary driving force.

[0067] When the system detects that the drive motor is slightly overheated, it executes the following coordinated control actions: First, the cooling system's water pump and fan operate at a preset high-efficiency duty cycle to maximize heat dissipation. Second, the drive motor's output torque is forcibly limited to a first torque threshold determined by the minimum of the drive motor's rated torque, the temperature reduction factor corresponding to the current temperature, and the real-time calculated safe torque. Simultaneously, the vehicle's drive mode is switched to engine-assisted drive mode, allowing the engine to actively intervene and provide drive force compensation. This achieves a precise, dynamic, and multi-dimensional response to slight overheating without interrupting vehicle operation. It proactively reduces the motor's thermal load, improves cooling efficiency, and introduces an external power source for coordinated output, effectively avoiding a decline in driving experience due to simple torque reduction, while preventing further temperature increases that could lead to more serious malfunctions.

[0068] Based on the above optional embodiments, the embodiments of this application realize a mild overheating response mechanism that maintains basic heat dissipation capacity through the cooling system, dynamically limits the output torque of the drive motor to adapt to temperature, and smoothly switches the power source from motor main drive to engine auxiliary drive under slight overheating conditions. This mechanism constructs a multi-parameter coordinated, thermal load driven, and output capacity precisely constrained mild overheating response mechanism, thereby effectively controlling the temperature rise rate of the drive motor and preventing further deterioration of the thermal state without interrupting vehicle operation.

[0069] Optionally, the vehicle drive mode further includes: an engine-primed drive mode, wherein the vehicle control operation is determined based on the drive motor fault level, including: in response to the drive motor fault level being a slight overheating level, controlling the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque being less than or equal to a second torque threshold, and controlling the vehicle drive mode to be an engine-primed drive mode, wherein the second torque threshold is determined based on the drive motor rated torque, a second temperature coefficient, and the drive motor safe torque, the second temperature coefficient being less than a first temperature coefficient, and the engine-primed drive mode is used to indicate that the engine provides the main driving force.

[0070] The aforementioned engine-driven mode indicates that when the output capacity of the drive motor is limited but still retains some capacity, the engine engages through the clutch to bear the main driving torque of the vehicle, while the drive motor only provides limited auxiliary output. The vehicle's power is a coordinated operation state in which the engine is the main force and the drive motor is the auxiliary force. In this mode, the output of the drive motor is strictly limited to reduce its thermal load, while the engine takes the lead in maintaining the vehicle's driving performance.

[0071] The aforementioned second temperature coefficient represents the power reduction factor dynamically calculated based on the drive motor temperature when the drive motor fault level is mild overheating. Its value ranges from 0.2 to 0.4, gradually decreasing as the drive motor temperature increases. It is used to quantify the attenuation effect of temperature on the motor's output capability, and its calculation is based on a preset temperature-coefficient mapping relationship or function curve. Furthermore, the value of the second temperature coefficient is less than that of the first temperature coefficient, indicating that under the mild overheating level, the system's limitation on the motor's output capability is more stringent than under the slight overheating level, to cope with higher thermal load risks. For example, when the temperature reaches above the fourth temperature threshold, the second temperature coefficient may drop to 0.2, allowing only a very small proportion of torque output to ensure rapid motor cooling.

[0072] The aforementioned second torque threshold represents the maximum allowable torque limit for the drive motor output when the drive motor fault level is mild overtemperature. This value is not fixed but is determined jointly by the drive motor's rated torque, the second temperature coefficient, and the drive motor's safe torque. The minimum of these three factors is taken as the actual limit to ensure that the output torque neither exceeds the motor's design capacity nor exceeds the safety boundary under the current thermal state. Since the second temperature coefficient is less than the first temperature coefficient, the second torque threshold is lower than the first torque threshold, indicating that the maximum allowable torque output of the drive motor is further reduced under mild overtemperature conditions to achieve more stringent thermal load control.

[0073] When the system detects that the drive motor has entered a slightly overheated state, it executes the following coordinated control actions: First, it maintains the motor water pump and cooling fan running continuously at a preset duty cycle to ensure that the cooling system maintains efficient heat dissipation capacity under high heat load. Second, it forcibly limits the output torque of the drive motor to a second torque threshold determined by the minimum value among the drive motor's rated torque, the second temperature coefficient, and the drive motor's safe torque. Since the second temperature coefficient is less than the first temperature coefficient, this limit is lower than the first torque threshold under the slightly overheated level, achieving stricter torque constraints. Simultaneously, it switches the vehicle's drive mode to engine-driven mode, allowing the engine to bear the main driving torque, while the drive motor retains only a very small amount of auxiliary output capability to minimize its heat generation.

