Refrigerant loop control method, control device, equipment and storage medium

Abstract

The invention discloses a refrigerant loop control method and device, equipment and a storage medium, and belongs to the technical field of vehicle control. The control method of the refrigerant loop comprises the steps that under the condition that a first refrigeration request sent by a power battery is received and a second refrigeration request sent by a passenger compartment is further received, the first temperature of a first refrigeration unit in the refrigerant loop and the second temperature of a cooling liquid loop of the power battery are obtained; according to the first temperature and the second temperature, a first target value of the refrigerant superheat degree at the outlet of the second refrigeration unit is determined; and the opening degree of a first electronic expansion valve in the refrigerant loop is controlled based on the first actual value and the first target value of the superheat degree of the refrigerant. The first target value of the superheat degree of the refrigerant at the outlet of the second refrigeration unit is determined according to the first temperature of the first refrigeration unit and the second temperature of the cooling liquid loop. According to the method, the comfort of an air conditioner in a passenger compartment and the heat dissipation safety of a power battery can be considered.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, and in particular to a refrigerant circuit control method, a control device, equipment and a storage medium. BACKGROUND

[0002] With the rapid progress of new energy vehicle technology and the improvement of consumer demand, long endurance has become one of the core trends of industry development, and large-capacity, high-energy-density power batteries have gradually become the standard configuration of new energy vehicles. Under this background, the refrigeration demand of power batteries is highlighted, for example, the heat generation of large-capacity power batteries increases sharply under high-load working conditions such as fast charging and high-speed cruising. If the temperature control is not accurate, not only will it cause the power battery charging and discharging performance to decay, but also it will cause the risk of heat runaway, which seriously threatens the safety of the vehicle.

[0003] In related technologies, battery liquid cooling technology is one of the core solutions to meet the refrigeration demand of power batteries. Through heat exchange between the refrigerant circuit of the vehicle and the cooling liquid circuit of the power battery, the refrigerant circuit can quickly take away the heat generated by the power battery, and the opening degree of the electronic expansion valve in the refrigerant circuit is adjusted to accurately control the refrigeration capacity of the refrigerant circuit, meeting the refrigeration demand of the power battery.

[0004] However, since the refrigerant circuit is also used to refrigerate the passenger compartment of the vehicle, the opening degree of the electronic expansion valve is adjusted, which easily causes temperature fluctuations in the passenger compartment. SUMMARY

[0005] The present application provides a refrigerant circuit control method, a control device, equipment and a storage medium to solve the technical problems existing in related technologies. Specifically, the following technical solutions are included.

[0006] In a first aspect, the present application provides a refrigerant circuit control method, the method comprising: in the case of receiving a first refrigeration request sent by a power battery and also receiving a second refrigeration request sent by a passenger compartment, obtaining a first temperature of a first refrigeration unit in a refrigerant circuit and a second temperature of a cooling liquid circuit of the power battery, the first refrigeration unit having a heat exchange relationship with the passenger compartment, and the cooling liquid circuit having a heat exchange relationship with a second refrigeration unit in the refrigerant circuit; determining a first target value of a refrigerant superheat degree at the outlet of the second refrigeration unit according to the first temperature and the second temperature, the refrigerant superheat degree being used to indicate the refrigeration efficiency of the second refrigeration unit; and controlling the opening degree of a first electronic expansion valve in the refrigerant circuit based on a first actual value of the refrigerant superheat degree and the first target value, the first electronic expansion valve being used to adjust the flow of refrigerant in the second refrigeration unit.

[0007] In some possible implementations, the first temperature includes a first actual temperature and a first target temperature of the first refrigeration unit, and the second temperature includes a second actual temperature and a second target temperature at the inlet of the coolant circuit. Determining the first target value of the refrigerant superheat at the outlet of the second refrigeration unit based on the first temperature and the second temperature includes: determining a first difference between the first actual temperature and the first target temperature, and a second difference between the second actual temperature and the second target temperature; querying a first reference mapping table based on the first difference and the second difference, and determining the first target value based on the query result of the first reference mapping table, wherein the first reference mapping table indicates a two-dimensional mapping relationship between the first difference, the second difference, and the first target value.

[0008] In some possible implementations, controlling the opening of the first electronic expansion valve in the refrigerant circuit based on the first actual value and the first target value of the refrigerant superheat includes: increasing the opening of the first electronic expansion valve if the first target value is less than the first actual value; and decreasing the opening of the first electronic expansion valve if the first target value is less than the first actual value.

[0009] In some possible implementations, controlling the opening of the first electronic expansion valve in the refrigerant circuit based on the first actual value and the first target value of the refrigerant superheat includes: adjusting the opening of the first electronic expansion valve based on the first actual value and the first target value within a first specified time period; after the first specified time period ends, acquiring a third actual temperature and a third target temperature at the inlet of the coolant circuit; correcting the first target value based on the third actual temperature and the third target temperature; and adjusting the opening of the first electronic expansion valve based on the corrected first target value and the first actual value.

[0010] In some possible implementations, the step of correcting the first target value based on the third actual temperature and the third target temperature includes: if the third actual temperature is lower than the third target temperature, and a first difference between the third actual temperature and the third target temperature reaches a first difference threshold, then the first target value is lowered; if the third actual temperature is higher than the third target temperature, and a second difference between the third actual temperature and the third target temperature reaches a second difference threshold, then the first target value is increased.

[0011] In some possible implementations, when the opening degree of the first electronic expansion valve is adjusted, the opening degree of the first electronic expansion valve is within a first opening degree range.

[0012] In some possible implementations, the method further includes: upon receiving the first cooling request but not receiving the second cooling request, acquiring a second actual value and a specified second target value of the refrigerant superheat; and controlling the opening degree of the first electronic expansion valve based on the second actual value and the second target value.

