Integrated thermal management method and system for a pure electric commercial vehicle

Abstract

The application discloses an integrated thermal management method and system of a pure electric commercial vehicle, relates to the technical field of new energy vehicle thermal management, and comprises the following steps: collecting real-time operation state parameters and obtaining a historical operation state parameter sequence; inputting a model predictive control engine and outputting predicted thermal load demands of each thermal management loop in a future preset time period; determining a target operation mode; taking the optimal configuration parameters corresponding to the target operation mode as constraint conditions, taking the minimization of total thermal management energy consumption, the minimization of the deviation of the battery temperature from a preset battery temperature interval, and the minimization of the deviation of the vehicle temperature from a preset comfortable temperature interval as optimization objectives, constructing a multi-objective optimization function and solving the function, obtaining optimal control amounts of each actuator, and delivering the optimal control amounts to a bottom-layer PID controller to output driving signals to corresponding actuators. Through multi-loop integrated coupling, waste heat recovery, and model predictive control, efficient collaborative thermal management under all working conditions is realized, and energy efficiency and cruising range are improved.

Description

Technical Field

[0001] This application relates to the field of thermal management technology for new energy vehicles, specifically to an integrated thermal management method and system for pure electric commercial vehicles. Background Technology

[0002] Under long-range, high-load conditions, pure electric commercial vehicles generate a significant amount of heat in their power batteries, drive motors, and electronic control systems. If heat dissipation is insufficient, batteries are prone to overheating-induced degradation, shortened lifespan, and even thermal runaway. Motors and electronic controls may reduce power output due to overheating, affecting the vehicle's overall performance and safety. Simultaneously, the cooling / heating demands of the passenger compartment further increase the load on the vehicle's thermal management system. To ensure passenger comfort and environmental adaptability, higher requirements are placed on the thermal management of pure electric commercial vehicles.

[0003] Currently, pure electric commercial vehicles generally adopt a distributed or semi-integrated thermal management architecture, in which the battery cooling / heating circuit, the motor and electronic control cooling circuit, and the passenger compartment air conditioning system operate relatively independently, lacking deep coupling. This architecture has obvious drawbacks: First, the circuits cannot coordinate the allocation of heating and cooling resources, and each circuit has its own pumps, valves, radiators, and other components, resulting in complex piping and high energy consumption. Second, due to insufficient circuit coupling depth and complex heat exchange paths, the generated waste heat is difficult to fully utilize, resulting in serious energy waste. Third, in the wide temperature range of all operating conditions, the existing thermal management architecture often uses a single threshold or PID control strategy, which is difficult to respond quickly to dynamic changes in multiple heat sources, and is prone to problems such as improper allocation of heating and cooling resources, overcooling or overheating, and significant reduction in driving range. Summary of the Invention

[0004] To address the aforementioned issues, this application proposes an integrated thermal management method for pure electric commercial vehicles, applicable to a thermal management control unit in pure electric commercial vehicles, comprising: The system collects real-time operating status parameters of the pure electric commercial vehicle during the current management cycle and obtains historical operating status parameter sequences for historical management cycles. The real-time operating status parameters and the historical operating status parameter sequence are input into the model predictive control engine, which outputs the predicted heat load demand for each thermal management loop within a future preset time period; the thermal management loop includes a refrigeration loop, a battery loop, and a motor loop. The target operating mode of the pure electric commercial vehicle is determined based on the real-time operating status parameters and the predicted heat load demand. Using the optimized configuration parameters corresponding to the target operating mode as constraints, and taking the minimization of the total thermal management energy consumption of the pure electric commercial vehicle, the minimization of the first deviation between the battery temperature and the preset battery temperature range, and the minimization of the second deviation between the actual temperature inside the vehicle and the preset comfort temperature range as optimization objectives, a multi-objective optimization function is constructed. The model predictive control engine solves the multi-objective optimization function to obtain the optimal control quantity for each actuator, and sends it to the corresponding underlying PID controller to output drive signals to the corresponding actuators so that the temperature of each thermal management loop approaches the corresponding target temperature.

[0005] On the other hand, this application also provides an integrated thermal management system for pure electric commercial vehicles, applicable to pure electric commercial vehicles, including: The refrigeration circuit includes a compressor, a water-cooled condenser, an evaporator, and an electronic expansion valve. The first refrigerant outlet of the water-cooled condenser is connected to the second refrigerant inlet of the evaporator and the third refrigerant inlet of the battery cooler. The second refrigerant outlet and the third refrigerant outlet are both connected to the fourth refrigerant inlet of the compressor. The battery thermal management circuit includes a battery water-cooling plate, a first water pump, a PTC heater, a first radiator, and the battery cooler. The battery water-cooling plate, the PTC heater, the first radiator, and the battery cooler are connected by a multi-way valve to form a battery cooling branch and a battery heating branch. The motor thermal management circuit includes a motor water jacket, an electronic control cooling plate, a second water pump, and a second radiator. The motor water jacket, the electronic control cooling plate, and the second radiator are connected by a multi-way valve. The motor thermal management circuit is selectively connected to the battery cooler through the multi-way valve to transfer the motor's waste heat to the cooling circuit. The control unit is connected to the compressor, each of the electronic expansion valves, each of the water pumps, the PTC heater, and each of the multi-way valves, and is configured to perform an integrated thermal management method for a pure electric commercial vehicle as described in the above example.

[0006] The integrated thermal management method for pure electric commercial vehicles proposed in this application can bring the following beneficial effects: By deeply coupling the cooling circuit, battery thermal management circuit, and motor thermal management circuit, and setting up a waste heat recovery branch, unified allocation and cross-circuit reuse of the vehicle's thermal resources are achieved. Compared to the traditional distributed architecture where the battery, motor, and air conditioning circuits operate independently, this application can transfer the waste heat generated by the motor operation to the battery and passenger compartment for heating through the cooling circuit. This significantly reduces the dependence on and usage time of the PTC electric heater, effectively reduces the vehicle's power consumption under low-temperature conditions, improves range and energy efficiency, and simplifies the pipeline layout through circuit integration, reducing overall vehicle cost and failure rate.

