Method of controlling a vehicle thermal management system

Abstract

The present application provides a method of controlling a vehicle thermal management system, the method comprising the steps of: determining a vehicle required heat based on a cabin heating required heat and a battery warming required heat when a heating, ventilation, and air conditioning (HVAC) subsystem is in a heating mode; controlling operation of the HVAC subsystem and a coolant subsystem based on the determined vehicle required heat being greater than a predetermined threshold to minimize compressor work of the HVAC subsystem and to minimize heat rejection of a refrigerant circulating in the HVAC subsystem; determining a refrigerant heat absorption, wherein the refrigerant heat absorption is heat absorbed by the refrigerant from the coolant, outdoor air, and the compressor; and increasing the compressor work of the HVAC subsystem by a predetermined value based on the determined refrigerant heat absorption being greater than the refrigerant heat rejection.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit and priority of Korean Patent Application No. 10-2024-0181921, filed with the Korean Intellectual Property Office on December 9, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a method for controlling a vehicle thermal management system, and more particularly to such a method for controlling a vehicle thermal management system, which is designed to meet the vehicle’s heat requirements by optimally adjusting the compressor workload and refrigerant heat release based on the required heat. Background Technology

[0004] In recent years, with increasing public concern about energy efficiency and environmental issues, the market demand for developing environmentally friendly vehicles that can replace internal combustion engine vehicles has been growing. These environmentally friendly vehicles are mainly divided into two categories: one is electric vehicles that use fuel cells or electricity as a power source; the other is hybrid vehicles that use both an engine and a battery for power.

[0005] Such environmentally friendly vehicles may include a vehicle thermal management system for managing the heat of the passenger compartment (or passenger cabin), battery, power electronics (PE) components, etc. The vehicle thermal management system may include a heating, ventilation, and air conditioning (HVAC) subsystem for heating or cooling the air supplied to the passenger compartment. The vehicle thermal management system may also include a coolant subsystem for cooling the battery and / or PE components. The HVAC subsystem may be thermally connected to the coolant subsystem via a battery cooler and a water-cooled heat exchanger. The battery cooler may include a refrigerant passage for refrigerant flow and a coolant passage for coolant flow. The water-cooled heat exchanger may include a refrigerant passage for refrigerant flow and a coolant passage for coolant flow.

[0006] The HVAC subsystem may include a refrigerant circulation path in which the refrigerant circulates. This refrigerant circulation path may be fluidly connected to components such as a compressor, evaporator, internal condenser, heating-side expansion valve, external heat exchanger, and cooling-side expansion valve.

[0007] When the vehicle is in a relatively low outdoor air temperature (or ambient temperature) and the HVAC subsystem is operating in heating mode, the refrigerant can absorb heat from heat sources (coolant flowing through the coolant passages of the battery cooler, coolant flowing through the coolant passages of the water-cooled heat exchanger, outdoor air, and / or other heat sources). Specifically, the refrigerant can absorb heat from the outdoor air through an external heat exchanger. Optionally, the refrigerant can also absorb heat from the coolant flowing through the coolant passages of the battery cooler and / or the coolant flowing through the coolant passages of the water-cooled heat exchanger. However, when the outdoor air temperature is relatively low, the refrigerant may not be able to absorb enough heat from the heat sources. Therefore, under these relatively low-temperature environmental conditions, the coefficient of performance (COP) of the HVAC subsystem will be relatively reduced, making it difficult to meet the vehicle controller's or user-set heating requirements. In this state, energy consumption will relatively increase due to the need for an additional electric heater.

[0008] In such relatively low-temperature environments, the refrigerant can absorb heat by relatively increasing the compressor's workload. However, if the compressor's workload is unconditionally increased (e.g., revolutions per minute, hereinafter referred to as "RPM") to increase workload, the compressor's suction pressure may drop below the threshold pressure. As a result, the density of the refrigerant flowing into the compressor inlet will decrease significantly, which may actually lead to a decrease in the compressor's workload.

[0009] Furthermore, when the HVAC subsystem operates in heating mode under low-temperature conditions, and the minimum temperature of the refrigerant drops below the freezing point of the refrigeration oil contained in the refrigerant, the refrigeration oil in the refrigerant may solidify, and the refrigerant density decreases, thus limiting the compressor's RPM. Therefore, when the HVAC subsystem operates in heating mode, the amount of heat released by the refrigerant into the cabin (hereinafter referred to as "refrigerant heat release") is limited.

[0010] The information described above in this background section is intended to help understand the background of the inventive concept, and may include some technical concepts that are not yet considered prior art by those skilled in the art. Summary of the Invention

[0011] The present invention aims to solve the above-mentioned problems existing in the prior art, while maintaining the advantages achieved by the prior art.

[0012] One aspect of the present invention provides a method for controlling a vehicle thermal management system, the method being designed to meet the vehicle's required heat by optimizing the adjustment of compressor workload and refrigerant heat release based on the required heat.

[0013] According to one aspect of the present invention, a method for controlling a vehicle thermal management system may include the following steps: when the heating, ventilation, air conditioning (HVAC) subsystem is in heating mode, calculating or determining the required heat for the vehicle based on the heat required for cabin heating and the heat required for battery heating. The method further includes: based on the calculated or determined required heat for the vehicle exceeding a predetermined threshold, controlling the operation of the HVAC subsystem and the refrigerant subsystem to minimize the compressor RPM or workload of the HVAC subsystem and to minimize the heat release of the refrigerant circulating in the HVAC subsystem. The method further includes: calculating or determining the heat absorbed by the refrigerant. The heat absorbed by the refrigerant is the heat absorbed by the refrigerant from the coolant, outside air, and the compressor. The method further includes increasing the compressor workload or RPM of the HVAC subsystem by a predetermined value based on the calculated or determined heat absorbed by the refrigerant exceeding the heat release of the refrigerant.

[0014] The method further includes the following step: reducing the refrigerant heat release by a predetermined value based on the calculated or determined refrigerant heat absorption being less than or equal to the refrigerant heat release.

[0015] The method further includes the step of determining a target refrigerant mass flow rate (MF) to meet the calculated or determined heat requirements of the vehicle. The target refrigerant mass flow rate is determined based on the heat requirements of the vehicle, the current refrigerant mass flow rate, the maximum discharge pressure of the compressor, and the current discharge pressure of the compressor.

[0016] The method further includes the step of determining the compressor lower limit suction pressure that satisfies the determined target refrigerant mass flow rate. The compressor lower limit suction pressure is determined based on the target refrigerant mass flow rate, the compressor maximum operating rate, the compressor current operating rate, and the compressor current suction pressure.

[0017] The method further includes the following steps: after increasing the compressor workload or RPM, determining whether the compressor suction pressure is greater than the lower limit suction pressure. The method also includes: based on the compressor suction pressure being greater than the lower limit suction pressure, determining whether the compressor discharge pressure is greater than the upper limit discharge pressure.

[0018] The method further includes the following steps: increasing the refrigerant heat release by a predetermined value based on the compressor discharge pressure being greater than the upper limit discharge pressure and based on the vehicle's required heat being greater than or equal to the refrigerant heat release.

[0019] The method also includes the following steps: maintaining the refrigerant heat release based on the compressor discharge pressure being greater than the upper limit discharge pressure and based on the vehicle's required heat being less than the refrigerant's heat release.

[0020] The method also includes the following step: reducing the compressor workload or RPM by a predetermined value based on the compressor suction pressure being less than or equal to the lower limit suction pressure.

[0021] The method also includes the following steps: reducing the compressor workload by a predetermined value based on the compressor discharge pressure being less than or equal to the upper limit discharge pressure.

[0022] According to another aspect of the present invention, a method for controlling a vehicle thermal management system may include the following steps: when the heating, ventilation, air conditioning (HVAC) subsystem is in heating mode, calculating or determining the required heat for the vehicle based on the heat required for cabin heating and the heat required for battery heating. The method further includes the step of determining whether a second predetermined threshold is greater than the first predetermined threshold based on the vehicle's required heat being greater than a first predetermined threshold. The method further includes the step of controlling the operation of the HVAC subsystem and the refrigerant subsystem based on the second predetermined threshold being greater than the first predetermined threshold, so as to minimize the compressor workload of the HVAC subsystem and minimize the heat release of the refrigerant circulating in the HVAC subsystem. The method further includes the step of calculating or determining the refrigerant heat absorption, which is the heat absorbed by the refrigerant from the coolant, outside air, and the compressor. The method further includes the step of increasing the compressor workload or RPM of the HVAC subsystem by a predetermined value based on the calculated or determined refrigerant heat absorption being greater than the refrigerant heat release. The first predetermined threshold is the maximum heat release of the refrigerant when the HVAC subsystem is operating in a first heating mode, and the second predetermined threshold is the maximum heat release of the refrigerant when the HVAC subsystem is operating in a second heating mode. Attached Figure Description

[0023] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0024] Figure 1 A vehicle thermal management system according to one embodiment of the present invention is shown;

[0025] Figure 2 A flowchart of a method for controlling a vehicle thermal management system according to an embodiment of the present invention is shown; and

[0026] Figure 3 A flowchart of a method for controlling a vehicle thermal management system according to another embodiment of the present invention is shown. Detailed Implementation

[0027] In the following, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Throughout the drawings, the same reference numerals are used to designate the same or equivalent elements. Furthermore, in order not to unnecessarily obscure the spirit of the invention, detailed descriptions of known techniques related to the present invention have been omitted.