[0013] Secondly, this application provides a control device for a refrigerant circuit, the device comprising an acquisition module, a determination module, and an execution module; the acquisition module is configured to, upon receiving a first cooling request from a power battery and a second cooling request from a passenger compartment, acquire a first temperature of a first refrigeration unit in the refrigerant circuit and a second temperature of the coolant circuit of the power battery, wherein the first refrigeration unit has a heat exchange relationship with the passenger compartment, and the coolant circuit has a heat exchange relationship with a second refrigeration unit in the refrigerant circuit; the determination module is configured to determine a first target value of refrigerant superheat at the outlet of the second refrigeration unit based on the first temperature and the second temperature, wherein the refrigerant superheat is used to indicate the cooling efficiency of the second refrigeration unit; the execution module is configured to control the opening of a first electronic expansion valve in the refrigerant circuit based on the first actual value of the refrigerant superheat and the first target value, wherein the first electronic expansion valve is used to adjust the flow rate of refrigerant in the second refrigeration unit.

[0014] In some possible implementations, the first temperature includes a first actual temperature and a first target temperature of the first refrigeration unit, and the second temperature includes a second actual temperature and a second target temperature at the inlet of the coolant circuit. When determining a first target value of refrigerant superheat at the outlet of the second refrigeration unit based on the first temperature and the second temperature, the determining module is configured to: determine a first difference between the first actual temperature and the first target temperature, and a second difference between the second actual temperature and the second target temperature; query a first reference mapping table based on the first difference and the second difference, and determine the first target value based on the query result of the first reference mapping table, wherein the first reference mapping table indicates a two-dimensional mapping relationship between the first difference, the second difference, and the first target value.

[0015] In some possible implementations, when the execution module controls the opening of the first electronic expansion valve in the refrigerant circuit based on the first actual value and the first target value of the refrigerant superheat, it is configured to: increase the opening of the first electronic expansion valve if the first target value is less than the first actual value; and decrease the opening of the first electronic expansion valve if the first target value is less than the first actual value.

[0016] In some possible implementations, when the execution module controls the opening of the first electronic expansion valve in the refrigerant circuit based on a first actual value and a first target value of the refrigerant superheat, it is configured to: adjust the opening of the first electronic expansion valve based on the first actual value and the first target value within a first specified time period; after the first specified time period ends, acquire a third actual temperature and a third target temperature at the inlet of the coolant circuit; correct the first target value based on the third actual temperature and the third target temperature; and adjust the opening of the first electronic expansion valve based on the corrected first target value and the first actual value.

[0017] In some possible implementations, when the execution module corrects the first target value based on the third actual temperature and the third target temperature, it is configured to: lower the first target value if the third actual temperature is lower than the third target temperature and a first difference between the third actual temperature and the third target temperature reaches a first difference threshold; and raise the first target value if the third actual temperature is higher than the third target temperature and a second difference between the third actual temperature and the third target temperature reaches a second difference threshold.

[0018] In some possible implementations, when the opening degree of the first electronic expansion valve is adjusted, the opening degree of the first electronic expansion valve is within a first opening degree range.

[0019] In some possible implementations, the acquisition module is further configured to acquire a second actual value and a specified second target value of the refrigerant superheat when the first cooling request is received but the second cooling request is not received; the execution module is further configured to control the opening degree of the first electronic expansion valve based on the second actual value and the second target value.

[0020] Thirdly, this application provides an electronic device that includes the apparatus described in the second aspect of this application or any possible implementation thereof.

[0021] Fourthly, this application provides a computer program (product) including computer program / instructions, which are executed by a processor to cause a device to implement the method of the first aspect of this application or any possible implementation of the first aspect.

[0022] Fifthly, this application provides a computer-readable storage medium having stored thereon program instructions for controlling a refrigerant circuit, which, when executed by one or more processors, cause a device to implement the method of the first aspect of this application or any possible implementation thereof.

[0023] In a sixth aspect, this application provides a vehicle that includes the apparatus described in the second aspect of this application or any possible embodiment of the second aspect.

[0024] The beneficial effects of the technical solution provided in this application include at least the following: The technical solution provided in this application, when simultaneously receiving a first cooling request and a second cooling request, can obtain a first temperature of the first cooling unit and a second temperature of the coolant circuit. The first temperature of the first cooling unit, which has a heat exchange relationship with the passenger compartment, can indicate the current cooling demand of the passenger compartment, and the second temperature of the coolant circuit, which has a heat exchange relationship with the second cooling unit, can indicate the cooling demand of the power battery. This allows for corresponding control of the refrigerant circuit based on the cooling demands of the passenger compartment and the power battery. Specifically, it determines a first target value of the refrigerant superheat at the outlet of the second cooling unit based on the first and second temperatures, and controls the opening of the first electronic expansion valve based on the first target value. This facilitates the precise distribution of refrigerant flow in the refrigerant circuit under dual cooling mode, taking into account both the comfort of the passenger compartment air conditioning and the safety of the power battery heat dissipation. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of an implementation scenario provided in the embodiments of this application; Figure 2 This is a flowchart of the refrigerant circuit control method provided in the embodiments of this application; Figure 3 This is a flowchart of another refrigerant circuit control method provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of the control device for the refrigerant circuit provided in the embodiments of this application; Figure 5 This is a schematic diagram of the structure of an electronic device for controlling a refrigerant circuit provided in an embodiment of this application. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0029] Figure 1 This is a schematic diagram of an implementation scenario provided in an embodiment of this application. (Reference) Figure 1 The implementation scenario provided in this application is as a control architecture for a thermal management system in a vehicle. The control architecture for a vehicle's thermal management system includes a control unit 110, a refrigerant circuit 120, a power battery 130, and a passenger compartment 140.

