Off-highway dump truck and its thermal management integrated system and control method

Abstract

This invention discloses an integrated thermal management system for off-highway dump trucks, relating to the field of engineering vehicle technology. The invention aims to solve the problems of high energy consumption at low temperatures and short compressor lifespan in existing systems. The technical solution includes: a first thermal management unit and a second thermal management unit, each integrating a compressor and a low-temperature radiator; a control module is used to acquire the ambient temperature. When the ambient temperature is lower than a preset temperature threshold, the control unit enters a low-temperature cooling mode, shutting down the compressor and activating the low-temperature radiator for cooling; when the ambient temperature is not lower than the threshold, it enters a compressor cooling mode, activating the compressor for cooling via a plate heat exchanger. This invention is mainly used in new energy off-highway dump trucks, intelligently switching cooling modes to utilize natural cold sources for compressor-free cooling at low temperatures, significantly reducing battery cooling energy consumption and extending compressor lifespan.

Description

Technical Field

[0001] This invention relates to the field of engineering vehicle technology. More specifically, this invention relates to an off-highway dump truck and its integrated thermal management system and control method. Background Technology

[0002] Off-highway dump trucks are large engineering vehicles specifically designed for harsh working conditions such as open-pit coal mines, metal mines, and large-scale engineering projects, undertaking short-distance transportation tasks for materials such as ore and earthwork.

[0003] With the advancement of green mining construction, the application of new energy off-highway dump trucks is becoming increasingly widespread. Their vehicle thermal management systems, as crucial for ensuring the safe and efficient operation of core components such as batteries, motors, and electronic controls, have received widespread attention. Currently common solutions on the market include, for example, a battery thermal management cooling system and method for off-highway dump trucks described in Chinese patent application CN121507205A, which uses a single battery thermal management unit to uniformly regulate the coolant temperature. Alternatively, existing decentralized thermal management systems can independently arrange subsystems such as battery thermal management, air conditioning, and motor / electronic control cooling.

[0004] However, existing thermal management technologies have the following shortcomings. Traditional distributed systems lack functional and structural integration between subsystems, resulting in a large number of components and significant space requirements. This not only increases overall vehicle manufacturing costs but also raises the failure rate due to complex wiring harnesses and redundant piping. In low-temperature winter environments, existing battery cooling solutions typically still rely on compressors for cooling. Since compressor cooling efficiency is extremely low at low temperatures (ideally only 2 COP, and even below 1 at low temperatures), this results in significant energy waste. Furthermore, the frequent start-stop cycles of compressors at low temperatures severely shorten their lifespan. In addition, a large amount of waste heat generated by the motor during operation is usually directly discharged into the air by the cooling system without effective utilization. Meanwhile, winter heating in the cab relies on PTC heaters, consuming a large amount of electricity. This energy waste further reduces the vehicle's economy and range.

[0005] Therefore, how to achieve cost reduction and efficiency improvement, energy consumption reduction, extension of key component life and improvement of energy utilization efficiency through system integration while ensuring various thermal management functions has become an urgent technical problem to be solved in the field of thermal management technology for new energy off-highway dump trucks. Summary of the Invention

[0006] One object of the present invention is to provide an integrated thermal management system for off-highway dump trucks, comprising: The first thermal management unit integrates the first compressor and the first low-temperature radiator. The second thermal management unit integrates a second compressor and a second low-temperature radiator. The battery pack has a first coolant inlet, a second coolant inlet, a first coolant outlet, and a second coolant outlet; The first coolant circuit is connected between the coolant inlet and outlet of the first thermal management unit and the first coolant inlet and the first coolant outlet of the battery pack, forming a first independent circulation branch. The second coolant circuit is connected between the coolant inlet and outlet of the second thermal management unit and the second coolant inlet and the second coolant outlet of the battery pack, forming a second independent circulation branch; The control module is used to acquire the ambient temperature; When the ambient temperature is lower than a first preset temperature threshold, the first thermal management unit and / or the second thermal management unit are controlled to enter a low-temperature cooling mode. In the low-temperature cooling mode, the first compressor and / or the second compressor are turned off, and the first low-temperature radiator and / or the second low-temperature radiator are started to cool the coolant and cool the battery pack. When the ambient temperature is not lower than the first preset temperature threshold, the first thermal management unit and / or the second thermal management unit are controlled to enter the compressor cooling mode. In the compressor cooling mode, the first compressor and / or the second compressor are started, and the coolant is cooled through the plate heat exchanger to cool the battery pack.

[0007] Preferably, it also includes: Drive motor; An electric motor cooling circuit includes an electric motor radiator, wherein the inlet of the electric motor radiator is connected to the outlet of the drive motor via a first water pump, and the outlet of the electric motor radiator is connected to the inlet of the drive motor. An electronically controlled heat dissipation circuit includes an electronically controlled radiator, wherein the inlet of the electronically controlled radiator is connected to the outlet of the motor controller via a second water pump, and the outlet of the electronically controlled radiator is connected to the inlet of the motor controller. The heating circuit includes a heating core, the outlet of which is selectively connected to the inlet of the motor radiator via a second three-way valve. The inlet of the second three-way valve is connected to the outlet of the heating core, one outlet of the second three-way valve is connected to the inlet of the motor radiator, and the other outlet of the second three-way valve is connected to the inlet of the PTC heater. The control module is also used to control the connection between the heating circuit and the motor heat dissipation circuit when the motor waste heat recovery conditions are met, so that the coolant from the drive motor flows through the heating core and the waste heat of the drive motor is used to heat the cab. Furthermore, the control module is also used to control the exit of the motor waste heat recovery mode and control the PTC heater to start for auxiliary heating when the indoor temperature exceeds the sum of the set temperature and the preset exit temperature difference threshold, or when the outlet temperature of the drive motor is lower than the preset exit temperature threshold.

[0008] Preferably, the first thermal management unit and / or the second thermal management unit further include a two-position three-way valve, which is located upstream of the low-temperature radiator and is used for: In the low-temperature cooling mode, the coolant is directed to the low-temperature radiator; The low-temperature radiator is bypassed in the compressor cooling mode.

