Method for controlling the heating of a vehicle thermal management system

Abstract

A method for controlling heating in a vehicle thermal management system includes the following steps: when heating of the passenger compartment is required, starting the compressor of the HVAC subsystem via a controller; determining whether the heat generated from powertrain components is greater than or equal to a reference heat generated; when the heat generated is greater than or equal to the reference heat generated, starting the powertrain-side pump and stopping the battery-side pump; and exchanging heat between the refrigerant circulating in the HVAC subsystem and the powertrain coolant absorbing heat from the powertrain components.

Description

[0001] Cross-reference with related applications

[0002] This application claims priority to Korean Patent Application No. 10-2021-0046143, filed on April 8, 2021, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] This invention relates to a method for controlling the heating of a vehicle thermal management system, and more specifically, to a method for controlling the heating of a vehicle thermal management system in which, during the heating operation of the heating, ventilation, air conditioning (HVAC) subsystem, the refrigerant circulating in the HVAC subsystem selectively recovers heat from ambient air and / or waste heat from electrical / electronic components, depending on driving conditions, vehicle charging conditions, and the heating operation conditions of the HVAC subsystem. Background Technology

[0004] With increasing concern about energy efficiency and environmental issues, there is a need to develop environmentally friendly vehicles that can replace internal combustion engine vehicles. These environmentally friendly vehicles are divided into electric vehicles that use fuel cells or electricity as a power source and hybrid vehicles that use an engine and battery system.

[0005] Existing electric and hybrid vehicles employ air-cooled battery cooling systems that use internal cooled air. In recent years, research has been conducted on water-cooled battery cooling systems to extend the all-electric driving range (AER) to over 300 kilometers (200 miles). Specifically, energy density can be increased by employing structures that use water to cool the battery, such as HVAC systems and radiators. Furthermore, water-cooled battery cooling systems can make the battery system more compact by reducing the gaps between battery cells and improve battery performance and durability by maintaining a uniform temperature between the battery cells.

[0006] To realize the aforementioned water-cooled battery cooling system, a vehicle thermal management system is being researched. This system integrates a powertrain cooling subsystem for cooling the electric motor and electrical / electronic components, a battery cooling subsystem for cooling the battery, and an HVAC subsystem for heating or cooling the passenger compartment air. The HVAC subsystem includes a refrigerant circuit fluidly connected to the evaporator, compressor, condenser, and expansion valve located upstream of the evaporator, and the refrigerant can circulate through the refrigerant circuit.

[0007] The powertrain cooling subsystem includes a powertrain coolant circuit that is fluidly connected to electrical / electronic components (motors, inverters, etc.), and the coolant can circulate through this circuit. The coolant circulating through the powertrain coolant circuit can be cooled by a radiator.

[0008] The battery cooling subsystem includes a battery coolant circuit fluidly connected to the battery and a battery cooler, and coolant can circulate through the battery coolant circuit. The battery cooler can be configured to transfer heat between a branch line branching from the coolant circuit and the battery coolant circuit. In the battery cooler, coolant cooled by the coolant can cool the battery.

[0009] Since conventional electric vehicles lack an internal combustion engine, they cannot utilize its waste heat. Therefore, they are equipped with electric heaters to heat the passenger compartment. The coefficient of performance (COP) of the electric heater is 0.8-0.9, while the COP of the HVAC subsystem (heat pump system) is 2.5. Therefore, it is preferable to heat the passenger compartment through the HVAC subsystem to increase the all-electric driving range.

[0010] For example, because the power consumed by the HVAC subsystem during heating operation is reduced by approximately 24% compared to the power consumed by the electric heater, the heating operation of the HVAC subsystem can increase the pure electric driving range. When the HVAC subsystem is operating in cooling mode, the pure electric driving range of the electric vehicle is reduced by approximately 27% compared to when the HVAC subsystem is not operating. Furthermore, when the HVAC subsystem is operating in heating mode, the pure electric driving range of the electric vehicle is reduced by approximately 45% compared to when the HVAC subsystem is not operating.

[0011] The information described above in this background section is provided to aid in understanding the background of the inventive concept, and may include any technical concept known to those skilled in the art that is not considered prior art. Summary of the Invention

[0012] The present invention is intended to solve the aforementioned problems in the prior art while maintaining the advantages achieved by the prior art.

[0013] One aspect of the present invention provides a method for controlling the heating of a vehicle thermal management system, wherein during the heating operation of a heating, ventilation, and air conditioning (HVAC) subsystem, the refrigerant circulating in the HVAC subsystem selectively recovers heat from the outside air and / or waste heat from electrical / electronic components, depending on driving conditions, vehicle charging conditions, and the heating operation conditions of the HVAC subsystem, thereby achieving refrigerant evaporation performance.

[0014] According to one aspect of the present invention, a method for controlling the heating of a vehicle thermal management system including an HVAC subsystem may include the following steps: when heating of the passenger compartment is required, starting the compressor of the HVAC subsystem via a controller; determining via the controller whether the heat generated from the powertrain components is greater than or equal to a reference heat generated; and when the heat generated is greater than or equal to the reference heat generated, starting the powertrain-side pump and stopping the battery-side pump via the controller, wherein the refrigerant circulating in the HVAC subsystem may exchange heat with the powertrain coolant absorbing heat from the powertrain components.