[0030] The refrigerant circuit 120 and the coolant circuit in the power battery 130 have a heat exchange relationship. The coolant circuit achieves temperature regulation of the power battery 130 through heat exchange with the refrigerant circuit 120. This is used, but not limited to, under high-load conditions such as fast charging and high-speed cruising of the power battery 130, to remove the heat generated by the power battery 130 through the cooling capacity of the refrigerant circuit 120, keeping the power battery 130 within its optimal operating temperature range. The optimal operating temperature range is determined based on the cell type, chemical system, charge / discharge rate, and service life requirements of the power battery 130, and the value of the optimal operating temperature range varies depending on the actual application scenario.

[0031] The refrigerant circuit 120 also has a heat exchange relationship with the passenger compartment 140. The passenger compartment 140 achieves temperature regulation by exchanging heat with the refrigerant circuit, which is used, but not limited to, removing the heat generated in the passenger compartment 140, to provide a comfortable passenger compartment environment for the users in the passenger compartment 140.

[0032] The control unit 110 is communicatively connected to the refrigerant circuit 120, the power battery 130, and the passenger compartment 140, respectively. It acquires relevant temperature parameters and adjusts the opening of the electronic expansion valve in the refrigerant circuit 120 based on these parameters. This balances the heat dissipation safety of the power battery 130 with the air conditioning comfort of the passenger compartment 140. The relevant temperature parameters include, but are not limited to, the maximum cell temperature of the power battery 130, the inlet / outlet temperature of the coolant circuit, and the target temperature of the passenger compartment 140. The control unit 110 can be, for example, an on-board controller, a control unit, or any other type of on-board terminal capable of control functions, such as a cloud server; this application makes no limitations in this regard.

[0033] Optionally, the refrigerant circuit 120 includes, for example, a compressor, a condenser, a refrigerant distribution valve, a first refrigeration unit, a second refrigeration unit, and corresponding refrigerant piping. The compressor is used, but not limited to, to compress the low-temperature, low-pressure gaseous refrigerant, converting it into a high-temperature, high-pressure gaseous refrigerant to provide power for the refrigerant circulation; the condenser is used, but not limited to, to exchange heat between the high-temperature, high-pressure gaseous refrigerant discharged from the compressor and the outside air, condensing it into a room-temperature, high-pressure liquid refrigerant, thus storing cooling potential energy; the refrigerant distribution valve is used, but not limited to, to distribute the room-temperature, high-pressure liquid refrigerant output from the condenser to the first and second refrigeration branches as needed, realizing the switching between dual refrigeration conditions and the initial adjustment of refrigerant flow; the first refrigeration unit is located in the passenger compartment 140 and has a heat exchange relationship with the passenger compartment 140, used, but not limited to, to receive the liquid refrigerant supplied by the refrigerant distribution valve, and to reduce the temperature of the passenger compartment 140 through refrigerant evaporation and heat absorption, meeting the cooling needs of the passenger compartment 140; the second refrigeration unit is connected to the power battery 130. The coolant circuit has a heat exchange relationship and is used, but not limited to, to receive liquid refrigerant delivered by the refrigerant distribution valve. The refrigerant absorbs heat through evaporation to cool the coolant in the coolant circuit, thereby indirectly removing the heat generated by the power battery 130 during operation and achieving heat dissipation and temperature control of the power battery 130.

[0034] The refrigerant distribution valve, the second refrigeration unit, the first electronic expansion valve, and the corresponding refrigerant piping form a first refrigeration branch for providing cooling capacity to the power battery 130. The first refrigeration branch is equipped with a first electronic expansion valve, which, under the control of the control unit 110, throttles and reduces the pressure of the refrigerant flowing into the second refrigeration unit, regulating the refrigerant flow rate. The refrigerant distribution valve, the first refrigeration unit, the second electronic expansion valve, and the corresponding refrigerant piping form a second refrigeration branch for providing cooling capacity to the passenger compartment 140. The second refrigeration branch is equipped with a second electronic expansion valve, which, under the control of the control unit 110, throttles and reduces the pressure of the refrigerant flowing into the first refrigeration unit, regulating the refrigerant flow rate.

[0035] In some embodiments, the first refrigeration unit is, for example, an evaporator, and the second refrigeration unit is, for example, a refrigerant cooler, or any other device or apparatus that can be used to achieve heat exchange between the refrigerant and the target medium and to complete the refrigeration function. This application does not impose any limitations in this regard.

[0036] Those skilled in the art should understand that the above-described control unit 110, refrigerant circuit 120, power battery 130, and passenger compartment 140 are merely examples. Other existing or future control units, refrigerant circuits, power batteries, and passenger compartments that are applicable to this application should also be included within the scope of protection of this application, and are hereby incorporated by reference.

[0037] Figure 2This is a flowchart of a refrigerant circuit control method provided in an embodiment of this application. This method can, for example, be... Figure 1 The control unit shown performs the actions, and this application makes no limitations in this regard. See also Figure 2 The refrigerant circuit control method provided in this application embodiment may include steps S210-S230.

[0038] Step S210: Upon receiving a first cooling request from the power battery and a second cooling request from the passenger compartment, the first temperature of the first cooling unit in the refrigerant circuit and the second temperature of the coolant circuit of the power battery are obtained. The first cooling unit has a heat exchange relationship with the passenger compartment, and the coolant circuit has a heat exchange relationship with the second cooling unit in the refrigerant circuit.

[0039] For example, the first cooling request may be sent by the battery management system (BMS) of the power battery. For instance, when the highest cell temperature of the power battery reaches a specified first temperature threshold, the BMS automatically generates the first cooling request and sends it to the control unit of the thermal management system via the vehicle network; or, when the power battery is under high-load conditions such as fast charging or high-speed cruising, the BMS automatically generates the first cooling request and sends it to the control unit of the thermal management system via the vehicle network. The BMS is used, but is not limited to, real-time monitoring of key parameters of the power battery such as cell temperature, voltage, current, and charge / discharge rate, to diagnose and manage the operating status of the power battery, ensuring that the power battery operates within a safe and efficient range. The vehicle network may be, for example, a CAN (controller area network) bus, a LIN (local interconnect network) bus, or an Ethernet network; this application does not impose any limitations in this regard.

