Wheel end intelligent thermal management system for electrically-driven truck and control method

Abstract

The invention discloses a wheel end intelligent thermal management system for an electrically-driven truck and a control method, and relates to the technical field of thermal management of electrically-driven trucks, in particular to the wheel end intelligent thermal management system for the electrically-driven truck and the control method, and the system comprises a sensing layer, a decision-making layer, an execution layer and an interaction layer, the sensing layer collects data such as wheel end temperature and brake pressure through various sensors, an intelligent heat management controller of the decision-making layer fuses multi-source information and executes a control algorithm, the execution layer is provided with an active air cooling subsystem, a precise fog cooling subsystem and a liquid cooling heat management subsystem, and the interaction layer communicates with a whole vehicle related system through a high-speed CAN bus. According to the control method, a layered progressive cooling strategy is executed through multi-source information collection and fusion, thermal power calculation and temperature prediction, and a waste heat recovery cooperative control mechanism, a safety arbitration mechanism and a fault safety mechanism are further arranged. According to the system and method, the wheel end temperature can be accurately regulated, braking safety is guaranteed, waste heat is recycled for battery heat preservation, and the running reliability and energy efficiency of a vehicle are improved.

Description

Technical Field

[0001] This invention relates to the field of thermal management technology for electric-drive trucks, specifically to an intelligent thermal management system and control method for wheel ends of electric-drive trucks. Background Technology

[0002] With the rapid development of the new energy vehicle industry, electric-drive trucks (including pure electric trucks and plug-in hybrid trucks) are increasingly widely used in logistics transportation, urban delivery and other fields due to their advantages of being environmentally friendly and having low energy consumption. However, compared with traditional fuel trucks, electric-drive trucks have significant differences in power transmission structure and braking methods, and the thermal management challenges faced by the wheel-end braking system are more prominent.

[0003] Electric-drive trucks typically rely on a combination of electric motor braking and mechanical braking. Under conditions such as long downhill slopes, heavy loads, and frequent starts and stops, the mechanical braking system must continuously engage to ensure driving safety. The intense friction between the brake discs and pads generates a significant amount of heat. Due to the compact chassis layout of electric-drive trucks, the wheel-end cooling environment is limited, leading to heat accumulation and a rapid increase in brake disc temperature. When the temperature exceeds a critical value, brake fade occurs, manifesting as decreased braking efficiency, increased braking distance, and in severe cases, even brake failure, posing a significant safety hazard. Simultaneously, excessively high wheel-end temperatures can also be conducted to components such as tires and wheel bearings, accelerating rubber aging and bearing wear, shortening component lifespan, and increasing vehicle maintenance costs.

[0004] Currently, most electric trucks rely on passive cooling for wheel-end cooling, with some models equipped with simple forced air cooling systems. However, these systems generally suffer from low cooling efficiency and insufficient control precision. Passive cooling depends on natural convection, which cannot quickly respond to sudden changes in braking heat load. Traditional forced air cooling lacks intelligent adjustment mechanisms; the fan speed is fixed, making it difficult to accurately match cooling needs based on actual temperature changes. This results in either energy waste at low temperatures or failure to meet cooling requirements at high temperatures. Furthermore, existing technologies do not adequately consider the recovery and utilization of braking waste heat, allowing a large amount of heat generated during braking to be directly dissipated into the environment, causing energy waste. Additionally, the driving range of electric truck batteries decreases significantly in low-temperature environments, requiring additional electrical energy to heat the batteries, further exacerbating the conflict between energy consumption and range anxiety.

[0005] Meanwhile, the safety and reliability of existing wheel-end thermal management systems need improvement. Some systems lack comprehensive fault response mechanisms, and when sensors fail, actuators malfunction, or communication is interrupted, problems such as inaccurate temperature monitoring and cooling failure are likely to occur. Furthermore, the cooling strategy lacks coordination with other vehicle systems (such as the battery management system and vehicle controller), making it difficult to achieve efficient waste heat recovery while ensuring braking safety. In plug-in hybrid electric vehicles, the waste heat during internal combustion engine startup is not effectively utilized, and the wheel-end thermal management system has poor adaptability when switching between different power modes, failing to meet the dual requirements of braking safety and energy conservation.

[0006] Therefore, developing a wheel-end intelligent thermal management system and control method with precise temperature control, intelligent regulation, waste heat recovery and high reliability to solve problems such as overheating of wheel ends, low heat dissipation efficiency and energy waste in electric-driven trucks has become a technical bottleneck that urgently needs to be overcome in the field of new energy trucks. Summary of the Invention

[0007] The purpose of this invention is to provide an intelligent thermal management system and control method for wheel ends of electric-driven trucks. Through multi-source sensing, layered cooling, waste heat recovery and fault safety mechanisms, the system can accurately regulate wheel end temperature, avoid the risk of brake fade, recover brake waste heat to keep the battery warm, and improve vehicle braking safety, operational reliability and energy utilization efficiency.