[0009] Preferably, the control module further includes a hysteresis interval unit, which is used to set a hysteresis interval according to the first preset temperature threshold. The hysteresis interval is used to control the ambient temperature threshold when the low-temperature cooling mode exits to be higher than the first preset temperature threshold.

[0010] Preferably, the heat dissipation power of the motor radiator is less than that of the electronic control radiator.

[0011] Preferably, it also includes a control integration interface, which is disposed on the housing of the first thermal management unit or the second thermal management unit, and the control integration interface is electrically connected to the wiring harness of the first thermal management unit and / or the second thermal management unit.

[0012] Preferably, the refrigerant circuit of the first thermal management unit and / or the second thermal management unit includes: The first electromagnetic expansion valve is installed on the refrigerant pipeline leading to the air conditioner evaporator. The second electromagnetic expansion valve is installed on the refrigerant pipeline leading to the solar panel heat exchanger. The control module is also used to reduce the opening of the first electromagnetic expansion valve and increase the opening of the second electromagnetic expansion valve when the first thermal management unit and / or the second thermal management unit malfunctions.

[0013] Preferably, the two-position three-way valve inside the first thermal management unit and / or the second thermal management unit has the following switching states: In the first state, the low-temperature radiator is bypassed, allowing the coolant to circulate within the thermal management unit; In the second state, the low-temperature radiator is connected, allowing the coolant to flow through the low-temperature radiator for heat dissipation; The control module is used to control the two-position three-way valve to switch between the first state and the second state according to the temperature of the coolant or the ambient temperature in the low-temperature refrigeration mode.

[0014] A control method for the aforementioned off-highway dump truck thermal management integrated system is provided, comprising the following steps: S1. Obtain the ambient temperature; S2. Determine whether the ambient temperature is lower than the first preset temperature threshold. If yes, enter the low-temperature cooling mode, shut down the compressor inside the first thermal management unit and / or the second thermal management unit, and start the corresponding low-temperature radiator to cool the coolant and cool the battery pack. If no, enter the compressor cooling mode, start the compressor inside the first thermal management unit and / or the second thermal management unit, and cool the coolant through the plate heat exchanger to cool the battery pack. S3. In the low-temperature refrigeration mode, according to the temperature of the coolant or the ambient temperature, the two-position three-way valve located upstream of the low-temperature radiator is controlled to switch between a first state that bypasses the low-temperature radiator and a second state that connects to the low-temperature radiator. S4. Set a hysteresis range according to the first preset temperature threshold. When the ambient temperature rises from below the first preset temperature threshold to above the second preset temperature threshold within the hysteresis range, control the exit of the low-temperature cooling mode. S5. When the motor waste heat recovery conditions are met, control the switching of the first three-way valve and the second three-way valve, connect the heating circuit and the motor heat dissipation circuit, and the coolant from the drive motor flows through the heating core to heat the cab using the waste heat of the drive motor; when the indoor temperature exceeds the sum of the set temperature and the preset exit temperature difference threshold, or when the outlet temperature of the drive motor is lower than the preset exit temperature threshold, control the exit of the motor waste heat recovery mode and control the PTC heater to start for auxiliary heating. S6. Control signals are transmitted by electrically connecting the control integration interface provided on the housing of the first thermal management unit or the second thermal management unit to the wiring harness of the first thermal management unit and / or the second thermal management unit. S7. When the first thermal management unit and / or the second thermal management unit malfunctions, the opening of the first electromagnetic expansion valve on the refrigerant pipeline leading to the air conditioning evaporator is reduced, and the opening of the second electromagnetic expansion valve on the refrigerant pipeline leading to the solar panel heat exchanger is increased.

[0015] An off-highway dump truck is provided, including the off-highway dump truck thermal management integrated system as described above.

[0016] The present invention has at least the following beneficial effects: First, the present invention sets up a first thermal management unit and a second thermal management unit, and introduces a first preset temperature threshold to intelligently switch between low-temperature cooling mode and compressor cooling mode. When the ambient temperature is lower than the set value, the compressor is turned off and natural air cooling is carried out using a low-temperature radiator, which reduces the operating time of the compressor in the low-temperature and low-efficiency zone, reduces the energy consumption of the battery cooling process, and avoids frequent start-stop of the compressor at low temperatures, which helps to extend the service life of the compressor.

[0017] Secondly, by physically separating the motor cooling circuit from the electronic control cooling circuit, and selectively connecting the heating circuit and the motor cooling circuit using the first three-way valve and the second three-way valve, the present invention realizes the recovery and utilization of the waste heat of the drive motor, and introduces the motor waste heat that was originally lost to the environment into the cab for winter heating, thereby reducing the power consumption of the PTC heater, improving the energy utilization efficiency of the whole vehicle, and correspondingly improving the vehicle's range.

[0018] Third, by setting a hysteresis interval unit in the control module, the present invention ensures that the exit temperature threshold of the low-temperature refrigeration mode is higher than the entry temperature threshold, effectively avoiding frequent switching between the low-temperature refrigeration mode and the compressor refrigeration mode when the ambient temperature fluctuates near the set threshold, thus guaranteeing the stability and reliability of the system operation.

[0019] Fourth, by setting a control integration interface on the housing of the thermal management unit, the present invention connects various wiring harnesses inside the unit to this interface in a centralized manner, which simplifies the wiring harness layout of the whole vehicle, reduces assembly processes and wiring harness costs, and reduces the risk of failure caused by too many wiring harness connectors, which helps to improve the overall reliability of the system and reduce manufacturing costs.

[0020] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the system according to one of the technical solutions of the present invention; Figure 2 This is a flowchart of the control method according to one of the technical solutions of the present invention.

[0022] The markings in each of the attached figures are as follows: 1. First thermal management unit; 2. Second thermal management unit; 3. Battery pack; 4. Control module; 5. Drive motor; 6. Motor controller; 7. Motor radiator; 8. Electrically controlled radiator; 9. Heater core; 10. PTC heater; 11. First water pump; 12. Second water pump; 13. Third water pump; 14. First three-way valve; 15. Second three-way valve; 16. Ambient temperature sensor; 17. Control integration interface; 18. First coolant circuit; 19. Second coolant circuit; 20. Motor cooling circuit; 21. Electrically controlled cooling circuit; 22. Heater circuit. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0024] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are conventional methods, and the reagents and materials mentioned are commercially available unless otherwise specified. In the description of this invention, the orientations or positional relationships indicated by terms are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. The terms "first," "second," etc., used in this invention are only used to distinguish different components and are not used to indicate order or importance.