[0040] In some embodiments, after the power battery sends a first cooling request, if the power battery meets a first specified condition, the power battery will also send a first cancellation command to the control unit of the thermal management system, so that the thermal management system stops cooling the power battery. In this case, the control method in the refrigerant circuit provided in this application embodiment further includes: if the first cancellation command sent by the power battery is received, controlling the refrigerant circuit to stop cooling the power battery.

[0041] The second cooling request can be sent by the ACU (Air Conditioning Controller) in the passenger compartment. For example, when a user adjusts the passenger compartment temperature via the vehicle's air conditioning control panel, central touchscreen, or other interactive methods, and the adjustment direction is to lower the passenger compartment temperature, the ACU automatically generates a second cooling request and sends it to the control unit of the thermal management system via the vehicle network. Alternatively, when the vehicle's automatic air conditioning mode is on, the ACU monitors parameters such as the interior / exterior temperature of the passenger compartment and the intensity of solar radiation in real time. When it determines that the passenger compartment needs cooling to maintain a comfortable temperature range, it automatically generates a second cooling request and sends it to the control unit of the thermal management system via the vehicle network. Or, in a smart cockpit scenario, based on the user's preset cabin temperature control strategy (such as pre-cooling before entering the vehicle), the ACU actively generates a second cooling request when the trigger conditions are met and sends it to the control unit of the thermal management system via the vehicle network. The ACU is used, but is not limited to, real-time collection and processing of passenger compartment temperature control-related parameters, executing the user's air conditioning operation commands, coordinating the operating status of various components of the air conditioning system, and ensuring the comfort needs of the passenger compartment. In some embodiments, after the temperature of the passenger compartment reaches the user's expected temperature, the ACU sends a second cancellation command to the control unit of the thermal management system based on user interaction feedback or real-time monitoring feedback of the passenger compartment, so that the thermal management system stops cooling the passenger compartment. In this case, the control method in the refrigerant circuit provided in this application embodiment further includes: if the second cancellation command sent by the passenger compartment is received, controlling the refrigerant circuit to stop cooling the passenger compartment.

[0042] As mentioned above, the first refrigeration unit is, for example, an evaporator. In this case, the first temperature of the first refrigeration unit is, for example, the first actual temperature of the evaporator, the first target temperature of the evaporator, or any temperature of the evaporator. The second temperature is, for example, the second actual temperature and the second target temperature at the inlet of the coolant circuit, the temperature at the outlet of the coolant circuit, the average temperature of the coolant circuit, or any temperature of the coolant circuit. This application does not impose any limitations in this regard. The first refrigeration unit has a heat exchange relationship with the passenger compartment, that is, the refrigerant circuit cools the passenger compartment through heat exchange between the first refrigeration unit and the passenger compartment. The second refrigeration unit has a heat exchange relationship with the coolant circuit, that is, the refrigerant circuit cools the coolant circuit through heat exchange with the coolant circuit, and then indirectly cools the power battery through heat exchange between the coolant circuit and the battery cells.

[0043] Step S220: Determine a first target value for the refrigerant superheat at the outlet of the second refrigeration unit based on the first temperature and the second temperature. The refrigerant superheat is used to indicate the refrigeration efficiency of the second refrigeration unit.

[0044] For example, the refrigerant superheat at the outlet of the second refrigeration unit is the third difference between the third actual temperature of the refrigerant and the saturation temperature at the current pressure after the refrigerant in the second refrigeration unit has undergone heat exchange and evaporation with the coolant circuit. The saturation temperature indicates the critical temperature at which the refrigerant undergoes a phase change under the current pressure conditions. When the third actual temperature is higher than the saturation temperature, the refrigerant is in a gaseous state; when the third actual temperature is lower than the saturation temperature, it is in a liquid state; and when the third actual temperature equals the saturation temperature, it is in a gas-liquid equilibrium state.

[0045] Refrigerant superheat is used, but not limited to, to describe the cooling efficiency of the second refrigeration unit. For example, a larger first actual value of refrigerant superheat results in a larger third difference between the third actual temperature and the saturation temperature, indicating a higher refrigerant temperature at the outlet of the second refrigeration unit, a larger heat exchange temperature difference between the refrigerant and coolant circuits, increased irreversible losses in the heat exchange process, and a decrease in the heat absorbed per unit mass of refrigerant, thus the cooling efficiency of the second refrigeration unit shows a decreasing trend. Conversely, a smaller first actual value of refrigerant superheat results in a smaller third difference between the third actual temperature and the saturation temperature, indicating a closer refrigerant temperature at the outlet of the second refrigeration unit to the saturation temperature, a more reasonable heat exchange temperature difference between the refrigerant and coolant, and an increasing cooling efficiency of the second refrigeration unit. However, when the first actual value continuously decreases and approaches 0, the system's fault tolerance is significantly compressed, increasing the risk of superheat dropping to a negative value due to fluctuations in operating conditions.

[0046] Based on this, the minimum value of the first actual value of refrigerant overheating is a specified value greater than 0, so as to ensure that the refrigerant at the outlet of the second refrigeration unit has been completely converted into a gaseous state, avoiding liquid slugging failure, that is, after liquid refrigerant enters the compressor, it impacts the precision components of the compressor such as pistons and valve plates.

[0047] The first target value for refrigerant overheating is the expected value of refrigerant overheating at the outlet of the second refrigeration unit during system operation, while ensuring the cooling needs of the power battery and the air conditioning comfort of the passenger compartment. The refrigerant circuit provides cooling for both the power battery and the passenger compartment, resulting in a strong correlation between their cooling needs. For example, when the cooling demand of the power battery increases, it means that the first refrigeration branch in the refrigerant circuit, used for cooling the power battery, needs to allocate more refrigerant flow, thus reducing the refrigerant flow allocated to the second refrigeration branch, which is used for cooling the passenger compartment.