[0007] Furthermore, this application employs a model predictive control engine to predict future heat load demands and combines a multi-objective optimization method to dynamically allocate cooling / heating resources among various actuators, thereby minimizing the total energy consumption of vehicle thermal management while meeting the optimal operating temperature range of the battery and the comfort requirements of the passenger compartment. Attached Figure Description

[0008] 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: Figure 1 This is a schematic diagram of the overall structure of the integrated thermal management system for a pure electric commercial vehicle in this application embodiment; Figure 2 This is a schematic diagram of the operating principle of each circuit of the thermal management system in the heating mode in the embodiments of this application; Figure 3 This is a schematic diagram of the operation principle of each loop of the thermal management system under the low cooling demand mode in the embodiments of this application; Figure 4 This is a schematic diagram of the operating principle of each loop of the thermal management system under the cooling demand mode in the embodiments of this application; Figure 5 This is a schematic diagram of the operating principle of each loop of the thermal management system under high cooling demand mode in the embodiments of this application; Figure 6 This is a flowchart illustrating an integrated thermal management method for a pure electric commercial vehicle according to an embodiment of this application. Detailed Implementation

[0009] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0010] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0011] like Figure 1As shown in the figure, this application provides an integrated thermal management system for a pure electric commercial vehicle, comprising four parts: a cooling circuit, a battery thermal management circuit, a motor thermal management circuit, and a control unit. The cooling circuit provides active cooling for the passenger compartment and battery; the battery thermal management circuit cools or heats the battery; the motor thermal management circuit dissipates heat from the motor and electronic control system, and can selectively recover waste heat from the motor to the cooling circuit; the control unit performs coordinated management of the various circuits.

[0012] The refrigeration circuit includes a compressor 1, a water-cooled condenser 2, an evaporator 3, a battery cooler 4, a first electronic expansion valve 17, and a second electronic expansion valve 18.

[0013] In the refrigeration circuit, the refrigerant outlet of compressor 1 is connected to the refrigerant inlet of water-cooled condenser 2; the refrigerant outlet of water-cooled condenser 2 is divided into two paths: one path connects to the refrigerant inlet of evaporator 3 via a first electronic expansion valve 17, and the other path connects to the refrigerant inlet of battery cooler 4 via a second electronic expansion valve 18; the refrigerant outlets of evaporator 3 and battery cooler 4 merge and connect to the refrigerant inlet of compressor 1, forming a refrigerant circulation loop. Evaporator 3 is located in the passenger compartment to provide cooling; battery cooler 4 facilitates heat exchange between the refrigerant and coolant, providing cooling for the battery or recovering waste heat from the motor. Preferably, the refrigeration circuit uses environmentally friendly refrigerant R134a or R1234yf.

[0014] The battery thermal management circuit includes a battery water-cooling plate 5, a first water pump 6, a PTC heater 7, a first radiator 8, a battery cooler 4, a first multi-way valve 13, a second multi-way valve 14, a third multi-way valve 15, and a fourth multi-way valve 16. The battery water-cooling plate 5 is installed inside the power battery pack and is used for heat exchange with the individual battery cells.

[0015] Specifically, the coolant outlet of the battery water-cooling plate 5 is connected to the first port of the first multi-way valve 13, the second port of the first multi-way valve 13 is connected to the inlet of the PTC heater 7, the third port of the first multi-way valve 13 is connected to the inlet of the first radiator 8, and the fourth port of the first multi-way valve 13 is connected to the first port of the second multi-way valve 14. The outlet of the PTC heater 7 is connected to the coolant inlet of the battery cooler 4; the coolant outlet of the battery cooler 4 is connected to the first port of the third multi-way valve 15; the second port of the third multi-way valve 15 is connected to the inlet of the battery water-cooling plate 5; and the third port of the third multi-way valve 15 is connected to the first port of the fourth multi-way valve 16. The outlet of the first radiator 8 is connected to the second port of the fourth multi-way valve 16; the third port of the fourth multi-way valve 16 is connected to the inlet of the first water pump 6; and the outlet of the first water pump 6 is connected to the inlet of the battery water-cooling plate 5. Through the above connections, the battery thermal management circuit can form a battery cooling branch and a battery heating branch respectively.

[0016] The motor thermal management circuit includes a motor water jacket 11, an electronic control cooling plate 12, a second water pump 9, a second radiator 10, and a second multi-way valve 14. The motor water jacket 11 is fitted outside the drive motor to absorb the heat generated by the motor operation; the electronic control cooling plate 12 is located below the motor controller to dissipate heat from the electronic control system.

[0017] Specifically, the outlet of the motor water jacket 11 is connected to the second port of the second multi-way valve 14; the third port of the second multi-way valve 14 is connected to the inlet of the second radiator 10; the outlet of the second radiator 10 is connected to the inlet of the second water pump 9; and the outlet of the second water pump 9 is connected to the inlet of the motor water jacket 11, forming a motor coolant circulation loop. The first port of the second multi-way valve 14 is connected to the coolant inlet of the battery cooler 4. By switching the ports of the second multi-way valve 14, the motor thermal management loop can be selectively connected to the battery cooler 4 to transfer the motor's waste heat to the refrigeration loop. The coolant side of the water-cooled condenser 2 can be selectively connected in series to the motor thermal management loop or the battery thermal management loop through pipelines. The specific connection method is controlled by the switching of each multi-way valve according to the operating mode.

[0018] Figures 2 to 5 The connection status of each loop in this application under different operating modes is shown respectively. Figure 2 This is a schematic diagram illustrating the operating principle of each circuit in the thermal management system during heating mode. Figure 3 This is a schematic diagram illustrating the operating principle of each loop in the thermal management system under low cooling demand mode. Figure 4 This is a schematic diagram illustrating the operating principle of each loop in the thermal management system under medium cooling demand mode. Figure 5 This is a schematic diagram illustrating the operating principle of each loop in the thermal management system under high cooling demand mode. It should be noted that... Figures 2 to 5 The solid arrows in the diagram indicate the actual flow path of the coolant or refrigerant in this mode, the dashed lines indicate the pipes that are disconnected in this mode, and the thickened pipes indicate the main circuits involved in heat exchange in this mode.

[0019] In addition, the control unit is connected to the compressor 1, the first electronic expansion valve 17, the second electronic expansion valve 18, the first water pump 6, the second water pump 9, the PTC heater 7, the first multi-way valve 13, the second multi-way valve 14, the third multi-way valve 15, and the fourth multi-way valve 16 via a CAN bus for collecting detection signals from each sensor and sending control commands to each actuator. Preferably, the control unit is based on the AUTOSAR architecture with a sampling period of 100ms, and can adjust the compressor speed, the flow rate of each water pump, the opening degree of each electronic expansion valve, the power of the PTC heater, and the port connectivity status of each multi-way valve in real time.

[0020] like Figure 2As shown, when the ambient temperature outside the vehicle is within the preset heating temperature range, the battery requires preheating, and the motor is running, the system enters the waste heat recovery heating mode.

[0021] In waste heat recovery heating mode, only the second electronic expansion valve 18 is open in the air conditioning circuit, and branch 2, which connects to the battery cooler 4 via the second electronic expansion valve 18, is operational. When compressor 1 starts, the refrigerant is compressed by compressor 1 and enters the water-cooled condenser 2. After releasing heat and condensing in the water-cooled condenser 2, it is throttled by the second electronic expansion valve 18 and enters the battery cooler 4. In the battery cooler 4, it absorbs heat from the coolant and then returns to compressor 1, completing the refrigerant cycle. During this process, the battery cooler 4 acts as an evaporator, absorbing heat from the coolant.