[0028] Terms such as first, second, A, B, (a), and (b) are used to describe elements in embodiments of the present invention. These terms are used only to distinguish one element from another. The inherent characteristics, order, sequence, etc., of the corresponding elements are not limited by these terms. Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in general dictionaries should be interpreted as having a meaning equivalent to that in the context of the relevant technical field, and should not be interpreted as having an idealized or overly formal meaning unless expressly defined in this invention. When describing a controller, module, component, device, element, etc., of the present invention as having a purpose or performing an operation, function, etc., the controller, module, component, device, element, etc., should be regarded herein as "configured" to satisfy that purpose or perform that operation or function. Each controller, module, component, device, element, etc., may be embodied individually or as part of a device, including processors and memory, such as non-transitory computer-readable media.

[0029] Reference Figure 1 According to one embodiment of the present invention, a vehicle thermal management system 10 may include: a heating, ventilation and air conditioning (HVAC) subsystem 11 thermally connected to the passenger compartment (or passenger cabin), and a coolant subsystem 12 thermally connected to the battery 51 and / or power electronics (PE) components 52.

[0030] HVAC subsystem 11 can be configured to use refrigerant to heat or cool the air in the vehicle's passenger compartment.

[0031] The refrigerant circulation path 20 can be configured to various operating modes, such as the operating mode of the HVAC subsystem 11, the cooling and heating of the battery 51, and the cooling and heating of the PE component 52, providing various circulation paths. As used herein, the terms "upstream" and "downstream" refer to the direction of refrigerant flow along the circulation path 20.

[0032] HVAC subsystem 11 may include a compressor 31, an internal condenser 32, a heating-side expansion valve 33, an external heat exchanger 34, a cooling-side expansion valve 35, and an evaporator 36, which are fluidly connected via a refrigerant circulation path 20.

[0033] The compressor 31 can be configured to compress and circulate the refrigerant. According to one embodiment, the compressor 31 can be an electric compressor driven by electrical energy.

[0034] An internal condenser 32 may be located downstream of the compressor 31, and the internal condenser 32 is configured to condense the refrigerant received from the compressor 31. In other words, the refrigerant compressed by the compressor 31 can transfer heat to the air and be condensed in the internal condenser 32. Therefore, the internal condenser 32 can use the refrigerant compressed by the compressor 31 to heat the air, and the air heated by the internal condenser 32 can be directed to the passenger cabin.

[0035] The heating-side expansion valve 33 can be located downstream of the internal condenser 32 in the refrigerant circulation path 20. Specifically, the heating-side expansion valve 33 can be located between the internal condenser 32 and the external heat exchanger 34. During heating operation of the HVAC subsystem 11, the heating-side expansion valve 33 can regulate the refrigerant flow and / or refrigerant flow rate into the external heat exchanger 34. During heating operation of the HVAC subsystem 11, the heating-side expansion valve 33 can be configured to expand the refrigerant received from the internal condenser 32. The opening degree of the heating-side expansion valve 33 can be varied under the control of the controller 100. When the opening degree of the heating-side expansion valve 33 changes, the refrigerant flow rate into the external heat exchanger 34 also changes. In other words, during heating operation of the HVAC subsystem 11, the heating-side expansion valve 33 can be controlled by the controller 100.

[0036] According to one embodiment, the heating-side expansion valve 33 may be an electronic expansion valve (EXV) with an actuator 33a. The actuator 33a may have a shaft that is movable to open or close a throttling orifice defined in the valve body of the heating-side expansion valve 33. The position of the shaft may vary depending on the rotation direction and rotation angle of the actuator 33a, thus changing the opening degree of the throttling orifice of the heating-side expansion valve 33. The controller 100 may control the operation of the actuator 33a. The heating-side expansion valve 33 may be a fully open EXV. When the HVAC subsystem 11 is not operating in heating mode, the heating-side expansion valve 33 may be fully open (the opening degree of the heating-side expansion valve 33 may be 100%), allowing refrigerant to pass through the heating-side expansion valve 33, thus preventing the refrigerant from expanding through the heating-side expansion valve 33.

[0037] An external heat exchanger 34 may be disposed together with the radiator 53 near the front grille of the vehicle and is configured to transfer heat between refrigerant flowing through its internal channels and air flowing through the outer surface of the external heat exchanger 34. An active air flap can adjust the opening of the front grille.

[0038] According to one embodiment, the cooling fan 57 may be located behind the external heat exchanger 34 and the radiator 53, which may exchange heat with the outdoor air (or ambient air) forced by the cooling fan 57, thereby further improving the heat transfer rate between the external heat exchanger 34 and the radiator 53.

[0039] During cooling operation of the HVAC subsystem 11, the external heat exchanger 34 can be configured to condense the refrigerant received from the internal condenser 32. In other words, during cooling operation of the HVAC subsystem 11, the refrigerant flowing through the external heat exchanger 34 can act as an external condenser that condenses the refrigerant by transferring heat to the ambient air. During heating operation of the HVAC subsystem 11, the external heat exchanger 34 can be configured to evaporate the refrigerant expanded by the heating-side expansion valve 33. In other words, during heating operation of the HVAC subsystem 11, the refrigerant flowing through the internal passages of the external heat exchanger 34 can act as an external evaporator that evaporates the refrigerant by absorbing heat from the ambient air. In particular, the external heat exchanger 34 can exchange heat with the ambient air forced by the cooling fan 57, thereby further improving the heat transfer rate between the refrigerant flowing through the internal passages of the external heat exchanger 34 and the ambient air.

[0040] The refrigeration-side expansion valve 35 may be located downstream of the external heat exchanger 34 on the refrigerant circulation path 20, and between the external heat exchanger 34 and the evaporator 36 on the refrigerant circulation path 20. The refrigeration-side expansion valve 35 may also be located upstream of the evaporator 36 and may regulate the refrigerant flow and / or refrigerant flow rate into the evaporator 36. During refrigeration operation of the HVAC subsystem 11, the refrigeration-side expansion valve 35 may be configured to expand the refrigerant received from the external heat exchanger 34.

[0041] According to one embodiment, the refrigeration-side expansion valve 35 may be a thermostatic expansion valve (TXV) that senses the temperature and / or pressure of the refrigerant and regulates the opening of the refrigeration-side expansion valve 35. Specifically, the refrigeration-side expansion valve 35 may be a TXV with a solenoid valve that selectively blocks or allows the flow of refrigerant into the internal passage of the refrigeration-side expansion valve 35. The solenoid valve may be opened or closed by the controller 100, thus allowing or blocking the flow of refrigerant into the refrigeration-side expansion valve 35. When the solenoid valve is open, refrigerant is allowed to flow into the refrigeration-side expansion valve 35; when the solenoid valve is closed, refrigerant is blocked from flowing into the refrigeration-side expansion valve 35. According to one embodiment, the solenoid valve may be installed in the valve body of the refrigeration-side expansion valve 35, thus opening or closing the internal passage of the refrigeration-side expansion valve 35. According to another embodiment, the solenoid valve may be located upstream of the refrigeration-side expansion valve 35, thereby selectively opening or closing the inlet of the refrigeration-side expansion valve 35. When the solenoid valve is closed, refrigerant is blocked from flowing into the refrigeration-side expansion valve 35 and the evaporator 36, thus preventing the refrigeration operation of the HVAC subsystem 11. When the solenoid valve opens, the refrigerant can be guided to the refrigeration-side expansion valve 35 and the evaporator 36. In other words, when the solenoid valve of the refrigeration-side expansion valve 35 opens to a predetermined degree, the refrigeration operation of the HVAC subsystem 11 can be performed.

[0042] HVAC subsystem 11 may include an HVAC housing 80 having a blower 86 configured to blow heated or cooled air into the passenger compartment. The HVAC housing 80 may have an inlet and an outlet and is configured to direct air into the vehicle's passenger compartment. An evaporator 36 and an internal condenser 32 may be located within the HVAC housing 80. The evaporator 36 may be configured to evaporate refrigerant and cool the air directed into the passenger compartment, and the internal condenser 32 may be configured to condense refrigerant and heat the air directed into the passenger compartment.

[0043] An air mixing door 81 can be positioned between the evaporator 36 and the internal condenser 32. When the position of the air mixing door 81 changes, the opening of the passage connecting to the internal condenser 32 within the HVAC housing 80 changes, thus adjusting the airflow into the internal condenser 32. When the position of the air mixing door 81 changes, the airflow cooled by the evaporator 36 and the airflow heated by the internal condenser 32 can be mixed in a predetermined ratio. The air cooled, heated, and mixed within the HVAC housing 80 by the evaporator 36, the internal condenser 32, and the air mixing door 81 can be guided to the front seat area of ​​the passenger cabin via the air distribution unit.

[0044] HVAC subsystem 11 may include a blower housing 85 connected to an inlet of HVAC housing 80. A blower 86 may be housed within the blower housing 85 and positioned upstream of the evaporator 36 in the airflow direction. The blower housing 85 may include an intake duct that allows indoor and / or outdoor air to flow in. Furthermore, the intake duct may include an indoor air passage for guiding indoor airflow, an outdoor air passage for guiding outdoor airflow, and a switching door positioned between the indoor and outdoor air passages. The indoor air passage may communicate with the interior of the passenger cabin, and the outdoor air passage may communicate with the exterior of the passenger cabin or the exterior of the vehicle. The switching door may be actuated by an actuator (not shown). The switching door may be configured to regulate airflow between the indoor and outdoor air passages. The switching door may be configured to move to an indoor air recirculation position, an outdoor air intake position, or an intermediate opening position. When the switching door is in the indoor air recirculation position, it blocks outdoor airflow through the outdoor air passage and allows only indoor airflow through the indoor air passage. When the switching door is in the outdoor air intake position, it blocks indoor air from flowing through the indoor air duct and allows only outdoor air to flow through the outdoor air duct. When the switching door is in the intermediate opening position, it allows both indoor and outdoor air to flow through the indoor air duct. The indoor air ratio can be determined based on the switching door's position and can be the ratio of indoor air intake flow to total air supply flow. Specifically, the indoor air ratio can be defined as the percentage of indoor air flowing into the cabin. When the switching door is in the indoor air recirculation position, the indoor air duct opening is 100%, while the outdoor air duct opening is 0%, therefore the indoor air ratio is 100%. When the switching door is in the outdoor air intake position, the outdoor air duct opening is 100%, while the indoor air duct opening is 0%, therefore the indoor air ratio is 0%. When the switching door is in the intermediate opening position, the indoor air ratio can be equal to or proportional to the opening of the indoor air duct. When the switching door is in the middle opening position, the opening of the indoor air passage can exceed 0% or be less than 100% when the switching door position is adjusted.