[0015] The method may further include the following steps: when the heat generation is less than a reference heat generation, activating the powertrain-side pump and the battery-side pump via a controller, wherein the refrigerant circulating in the HVAC subsystem can exchange heat with the battery coolant absorbing heat from the ambient air, and simultaneously with the powertrain coolant absorbing heat from the powertrain components. The battery-side pump may be configured to allow battery coolant to pass through a battery radiator, which may be configured to be in contact with ambient air, and the powertrain-side pump may be configured to allow powertrain coolant to pass through the powertrain components.

[0016] The method may further include the following steps: monitoring the temperature of the powertrain coolant absorbing heat from the powertrain components and the temperature of the battery coolant absorbing heat from the ambient air via a controller; calculating the temperature difference between the powertrain coolant and the battery coolant via a controller; and determining whether the temperature difference is greater than or equal to a reference value via a controller; wherein the controller may be configured to determine that the heat generation is greater than or equal to a reference heat generation when the temperature difference is greater than or equal to the reference value, and the controller may be configured to determine that the heat generation is less than the reference heat generation when the temperature difference is less than the reference value.

[0017] The temperature of the power system coolant can be measured by a first coolant temperature sensor located downstream of the power system component along the flow direction of the power system coolant, and the temperature of the battery coolant can be measured by a second coolant temperature sensor located downstream of the battery radiator along the flow direction of the battery coolant.

[0018] According to another aspect of the present invention, a method for controlling the heating of a vehicle thermal management system including an HVAC subsystem may include the following steps: when heating of the passenger compartment is required, starting the compressor of the HVAC subsystem via a controller; determining via the controller whether the heat load required for the heating operation of the HVAC subsystem is less than or equal to a first reference load; and when the heat load is less than or equal to the first reference load, starting the battery-side pump and stopping the powertrain-side pump via the controller, wherein the refrigerant circulating in the HVAC subsystem can exchange heat with the battery coolant that absorbs heat from the ambient air; and the battery-side pump can be configured to operate at a first RPM.

[0019] The method may further include the following steps: determining by a controller whether the heat load exceeds a first reference load and is less than or equal to a second reference load; and when the heat load exceeds the first reference load and is less than or equal to the second reference load, starting the powertrain-side pump and the battery-side pump by the controller, wherein the second reference load may be higher than the first reference load, the refrigerant circulating in the HVAC subsystem may exchange heat with the powertrain coolant that absorbs heat from the powertrain components and ambient air, and may also exchange heat with the battery coolant that absorbs heat from the ambient air, the battery-side pump may be configured to operate at a second RPM greater than the first RPM, and the powertrain-side pump may be configured to operate at a fourth RPM.

[0020] The method may further include the following steps: determining, via a controller, whether the heat load exceeds a second reference load and whether the heat generated by the powertrain components is less than the heat capacity generated by the heating operation of the HVAC subsystem; and when the heat load exceeds the second reference load and the heat generated is less than the heat capacity, activating the powertrain-side pump and the battery-side pump via the controller. The refrigerant circulating in the HVAC subsystem can exchange heat with the powertrain coolant absorbing heat from the powertrain components and ambient air, and simultaneously with the battery coolant absorbing heat from the ambient air. The battery-side pump can be configured to operate at a third RPM greater than the second RPM, and the powertrain-side pump can be configured to operate at a fifth RPM greater than the fourth RPM.

[0021] The method may further include the following steps: when the heat load exceeds a second reference load and the heat generation is greater than or equal to the heat capacity, preventing the powertrain coolant from passing through the powertrain radiator and allowing the powertrain coolant to pass through the powertrain components; and starting the powertrain-side pump and stopping the battery-side pump via a controller. The refrigerant circulating in the HVAC subsystem can exchange heat with the powertrain coolant absorbing heat from the powertrain components, and the powertrain-side pump can be configured to operate at a fifth RPM.

[0022] The battery-side pump can be configured to allow battery coolant to pass through the battery radiator, the powertrain-side pump can be configured to allow powertrain coolant to pass through powertrain components and the powertrain radiator, the battery radiator can be configured to be in contact with ambient air, and the powertrain radiator can be configured to be in contact with ambient air. 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 of the embodiments in conjunction with the accompanying drawings:

[0024] Figure 1 A vehicle thermal management system according to an exemplary embodiment of the present invention is shown.

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

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

[0027] Figure 4 A flowchart illustrating a method for controlling the heating of a vehicle thermal management system according to another exemplary embodiment of the present invention is shown.

