Quick-charging pile side active cooling system based on secondary loop and control method of quick-charging pile side active cooling system

Abstract

The invention discloses a quick charging pile side active cooling system based on a secondary loop and a control method thereof, and belongs to the technical field of new energy automobile heat management and multi-heat-source integration. According to the system, the charging pile connector is connected with the first cooling liquid loop of the charging pile heat management system and the second cooling liquid loop of the vehicle-mounted heat management system, a large amount of heat generated by a battery during quick charging is transferred to the charging pile heat management system to be dissipated, the vehicle-mounted heat management system continues to work, and the temperature and humidity requirements of other parts of the system are met. According to the system, efficient and rapid cooling of the battery can be achieved during rapid charging, the size and weight of the vehicle-mounted thermal management system can be effectively optimized, and the overall system cost is reduced. According to the system, a reasonable control strategy and method are adopted, temperature control target response of the charging pile heat management system and the vehicle-mounted heat management system is achieved through multi-PID coupling control, and therefore the safety of a battery during fast charging is guaranteed, meanwhile, the heat management requirement of a compartment is met, and the efficiency and reliability of the system are improved.

Description

Technical Field

[0001] This invention belongs to the field of vehicle thermal management technology, specifically relating to an active cooling system for fast charging piles based on a secondary circuit and its control method. Background Technology

[0003] Currently, fast charging and supercharging technologies (top-tier fast charging that relies on technologies such as an 800V high-voltage platform to achieve extremely rapid energy replenishment) are continuously developing. In the future, at charging rates of 5C and above, batteries may generate an average heat output exceeding 20kW during charging, even reaching five times the heat generated during discharging. Under such circumstances, the battery pack temperature may rapidly rise above 50°C, seriously affecting battery safety and thus placing higher demands on the performance of the vehicle's thermal management system. If the thermal management needs of fast charging in the future rely entirely on the vehicle's thermal management system, under normal driving conditions, approximately 60% of the vehicle's thermal management system capacity will be idle, not only causing redundancy in system weight and volume but also reducing the overall vehicle's energy efficiency and performance.

[0004] As power supply equipment for electric vehicles, the thermal management requirements of charging piles during fast charging have become a widespread concern in academia and industry. Similar to vehicle thermal management, the thermal management of charging piles also includes methods such as air cooling, liquid cooling, and the use of phase change materials to achieve precise temperature control of the charging pile and charging cables. Among these, liquid cooling offers superior thermal management performance and has become the method currently used in fast charging piles, providing a new approach to comprehensive thermal management in fast charging scenarios.

[0005] Therefore, how to efficiently manage battery heat in fast charging scenarios and avoid system expansion and increased costs caused by redundant design of the vehicle thermal management system has become a key issue that urgently needs to be addressed. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a fast charging pile side active cooling system and its control method based on a secondary circuit, so as to solve the problem of system expansion and increased cost caused by redundant design of the vehicle thermal management system in the charging scenario in the prior art. To achieve the above objectives, the present invention employs the following technical solution: An active cooling system for fast charging piles based on a secondary circuit includes: A charging pile thermal management system is installed on the side of the charging pile and includes a first coolant circuit and a first refrigerant circuit. The first refrigerant circuit exchanges heat with the first coolant circuit through a first evaporator. The vehicle-mounted thermal management system is installed on the vehicle side and includes a second coolant circuit and a second refrigerant circuit. The second refrigerant circuit exchanges heat with the second coolant circuit through a second evaporator. Fast charging interface, including piping for coolant flow; The pipeline of the first coolant circuit is operably connected to the pipeline of the second coolant circuit through the fast charging interface. The first coolant circuit includes a first water pump connected to the fast charging interface, the first water pump being connected to the coolant side of the first evaporator, and the coolant side of the first evaporator being connected to the fast charging interface; The first refrigerant circuit includes a first compressor, a first radiator, a high-pressure pipeline of a first regenerator, a refrigerant side of a first evaporator, a first gas-liquid separator, and a low-pressure pipeline of the first regenerator connected in sequence. The second refrigerant circuit includes a second compressor, a second radiator, a high-pressure pipeline of a second regenerator, a refrigerant side of a second evaporator, a second gas-liquid separator, and a low-pressure pipeline of the second regenerator connected in sequence. The second coolant circuit includes a nine-way valve, a first three-way valve, a second three-way valve, and a shut-off valve that are controllably connected to the nine-way valve; it also includes a motor radiator, an outdoor heat exchanger, an indoor first heat exchanger, an indoor second heat exchanger, and a battery heat exchanger that are controllably connected to the nine-way valve.

[0007] A further improvement of the present invention is that: Preferably, when the system operates in battery cooling mode during fast charging, the first three-way valve guides the high-temperature coolant flowing from the outlet of the second radiator to the nine-way valve; the nine-way valve guides the high-temperature coolant from the first three-way valve to the outdoor heat exchanger and guides the coolant from the battery heat exchanger to the second water pump; the second three-way valve guides the low-temperature coolant flowing from the outlet of the second evaporator to the nine-way valve; the nine-way valve also guides the low-temperature coolant from the second three-way valve to the battery heat exchanger; and the shut-off valve is closed.

[0008] Preferably, when the system is operating in the passenger cabin cooling mode during fast charging, the first three-way valve guides the high-temperature coolant flowing from the outlet of the second radiator to the nine-way valve; the nine-way valve guides the high-temperature coolant from the first three-way valve to the outdoor heat exchanger; the second three-way valve guides the low-temperature coolant flowing from the outlet of the second evaporator to the indoor second heat exchanger; and the shut-off valve is closed.