[0008] To achieve the above objectives, the present invention provides the following technical solution: an intelligent thermal management system and control method for the wheel end of an electrically driven truck, comprising four core functional layers: a perception layer, a decision-making layer, an execution layer, and an interaction layer. Each layer works in concert to achieve intelligent control of wheel end thermal management. The perception layer deploys various dedicated sensing devices to collect real-time operational data related to the wheel end thermal state, such as wheel end brake disc temperature, brake line pressure, tire surface temperature, ambient temperature, vehicle speed, vehicle load, and road gradient, ensuring comprehensive and real-time data collection. The decision-making layer is an independently configured intelligent thermal management controller with a built-in dedicated data processing module and control logic unit. It can fuse, analyze, and filter multi-source heterogeneous information collected by the perception layer, and execute preset control algorithms to generate precise control commands. The execution layer includes an active air-cooling subsystem, a precision fog-cooling subsystem, and a liquid-cooled thermal management subsystem. The three subsystems can work independently or collaboratively according to the control commands to achieve heat dissipation and thermal management functions of different intensities. The interaction layer is equipped with a high-speed CAN bus communication module, which establishes a stable bidirectional communication connection with the vehicle controller (VCU), battery management system (BMS), and anti-lock braking system (ABS) through a standardized communication protocol, realizing data interaction and command transmission between systems and ensuring the coordination of vehicle thermal management and driving safety.

[0009] Furthermore, the active air-cooling subsystem consists of a high-speed centrifugal fan and an intelligent air deflector, which work together mechanically to achieve directional and efficient heat dissipation. The rated power of the high-speed centrifugal fan is set between 150W and 250W, and the output power can be adjusted according to the actual heat dissipation requirements. Its maximum airflow is not less than 30m³ / min, which can provide sufficient cooling airflow to the wheel ends. The intelligent air deflector is made of aerospace aluminum alloy in one piece, which has lightweight, high strength and good thermal conductivity and heat dissipation performance. The air deflector is embedded with electrically adjustable air deflector plates. The deflection angle of the air deflector plates is controlled by the drive motor. It can dynamically adjust the air outlet angle and airflow direction in real time according to the oncoming wind speed corresponding to the vehicle's driving direction and speed and the heat distribution at the wheel ends, ensuring that the cooling airflow accurately acts on the core heat-generating components such as the brake disc, thereby improving heat dissipation efficiency.

[0010] Furthermore, the precision mist cooling subsystem includes piezoelectric ceramic atomizing nozzles, a stainless steel reservoir, and a miniature magnetically driven diaphragm pump. These components are connected via pipelines to form a closed-loop operating system. Each wheel-end brake is equipped with 2 to 4 piezoelectric ceramic atomizing nozzles, evenly distributed around the outer circumference of the brake disc. These nozzles utilize the piezoelectric effect to break the liquid transported from the reservoir into ultrafine droplets of 5 to 20 micrometers. These droplets quickly adhere to the brake disc surface and evaporate, absorbing heat and achieving efficient cooling. The stainless steel reservoir has a capacity of 8 to 12 liters to meet the coolant storage requirements for long-distance driving. The reservoir integrates a level sensor and an electric heater. The level sensor monitors the coolant level in real time and feeds it back to the controller. The electric heater automatically activates when the ambient temperature is below 0°C, maintaining the coolant temperature above the freezing point and ensuring the system operates normally in low-temperature environments, providing reliable antifreeze functionality.

[0011] Furthermore, the liquid-cooled thermal management subsystem includes a 3D-printed liquid-cooled heat exchanger, a plate heat exchanger, and a three-way reversing valve, which achieves heat transfer and distribution through coolant circulation. The 3D-printed liquid-cooled heat exchanger is made using metal powder 3D printing technology. Its structure is precisely adapted to the internal space of the brake drum and is directly integrated inside the brake drum. The heat exchange surface of the heat exchanger is in close contact with the inner wall of the brake drum, which can quickly capture the heat flow generated during braking and has high heat exchange efficiency. The plate heat exchanger is used to realize the heat exchange between the coolant and the external heat dissipation medium. The three-way reversing valve is an electromagnetically controlled reversing valve. The valve core is switched by the electrical signal issued by the controller, which can realize the rapid switching between the heat dissipation circuit and the waste heat recovery circuit, thereby flexibly adjusting the heat distribution ratio between the radiator and the battery coolant, which not only meets the heat dissipation requirements of the wheel end, but also realizes the recovery and utilization of waste heat.

[0012] Furthermore, the sensing layer includes a non-contact infrared temperature sensor, a contact thermocouple, and a brake pressure sensor. These three sensors work together to ensure the accuracy and reliability of data acquisition. The non-contact infrared temperature sensor is installed on the side of the brake disc and directly measures the real-time temperature of the brake disc friction surface using the infrared temperature measurement principle. Its measurement temperature range covers 0 to 600℃, and the measurement accuracy is controlled within ±5℃, enabling precise capture of temperature changes in the brake disc under different operating conditions. The contact thermocouple is installed on the non-friction surface of the brake disc or on the brake caliper. It is used to verify the measurement data of the non-contact infrared temperature sensor and also serves as a redundant backup device. When the non-contact infrared temperature sensor fails, it can immediately switch to the measurement data of the contact thermocouple to ensure uninterrupted temperature monitoring.