[0022] In the water pump 2 circuit, i.e. the waste heat recovery branch, the second water pump 9 starts, and the coolant flows through the motor water jacket 11 to absorb the waste heat generated by the motor operation. It then flows through the second multi-way valve 14 to the coolant side of the battery cooler 4, where the heat is transferred to the refrigeration circuit, completing the waste heat recovery cycle.

[0023] In the water pump 1 circuit, i.e., the battery and passenger compartment heating circuit, the first water pump 6 is started. The coolant flows sequentially through the first multi-way valve 13, the PTC heater 7, and the coolant outlet of the battery cooler 4. In this mode, the battery cooler 4 also functions as a heat exchanger. After absorbing the heat released by the refrigerant on the coolant side of the water-cooled condenser 2, it flows through the third multi-way valve 15 to the battery water-cooling plate 5 to heat the battery, or provides heat to the passenger compartment through the heater core. When the ambient temperature outside the vehicle is lower than the preset auxiliary heating threshold, the PTC heater 7 is started to provide auxiliary heating and preheat the battery to above 15°C.

[0024] In the waste heat recovery heating mode, the first multi-way valve 13 connects its first port and the second port, the second multi-way valve 14 connects its first port and the second port, the third multi-way valve 15 connects its first port and the second port, and the fourth multi-way valve 16 is disconnected; the fans of the first radiator 8 and the second radiator 10 do not start.

[0025] like Figure 3 As shown, when only the battery requires cooling, the passenger compartment has no cooling request, and the overall vehicle heat load is low, the system enters a low cooling demand mode. In this mode, the air conditioning circuit does not work, and compressor 1 is turned off.

[0026] In the water pump 2 circuit, the second water pump 9 starts, and the coolant flows through the motor water jacket 11 to absorb the heat of the motor. It then flows through the second multi-way valve 14 to the second radiator 10, where the heat is discharged to the environment. After passing through the second radiator 10, the coolant returns to the second water pump 9, completing the heat dissipation cycle of the motor circuit.

[0027] In the water pump 1 circuit, the first water pump 6 starts, and the coolant flows through the battery water cooling plate 5 to absorb the battery heat. It then flows through the first multi-way valve 13 and the second multi-way valve 14 to the coolant side of the battery cooler 4, where it is cooled by the refrigerant. After passing through the third multi-way valve 15 and the fourth multi-way valve 16, it flows to the first radiator 8 to discharge some of the remaining heat to the environment. Finally, it returns to the first water pump 6, completing the battery circuit cooling cycle.

[0028] In the low cooling demand mode, the first multi-way valve 13 connects its first port and third port, the second multi-way valve 14 connects its second port and third port, the third multi-way valve 15 connects its second port and third port, and the fourth multi-way valve 16 connects its first port and second port; the fans of the first radiator 8 and the second radiator 10 are selectively activated according to the cooling demand.

[0029] like Figure 4 As shown, when both the passenger compartment and the battery have cooling needs and the outside temperature is within the preset medium temperature range, the system enters the medium cooling demand mode.

[0030] In medium-cooling demand mode, both the first electronic expansion valve 17 and the second electronic expansion valve 18 in the air conditioning circuit are open, and branch 1 containing evaporator 3 and branch 2 containing battery cooler 4 operate simultaneously. Compressor 1 starts, and the refrigerant is compressed by compressor 1 and then enters the water-cooled condenser 2 for condensation. It is then divided into two paths: one path enters evaporator 3 through the first electronic expansion valve 17 to provide cooling for the passenger compartment, and the other path enters battery cooler 4 through the second electronic expansion valve 18 to provide cooling for the battery; after evaporation, the two refrigerant paths merge and return to compressor 1.

[0031] In the water pump 2 circuit, the second water pump 9 starts, and the coolant flows through the motor water jacket 11 to absorb the heat of the motor. After passing through the second multi-way valve 14 and the second radiator 10, the heat is discharged to the environment and then returns to the second water pump 9.

[0032] In the water pump 1 circuit, the first water pump 6 starts, and the coolant flows sequentially through the battery water-cooling plate 5 to absorb battery heat. It then flows through the first multi-way valve 13 and the second multi-way valve 14 to the coolant side of the battery cooler 4, where it is cooled by the refrigerant. Afterward, it flows through the third multi-way valve 15 and the fourth multi-way valve 16 to the first radiator 8 to dissipate some of the remaining heat to the environment, and finally returns to the first water pump 6, completing the battery circuit cooling cycle. Simultaneously, the coolant side of the water-cooled condenser 2 is connected to the battery thermal management circuit, and the first radiator 8 removes the heat released by the condensation of the refrigerant in the water-cooled condenser 2. In this mode, the radiator 1 dissipates heat for both the water-cooled condenser 2 and the battery circuit.

[0033] In the medium cooling demand mode, the first multi-way valve 13 connects its first port and fourth port, the second multi-way valve 14 connects its second port and third port, the third multi-way valve 15 connects its first port and third port, and the fourth multi-way valve 16 connects its first port and second port; the speed of compressor 1 is dynamically adjusted by the control unit according to the heat load.

[0034] like Figure 5 As shown, when both the passenger compartment and the battery have cooling needs and the outside temperature is higher than the preset high temperature threshold, the system enters the high cooling demand mode.

[0035] In high cooling demand mode, both the first electronic expansion valve 17 and the second electronic expansion valve 18 in the air conditioning circuit are open, and branch circuit 1 and branch circuit 2 work simultaneously. Compressor 1 starts and runs at a speed higher than that in medium cooling demand mode. After being compressed by compressor 1, the refrigerant enters the water-cooled condenser 2 for condensation, and then splits into two paths, entering the evaporator 3 and the battery cooler 4 respectively. After evaporation, the refrigerant merges and returns to compressor 1.

[0036] In the water pump 2 circuit, the second water pump 9 starts, and the coolant flows through the motor water jacket 11 to absorb the heat of the motor. It then flows through the second multi-way valve 14 to the coolant side of the water-cooled condenser 2 to absorb the heat released by the refrigerant condensation in the water-cooled condenser 2. Finally, it passes through the second radiator 10 to discharge the residual heat of the motor and the heat of the water-cooled condenser 2 to the environment, and finally returns to the second water pump 9.