[0045] According to one embodiment of the HVAC subsystem 11, a liquid receiver 31a may be further included upstream of the compressor 31. The liquid receiver 31a can separate liquid refrigerant from the refrigerant, thereby preventing liquid refrigerant from flowing into the compressor 31.

[0046] The refrigerant circulation path 20 may include: a first line 21 extending from the outlet of the compressor 31 to the internal condenser 32; a second line 22 extending from the internal condenser 32 to the heating-side expansion valve 33; a third line 23 extending from the heating-side expansion valve 33 to the external heat exchanger 34; a fourth line 24 extending from the external heat exchanger 34 to the cooling-side expansion valve 35; a fifth line 25 extending from the cooling-side expansion valve 35 to the evaporator 36; and a sixth line 26 extending from the evaporator 36 to the compressor 31.

[0047] According to one embodiment of the present invention, the HVAC subsystem 11 may further include a distribution line 27 configured such that at least a portion of the refrigerant discharged from the external heat exchanger 34 flows from an upstream point of the refrigeration-side expansion valve 35 to the compressor 31. The distribution line 27 may be configured to connect the upstream point 24a of the refrigeration-side expansion valve 35 and the upstream point of the compressor 31. The inlet of the distribution line 27 may be connected at the upstream point 24a of the refrigeration-side expansion valve 35 to a fourth line 24 of the refrigerant circulation path 20. The outlet of the distribution line 27 may be connected at an upstream point of the compressor 31 to the refrigerant circulation path 20. Specifically, the outlet of the distribution line 27 may be connected at an upstream point 26a of the receiver 31a located upstream of the compressor 31 to a sixth line 26 of the refrigerant circulation path 20. Thus, at least a portion of the refrigerant can be guided to the compressor 31 via the distribution line 27. Distribution line 27 can be configured such that at least a portion of the refrigerant discharged from external heat exchanger 34 bypasses the refrigeration-side expansion valve 35 and evaporator 36 and is directed to compressor 31. Therefore, refrigerant can be distributed to distribution line 27 and fifth line 25 in a predetermined proportion.

[0048] A battery cooler 37 may be disposed on a distribution line 27 and configured to exchange heat between the refrigerant flowing through the distribution line 27 and the coolant flowing through the battery coolant line 41. The battery cooler 37 may include a refrigerant passage 37a through which the refrigerant flows and a coolant passage 37b through which the coolant flows. The refrigerant passage 37a of the battery cooler 37 may be fluidly connected to the distribution line 27. The refrigerant flowing through the refrigerant passage 37a of the battery cooler 37 may absorb heat from the coolant flowing through the coolant passage 37b of the battery cooler 37, allowing the refrigerant to be heated or evaporated within the battery cooler 37, while the coolant is cooled within the battery cooler 37. In other words, the refrigerant can absorb waste heat from the battery 51 through the battery cooler 37.

[0049] According to one embodiment of the present invention, the HVAC subsystem 11 may further include a cooler bypass line 29, which is configured such that at least a portion of the refrigerant flowing through the distribution line 27 bypasses the refrigerant passage 37a of the battery cooler 37. The cooler bypass line 29 may be configured such that refrigerant flows from an upstream point to a downstream point of the refrigerant passage 37a of the battery cooler 37. The cooler bypass line 29 may be configured to connect the upstream point of the refrigerant passage 37a of the battery cooler 37 and the upstream point 26b of the compressor 31. The inlet of the cooler bypass line 29 may be connected to the distribution line 27 at the upstream point of the refrigerant passage 37a of the battery cooler 37, and the outlet of the cooler bypass line 29 may be connected to the distribution line 27 at the upstream point 26b of the compressor 31. Therefore, a portion of the refrigerant flowing through the distribution line 27 may be guided to the compressor 31 via the cooler bypass line 29, bypassing the refrigerant passage 37a of the battery cooler 37.

[0050] According to one embodiment of the present invention, the HVAC subsystem 11 may further include a battery-side expansion valve 38 disposed upstream of the battery cooler 37 on the distribution line 27.

[0051] The battery-side expansion valve 38 can be configured to regulate the refrigerant flow and / or refrigerant flow rate into the refrigerant passage 37a of the battery cooler 37. The battery-side expansion valve 38 can be configured to expand the refrigerant received from the external heat exchanger 34. According to one embodiment, the battery-side expansion valve 38 can be an electronic expansion valve (EXV) with an actuator 38d. The controller 100 can control the operation of the actuator 38d.

[0052] The battery-side expansion valve 38 may have an inlet port 38a communicating with an external heat exchanger 34 and an outlet port 38b communicating with a refrigerant passage 37a of the battery cooler 37. The battery-side expansion valve 38 may include a valve housing and a valve member that is driven to move within the valve housing by an actuator 38d.

[0053] The valve component can be configured to open or close the inlet port 38a by the actuator 38d. When the inlet port 38a is open, the inlet port 38a can receive refrigerant discharged from the external heat exchanger 34.

[0054] The valve component can be configured to adjust the opening of the outlet port 38b by the actuator 38d. When the battery temperature exceeds a predetermined threshold temperature (i.e., when cooling is required due to relatively high battery waste heat), the opening of the outlet port 38b can be adjusted by the valve component and the actuator 38d to meet the cooling load of the battery 51, allowing the refrigerant to expand at the outlet port 38b. The refrigerant flow rate into the refrigerant passage 37a of the battery cooler 37 can be adjusted, and the expanded refrigerant is guided into the refrigerant passage 37a of the battery cooler 37. The refrigerant flowing through the refrigerant passage 37a of the battery cooler 37 can directly absorb heat from the refrigerant flowing through the refrigerant passage 37b of the battery cooler 37, allowing the refrigerant to evaporate in the refrigerant passage 37a of the battery cooler 37. When cooling of the battery 51 is required, the opening of the outlet port 38b can be adjusted, allowing the outlet port 38b to act as an expansion valve, causing the refrigerant flowing into the refrigerant passage 37a of the battery cooler 37 to expand.

[0055] According to one embodiment of the present invention, the battery-side expansion valve 38 may further include a bypass port 38c communicating with the cooler bypass line 29, and the valve component may be configured to adjust the opening degree of the bypass port 38c by the actuator 38d. When the bypass port 38c is open, the refrigerant discharged from the bypass port 38c may be guided to the compressor 31 through the cooler bypass line 29.

[0056] The bypass port 38c can be directly connected to the cooler bypass line 29. The opening of the bypass port 38c can be adjusted by the actuator 38d, thereby regulating the refrigerant flow into the cooler bypass line 29. The bypass port 38c can act as a flow control valve to regulate the refrigerant flow in the refrigerant passage 37a that bypasses the battery cooler 37.

[0057] The opening degrees of outlet port 38b and bypass port 38c can be adjusted based on the battery temperature. Therefore, the refrigerant flow rate in the refrigerant channel 37a flowing into the battery cooler 37 and the refrigerant flow rate through the cooler bypass line 29 can be adjusted according to a predetermined ratio. For example, when the battery temperature is below or equal to a predetermined threshold temperature (i.e., when the battery waste heat is relatively reduced), the opening degree of outlet port 38b can be relatively reduced, and the opening degree of bypass port 38c can be relatively increased, so that the refrigerant flow rate in the refrigerant channel 37a flowing into the battery cooler 37 is lower than the refrigerant flow rate through the cooler bypass line 29.

[0058] The water-cooled heat exchanger 46 may be located downstream of the heating-side expansion valve 33, and may be located between the heating-side expansion valve 33 and the external heat exchanger 34. The water-cooled heat exchanger 46 may include a refrigerant passage 46a through which the refrigerant flows, and a coolant passage 46b through which the coolant flows.

[0059] The refrigerant passage 46a of the water-cooled heat exchanger 46 can be fluidly connected to the third line 23 of the refrigerant circulation path 20 of the HVAC subsystem 11, so that at least a portion of the refrigerant can flow through the water-cooled heat exchanger 46 of the refrigerant circulation path 20. In other words, the refrigerant passage 46a of the water-cooled heat exchanger 46 can be fluidly connected to the third line 23 of the refrigerant circulation path 20 between the heating-side expansion valve 33 and the external heat exchanger 34.

[0060] When the HVAC subsystem 11 operates in heating mode, the refrigerant is expanded by the heating-side expansion valve 33 and then flows through the refrigerant passage 46a of the water-cooled heat exchanger 46. The refrigerant flowing through the refrigerant passage 46a of the water-cooled heat exchanger 46 absorbs heat from the coolant flowing through the coolant passage 46b of the water-cooled heat exchanger 46, allowing the refrigerant to evaporate in the water-cooled heat exchanger 46, while the coolant is cooled in the water-cooled heat exchanger 46. In other words, during the heating operation of the HVAC subsystem 11, the water-cooled heat exchanger 46 functions as an evaporator for the refrigerant.