[0013] Furthermore, it includes the following steps: (1) Multi-source information acquisition and fusion: Through various sensors in the perception layer, real-time temperature of each of the four brake discs, brake line pressure, vehicle speed, ambient temperature, actual vehicle load, and road slope are collected simultaneously. The acquisition frequency is dynamically adjusted according to the vehicle's operating conditions to ensure data timeliness. The collected multi-source data is transmitted to the intelligent thermal management controller in the decision layer. Through data preprocessing, outlier removal, and data calibration, the heterogeneous data is fused to form a comprehensive dataset that can accurately reflect the thermal state of the wheel ends. (2) Calculation of braking thermal input power: Based on the fused dataset, according to the preset thermal input power calculation model, combined with braking pressure, braking time, brake disc material and structural parameters, the thermal input power of a single brake disc under the current working conditions is calculated by formula to clarify the heat generation rate during the braking process; (3) Calculation of system heat loss power: Calculate the heat dissipation power of natural convection, forced air cooling (if the active air cooling subsystem is started), and atomization evaporation (if the precision atomization cooling subsystem is started) respectively. The total heat loss power of the system under the current state is obtained by superposition calculation, and the heat dissipation rate is determined. (4) Brake disc temperature prediction update: Based on the law of conservation of energy, the current brake disc temperature is used as a basis, and the calculated heat input power and total heat loss power are combined to predict the brake disc temperature at the next moment through the temperature prediction formula. The prediction time interval is set to 1 to 5 seconds according to the complexity of the working conditions to ensure the timeliness and accuracy of temperature prediction. (5) Cooling strategy decision: The predicted temperature is compared with the preset temperature threshold. Based on the comparison results, a layered and progressive cooling strategy is executed. Different cooling strategies correspond to different heat dissipation intensities and execution logic to ensure a balance between cooling effect and energy consumption. (6) Waste heat recovery and coordinated control: Real-time reception of battery status signals sent by the battery management system (BMS). When the BMS issues a battery heating request and the wheel end brake disc temperature is higher than the preset waste heat recovery threshold, the intelligent thermal management controller sends a control command to the liquid cooling thermal management subsystem to switch the liquid cooling circuit to waste heat recovery mode, and transfer the waste heat generated by braking to the battery coolant to heat the power battery.

[0014] Furthermore, the cooling strategy includes four levels, automatically switching based on the predicted brake disc temperature: Standby / Monitoring Mode: When the predicted brake disc temperature is <150℃, the wheel end thermal state is within a safe range. The system only maintains temperature monitoring and data acquisition functions at the sensing layer, and none of the cooling subsystems at the execution layer are activated to reduce energy consumption; Level 1 Cooling Mode: When 150℃ ≤ predicted brake disc temperature < 300℃, the active air-cooling subsystem at the execution layer is activated. Based on the difference between the predicted temperature and the threshold, the speed of the high-speed centrifugal fan is controlled to increase linearly with temperature. The higher the temperature, the faster the fan speed, and the heat dissipation intensity gradually increases, achieving gentle and efficient heat dissipation; Level 2 Cooling Mode: When 30℃ < 150℃ < 300℃, the system automatically switches between these levels. When the predicted brake disc temperature is between 0℃ and 450℃, the precision fog cooling subsystem is activated while maintaining the operation of the active air cooling subsystem. The piezoelectric ceramic atomizing nozzles begin spraying to cool the brakes. At the same time, a regenerative braking enhancement request is sent to the vehicle controller (VCU) through the interaction layer to reduce the frequency of mechanical braking and reduce heat generation. Overheat protection mode: When the predicted brake disc temperature is ≥450℃, the wheel end is in a high-temperature danger state. The system immediately triggers the audible and visual alarm device to warn the driver. At the same time, a power limiting request is sent to the VCU through the interaction layer to limit the vehicle's power output, reduce the driving speed, reduce the braking frequency, and forcibly reduce the brake disc temperature to avoid brake fade.

[0015] Furthermore, the waste heat recovery and coordinated control also includes a safety arbitration mechanism to ensure that braking safety is prioritized. The intelligent thermal management controller monitors the temperature changes of the wheel-end brake disc in real time. If the brake disc temperature rises rapidly and approaches the trigger threshold of the precision fog cooling subsystem, the safety arbitration logic is immediately activated to prioritize the brake cooling function and dynamically reduce the coolant flow rate of the waste heat recovery circuit. If the temperature continues to rise, the waste heat recovery circuit is completely shut down, and all the heat dissipation capacity of the liquid cooling thermal management subsystem is used for wheel-end cooling. After the brake disc temperature drops to a safe range, the waste heat recovery function is restored according to the battery heating requirements.

[0016] Furthermore, it includes a robust fail-safe strategy to ensure the system maintains basic functions even in fault conditions: when any sensor experiences an abnormal signal or malfunctions, the intelligent thermal management controller retrieves historical operating data, estimates the brake disc temperature based on current operating parameters, and automatically lowers the cooling response threshold, activating the cooling subsystem in advance to prevent temperature runaway; when an actuator (such as a high-speed centrifugal fan or atomizing nozzle) malfunctions, the controller immediately locks the faulty function, locates the fault type through the fault diagnosis module, and attempts to activate other non-faulty actuators for heat dissipation compensation to ensure that basic heat dissipation requirements are met; when communication between the interaction layer and vehicle-related systems is interrupted, the system automatically switches to an independent cooling mode, independently executing cooling strategies based on local data collected by the perception layer, unaffected by external communication, ensuring continuous operation of wheel-end thermal management functions.

[0017] Furthermore, the system and method are applicable to both pure electric trucks and plug-in hybrid electric trucks. In plug-in hybrid electric trucks, when the internal combustion engine starts running, the intelligent thermal management controller receives the internal combustion engine's operating status signal through the interaction layer and automatically switches the operating mode according to the battery temperature and braking conditions: if the braking conditions are complex and the wheel end temperature is high, it switches to the basic mode focused on braking safety cooling to prioritize braking heat dissipation; if the battery temperature is low and the braking conditions are smooth, and the wheel end temperature is within a safe range, it utilizes the waste heat generated by the engine operation to keep the power battery warm through the liquid cooling thermal management subsystem, further improving energy utilization efficiency.