[0037] In the water pump 1 circuit, the first water pump 6 starts, and the coolant flows sequentially through the battery water-cooling plate 5 to absorb battery heat. It then flows through the first multi-way valve 13 and the second multi-way valve 14 to the coolant side of the battery cooler 4, where it is cooled by the refrigerant. Finally, it flows through the third multi-way valve 15 and the fourth multi-way valve 16 to the first radiator 8 to dissipate some of the remaining heat to the environment, and finally returns to the first water pump 6, completing the battery circuit cooling cycle. In this mode, the coolant side of the water-cooled condenser 2 is not connected to the battery thermal management circuit, but rather to the motor thermal management circuit. The second radiator 10 simultaneously dissipates heat from the water-cooled condenser 2, the motor, and the electronic control cooling plate 12, enabling on-demand allocation of heat dissipation resources.

[0038] In the high cooling demand mode, the first multi-way valve 13 connects its first port to its fourth port, the second multi-way valve 14 connects its first port to its third port, the third multi-way valve 15 connects its first port to its third port, and the fourth multi-way valve 16 connects its first port to its second port; the compressor 1 speed is increased to increase the cooling capacity, and the fan of the second radiator 10 runs at a high speed to enhance the heat dissipation capacity.

[0039] like Figure 6 As shown in the figure, this application provides an integrated thermal management method for a pure electric commercial vehicle, including: S101. Collect the real-time operating status parameters of the pure electric commercial vehicle in the current management cycle, and obtain the historical operating status parameter sequence of the historical management cycle.

[0040] Specifically, at the beginning of each management cycle, the control unit collects real-time detection values ​​of various operating status parameters from the external temperature sensor, battery management system, motor controller, air conditioning controller, and refrigeration system pressure sensor, and simultaneously reads the historical operating status parameter sequence stored in the internal memory for previous management cycles. These operating status parameters characterize the vehicle's current thermal state and load requirements.

[0041] The operating status parameters include external environmental parameters, battery status parameters, motor status parameters, passenger compartment status parameters, and refrigeration system status parameters. Specifically, external environmental parameters include external ambient temperature and humidity, collected by temperature and humidity sensors located at the front of the vehicle; battery status parameters include average battery temperature, battery inlet temperature, battery outlet temperature, and real-time battery charge / discharge load, collected by the battery management system through individual battery cell temperature and current sensors and forwarded to the control unit; motor status parameters include motor winding temperature, motor controller temperature, and motor output load torque or power, collected by the motor controller and forwarded to the control unit; passenger compartment status parameters include the passenger compartment set temperature and the actual temperature inside the passenger compartment. The passenger compartment set temperature is set by the user through the air conditioning control panel and sent to the control unit, while the actual temperature inside the passenger compartment is collected by temperature sensors located inside the passenger compartment; refrigeration system status parameters include evaporator outlet temperature, system high-pressure side refrigerant pressure, and system low-pressure side refrigerant pressure, collected by pressure and temperature sensors located at the evaporator outlet, compressor outlet, and compressor inlet, respectively.

[0042] The historical operating status parameter sequence is a sequence composed of operating status parameters collected within N consecutive historical management cycles prior to the current management cycle. The value of N ensures that the historical operating status parameter sequence covers a preset historical duration. Specifically, the historical operating status parameter sequence includes: battery heat generation time series, i.e., the trajectory of battery temperature change over a historical period; motor waste heat time series, i.e., the trajectory of motor temperature change over a historical period; vehicle driving conditions, i.e., the trajectory of vehicle speed, gradient, and load change over a historical period; and air conditioning historical adjustment records, i.e., the historical opening / speed change trajectory of the compressor and electronic expansion valve.

[0043] S102. Input the real-time operating status parameters and the historical operating status parameter sequence into the model predictive control engine, and output the predicted heat load demand corresponding to each thermal management loop in the future preset time period; the thermal management loop includes a refrigeration loop, a battery loop and a motor loop.

[0044] Specifically, the control unit inputs real-time operating status parameters and acquired historical operating status parameter sequences into the model predictive control engine. The model predictive control engine identifies the temperature rise lag characteristics of each thermal management loop based on the temperature change trajectory and load change trajectory of each thermal management loop in the historical operating status parameter sequence. Combined with the current temperature value and current load value of each thermal management loop at the current moment, it predicts the predicted temperature value of each thermal management loop in the future preset time period. Then, based on the difference between the predicted temperature value and the corresponding target temperature value, it determines the predicted heat load demand of each thermal management loop.

[0045] The predicted heat load demand is used to characterize the amount of heat removal or cooling supply required by each thermal management loop within a preset future time period.

[0046] In practical implementation, the control unit first extracts the temporal features from the historical operating status parameter sequence. From the historical operating status parameter sequence, the temperature change trajectory and load change trajectory of each thermal management loop within a preset historical time period are extracted to construct the temporal status features.

[0047] The temperature change trajectory includes battery temperature time-series data for the battery circuit within a preset historical time period, motor temperature time-series data for the motor circuit within a preset historical time period, and passenger compartment temperature time-series data for the passenger compartment circuit within a preset historical time period; the load change trajectory includes real-time battery charging and discharging load time-series data for the battery circuit within a preset historical time period, motor output load torque or power time-series data for the motor circuit within a preset historical time period, and evaporator outlet temperature time-series data for the refrigeration circuit within a preset historical time period.

[0048] It should be noted that the above time series data reflects the thermal state change pattern of each thermal management loop over a period of time, and can be used to identify the temperature rise lag characteristics of each loop.

[0049] Simultaneously, the control unit extracts the current temperature and load values ​​of each thermal management circuit from the real-time operating status parameters to construct the current state characteristics. The current temperature values ​​include the average battery temperature of the battery circuit, the motor winding temperature of the motor circuit, and the actual temperature inside the passenger compartment of the passenger compartment. The current load values ​​include the real-time battery charge / discharge load of the battery circuit, the motor output load torque or power of the motor circuit, and the refrigerant pressure on the high-pressure side of the system in the refrigeration circuit.

[0050] The timing state features and current state features are input into the Model Predictive Control Engine (MPC Engine). Based on the temperature change trajectory and load change trajectory of each thermal management loop in the timing state features, the MPC Engine identifies the temperature change lag time constant of each thermal management loop.

[0051] It should be noted that the lag time constant reflects the degree of delay in the response of the thermal management loop to thermal excitation and is a key parameter that determines the future temperature change trend. Specifically, the identification method is as follows: the model predictive control engine performs a time-series correlation analysis between the historical temperature change trajectory and the historical load change trajectory in the time-series state characteristics. By fitting the delay time of the temperature change relative to the load change, the lag time constant of each thermal management loop is obtained.

[0052] The model predictive control engine calculates the predicted temperature value of each thermal management circuit at each moment within a preset future time period based on the current state characteristics and the identified hysteresis time constant. Specifically, using the current temperature value in the current state characteristics as the initial prediction condition and the current load value in the current state characteristics as the thermal excitation input at the current moment, and combining the response delay characteristics represented by the hysteresis time constant, the engine recursively calculates the temperature changes at each moment within the preset future time period to obtain the predicted temperature values ​​of the battery circuit, the motor circuit, and the passenger compartment circuit at each moment within the preset future time period.