[0074] Based on the above optional embodiments, this application embodiment achieves a precise and gradual response to slightly overheated conditions by reducing the output capacity of the motor, enhancing the cooling capacity, and actively transferring the power control to the engine. While preventing further deterioration of the thermal condition, it ensures that the vehicle has a high level of power maintenance capability and avoids the interruption of driving experience due to excessive torque reduction, thereby achieving a better balance between thermal safety and power performance.

[0075] Optionally, the vehicle drive mode further includes: an engine drive mode, wherein the vehicle control operation is determined based on the drive motor fault level, including: in response to the drive motor fault level being a moderate overheat level, controlling the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, and controlling the vehicle drive mode to be an engine drive mode, wherein the engine drive mode is used to indicate that the engine provides all the driving force to the vehicle.

[0076] The aforementioned engine drive mode indicates that when the output capacity of the drive motor is severely limited, the engine engages through the clutch to fully assume the entire driving torque output of the vehicle, and the drive motor stops outputting torque and enters a non-drive state. In this mode, the power of the entire vehicle is provided entirely by the engine to ensure that the vehicle still has the ability to drive continuously when the thermal condition of the drive motor is abnormal.

[0077] The aforementioned preset output torque represents the target output torque value of the drive motor forcibly set by the HCU when the drive motor fault level is moderate overheating. This value can be zero, indicating that the drive motor completely stops outputting power to completely eliminate its own heat source and prevent it from continuing to bear load under high heat conditions, which would cause the temperature to rise further. The aforementioned preset output torque is a fixed value and does not change with vehicle speed, load, or temperature fluctuations. Its setting is based on the thermal safety boundary corresponding to the moderate overheating level, ensuring that the drive motor enters a completely stationary state and achieves forced isolation of thermal load.

[0078] When the system detects that the drive motor has entered a moderate overheating state, it executes the following coordinated control actions: First, it maintains the motor water pump and cooling fan running continuously at a preset duty cycle to ensure that the motor body and inverter can still obtain effective heat dissipation after power failure. Second, it sets the drive motor output torque to a preset output torque, i.e., zero torque, completely cutting off its power output and eliminating its continuous contribution as a heat source. At the same time, it switches the vehicle drive mode to engine drive mode, allowing the engine to engage through the clutch and fully bear all the vehicle's driving torque, ensuring that the vehicle's power continuity is not interrupted.

[0079] Based on the above optional embodiments, the embodiments of this application realize a smooth, safe, and deterministic switch from electric drive main drive to engine main drive without relying on driver intervention. This effectively prevents irreversible damage such as thermal runaway, insulation breakdown, or permanent magnet demagnetization caused by continuous operation of the drive motor. Thus, in the case of moderate overheating faults, it achieves complete physical isolation of the drive motor and seamless takeover of the vehicle's power, ensuring vehicle driving safety and system integrity.

[0080] Optionally, the vehicle drive mode also includes an engine drive mode, and the vehicle status information also includes the power battery voltage. Based on the drive motor fault level, the vehicle control operation is determined to include: in response to the drive motor fault level being a severe overheating level, controlling the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, the vehicle drive mode to engine drive mode, and controlling the target vehicle speed to be less than a preset speed threshold, wherein the target vehicle speed is determined based on the power battery voltage and a preset mapping table, and the preset mapping table is used to represent the mapping relationship between the power battery voltage and the preset speed threshold.

[0081] The aforementioned power battery voltage represents the terminal voltage value of the power battery pack connected to the drive motor under the current operating state. It reflects the current state of charge and internal resistance characteristics of the battery and can directly affect the magnitude of the weak magnetic current generated by the back electromotive force when the drive motor has no output torque.