[0018] This invention provides an intelligent thermal management system and control method for the wheel ends of an electrically driven truck, which has the following advantages: 1. This invention achieves precise control of wheel-end temperature by collaboratively collecting data through multiple sensors at the perception layer, combined with intelligent algorithms at the decision layer and layered regulation by three subsystems at the execution layer. Non-contact infrared temperature sensors accurately capture brake disc temperature changes from 0-600℃, while redundant backup with contact thermocouples ensures accurate temperature monitoring. Active air cooling, precise mist cooling, and liquid cooling systems are activated as needed, progressively cooling from gentle heat dissipation to powerful temperature reduction, effectively preventing brake fade. Even under extreme conditions such as long downhill slopes and heavy loads, the brake disc temperature can be stably controlled within a safe range, completely solving the problems of lag and coarse regulation in traditional cooling methods, and significantly improving the braking safety and stability of electric-drive trucks.

[0019] 2. This invention innovatively integrates waste heat recovery functionality. By switching the circuit using a three-way reversing valve in the liquid-cooled thermal management subsystem, the waste heat generated during braking is rationally distributed to the battery coolant, thus maintaining the temperature of the power battery in low-temperature environments. This design not only reduces the ineffective loss of braking waste heat but also lowers the additional energy consumption required for battery heating, alleviating range anxiety for electric-drive trucks. Simultaneously, a safety arbitration mechanism ensures a dynamic balance between braking safety and waste heat recovery. In plug-in hybrid trucks, it can also coordinate with engine waste heat preservation, further optimizing energy utilization efficiency and transforming "heat loss" into "heat gain," aligning with the development trend of energy conservation and emission reduction in new energy vehicles.

[0020] 3. The layered cooling strategy of this invention is deeply integrated with the vehicle system, significantly improving vehicle operating efficiency. In the first-level cooling mode, the fan speed is linearly adjusted with temperature to avoid energy waste; in the second-level cooling mode, the VCU is linked to enhance regenerative braking and reduce reliance on mechanical braking; the overheat protection mode promptly limits power output to reduce safety risks. Seamless switching between modes ensures both effective cooling and avoids excessive energy consumption. Combined with energy replenishment through waste heat recovery, this allows electric-drive trucks to maintain efficient operation even under complex conditions, reducing overall vehicle operating costs, extending driving range, and enhancing the user experience.

[0021] 4. The invention's comprehensive fail-safe strategy and system adaptability significantly improve the product's reliability and applicability. When a sensor fails, temperature is estimated using historical data; when an actuator fails, a compensation mechanism is activated; and when communication is interrupted, an independent cooling mode is switched, comprehensively mitigating the risk of cooling failure due to malfunctions. Simultaneously, the system is compatible with pure electric and plug-in hybrid trucks. In plug-in hybrid models, the system can intelligently switch modes based on the internal combustion engine's operating status, ensuring braking safety while utilizing engine waste heat for thermal insulation. This adapts to the usage needs of different power types of trucks, reducing vehicle adaptation costs and possessing broad application value.

[0022] 5. This invention extends the service life of wheel-end components and reduces vehicle maintenance costs by optimizing the design and control logic of the execution layer components. The intelligent fairing is made of aerospace-grade aluminum alloy, and the atomizing nozzles break water into 5-20 micron droplets. The 3D-printed liquid-cooled heat exchanger efficiently captures heat flow. The component material selection and structural design balance heat dissipation efficiency and durability. Layered cooling avoids damage to brake discs and brake pads caused by sudden temperature rises and falls, reducing tire aging and wheel bearing wear. In addition, the fail-safe strategy reduces abnormal component wear caused by system failures, lowers maintenance frequency and costs, saves users long-term operating costs, and improves the overall cost-effectiveness of the vehicle throughout its life cycle.

[0023] 6. This invention integrates predictive road condition information from in-vehicle navigation to construct an active thermal management mechanism of "early warning - proactive deployment - dynamic control" for the highest-risk condition of long downhill driving for electric-drive trucks. Before the vehicle enters a long downhill section, the system can predict the thermal load based on slope data and vehicle load, and activate advanced cooling strategies in advance. This upgrades brake thermal safety protection from the traditional passive mode of "responding after temperature rises" to an active defense mode of "anticipating challenges and deploying in advance." This innovation significantly improves the thermal safety margin of the braking system under high-risk conditions, effectively avoids safety hazards caused by brake fade during long downhill driving, reduces mechanical brake wear, extends component life, and ultimately greatly enhances the active safety and system durability of electric-drive trucks in complex mountainous road conditions. Attached Figure Description

[0024] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0025] Figure 1 This is a flowchart illustrating the overall architecture of the wheel-end intelligent thermal management system of the present invention. Figure 2 This is a flowchart illustrating the composition of the three subsystems of the execution layer of this invention; Figure 3 This is a flowchart of the data acquisition process for the sensing layer in this invention; Figure 4 This is the main flowchart of the intelligent thermal management control method for wheel ends of the present invention; Figure 5 This is a flowchart illustrating the layered and progressive cooling strategy of the present invention. Detailed Implementation

[0026] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses consistent with some aspects of this disclosure as detailed in the appended claims.

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0028] How to use: After the vehicle is started, the system automatically enters the initialization state. The non-contact infrared temperature sensor, contact thermocouple and brake pressure sensor of the perception layer start up simultaneously to collect data such as the temperature of the four-wheel brake discs and the brake pressure in real time. The interaction layer establishes communication connection with the vehicle controller (VCU), battery management system (BMS) and anti-lock braking system (ABS) through the high-speed CAN bus. The decision layer intelligent thermal management controller begins to receive and integrate multi-source data.

[0029] During operation, the system continuously executes a multi-source information collection and fusion process, simultaneously acquiring data such as vehicle speed, ambient temperature, vehicle load, and road slope. It calculates the braking heat input power and system heat loss power through a preset algorithm, and predicts the brake disc temperature at the next moment based on the law of conservation of energy.