[0053] The duration of the future preset period is longer than the duration of a single management cycle, to ensure that the prediction range covers the complete time window required for the system to respond and stabilize from the current moment.

[0054] After obtaining the predicted temperature values ​​for each thermal management loop, the control unit determines the predicted heat load demand of each thermal management loop within the preset future time period based on the temperature difference between the predicted temperature value and the corresponding target temperature value for each loop. Specifically, the control unit calculates a first difference between the predicted temperature value and the target temperature value of the battery loop at each time, and converts this first difference into the required heat dissipation of the battery loop at each time; calculates a second difference between the predicted temperature value and the target temperature value of the motor loop at each time, and converts this second difference into the required heat dissipation of the motor loop at each time; and calculates a third difference between the predicted temperature value and the target cooling temperature value of the refrigeration loop at each time, and converts this third difference into the required cooling capacity of the refrigeration loop at each time.

[0055] It should be noted that the target battery temperature, target motor temperature, and target cooling temperature are the current temperature control targets for this management cycle, determined after multi-target optimization in the previous management cycle or set during system initialization. The conversion relationship between temperature difference and heat load demand is as follows: the larger the difference, the further the current temperature deviates from the target, and the more heat needs to be removed or supplied. The heat exchange is calculated based on parameters such as coolant specific heat capacity, flow rate, and target heat exchange temperature difference.

[0056] S103. Determine the target operating mode of the pure electric commercial vehicle based on the real-time operating status parameters and the predicted heat load demand.

[0057] Specifically, the control unit determines the target operating mode of the pure electric commercial vehicle in the current management cycle from a preset set of operating modes based on the real-time operating status parameters, including the external ambient temperature, battery temperature, passenger compartment cooling request, and motor operating status, as well as the predicted heat load requirements, including the heat dissipation requirements of the battery circuit, motor circuit, and cooling circuit.

[0058] The set of operating modes includes waste heat recovery heating mode, low cooling demand mode, medium cooling demand mode and high cooling demand mode. Each mode corresponds to a different system architecture connectivity state and actuator control strategy. The control unit realizes the coordinated switching between multiple modes by determining the target operating mode.

[0059] The control unit extracts the current outside temperature, the current battery temperature in the battery circuit, the passenger compartment cooling request status, and the motor operating status from the real-time operating status parameters. Based on the cooling circuit's required cooling capacity, it determines the target operating mode according to the following judgment logic: When the current outside temperature is within the preset heating temperature range, the current battery temperature is below the preset preheating temperature threshold, the motor is operating, and the required cooling capacity of the cooling circuit is less than the preset cooling capacity threshold, the control unit determines the target operating mode as waste heat recovery heating mode. The core of this mode is to utilize the waste heat generated during motor operation to provide heat to the battery and passenger compartment, reducing the energy consumption of the PTC heater. In one embodiment of this application, the preset heating temperature range is -15°C to 20°C, and the preset preheating temperature threshold is 25°C.

[0060] When the current outside temperature is within the first preset cooling temperature range, the current battery temperature is higher than the preset cooling temperature threshold, the passenger compartment cooling request is off, and the cooling circuit's cooling capacity requirement is zero, the control unit determines the target operating mode as a low cooling demand mode. The core of this mode is that when only the battery is cooled and the cooling load is low, the compressor is shut down, and passive cooling is achieved only through the first and second radiators to reduce system energy consumption. In one embodiment of this application, the first preset cooling temperature range is an outside ambient temperature ≤ 20°C, and the preset cooling temperature threshold is 35°C.

[0061] When the current outside temperature is within the second preset cooling temperature range, the current battery temperature is higher than the preset cooling temperature threshold, the passenger compartment cooling request is activated, and the cooling circuit's required cooling capacity is greater than or equal to the preset cooling capacity threshold, the control unit determines the target operating mode as the medium cooling demand mode. The core of this mode is to simultaneously provide active cooling for both the passenger compartment and the battery, with the first radiator simultaneously removing heat from both the water-cooled condenser and the battery circuit. In one embodiment of this application, the second preset cooling temperature range is 20°C to 35°C.

[0062] When the current outside temperature is within the third preset cooling temperature range, the current battery temperature is higher than the preset cooling temperature threshold, the passenger compartment cooling request is enabled, and the cooling circuit's required cooling capacity exceeds the preset cooling capacity threshold, the control unit determines the target operating mode as a high cooling demand mode. The core of this mode is that when the ambient temperature is high and the vehicle's heat dissipation load is large, the compressor speed is increased to increase the cooling capacity, and the coolant side of the water-cooled condenser is switched to the motor thermal management circuit. The second radiator simultaneously dissipates heat from the water-cooled condenser, motor, and electronic control cooling plate, achieving on-demand allocation of heat dissipation resources. In one embodiment of this application, the third preset cooling temperature range is an outside ambient temperature > 35°C.

[0063] In one embodiment of this application, after determining the target operating mode, the control unit further determines whether a smooth transition strategy needs to be executed based on the continuity of mode switching. When the target operating mode changes between two adjacent management cycles, the control unit gradually adjusts the control quantities of each actuator at a preset transition rate to avoid temperature fluctuations or system shocks caused by sudden changes in actuator states during mode switching.

[0064] S104. Using the optimized configuration parameters corresponding to the target operating mode as constraints, and taking the minimization of the total thermal management energy consumption of the pure electric commercial vehicle, the minimization of the first deviation between the battery temperature and the preset battery temperature range, and the minimization of the second deviation between the actual temperature inside the vehicle and the preset comfort temperature range as optimization objectives, construct a multi-objective optimization function.

[0065] Specifically, the control unit determines the optimized configuration parameters corresponding to the target operating mode. The optimized configuration parameters include at least the mode constraints and the weight coefficients of each optimization sub-objective. The multi-objective optimization function is constructed with the optimization objectives of minimizing the total energy consumption of thermal management of the pure electric commercial vehicle, minimizing the first deviation between the battery temperature and the preset battery temperature range, and minimizing the second deviation between the actual temperature inside the vehicle and the preset comfort temperature range.

[0066] In this case, the function expression of the multi-objective optimization function takes the control quantity of each actuator as the independent variable, and the solution result is the optimal control quantity of each actuator.

[0067] The control unit determines the mode constraints based on the target operating mode. The mode constraints include at least the output limiting constraints of each actuator and the thermal balance constraints of each thermal management loop under the target operating mode.

[0068] The output limiting constraints include the minimum and maximum values ​​of compressor speed, the minimum and maximum values ​​of the duty cycle of each water pump flow, the minimum and maximum values ​​of the opening of each electronic expansion valve, the minimum and maximum values ​​of the output power of the PTC heater, and the minimum and maximum values ​​of the opening of each multi-way valve. The above limiting values ​​are determined by the physical characteristics and safe operating boundaries of each component, and the limiting range of each actuator is different in different operating modes.