[0025] like Figures 1-2 As shown, the present invention provides an integrated thermal management system for off-highway dump trucks, comprising: The first thermal management unit 1 integrates a first compressor and a first low-temperature radiator. Specifically, the first thermal management unit 1 can be a highly integrated unit, with a first compressor and a first low-temperature radiator integrated in its casing. The first compressor can be an electric scroll compressor used to compress refrigerant in compressor cooling mode. The first low-temperature radiator can be an aluminum tube-and-fin radiator that shares an electric fan with the first condenser on the roof or frame for natural air cooling of the coolant in low-temperature environments. The second thermal management unit 2 integrates a second compressor and a second low-temperature radiator. Specifically, the second thermal management unit 2 integrates a second compressor and a second low-temperature radiator. The second compressor can be an electric scroll compressor of the same specifications or with slightly lower power to adapt to different cooling load requirements. The second low-temperature radiator can be an aluminum radiator with a similar structure to the first low-temperature radiator but with different dimensions. The first thermal management unit 1 and the second thermal management unit 2 can have the same structure to facilitate platform design, or they can be units of different specifications selected according to functional requirements. The battery pack 3 has a first coolant inlet, a second coolant inlet, a first coolant outlet, and a second coolant outlet. Specifically, there can be one or more battery packs 3, and each battery pack 3 is composed of multiple battery packs connected in series or in parallel. In order to achieve refined management of the battery pack 3, the battery pack 3 is designed to have independent coolant inlets and outlets, specifically including a first coolant inlet, a second coolant inlet, a first coolant outlet, and a second coolant outlet. These inlets and outlets can be located on both sides or the same side of the battery pack 3 casing. The first coolant circuit 18 is connected between the coolant inlet and outlet of the first thermal management unit 1 and the first coolant inlet and outlet of the battery pack 3, forming a first independent circulation branch; specifically, the first coolant circuit 18 connects the coolant outlet of the first thermal management unit 1 to the first coolant inlet of the battery pack 3 through a pipe, and connects the first coolant outlet of the battery pack 3 to the coolant inlet of the first thermal management unit 1, forming a first independent parallel circulation; The second coolant circuit 19 connects the coolant inlet and outlet of the second thermal management unit 2 with the second coolant inlet and second coolant outlet of the battery pack 3, forming a second independent circulation branch. Specifically, the second coolant circuit 19 connects the second thermal management unit 2 with the second coolant inlet and second coolant outlet of the battery pack 3 in the same way, forming a second independent parallel circulation. The first coolant circuit 18 and the second coolant circuit 19 are arranged in parallel with respect to the battery pack. This dual-circuit parallel design allows the two thermal management units to perform thermal management on the battery pack 3 simultaneously or separately. Control module 4 is used to acquire ambient temperature. Specifically, in order to control the entire system, the system is configured with a control module 4. The control module 4 can be the vehicle controller on the vehicle or a dedicated thermal management domain controller. The control module 4 is connected to the ambient temperature sensor 16 on the vehicle via the CAN bus to acquire the current ambient temperature signal. Specifically, when the ambient temperature is lower than the first preset temperature threshold, the first thermal management unit 1 and / or the second thermal management unit 2 are controlled to enter the low-temperature cooling mode. In the low-temperature cooling mode, the first compressor and / or the second compressor are turned off, and the first low-temperature radiator and / or the second low-temperature radiator are started to cool the coolant and cool the battery pack 3. Specifically, when the control module 4 determines that the ambient temperature is lower than the first preset temperature threshold, which can be set to -5℃, the corresponding first thermal management unit 1 or the second thermal management unit 2 is controlled to enter the low-temperature cooling mode. In this mode, the control module 4 will send a command to turn off the corresponding first compressor or second compressor, and at the same time control the corresponding electronic fan to start, and control the two-position three-way valve inside the unit to switch the coolant to flow through the low-temperature radiator. At this time, the high-temperature coolant from the battery pack 3 is cooled naturally by air convection in the low-temperature radiator, and then flows back to the battery pack 3 to achieve low-energy cooling. When the ambient temperature is not lower than the first preset temperature threshold, the first thermal management unit 1 and / or the second thermal management unit 2 are controlled to enter the compressor cooling mode. In the compressor cooling mode, the first compressor and / or the second compressor are started, and the coolant is cooled through the plate heat exchanger to cool the battery pack 3. Specifically, when the ambient temperature is not lower than the first preset temperature threshold, for example, when the temperature is 0°C or 10°C, the compressor cooling mode is entered. In this mode, the control module 4 starts the first compressor or the second compressor and controls the two-position three-way valve to switch to the bypass low-temperature radiator passage, so that the coolant flows through the plate heat exchanger. The refrigerant driven by the compressor undergoes forced heat exchange with the coolant in the plate heat exchanger, carrying away the heat in the coolant and dissipating it into the environment, thereby achieving efficient active cooling.

[0026] In the above technical solution, the working process of the off-highway dump truck thermal management integrated system is as follows: First, the ambient temperature is obtained through the control module 4. When the ambient temperature is lower than the first preset temperature threshold, the system enters the low-temperature cooling mode, shuts down the compressor, and starts the low-temperature radiator to cool the battery pack 3 using natural air cooling. When the ambient temperature is not lower than the first preset temperature threshold, the system enters the compressor cooling mode, starts the compressor, and performs active cooling through the plate heat exchanger. Through the above structure and working mode, the thermal management integrated system of the present invention achieves the purpose of intelligently switching the cooling mode according to the ambient temperature. In winter, when the temperature is low, free air cooling is achieved by using the low-temperature radiator, avoiding the need for compressor cooling. The compressor operates in the low-efficiency zone, significantly reducing energy consumption and extending compressor life. In the high temperatures of summer, it switches back to the high-efficiency compressor for cooling, ensuring that the temperature of battery pack 3 is within a safe range. This mode switching based on ambient temperature ensures that the battery cooling system always operates at the optimal balance between energy consumption and efficiency. In addition, the dual-redundancy design of the first thermal management unit 1 and the second thermal management unit 2 provides the system with higher reliability. Even if one unit fails, the other unit can still work, providing the vehicle with the ability to limp home. At the same time, since the water circuits of the two units are merged externally before entering the battery, the temperature uniformity of the coolant in the battery water circuit can be greatly improved.