[0082] The aforementioned preset speed threshold represents the maximum permissible vehicle speed calculated and set by the HCU based on the power battery voltage using a preset mapping table when the drive motor fault level is severe overheating. The value is derived from the power battery voltage, gear ratio, and tire radius; for example, it corresponds to 90 km / h when the power battery voltage is 200V, and 120 km / h when it is 300V or higher. This preset speed threshold is a dynamic limit, not a fixed value, used to prevent the drive motor from generating a weak magnetic current exceeding the safety boundary due to excessive speed during engine drag, thereby avoiding overheating and damage to the inverter due to continuous high current operation.

[0083] The aforementioned preset mapping table represents a two-dimensional data table, determined in advance through bench testing and simulation modeling, used to describe the correspondence between the power battery voltage and a preset speed threshold. Each set of power battery voltage values ​​in the table corresponds to a safe upper limit vehicle speed value. This mapping relationship is established based on the back electromotive force characteristics of the drive motor, the inverter's current handling capability, and a heat dissipation model, ensuring that under different battery voltages, the speed of the drive motor is limited below the critical point that will not cause the inverter to overheat. Table 2 below shows a preset mapping table according to an embodiment of this application.

[0084] Table 2

[0085]

[0086] In actual limp control, in addition to protecting the generator, the user experience of limping the vehicle must also be taken into account. Therefore, the preset mapping table can be optimized as shown in Table 3 below:

[0087] Table 3

[0088]

[0089] When the system detects that the drive motor has entered a severe overheating state, it executes the following coordinated control actions: First, it maintains the motor water pump and cooling fan running continuously at a preset duty cycle to ensure that the motor body and inverter can still obtain effective heat dissipation after power failure. Second, it sets the drive motor output torque to a preset output torque, i.e., zero torque, completely cutting off its power output and eliminating its continuous contribution as a heat source. At the same time, it switches the vehicle drive mode to engine drive mode, allowing the engine to engage through the clutch and bear all the drive torque. Based on this, according to the real-time detected power battery voltage, it queries a preset mapping table to dynamically determine the target vehicle speed and implement speed limiting control to ensure that the speed generated by the drive motor under the engine's reverse drag does not exceed the preset speed threshold under the corresponding voltage, thereby avoiding the inverter temperature from continuously rising due to the large weak magnetic current generated at high speed.

[0090] Based on the above optional embodiments, the embodiments of this application realize the active blocking of the fault chain of "engine reverse drag → high speed → strong and weak magnetic current → inverter overheating" under extreme working conditions of severe overheating and possible failure of the cooling system. While ensuring that the vehicle has the ability to limp home, it completely eliminates the risk of secondary burnout of the inverter due to the lack of protection strategy.

[0091] Optionally, the vehicle status information also includes: communication status. The vehicle control method further includes: in response to a communication failure, controlling the duty cycle of the motor water pump to a preset duty cycle, the duty cycle of the cooling fan to a preset duty cycle, the output torque of the drive motor to a preset output torque, the vehicle driving mode to engine driving mode, the target vehicle speed to be less than a preset speed threshold, and generating a prompt message and sending the prompt message to the graphical user interface.

[0092] The communication status described above indicates the connectivity and validity of data interaction between the HCU and the drive motor controller via the controller area network. When the communication status is a communication failure, the HCU cannot normally receive temperature signals, torque feedback signals, or status flags sent by the drive motor controller, or cannot send control commands to it. Fault types include checksum errors, livecounter timeouts, message timeouts, data frame loss, or communication link interruptions.

[0093] The above-mentioned prompts are text or icon-based warnings generated by the HCU to convey abnormal vehicle system status to the driver. These warnings include, but are not limited to, semantically clear statements such as "drive motor communication abnormality," "power system limited," and "please avoid aggressive driving." They are used to proactively remind the driver in the graphical user interface that the vehicle is currently in a degraded operating state and that cautious driving behavior is required.

[0094] The aforementioned graphical user interface refers to the human-machine interface installed on the vehicle's dashboard or central control screen, which allows the driver to view the vehicle's operating status and fault prompts. It supports the presentation of prompt information through text, icons, color changes, and other methods to ensure the intuitiveness and timeliness of information delivery.