[0069] For example, in low cooling demand mode, both the lower and upper limits of the compressor speed are zero, and the compressor does not start; in waste heat recovery heating mode, the upper limit of the PTC heater output power is a certain percentage of the rated power, providing auxiliary heating; in cooling mode, the upper limit of the PTC heater output power is zero, and heating is not initiated. Thermal balance constraints include thermodynamic equilibrium conditions such as the cooling capacity equaling the heat load and the radiator heat dissipation equaling the heat carried in by the coolant during steady-state operation of each thermal management loop, ensuring that the optimization solution satisfies energy conservation.

[0070] The control unit determines the weight coefficients of each optimization sub-objective based on the target operating mode. These optimization sub-objectives include minimizing total thermal management energy consumption, minimizing the first deviation between the battery temperature and the preset battery temperature range, and minimizing the second deviation between the actual in-vehicle temperature and the preset comfort temperature range. The weight coefficients characterize the relative importance of each optimization sub-objective in the multi-objective optimization.

[0071] In one embodiment of this application, the weighting coefficients are adaptively switched according to the operating conditions: when the ambient temperature outside the vehicle exceeds the preset extreme temperature range, the weights of the first deviation and the second deviation are increased to prioritize battery safety and passenger cabin comfort; when the ambient temperature outside the vehicle is within the preset mild range, the weight of the total energy consumption of thermal management is increased to prioritize reducing system energy consumption.

[0072] For example, when the outside ambient temperature is below -25℃ or above 45℃, the weighting for battery temperature deviation is set to 0.5, the weighting for passenger compartment temperature deviation is set to 0.4, and the weighting for energy consumption is set to 0.1; when the outside ambient temperature is between 10℃ and 30℃, the weighting for energy consumption is set to 0.6, the weighting for battery temperature deviation is set to 0.3, and the weighting for passenger compartment temperature deviation is set to 0.1. The specific allocation of these weighting values ​​can be optimized and adjusted based on the vehicle calibration results.

[0073] The control unit determines the solution space of the multi-objective optimization function based on the mode constraints. The solution space is the feasible range of control values ​​for each actuator, defined by the output limiting constraint and the thermal balance constraint. Within this solution space, the control unit performs a weighted summation of the total thermal management energy consumption, the first deviation, and the second deviation using the weight coefficients of each optimization sub-objective, and constructs the objective function expression of the multi-objective optimization function using the control values ​​of each actuator as independent variables. J(u) = w1·E_total(u) + w2·ΔT_batt(u) + w3·ΔT_cab(u) Where u represents the control vector of each actuator, E_total(u) represents the total energy consumption of thermal management, including compressor power consumption, water pump power consumption, PTC heater power consumption, and radiator fan power consumption, ΔT_batt(u) represents the deviation of the battery temperature from the preset battery temperature range (this value is zero when the battery temperature is within the preset range), ΔT_cab(u) represents the deviation of the actual temperature of the passenger cabin from the preset comfort temperature range (this value is zero when the actual temperature of the passenger cabin is within the preset comfort temperature range), and w1, w2, and w3 are the corresponding weighting coefficients. By weighted summation, the control unit transforms the multi-objective optimization problem into a single-objective function minimization problem with actuator control variables as independent variables, reducing the solution complexity.

[0074] S105. The model predictive control engine solves the multi-objective optimization function to obtain the optimal control quantity for each actuator, and sends it to the corresponding underlying PID controller to output the drive signal to the corresponding actuator so that the temperature of each thermal management loop approaches the corresponding target temperature.

[0075] Specifically, the control unit solves the multi-objective optimization function through the model predictive control engine, calculates the minimum value of the objective function expression in the solution space, and obtains the optimal control quantity corresponding to each actuator.

[0076] The control unit takes the real-time operating status parameters collected in the current management cycle as the initial state and the current control quantity of each actuator in the current management cycle as the initial solution. Within the solution space, it iteratively updates the control quantity of each actuator along the gradient descent direction of the objective function expression based on the output limiting constraint.

[0077] It should be noted that the gradient descent direction is the direction of the partial derivative of the objective function expression with respect to each actuator control quantity, which is the direction in which the objective function value decreases the fastest.

[0078] The control unit first calculates the gradient vector of the objective function expression at the current solution, then determines the search step size along the gradient descent direction, and uses the current solution plus the product of the search step size and the gradient descent direction vector as the updated solution.

[0079] After each iteration, the control unit determines whether the control quantities of each actuator in the current iteration exceed the output limiting constraints in the mode constraints. If they do, the control quantities of each actuator in the current iteration are limited to fall within the solution space. For example, if the compressor speed in the current iteration exceeds the upper speed limit of the mode, the compressor speed is clamped to the upper speed limit value; if the opening degree of the electronic expansion valve in the current iteration is less than the lower opening limit of the mode, the opening degree of the electronic expansion valve is increased to the lower opening limit value.

[0080] The value of the objective function expression after each iteration is updated and compared with the value of the objective function expression in the previous iteration. When the change in the value of the objective function expression between two adjacent iterations is less than the preset convergence threshold, the iteration is stopped, and the control quantity of each actuator under the current iteration is determined as the optimal control quantity of each actuator.

[0081] The optimal control parameters include compressor speed, flow duty cycle of each water pump, opening degree of each electronic expansion valve, output power of PTC heater, and opening degree of each multi-way valve.

[0082] Furthermore, the control unit sends the optimal control quantity of each actuator to the underlying PID controller of the corresponding thermal management loop. Each underlying PID controller corrects the optimal control quantity based on the current temperature deviation between the current measured temperature value of the corresponding thermal management loop and the current temperature deviation of the corresponding target temperature value in the optimal control quantity, and then outputs a drive signal to the corresponding actuator.

[0083] It should be noted that the underlying PID controller, as the execution unit that tracks the given value of the model predictive control engine, performs minor deviation corrections based on the optimal control quantity issued by the model predictive control engine, ensuring that the measured temperature of each thermal management loop quickly and stably approaches the target temperature.

[0084] The optimal control quantity includes the target temperature value of the corresponding thermal management loop. That is, the optimal control quantity calculated by the model predictive control engine includes the target temperature values ​​of the battery, motor, and passenger compartment, which serve as the temperature setpoints for each underlying PID controller.

[0085] Each underlying PID controller acquires the current measured temperature value of its corresponding thermal management loop and calculates the current temperature deviation between the current measured temperature value and the target temperature value. The current measured temperature value is collected in real time by sensors installed in each loop and provided to the underlying PID controller, including the average battery temperature of the battery loop, the motor winding temperature of the motor loop, and the actual temperature inside the passenger compartment of the passenger compartment loop.