[0048] In view of this, the method provided in this application embodiment determines the first target value of refrigerant overheating at the outlet of the second refrigeration unit by using the first temperature of the first refrigeration unit and the second temperature of the coolant circuit. This can take into account the cooling needs of the power battery and the passenger compartment, and achieve a dynamic balance between system cooling efficiency and operational safety under dual cooling conditions.

[0049] In some embodiments, the first temperature includes a first actual temperature and a first target temperature of the first refrigeration unit, and the second temperature includes a second actual temperature and a second target temperature at the inlet of the coolant circuit. A method for determining a first target value of refrigerant superheat at the outlet of the second refrigeration unit based on the first temperature and the second temperature includes: determining a first difference between the first actual temperature and the first target temperature, and a second difference between the second actual temperature and the second target temperature; querying a first reference mapping table based on the first difference and the second difference, and determining a first target value based on the query result of the first reference mapping table, wherein the first reference mapping table indicates a two-dimensional mapping relationship between the first difference, the second difference, and the first target value.

[0050] The mapping table is, for example, a pre-calibrated two-dimensional mapping table used, but not limited to, to output a unique first target value based on the first and second differences of the input.

[0051] The first target temperature is a temperature value determined based on the user's expected temperature in the passenger compartment, used, but not limited to, to ensure the air conditioning comfort of the passenger compartment. The first actual temperature is, for example, a temperature value obtained by measuring the current temperature of the second refrigeration unit through a temperature sensor. The larger the first difference, the greater the deviation between the first actual temperature and the first target temperature. If the first difference is positive, it indicates that there is a cooling demand in the passenger compartment, and the larger the first difference, the more urgent the cooling demand in the passenger compartment, requiring more refrigerant flow. If the first difference is negative, it indicates that there is no cooling demand in the passenger compartment.

[0052] The second target temperature is a temperature value determined based on the optimal operating temperature range of the power battery. It is used, but not limited to, to ensure the safety and stability of the power battery operation and to extend its service life. The second actual temperature is, for example, the temperature value obtained by measuring the temperature of the coolant at the inlet of the coolant circuit using a temperature sensor. The larger the second difference, the greater the deviation between the second actual temperature and the second target temperature. If the second difference is positive, it indicates that there is a cooling demand in the power battery, and the larger the second difference, the more urgent the cooling demand in the power battery, requiring more refrigerant flow. If the second difference is negative, it indicates that there is no cooling demand in the power battery.

[0053] In the above method, a first difference indicating the cooling demand of the passenger compartment is determined by the first temperature of the first refrigeration unit, and a second difference indicating the cooling demand of the power battery is determined by the second temperature of the coolant circuit. This allows for precise quantification of real-time demand priorities in dual-cooling scenarios, providing data support for refrigerant circuit flow allocation and parameter control. Based on this, a first target value is determined by querying a first reference mapping table using the first and second differences. This not only balances the dual requirements of power battery heat dissipation safety and passenger compartment air conditioning comfort, allowing the first target value to be dynamically adjusted based on the first and second differences, but also reduces the real-time computational load and hardware cost investment on the vehicle's computing resources.

[0054] Step S230: The opening degree of the first electronic expansion valve in the refrigerant circuit is controlled based on the first actual value and the first target value of the refrigerant superheat. The first electronic expansion valve is used to regulate the flow rate of the refrigerant in the second refrigeration unit.

[0055] As mentioned above, the first electronic expansion valve is installed, for example, in the first refrigeration branch used to cool the power battery, to regulate the refrigerant flow rate into the second refrigeration unit, thereby changing the cooling capacity of the second refrigeration unit. For example, the greater the refrigerant flow rate into the second refrigeration unit, the stronger the cooling capacity of the second refrigeration unit; conversely, the smaller the refrigerant flow rate into the second refrigeration unit, the weaker the cooling capacity of the second refrigeration unit.

[0056] Based on this, a method for controlling the opening of the first electronic expansion valve in the refrigerant circuit based on the first actual value and the first target value of the refrigerant superheat includes, for example, increasing the opening of the first electronic expansion valve if the first target value is less than the first actual value, and decreasing the opening of the first electronic expansion valve if the first target value is less than the first actual value. For example, by using PID (Proportional-Integral-Derivative Control) dynamic control, the opening of the first electronic expansion valve can be dynamically adjusted when the first target value and the first actual value change.

[0057] In the above method, if the first target value is less than the first actual value, the temperature of the refrigerant after evaporation at the outlet of the second refrigeration unit is high, indicating that the refrigeration efficiency of the second refrigeration unit is in a state of decline, the heat exchange temperature difference between the refrigerant and the coolant is too large, and the heat absorption per unit mass of refrigerant is insufficient, which cannot efficiently meet the heat dissipation requirements of the power battery. Therefore, the opening of the first electronic expansion valve can be increased to increase the refrigerant flow into the second refrigeration unit and enhance the refrigeration capacity of the second refrigeration unit. If the first target value is greater than the first actual value, the temperature of the refrigerant after evaporation at the outlet of the second refrigeration unit is low, indicating that the superheat of the refrigerant at the outlet of the second refrigeration unit is low. There is a risk that the first actual value of the refrigerant superheat may drop below 0 due to fluctuations in operating conditions, causing compressor liquid slugging failure. Therefore, the opening of the first electronic expansion valve can be decreased to reduce the refrigerant flow into the second refrigeration unit and weaken the refrigeration capacity of the second refrigeration unit.