[0095] When the HCU detects a communication failure with the drive motor controller (i.e., unable to obtain drive motor temperature, torque feedback, or status confirmation information), the system immediately activates fail-safe strategies. These strategies include: maintaining the motor water pump and cooling fan operating continuously at a preset duty cycle to ensure the drive motor and inverter have basic heat dissipation capabilities even when the temperature is unknown; setting the drive motor output torque to a preset zero torque, blocking any possible power output; switching the vehicle drive mode to engine drive mode, with the engine independently handling all drive torque; limiting the vehicle's maximum speed according to a default preset speed threshold to prevent inverter overheating due to excessive reverse drag speed; and generating a warning message with clear fault semantics, proactively alerting the driver through the graphical user interface. In other words, in the event of a communication failure, the system executes a severe overheating strategy, generates a warning message, and then sends it to the graphical user interface.

[0096] Based on the above optional embodiments, in the extreme failure scenario of communication link interruption, the embodiments of this application can immediately trigger multi-level protection actions based on conservative safety assumptions without relying on any external feedback, realizing automatic response of the entire chain from failure detection to protection execution, effectively avoiding system loss of control, motor burnout or complete loss of vehicle power due to information loss, and significantly improving the fault tolerance and operational safety of the hybrid power system under abnormal communication conditions.

[0097] In one optional embodiment, provided that the drive motor temperature does not trigger any over-temperature protection threshold (i.e., the system is at the normal drive motor temperature level), the HCU does not interfere with the power output logic, maintaining the original torque coordination distribution relationship between the engine, drive motor, and generator to ensure that the vehicle's power response and energy efficiency are maintained at their optimal levels. Simultaneously, based on multi-dimensional temperature and operating parameters, including drive motor body temperature, inverter temperature, motor coolant temperature, coolant flow rate, and ambient temperature, the HCU dynamically calculates and adjusts the duty cycle of the motor water pump to adapt the coolant flow rate to the current heat load, avoiding excessive energy consumption. Furthermore, combining the motor coolant temperature, ambient temperature, and vehicle speed, the HCU dynamically adjusts the duty cycle of the cooling fan, prioritizing reduced fan operating intensity to decrease power consumption and noise while ensuring sufficient heat dissipation capacity. This achieves adaptive and refined operation of the cooling system under all operating conditions, ensuring that the drive motor remains within its thermal safety range under normal operating conditions, while simultaneously optimizing the vehicle's energy management efficiency and noise and vibration performance.

[0098] Figure 3This is a schematic diagram of an optional vehicle control method according to an embodiment of this application, such as... Figure 3 As shown. This method uses the HCU as its core and integrates a motor water temperature sensor, motor controller 1 (drive motor controller), motor controller 2 (generator controller), battery management system, engine management system, fan, water pump, and clutch. Each of these assembly controllers monitors and identifies its own fault status in real time and sends this information to the HCU via the CAN bus. The HCU receives relevant component and fault information from the engine, drive motor, generator, and battery controllers, identifies the clutch and its own status and faults, and sends control commands to the relevant controllers to coordinate the orderly operation of all components, achieving hybrid drive and regenerative braking functions, and ensuring the vehicle operates safely and reliably according to the driver's needs in the event of a fault.

[0099] Figure 4 This is a schematic diagram of another optional vehicle control method according to an embodiment of this application, such as... Figure 4 As shown, the logic system of HCU implementing differentiated control based on the thermal state of the drive motor is presented. During the over-temperature protection process of HCU according to the over-temperature level, when HCU identifies that the drive motor is within the normal temperature range, that is, the drive motor body temperature does not exceed the ninth temperature threshold, the inverter temperature does not exceed the tenth temperature threshold, and the motor coolant temperature does not exceed the ninth temperature threshold, the system maintains the current torque distribution and power source coordination strategy, and controls the fan and water pump to ensure cooling demand, but does not perform any derating intervention. Specifically, based on multi-dimensional parameters such as drive motor body temperature, inverter temperature, motor coolant temperature, coolant flow rate, and ambient temperature, the duty cycle of the motor water pump is dynamically adjusted to match the coolant circulation flow rate required by the current heat load, and the duty cycle of the cooling fan is comprehensively judged by combining coolant temperature, ambient temperature, and vehicle speed to achieve a balance between energy-saving operation and efficient heat dissipation of the cooling system under low load conditions.

[0100] When the drive motor is detected to be in a slightly over-temperature state, i.e., the body temperature does not exceed the first temperature threshold or the inverter temperature does not exceed the second temperature threshold, the HCU will increase the duty cycle of the motor water pump and cooling fan to the maximum, and at the same time limit the output torque of the drive motor to within the first torque threshold. This threshold is determined by the minimum value among the drive motor rated torque, the first temperature coefficient and the drive motor safe torque. The remaining power demand is compensated by the engine to achieve a smooth power transition.