[0086] When the absolute value of the current temperature deviation is less than the preset deviation threshold, each underlying PID controller uses the optimal control quantity as the reference value of the drive signal and directly outputs the drive signal to the corresponding actuator without making additional corrections to the optimal control quantity.

[0087] When the absolute value of the current temperature deviation is greater than or equal to the preset deviation threshold, each underlying PID controller calculates a correction amount based on the proportional, integral, and derivative components of the current temperature deviation, and uses the correction amount to correct and compensate the optimal control quantity, thereby obtaining a corrected drive signal output to the corresponding actuator.

[0088] Furthermore, the control unit uses the management cycle as its execution cycle. After each management cycle ends, the control unit returns to step S101 to obtain the real-time operating status parameters for the next management cycle. Based on the latest collected real-time operating status parameters, it re-executes steps S102 to S106 and updates and sends the newly generated optimal control quantities for each actuator to the underlying actuators in real time, thus achieving rolling time-domain optimization control. The core of this rolling optimization lies in the fact that each management cycle starts with the latest system state and re-performs thermal load prediction and optimization, ensuring that control decisions are always based on the latest information, thereby effectively responding to dynamic changes in vehicle operating conditions.

[0089] This application achieves unified allocation and cross-loop reuse of the vehicle's thermal resources by deeply coupling the refrigeration circuit, battery thermal management circuit, and motor thermal management circuit, and by setting up a waste heat recovery branch. Compared with the traditional distributed architecture where the battery, motor, and air conditioning circuits operate independently, this application can transfer the waste heat generated by the motor to the battery and passenger compartment for heating through the refrigeration circuit. This significantly reduces the dependence on and usage time of the PTC electric heater, effectively reduces the vehicle's power consumption under low-temperature conditions, improves range and energy efficiency, and simplifies the pipeline layout through circuit integration, thereby reducing the overall vehicle cost and failure rate.

[0090] Furthermore, this application employs a model predictive control engine to predict future heat load demands and combines a multi-objective optimization method to dynamically allocate cooling / heating resources among various actuators, minimizing the total energy consumption of vehicle thermal management while meeting the optimal operating temperature range of the battery and the comfort requirements of the passenger compartment. The various embodiments in this application are described in a progressive manner, with similar or identical parts between embodiments readily referentially. Each embodiment focuses on describing the differences from other embodiments. In particular, the device and medium embodiments are basically similar to the method embodiments, so the descriptions are relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0091] The devices and media provided in this application are one-to-one with the methods. Therefore, the devices and media also have similar beneficial technical effects as their corresponding methods. Since the beneficial technical effects of the methods have been described in detail above, the beneficial technical effects of the devices and media will not be repeated here.

[0092] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0093] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0094] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0095] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0096] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0097] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0098] Computer-readable media include both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0099] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0100] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. An integrated thermal management method for pure electric commercial vehicles, characterized in that, The method for applying a thermal management control unit in a pure electric commercial vehicle includes: The system collects real-time operating status parameters of the pure electric commercial vehicle during the current management cycle and obtains historical operating status parameter sequences for historical management cycles. The real-time operating status parameters and the historical operating status parameter sequence are input into the model predictive control engine, which outputs the predicted heat load demand for each thermal management loop within a future preset time period; the thermal management loop includes a refrigeration loop, a battery loop, and a motor loop. The target operating mode of the pure electric commercial vehicle is determined based on the real-time operating status parameters and the predicted heat load demand. Using the optimized configuration parameters corresponding to the target operating mode as constraints, and taking the minimization of the total thermal management energy consumption of the pure electric commercial vehicle, the minimization of the first deviation between the battery temperature and the preset battery temperature range, and the minimization of the second deviation between the actual temperature inside the vehicle and the preset comfort temperature range as optimization objectives, a multi-objective optimization function is constructed. The model predictive control engine solves the multi-objective optimization function to obtain the optimal control quantity for each actuator, and sends it to the corresponding underlying PID controller to output drive signals to the corresponding actuators so that the temperature of each thermal management loop approaches the corresponding target temperature.

2. The integrated thermal management method for a pure electric commercial vehicle according to claim 1, characterized in that, The step of inputting the real-time operating status parameters and the historical operating status parameter sequence into the model predictive control engine and outputting the predicted heat load demand corresponding to each thermal management loop within a future preset time period specifically includes: Extract the temperature change trajectory and load change trajectory of each thermal management loop within a preset historical time period from the historical operating status parameter sequence to construct time-series state features, and extract the current temperature value and current load value of each thermal management loop at the current moment from the real-time operating status parameters to construct current state features; The time-series features and the current state features are input into the model prediction control engine. The model prediction control engine calculates the predicted temperature values ​​for each thermal management loop at each time point within a preset future time period. Based on the temperature difference between the predicted temperature value and the target temperature value of the corresponding thermal management loop, the predicted heat load demand of each thermal management loop in the future preset time period is determined.

3. The integrated thermal management method for a pure electric commercial vehicle according to claim 2, characterized in that, The step of determining the predicted heat load demand of each heat management loop within the preset future time period based on the temperature difference between the predicted temperature value and the target temperature value of the corresponding heat management loop specifically includes: Based on the first difference between the predicted temperature value of the battery circuit and the target temperature value of the battery at each time within the future preset period, the required heat dissipation of the battery circuit at each time within the future preset period is determined. Based on the second difference between the predicted temperature value and the target temperature value of the motor circuit at each moment in the future preset period, the required heat dissipation of the motor circuit at each moment in the future preset period is determined. The required cooling capacity of the refrigeration circuit at each moment in the future preset period is determined based on the third difference between the predicted temperature value and the target cooling temperature value of the refrigeration circuit at each moment in the future preset period.

4. The integrated thermal management method for a pure electric commercial vehicle according to claim 3, characterized in that, The step of determining the target operating mode of the pure electric commercial vehicle based on the real-time operating status parameters and the predicted heat load demand specifically includes: Extract the current outside temperature, the current inside passenger compartment, and the current battery temperature of the battery circuit from the real-time operating status parameters; When the current outside temperature is within the preset heating temperature range, the current battery temperature is below the preset preheating temperature threshold, and the required cooling capacity of the cooling circuit is less than the preset cooling capacity threshold, the target operating mode of the pure electric commercial vehicle is determined to be the waste heat recovery heating mode. When the current outside temperature is within the first preset cooling temperature range, the current battery temperature is higher than the preset cooling temperature threshold, the passenger compartment cooling request is off, and the required cooling capacity is zero, the target operating mode is determined to be a low cooling demand mode. When the current outside temperature is within the second preset cooling temperature range, the battery temperature is higher than the preset cooling temperature threshold, the passenger compartment cooling request is enabled, and the required cooling capacity is not less than the preset cooling capacity threshold, the target operating mode is determined to be the medium cooling demand mode. When the current outside temperature is within the third preset cooling temperature range, the current battery temperature is higher than the preset cooling temperature threshold, the passenger compartment cooling request is enabled, and the required cooling capacity is greater than the preset cooling capacity threshold, the target operating mode is determined to be a high cooling demand mode.