[0058] Considering that in practical applications, after the thermal management system's control unit simultaneously receives the first and second cooling requests, the corresponding control strategies and parameter adjustment logic will differ at different times due to variations in the urgency of the cooling demand and the system's thermal state. For example, in the initial stage of temperature regulation based on the first and second cooling requests, the temperature fluctuations in the power battery and passenger compartment are significant, as are the cooling demands. Therefore, it is necessary to continuously and dynamically adjust the first target value based on the cooling demands of the power battery and passenger compartment, and to ensure that the first actual value quickly approaches the first target value. In the later stages of temperature regulation, the temperatures of the power battery and passenger compartment enter a stable period, and the cooling demands of the power battery and passenger compartment tend to stabilize, requiring only the maintenance of a constant temperature.

[0059] In view of this, in some embodiments, controlling the opening of the first electronic expansion valve in the refrigerant circuit based on a first actual value and a first target value of refrigerant superheat includes: adjusting the opening of the first electronic expansion valve based on the first actual value and the first target value within a first specified time period; after the first specified time period ends, obtaining a third actual temperature and a third target temperature at the inlet of the coolant circuit; correcting the first target value based on the third actual temperature and the third target temperature; and adjusting the opening of the first electronic expansion valve based on the corrected first target value and the first actual value.

[0060] For example, within a first specified time period, the first target value and the first actual value are dynamic values. For instance, the first specified time period includes multiple sampling intervals. Within each sampling interval, a first actual value is acquired, and a first target value is determined by querying a first reference mapping table based on a first difference determined by a first temperature and a second difference determined by a second temperature. Based on this, there are multiple first actual values ​​and multiple first target values, and these multiple first actual values, multiple first target values, and multiple sampling intervals correspond one-to-one; that is, the first target value and the first actual value change dynamically with the change of the sampling interval. Then, within the first specified time period, the opening degree of the first electronic expansion valve is dynamically controlled based on the multiple first target values ​​and the multiple first actual values.

[0061] After the first specified duration has elapsed, the first target value and the first actual value corresponding to the latest sampling interval in the time sequence among multiple sampling intervals are taken as the first target value and the first actual value adopted after the first specified duration has elapsed. Then, the first target value corresponding to the latest sampling interval in the time sequence is corrected based on the third actual temperature and the third target temperature, and then the opening degree of the first electron expansion is adjusted based on the first target value and the first actual value corresponding to the latest sampling interval in the time sequence after the correction.

[0062] The values ​​of the first specified duration and sampling interval can be adjusted according to the actual application scenario, and this application does not impose any restrictions in this regard. The third target temperature is, for example, the expected value of the coolant temperature at the inlet of the coolant circuit after the first specified duration has ended, and the third actual temperature is, for example, the temperature value obtained by measuring the coolant temperature at the inlet of the coolant circuit through a temperature sensor after the first specified duration has ended.

[0063] For example, the first target value is corrected based on the third actual temperature and the third target temperature, including: if the third actual temperature is lower than the third target temperature, and the first difference between the third actual temperature and the third target temperature reaches a first difference threshold, then the first target value is lowered; if the third actual temperature is higher than the third target temperature, and the second difference between the third actual temperature and the third target temperature reaches a second difference threshold, then the first target value is raised. The first difference threshold and the second difference threshold are used, but not limited to, to reserve a certain hysteresis range for adjusting the first target value for refrigerant overheating, avoiding frequent adjustments to the opening of the first electronic expansion valve. The first difference threshold and the second difference threshold can be the same or different, and their values ​​can be adjusted according to the actual application scenario; this application does not impose any restrictions in this regard.

[0064] Furthermore, considering that in practical applications, a large adjustment range or high frequency of the opening of the first electronic expansion valve may affect the air conditioning comfort in the passenger compartment, in some embodiments, when adjusting the opening of the first electronic expansion valve, the adjustment frequency and range of the first electronic expansion valve are kept within a specified frequency range and opening range to ensure the stability of the air conditioning comfort in the passenger compartment.

[0065] For example, when adjusting the opening degree of the first electronic expansion valve, the opening degree of the first electronic expansion valve is within a first opening degree range. Alternatively, when adjusting the opening degree of the first electronic expansion valve, the adjustment frequency of the first electronic expansion valve is within a specified frequency range. Or, upon receiving a first revocation command, if no second revocation command is received, the first electronic expansion valve is closed after a second specified duration. The second specified duration can be adjusted according to the actual application scenario, and this application does not impose any restrictions in this regard.

[0066] For example, when adjusting the opening degree of the first electronic expansion valve, the refrigerant circuit control method provided in this application embodiment further includes: compensating for the compressor speed in the refrigerant circuit. For example, when the opening degree of the first electronic expansion valve is increased, the compressor speed compensation is N1 (N1 is greater than 0) revolutions per minute; when the opening degree of the first electronic expansion valve is decreased, the compressor speed compensation is N2 (N2 is less than 0) revolutions per minute.

[0067] The method for determining the upper and lower limits of the first opening range is, for example, as shown in the following annotation: the upper limit of the first opening range is determined based on the first difference and the highest cell temperature of the power battery; the lower limit is the minimum opening of the first electronic expansion valve. In some embodiments, the vehicle is equipped with a second reference mapping table, which is a pre-calibrated two-dimensional mapping relationship between the first difference, the highest cell temperature, and the upper limit of the first opening range, used, but not limited to, to output a unique upper limit of the first opening range based on the input first difference and the highest cell temperature.

[0068] In some embodiments, the refrigerant circuit control method provided in this application further includes: when a first cooling request is received but a second cooling request is not received, obtaining a second actual value of the refrigerant superheat and a specified second target value; controlling the opening of the first electronic expansion valve based on the second actual value and the second target value to ensure that the superheat of the refrigerant at the outlet of the second cooling unit is stable in the safe and efficient range corresponding to the second target value, so as to prioritize meeting the heat dissipation needs of the power battery.

[0069] Figure 3 This is a flowchart of another refrigerant circuit control method provided in an embodiment of this application.