[0030] When the predicted temperature is below 150℃, the system is in standby / monitoring mode, only maintaining data acquisition and temperature monitoring, and does not start the cooling subsystem; when the temperature reaches 150℃ or above but is below 300℃, it automatically switches to the first-level cooling mode, the active air cooling subsystem is started, the speed of the high-speed centrifugal fan increases linearly with the temperature, and the intelligent air deflector dynamically adjusts the air outlet angle according to the vehicle's direction of travel and wind speed to enhance the heat dissipation effect.

[0031] If the temperature continues to rise to 300℃ or above but below 450℃, the system enters the secondary cooling mode, the precision fog cooling subsystem is activated, and the piezoelectric ceramic atomizing nozzle sprays ultra-fine droplets to assist in cooling. At the same time, it requests the VCU to enhance regenerative braking through the interaction layer to reduce the heat generated by mechanical braking. When the temperature reaches 450℃ or above, the overheat protection mode is triggered, the audible and visual alarm device is activated, and a power limiting request is sent to the VCU to reduce the vehicle speed to ensure braking safety.

[0032] When the BMS issues a battery heating request and the wheel end temperature is higher than the waste heat recovery threshold, the system switches the liquid cooling circuit to waste heat recovery mode, captures the braking heat flow through a 3D printed liquid cooling heat exchanger, and distributes it to the battery coolant through a three-way reversing valve; if the wheel end temperature is close to the fog cooling trigger threshold, the safety arbitration mechanism is activated, prioritizing braking cooling and dynamically adjusting or shutting down the waste heat recovery flow.

[0033] In plug-in hybrid electric vehicles, when the internal combustion engine starts, the system automatically switches modes based on braking conditions and battery temperature: when braking conditions are complex, it switches to basic cooling mode to focus on ensuring braking safety; when the battery temperature is low, it uses the engine's waste heat to keep the battery warm.

[0034] If a sensor fails, the system retrieves historical data to estimate the temperature and initiates cooling in advance; if an actuator malfunctions, the faulty function is locked and other actuators are activated for compensation; if communication is interrupted, the system automatically switches to independent cooling mode to ensure continuous operation of the thermal management function. After the vehicle is turned off, the system completes data recording and status reset, shuts down the power to each subsystem, and ends the current thermal management operation. Example:

[0035] Example 1: Implementation Process of Intelligent Thermal Management at the Wheel Ends of Pure Electric Trucks under Frequent Start-Stop Conditions in Urban Delivery After the pure electric truck starts, the wheel-end intelligent thermal management system automatically completes initialization. The non-contact infrared temperature sensor, contact thermocouple and brake pressure sensor of the perception layer are activated simultaneously and begin to continuously collect core data such as the temperature of the four-wheel brake discs and the brake pressure. The interaction layer establishes a stable communication link with the vehicle controller, battery management system and anti-lock braking system through the high-speed CAN bus. The intelligent thermal management controller of the decision layer enters the data receiving and processing state.

[0036] Vehicles enter urban roads to carry out delivery operations, frequently starting and stopping during the journey, and drivers repeatedly operate the brake pedal. The perception layer captures dynamic data such as vehicle speed, ambient temperature, vehicle load, and road gradient in real time, and transmits all multi-source data to the decision-making layer in real time.

[0037] The intelligent thermal management controller integrates the collected data and forms a comprehensive dataset reflecting the thermal state of the wheel end by removing outliers and calibrating data accuracy. Then, it calculates the braking thermal input power and system thermal loss power according to preset logic, and continuously predicts the brake disc temperature at the next moment based on the law of conservation of energy.

[0038] In the initial stage, the braking frequency is low, the brake disc temperature is low, and the predicted temperature is below the standby / monitoring mode threshold. The system only maintains data acquisition and temperature monitoring, and all cooling subsystems are in a dormant state to reduce energy consumption.

[0039] As the delivery process progresses and the braking frequency increases, the brake disc temperature gradually rises. When the predicted temperature reaches the activation condition of the first-level cooling mode, the decision-making layer immediately sends a start command to the active air-cooling subsystem of the execution layer.

[0040] After the active air-cooling subsystem is activated, the high-speed centrifugal fan starts running, and its speed is gradually adjusted according to the temperature change of the brake disc. The electric adjustable guide vanes built into the intelligent air deflector dynamically optimize the air outlet angle according to the vehicle's direction of travel and real-time wind speed, ensuring that the cooling airflow is precisely applied to the core heat-generating area of ​​the brake disc, thereby improving heat dissipation efficiency.

[0041] During subsequent driving, some sections of the road became congested, and braking became more frequent. The brake disc temperature continued to rise, and the predicted temperature reached the trigger standard for the second-level cooling mode. The system then activated the precision fog cooling subsystem.

[0042] A miniature magnetically driven diaphragm pump delivers liquid from a stainless steel reservoir to piezoelectric ceramic atomizing nozzles on each brake. The nozzles atomize the liquid and spray it onto the brake disc surface, where it cools down rapidly through evaporation and heat absorption. Simultaneously, the interaction layer sends a request to the vehicle controller to enhance regenerative braking intensity and reduce the frequency of mechanical braking, thereby reducing heat generation at the source.

[0043] After the delivery task is completed, the frequency of vehicle braking is greatly reduced, and the brake disc temperature gradually decreases. When the predicted temperature is lower than the threshold of the first-level cooling mode, the system shuts down the precision fog cooling subsystem, and the fan speed of the active air cooling subsystem gradually decreases, eventually returning to the standby / monitoring mode until the vehicle is turned off. After the system completes data recording, it shuts down the power to each component.