[0028] Explanation of reference numerals in the attached figures

[0029] 11: HVAC Subsystem

[0030] 12: Battery Cooling Subsystem

[0031] 13: Powertrain Cooling Subsystem

[0032] 15: Cooling-side expansion valve

[0033] 16: Heating side expansion valve

[0034] 17: Cooler-side expansion valve

[0035] 21: Refrigerant Circuit

[0036] 22: Battery coolant circuit

[0037] 23: Powertrain Coolant Circuit

[0038] 30: HVAC box

[0039] 31: Evaporator

[0040] 32: Compressor

[0041] 33: Internal condenser

[0042] 35: External heat exchanger

[0043] 36: Branch pipes

[0044] 37: Battery Cooler

[0045] 38: Liquid reservoir

[0046] 39: Refrigerant bypass pipeline

[0047] 41: Battery Pack

[0048] 42: Heater

[0049] 43: Battery Heatsink

[0050] 44: First battery side pump

[0051] 45: Second battery side pump

[0052] 46: First battery bypass pipe

[0053] 47: Second battery bypass pipe

[0054] 48: Storage tank

[0055] 51: Electric motor

[0056] 52: Electrical / Electronic Components

[0057] 53: Powertrain Radiator

[0058] 54: Power system side pump

[0059] 55: Power system bypass pipe

[0060] 56: Storage tank

[0061] 61: First three-way valve

[0062] 62: Second three-way valve

[0063] 63: Third three-way valve

[0064] 70: Water-cooled heat exchanger

[0065] 81: Internal temperature sensor

[0066] 82: Ambient temperature sensor

[0067] 83: Solar Radiation Sensor

[0068] 84: First coolant temperature sensor

[0069] 85: Second coolant temperature sensor Detailed Implementation

[0070] In the following, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals will always be used to denote the same or equivalent elements. Furthermore, to avoid unnecessarily obscuring the spirit of the invention, detailed descriptions of well-known techniques associated with the invention will be excluded.

[0071] Although the exemplary embodiments are described as using multiple units to perform the exemplary processes, it should be understood that the exemplary processes may also be performed by one or more modules. Furthermore, it should be understood that the term controller / control unit refers to a hardware device that includes a memory and a processor and is specifically programmed to perform the processes described herein. The memory is configured to store modules and the processor is specifically configured to execute said modules to perform one or more processes further described below.

[0072] Furthermore, the control logic of this invention can be embodied on a non-transitory computer-readable medium containing executable program instructions that are executed by a processor, controller / control unit, etc. Examples of computer-readable media include, but are not limited to, ROM, RAM, optical disc (CD)-ROM, magnetic tape, floppy disk, flash drive, smart card, and optical data storage device. The computer-readable medium can also be distributed across a network-connected computer system, enabling the computer-readable medium to be stored and executed in a distributed manner, for example, via a telematics server or a controller area network (CAN).

[0073] Terms such as first, second, A, B, (a), and (b) are used to describe elements in exemplary embodiments of the invention. These terms are used only to distinguish one element from another, and the inherent characteristics, order, or sequence of the corresponding elements are not limited by these terms. Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms defined in commonly used dictionaries should be interpreted as having the same meaning as in the context of the relevant field and should not be interpreted as having an ideal or overly formal meaning unless expressly defined in this application.

[0074] In this specification, the term "heat load" is defined as the amount of heat required to maintain the desired heating temperature set by the user or automatically set by the controller based on the vehicle's internal / external conditions.

[0075] In this specification, the term "heat capacity" is defined as the amount of heat supplied to the passenger compartment by the internal condenser of the HVAC subsystem when the HVAC subsystem is operating in heating mode.

[0076] Reference Figure 1According to an exemplary embodiment of the present invention, a vehicle thermal management system may include: an HVAC subsystem 11 having a refrigerant circuit 21 through which refrigerant circulates; a battery cooling subsystem 12 having a battery coolant circuit 22 through which battery coolant for cooling battery pack 41 circulates; and a powertrain cooling subsystem 13 having a powertrain coolant circuit 23 through which powertrain coolant for cooling powertrain components (motor 51 and electrical / electronic components 52) circulates.

[0077] HVAC subsystem 11 can be configured to use refrigerant circulating in refrigerant circuit 21 to heat or cool air in the vehicle passenger compartment. Refrigerant circuit 21 can be fluidly connected to evaporator 31, compressor 32, internal condenser 33, heating-side expansion valve 16, water-cooled heat exchanger 70, external heat exchanger 35, and cooling-side expansion valve 15. Figure 1 In this circuit, the refrigerant can pass through the refrigerant circuit 21 in the following order: compressor 32, internal condenser 33, heating-side expansion valve 16, water-cooled heat exchanger 70, external heat exchanger 35, cooling-side expansion valve 15, and evaporator 31.

[0078] Evaporator 31 can be configured to evaporate refrigerant received from cooling-side expansion valve 15. In other words, the refrigerant expanded by cooling-side expansion valve 15 can evaporate by absorbing heat from the air in evaporator 31. During cooling operation of HVAC subsystem 11, evaporator 31 can be configured to cool air using refrigerant cooled by external heat exchanger 35 and expanded by cooling-side expansion valve 15, and the air cooled by evaporator 31 can be introduced into the passenger compartment.

[0079] Compressor 32 may be configured to compress refrigerant received from evaporator 31 and / or battery cooler 37. According to an exemplary embodiment, compressor 32 may be an electrically driven compressor. Internal condenser 33 may be configured to condense the refrigerant received from compressor 32, thus air passing through internal condenser 33 may be heated by internal condenser 33. When air heated by internal condenser 33 is introduced into the passenger compartment, the passenger compartment may be heated. The refrigerant condensed in internal condenser 33 may have a relatively low temperature, thus cryogenic refrigerant may flow into water-cooled heat exchanger 70.