[0009] Preferably, when the system is operating in the passenger compartment heating mode during fast charging, the first three-way valve guides the high-temperature coolant flowing from the outlet of the second radiator to the indoor first heat exchanger; the second three-way valve guides the low-temperature coolant flowing from the outlet of the second evaporator to the nine-way valve; the nine-way valve guides the low-temperature coolant from the second three-way valve to the outdoor heat exchanger; and the shut-off valve is closed.

[0010] Preferably, when the system operates in the passenger cabin cooling and dehumidification mode during fast charging, the first three-way valve simultaneously guides the high-temperature coolant flowing from the outlet of the second radiator to the first indoor heat exchanger and the nine-way valve; the nine-way valve guides a portion of the high-temperature coolant from the first three-way valve to the outdoor heat exchanger; the second three-way valve guides the low-temperature coolant flowing from the outlet of the second evaporator to the second indoor heat exchanger; and the shut-off valve is closed.

[0011] Preferably, when the system operates in the passenger compartment heating and defogging mode during fast charging, the first three-way valve guides the high-temperature coolant flowing from the outlet of the second radiator to the first indoor heat exchanger; the second three-way valve simultaneously guides the low-temperature coolant flowing from the outlet of the second evaporator to the second indoor heat exchanger and the nine-way valve; the nine-way valve guides a portion of the low-temperature coolant from the second three-way valve to the outdoor heat exchanger; and the shut-off valve is closed.

[0012] A control method for the above-mentioned active cooling system for fast charging piles based on a secondary loop includes the following steps: Real-time monitoring of battery temperature to determine whether the vehicle has entered fast charging mode; When entering fast charging mode, the first coolant circuit and the second coolant circuit are connected through the fast charging interface, and the charging pile thermal management system is activated. A multi-PID coupled control strategy is adopted to control the charging pile thermal management system and the vehicle thermal management system respectively, wherein: The control of the charging pile thermal management system includes at least the following: adjusting the speed of the first compressor by a first PID controller based on the difference between the outlet water temperature of the first evaporator and the first target temperature; adjusting the opening of the first electronic expansion valve by a second PID controller based on the difference between the suction superheat of the first compressor and the second target superheat; and adjusting the speed of the first water pump by a third PID controller based on the difference between the battery temperature and the third target temperature. The control of the vehicle thermal management system includes at least the following: according to the refrigerant type of the second refrigerant circuit, selecting the difference between the discharge pressure or suction superheat of the second compressor and the corresponding target value, and adjusting the opening of the second electronic expansion valve through the fourth PID controller; and adjusting the speed of the second compressor through the fifth PID controller based on the difference between the outlet water temperature of the second evaporator and the fourth target temperature.

[0013] Preferably, the control of the vehicle thermal management system adaptively selects control variables based on the refrigerant type of the second refrigerant circuit. When CO2 is used, the fourth PID controller adjusts based on the discharge pressure of the second compressor; when R290 is used, the fourth PID controller adjusts based on the suction superheat of the second compressor.

[0014] Preferably, the control method further includes control of battery temperature and passenger compartment thermal management: based on the difference between battery temperature and target battery temperature, the speed of the fourth water pump is adjusted by the eighth PID controller; based on the difference between passenger compartment air supply temperature or cabin temperature and the corresponding target value, the speed of the second water pump is adjusted by the sixth PID controller, and the speed of the indoor fan is adjusted by the seventh PID controller.

[0015] Preferably, during the control process, the nine-way valve, the first three-way valve, the second three-way valve, and the shut-off valve are switched to the configuration state of the corresponding control mode.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention discloses an active cooling system for fast-charging piles based on a secondary loop. By connecting and circulating the cooling loops of the charging pile's thermal management system and the vehicle's thermal management system, the significant heat dissipation demand during fast charging of electric vehicles is transferred to the charging pile's thermal management system, ensuring efficient and rapid cooling of the battery during fast charging. This reduces the extreme load on the vehicle's thermal management system, effectively optimizing its size and weight, lowering overall system costs, and making components such as the compressor operate more efficiently. Furthermore, the secondary loop architecture of the vehicle's thermal management system significantly simplifies the complexity of the refrigerant circuit, improves system safety, and facilitates modular integration of the thermal management system, optimizing space utilization. It possesses good versatility and universality, suitable for natural refrigerants such as CO2 and R290, to adapt to different refrigerant alternative requirements.

[0017] This invention discloses a control method for an active cooling system on the fast charging pile side based on a secondary loop. In the charging pile's heat pipe system, the outlet water temperature, superheat, and battery temperature are effectively controlled by adjusting the compressor speed, electronic expansion valve opening, and water pump speed on the charging pile side. This ensures the safety of the charging cable and battery during charging and improves system efficiency and reliability. Furthermore, in different modes of the vehicle thermal management system, the exhaust pressure / superheat, outlet water temperature, supply air temperature, passenger compartment temperature, and battery temperature are optimized and rapidly responded to by adjusting the electronic expansion valve opening, compressor speed, water pump speed, and fan speed. This ensures passenger comfort and battery safety, and maximizes the system's efficient operation. Attached Figure Description