[0044] Example 2: Implementation Process of Intelligent Thermal Management at Wheel Ends in Low-Temperature Environments During Long-Distance Transportation of Plug-in Hybrid Trucks When a plug-in hybrid electric vehicle starts in a low-temperature environment, after the intelligent thermal management system at the wheel end is initialized, various sensors in the perception layer quickly start up to collect basic data such as brake disc temperature and brake pressure. The interaction layer synchronously establishes communication with relevant systems of the whole vehicle and receives feedback signals on the working status of the internal combustion engine.

[0045] The vehicle initially operates in electric mode, with the brake disc temperature at a low level. The system then enters standby / monitoring mode, where the perception layer continuously monitors various data and the decision-making layer analyzes thermal management parameters in real time to ensure stable wheel-end conditions.

[0046] The battery management system detected that the power battery temperature was too low and could not meet the optimal operating requirements, so it sent a battery heating request to the intelligent thermal management controller. The decision layer, combined with the wheel end temperature data collected by the sensing layer, determined that the wheel end temperature was higher than the waste heat recovery threshold and immediately initiated the waste heat recovery and coordinated control process.

[0047] After receiving the instruction, the liquid-cooled thermal management subsystem switches the three-way reversing valve to the waste heat recovery circuit. The 3D printed liquid-cooled heat exchanger integrated inside the brake drum efficiently captures the heat flow generated during braking and transfers the heat to the battery coolant through the pipeline to heat and keep the power battery warm.

[0048] During long-distance driving, road conditions are complex and changeable, requiring frequent braking and causing the brake disc temperature to gradually rise. When the decision-making level predicts that the brake disc temperature is approaching the trigger threshold of the precision fogging subsystem, the safety arbitration mechanism is activated. The system prioritizes brake cooling, dynamically reducing the coolant flow in the waste heat recovery circuit to prevent heat buildup from affecting braking safety.

[0049] As braking intensity increases, the brake disc's predicted temperature reaches the activation condition for Level 1 cooling mode. The active air-cooling subsystem is activated, the intelligent air guide adjusts the air outlet angle, and the high-speed centrifugal fan adjusts its speed according to temperature changes to enhance the brake disc's heat dissipation effect.

[0050] After driving for a period of time, the vehicle's battery charge becomes insufficient, and the internal combustion engine starts to provide power output. The system receives the internal combustion engine start signal through the interaction layer. Considering the current smooth braking conditions and the fact that the battery temperature still needs to be raised, the system switches the operating mode and uses the waste heat generated by the engine to keep the power battery warm through the liquid cooling thermal management subsystem. At the same time, it keeps the active air cooling subsystem running normally to ensure that the brake disc temperature remains stable within a safe range.

[0051] When the battery management system detects that the battery temperature has risen to a suitable range, it stops sending heating requests, the three-way reversing valve switches back to the heat dissipation circuit, and the waste heat recovery function is turned off.

[0052] During subsequent driving, the system continuously adjusts its working status dynamically based on the predicted temperature of the brake discs. The sensing layer continuously collects data, and the decision-making layer analyzes and calculates in real time to ensure that the wheel-end thermal management is precisely matched with the vehicle's power output and battery insulation requirements, thus guaranteeing the safety and energy efficiency of long-distance transportation.

[0053] Example 3: Implementation Process of Intelligent Thermal Management at the Wheel Ends of a Plug-in Hybrid Truck under Complex Road Condition Switching Situations After the plug-in hybrid truck starts, the wheel-end intelligent thermal management system initializes, the sensing layer sensors start to collect data such as brake disc temperature and brake pressure, the interaction layer establishes communication with the vehicle controller, battery management system and anti-lock braking system, the decision layer enters the data processing state, and at the same time receives the internal combustion engine working status signal.

[0054] The vehicle initially travels on flat urban roads with infrequent braking and low brake disc temperature. The system is in standby / monitoring mode, with the perception layer continuously monitoring data and the decision layer analyzing thermal management parameters in real time.

[0055] The vehicle then entered a hilly section on the outskirts of the city, where the road gradient changed significantly, requiring frequent braking to adjust speed, causing the brake disc temperature to gradually rise. The decision-making team predicted that the temperature had reached the activation conditions for Level 1 cooling mode, triggering the active air-cooling subsystem. The intelligent fairing adjusted the airflow angle based on the road wind speed and the vehicle's direction of travel, while the high-speed centrifugal fan adjusted its speed according to temperature changes to ensure proper brake disc cooling.

[0056] During driving, the battery power is consumed rapidly, and the internal combustion engine starts to provide power. At this time, the braking conditions are more complex, and the brake disc temperature is at a high level. The system automatically switches to the basic mode focused on brake safety cooling, prioritizing brake heat dissipation. The active air cooling subsystem continues to operate efficiently, while the precision fog cooling subsystem is on standby, ready to start at any time.

[0057] After exiting the hilly section, the vehicle entered the highway and maintained a constant speed, significantly reducing braking frequency and causing the brake disc temperature to gradually decrease. The battery management system detected that the battery temperature was too low and sent a heating request. The decision-making layer, based on the wheel end temperature data, determined that the waste heat recovery conditions were met and activated the waste heat recovery function. The three-way reversing valve of the liquid cooling thermal management subsystem switched to the waste heat recovery circuit, using braking waste heat to heat the battery.