[0027] Another technical solution also includes: Drive motor 5; specifically, drive motor 5 can be two permanent magnet synchronous motors installed in parallel for driving the vehicle; The motor cooling circuit 20 includes a motor radiator 7. The inlet of the motor radiator 7 is connected to the outlet of the drive motor 5 through a first water pump 11, and the outlet of the motor radiator 7 is connected to the inlet of the drive motor 5. Specifically, the motor cooling circuit 20 includes a motor radiator 7, which can be an aluminum tube-strip radiator with a size selectable between 600mm×400mm and 1000mm×600mm. The inlet of the motor radiator 7 is connected to the outlet of the drive motor 5 through a first water pump 11, which can be an electronic water pump with a rated voltage of 24V or 48V and a rated power selectable between 100W and 300W. The outlet of the motor radiator 7 is directly connected to the inlet of the drive motor 5, forming a closed loop. The electrically controlled heat dissipation circuit 21 includes an electrically controlled radiator 8. The inlet of the electrically controlled radiator 8 is connected to the outlet of the motor controller 6 via a second water pump 12, and the outlet of the electrically controlled radiator 8 is connected to the inlet of the motor controller 6. Specifically, the electrically controlled heat dissipation circuit 21 is an independent design, which includes an electrically controlled radiator 8. The electrically controlled radiator 8 can be a larger aluminum radiator with stronger heat dissipation performance, and its size can be selected between 800mm×500mm and 1200mm×800mm. The inlet of the electrically controlled radiator 8 is connected to the outlet of the motor controller 6 via a second water pump 12. The second water pump 12 can also be an electronic water pump, and its specifications can be the same as or different from the first water pump 11. The outlet of the electrically controlled radiator 8 is connected to the inlet of the motor controller 6, forming another independent loop. This design, which physically separates the motor and the electrically controlled heat dissipation circuit 21, can make the heat dissipation power of the motor radiator 7 less than that of the electrically controlled radiator 8, because the heat resistance of the motor is usually better than that of the electrically controlled radiator 8. The heating circuit 22 includes a heating core 9. The outlet of the heating core 9 is selectively connected to the inlet of the motor radiator 7 via a second three-way valve 15. The inlet of the second three-way valve 15 is connected to the outlet of the heating core 9, one outlet of the second three-way valve 15 is connected to the inlet of the motor radiator 7, and the other outlet of the second three-way valve 15 is connected to the inlet of the PTC heater 10. Specifically, the core of the heating circuit 22 is a heating core 9 installed in the cab air conditioning unit. The heating core 9 can be a tube-plate heat exchanger composed of brass tubes and aluminum fins. Its size can be selected according to the cab space, for example, between 200mm×150mm and 400mm×300mm. The inlet of the heating core 9 can be connected to the drive unit via a third water pump 13 and a first three-way valve 14. The outlet of the drive motor 5 is selectively connected. Specifically, the inlet of the first three-way valve 14 is connected to the outlet of the drive motor 5, one outlet of the first three-way valve 14 is connected to the inlet of the motor radiator 7, and the other outlet of the first three-way valve 14 is connected to the inlet of the heater core 9 through the third water pump 13. The outlet of the heater core 9 is selectively connected to the inlet of the motor radiator 7 through the second three-way valve 15. The inlet of the second three-way valve 15 is connected to the outlet of the heater core 9, one outlet of the second three-way valve 15 is connected to the inlet of the motor radiator 7, and the other outlet of the second three-way valve 15 is connected to the inlet of the PTC heater 10. The PTC heater 10 can be a liquid heater with a rated power selectable between 3kW and 10kW, used for auxiliary heating when there is no residual heat. Among them, the control module 4 is also used to control the connection between the heating circuit 22 and the motor heat dissipation circuit 20 when the motor waste heat recovery conditions are met, so that the coolant from the drive motor 5 flows through the heating core 9 and uses the waste heat of the drive motor 5 to heat the cab. Furthermore, the control module 4 is also used to control the motor waste heat recovery mode to exit when the indoor temperature exceeds the sum of the set temperature and the preset exit temperature difference threshold, or when the outlet temperature of the drive motor 5 is lower than the preset exit temperature threshold, and to control the PTC heater 10 to start auxiliary heating. Specifically, when the control module 4 detects that "the temperature of the motor body exceeds the set value TM1 (e.g., 80℃)" and "the difference between the set temperature of the cab and the indoor temperature is less than TM3 (e.g., 5℃) and the temperature of the motor outlet exceeds TM4 (e.g., 70℃)," it considers the conditions for motor waste heat recovery to be met. At this time, the control module 4 controls the switching of the first three-way valve 14 and the second three-way valve 15, so that the inlet of the first three-way valve 14 is connected to the outlet connected to the third water pump 13, and the inlet of the second three-way valve 15 is connected to the outlet connected to the motor radiator 7. In this way, the high-temperature coolant flowing out of the drive motor 5 no longer flows to the motor radiator 7 for heat dissipation, but first flows through the heater core 9, using the motor waste heat to heat the cab. The cooled coolant, after being exchanged and cooled, flows back to the drive motor 5 to complete the cycle. In this mode, the fan of the motor radiator 7 and the first water pump 11 can be turned off or their speed reduced to save energy. When the temperature inside the cab exceeds the sum of the set temperature and the preset exit temperature difference threshold, for example, exceeding 2°C, or when the outlet temperature of the drive motor 5 is lower than the preset exit temperature threshold, for example, lower than 55°C, the control module 4 controls the exit of the motor waste heat recovery mode, resets the first three-way valve 14 and the second three-way valve 15, and allows the coolant to flow back to the motor radiator 7. At the same time, if the cab still needs heating, the PTC heater 10 is activated to provide auxiliary heating to the coolant by electric heating to ensure continuous heating of the cab.