[0018] Figure 1This is a system diagram of active cooling for fast charging at the charging pile side based on the secondary circuit of the vehicle's thermal management. Figure 2 This is a control strategy diagram for active cooling of fast charging piles based on the secondary loop of vehicle thermal management; Figure 3 System flowchart for battery cooling mode during fast charging; Figure 4 System flowchart for the passenger cabin cooling mode during fast charging; Figure 5 System flowchart for passenger cabin heating mode during fast charging; Figure 6 System flowchart for the passenger cabin cooling and dehumidification mode during fast charging; Figure 7 System flowchart for passenger compartment heating and defogging mode during fast charging; In the diagram, 101 is the charging pile thermal management system; 102 is the vehicle-mounted thermal management system; 1 is the first compressor; 2 is the first radiator; 3 is the first regenerator; 4 is the first electronic expansion valve; 5 is the first evaporator; 6 is the first gas-liquid separator; 7 is the first bypass valve; 8 is the first fan; 9 is the first water pump; 11 is the second compressor; 12 is the second radiator; 13 is the second regenerator; 14 is the second electronic expansion valve; 15 is the second evaporator; 16 is the second gas-liquid separator; 17 is the second bypass valve; 18 is the hot gas bypass valve; 21 is the outdoor heat exchanger; 22 is the indoor... 23. Indoor second heat exchanger; 24. Outdoor fan; 25. Indoor fan; 26. Battery heat exchanger; 27. Motor radiator; 28. First WPTC; 29. ​​Second WPTC; 31. Second water pump; 32. Third water pump; 33. Fourth water pump; 34. Fifth water pump; 35. Nine-way valve; 36. First three-way valve; 37. Second three-way valve; 38. Shut-off valve; 201. First interface three-way valve; 202. Second interface three-way valve; 203. Third interface three-way valve; 204. Fourth interface three-way valve; 205. Interface. Detailed Implementation

[0019] Hereinafter, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," "third," or "fourth" may explicitly or implicitly include one or more of that feature.

[0020] The synchronization method provided in this application can be applied to mobile phones, tablets, wearable devices, in-vehicle devices, augmented reality (AR) / virtual reality (VR) devices, laptops, and ultra-mobile personal computers. In this application, the specific type of terminal device is not limited to terminal devices such as mobile personal computers (UMPCs), netbooks, and personal digital assistants (PDAs).

[0021] It should be noted that the terms "first," "second," etc., used in the specification and drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] The present invention will now be described in further detail with reference to the accompanying drawings: Please see Figure 1 As shown, the present invention provides an active cooling system for fast charging piles based on a secondary circuit, including a charging pile thermal management system and an on-board thermal management system.

[0023] The charging pile thermal management 101 system includes: a first compressor 1, a first radiator 2, a first regenerator 3, a first electronic expansion valve 4, a first evaporator 5, a first gas-liquid separator 6, a first bypass valve 7, a first fan 8, and a first water pump 9.

[0024] The vehicle-mounted thermal management system 102 includes: a second compressor 11, a second radiator 12, a second regenerator 13, a second electronic expansion valve 14, a second evaporator 15, a second gas-liquid separator 16, a second bypass valve 17, a hot gas bypass valve 18, an outdoor heat exchanger 21, an indoor first heat exchanger 22, an indoor second heat exchanger 23, an outdoor fan 24, an indoor fan 25, a battery heat exchanger 26, a motor radiator 27, a first WPTC 28 (Water Positive Temperature Coefficient heater), a second WPTC 29, a second water pump 31, a third water pump 32, a fourth water pump 33, a fifth water pump 34, a nine-way valve 35, a first three-way valve 36, a second three-way valve 37, and a shut-off valve 38.

[0025] The indoor first heat exchanger 22, indoor second heat exchanger 23 and indoor fan 25 are located in the air conditioning unit. By switching between the indoor first heat exchanger 22 and indoor second heat exchanger 23, the occupant cabin can be cooled or heated in different modes.

[0026] In addition, it also includes a first interface three-way valve 201, a second interface three-way valve 202, a third interface three-way valve 203, and a fourth interface three-way valve 204.

[0027] The charging pile thermal management system and the vehicle thermal management system are connected via interface 205; the nine-way valve has nine ports: A, B, C, D, E, F, G, H, and I; the three-way switching valve has three ports: a, b, and c.

[0028] In the first refrigerant circuit of the charging pile thermal management system, the exhaust port of the first compressor 1 is connected to the inlet of the first radiator 2 via a pipeline. High-temperature, high-pressure refrigerant exchanges heat with air via the first radiator 2. The outlet of the first radiator 2 is connected to the high-pressure inlet of the first regenerator 3 via a pipeline. The high-pressure outlet of the first regenerator 3 is connected to the inlet of the first electronic expansion valve 4 via a pipeline. The outlet of the first electronic expansion valve 4 is connected to the refrigerant-side inlet of the first evaporator 5 via a pipeline. The throttled, low-pressure refrigerant exchanges heat with water via the first evaporator 5, causing the water temperature to drop. The refrigerant-side outlet of the first evaporator 5 is connected to the inlet of the first gas-liquid separator 6 via a pipeline. The outlet of the first gas-liquid separator 6 is connected to the inlet of the first bypass valve 7 and the low-pressure inlet of the first regenerator 3 via pipelines. The outlet of the first bypass valve 7 and the low-pressure outlet of the first regenerator 3 are both connected to the inlet of the first compressor 1 via pipelines, thus forming a complete circuit.

[0029] The refrigerant used in the thermal management system of the charging pile is R290.

[0030] In the first coolant circuit of the charging pile thermal management system, the outlet of the first water pump 9 is connected to the coolant inlet of the first evaporator 5 via a pipeline. The coolant outlet of the first evaporator 5 is connected to port a of the second interface three-way valve 202. Port b of the second interface three-way valve 202 is connected to port b of the first interface three-way valve 201. Port a of the first interface three-way valve 201 is connected to the inlet of the first water pump 9. Port c of the first interface three-way valve 201 is connected to the outlet of interface 205. Port c of the second interface three-way valve 202 is connected to the inlet of interface 205. Interface 205 is connected to port a of the third interface three-way valve 203 and the fourth interface three-way valve 204, thereby realizing the connection of the cooling water circuit.