[0061] When the HVAC subsystem 11 performs a cooling operation, the heating-side expansion valve 33 can be fully opened, preventing the refrigerant from expanding within it. The refrigerant flowing through the refrigerant passage 46a of the water-cooled heat exchanger 46 can release heat to the coolant flowing through the coolant passage 46b, allowing the refrigerant to condense within the water-cooled heat exchanger 46, while the coolant is heated within it. In other words, during the cooling operation of the HVAC subsystem 11, the water-cooled heat exchanger 46 functions as a condenser for the refrigerant.

[0062] According to one embodiment of the present invention, the HVAC subsystem 11 may further include a heated bypass line 28 configured to guide refrigerant discharged from the refrigerant passage 46a of the water-cooled heat exchanger 46 to the compressor 31. The heated bypass line 28 may be configured to connect a downstream point of the refrigerant passage 46a of the water-cooled heat exchanger 46 to an upstream point 26b of the compressor 31. Specifically, the inlet of the heated bypass line 28 may be connected at the downstream point of the refrigerant passage 46a of the water-cooled heat exchanger 46 to a third line 23 of the refrigerant circulation path 20. The outlet of the heated bypass line 28 may be connected at the upstream point 26b of the compressor 31 to a sixth line 26 of the refrigerant circulation path 20. Therefore, at least a portion of the refrigerant discharged from the refrigerant passage 46a of the water-cooled heat exchanger 46 can bypass the external heat exchanger 34 via the heated bypass line 28, thereby flowing directly from the refrigerant passage 46a of the water-cooled heat exchanger 46 to the compressor 31.

[0063] According to one embodiment of the present invention, the HVAC subsystem 11 may further include a heating control valve 39 disposed at the junction of the heating bypass line 28 and the third line 23 of the refrigerant circulation path 20. The heating control valve 39 may be configured to control the flow (refrigerant direction, flow rate, etc.) of refrigerant between the refrigerant passage 46a of the water-cooled heat exchanger 46, the external heat exchanger 34, and the compressor 31. The heating control valve 39 may be configured to control the refrigerant flow such that refrigerant discharged from the refrigerant passage 46a of the water-cooled heat exchanger 46 is selectively directed to the external heat exchanger 34 and / or the compressor 31.

[0064] The heating control valve 39 may include: an inlet port 39a communicating with a refrigerant passage 46a of a water-cooled heat exchanger 46; a first outlet port 39b communicating with an external heat exchanger 34; a second outlet port 39c communicating with a heating bypass line 28; and an actuator 39d. The heating control valve 39 may include: a valve body, and a valve member configured to be movable within the valve body by the actuator 39d.

[0065] When the heating control valve 39 performs the first switching operation to connect the inlet port 39a with the first outlet port 39b, the refrigerant discharged from the refrigerant passage 46a of the water-cooled heat exchanger 46 can be guided to the external heat exchanger 34.

[0066] When the heating control valve 39 performs the second switching operation to connect the inlet port 39a and the second outlet port 39c, the refrigerant discharged from the refrigerant passage 46a of the water-cooled heat exchanger 46 can be guided to the compressor 31 through the heating bypass line 28.

[0067] According to one embodiment of the present invention, the HVAC subsystem 11 may further include a dehumidification bypass line 72, which is configured such that refrigerant discharged from the heating-side expansion valve 33 is guided from an upstream point 23a of the refrigerant passage 46a of the water-cooled heat exchanger 46 to the evaporator 36. The dehumidification bypass line 72 may be configured to connect the upstream point 23a of the refrigerant passage 46a of the water-cooled heat exchanger 46 and the upstream point 25a of the evaporator 36. Specifically, on the second line 22, a branch line 71 may branch off from point 23a between the heating-side expansion valve 33 and the refrigerant passage 46a of the water-cooled heat exchanger 46. The inlet of the dehumidification bypass line 72 may be connected to the branch line 71, and the outlet of the dehumidification bypass line 72 may be connected to the fifth line 25 of the refrigerant circulation path 20 at the upstream point 25a of the evaporator 36.

[0068] According to one embodiment of the present invention, the HVAC subsystem 11 may further include a heat exchanger bypass line 73, which is configured such that at least a portion of the refrigerant discharged from the heating-side expansion valve 33 bypasses the refrigerant passage 46a of the water-cooled heat exchanger 46 and is directed to a downstream point 23b of the refrigerant passage 46a of the water-cooled heat exchanger 46. The heat exchanger bypass line 73 may be configured to connect an upstream point of the refrigerant passage 46a of the water-cooled heat exchanger 46 and a downstream point 23b of the refrigerant passage 46a of the water-cooled heat exchanger 46. Specifically, the inlet of the heat exchanger bypass line 73 may be connected to a branch line 71 at the upstream point of the refrigerant passage 46a of the water-cooled heat exchanger 46. The outlet of the heat exchanger bypass line 73 may be connected to a third line 23 of the refrigerant circulation path 20 at the downstream point 23b of the refrigerant passage 46a of the water-cooled heat exchanger 46. Therefore, the refrigerant discharged from the heating-side expansion valve 33 can flow from the upstream point of the refrigerant passage 46a of the water-cooled heat exchanger 46 to the downstream point of the refrigerant passage 46a of the water-cooled heat exchanger 46 through the branch line 71 and the heat exchanger bypass line 73, so that at least a portion of the refrigerant discharged from the heating-side expansion valve 33 can bypass the refrigerant passage 46a of the water-cooled heat exchanger 46.

[0069] The HVAC subsystem 11 according to one embodiment of the present invention may further include a bypass control valve 75 disposed at the connection point of the branch line 71, the dehumidification bypass line 72, and the heat exchanger bypass line 73. The bypass control valve 75 may be configured to control the flow of refrigerant (refrigerant direction, refrigerant flow rate, etc.) between the heating-side expansion valve 33, the evaporator 36, and the external heat exchanger 34. The bypass control valve 75 may be configured to control the refrigerant flow in such a way that refrigerant discharged from the heating-side expansion valve 33 is selectively guided to at least one of the refrigerant passage 46a of the evaporator 36, or a downstream point 23b of the refrigerant passage 46a of the water-cooled heat exchanger 46.

[0070] The bypass control valve 75 may include: an inlet port 75a communicating with a branch line 71; a first outlet port 75b communicating with a dehumidification bypass line 72; and a second outlet port 75c communicating with a heat exchanger bypass line 73. The bypass control valve 75 may include: a valve body and a valve member configured to move within the valve body by an actuator 75d.

[0071] When the bypass control valve 75 performs the first switching operation to close the inlet port 75a, the refrigerant discharged from the heating side expansion valve 33 can be guided to the refrigerant passage 46a of the water-cooled heat exchanger 46.

[0072] With the bypass control valve 75 performing a second switching operation to connect the inlet port 75a to the first outlet port 75b, refrigerant discharged from the heating-side expansion valve 33 can be guided to the evaporator 36 via the dehumidification bypass line 72. When cabin dehumidification is required during heating operation of the HVAC subsystem 11, the bypass control valve 75 can perform a second switching operation, such that at least a portion of the refrigerant discharged from the heating-side expansion valve 33 can be guided to the evaporator 36 via the dehumidification bypass line 72. Therefore, the refrigerant guided to the evaporator 36 can cool the air flowing over the outer surface of the evaporator 36, thereby dehumidifying the air flowing into the cabin.

[0073] When the bypass control valve 75 performs the third switching operation to connect the inlet port 75a with the second outlet port 75c, the refrigerant discharged from the heating side expansion valve 33 can bypass the refrigerant passage 46a of the water-cooled heat exchanger 46 and be guided to the downstream point 23b of the refrigerant passage 46a of the water-cooled heat exchanger 46 through the branch line 71 and the heat exchanger bypass line 73. Then, the refrigerant can flow from the downstream point 23b of the refrigerant passage 46a of the water-cooled heat exchanger 46 to the external heat exchanger 34.

[0074] According to one embodiment of the present invention, the controller 100 can control the operation of the inverter of the compressor 31, causing the motor section of the compressor 31 to operate in either an efficiency mode or a lossy mode. The inverter can be configured to cause the motor section to operate in either an efficiency mode or a lossy mode. When the motor section operates in lossy mode, the heat generated by the compressor 31 is greater than the heat generated when it operates in efficiency mode. In other words, when the motor section is driven by the inverter to operate in lossy mode, the compressor 31 generates additional heat.

[0075] The coolant subsystem 12 may include a battery coolant line 41 fluidly connected to the battery 51, a PE coolant line 42 fluidly connected to the PE component 52, and a radiator coolant line 43 fluidly connected to the radiator 53.

[0076] Furthermore, the coolant subsystem 12 may also include a coolant control valve 60, configured to fluidly connect or disconnect the battery coolant line 41, the PE coolant line 42, and the radiator coolant line 43 from each other. In other words, through various switching operations of the coolant control valve 60, the battery coolant line 41, the PE coolant line 42, and the radiator coolant line 43 can be fluidly connected or disconnected from each other, thereby controlling the flow direction of coolant among the battery coolant line 41, the PE coolant line 42, and the radiator coolant line 43.

[0077] The coolant control valve 60 may include a valve body having multiple ports 61, 62, 63, 64, 65, and 66, which are respectively connected to the battery coolant line 41, the PE coolant line 42, and the radiator coolant line 43; and a cylindrical valve member rotatable within the valve body to selectively open or close the multiple ports 61, 62, 63, 64, 65, and 66. The valve member may have multiple channels internally, which can be selectively connected to the multiple ports 61, 62, 63, 64, 65, and 66 by rotation of the valve member, such that each of the multiple ports 61, 62, 63, 64, 65, and 66 can be opened or closed, or some of the ports can be connected to each other.

[0078] Specifically, the coolant control valve 60 may include: a first battery-side port 61 connected to the inlet of the battery coolant line 41; a second battery-side port 62 connected to the outlet of the battery coolant line 41; a first PE-side port 63 connected to the inlet of the PE coolant line 42; a second PE-side port 64 connected to the outlet of the PE coolant line 42; a first radiator-side port 65 connected to the inlet of the radiator coolant line 43; and a second radiator-side port 66 connected to the outlet of the radiator coolant line 43.