[0058] During the later stages of highway driving, a sudden traffic situation necessitates emergency braking, causing the brake disc temperature to rise rapidly. The decision-making system predicts the temperature is approaching the trigger threshold of the precision fog cooling subsystem, initiating a safety arbitration mechanism. The system immediately reduces waste heat recovery flow, prioritizing brake cooling. When the temperature reaches the secondary cooling mode threshold, the precision fog cooling subsystem activates, simultaneously requesting the vehicle controller to enhance regenerative braking to rapidly reduce the brake disc temperature.

[0059] After traffic conditions return to normal, vehicles resume driving at a constant speed, and the brake disc temperature gradually decreases. When the temperature falls below the threshold of the secondary cooling mode, the precision fog cooling subsystem shuts down, and the waste heat recovery function resumes normal flow based on the battery heating requirements.

[0060] As the vehicle approaches its destination, the internal combustion engine shuts off, switching back to electric mode. Based on brake disc temperature and battery status, the system adjusts to standby / monitoring mode, continuously monitoring the wheel wells and battery status until the vehicle is turned off, at which point the system completes data recording and status reset.

[0061] Example 4: Implementation Process of Intelligent Thermal Management at Wheel Ends under Emergency Conditions of Multiple System Component Failures During normal operation of a pure electric truck, the wheel-end intelligent thermal management system is in a stable working state. The sensing layer continuously collects data such as brake disc temperature, brake pressure, and vehicle speed. The decision-making layer calculates thermal power and predicts brake disc temperature according to the process. At this time, the system is in the first-level cooling mode based on the predicted temperature. The active air cooling subsystem is operating normally, the intelligent deflector adjusts the air outlet angle, and the high-speed centrifugal fan provides stable heat dissipation.

[0062] During the journey, the non-contact infrared temperature sensor in the perception layer suddenly showed an abnormal signal. The decision layer discovered through data verification that the sensor had failed, and the fail-safe strategy was immediately activated.

[0063] The intelligent thermal management controller quickly retrieves historical operating data and combines it with operating parameters such as current vehicle speed, braking pressure, and vehicle load to accurately estimate the real-time temperature of the brake disc. At the same time, it automatically lowers the cooling response threshold and prepares for cooling in advance to avoid untimely heat dissipation due to inaccurate temperature monitoring.

[0064] Based on the estimated temperature data, the controller determines that the brake disc temperature still needs to be continuously cooled, and because the cooling response threshold has decreased, it continues to maintain the operating intensity of the active air cooling subsystem to ensure that the brake disc temperature does not exceed the standard.

[0065] Shortly afterward, the high-speed centrifugal fan of the active air-cooling subsystem malfunctioned and could not operate normally. After detecting the actuator failure, the controller immediately locked the faulty function, located the fault type through the fault diagnosis module, and activated the actuator compensation mechanism to attempt to use other non-faulty actuators to meet the heat dissipation requirements.

[0066] Due to the failure of the active air cooling system caused by the fan malfunction, the controller re-estimated the brake disc temperature and found that the temperature was rising rapidly and had reached the conditions for activating the secondary cooling mode. It then activated the precision mist cooling subsystem, in which piezoelectric ceramic atomizing nozzles sprayed droplets to evaporate and absorb heat, thus making up for the failure of the active air cooling subsystem and ensuring the heat dissipation effect of the brake disc.

[0067] When the vehicle travels to a remote section of road, external signal interference causes a temporary interruption in communication between the interaction layer and the vehicle controller. Upon detecting the communication interruption, the system immediately switches to an independent cooling mode, no longer relying on external communication signals. Instead, it independently controls the operation of the precision fog cooling subsystem based solely on data collected locally by the perception layer and internal preset algorithms, continuously maintaining stable brake disc temperatures.

[0068] After a period of time, communication returned to normal, the system automatically switched back to normal working mode, the interaction layer re-established communication with the relevant systems of the vehicle, and the controller, in conjunction with feedback information from the external system, adjusted the cooling strategy and appropriately reduced the operating intensity of the precision fog cooling subsystem.

[0069] After the vehicle arrives at its destination, the driver turns off the vehicle's power. The system records the time, type, and handling process of the fault, which will facilitate subsequent maintenance personnel to troubleshoot and repair. At the same time, the system resets the status to prepare for the next startup.

[0070] Example 5: Predictive Downhill Thermal Management When heavy-duty electric-drive trucks perform long-distance downhill transportation tasks in mountainous areas, this system can significantly improve driving safety by relying on a predictive downhill thermal management strategy.

[0071] When the vehicle reaches a mountainous section of road, the onboard navigation system anticipates an upcoming 12km long downhill section with an average gradient of 6%. This information is simultaneously transmitted to the intelligent thermal management controller via the CAN bus. The decision-making layer immediately triggers the predictive downhill thermal management process, accurately calculating, based on data such as the vehicle's current load of 45t and real-time speed of 60km / h, that the peak thermal input power of the brake discs under long downhill conditions will reach 120kW.

[0072] Based on this prediction, the system activates the active air-cooling subsystem 1 km before entering the downhill section. The high-speed centrifugal fan pre-runs at 80% of its rated power, and the intelligent air deflector is adjusted to the optimal air outlet angle, pre-cooling the brake disc temperature by 15°C to establish a safe thermal margin. Simultaneously, the three-way reversing valve of the liquid-cooled thermal management subsystem switches to the heat dissipation priority mode in advance to maximize the radiator's heat dissipation efficiency.

[0073] Upon entering a long downhill section, the sensing layer continuously collects data on brake disc temperature and brake pressure. When the brake disc temperature rises to 280°C, the system triggers the secondary cooling mode in advance. The piezoelectric ceramic atomizing nozzle of the precision fog cooling subsystem sprays 10μm droplets at a frequency of 5Hz, forming a uniform water film on the surface of the brake disc, which carries away a large amount of heat through evaporation.