[0070] likeFigure 3 As shown, when the system receives the first cooling request, it first determines whether a second cooling request has been received. If no second cooling request is received, the opening of the first electronic expansion valve is adjusted based on the first actual value and the first target value within a first specified time period. If a second cooling request is received, the opening of the first electronic expansion valve is adjusted based on the first actual value and the first target value within a first specified time period. After the first specified time period ends, the third actual temperature and the third target temperature at the coolant circuit inlet are obtained. Then, the opening of the first electronic expansion valve is adjusted based on the corrected first target value and the first actual value. After that, it determines whether a first cancellation command has been received and no second cancellation command has been received. If so, the first electronic expansion valve is closed after a second specified time period.

[0071] The technical solution provided in this application, when simultaneously receiving a first cooling request and a second cooling request, can obtain a first temperature of the first cooling unit and a second temperature of the coolant circuit. The first temperature of the first cooling unit, which has a heat exchange relationship with the passenger compartment, can indicate the current cooling demand of the passenger compartment, and the second temperature of the coolant circuit, which has a heat exchange relationship with the second cooling unit, can indicate the cooling demand of the power battery. This allows for corresponding control of the refrigerant circuit based on the cooling demands of the passenger compartment and the power battery. Specifically, it determines a first target value of the refrigerant superheat at the outlet of the second cooling unit based on the first and second temperatures, and controls the opening of the first electronic expansion valve based on the first target value. This facilitates the precise distribution of refrigerant flow in the refrigerant circuit under dual cooling mode, taking into account both the comfort of the passenger compartment air conditioning and the safety of the power battery heat dissipation.

[0072] In some other possible implementations, this application also provides a control device for a refrigerant circuit. Figure 4 This is a schematic diagram of the control device for the refrigerant circuit provided in an embodiment of this application. (Reference) Figure 4 The refrigerant circuit control device provided in this application embodiment includes an acquisition module 410, a determination module 420, and an execution module 430.

[0073] The acquisition module 410 is configured to, upon receiving a first cooling request from the power battery, and if it also receives a second cooling request from the passenger compartment, acquire the first temperature of the first cooling unit in the refrigerant circuit and the second temperature of the coolant circuit of the power battery. The first cooling unit has a heat exchange relationship with the passenger compartment, and the coolant circuit has a heat exchange relationship with the second cooling unit in the refrigerant circuit.

[0074] The determining module 420 is configured to determine a first target value of refrigerant superheat at the outlet of the second refrigeration unit based on a first temperature and a second temperature, wherein the refrigerant superheat is used to indicate the refrigeration efficiency of the second refrigeration unit.

[0075] The execution module 430 is configured to control the opening of the first electronic expansion valve in the refrigerant circuit based on a first actual value and a first target value of the refrigerant superheat. The first electronic expansion valve is used to regulate the flow rate of the refrigerant in the second refrigeration unit.

[0076] In some possible implementations, the first temperature includes a first actual temperature and a first target temperature of the first refrigeration unit, and the second temperature includes a second actual temperature and a second target temperature at the inlet of the coolant circuit. When determining the first target value of the refrigerant superheat at the outlet of the second refrigeration unit based on the first temperature and the second temperature, the determining module 420 is configured to: determine a first difference between the first actual temperature and the first target temperature, and a second difference between the second actual temperature and the second target temperature; query a first reference mapping table based on the first difference and the second difference, and determine the first target value based on the query result of the first reference mapping table, wherein the first reference mapping table indicates a two-dimensional mapping relationship between the first difference, the second difference, and the first target value.

[0077] In some possible implementations, when the execution module 430 controls the opening of the first electronic expansion valve in the refrigerant circuit based on a first actual value and a first target value of the refrigerant superheat, it is configured to: increase the opening of the first electronic expansion valve if the first target value is less than the first actual value; and decrease the opening of the first electronic expansion valve if the first target value is less than the first actual value.

[0078] In some possible implementations, when the execution module 430 controls the opening of the first electronic expansion valve in the refrigerant circuit based on a first actual value and a first target value of refrigerant superheat, it is configured to: adjust the opening of the first electronic expansion valve based on the first actual value and the first target value within a first specified time period; after the first specified time period ends, acquire a third actual temperature and a third target temperature at the inlet of the coolant circuit; correct the first target value based on the third actual temperature and the third target temperature; and adjust the opening of the first electronic expansion valve based on the corrected first target value and the first actual value.

[0079] In some possible implementations, when the execution module 430 corrects the first target value based on the third actual temperature and the third target temperature, it is configured to: lower the first target value if the third actual temperature is lower than the third target temperature and the first difference between the third actual temperature and the third target temperature reaches a first difference threshold; and raise the first target value if the third actual temperature is higher than the third target temperature and the second difference between the third actual temperature and the third target temperature reaches a second difference threshold.

[0080] In some possible implementations, when the opening degree of the first electronic expansion valve is adjusted, the opening degree of the first electronic expansion valve is within a first opening degree range.

[0081] In some possible implementations, the acquisition module 410 is further configured to acquire a second actual value of the refrigerant superheat and a specified second target value if a second cooling request is not received when a first cooling request is received; the execution module 430 is further configured to control the opening degree of the first electronic expansion valve based on the second actual value and the second target value.

[0082] It should be understood that the control device for the refrigerant circuit and the control method for the refrigerant circuit provided in the above embodiments belong to the same concept, and the specific implementation process can be found in the control method for the refrigerant circuit.

[0083] In some other possible implementations, this application also provides an electronic device for controlling a refrigerant circuit. Figure 5 This is a schematic diagram of the structure of an electronic device for controlling a refrigerant circuit provided in an embodiment of this application. See also... Figure 5 The electronic device for controlling the refrigerant circuit provided in this application embodiment includes the following structure.