[0079] Under the control of the controller 100, the coolant control valve 60 can be switched to selectively connect at least a portion of the first battery-side port 61, the second battery-side port 62, the first PE-side port 63, the second PE-side port 64, the first radiator-side port 65, or the second radiator-side port 66 to each other. Therefore, the battery coolant line 41, the PE coolant line 42, and the radiator coolant line 43 can be selectively connected or disconnected from each other, and the coolant subsystem 12 can operate in any of the multiple circulation modes that form various coolant flows.

[0080] According to one embodiment of the present invention, the coolant subsystem 12 may further include a reservoir 67 fluidly connected to the coolant control valve 60, the reservoir 67 being configured to temporarily store and replenish coolant so that the coolant circulation flow rate remains constant.

[0081] Battery coolant line 41 may be fluidly connected to battery pump 55. Coolant passage 37b of battery 51, battery heater 54 and battery cooler 37 may be fluidly connected to battery coolant line 41.

[0082] The battery 51 may have a coolant channel inside or outside, through which coolant can flow. The battery coolant line 41 may be fluidly connected to the coolant channel of the battery 51.

[0083] A battery heater 54 may be located upstream or downstream of the battery 51 and configured to heat the coolant circulating in the battery coolant line 41, thereby raising the temperature of the battery 51 by the heated coolant. According to one embodiment, the battery heater 54 may be an electric heater. According to another embodiment, the battery heater 54 may be a heater that heats the battery coolant by exchanging heat with a high-temperature fluid. (See also...) Figure 1 In the direction of coolant flow, the battery heater 54 can be located on the downstream side of the battery 51.

[0084] The battery pump 55 can be configured to force coolant circulation, and its inlet can be connected to the first battery-side port 61 of the coolant control valve 60. Therefore, coolant discharged from the first battery-side port 61 of the coolant control valve 60 can be drawn into the inlet of the battery pump 55. (Refer to...) Figure 1 The battery pump 55 can be located on the upstream side of the battery 51.

[0085] Battery cooler 37 can be located upstream or downstream of battery 51 and is configured to thermally connect HVAC subsystem 11 and battery coolant line 41. (See reference...) Figure 1 The coolant passage 37b of the battery cooler 37 can be fluidly connected to the battery coolant line 41, and the refrigerant passage 37a of the battery cooler 37 can be fluidly connected to the distribution line 27 of the HVAC subsystem 11. The coolant passage 37b can be located upstream of the battery heater 54. The coolant flowing through the coolant passage 37b can release heat to the refrigerant flowing through the refrigerant passage 37a, allowing the coolant to be cooled in the battery cooler 37, while the refrigerant can be heated or evaporated in the battery cooler 37. The outlet of the coolant passage 37b is connected to the second battery-side port 62 of the coolant control valve 60, so the coolant discharged from the coolant passage 37b can be guided to the second battery-side port 62 of the coolant control valve 60 via the battery heater 54.

[0086] The PE coolant line 42 can be fluidly connected to the PE pump 56. The PE component 52 and the water-cooled heat exchanger 46 can be fluidly connected to the PE coolant line 42.

[0087] The PE component 52 may have a coolant passage inside or outside, through which coolant can flow. The PE coolant line 42 may be fluidly connected to the coolant passage of the PE component 52.

[0088] PE component 52 may include various components such as an automatic driving controller, an integrated charging control unit (ICCU), an inverter, and a motor.

[0089] The PE pump 56 can be configured to force coolant circulation, and its inlet is connected to the first PE side port 63 of the coolant control valve 60. Therefore, coolant discharged from the first PE side port 63 of the coolant control valve 60 can be drawn into the inlet of the PE pump 56 and guided to the PE component 52. (Refer to...) Figure 1 The PE pump 56 can be installed on the upstream side of the PE component 52.

[0090] The coolant passage 46b of the water-cooled heat exchanger 46 can be located upstream or downstream of the PE component 52. The water-cooled heat exchanger 46 can be configured to thermally connect the HVAC subsystem 11 and the PE coolant line 42. (Refer to...) Figure 1 The coolant passage 46b of the water-cooled heat exchanger 46 can be fluidly connected to the PE coolant line 42. The coolant passage 46b can be located downstream of the PE component 52. The coolant flowing through the coolant passage 46b can release heat to the refrigerant flowing through the refrigerant passage 46a, thus cooling the coolant in the water-cooled heat exchanger 46, while the refrigerant can be heated or evaporated in the water-cooled heat exchanger 46. The outlet of the coolant passage 46b is connected to the second PE side port 64 of the coolant control valve 60, so the coolant discharged from the coolant passage 46b can be guided to the second PE side port 64 of the coolant control valve 60. In other words, during the heating operation of the HVAC subsystem 11, the refrigerant can absorb waste heat from the PE component 52 through the water-cooled heat exchanger 46.

[0091] Radiator coolant line 43 may be configured to connect coolant control valve 60 and radiator 53. The inlet of radiator coolant line 43 is connected to the first radiator-side port 65 of coolant control valve 60, so coolant discharged from the first radiator-side port 65 of coolant control valve 60 may be directed to the inlet of radiator 53. The outlet of radiator coolant line 43 is connected to the second radiator-side port 66 of coolant control valve 60, so coolant discharged from the outlet of radiator 53 may be directed to the second radiator-side port 66 of coolant control valve 60.

[0092] The radiator 53 may be located near the front grille of the vehicle and is configured to transfer heat between the coolant flowing through its internal channels and the air flowing through the outer surface of the radiator 53.

[0093] The controller 100 can control the operation of the coolant control valve 60 and the active damper based on the temperature of the PE component 52, the temperature of the battery 51, the outdoor air temperature (or ambient temperature), the operating conditions of the HVAC subsystem 11, etc.

[0094] According to one embodiment of the present invention, when the HVAC subsystem 11 is operating in heating mode, the controller 100 may be configured such that the heat required for cabin heating and / or battery warming (hereinafter also referred to as "vehicle required heat Q") is greater than a predetermined threshold Q. H Under the given conditions, the workload of compressor 31 and the heat release Q of refrigerant should be appropriately controlled. r To meet the heat requirements of the vehicle.

[0095] The controller 100 can calculate or determine the vehicle's required heat Q based on the heat required for cabin heating and battery heating, and appropriately control the workload of the compressor 31 and the refrigerant heat release Q based on the calculated or determined vehicle required heat Q. r .

[0096] The amount of heat required for cabin heating can be set by the user or automatically determined by the controller 100, and the amount of heat required for battery heating can be determined by the battery management system or the controller 100.

[0097] According to one embodiment, the controller 100 can adjust the workload (e.g., revolutions per minute, hereinafter referred to as "RPM") of the compressor 31. As the RPM of the compressor 31 is adjusted, its workload can be controlled.

[0098] Refrigerant heat release Q r It can be determined based on the airflow rate (AF) through the internal condenser 32 and the difference between the refrigerant temperature T1 discharged from the internal condenser 32 and the cabin temperature T2, as shown in Equation 1 below:

[0099] Q r = AF × (T1-T2) … Equation 1

[0100] Refrigerant heat release Q r It can be determined based on the air AF flowing through the internal condenser 32, the temperature T1 of the refrigerant discharged from the internal condenser 32, and the temperature T2 of the cabin.

[0101] According to one embodiment, the controller 100 can selectively control the operation of the blower 86, the air mixing door 81, the switching door of the blower housing 85, the battery pump 55, and the PE pump 56, thereby adjusting the air flow rate into the internal condenser 32, the indoor air ratio, the coolant flow rate into the battery cooler 37, and the coolant flow rate into the water-cooled heat exchanger 46, etc., thus controlling the refrigerant heat release Q. rSpecifically, controller 100 can adjust the RPM of blower 86, thereby regulating the airflow into internal condenser 32 and thus controlling refrigerant heat release. Controller 100 can adjust the position of air mixing door 81, thereby regulating the airflow into internal condenser 32 and thus controlling refrigerant heat release. When the position of the switching door of blower housing 85 changes, the indoor air ratio of HVAC housing 80 can be adjusted, thus controlling refrigerant heat release. When it is necessary to heat battery 51, controller 100 can adjust the RPM of battery pump 55, thereby regulating the coolant flow into battery cooler 37 and thus controlling refrigerant heat release. When it is necessary to heat PE component 52, controller 100 can adjust the RPM of PE pump 56, thereby regulating the coolant flow into water-cooled heat exchanger 46 and thus controlling refrigerant heat release.

[0102] Figure 2 A flowchart of a method for controlling a vehicle thermal management system according to an embodiment of the present invention is shown.

[0103] When the HVAC subsystem 11 is operating in heating mode under relatively low outdoor air temperature conditions, the controller 100 can calculate or determine the required heat Q (S1) of the vehicle based on the heat required for cabin heating and the heat required for battery heating.

[0104] Controller 100 can determine whether the heat required by the vehicle, Q, is greater than a predetermined threshold Q. H (S2). Predetermined threshold Q H This could be the maximum heat release of the refrigerant when the HVAC subsystem 11 is operating in the first heating mode, or the maximum heat release of the refrigerant when the HVAC subsystem 11 is operating in the second heating mode. In other words, the controller 100 can determine whether cabin heating needs to be performed in either the first or second heating mode. The first heating mode can refer to a heating mode that can meet the vehicle's required heat Q by absorbing heat from the refrigerant. The second heating mode can refer to a heating mode that, when it is anticipated that it will be difficult to meet the vehicle's required heat Q by absorbing heat from the refrigerant, meets the vehicle's required heat Q by increasing the temperature and pressure of the refrigerant while stopping or minimizing the heat release of the refrigerant.