[0031] The vehicle-mounted thermal management system employs a secondary loop. In the second refrigerant loop, the exhaust port of the second compressor 11 is connected to the inlet of the second radiator 12 via a pipeline. High-temperature, high-pressure refrigerant exchanges heat with the water circuit via the second radiator 12, causing the water temperature to rise. The outlet of the second radiator 12 is connected to the high-pressure inlet of the second regenerator 13 via a pipeline. The high-pressure outlet of the second regenerator 13 is connected to the inlet of the second electronic expansion valve 14 via a pipeline. The outlet of the second electronic expansion valve 14 is connected to the inlet of the second evaporator 15 via a pipeline. The throttled, low-pressure refrigerant exchanges heat with the water circuit via the second evaporator 15, causing the water temperature to drop. The outlet of the second evaporator 15 is connected to the inlet of the second gas-liquid separator 16 via a pipeline. In the second gas-liquid separator 16, the refrigerant is separated into gaseous and liquid states. The outlet of the second gas-liquid separator 16 is connected to the inlet of the second bypass valve 17 via a pipeline, and simultaneously connected to the second inlet of the second regenerator 13 via another pipeline. The outlet of the second bypass valve 17 is connected to the inlet of the second compressor 11 through a pipeline. Depending on the operating conditions, the refrigerant bypasses the second regenerator 13 through the second bypass valve 17 and returns directly to the second compressor 11, or it connects to the second compressor 11 through the second outlet of the second regenerator 13, thus forming a complete circuit.

[0032] The refrigerant used in the vehicle thermal management system is R290 or CO2.

[0033] In the second coolant circuit of the vehicle thermal management system, the flow paths of high-temperature and low-temperature coolant are regulated by a nine-way valve 35, a first three-way valve 36, a second three-way valve 37, and a shut-off valve 38, enabling multiple operating modes, including simultaneous heating of the passenger compartment and battery, heating of the passenger compartment and cooling of the battery, and dehumidification. The flexible configuration of this system can optimize the flow paths of refrigerant and water under different operating conditions, ensuring the temperature and humidity of all major components to meet the dynamic requirements of the vehicle environment.

[0034] The charging pile thermal management system 101 and the vehicle thermal management system 102 use the same coolant.

[0035] Please see Figure 2 As shown, this invention provides a control method for an active cooling system on the fast charging pile side based on a secondary loop. The specific control flow is as follows: The battery temperature is monitored in real time. When it is determined that the fast charging state has been entered, the charging pile thermal management system and the vehicle thermal management system are activated, and multi-PID coupled control is performed. During this process, the determination of entering the fast charging state is triggered by the communication protocol between the vehicle and the charging pile, pre-setting the conditions for both the vehicle and the charging pile.

[0036] The specific logic is as follows: the charging pile thermal management system includes evaporator outlet water temperature control, superheat control, and battery temperature control. The data that needs to be recorded includes: recording the suction superheat T of the first compressor 1. super1 The outlet water temperature T of the first evaporator 5 w1 Battery temperature T bat Ambient temperature T amb and the refrigerant side outlet temperature T of the evaporator ref1,out Furthermore, the target suction superheat of the first compressor 1 is set to T. super1,t The target outlet water temperature of the first evaporator 5 is set to T. w1,set Set the target battery temperature to T. bat,t PID1 is the first PID controller, controlling the evaporator outlet water temperature. Its input is the difference between the evaporator outlet water temperature and the set target, and its output is the rotational speed of the first compressor 1. PID2 is the second PID controller, controlling the superheat of the first compressor 1's suction air. Its input is the difference between the superheat and the set target, and its output is the opening degree of the first electronic expansion valve 4. PID3 is the third PID controller, controlling the battery temperature. Its input is the difference between the battery temperature and the set target, and its output is the rotational speed (i.e., water flow rate) of the first water pump 9. When the temperature of all controlled objects reaches the set value, the system enters a stable state. Subsequently, in the non-stop state, i.e., during the operation of the charging pile thermal management system, the system continuously monitors the battery status to determine whether it needs to remain in fast charging mode and continuously adjusts the process. If the charging pile thermal management system shuts down, the entire fast charging logic control process ends.

[0037] The specific logic of the vehicle thermal management system is as follows: it determines whether the second compressor 11 of the system is started and whether the battery has an emergency thermal management requirement (whether the temperature exceeds the set emergency thermal management temperature). If the battery has an emergency thermal management requirement, the battery safety is the primary goal, and the comfort requirements of the passenger compartment are not considered. If the battery does not have an emergency thermal management requirement, it determines whether the passenger compartment has a thermal management requirement.

[0038] The vehicle thermal management system includes exhaust pressure and superheat control, evaporator outlet water temperature control, air supply temperature control, passenger compartment temperature control, and battery temperature control. The suction superheat T of the second compressor 11 is recorded. super2The outlet water temperature T of the second evaporator 15 w2 Battery temperature T bat Battery charging start temperature T bats Ambient temperature T amb evaporator refrigerant side outlet temperature T ref2,out Indoor heat exchanger inlet air temperature T airin Operating mode. Additionally, the target suction superheat of the second compressor 11 is set to T. super2,t Or target exhaust pressure P dis,t The target outlet water temperature of the second evaporator 15 is set to T. w2,set Set the target air supply temperature to T. s,set Set the target temperature of the carriage to T c,set Set the target battery temperature to T. bat,t PID4 is the fourth PID controller, acting as the superheat controller for the suction air of the second compressor 11. Its input is the difference between the discharge pressure and the set target, or the superheat and the set target. Its output is the opening degree of the second electronic expansion valve 14. PID5 is the fifth PID controller, acting as the evaporator outlet water temperature controller. Its input is the difference between the evaporator outlet water temperature and the set target. Its output is the speed of the second compressor 11. PID6 is the sixth PID controller, acting as the supply air temperature controller. Its input is the difference between the supply air temperature and the set target. Its output is the speed of the second water pump 31. PID7 is the seventh PID controller, acting as the passenger compartment temperature controller. Its input is the difference between the passenger compartment temperature and the set target. Its output is the speed of the indoor fan 25, i.e., the airflow. PID8 is the eighth PID controller, acting as the battery temperature controller. Its input is the difference between the battery temperature and the set target. Its output is the speed of the fourth water pump 33, i.e., the water flow rate.