[0028] Through the above structure and working method, the present invention achieves efficient recovery and utilization of waste heat from the drive motor 5.

[0029] In another technical solution, the first thermal management unit 1 and / or the second thermal management unit 2 further include a two-position three-way valve, which is located upstream of the low-temperature radiator and is used for: In low-temperature cooling mode, the coolant is directed to the low-temperature radiator; In compressor cooling mode, bypass the low-temperature radiator; Specifically, this invention provides more precise control over the coolant flow direction within the first thermal management unit 1 or the second thermal management unit 2. The first thermal management unit 1 and / or the second thermal management unit 2 include a key two-position three-way valve. This valve is located upstream of the cryogenic radiator, for example, it can be installed on the pipeline flowing from the plate heat exchanger and before entering the cryogenic radiator within the unit. The inlet of the two-position three-way valve connects to the coolant pipeline from the plate heat exchanger, and its two outlets connect to the inlet of the cryogenic radiator and a bypass pipeline, respectively. In cryogenic cooling mode, the control module 4 controls the two-position three-way valve to switch to the first operating state, that is, to connect its inlet to the outlet leading to the cryogenic radiator. At this time, the coolant is forced to the low-temperature radiator, where it is cooled by the cold air blown by the fan, achieving low-energy battery cooling. In the compressor cooling mode, the control module 4 controls the two-position three-way valve to switch to the second working state, that is, to connect its inlet with the outlet of the bypass low-temperature radiator. At this time, the coolant bypasses the low-temperature radiator and flows directly back to the plate heat exchanger. During this process, the compressor refrigerant circuit in the plate heat exchanger is working. When the coolant flows through the plate heat exchanger, it will have efficient heat exchange with the refrigerant, thereby achieving active cooling. By setting this two-position three-way valve, the system can flexibly switch between the two cooling modes and achieve precise control of the coolant passage without complex piping layout.

[0030] In another technical solution, the control module 4 further includes a hysteresis interval unit, which is used to set a hysteresis interval based on a first preset temperature threshold. The hysteresis interval is used to control the ambient temperature threshold when the low-temperature cooling mode exits to be higher than the first preset temperature threshold. Specifically, the control module 4 also embeds a hysteresis interval unit to optimize the switching logic of the low-temperature cooling mode and prevent the mode from frequently changing near the threshold. The control module 4 automatically sets a hysteresis interval based on the preset first preset temperature threshold, such as -5℃. The range of the hysteresis interval can be set according to the system characteristics, for example, it can be set to a temperature window from -5℃ to -3℃. Its working principle is: when the ambient temperature... When the temperature drops below -5℃, control module 4 switches to low-temperature cooling mode. Subsequently, if the ambient temperature fluctuates around -5℃, the system will not immediately exit the low-temperature cooling mode. Instead, it will wait until the ambient temperature rises steadily to above the upper limit of the hysteresis range, such as -3℃, before exiting the low-temperature cooling mode and switching to compressor cooling mode. This "ambient temperature threshold at exit" is higher than the "first preset temperature threshold at entry," thus forming a temperature hysteresis band. This hysteresis range effectively avoids frequent switching between the two modes when the temperature difference is small, ensuring the stability of system operation and the service life of the compressor, improving user experience and system reliability.

[0031] In another technical solution, the heat dissipation power of the motor radiator 7 is less than that of the electronically controlled radiator 8. Specifically, the motor radiator 7 and the electronically controlled radiator 8 are designed with differentiated configurations. The heat dissipation power of the motor radiator 7 can be less than that of the electronically controlled radiator 8. This can be achieved by selecting radiators of different sizes or with different heat dissipation performance. For example, the motor radiator 7 can be a smaller, thinner core, and lower fin density double-row aluminum radiator, while the electronically controlled radiator 8 can be a larger, thicker core, and higher fin density four-row aluminum radiator. This design is based on the motor and motor control. Due to the different thermal characteristics of the motor controller 6, the permanent magnet synchronous motor has a wide operating temperature range, typically allowing operating temperatures above 100℃. Its heat originates from winding copper losses and core iron losses, resulting in a large heat capacity. In contrast, the power modules inside the motor controller 6, such as IGBTs, are more sensitive to temperature, typically operating below 85℃, and have higher heat dissipation requirements. Therefore, physically separating the cooling systems of the motor and the controller and using radiators of different power allows for a more rational and precise allocation of cooling resources. This avoids over-equipping the motor with an excessively large radiator to meet the cooling needs of the controller, effectively reducing the overall vehicle cost, weight, and space occupation.

[0032] In another technical solution, a control integration interface 17 is also included, which is disposed on the housing of the first thermal management unit 1 or the second thermal management unit 2, and the control integration interface 17 is electrically connected to the wiring harness of the first thermal management unit 1 and / or the second thermal management unit 2. Specifically, the control integration interface 17 can be a multi-in-one waterproof connector that integrates high-voltage connectors, low-voltage connectors, and CAN communication connectors. The control integration interface 17 is located on the housing of the first thermal management unit 1 or the housing of the second thermal management unit 2. For example, it can be fixed on the side wall of its housing or integrated into the top cover of the unit. The internal control harness, high-voltage harness, and low-voltage harness of the unit are pre-connected to the internal terminal block of the control integration interface 17. During vehicle assembly, only one trunk harness from the vehicle controller or thermal management domain controller needs to be plugged into the control integration interface 17 to complete the power supply, communication, and control signal connection of the entire thermal management system. This design simplifies the connection method that originally required connecting multiple scattered harnesses such as compressor, PTC heater 10, fan, water pump, various valves, and sensors separately into a unified interface, which greatly simplifies the overall vehicle harness layout, reduces assembly difficulty and harness cost, and improves the protection level and reliability of the system by reducing exposed harness connectors.