[0105] If it is determined in S2 that the heat required by the vehicle, Q, is greater than a predetermined threshold Q. H (If S2 is true), then controller 100 can minimize the workload (e.g., RPM) of compressor 31 and reduce the heat release Q of refrigerant. rThe operation of the vehicle thermal management system 10 is controlled in a minimized manner (S3). The controller 100 can minimize the RPM of the compressor 31, thereby minimizing the workload of the compressor 31. The controller 100 can selectively control the operation of at least some components of the HVAC subsystem 11 and at least some components of the coolant subsystem 12, such that the refrigerant releases heat Q. r It can be adjusted to almost zero (0) or minimized. For example, controller 100 can minimize the refrigerant heat release Q by minimizing the RPM of blower 86, adjusting air mixing door 81 to close or minimize the opening of the passage connected to internal condenser 32 within HVAC housing 80, minimizing the RPM of battery pump 55, and / or minimizing the RPM of PE pump 56. r least.

[0106] If it is determined in S2 that the heat required by the vehicle, Q, is not greater than a predetermined threshold Q. H If S2 is not specified, the method according to this embodiment of the invention can be terminated.

[0107] The controller 100 can determine the target refrigerant mass flow (MF) (S4) to meet the calculated or determined heat requirement Q of the vehicle. Specifically, the target MF of the refrigerant can be determined based on the heat requirement Q of the vehicle, the current MF of the refrigerant, the maximum discharge pressure of the compressor 31, and the current discharge pressure of the compressor 31. The target MF of the refrigerant can be determined from a map or table that includes heat related to the following parameters: the maximum discharge pressure of the compressor 31, the MF of the refrigerant, and the current discharge pressure of the compressor 31.

[0108] Controller 100 can determine the lower limit suction pressure P of compressor 31. suc,limt To meet the determined target MF (S5) of the refrigerant. Specifically, the lower limit suction pressure P of compressor 31. suc,limt It can be determined based on the target MF of the refrigerant, the maximum RPM of compressor 31, the current RPM of compressor 31, and the current suction pressure of compressor 31. The lower limit suction pressure P of compressor 31... suc,limt The refrigerant mass flow rate can be determined from an MF mapping or MF table that includes the following parameters: the maximum RPM of compressor 31, the current RPM of compressor 31, and the current suction pressure of compressor 31.

[0109] Controller 100 can calculate or determine the heat absorbed by the refrigerant Q. a This refers to the heat (S6) absorbed by the refrigerant from the coolant, outdoor air, compressor 31, etc. Specifically, the heat absorbed by the refrigerant is Q. aThis can be the sum of the heat absorbed by the refrigerant from the coolant, the heat absorbed from the outside air, and the workload of the compressor 31. The refrigerant can absorb heat from the coolant through the battery cooler 37 and through the water-cooled heat exchanger 46. When the compressor 31 is running, the refrigerant can absorb heat from the compressor 31, which means that the workload of the compressor 31 can be defined as the heat absorbed by the refrigerant.

[0110] Controller 100 can determine the heat release Q of the refrigerant. r Is it less than its heat absorption Q? a Specifically, the controller 100 can determine the refrigerant heat release (Q) after correction by the correction value a. r ×a) Is it less than the heat absorbed by the refrigerant Q? a (S7). The correction value a can be a value used to adjust the rate of increase in refrigerant internal energy during heating operation of HVAC subsystem 11. For example, the correction value a can be less than 1.

[0111] If the refrigerant heat release Q is determined in S7 r Or its corrected heat release (Q) r ×a) is less than its heat absorption Q a If S7 is yes, then the controller 100 can control the operation of the compressor 31 by increasing the RPM preset value b1(RPM+b1) of the compressor 31 (S8). The preset value b1 can be a value used to stably increase the operation of the compressor 31. In other words, when the refrigerant releases heat Q... r Or its corrected heat release (Q) r ×a) is less than its heat absorption Q a Under these conditions, increasing the RPM of compressor 31 can increase its workload. When the suction pressure P of compressor 31... suc and discharge pressure P dis When the refrigerant density at the inlet of compressor 31 is increased, its workload can be increased, so the refrigerant can fully absorb heat from compressor 31 to meet the heat requirement Q of the vehicle.

[0112] If the refrigerant heat release Q is determined in S7 r Or its corrected heat release (Q) r ×a) is greater than or equal to its heat absorption Q a (If S7 is not specified), then controller 100 can reduce the heat release Q of the refrigerant. r Preset value e2(Q) r The vehicle thermal management system 10 is controlled in a manner corresponding to -e2) (S13), and then the method according to this embodiment of the invention can return to S6. When the heat required by the vehicle Q is greater than a predetermined threshold Q... H And the refrigerant releases heat Q r Or its corrected heat release (Q)r ×a) is greater than or equal to its heat absorption Q a At that time, controller 100 can reduce the heat release Q of the refrigerant. r The vehicle thermal management system 10 is controlled by a predetermined value e2. The predetermined value e2 can be used to control the heat release Q of the refrigerant. r Reduce to an appropriate level. When the vehicle's required heat Q is greater than a predetermined threshold Q. H In a state where cabin heating needs to be performed in either the first or second heating mode, the controller 100 can cause the refrigerant to release heat Q. r The operation of the vehicle thermal management system 10 is controlled in a minimal manner to minimize the heat release Q of the refrigerant before increasing the workload of the compressor 31. r Or its corrected heat release (Q) r ×a) Reduced to the refrigerant heat absorption Q a the following.

[0113] After the RPM of compressor 31 increases by a predetermined value b1, controller 100 can determine the suction pressure P of compressor 31. suc Is the lower limit of the allowable inhalation pressure P greater than the allowable lower limit? suc,limt Specifically, the controller 100 can determine the suction pressure P of the compressor 31. suc Is it greater than the corrected lower limit of inhalation pressure (P)? suc,limt +c)(S9). Modified lower limit of inhalation pressure (P) suc,limt +c) can be the lower limit of inhalation pressure P. suc,limt The sum of the first margin value c, which can be the lower limit suction pressure P used to maintain compressor 31. suc,limt The margin value.

[0114] If the suction pressure P of compressor 31 is determined in S9 suc The lower limit of inhalation pressure Psuc,limt or its correction value (P) is greater than the lower limit of inhalation pressure. suc,limt If +c)(S9 is true), then controller 100 can determine the discharge pressure P of compressor 31. dis Is the discharge pressure greater than the allowable upper limit P? dis,limt Specifically, the controller 100 can determine the discharge pressure P of the compressor 31. dis Is the discharge pressure greater than the upper limit of the correction (P)? dis,limt -d)(S10). Corrected upper limit discharge pressure (P) dis,limt -d) can be the upper limit discharge pressure P dis,limt Subtract the second margin value d, which can be the upper limit discharge pressure P used to maintain compressor 31. dis,limt The margin value.

[0115] If the suction pressure P of compressor 31 is determined in S9 suc Not greater than the lower limit of inhalation pressure P suc,limt Or its modified lower limit of inhalation pressure (P) suc,limt If +c)(S9 is not true, then the controller 100 can control the operation of the compressor 31 by reducing the predetermined RPM value b2(RPM-b2) (S15). When the suction pressure P of the compressor 31 suc Below or equal to the lower limit of inhalation pressure P suc,lim t or its correction value (P) suc,limt When +c), the RPM of compressor 31 can be reduced, thereby reducing its workload. Therefore, the suction pressure P of compressor 31 suc It can be increased to the lower limit of inhalation pressure P suc,lim t or more.

[0116] If the discharge pressure P of compressor 31 is determined in S10 dis Discharge pressure P greater than the upper limit dis,lim t or its correction value (P) dis,limt If -d)(S10 is yes), then controller 100 can determine whether the heat required by the vehicle Q is greater than or equal to the heat released by the refrigerant Q. r (S11).

[0117] If the discharge pressure P of compressor 31 is determined in S10 dis The discharge pressure P should not exceed the upper limit. dis,limt or its correction value (P) dis,limt If -d)(S10 is not true, then the controller 100 can control the operation of the compressor 31 by reducing the predetermined RPM value b2 (RPM-b2) (S15), and then the method according to this embodiment of the invention returns to S6. When the discharge pressure P of the compressor 31 dis Discharge pressure P below or equal to the upper limit dis,limt or its correction value (P) dis,limt When -d), the RPM of compressor 31 can be reduced, thereby reducing the workload of compressor 31. Therefore, the discharge pressure P of compressor 31 dis The discharge pressure can be increased to the upper limit P. dis,limt above.

[0118] If it is determined in S11 that the heat required by the vehicle Q is greater than or equal to the heat released by the refrigerant Q r (If S11 is yes), then controller 100 can increase the refrigerant heat release Q. r The vehicle thermal management system 10 is controlled to operate in a predetermined value e1 (S12). The predetermined value e1 can be used to control the heat release Q of the refrigerant. r The value is steadily increased to an appropriate level. As the operating rate (e.g., RPM) of compressor 31 increases, the suction pressure P...suc greater than the lower limit of inhalation pressure P suc,limt Discharge pressure P dis Discharge pressure P greater than the upper limit dis,limt And the refrigerant releases heat Q r Under the condition that the heat released by the refrigerant is less than the heat required by the vehicle (Q), the heat released by the refrigerant is Q. r Increase to the maximum heat release, thereby reliably meeting the vehicle's heat requirement Q.

[0119] If it is determined in S11 that the heat required by the vehicle, Q, is less than the heat released by the refrigerant, Q... r (If S11 is not specified), then the controller 100 can maintain the refrigerant heat release Q. r The vehicle thermal management system 10 is controlled in the current manner (S14), and then the method according to this embodiment of the invention returns to S6.