[0101] When the drive motor enters a slightly overheated state, i.e., the body temperature is greater than or equal to the third temperature threshold or the inverter temperature is greater than or equal to the fourth temperature threshold, the HCU continues to keep the cooling system running at full load, increases the duty cycle of the motor water pump and cooling fan to the maximum, and further reduces the drive motor torque limit to the second torque threshold. This threshold is calculated based on a more stringent second temperature coefficient and is less than the first torque threshold. At the same time, the vehicle drive mode is switched to engine main drive mode, where the engine takes the lead in driving and the drive motor only provides limited auxiliary output.

[0102] When the drive motor enters the intermediate overheat level, that is, when the body temperature is greater than or equal to the fifth temperature threshold or the inverter temperature is greater than or equal to the sixth temperature threshold, the HCU maintains the cooling system at full power, increases the duty cycle of the motor water pump and cooling fan to the maximum, and forces the drive motor output torque to be set to zero, completely cutting off the motor power output, so that the engine drives the vehicle independently, ensuring the vehicle's basic driving capability.

[0103] When the drive motor enters the severe overheating level, that is, when the body temperature is greater than or equal to the seventh temperature threshold or the inverter temperature is greater than or equal to the eighth temperature threshold, the HCU, based on the above-mentioned zero torque and independent engine drive, queries a preset mapping table according to the power battery voltage, dynamically sets the target vehicle speed and implements speed limit control, limiting the vehicle speed to within the preset speed threshold under the corresponding voltage, in order to prevent the drive motor from generating excessive back electromotive force and large weak magnetic current under the reverse drag of the engine, thereby avoiding secondary overheating damage to the inverter due to continuous overcurrent, and at the same time, an instrument alarm is triggered.

[0104] The above strategy constructs a complete protection chain from conventional cooling regulation, gradual torque derating, and power source switching to limit vehicle speed by accurately mapping multi-level fault classification and corresponding control actions. While ensuring the safety of the drive motor, it maximizes the maintenance of vehicle driving performance and driver experience, achieving a strategic leap from local component protection to whole vehicle system-level fault tolerance.

[0105] Figure 5 This is a structural block diagram of an optional vehicle control device according to an embodiment of this application, such as... Figure 5 As shown, the device includes: an acquisition module 501 for acquiring vehicle status information, wherein the vehicle status information represents the real-time operating status of the vehicle; a first determination module 502 for determining the drive motor fault level based on the vehicle status information and a preset temperature threshold, wherein the drive motor fault level is used to determine the degree of overheating of the drive motor; a second determination module 503 for determining vehicle control operations based on the drive motor fault level; and a protection module 504 for performing overheat protection on the drive motor based on the vehicle control operations.

[0106] Optionally, the vehicle status information includes: drive motor temperature and inverter temperature. The first determining module 502 is further configured to: determine the drive motor fault level as a slight overheating level in response to the drive motor temperature being less than or equal to a first temperature threshold, or the inverter temperature being less than or equal to a second temperature threshold, wherein the first temperature threshold is greater than the second temperature threshold; or, determine the drive motor fault level as a slight overheating level in response to the drive motor temperature being greater than or equal to a third temperature threshold, or the inverter temperature being greater than or equal to a fourth temperature threshold, wherein the third temperature threshold is greater than the first temperature threshold and the fourth temperature threshold is greater than the third temperature threshold; or, determine the drive motor fault level as a moderate overheating level in response to the drive motor temperature being greater than or equal to a fifth temperature threshold, or the inverter temperature being greater than or equal to a sixth temperature threshold, wherein the fifth temperature threshold is greater than the sixth temperature threshold and the sixth temperature threshold is greater than the fourth temperature threshold; or, determine the drive motor fault level as a severe overheating level in response to the drive motor temperature being greater than or equal to a seventh temperature threshold, or the inverter temperature being greater than or equal to an eighth temperature threshold, wherein the seventh temperature threshold is greater than the eighth temperature threshold and the eighth temperature threshold is greater than the fifth temperature threshold.