[0074] During this process, the system continuously sends requests to the VCU through the interaction layer to enhance regenerative braking intensity and reduce the frequency of mechanical braking intervention by 30%, effectively reducing braking heat input. When the vehicle reaches the middle of the downhill section, the brake disc temperature is stably maintained at around 320℃, far below the overheat protection threshold of 450℃. No audible or visual alarms or power limiting are triggered throughout the entire process, ensuring driving safety on long downhill sections.

[0075] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wheel-end intelligent thermal management system for an electrically driven truck, characterized in that, It includes a perception layer, a decision-making layer, an execution layer, and an interaction layer; the perception layer is used to collect data such as wheel end temperature, braking pressure, and tire temperature; the decision-making layer is an intelligent thermal management controller used to fuse multi-source information and execute control algorithms; the execution layer includes an active air cooling subsystem, a precision fog cooling subsystem, and a liquid cooling thermal management subsystem; the interaction layer communicates with the vehicle control unit (VCU), battery management system (BMS), and anti-lock braking system (ABS) via a high-speed CAN bus.

2. The wheel-end intelligent thermal management system according to claim 1, characterized in that, The active air-cooling subsystem includes a high-speed centrifugal fan and an intelligent air deflector; the rated power of the high-speed centrifugal fan is 150W to 250W, and the maximum air volume is not less than 30m³ / min; the intelligent air deflector is made of aviation aluminum alloy and has built-in electrically adjustable air deflectors, which can adjust the air outlet angle according to the vehicle's direction of travel and wind speed.

3. The wheel-end intelligent thermal management system according to claim 1, characterized in that, The precision fog cooling subsystem includes piezoelectric ceramic atomizing nozzles, a stainless steel liquid storage tank, and a miniature magnetically driven diaphragm pump; each actuator is equipped with 2 to 4 atomizing nozzles, which can break water into droplets of 5 to 20 micrometers; the liquid storage tank has a volume of 8 to 12L, a built-in liquid level sensor and an electric heater, and has antifreeze function.

4. The wheel-end intelligent thermal management system according to claim 1, characterized in that, The liquid-cooled thermal management subsystem includes a 3D-printed liquid-cooled heat exchanger, a plate heat exchanger, and a three-way reversing valve. The 3D-printed liquid-cooled heat exchanger is integrated inside the brake drum to capture braking heat flow. The three-way reversing valve can switch between the heat dissipation circuit and the waste heat recovery circuit to realize the distribution of heat between the radiator and the battery coolant.

5. The wheel-end intelligent thermal management system according to claim 1, characterized in that, The sensing layer includes a non-contact infrared temperature sensor, a contact thermocouple, and a brake pressure sensor; the non-contact infrared temperature sensor is used to measure the temperature of the brake disc friction surface, ranging from 0 to 600°C, with an accuracy of ±5°C; the contact thermocouple is used for calibration and redundancy backup.

6. A wheel-end intelligent thermal management control method for an electrically driven truck, characterized in that, Includes the following steps: (1) Multi-source information collection and fusion: Collect data such as four-wheel brake disc temperature, brake pressure, vehicle speed, ambient temperature, vehicle load, and road slope; (2) Calculation of braking thermal input power: According to the formula Calculate the thermal input power of a single brake disc; (3) Calculation of system heat loss power: Calculate the total heat loss power of natural convection heat dissipation, forced air cooling heat dissipation, and atomized evaporation heat dissipation. ; (4) Brake disc temperature prediction update: Based on the law of conservation of energy, through the formula Predict the brake disc temperature at the next moment; (5) Cooling strategy decision: Compare the predicted temperature with the preset threshold and execute a layered cooling strategy; (6) Waste heat recovery and coordinated control: When the BMS issues a battery heating request and the wheel end temperature is higher than the recyclable threshold, switch the liquid cooling circuit to waste heat recovery mode.

7. The control method according to claim 6, characterized in that, The cooling strategy includes: Standby / Monitoring Mode: When the predicted temperature is <150℃, only the temperature is monitored; Level 1 cooling mode: When 150℃≤predicted temperature<300℃, the active air cooling subsystem is activated, and the speed increases linearly with the temperature; Secondary cooling mode: When the temperature is between 300℃ and the predicted temperature and 450℃, the precision fog cooling subsystem is activated and the VCU is requested to enhance regenerative braking. Overheat protection mode: When the predicted temperature is ≥450℃, an audible and visual alarm is triggered, and the VCU is requested to limit the vehicle's power output.

8. The control method according to claim 6, characterized in that, The waste heat recovery and coordinated control also includes a safety arbitration mechanism: if the wheel end temperature is close to the fog cooling trigger threshold, brake cooling will be prioritized, and the waste heat recovery flow will be dynamically reduced or shut off.

9. The control method according to claim 6, characterized in that, It also includes fail-safe strategies: when a sensor fails, it uses historical data to estimate the temperature and lowers the cooling response threshold; when an actuator fails, it locks the faulty function and tries to compensate with other actuators; when communication is interrupted, it switches to an independent cooling mode.

10. The intelligent thermal management system for wheel ends according to claim 1 or the control method according to claim 6, characterized in that, The system and method are applicable to pure electric trucks and plug-in hybrid trucks; in plug-in hybrid trucks, when the internal combustion engine starts, the system automatically switches to a basic mode focused on brake safety cooling, or uses the engine's waste heat to help keep the battery warm.

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