[0120] Figure 3 A flowchart of a method for controlling a vehicle thermal management system according to another embodiment of the present invention is shown.

[0121] The controller 100 can calculate or determine the required heat Q of the vehicle based on the heat required for cabin heating and the heat required for battery heating (S21).

[0122] Controller 100 can determine whether the heat required by the vehicle, Q, is greater than a first predetermined threshold Q. H1 (S22). In other words, controller 100 can determine whether cabin heating needs to be performed in the first heating mode. First predetermined threshold Q H1 This can be the maximum heat release of the refrigerant when the HVAC subsystem 11 is operating in the first heating mode. The first heating mode can refer to a heating mode that satisfies the vehicle's required heat Q by absorbing heat from the refrigerant.

[0123] If it is determined in S22 that the heat required by the vehicle Q is greater than a first predetermined threshold Q H1 If S22 is true, then controller 100 can determine the second predetermined threshold Q. H2 Is it greater than the first predetermined threshold Q? H1 (S23). Second predetermined threshold Q H2 This can be the maximum heat release of the refrigerant when the HVAC subsystem 11 is operating in the second heating mode. The second heating mode can refer to a heating mode that meets the vehicle's required heat Q by increasing the temperature and pressure of the refrigerant while stopping or minimizing the heat release of the refrigerant when it is anticipated that the heat required by the vehicle can not be met by the refrigerant absorbing heat.

[0124] If in S22 it is determined that the heat required by the vehicle, Q, is less than or equal to a first predetermined threshold Q H1If S22 is not specified, the method according to this embodiment of the invention may end. When the heat required by the vehicle Q is less than or equal to a first predetermined threshold Q... H1 When the refrigerant absorbs heat, the opening of the heating-side expansion valve 33 can be minimized, thereby relatively reducing the suction temperature and suction pressure of the compressor 31. Therefore, the heat absorption of the refrigerant can be relatively increased, thus meeting the vehicle's required heat Q.

[0125] If the second predetermined threshold Q is determined in S23 H2 Greater than the first predetermined threshold Q H1 If S23 is true, then controller 100 can determine that cabin heating needs to be performed in the second heating mode. In other words, when the heat required by the vehicle Q is greater than the first predetermined threshold Q... H1 And the second predetermined threshold Q H2 Greater than the first predetermined threshold Q H1 Under certain conditions, cabin heating may need to be performed in a second heating mode.

[0126] If the second predetermined threshold Q is determined in S23 H2 Greater than the first predetermined threshold Q H1 The controller 100 can minimize the workload (e.g., RPM) of the compressor 31 and reduce the heat release Q of the refrigerant. r The operation of the vehicle thermal management system 10 is controlled in a minimized manner (S24). The controller 100 can minimize the RPM of the compressor 31, thereby minimizing the workload of the compressor 31. The controller 100 can selectively control the operation of at least a portion of the components of the HVAC subsystem 11 and at least a portion of the components of the coolant subsystem 12, such that the refrigerant releases heat Q. r It can be adjusted to almost zero (0) or minimized. For example, controller 100 can minimize the RPM of blower 86, adjust air mixing door 81 to close or minimize the opening of the passage within HVAC housing 80 connected to internal condenser 32, minimize the RPM of battery pump 55 and / or minimize the RPM of PE pump 56, thereby reducing the refrigerant heat release Q. r minimize.

[0127] If the second predetermined threshold Q is determined in S23 H2 Not greater than the first predetermined threshold Q H1 If S23 is not specified, the method according to this embodiment of the invention may end. At the second predetermined threshold Q... H2 Less than or equal to the first predetermined threshold Q H1 Under these conditions, the opening degree of the heating-side expansion valve 33 can be minimized, thereby relatively reducing the suction temperature and suction pressure of the compressor 31. Therefore, the heat absorbed by the refrigerant can be relatively increased, thus meeting the vehicle's required heat Q.

[0128] The controller 100 can determine the target MF of the refrigerant used to meet the calculated or determined heat requirement Q of the vehicle (S25). Specifically, the target MF of the refrigerant can be determined based on the heat requirement Q of the vehicle, the current MF of the refrigerant, the maximum discharge pressure of the compressor 31, and the current discharge pressure of the compressor 31. The target MF of the refrigerant can be determined from a mapping or table that includes heat related to the following parameters: the maximum discharge pressure of the compressor 31, the MF of the refrigerant, and the current discharge pressure of the compressor 31.

[0129] Controller 100 can determine the lower limit suction pressure P of compressor 31. suc,limt To meet the determined target MF (S26) of the refrigerant. Specifically, the lower limit suction pressure P of compressor 31. suc,limt It can be determined based on the target MF of the refrigerant, the maximum RPM of compressor 31, the current RPM of compressor 31, and the current suction pressure of compressor 31. The lower limit suction pressure P of compressor 31... suc,limt The refrigerant mass flow rate can be determined from an MF mapping or MF table that includes the following parameters: the maximum RPM of compressor 31, the current RPM of compressor 31, and the current suction pressure of compressor 31.

[0130] Controller 100 can calculate or determine the heat absorbed by the refrigerant Q. a This refers to the heat absorbed by the refrigerant from the coolant, outdoor air, compressor 31, etc. (S27). Specifically, the heat absorbed by the refrigerant is Q. a This can be the sum of the heat absorbed by the refrigerant from the coolant, the heat absorbed from the outside air, and the workload of the compressor 31. The refrigerant can absorb heat from the coolant through the battery cooler 37 and through the water-cooled heat exchanger 46. When the compressor 31 is running, the refrigerant can absorb heat from the compressor 31, which means that the workload of the compressor 31 can be defined as the heat absorbed by the refrigerant.

[0131] Controller 100 can determine the heat release Q of the refrigerant. r Is it less than the heat absorbed by the refrigerant Q? a Specifically, the controller 100 can determine the refrigerant heat release (Q) after correction by the correction value a. r ×a) Is it less than the heat absorbed by the refrigerant Q? a (S28). The correction value a can be a value used to adjust the rate of increase in refrigerant internal energy during heating operation of HVAC subsystem 11. For example, the correction value a can be less than 1.

[0132] If the heat release Q of the refrigerant is determined in S28 r Or its corrected heat release (Q) r ×a) is less than its heat absorption Q aIf S28 is true, then the controller 100 can control the operation of the compressor 31 by increasing the RPM preset value b1(RPM+b1) of the compressor 31 (S29). The preset value b1 can be a value used to stably increase the operation of the compressor 31. In other words, when the refrigerant releases heat Q... r Or its corrected heat release (Q) r ×a) is less than the heat absorbed by the refrigerant Q a Under these conditions, when the RPM of compressor 31 is increased, the workload of compressor 31 can be increased. When the suction pressure P of compressor 31... suc and discharge pressure P dis When the refrigerant density at the inlet of compressor 31 is increased, the workload of compressor 31 can be relatively increased, so the refrigerant can fully absorb heat from compressor 31, thereby reliably meeting the heat Q required by the vehicle.

[0133] If the heat release Q of the refrigerant is determined in S28 r Or its corrected heat release (Q) r ×a) is greater than or equal to the heat absorbed by the refrigerant Q a (If S28 is not specified), then controller 100 can reduce the heat release Q of the refrigerant. r A predetermined value e2(Q) r The vehicle thermal management system 10 is controlled in a manner corresponding to -e2) (S34), and then the method according to this embodiment of the invention returns to S27. When the heat required by the vehicle Q is greater than a first predetermined threshold Q... H1 The second predetermined threshold Q H2 Greater than the first predetermined threshold Q H1 And the refrigerant releases heat Q r or its modified heat release (Q) r ×a) is greater than or equal to the heat absorbed by the refrigerant Q a At that time, the controller 100 can reduce the heat release Q of the refrigerant. r The vehicle thermal management system 10 is controlled by a predetermined value e2. The predetermined value e2 can be used to control the heat release Q of the refrigerant. r Reduce to an appropriate level. When the vehicle's required heat Q is greater than a first predetermined threshold Q. H1 And the second predetermined threshold Q H2 Greater than the first predetermined threshold Q H1 In a state where cabin heating needs to be performed in the second heating mode, the controller 100 can cause the refrigerant to release heat Q. r The vehicle thermal management system 10 is controlled in a minimal manner to release heat Q of the refrigerant before increasing the workload of the compressor 31. r Or its corrected heat release (Q) r ×a) Reduced to the refrigerant heat absorption Qa the following.

[0134] After the RPM of compressor 31 increases by a predetermined value b1, controller 100 can determine the suction pressure P of compressor 31. suc Is the lower limit of the allowable inhalation pressure P greater than the allowable lower limit? suc,limt Specifically, the controller 100 can determine the suction pressure P of the compressor 31. suc Is it greater than the corrected lower limit of inhalation pressure (P)? suc,limt +c)(S30). Modified lower limit of inhalation pressure (P) suc,limt +c) can be the lower limit of inhalation pressure P. suc,limt The sum of the first margin value c and the first margin value c can be the lower limit suction pressure P used to maintain the compressor 31. suc,limt The margin value.

[0135] If the suction pressure P of compressor 31 is determined in S30 suc greater than the lower limit of inhalation pressure P suc,limt or its correction value (P) suc,limt If (S30 is yes), then the controller 100 can determine the discharge pressure P of the compressor 31. dis Is the discharge pressure greater than the allowable upper limit P? dis,limt Specifically, the controller 100 can determine the discharge pressure P of the compressor 31. dis Is the discharge pressure greater than the upper limit of the correction (P)? dis,limt -d)(S31). Corrected upper limit discharge pressure (P) dis,limt -d) can be the upper limit discharge pressure P dis,limt Subtract the second margin value d, which can be used to maintain the upper limit discharge pressure P of compressor 31. dis,limt The margin value.