5. The integrated thermal management method for a pure electric commercial vehicle according to claim 1, characterized in that, The step of solving the multi-objective optimization function through the model predictive control engine to obtain the optimal control quantity for each actuator specifically includes: Based on the target operating mode, determine the mode constraints of the multi-objective optimization function and the weight coefficients of each optimization objective; the mode constraints include at least the output limiting constraints of each actuator and the thermal balance constraints of each thermal management loop under the target operating mode. Based on the aforementioned pattern constraints, the solution space of the multi-objective optimization function is determined; Within the solution space, the total energy consumption of thermal management, the first deviation, and the second deviation are weighted and summed based on the weight coefficients corresponding to each optimization objective to obtain the total optimization objective. The function expression of the multi-objective optimization function is then constructed using the control quantities of each actuator as independent variables. Within the solution space, the minimum value of the spatial function expression is calculated to obtain the optimal control quantity corresponding to each actuator; the actuators include a compressor, a water pump, an electronic expansion valve, a PTC heater, and a multi-way water valve.

6. The integrated thermal management method for a pure electric commercial vehicle according to claim 5, characterized in that, The step of calculating the minimum value of the spatial function expression within the solution space to obtain the optimal control quantity corresponding to each actuator specifically includes: Using the real-time running state parameters as the initial state and the current control quantity of each actuator in the current management cycle as the initial solution, within the solution space, based on the output limiting constraint and along the gradient descent direction of the function expression, iteratively update the control quantity corresponding to each actuator. Calculate the solution value of the function expression after each iteration update, and compare it with the previous solution value of the function expression in the previous iteration to determine the change in solution value; When the change in the solution value between two consecutive iterations is less than the preset convergence threshold, the iteration stops, and the solution value of the function expression in the current iteration is determined as the optimal control value for each actuator.

7. The integrated thermal management method for a pure electric commercial vehicle according to claim 1, characterized in that, The process of sending the signal to the corresponding underlying PID controller and outputting the drive signal to the corresponding actuator specifically includes: The optimal control input of each actuator is sent to the underlying PID controller of the corresponding thermal management loop. The underlying PID controller calculates the current actual temperature deviation between the current measured temperature value and the target temperature value of the corresponding thermal management loop based on the current measured temperature value of the corresponding thermal management loop. When the absolute value of the current actual temperature deviation is less than the preset deviation threshold, the optimal control quantity is used as the reference value of the drive signal, and the drive signal is output to the corresponding actuator. When the absolute value of the current actual temperature deviation is not less than the preset deviation threshold, a correction amount is calculated based on the current actual temperature deviation, and the optimal control amount is corrected and compensated based on the correction amount to obtain a corrected drive signal output to the corresponding actuator.

8. An integrated thermal management system for a pure electric commercial vehicle, characterized in that, Applications include pure electric commercial vehicles, including: The refrigeration circuit includes a compressor, a water-cooled condenser, an evaporator, and an electronic expansion valve. The first refrigerant outlet of the water-cooled condenser is connected to the second refrigerant inlet of the evaporator and the third refrigerant inlet of the battery cooler. The second refrigerant outlet and the third refrigerant outlet are both connected to the fourth refrigerant inlet of the compressor. The battery thermal management circuit includes a battery water-cooling plate, a first water pump, a PTC heater, a first radiator, and the battery cooler. The battery water-cooling plate, the PTC heater, the first radiator, and the battery cooler are connected by a multi-way valve to form a battery cooling branch and a battery heating branch. The motor thermal management circuit includes a motor water jacket, an electronic control cooling plate, a second water pump, and a second radiator. The motor water jacket, the electronic control cooling plate, and the second radiator are connected by a multi-way valve. The motor thermal management circuit is selectively connected to the battery cooler through the multi-way valve to transfer the motor's waste heat to the cooling circuit. The control unit is connected to the compressor, each of the electronic expansion valves, each of the water pumps, the PTC heater, and each of the multi-way valves, and the control unit is configured to perform an integrated thermal management method for a pure electric commercial vehicle as described in any one of claims 1-7.

9. An integrated thermal management system for a pure electric commercial vehicle according to claim 8, characterized in that, The multi-way valve includes a first multi-way valve, a second multi-way valve, a third multi-way valve, and a fourth multi-way valve; The outlet of the battery water-cooling plate is connected to the first port of the first multi-way valve, the second port of the first multi-way valve is connected to the inlet of the PTC heater, the third port of the first multi-way valve is connected to the inlet of the first radiator, and the fourth port of the first multi-way valve is connected to the first port of the second multi-way valve; the outlet of the PTC heater is connected to the coolant inlet of the refrigerant-coolant heat exchanger, the coolant outlet of the refrigerant-coolant heat exchanger is connected to the first port of the third multi-way valve, the second port of the third multi-way valve is connected to the inlet of the battery water-cooling plate, and the third port of the third multi-way valve is connected to the first port of the fourth multi-way valve; the outlet of the first radiator is connected to the second port of the fourth multi-way valve, the third port of the fourth multi-way valve is connected to the inlet of the first water pump, and the outlet of the first water pump is connected to the inlet of the battery water-cooling plate; The outlet of the motor water jacket is connected to the second port of the second multi-way valve, the third port of the second multi-way valve is connected to the inlet of the second radiator, the outlet of the second radiator is connected to the inlet of the second water pump, and the outlet of the second water pump is connected to the inlet of the motor water jacket.

10. An integrated thermal management system for a pure electric commercial vehicle according to claim 9, characterized in that: In the waste heat recovery heating mode, the first multi-way valve connects its first port and its second port, the second multi-way valve connects its first port and its second port, the third multi-way valve connects its first port and its second port, and the fourth multi-way valve is disconnected. In the low cooling demand mode, the first multi-way valve connects its first port and its third port, the second multi-way valve connects its second port and its third port, the third multi-way valve connects its second port and its third port, and the fourth multi-way valve connects its first port and its second port. In the medium cooling demand mode, the first multi-way valve connects its first port and its fourth port, the second multi-way valve connects its first port and its second port, the third multi-way valve connects its first port and its third port, and the fourth multi-way valve connects its first port and its second port. In the high cooling demand mode, the first multi-way valve connects its first port and fourth port, the second multi-way valve connects its first port and third port, the third multi-way valve connects its first port and third port, the fourth multi-way valve connects its first port and second port, and the coolant side of the water-cooled condenser is connected in series to the motor thermal management circuit.

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