[0080] An external heat exchanger 35 may be arranged adjacent to the vehicle's front grille. Since the external heat exchanger 35 is exposed to the outside, heat can be transferred between the external heat exchanger 35 and the ambient air. An active damper 88 can open and close the vehicle's front grille. During cooling operation of the HVAC subsystem 11, the external heat exchanger 35 may be configured to condense refrigerant received from the internal condenser 33. In other words, the external heat exchanger 35 can function as an external condenser that condenses the refrigerant by transferring heat to the ambient air during cooling operation of the HVAC subsystem 11. During heating operation of the HVAC subsystem 11, the external heat exchanger 35 may be configured to evaporate refrigerant received from the water-cooled heat exchanger 70. In other words, the external heat exchanger 35 can function as an external evaporator that evaporates the refrigerant by absorbing heat from the ambient air during heating operation of the HVAC subsystem 11. In particular, the external heat exchanger 35 may be configured to exchange heat with ambient air forced by the cooling fan 75 to further increase the heat transfer rate between the external heat exchanger 35 and the ambient air.

[0081] The water-cooled heat exchanger 70 can be configured to transfer heat between the refrigerant circuit 21 of the HVAC subsystem 11, the battery coolant circuit 22 of the battery cooling subsystem 12, and the powertrain coolant circuit 23 of the powertrain cooling subsystem 13. Specifically, the water-cooled heat exchanger 70 can be disposed between the internal condenser 33 and the external heat exchanger 35 in the refrigerant circuit 21. The water-cooled heat exchanger 70 may include a first passage 71 fluidly connected to the powertrain coolant circuit 23, a second passage 72 fluidly connected to the battery coolant circuit 22, and a third passage 73 fluidly connected to the refrigerant circuit 21.

[0082] During heating operation of HVAC subsystem 11, water-cooled heat exchanger 70 can be configured to use heat transferred from power system cooling subsystem 13 to evaporate refrigerant received from internal condenser 33. In other words, during heating operation of HVAC subsystem 11, water-cooled heat exchanger 70 can function as an evaporator, which evaporates refrigerant by recovering waste heat from motor 51 and electrical / electronic components 52 of power system cooling subsystem 13.

[0083] During cooling operation of HVAC subsystem 11, water-cooled heat exchanger 70 can be configured to condense refrigerant received from internal condenser 33. Water-cooled heat exchanger 70 can function as a condenser, condensing the refrigerant by cooling the refrigerant using battery refrigerant circulating in battery refrigerant circuit 22 of battery cooling subsystem 12 and power system refrigerant circulating in power system refrigerant circuit 23 of power system cooling subsystem 13.

[0084] The heating-side expansion valve 16 may be located upstream of the water-cooled heat exchanger 70 on the refrigerant circuit 21. Specifically, the heating-side expansion valve 16 may be positioned between the internal condenser 33 and the water-cooled heat exchanger 70. During heating operation of the HVAC subsystem 11, the heating-side expansion valve 16 may be configured to regulate the flow rate or velocity of the refrigerant flowing into the water-cooled heat exchanger 70. The heating-side expansion valve 16 may be configured to expand the refrigerant received from the internal condenser 33 during heating operation of the HVAC subsystem 11.

[0085] According to an exemplary embodiment, the heating-side expansion valve 16 may be an electronic expansion valve (EXV) with a drive motor 16a. The drive motor 16a may have a shaft movable to open or close a throttle orifice defined in the valve body of the heating-side expansion valve 16, and the position of the shaft may be changed according to the rotation direction, degree of rotation, etc., of the drive motor 16a, thus changing the opening degree of the heating-side expansion valve 16 relative to the throttle orifice. The controller 100 may be configured to perform the operation of the drive motor 16a. The heating-side expansion valve 16 may be a fully open type EXV.

[0086] The opening degree of the heating-side expansion valve 16 can be changed by the controller 100. As the opening degree of the heating-side expansion valve 16 changes, the flow rate of refrigerant into the third passage 73 may change. During the heating operation of the HVAC subsystem 11, the heating-side expansion valve 16 can be operated by the controller 100.

[0087] A cooling-side expansion valve 15 can be disposed between the external heat exchanger 35 and the evaporator 31 on the refrigerant circuit 21. Since the cooling-side expansion valve 15 is located upstream of the evaporator 31, the flow rate or velocity of the refrigerant flowing into the evaporator 31 can be regulated. During cooling operation of the HVAC subsystem 11, the cooling-side expansion valve 15 can be configured to expand the refrigerant received from the external heat exchanger 35.

[0088] According to an exemplary embodiment, the cooling-side expansion valve 15 may be a thermostatic expansion valve (TXV) that senses the temperature and / or pressure of the refrigerant and adjusts the opening of the cooling-side expansion valve 15. Specifically, the cooling-side expansion valve 15 may be a TXV with a shut-off valve 15a that selectively prevents refrigerant from flowing into the internal passage of the cooling-side expansion valve 15, and the shut-off valve 15a may be a solenoid valve. The shut-off valve 15a may be opened or closed by the controller 100, thereby preventing or not preventing refrigerant from flowing into the cooling-side expansion valve 15.

[0089] When the shut-off valve 15a is open, refrigerant can flow into the cooling-side expansion valve 15, and when the shut-off valve 15a is closed, refrigerant flow into the cooling-side expansion valve 15 can be prevented. According to an exemplary embodiment, the shut-off valve 15a may be installed inside the valve body of the cooling-side expansion valve 15, thereby opening or closing the internal passage of the cooling-side expansion valve 15. According to another exemplary embodiment, the shut-off valve 15a may be located upstream of the cooling-side expansion valve 15, thereby selectively opening or closing the inlet of the cooling-side expansion valve 15.