[0107] Optionally, the vehicle status information also includes: motor water pump duty cycle, cooling fan duty cycle, drive motor output torque, drive motor rated torque, drive motor safe torque, and vehicle drive mode. The vehicle drive mode includes: engine-assisted drive mode. The second determining module 503 is further configured to: in response to the drive motor fault level being a slight over-temperature level, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, and the drive motor output torque being less than or equal to a first torque threshold, and control the vehicle drive mode to engine-assisted drive mode. The first torque threshold is determined based on the drive motor rated torque, a first temperature coefficient, and the drive motor safe torque. The first temperature coefficient is determined based on the drive motor temperature. The engine-assisted drive mode is used to indicate that the engine provides driving force compensation.

[0108] Optionally, the vehicle drive mode further includes: an engine main drive mode. The second determining module 503 is also used to: in response to the drive motor fault level being a slight overheating level, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, and the drive motor output torque being less than or equal to a second torque threshold, and control the vehicle drive mode to the engine main drive mode, wherein the second torque threshold is determined based on the drive motor rated torque, a second temperature coefficient, and the drive motor safe torque, the second temperature coefficient being less than a first temperature coefficient, and the engine main drive mode is used to indicate that the engine provides the main driving force.

[0109] Optionally, the vehicle drive mode further includes an engine drive mode. The second determining module 503 is also configured to: in response to the drive motor fault level being a moderate overheat level, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, and control the vehicle drive mode to an engine drive mode, wherein the engine drive mode is used to indicate that the engine provides all the driving force to the vehicle.

[0110] Optionally, the vehicle driving mode further includes an engine driving mode, and the vehicle status information further includes the power battery voltage. The second determining module 503 is also used to: in response to the drive motor fault level being a severe overheating level, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, the vehicle driving mode to an engine driving mode, and control the target vehicle speed to be less than a preset speed threshold, wherein the target vehicle speed is determined based on the power battery voltage and a preset mapping table, and the preset mapping table is used to represent the mapping relationship between the power battery voltage and the preset speed threshold.

[0111] Optionally, the vehicle status information also includes: communication status. The vehicle control device further includes: a third determining module 505, used to: in response to a communication failure, control the motor water pump duty cycle to a preset duty cycle, the cooling fan duty cycle to a preset duty cycle, the drive motor output torque to a preset output torque, the vehicle drive mode to engine drive mode, the target vehicle speed to be less than a preset speed threshold, and generate a prompt message and send the prompt message to the graphical user interface.

[0112] According to another aspect of the embodiments of this application, a vehicle is also provided, including: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to execute instructions to implement the vehicle control methods in various embodiments of this application.

[0113] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored executable program, wherein, when the executable program is running, it controls the device where the computer-readable storage medium is located to execute the vehicle control method of various embodiments of this application.

[0114] According to another aspect of the embodiments of this application, a computer program product is also provided, including computer instructions that, when executed by a processor, implement the methods in various embodiments of this application.

[0115] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0116] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0117] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0118] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0119] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0120] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0121] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A vehicle control method, characterized in that, include: Obtain vehicle status information, wherein the vehicle status information is used to represent the real-time operating status of the vehicle; Based on the vehicle status information and the preset temperature threshold, the drive motor fault level is determined, wherein the drive motor fault level is used to determine the degree of overheating of the drive motor. Based on the fault level of the drive motor, determine the vehicle control operation; Based on the aforementioned vehicle control operations, over-temperature protection is provided for the drive motor.

2. The vehicle control method according to claim 1, characterized in that, The vehicle status information includes: drive motor temperature and inverter temperature. Determining the drive motor fault level based on the vehicle status information and a preset temperature threshold includes: In response to the drive motor temperature being less than or equal to a first temperature threshold, or the inverter temperature being less than or equal to a second temperature threshold, the drive motor fault level is determined to be a slight overtemperature level, wherein the first temperature threshold is greater than the second temperature threshold; or, In response to the drive motor temperature being greater than or equal to a third temperature threshold, or the inverter temperature being greater than or equal to a fourth temperature threshold, the drive motor fault level is determined to be a slight overheating level, wherein the third temperature threshold is greater than the first temperature threshold, and the fourth temperature threshold is greater than the third temperature threshold; or, In response to the drive motor temperature being greater than or equal to a fifth temperature threshold, or the inverter temperature being greater than or equal to a sixth temperature threshold, the drive motor fault level is determined to be a moderate overheating level, wherein the fifth temperature threshold is greater than the sixth temperature threshold, and the sixth temperature threshold is greater than the fourth temperature threshold; or, In response to the drive motor temperature being greater than or equal to a seventh temperature threshold, or the inverter temperature being greater than or equal to an eighth temperature threshold, the drive motor fault level is determined to be a severe overtemperature level, wherein the seventh temperature threshold is greater than the eighth temperature threshold, and the eighth temperature threshold is greater than the fifth temperature threshold.