[0033] In another technical solution, the refrigerant circuit of the first thermal management unit 1 and / or the second thermal management unit 2 includes: The first electromagnetic expansion valve is installed on the refrigerant pipeline leading to the air conditioner evaporator. The second electromagnetic expansion valve is installed on the refrigerant pipeline leading to the solar panel heat exchanger. The control module 4 is also used to reduce the opening of the first electromagnetic expansion valve and increase the opening of the second electromagnetic expansion valve when the first thermal management unit 1 and / or the second thermal management unit 2 malfunction. Specifically, the present invention further defines the control logic of the refrigerant circuit. In the refrigerant circuit of the first thermal management unit 1 or the second thermal management unit 2, electromagnetic expansion valves are installed in the pipelines leading to different evaporators. Specifically, they include: a first electromagnetic expansion valve, which is installed on the refrigerant pipeline from the condenser to the air conditioning evaporator, with its inlet connected to the outlet of the condenser and its outlet connected to the inlet of the air conditioning evaporator; and a second electromagnetic expansion valve, which is installed on the refrigerant pipeline from the condenser to the solar panel heat exchanger, with its inlet connected to the outlet of the condenser and its outlet connected to the refrigerant inlet of the solar panel heat exchanger. These two electromagnetic expansion valves can be electronic expansion valves driven by stepper motors, with their valve needle strokes ranging from 0 to 10 mm, enabling precise control of the refrigerant flow rate. Control module 4 is programmed to execute a protective control strategy when a fault is detected in either the first thermal management unit 1 or the second thermal management unit 2, such as compressor failure or refrigerant leakage in one unit. In this case, control module 4 will reduce the opening of the first electromagnetic expansion valve, for example, from the normal 50% opening to 10% opening, thereby significantly reducing the refrigerant flow to the evaporator of the cab air conditioning unit. Control module 4 will also increase the opening of the second electromagnetic expansion valve, for example, from the normal 50% opening to 100% opening, thereby directing most of the remaining refrigerant to the battery plate heat exchanger to prioritize cooling the battery pack 3. This design ensures that in extreme conditions of partial system failure, the limited cooling capacity can be prioritized to protect the safety of the core high-voltage component, the battery, avoiding thermal runaway due to battery overheating, and providing the vehicle with the ability to limp home until it can be safely brought to the repair shop.

[0034] In another technical solution, the two-position three-way valve inside the first thermal management unit 1 and / or the second thermal management unit 2 has the following switching states: In the first state, the low-temperature radiator is bypassed, allowing the coolant to circulate within the thermal management unit; In the second state, the low-temperature radiator is connected, allowing the coolant to flow through the low-temperature radiator for heat dissipation; Control module 4 is used to control the two-position three-way valve to switch between the first and second states according to the temperature of the coolant or the ambient temperature in low-temperature refrigeration mode. Specifically, the two-position three-way valve inside the system has two clearly defined switching states. The first state is the bypass state, in which the inlet of the two-position three-way valve is connected to the outlet of the bypass pipe connected to the low-temperature radiator, isolating the low-temperature radiator from the main coolant circuit. At this time, the coolant flows out of the plate heat exchanger without passing through the low-temperature radiator, directly to the water pump and PTC to complete the circulation. The second state is the connected state, in which the inlet of the two-position three-way valve is connected to the inlet leading to the low-temperature radiator, and the coolant is forced to be directed to the low-temperature radiator for heat dissipation. The control module 4 operates in the low-temperature refrigeration mode, and it dynamically controls the two-position three-way valve between these two states based on the coolant temperature or the ambient temperature. Switching between states, for example, when the ambient temperature is extremely low (e.g., -15℃) and the battery load is not large, the control module 4 can control the valve to remain in the connected state for natural air cooling. If the battery load increases sharply at this time, causing the coolant temperature to rise rapidly, but the ambient temperature still meets the low-temperature conditions, the control module 4 can temporarily switch the valve to the bypass state, allowing the coolant to flow through the plate heat exchanger and use the previously circulated low-temperature coolant for a period of self-circulation cooling without starting the compressor. This maximizes energy saving while meeting heat dissipation requirements. Through this dynamic switching between the two states, the potential of using natural cold sources in low-temperature environments is further explored, achieving more refined and energy-saving battery thermal management.