[0090] When shut-off valve 15a is closed, the cooling-side expansion valve 15 may be blocked, so refrigerant may flow only into the battery cooler 37 and not into the cooling-side expansion valve 15 and evaporator 31. In other words, when shut-off valve 15a of the cooling-side expansion valve 15 is closed, the cooling operation of HVAC subsystem 11 may not be performed, and only the battery cooler 37 may be cooled or the heating operation of HVAC subsystem 11 may be performed. When shut-off valve 15a is open, refrigerant can flow into the cooling-side expansion valve 15 and evaporator 31. In other words, when shut-off valve 15a of the cooling-side expansion valve 15 is open, the cooling operation of HVAC subsystem 11 can be performed.

[0091] HVAC subsystem 11 may include an HVAC box 30 with an inlet and an outlet, and the HVAC box 30 may be configured to introduce air into the passenger compartment of the vehicle. An evaporator 31 and an internal condenser 33 may be located within the HVAC box 30. An air mixing door 34a may be provided between the evaporator 31 and the internal condenser 33, and a positive temperature coefficient (PTC) heater 34b may be provided downstream of the internal condenser 33.

[0092] HVAC subsystem 11 may also include a receiver 38 disposed between evaporator 31 and compressor 32 on refrigerant circuit 21, and the receiver 38 may be located downstream of evaporator 31. Receiver 38 may be configured to separate liquid refrigerant from refrigerant received from evaporator 31, thereby preventing liquid refrigerant from flowing into compressor 32.

[0093] HVAC subsystem 11 may further include a branch pipe 36 branching from refrigerant circuit 21. Branch pipe 36 may branch from an upstream point of cooling-side expansion valve 15 on refrigerant circuit 21 and connect to compressor 32. Battery cooler 37 may be fluidly connected to branch pipe 36, and battery cooler 37 may be configured to transfer heat between branch pipe 36 and battery coolant circuit 22, described later. In other words, battery cooler 37 may be configured to transfer heat between the refrigerant circulating in HVAC subsystem 11 and the battery coolant circulating in battery cooling subsystem 12.

[0094] Specifically, the battery cooler 37 may include a first channel 37a fluidly connected to a branch pipe 36 and a second channel 37b fluidly connected to a battery coolant circuit 22. The first channel 37a and the second channel 37b may be adjacent to or in contact with each other within the battery cooler 37, and the first channel 37a may be fluidly separated from the second channel 37b. Therefore, the battery cooler 37 may be configured to transfer heat between the battery coolant passing through the second channel 37b and the refrigerant passing through the first channel 37a. The branch pipe 36 may be fluidly connected to a reservoir 38, and the refrigerant passing through the branch pipe 36 may be received in the reservoir 38.

[0095] The cooler-side expansion valve 17 may be located upstream of the battery cooler 37 on the branch pipe 36. The cooler-side expansion valve 17 may be configured to regulate the flow rate or velocity of the refrigerant flowing into the battery cooler 37, and the cooler-side expansion valve 17 may be configured to expand the refrigerant received from the external heat exchanger 35.

[0096] According to an exemplary embodiment, the cooler-side expansion valve 17 may be an electronic expansion valve (EXV) with a drive motor 17a. The drive motor 17a may have a shaft movable to open or close an orifice defined in the valve body of the cooler-side expansion valve 17, and the position of the shaft may change depending on the rotation direction, degree of rotation, etc., of the drive motor 17a, thus changing the opening degree of the cooler-side expansion valve 17. In other words, the controller 100 may be configured to perform the operation of the drive motor 17a to change the opening degree of the cooler-side expansion valve 17. The cooler-side expansion valve 17 may be a fully open EXV.

[0097] When the opening degree of the cooler-side expansion valve 17 changes, the flow rate of refrigerant flowing into the battery cooler 37 may change. For example, when the opening degree of the cooler-side expansion valve 17 is greater than a reference opening degree, the flow rate of refrigerant flowing into the battery cooler 37 may increase compared to the reference flow rate, and when the opening degree of the cooler-side expansion valve 17 is less than the reference opening degree, the flow rate of refrigerant flowing into the battery cooler 37 may be similar to the reference flow rate or may be relatively reduced compared to the reference flow rate. In particular, the reference opening degree may be the opening degree of the cooler-side expansion valve 17 used to maintain the target evaporator temperature, and the reference flow rate may be the flow rate of refrigerant flowing into the battery cooler 37 when the cooler-side expansion valve 17 is opened to the reference opening degree. In other words, when the cooler-side expansion valve 17 is opened to the reference opening degree, the refrigerant may flow into the battery cooler 37 at the corresponding reference flow rate.

[0098] Since the opening of the cooler-side expansion valve 17 is adjusted by the controller 100, the flow rate of refrigerant flowing into the battery cooler 37 can be varied, and therefore the flow rate of refrigerant flowing into the evaporator 31 can also be varied. By adjusting the opening of the cooler-side expansion valve 17, the refrigerant can be distributed into the evaporator 31 and the battery cooler 37 at a predetermined rate, so the cooling of the HVAC subsystem 11 and the cooling of the battery cooler 37 can be performed simultaneously or selectively.