[0136] If the suction pressure P of compressor 31 is determined in S30 suc Not greater than the lower limit of inhalation pressure P suc,limt or its correction value (P) suc,limt If (S30 is not specified) +c), then the controller 100 can control the operation of the compressor 31 by reducing the predetermined RPM value b2 (RPM-b2) (S36). When the suction pressure P of the compressor 31 suc Below or equal to the lower limit of inhalation pressure P suc,limt or its correction value (P) suc,limt When +c), the RPM of compressor 31 can be reduced, thereby reducing the workload of compressor 31. Therefore, the suction pressure P of compressor 31 suc It can be increased to the lower limit of inhalation pressure P suc,limt above.

[0137] If the discharge pressure P of compressor 31 is determined in S31 dis Discharge pressure P greater than the upper limit dis,limt or its correction value (P) dis,limt If -d)(S31 is yes), then controller 100 can determine whether the heat Q required by the vehicle is greater than or equal to the heat Q released by the refrigerant. r (S32).

[0138] If the discharge pressure P of compressor 31 is determined in S31 dis The discharge pressure P should not exceed the upper limit. dis,limt or its correction value (P) dis,limt If -d)(S31 is not true), then the controller 100 can control the operation of the compressor 31 by reducing the predetermined RPM value b2 (RPM-b2) (S36), and then the method according to this embodiment of the invention returns to S27. When the discharge pressure P of the compressor 31 dis Discharge pressure P below or equal to the upper limit dis,limt or its correction value (P) dis,limt When -d), the RPM of compressor 31 can be reduced, thereby reducing its workload. Therefore, the discharge pressure P of compressor 31 dis The discharge pressure can be increased to the upper limit P. dis,limt above.

[0139] If it is determined in S32 that the heat required by the vehicle, Q, is greater than or equal to the heat released by the refrigerant, Q... r (If S32 is true), then controller 100 can increase the refrigerant heat release Q. r The vehicle thermal management system 10 is controlled to operate using a predetermined value e1 (S33). The predetermined value e1 can be used to stably release heat Q from the refrigerant. r Increase the value to an appropriate level. As the operating rate of compressor 31 (e.g., RPM) increases, the suction pressure P... suc greater than the lower limit of inhalation pressure P suc,limt Discharge pressure P dis Discharge pressure P greater than the upper limit dis,limt And the refrigerant releases heat Q r Under the condition that the heat released by the refrigerant is less than the heat required by the vehicle (Q), the heat released by the refrigerant is Q. r Increase to the maximum heat release, thereby reliably meeting the vehicle's heat requirement Q.

[0140] If it is determined in S32 that the heat required by the vehicle, Q, is less than the heat released by the refrigerant, Q... r (If S32 is not specified), then controller 100 can maintain the refrigerant heat release Q. r The operation of the vehicle thermal management system 10 is controlled in the current manner (S35), and then the method according to this embodiment of the invention returns to S27.

[0141] As described above, according to an embodiment of the present invention, when the heat required by the vehicle exceeds a predetermined threshold or when cabin heating needs to be performed in a second heating mode, the heat released by the refrigerant can be adjusted to be less than the heat absorbed by the refrigerant. In this state, when the compressor workload is increased, the compressor's suction pressure and discharge pressure can increase, thereby increasing the refrigerant density at the compressor inlet and allowing the compressor workload to increase to its maximum level, thus reliably meeting the vehicle's heat requirements.

[0142] According to an embodiment of the present invention, after increasing the workload of the compressor, under the conditions that the compressor's suction pressure is greater than the lower limit suction pressure, the discharge pressure is greater than the upper limit discharge pressure, and the refrigerant's heat release is less than the heat required by the vehicle, the refrigerant's heat release can be increased to the maximum heat release, thereby reliably meeting the vehicle's heat requirements.

[0143] Although the invention has been described above with reference to embodiments and accompanying drawings, the invention is not limited thereto. Rather, various modifications and alterations can be made to the invention by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method for controlling a vehicle thermal management system, the method comprising the following steps: When the HVAC subsystem is in heating mode, the required heat for the vehicle is determined based on the heat required for cabin heating and the heat required for battery heating. Based on the determination that the heat required by the vehicle is greater than a predetermined threshold, the operation of the HVAC subsystem and the refrigerant subsystem is controlled to minimize the workload of the compressor in the HVAC subsystem and to minimize the heat release of the refrigerant circulating in the HVAC subsystem. Determine the heat absorbed by the refrigerant, wherein the heat absorbed by the refrigerant is the heat absorbed by the refrigerant from the coolant, the outdoor air, and the compressor; as well as Based on the determined refrigerant heat absorption being greater than the refrigerant heat release, the compressor workload of the HVAC subsystem is increased by a predetermined value.

2. The method according to claim 1, further comprising the following step: Based on the determined refrigerant heat absorption being less than or equal to the refrigerant heat release, the refrigerant heat release is reduced by a predetermined value.

3. The method according to claim 1, further comprising the following step: Determine the target refrigerant mass flow rate to meet the required heat demand of the vehicle. The target mass flow rate of the refrigerant is determined based on the heat required by the vehicle, the current mass flow rate of the refrigerant, the maximum discharge pressure of the compressor, and the current discharge pressure of the compressor.

4. The method according to claim 3, further comprising the following steps: Determine the lower limit suction pressure of the compressor that satisfies the defined target refrigerant mass flow rate. The lower limit suction pressure of the compressor is determined based on the target mass flow rate of the refrigerant, the maximum workload of the compressor, the current workload of the compressor, and the current suction pressure of the compressor.

5. The method according to claim 1, further comprising the following step: After increasing the compressor's workload, determine whether the compressor's suction pressure is greater than the lower limit suction pressure; as well as Based on the fact that the compressor suction pressure is greater than the lower limit suction pressure, it is determined whether the compressor discharge pressure is greater than the upper limit discharge pressure.

6. The method according to claim 5, further comprising the following step: The refrigerant heat release is increased by a predetermined value based on the compressor discharge pressure being greater than the upper limit discharge pressure and based on the vehicle's required heat being greater than or equal to the refrigerant heat release.

7. The method according to claim 5, further comprising the following step: The refrigerant heat release is maintained based on the compressor discharge pressure being greater than the upper limit discharge pressure and based on the vehicle's required heat being less than the refrigerant's heat release.

8. The method according to claim 5, further comprising the following step: The compressor workload is reduced by a predetermined value based on the compressor suction pressure being less than or equal to the lower limit suction pressure.

9. The method according to claim 5, further comprising the following step: Based on the compressor discharge pressure being less than or equal to the upper limit discharge pressure, the compressor workload is reduced by a predetermined value.

10. A method for controlling a vehicle thermal management system, the method comprising the following steps: When the HVAC subsystem is in heating mode, the required heat for the vehicle is determined based on the heat required for cabin heating and the heat required for battery heating. Based on the fact that the heat required by the vehicle is greater than a first predetermined threshold, determine whether a second predetermined threshold is greater than the first predetermined threshold. Based on the fact that the second predetermined threshold is greater than the first predetermined threshold, the operation of the HVAC subsystem and the refrigerant subsystem is controlled to minimize the workload of the compressor in the HVAC subsystem and to minimize the heat release of the refrigerant circulating in the HVAC subsystem. Determine the heat absorbed by the refrigerant, wherein the heat absorbed by the refrigerant is the heat absorbed by the refrigerant from the coolant, outdoor air, and the compressor; and Based on the determined fact that the heat absorbed by the refrigerant is greater than the heat released by the refrigerant, the workload of the compressor in the HVAC subsystem is increased by a predetermined value. Wherein, the first predetermined threshold is the maximum heat release of the refrigerant when the HVAC subsystem is operating in the first heating mode, and The second predetermined threshold is the maximum heat release of the refrigerant when the HVAC subsystem is running in the second heating mode.

11. The method of claim 10, further comprising the step of: Based on the determined refrigerant heat absorption being less than or equal to the refrigerant heat release, the refrigerant heat release is reduced by a predetermined value.

12. The method of claim 10, further comprising the step of: Determine the target refrigerant mass flow rate to meet the required heat demand of the vehicle. The target mass flow rate of the refrigerant is determined based on the heat required by the vehicle, the current mass flow rate of the refrigerant, the maximum discharge pressure of the compressor, and the current discharge pressure of the compressor.

13. The method of claim 12, further comprising the step of: Determine the lower limit suction pressure of the compressor that satisfies the defined target refrigerant mass flow rate. The lower limit suction pressure of the compressor is determined based on the target mass flow rate of the refrigerant, the maximum workload of the compressor, the current workload of the compressor, and the current suction pressure of the compressor.

14. The method of claim 10, further comprising the step of: After increasing the compressor's workload, determine whether the compressor's suction pressure is greater than the lower limit suction pressure; and Based on the fact that the compressor suction pressure is greater than the lower limit suction pressure, it is determined whether the compressor discharge pressure is greater than the upper limit discharge pressure.

15. The method of claim 14, further comprising the step of: The refrigerant heat release is increased by a predetermined value based on the compressor discharge pressure being greater than the upper limit discharge pressure and based on the vehicle's required heat being greater than or equal to the refrigerant heat release.

16. The method of claim 14, further comprising the step of: The refrigerant heat release is maintained based on the compressor discharge pressure being greater than the upper limit discharge pressure and based on the vehicle's required heat being less than the refrigerant's heat release.

17. The method of claim 14, further comprising the step of: The compressor workload is reduced by a predetermined value based on the compressor suction pressure being less than or equal to the lower limit suction pressure.

18. The method of claim 14, further comprising the step of: Based on the compressor discharge pressure being less than or equal to the upper limit discharge pressure, the compressor workload is reduced by a predetermined value.

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