[0035] A control method for an integrated thermal management system for off-highway dump trucks is provided, comprising the following steps: S1. Obtain the ambient temperature; S2. Determine whether the ambient temperature is lower than the first preset temperature threshold. If so, enter the low-temperature cooling mode, shut down the compressors inside the first thermal management unit 1 and / or the second thermal management unit 2, and start the corresponding low-temperature radiator to cool the coolant and cool the battery pack 3. If not, enter the compressor cooling mode, start the compressors inside the first thermal management unit 1 and / or the second thermal management unit 2, and cool the coolant through the plate heat exchanger to cool the battery pack 3. S3. In low-temperature cooling mode, based on the temperature of the coolant or the ambient temperature, control the two-position three-way valve located upstream of the low-temperature radiator to switch between the first state of bypassing the low-temperature radiator and the second state of connecting the low-temperature radiator. S4. Set a hysteresis range according to the first preset temperature threshold. When the ambient temperature rises from below the first preset temperature threshold to above the second preset temperature threshold within the hysteresis range, control the exit of the low-temperature cooling mode. S5. When the conditions for motor waste heat recovery are met, control the switching of the first three-way valve 14 and the second three-way valve 15, connect the heating circuit 22 with the motor heat dissipation circuit 20, and allow the coolant from the drive motor 5 to flow through the heating core 9, using the waste heat of the drive motor 5 to heat the cab; when the indoor temperature exceeds the sum of the set temperature and the preset exit temperature difference threshold, or when the outlet temperature of the drive motor 5 is lower than the preset exit temperature threshold, control the exit of the motor waste heat recovery mode and control the PTC heater 10 to start for auxiliary heating. S6. Control signals are transmitted by electrically connecting the control integrated interface 17, which is provided on the housing of the first thermal management unit 1 or the second thermal management unit 2, to the wiring harness of the first thermal management unit 1 and / or the second thermal management unit 2. S7. When the first thermal management unit 1 and / or the second thermal management unit 2 malfunction, reduce the opening of the first electromagnetic expansion valve on the refrigerant pipeline leading to the air conditioning evaporator and increase the opening of the second electromagnetic expansion valve on the refrigerant pipeline leading to the solar panel heat exchanger. Specifically, the above content elaborates on the system's control methods. In step S1, after the entire system is started, the control module 4 reads the signal of the ambient temperature sensor 16 installed on the outside of the vehicle in real time through the CAN bus to obtain the current ambient temperature value. In the second step S2, the control module 4 compares the ambient temperature value with the first preset temperature threshold stored internally. The first preset temperature threshold can be set to -5℃. If the ambient temperature is lower than -5℃, the control module 4 enters the low-temperature cooling mode. In this mode, the control module 4 issues a command to shut down the compressors inside the first thermal management unit 1 and the second thermal management unit 2, and starts the electric fan of the corresponding unit. At the same time, it controls the two-position three-way valve to switch to the state of connecting to the low-temperature radiator. In this way, the coolant dissipates heat naturally in the low-temperature radiator through air flow, achieving low-energy cooling of the battery pack 3. Conversely, if the ambient temperature is not lower than -5℃, for example, 20℃, the compressor refrigeration mode is entered. The control module 4 starts the compressor and controls the two-position three-way valve to switch to the bypass low-temperature radiator state, so that the coolant flows through the plate heat exchanger and achieves efficient cooling through the compression refrigeration cycle. The third step, S3, involves fine-tuning the low-temperature cooling mode. Control module 4 operates in low-temperature cooling mode, dynamically controlling the state switching of the two-position three-way valve based on the coolant temperature or ambient temperature. When the coolant temperature is higher than the preset first temperature point (e.g., 15°C), the two-position three-way valve is controlled to be in the second state, so that the coolant flows through the low-temperature radiator and uses the ambient cold air for heat dissipation. When the coolant temperature drops below the preset second temperature point (e.g., 10°C), the two-position three-way valve is switched to the first state to bypass the low-temperature radiator. The coolant circulates only within the thermal management unit and battery pack 3 to avoid overcooling and save fan energy. When the battery load decreases and the coolant temperature rises again to the preset first temperature point, it switches back to the second state. Through this dynamic switching, in the low-temperature cooling mode, only the low-temperature radiator is used for air cooling, and the compressor does not need to be started to achieve stable control of the battery temperature. The fourth step, S4, is hysteresis range control. The control module 4 has a hysteresis range from -5℃ to -3℃. When the ambient temperature rises from -10℃ to -4℃, the system remains in low-temperature cooling mode. Only when the ambient temperature rises further and stabilizes above -3℃ will the control module 4 exit the low-temperature cooling mode and may proceed to the next judgment logic. Step S5 is the motor waste heat recovery control. When the two conditions of "motor body temperature exceeds the limit" and "cabin has a stable heating demand" are met, the control module 4 controls the first three-way valve 14 and the second three-way valve 15 to switch so that the water output of the drive motor 5 flows directly through the heater core 9 to heat the cab. When the indoor temperature reaches the standard or the motor water temperature is too low, this mode is exited and the PTC heater 10 is automatically started for auxiliary heating. Step S6 involves control integration. All control command signals, including the start and stop of the compressor, the power regulation of the PTC, the speed control of the fan and water pump, and the opening control of the solenoid valve, are communicated at high speed with the vehicle controller or thermal management domain controller through the control integration interface 17 set on the thermal management unit housing via a trunk wiring harness to achieve highly integrated control. Step S7 is the fault handling logic. When the control module 4 detects a serious fault in a thermal management unit or its compressor, it will immediately reduce the opening of the first electromagnetic expansion valve leading to the air conditioning evaporator, for example, from 50% to 10%, and at the same time open the second electromagnetic expansion valve leading to the solar panel heat exchanger to the maximum, for example, 100%, to ensure that the valuable cooling capacity can be used to cool the battery first and prevent battery thermal runaway. Through the aforementioned series of interconnected control steps, this invention provides an intelligent and refined thermal management control method. This method can automatically select the optimal energy consumption operating mode based on information such as ambient temperature, coolant temperature, and vehicle operating conditions. It achieves global optimization management of the battery, motor, electronic control system, and cab heating, ultimately achieving the technical effects of ensuring system safety under extreme operating conditions, maximizing energy utilization efficiency under normal operating conditions, and providing safety redundancy in the event of partial failures.

[0036] A non-highway dump truck is provided, including a non-highway dump truck thermal management integrated system. Specifically, the non-highway dump truck's core power system is pure electric drive or hybrid drive. The non-highway dump truck includes a complete non-highway dump truck thermal management integrated system, which is integratedly arranged behind the non-highway dump truck's frame or cab. A first thermal management unit 1 and a second thermal management unit 2 can be mounted side by side on a dedicated bracket, which is fixed between the longitudinal beams of the frame. The battery pack 3 can be arranged in the battery compartments on both sides of the frame, and is cooled by a first cooling system. The liquid circuit 18 and the second coolant circuit 19 are connected to the thermal management unit. The control module 4 can be integrated into the vehicle controller and connected to each actuator through high-voltage and low-voltage wiring harnesses. This application of a high-efficiency, intelligent and integrated thermal management system to off-highway dump trucks enables the vehicle to accurately cope with the challenges of high load, high temperature and seasonal temperature difference in harsh environments such as mines and construction sites. It significantly improves the vehicle's range, the life of the power battery and the safety and reliability of the vehicle in harsh environments, and has extremely high commercial value and economic benefits.

[0037] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. Off-highway dump truck thermal management integrated system, characterized in that, include: The first thermal management unit integrates the first compressor and the first low-temperature radiator. The second thermal management unit integrates a second compressor and a second low-temperature radiator. The battery pack has a first coolant inlet, a second coolant inlet, a first coolant outlet, and a second coolant outlet; The first coolant circuit is connected between the coolant inlet and outlet of the first thermal management unit and the first coolant inlet and the first coolant outlet of the battery pack, forming a first independent circulation branch. The second coolant circuit is connected between the coolant inlet and outlet of the second thermal management unit and the second coolant inlet and the second coolant outlet of the battery pack, forming a second independent circulation branch; The control module is used to acquire the ambient temperature; When the ambient temperature is lower than a first preset temperature threshold, the first thermal management unit and / or the second thermal management unit are controlled to enter a low-temperature cooling mode. In the low-temperature cooling mode, the first compressor and / or the second compressor are turned off, and the first low-temperature radiator and / or the second low-temperature radiator are started to cool the coolant and cool the battery pack. When the ambient temperature is not lower than the first preset temperature threshold, the first thermal management unit and / or the second thermal management unit are controlled to enter the compressor cooling mode. In the compressor cooling mode, the first compressor and / or the second compressor are started, and the coolant is cooled through the plate heat exchanger to cool the battery pack.