[0099] HVAC subsystem 11 may also include a refrigerant bypass line 39 connecting a downstream point of the water-cooled heat exchanger 70 to a branch line 36. The inlet of the refrigerant bypass line 39 may be connected to a downstream point of the water-cooled heat exchanger 70, and the outlet of the refrigerant bypass line 39 may be connected to the branch line 36. Specifically, the inlet of the refrigerant bypass line 39 may be connected to a point between the water-cooled heat exchanger 70 and the external heat exchanger 35, and the outlet of the refrigerant bypass line 39 may be connected to a point between the battery cooler 37 and the compressor 32 on the branch line 36. A first three-way valve 61 may be located at the connection between the inlet of the refrigerant bypass line 39 and the refrigerant circuit 21.

[0100] The first three-way valve 61 can be installed between the external heat exchanger 35 and the water-cooled heat exchanger 70 on the refrigerant circuit 21. When the first three-way valve 61 is switched to open the inlet of the refrigerant bypass pipe 39, the refrigerant passing through the third passage 73 of the water-cooled heat exchanger 70 can flow into the compressor 32 through the refrigerant bypass pipe 39. In other words, when the inlet of the refrigerant bypass pipe 39 is opened by switching the first three-way valve 61, the refrigerant can bypass the external heat exchanger 35. When the first three-way valve 61 is switched to close the inlet of the refrigerant bypass pipe 39, the refrigerant passing through the third passage 73 of the water-cooled heat exchanger 70 can flow into the external heat exchanger 35 without passing through the refrigerant bypass pipe 39. In other words, when the inlet of the refrigerant bypass pipe 39 is closed by switching the first three-way valve 61, the refrigerant can pass through the external heat exchanger 35.

[0101] The controller 100 can be configured to perform corresponding operations on the shut-off valve 15a of the cooling-side expansion valve 15, the heating-side expansion valve 16, the cooler-side expansion valve 17, the compressor 32, etc., and thus the overall operation of the HVAC subsystem 11 can be performed by the controller 100. According to an exemplary embodiment, the controller 100 can be a fully automatic temperature control (FATC) system.

[0102] When the HVAC subsystem 11 is running in cooling mode, the shut-off valve 15a of the cooling-side expansion valve 15 can be opened, and the refrigerant can circulate sequentially through the compressor 32, the internal condenser 33, the heating-side expansion valve 16, the third passage 73 of the water-cooled heat exchanger 70, the external heat exchanger 35, the cooling-side expansion valve 15, and the evaporator 31.

[0103] When the HVAC subsystem 11 is operating in heating mode, the shut-off valve 15a of the cooling-side expansion valve 15 can be closed, allowing the refrigerant to circulate sequentially through the compressor 32, internal condenser 33, heating-side expansion valve 16, third passage 73 of the water-cooled heat exchanger 70, external heat exchanger 35, cooling-side expansion valve 17, first passage 37a of the battery cooler 37, and compressor 32. During heating operation of the HVAC subsystem 11, when the shut-off valve 15a of the cooling-side expansion valve 15 is closed and the inlet of the refrigerant bypass pipe 39 is opened by switching the first three-way valve 61, the refrigerant can circulate sequentially through the compressor 32, internal condenser 33, heating-side expansion valve 16, third passage 73 of the water-cooled heat exchanger 70, refrigerant bypass pipe 39, and compressor 32.

[0104] The battery cooling subsystem 12 can be configured to cool the battery pack 41 using battery coolant circulating in the battery coolant circuit 22. The battery coolant circuit 22 can be fluidly connected to the battery pack 41, heater 42, battery cooler 37, first battery-side pump 44, battery radiator 43, reservoir 48, and second battery-side pump 45. Figure 1 In the process, the battery coolant can pass through the battery coolant circuit 22 in sequence through the battery pack 41, heater 42, battery cooler 37, first battery side pump 44, battery radiator 43, storage tank 48, water-cooled heat exchanger 70 and second battery side pump 45.

[0105] The battery pack 41 may have a coolant channel through which battery coolant flows inside or outside the battery pack 41, and the battery coolant circuit 22 may be fluidly connected to the coolant channel of the battery pack 41. A heater 42 may be disposed between the battery cooler 37 and the battery pack 41, and the heater 42 may be configured to heat the battery coolant circulating in the battery coolant circuit 22, thereby heating the coolant. According to an exemplary embodiment, the heater 42 may be a water heater that heats the coolant by heat exchange with a high-temperature fluid. According to another exemplary embodiment, the heater 42 may be an electric heater.

[0106] The battery radiator 43 may be arranged adjacent to the front grille of the vehicle, and the battery radiator 43 may be cooled by ambient air forced by the cooling fan 75. The battery radiator 43 may be adjacent to an external heat exchanger 35. A first battery-side pump 44 may circulate battery coolant through at least a portion of the battery coolant circuit 22, and a second battery-side pump 45 may circulate battery coolant through at least a portion of the battery coolant circuit 22.

[0107] The first battery-side pump 44 can be located upstream of the battery radiator 43 in the battery coolant circuit 22. The first battery-side pump 44 can be configured to force-pump battery coolant to the inlet of the battery radiator 43, thereby allowing battery coolant to pass through the battery radiator 43. The second battery-side pump 45 can be located upstream of the battery pack 41 in the battery coolant circuit 22. The second battery-side pump 45 can be configured to force-pump battery coolant into the battery pack 41, thereby allowing battery coolant to pass through the battery pack 41.