[0039] In different control modes, the vehicle thermal management system enters a stable state when the temperature of all controlled objects reaches the set value. Subsequently, without shutting down, the system continuously monitors the battery status to determine whether fast charging mode is still needed and continues to adjust the process. If the vehicle thermal management system shuts down (stops working), the entire fast charging logic control process ends.

[0040] If the refrigerant is CO2, the controlled quantity is the discharge pressure; if the refrigerant is R290, the controlled quantity is the suction superheat.

[0041] When there is a difference between the target value and the set value, the corresponding actuator is controlled by PID control to make the difference between the target value and the set value less than the allowable error.

[0042] In the thermal management system of the charging pile, the outlet water temperature T of the first evaporator 5 is... w1The speed of the first compressor 1 is adjusted and controlled by the first PID controller to maintain the outlet water temperature of the first evaporator 5 at the set value T. w1,set Its expression is: T w,t =f(T bat ); The suction superheat T of the first compressor 1 super1 The opening degree of the first electronic expansion valve 4 is controlled by the second PID controller. Adjusting the opening degree of the first electronic expansion valve 4 maintains the suction superheat of the first compressor 1 at the set value T. super1,t Inhalation superheat T super1,t From ambient temperature T amb and evaporator refrigerant outlet temperature T ref1,out It is determined that its expression is: T super,t =f(T amb ,T ref,out ); Battery temperature T bat The rotational speed of the first water pump 9 is regulated by a third PID controller to maintain the battery temperature at a set value T. bat,t Its expression is: T bat,t =f(T amb ,T bats ).

[0043] In the vehicle thermal management system, the suction superheat T of the second compressor 11 of R290 super2 The opening degree of the second electronic expansion valve 14 is controlled by the fourth PID controller. Adjusting the opening degree of the second electronic expansion valve 14 maintains the suction superheat of the second compressor 11 at the set value T. super,t Inhalation superheat T super,t From ambient temperature T amb and evaporator refrigerant outlet temperature T ref,out It is determined that its expression is: T super,t =f(T amb ,T ref,out ).

[0044] Alternatively, the discharge pressure P of the second CO2 compressor 11 dis The opening degree of the second electronic expansion valve 14 is controlled by PID regulation to maintain the exhaust pressure at the set value P. dis,t Due to ambient temperature T amb and evaporator refrigerant outlet temperature T ref,out It is determined that its expression is: P dis,t =f(T amb ,T ref,out ).

[0045] The outlet water temperature T of the second evaporator 15 w2 The rotational speed of the second compressor 11 is regulated by the fifth PID controller to maintain the outlet water temperature of the second evaporator 15 at the set value T. w2,set Its expression is: T w,t =f(T amb , mode).

[0046] Carriage air supply temperature T s The rotational speed of the second water pump 31 is regulated by the sixth PID controller to maintain the air supply in the carriage at the set value T. s,t Its expression is: T s,t =f(T amb ,T air,in ).

[0047] Carriage temperature T c The speed of the indoor fan 25 is regulated by the seventh PID controller to maintain the cabin temperature at the set value T. c,t Its expression is: T c,t =f(T amb ).

[0048] Battery temperature T bat The rotational speed of the fourth water pump 33 is regulated by the eighth PID controller to maintain the battery temperature at the set value T. bat,t Its expression is: T bat,t =f(T amb ,T bats ).

[0049] During fast charging, the specific PID controller used by the vehicle's thermal management system will vary depending on the specific operating state; while the charging pile's thermal management system uses three PID controllers simultaneously to work together to maintain system stability.

[0050] For different control modes, the present invention provides some specific embodiments: When the battery fast charging mode is entered, ports A and C of the first three-way valve 201, the second three-way valve 202, the third three-way valve 203, and the fourth three-way valve 204 are connected, thus connecting the first coolant circuit of the charging pile thermal management system and the second coolant circuit of the vehicle thermal management system. At this time, the low-temperature coolant that has exchanged heat with the first evaporator 4 in the charging pile thermal management system flows into the battery heat exchanger under the action of the first water pump 9, absorbing the battery's heat and ensuring the battery's safety during fast charging.