3. The vehicle control method according to claim 2, characterized in that, The vehicle status information also includes: motor water pump duty cycle, cooling fan duty cycle, drive motor output torque, drive motor rated torque, drive motor safe torque, and vehicle drive mode. The vehicle drive mode includes: engine-assisted drive mode. Determining vehicle control operations based on the drive motor fault level includes: In response to the drive motor fault level being the slight overtemperature level, the duty cycle of the motor water pump is controlled to a preset duty cycle, the duty cycle of the cooling fan is controlled to the preset duty cycle, the output torque of the drive motor is less than or equal to a first torque threshold, and the vehicle drive mode is controlled to the engine-assisted drive mode. The first torque threshold is determined based on the rated torque of the drive motor, a first temperature coefficient, and the safe torque of the drive motor. The first temperature coefficient is determined based on the temperature of the drive motor. The engine-assisted drive mode indicates that the engine provides driving force compensation.

4. The vehicle control method according to claim 3, characterized in that, The vehicle drive mode also includes: engine main drive mode, and the step of determining the vehicle control operation based on the drive motor fault level includes: In response to the drive motor fault level being the slight overtemperature level, the duty cycle of the motor water pump is controlled to be the preset duty cycle, the duty cycle of the cooling fan is controlled to be the preset duty cycle, the output torque of the drive motor is less than or equal to a second torque threshold, and the vehicle drive mode is controlled to be the engine main drive mode, wherein the second torque threshold is determined based on the rated torque of the drive motor, a second temperature coefficient, and the safe torque of the drive motor, the second temperature coefficient is less than the first temperature coefficient, and the engine main drive mode is used to indicate that the engine provides the main driving force.

5. The vehicle control method according to claim 4, characterized in that, The vehicle drive mode further includes: an engine drive mode, wherein determining the vehicle control operation based on the drive motor fault level includes: In response to the drive motor fault level being the moderate overheat level, the duty cycle of the motor water pump is controlled to the preset duty cycle, the duty cycle of the cooling fan is controlled to the preset duty cycle, the output torque of the drive motor is controlled to the preset output torque, and the vehicle drive mode is controlled to the engine drive mode, wherein the engine drive mode is used to indicate that the engine provides all the driving force to the vehicle.

6. The vehicle control method according to claim 5, characterized in that, The vehicle drive mode further includes: engine drive mode; the vehicle status information further includes: power battery voltage; and determining the vehicle control operation based on the drive motor fault level includes: In response to the drive motor fault level being the severe overheating level, the duty cycle of the motor water pump is controlled to be the preset duty cycle, the duty cycle of the cooling fan is controlled to be the preset duty cycle, the output torque of the drive motor is controlled to be the preset output torque, the vehicle driving mode is controlled to be the engine driving mode, and the target vehicle speed is controlled to be less than a preset speed threshold. The target vehicle speed is determined based on the power battery voltage and a preset mapping table, and the preset mapping table is used to represent the mapping relationship between the power battery voltage and the preset speed threshold.

7. The vehicle control method according to claim 6, characterized in that, The vehicle status information also includes: communication status, and the method further includes: In response to a communication failure, the system controls the duty cycle of the motor water pump to the preset duty cycle, the duty cycle of the cooling fan to the preset duty cycle, the output torque of the drive motor to the preset output torque, the vehicle drive mode to the engine drive mode, the target vehicle speed to be less than the preset speed threshold, and generates a prompt message, which is then sent to the graphical user interface.

8. A vehicle, characterized in that, include: processor; Memory used to store the processor's executable instructions; The processor is configured to execute the instructions to implement the vehicle control method according to any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored executable program, wherein, when the executable program is executed, it controls the device on which the storage medium is located to perform the vehicle control method according to any one of claims 1 to 7.

10. A computer program product, characterized in that, The computer program product includes computer instructions that, when executed by a processor, implement the vehicle control method as described in any one of claims 1 to 7.

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