[0108] The first battery-side pump 44 and the second battery-side pump 45 can be configured to operate individually and selectively based on the heating and charging status of the battery pack 41, the operating status of the HVAC subsystem 11, etc. A reservoir 48 can be located between the outlet of the battery radiator 43 and the inlet of the second battery-side pump 45.

[0109] The battery cooling subsystem 12 may also include a first battery bypass conduit 46 that allows the battery coolant to bypass the battery radiator 43. The first battery bypass conduit 46 may be directly connected to the upstream point of the battery radiator 43 and the downstream point of the battery radiator 43 on the battery coolant circuit 22.

[0110] The inlet of the first battery bypass pipe 46 can be connected to the point between the inlets of the battery cooler 37 and the battery radiator 43 on the battery coolant circuit 22. Specifically, the inlet of the first battery bypass pipe 46 can be connected to the point between the inlet of the battery cooler 37 and the inlet of the first battery side pump 44 on the battery coolant circuit 22.

[0111] The outlet of the first battery bypass pipe 46 can be connected to the point between the outlets of the battery cooler 37 and the battery radiator 43 on the battery coolant circuit 22. Specifically, the outlet of the first battery bypass pipe 46 can be connected to the point between the inlet of the second battery-side pump 45 and the outlet of the reservoir 48 on the battery coolant circuit 22.

[0112] As the battery coolant flows from the outlet of the battery cooler 37 through the first battery bypass pipe 46 to the inlet of the second battery side pump 45, the battery coolant can bypass the first battery side pump 44, the battery radiator 43, the reservoir 48 and the water-cooled heat exchanger 70, and thus the battery coolant through the first battery bypass pipe 46 can be circulated through the second battery side pump 45 in the order of battery pack 41, heater 42 and battery cooler 37.

[0113] The battery cooling subsystem 12 may also include a second battery bypass conduit 47 that allows the battery coolant to bypass the battery pack 41, heater 42, and battery cooler 37. The second battery bypass conduit 47 may be directly connected to the downstream point of the battery cooler 37 on the battery coolant circuit 22 and the upstream point of the battery pack 41.

[0114] The inlet of the second battery bypass pipe 47 can be connected to the point between the outlet of the first battery bypass pipe 46 on the battery coolant circuit 22 and the outlet of the battery radiator 43. Specifically, the inlet of the second battery bypass pipe 47 can be connected to the point between the outlet of the first battery bypass pipe 46 on the battery coolant circuit 22 and the outlet of the reservoir 48.

[0115] The outlet of the second battery bypass pipe 47 can be connected to the point between the inlet of the first battery bypass pipe 46 and the inlet of the battery radiator 43 on the battery coolant circuit 22. Specifically, the outlet of the second battery bypass pipe 47 can be connected to the point between the inlet of the first battery bypass pipe 46 and the inlet of the first battery side pump 44 on the battery coolant circuit 22. As battery coolant flows from the outlet of the battery radiator 43 into the inlet of the first battery side pump 44 through the second battery bypass pipe 47, the battery coolant can bypass the battery pack 41, heater 42, and battery cooler 37. Therefore, the battery coolant through the second battery bypass pipe 47 can circulate through the first battery side pump 44 in the order of battery radiator 43, reservoir 48, and water-cooled heat exchanger 70. The first battery bypass pipe 46 and the second battery bypass pipe 47 can be parallel to each other.

[0116] The battery cooling subsystem 12 may also include a second three-way valve 62 disposed at the inlet of the first battery bypass pipe 46. In other words, the second three-way valve 62 may be disposed at the junction between the inlet of the first battery bypass pipe 46 and the battery coolant circuit 22. When the second three-way valve 62 is switched to open the inlet of the first battery bypass pipe 46, a portion of the battery coolant (from the battery cooler 37) can pass through the first battery bypass pipe 46, allowing it to bypass the battery radiator 43, while the remaining battery coolant (from the battery radiator 43) can pass through the second battery bypass pipe 47, allowing it to bypass the battery pack 41, the heater 42, and the battery cooler 37.

[0117] In other words, when the inlet of the first battery bypass pipe 46 is opened by switching the second three-way valve 62, the second three-way valve 62, the first battery bypass pipe 46, and the second battery bypass pipe 47 divide the battery coolant circuit 22 into two independent circulation circuits that are fluidly separated from each other. The battery coolant passing through the first battery bypass pipe 46 can bypass the first battery side pump 44, the battery radiator 43, the reservoir 48, and the water-cooled heat exchanger 70, and circulate sequentially through the battery pack 41, the heater 42, and the battery cooler 37 via the second battery side pump 45. Similarly, the battery coolant passing through the second battery bypass pipe 47 can bypass the second battery side pump 45, the battery pack 41, the heater 42, and the battery cooler 37, and circulate sequentially through the battery radiator 43, the reservoir 48, and the water-cooled heat exchanger 70 via the first battery side pump 44.

[0118] When the second three-way valve 62 is switched to close the inlet of the first battery bypass pipe 46, the battery coolant can bypass the first battery bypass pipe 46. In other words, when the inlet of the first battery bypass pipe 46 is closed by switching the second three-way valve 62, the battery coolant can circulate through the battery coolant circuit 22.