[0051] Please see Figure 3 As shown, this invention provides an active cooling system for fast charging piles based on a secondary circuit. During fast charging, the battery cooling mode is activated when the battery temperature exceeds a set emergency safety threshold temperature. The charging pile-side thermal management system and the vehicle-mounted thermal management system work together to manage the battery's thermal performance. The charging pile-side thermal management system operates as follows: Figure 2 The process shown is controlled by the above-mentioned charging pile thermal management system. The C port of the nine-way valve 35 is connected to the G port, the E port is connected to the F port, the B port is connected to the H port, and the A port is connected to the I port. The a port of the first three-way valve 36 is connected to the c port, the a port of the second three-way valve 37 is connected to the c port, and the shut-off valve 38 is closed. The high-temperature, high-pressure refrigerant from the outlet of the second compressor 11 flows to the second radiator 12 and coolant for heat exchange. After releasing heat, the refrigerant flows through the second regenerator 13 and is throttled to a low-temperature, low-pressure state by the second electronic expansion valve 14. Then, the refrigerant flows into the second evaporator 15 and coolant for heat exchange. After absorbing heat, the refrigerant flows sequentially through the second gas-liquid separator 16 and the low-pressure side of the second regenerator 13, and returns to the second compressor 11. The high-temperature coolant after exchanging heat with the second radiator 12, driven by the second water pump 31, flows sequentially through the first three-way valve 36 and the nine-way valve 35, and enters the outdoor heat exchanger 21 to release heat to the ambient air. After releasing heat, the coolant can be judged according to the motor temperature whether it needs to flow through the motor to absorb heat, and then flows back to the second water pump 31, repeating the cycle. After exchanging heat with the evaporator 5, the low-temperature coolant, driven by the third water pump 32, flows through the second three-way valve 37 and the nine-way valve 35, then through the fourth water pump 33, and enters the battery heat exchanger 26 to absorb heat from the battery, ensuring battery temperature and safety. It then flows back to the third water pump 32 through the nine-way valve 35, repeating the cycle. At this time, the battery has an emergency thermal management requirement, so the on-board thermal management system PID4, PID5, and PID8 operate, respectively controlling the exhaust pressure (CO2) or intake superheat (R290) through the second electronic expansion valve 14, controlling the outlet water temperature of the second evaporator 15 through the second compressor speed, and controlling the battery temperature through the fourth water pump 33 speed.

[0052] Please see Figure 4 As shown, this invention provides an active cooling system for fast charging piles based on a secondary circuit, with a cooling mode for the passenger compartment during fast charging. The charging pile-side thermal management system is configured as follows: Figure 2The process shown is controlled according to the above-mentioned charging pile thermal management system workflow. In the vehicle thermal management system, ports C and G of the nine-way valve 35 are connected, ports E and F are connected, ports a and c of the first three-way valve 36 are connected, ports a and b of the second three-way valve 37 are connected, and the shut-off valve 38 is closed. At this time, the high-temperature coolant after heat exchange with the second radiator 12, driven by the second water pump 31, flows sequentially through the first three-way valve 36 and the nine-way valve 35, enters the outdoor heat exchanger 21 to release heat to the ambient air. After the heat release is completed, the coolant can be judged according to the motor temperature to see if it needs to flow through the motor to absorb heat, and then flows back to the second water pump 31, repeating the cycle. The low-temperature coolant after heat exchange with the second evaporator 15, driven by the third water pump 32, flows through the second three-way valve 37 and enters the indoor second heat exchanger 23 to absorb heat from the air inside the vehicle, reduce the air supply temperature to meet the comfort requirements of the passenger compartment, and then flows back to the third water pump 32, repeating the cycle. At this time, the battery does not have an emergency thermal management requirement, so the vehicle thermal management system PID4, PID5, PID6 and PID7 work, respectively controlling the exhaust pressure (CO2) / intake superheat (R290) through the second electronic expansion valve 14, controlling the outlet water temperature of the second evaporator 15 through the speed of the second compressor, controlling the air supply temperature of the compartment through the speed of the second water pump 31, and controlling the temperature of the compartment through the speed of the indoor fan 25.

[0053] Please see Figure 5 As shown, this invention provides an active cooling system for fast charging piles based on a secondary circuit, with a passenger compartment heating mode during fast charging. The charging pile-side thermal management system is configured as follows: Figure 2 The process shown is controlled according to the above-mentioned charging pile thermal management system workflow. In the vehicle thermal management system, ports B and C of the nine-way valve 35 are connected, and ports E and I are connected. Ports a and b of the first three-way valve 36 are connected, and ports a and c of the second three-way valve 37 are connected. The shut-off valve 38 is closed. The high-temperature coolant after exchanging heat with the second radiator 12 flows through the first three-way valve 36 under the drive of the second water pump 31, and enters the first indoor heat exchanger 22 to release heat to the air, increasing the air supply temperature to meet the comfort requirements of the passenger compartment. After releasing heat, the coolant flows back to the second water pump 31, and the cycle repeats. The low-temperature coolant after exchanging heat with the evaporator 5 flows through the second three-way valve 37 and the nine-way valve 35 under the drive of the third water pump 32, and enters the outdoor heat exchanger 21 to absorb heat from the ambient air. If the motor has residual heat, it can be recovered and then flows through the motor heat exchanger for absorption, and then flows back to the third water pump 32, and the cycle repeats. At this time, the battery does not have an emergency thermal management requirement, so the vehicle thermal management system PID4, PID5, PID6 and PID7 work, respectively controlling the exhaust pressure (CO2) or intake superheat (R290) through the second electronic expansion valve 14, controlling the outlet water temperature of the second evaporator 15 through the speed of the second compressor, controlling the air supply temperature of the compartment through the speed of the second water pump 31, and controlling the temperature of the compartment through the speed of the indoor fan 25.