[0084] Memory 510 stores at least one program instruction for controlling the refrigerant circuit. Processor 520 executes the aforementioned program instruction, causing the device to achieve the above-mentioned combination. Figure 2 The steps of the described method and its various embodiments are described below. Depending on the implementation, the processor 620 may be one or more types of processors, including but not limited to DSP (digital signal processor), ASIC (application-specific integrated circuit), FPGA (field-programmable gate array), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc., and the number of such devices may be determined according to actual needs.

[0085] In some other possible implementations, this application also provides a computer program (product) comprising computer programs / instructions, which are executed by a processor to cause the device to perform the above-described combination. Figure 2 The steps of the described method and its various embodiments.

[0086] In some other possible embodiments, this application also provides a computer-readable storage medium storing program instructions thereon for controlling a refrigerant circuit, which, when executed by one or more processors, cause the device to achieve the above-mentioned combination. Figure 2 The steps of the described method and its various embodiments are described. The computer-readable storage medium can be a readable signal medium or a readable storage medium. A readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0087] In some other possible implementations, this application also provides a vehicle, the vehicle including Figure 4 The apparatus described in several embodiments thereof.

[0088] It should also be noted that the terms "first," "second," etc. (if applicable) in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0089] The term "and / or" in the embodiments of this application is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0090] The above description is only for the purpose of enabling those skilled in the art to understand the technical solution of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this application shall be included within the scope of protection of this application.

Claims

1. A control method for a refrigerant circuit, characterized in that, The method includes: Upon receiving a first cooling request from the power battery and a second cooling request from the passenger compartment, the system obtains the first temperature of the first cooling unit in the refrigerant circuit and the second temperature of the coolant circuit of the power battery. The first cooling unit has a heat exchange relationship with the passenger compartment, and the coolant circuit has a heat exchange relationship with the second cooling unit in the refrigerant circuit. A first target value for the refrigerant superheat at the outlet of the second refrigeration unit is determined based on the first temperature and the second temperature, wherein the refrigerant superheat is used to indicate the refrigeration efficiency of the second refrigeration unit. The opening degree of the first electronic expansion valve in the refrigerant circuit is controlled based on the first actual value and the first target value of the refrigerant superheat. The first electronic expansion valve is used to regulate the flow rate of the refrigerant in the second refrigeration unit.

2. The method according to claim 1, characterized in that, The first temperature includes the first actual temperature and the first target temperature of the first refrigeration unit, and the second temperature includes the second actual temperature and the second target temperature at the inlet of the coolant circuit. Determining the first target value of the refrigerant superheat at the outlet of the second refrigeration unit based on the first temperature and the second temperature includes: Determine a first difference between the first actual temperature and the first target temperature, and a second difference between the second actual temperature and the second target temperature; The first reference mapping table is queried based on the first difference and the second difference, and the first target value is determined based on the query result of the first reference mapping table. The first reference mapping table indicates the mapping relationship between the first difference, the second difference and the first target value.

3. The method according to claim 1, characterized in that, The control of the opening degree of the first electronic expansion valve in the refrigerant circuit based on the first actual value and the first target value of the refrigerant superheat includes: If the first target value is less than the first actual value, the opening of the first electronic expansion valve will be increased. If the first target value is less than the first actual value, the opening of the first electronic expansion valve will be reduced.

4. The method according to claim 1, characterized in that, The control of the opening degree of the first electronic expansion valve in the refrigerant circuit based on the first actual value and the first target value of the refrigerant superheat includes: Within a first specified time period, the opening degree of the first electronic expansion valve is adjusted based on the first actual value and the first target value; After the first specified time period ends, the third actual temperature and the third target temperature of the inlet of the coolant circuit are obtained; The first target value is corrected based on the third actual temperature and the third target temperature; The opening degree of the first electron expansion is adjusted based on the corrected first target value and the first actual value.

5. The method according to claim 4, characterized in that, The step of correcting the first target value based on the third actual temperature and the third target temperature includes: If the third actual temperature is lower than the third target temperature, and the first difference between the third actual temperature and the third target temperature reaches a first difference threshold, then the first target value is lowered. If the third actual temperature is higher than the third target temperature, and the second difference between the third actual temperature and the third target temperature reaches the second difference threshold, then the first target value is increased.

6. The method according to any one of claims 1-5, characterized in that, When the opening degree of the first electronic expansion valve is adjusted, the opening degree of the first electronic expansion valve is within the first opening degree range.

7. The method according to any one of claims 1-5, characterized in that, The method further includes: If the first cooling request is received but the second cooling request is not received, obtain the second actual value of the refrigerant superheat and the specified second target value; The opening degree of the first electronic expansion valve is controlled based on the second actual value and the second target value.

8. A control device for a refrigerant circuit, characterized in that, The device includes an acquisition module, a determination module, and an execution module; The acquisition module is configured to, upon receiving a first cooling request from the power battery, and if it also receives a second cooling request from the passenger compartment, acquire the first temperature of the first refrigeration unit in the refrigerant circuit and the second temperature of the coolant circuit of the power battery, wherein the first refrigeration unit has a heat exchange relationship with the passenger compartment, and the coolant circuit has a heat exchange relationship with the second refrigeration unit in the refrigerant circuit. The determining module is configured to determine a first target value of refrigerant superheat at the outlet of the second refrigeration unit based on the first temperature and the second temperature, wherein the refrigerant superheat is used to indicate the refrigeration efficiency of the second refrigeration unit. The execution module is configured to control the opening of the first electronic expansion valve in the refrigerant circuit based on the first actual value and the first target value of the refrigerant superheat, wherein the first electronic expansion valve is used to adjust the flow rate of the refrigerant in the second refrigeration unit.

9. An electronic device, characterized in that, include: A memory, wherein the memory stores program instructions for controlling the refrigerant circuit; as well as, A processor, when the program instructions are executed by the processor, causes the vehicle to perform the method described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores program instructions for controlling a refrigerant circuit, which, when executed by one or more processors, cause the device to perform the method described in any one of claims 1-7.

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