2. The off-highway dump truck thermal management integrated system of claim 1, wherein, Also includes: Drive motor; An electric motor cooling circuit includes an electric motor radiator, wherein the inlet of the electric motor radiator is connected to the outlet of the drive motor via a first water pump, and the outlet of the electric motor radiator is connected to the inlet of the drive motor. An electronically controlled heat dissipation circuit includes an electronically controlled radiator, wherein the inlet of the electronically controlled radiator is connected to the outlet of the motor controller via a second water pump, and the outlet of the electronically controlled radiator is connected to the inlet of the motor controller. The heating circuit includes a heating core, the outlet of which is selectively connected to the inlet of the motor radiator via a second three-way valve. The inlet of the second three-way valve is connected to the outlet of the heating core, one outlet of the second three-way valve is connected to the inlet of the motor radiator, and the other outlet of the second three-way valve is connected to the inlet of the PTC heater. The control module is also used to control the connection between the heating circuit and the motor heat dissipation circuit when the motor waste heat recovery conditions are met. The coolant from the drive motor flows through the heating core, and the waste heat of the drive motor is used to heat the cab, thus entering the motor waste heat recovery mode. Furthermore, the control module is also used to control the exit of the motor waste heat recovery mode and control the PTC heater to start for auxiliary heating when the indoor temperature exceeds the sum of the set temperature and the preset exit temperature difference threshold, or when the outlet temperature of the drive motor is lower than the preset exit temperature threshold.

3. The off-highway dump truck thermal management integrated system of claim 1, wherein, The first thermal management unit and / or the second thermal management unit further include a two-position three-way valve, which is located upstream of the cryogenic radiator and is used for: In the low-temperature cooling mode, the coolant is directed to the low-temperature radiator; The low-temperature radiator is bypassed in the compressor cooling mode.

4. The off-highway dump truck thermal management integrated system of claim 1, wherein, The control module further includes a hysteresis interval unit, which is used to set a hysteresis interval according to the first preset temperature threshold. The hysteresis interval is used to control the ambient temperature threshold when the low temperature cooling mode exits to be higher than the first preset temperature threshold.

5. The off-highway dump truck thermal management integrated system of claim 2, wherein, The heat dissipation power of the motor radiator is less than that of the electronic control radiator.

6. The off-highway dump truck thermal management integrated system of claim 1, wherein, It also includes a control integration interface, which is disposed on the housing of the first thermal management unit or the second thermal management unit, and the control integration interface is electrically connected to the wiring harness of the first thermal management unit and / or the second thermal management unit.

7. The off-highway dump truck thermal management integrated system of claim 1, wherein, The refrigerant circuit of the first thermal management unit and / or the second thermal management unit includes: The first electromagnetic expansion valve is installed on the refrigerant pipeline leading to the air conditioner evaporator. The second electromagnetic expansion valve is installed on the refrigerant pipeline leading to the solar panel heat exchanger. The control module is also used to reduce the opening of the first electromagnetic expansion valve and increase the opening of the second electromagnetic expansion valve when the first thermal management unit and / or the second thermal management unit malfunctions.

8. The off-highway dump truck thermal management integrated system of claim 3, wherein, The two-position three-way valve inside the first thermal management unit and / or the second thermal management unit has the following switching states: In the first state, the low-temperature radiator is bypassed, allowing the coolant to circulate within the thermal management unit; In the second state, the low-temperature radiator is connected, allowing the coolant to flow through the low-temperature radiator for heat dissipation; The control module is used to control the two-position three-way valve to switch between the first state and the second state according to the temperature of the coolant or the ambient temperature in the low-temperature refrigeration mode.

9. The control method of the off-highway dump truck thermal management integrated system according to any one of claims 1-8, wherein, Includes the following steps: S1. Obtain the ambient temperature; S2. Determine whether the ambient temperature is lower than the first preset temperature threshold. If yes, enter the low-temperature cooling mode, shut down the compressor inside the first thermal management unit and / or the second thermal management unit, and start the corresponding low-temperature radiator to cool the coolant and cool the battery pack. If no, enter the compressor cooling mode, start the compressor inside the first thermal management unit and / or the second thermal management unit, and cool the coolant through the plate heat exchanger to cool the battery pack. S3. In the low-temperature refrigeration mode, according to the temperature of the coolant or the ambient temperature, the two-position three-way valve located upstream of the low-temperature radiator is controlled to switch between a first state that bypasses the low-temperature radiator and a second state that connects to the low-temperature radiator. S4. Set a hysteresis range according to the first preset temperature threshold. When the ambient temperature rises from below the first preset temperature threshold to above the second preset temperature threshold within the hysteresis range, control the exit of the low-temperature cooling mode. S5. When the conditions for motor waste heat recovery are met, control the switching of the first three-way valve and the second three-way valve, connect the heating circuit and the motor heat dissipation circuit, and the coolant from the drive motor flows through the heating core to heat the cab using the waste heat of the drive motor, thus entering the motor waste heat recovery mode; when the indoor temperature exceeds the sum of the set temperature and the preset exit temperature difference threshold, or when the outlet temperature of the drive motor is lower than the preset exit temperature threshold, control the exit of the motor waste heat recovery mode and control the PTC heater to start for auxiliary heating. S6. Control signals are transmitted by electrically connecting the control integration interface provided on the housing of the first thermal management unit or the second thermal management unit to the wiring harness of the first thermal management unit and / or the second thermal management unit. S7. When the first thermal management unit and / or the second thermal management unit malfunctions, the opening of the first electromagnetic expansion valve on the refrigerant pipeline leading to the air conditioning evaporator is reduced, and the opening of the second electromagnetic expansion valve on the refrigerant pipeline leading to the solar panel heat exchanger is increased.

10. Off-highway dump truck, characterized in that Including the off-highway dump truck thermal management integrated system as described in any one of claims 1 to 8.

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