[0054] Please see Figure 6 As shown, this invention provides an active cooling system for fast charging piles based on a secondary circuit, with a cooling and dehumidification mode for the passenger compartment during fast charging. The charging pile-side thermal management system is configured as follows: Figure 2 The process shown is controlled according to the above-mentioned charging pile thermal management system workflow. In the vehicle thermal management system, ports C and G of the nine-way valve 35 are connected, and ports E and F are connected. Ports a, b, and c of the first three-way valve 36 are all connected. Ports a and b of the second three-way valve 37 are connected, and the shut-off valve 38 is closed. The high-temperature coolant after exchanging heat with the second radiator 12 is driven by the second water pump 31 and flows through port a of the first three-way valve 36, then splits into two paths. One path flows out from port b and enters the indoor first heat exchanger 22 to release heat to the air. The other path flows out from port c, then flows from port G of the nine-way valve 35 into port C and then into the outdoor heat exchanger 21 to release heat to the ambient air. After the coolant has finished releasing heat, it flows from port E of the nine-way valve into port F and then the two coolant paths merge and flow back to the second water pump 31, repeating the cycle. After exchanging heat with the second evaporator 15, the low-temperature coolant, driven by the third water pump 32, flows through the second three-way valve 37 and enters the second indoor heat exchanger 23 to absorb heat from the air inside the vehicle. It then flows back to the third water pump 32, repeating the cycle. At this time, the indoor air is first cooled and dehumidified by the second indoor heat exchanger 23, and then heated to a suitable temperature by the first indoor heat exchanger 22, becoming a low-humidity, low-temperature gas, thus meeting the temperature and humidity control targets. Since the battery does not have an emergency thermal management requirement at this time, the on-board thermal management system PID4, PID5, PID6, and PID7 operate, respectively controlling the exhaust pressure (CO2) / intake superheat (R290) through the second electronic expansion valve 14, controlling the outlet water temperature of the second evaporator 15 through the second compressor speed, controlling the cabin air supply temperature through the second water pump 31 speed, and controlling the cabin temperature through the indoor fan 25 speed. In addition, the proportional distribution of the first three-way valve 36 can be adjusted by generating a map diagram through pre-tested calibration under various operating conditions on a test bench.

[0055] Please see Figure 7 As shown, this invention provides an active cooling system for fast charging piles based on a secondary circuit, with a passenger compartment heating and defogging mode during fast charging. The charging pile-side thermal management system is configured as follows: Figure 2The process shown is controlled according to the above-mentioned charging pile thermal management system workflow. In the vehicle thermal management system, ports B and C of the nine-way valve 35 are connected, and ports E and I are connected. Ports a and b of the first three-way valve 36 are connected, and ports a, b, and c of the second three-way valve 37 are connected. The shut-off valve 38 is closed. The high-temperature coolant, after exchanging heat with the second radiator 12, flows through the first three-way valve 36 under the push of the second water pump 31, and then enters the first indoor heat exchanger 22 to release heat to the indoor air. After the heat release is completed, the coolant flows back to the second water pump 31, and the cycle repeats. After exchanging heat with the second evaporator 15, the low-temperature coolant, driven by the third water pump 32, flows through port a of the second three-way valve 37 and splits into two paths. One path flows out from port b and enters the indoor second heat exchanger 23 to absorb heat from the indoor air. The other path flows out from port c, then flows from port B of the nine-way valve 35 into port C and then into the outdoor heat exchanger 21 to release heat to the ambient air. After releasing heat, the coolant flows from port E of the nine-way valve into port I and then the two coolant paths merge and flow back to the third water pump 32, repeating the cycle. At this time, the indoor air is first cooled and dehumidified by the indoor second heat exchanger 23, and then heated to a suitable temperature by the indoor first heat exchanger 22, becoming a high-temperature gas with low moisture content, which is then blown onto fogging components such as glass to remove moisture. At this time, the battery does not have an emergency thermal management requirement. Therefore, the on-board thermal management system PID4, PID5, PID6, and PID7 operate, respectively controlling the exhaust pressure (CO2) or intake superheat (R290) through the second electronic expansion valve 14, controlling the outlet water temperature of the second evaporator 15 through the speed of the second compressor, controlling the air supply temperature of the passenger compartment through the speed of the second water pump 31, and controlling the passenger compartment temperature through the speed of the indoor fan 25. In addition, the proportional distribution of the second three-way valve 37 can be adjusted by generating a map diagram through test calibration under various operating conditions on a test bench.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fast-charging pile-side active cooling system based on a secondary circuit, characterized in that, include: The charging pile thermal management system (101) is installed on the charging pile side and includes a first coolant circuit and a first refrigerant circuit. The first refrigerant circuit exchanges heat with the first coolant circuit through a first evaporator (5). The vehicle thermal management system (102) is installed on the vehicle side and includes a second coolant circuit and a second refrigerant circuit. The second refrigerant circuit exchanges heat with the second coolant circuit through a second evaporator (15). The fast charging port (205) includes piping for coolant flow; The pipeline of the first coolant circuit is operably connected to the pipeline of the second coolant circuit through the fast charging interface (205); The first coolant circuit includes a first water pump (9) connected to the fast charging interface (205), the first water pump (9) being connected to the coolant side of the first evaporator (5), and the coolant side of the first evaporator (5) being connected to the fast charging interface (205). The first refrigerant circuit includes a high-pressure pipeline of a first compressor (1), a first radiator (2), a first regenerator (3) connected in sequence, a refrigerant side of a first evaporator (5), a first gas-liquid separator (6), and a low-pressure pipeline of the first regenerator (3); The second refrigerant circuit includes a high-pressure pipeline of a second compressor (11), a second radiator (12), a second regenerator (13) connected in sequence, a refrigerant side of a second evaporator (15), a second gas-liquid separator (16), and a low-pressure pipeline of a second regenerator (13); The second coolant circuit includes a nine-way valve (35), a first three-way valve (36), a second three-way valve (37), and a shut-off valve (38) that are controllably connected to the nine-way valve (35); it also includes a motor radiator (27), an outdoor heat exchanger (21), an indoor first heat exchanger (22), an indoor second heat exchanger (23), and a battery heat exchanger (26) that are controllably connected to the nine-way valve (35).

2. The fast charging pile side active cooling system based on a secondary circuit according to claim 1, characterized in that, When the system operates in battery cooling mode during fast charging, the first three-way valve (36) guides the high-temperature coolant flowing from the outlet of the second radiator (12) to the nine-way valve (35); the nine-way valve (35) guides the high-temperature coolant from the first three-way valve (36) to the outdoor heat exchanger (21) and guides the coolant from the battery heat exchanger (26) to the second water pump (31); the second three-way valve (37) guides the low-temperature coolant flowing from the outlet of the second evaporator (15) to the nine-way valve (35); the nine-way valve (35) also guides the low-temperature coolant from the second three-way valve (37) to the battery heat exchanger (26); the shut-off valve (38) is closed.

3. The fast charging pile side active cooling system based on a secondary circuit according to claim 1, characterized in that, When the system is operating in the refrigeration mode of the passenger cabin during fast charging, the first three-way valve (36) guides the high-temperature coolant flowing out of the outlet of the second radiator (12) to the nine-way valve (35); the nine-way valve (35) guides the high-temperature coolant from the first three-way valve (36) to the outdoor heat exchanger (21); the second three-way valve (37) guides the low-temperature coolant flowing out of the outlet of the second evaporator (15) to the indoor second heat exchanger (23); and the shut-off valve (38) is closed.

4. The fast charging pile side active cooling system based on a secondary circuit according to claim 1, characterized in that, When the system is operating in the passenger cabin heating mode during fast charging, the first three-way valve (36) guides the high-temperature coolant flowing out of the outlet of the second radiator (12) to the indoor first heat exchanger (22); the second three-way valve (37) guides the low-temperature coolant flowing out of the outlet of the second evaporator (15) to the nine-way valve (35); the nine-way valve (35) guides the low-temperature coolant from the second three-way valve (37) to the outdoor heat exchanger (21); and the shut-off valve (38) is closed.

5. The fast charging pile side active cooling system based on a secondary circuit according to claim 1, characterized in that, When the system is operating in the refrigeration and dehumidification mode of the passenger cabin during fast charging, the first three-way valve (36) simultaneously guides the high-temperature coolant flowing out of the outlet of the second radiator (12) to the first indoor heat exchanger (22) and the nine-way valve (35); the nine-way valve (35) guides part of the high-temperature coolant from the first three-way valve (36) to the outdoor heat exchanger (21); the second three-way valve (37) guides the low-temperature coolant flowing out of the outlet of the second evaporator (15) to the second indoor heat exchanger (23); and the shut-off valve (38) is closed.

6. The fast charging pile side active cooling system based on a secondary circuit according to claim 1, characterized in that, When the system is operating in the cabin heating and defogging mode during fast charging, the first three-way valve (36) guides the high-temperature coolant flowing out of the outlet of the second radiator (12) to the indoor first heat exchanger (22); the second three-way valve (37) simultaneously guides the low-temperature coolant flowing out of the outlet of the second evaporator (15) to the indoor second heat exchanger (23) and the nine-way valve (35); the nine-way valve (35) guides part of the low-temperature coolant from the second three-way valve (37) to the outdoor heat exchanger (21); and the shut-off valve (38) is closed.

7. A control method for the fast charging pile side active cooling system based on a secondary circuit as described in claim 1, characterized in that, Includes the following steps: Real-time monitoring of battery temperature to determine whether the vehicle has entered fast charging mode; When entering fast charging mode, the first coolant circuit and the second coolant circuit are connected through the fast charging interface (205), and the charging pile thermal management system (101) is started. A multi-PID coupled control strategy is adopted to control the charging pile thermal management system (101) and the vehicle thermal management system (102) respectively, wherein: The control of the charging pile thermal management system (101) includes at least the following: adjusting the speed of the first compressor (1) by a first PID controller based on the difference between the outlet water temperature of the first evaporator (5) and the first target temperature; adjusting the opening degree of the first electronic expansion valve (4) by a second PID controller based on the difference between the suction superheat of the first compressor (1) and the second target superheat; and adjusting the speed of the first water pump (9) by a third PID controller based on the difference between the battery temperature and the third target temperature. The control of the vehicle thermal management system (102) includes at least the following: according to the refrigerant type of the second refrigerant circuit, selecting the difference between the discharge pressure or suction superheat of the second compressor (11) and the corresponding target value, and adjusting the opening of the second electronic expansion valve (14) through the fourth PID controller; and adjusting the speed of the second compressor (11) through the fifth PID controller based on the difference between the outlet water temperature of the second evaporator (15) and the fourth target temperature.

8. The control method for the active cooling system on the fast charging pile side based on a secondary circuit according to claim 7, characterized in that, The control of the vehicle thermal management system (102) adaptively selects control variables according to the refrigerant type of the second refrigerant circuit. When CO2 is used, the fourth PID controller adjusts based on the exhaust pressure of the second compressor (11); when R290 is used, the fourth PID controller adjusts based on the suction superheat of the second compressor (11).

9. The control method for the fast charging pile side active cooling system based on a secondary circuit according to claim 7, characterized in that, The control method also includes control of battery temperature and passenger compartment thermal management: based on the difference between battery temperature and target battery temperature, the speed of the fourth water pump (33) is adjusted by the eighth PID controller; based on the difference between passenger compartment air supply temperature or car compartment temperature and the corresponding target value, the speed of the second water pump (31) is adjusted by the sixth PID controller, and the speed of the indoor fan (25) is adjusted by the seventh PID controller.

10. The control method for the fast charging pile side active cooling system based on a secondary circuit according to claim 7, characterized in that, During the control process, the nine-way valve (35), the first three-way valve (36), the second three-way valve (37) and the shut-off valve (38) are switched to the configuration state of the corresponding control mode.

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