[0119] The battery cooling subsystem 12 can be operated by the battery management system 110. The battery management system 110 can be configured to monitor the state of the battery pack 41 and, in response to determining that the temperature of the battery pack 41 is greater than or equal to a predetermined temperature, perform cooling of the battery pack 41. The battery management system 110 can be configured to send a command to the controller 100 for cooling the battery pack 41, so the controller 100 can be configured to operate the compressor 32 to be started and operate the chiller-side expansion valve 17 to open. When the operation of the HVAC subsystem 11 is not required during the cooling operation of the battery pack 41, the controller 100 can be configured to operate the cooling-side expansion valve 15 to close. Furthermore, the battery management system 110 can be configured to perform operation of the first battery-side pump 44, operation of the second battery-side pump 45, and switching of the second three-way valve 62 as needed, so that the battery coolant can bypass the battery radiator 43 and circulate through the battery pack 41 and the battery cooler 37.

[0120] The powertrain cooling subsystem 13 can be configured to cool the powertrain motor 51 and electrical / electronic components 52 using powertrain coolant circulated through the powertrain coolant circuit 23. The powertrain coolant circuit 23 can be fluidly connected to the powertrain radiator 53, reservoir 56, powertrain side pump 54, electrical / electronic components 52, motor 51, and the first passage 71 of the water-cooled heat exchanger 70. Figure 1In this process, the power system coolant can pass through the power system coolant circuit 23 in the order of power system radiator 53, liquid tank 56, power system side pump 54, electrical / electronic components 52, motor 51 and water-cooled heat exchanger 70 first passage 71.

[0121] The electric motor 51 may have a coolant passage through which powertrain coolant flows inside or outside the motor 51, and the powertrain coolant circuit 23 may be fluidly connected to the coolant passage of the electric motor 51. The electrical / electronic component 52 may be one or more electrical / electronic components associated with the drive of the electric motor 51, such as an inverter, on-board charger (OBC), and low-voltage DC-DC converter (LDC). The electrical / electronic component 52 may have a coolant passage through which coolant flows inside or outside the electrical / electronic component 52, and the powertrain coolant circuit 23 may be fluidly connected to the coolant passage of the electrical / electronic component 52.

[0122] The powertrain radiator 53 can be arranged adjacent to the front grille of the vehicle, and the powertrain radiator 53 can be cooled by ambient air forced in by the cooling fan 75. The external heat exchanger 35, battery radiator 43, and powertrain radiator 53 can be arranged adjacent to each other at the front of the vehicle, so that the external heat exchanger 35, battery radiator 43, and powertrain radiator 53 can contact and exchange heat with the ambient air. The cooling fan 75 can be located at the rear of the external heat exchanger 35, battery radiator 43, and powertrain radiator 53.

[0123] The powertrain side pump 54 can be located upstream of the motor 51 and electrical / electronic components 52, and the powertrain side pump 54 allows the powertrain coolant to circulate in the powertrain coolant circuit 23. The powertrain cooling subsystem 13 may also include a powertrain bypass pipe 55, which allows the powertrain coolant to bypass the powertrain radiator 53. The powertrain bypass pipe 55 can be directly connected to the upstream and downstream points of the powertrain radiator 53 on the powertrain coolant circuit 23, so that the powertrain coolant from the outlet of the motor 51 can be introduced into the inlet of the powertrain side pump 54 through the powertrain bypass pipe 55, and thus the coolant can bypass the powertrain radiator 53.

[0124] The inlet of the powertrain bypass pipe 55 can be connected to the point between the reservoir 56 on the powertrain coolant circuit 23 and the electrical / electronic component 52. Specifically, the inlet of the powertrain bypass pipe 55 can be connected to the point between the reservoir 56 on the powertrain coolant circuit 23 and the inlet of the powertrain side pump 54. The outlet of the powertrain bypass pipe 55 can be connected to the point between the motor 51 on the powertrain coolant circuit 23 and the powertrain radiator 53.

[0125] The powertrain cooling subsystem 13 may also include a third three-way valve 63 located at the inlet of the powertrain bypass pipe 55. When the third three-way valve 63 is switched to open the inlet of the powertrain bypass pipe 55, the powertrain coolant can bypass the powertrain radiator 53 through the powertrain bypass pipe 55. Therefore, the powertrain coolant can circulate sequentially through the motor 51, the first passage 71 of the water-cooled heat exchanger 70, the powertrain bypass pipe 55, the powertrain side pump 54, and the electrical / electronic components 52. When the third three-way valve 63 is switched to close the inlet of the powertrain bypass pipe 55, the powertrain coolant can bypass the powertrain bypass pipe 55, and the powertrain coolant can circulate sequentially through the motor 51, the first passage 71 of the water-cooled heat exchanger 70, the powertrain radiator 53, the reservoir 56, the powertrain side pump 54, and the electrical / electronic components 52.

[0126] The reservoir 56 may be located downstream of the powertrain radiator 53. Specifically, the reservoir 56 may be positioned between the powertrain radiator 53 and the third three-way valve 63 on the powertrain coolant circuit 23. In the powertrain cooling subsystem 13, the switching of the third three-way valve 63 and the operation of the powertrain-side pump 54 may be controlled by the controller 100. When the vehicle travels a predetermined distance or the battery is being rapidly charged, the heat dissipated from powertrain components such as the electric motor 51 and electrical / electronic components 52 may increase relatively.

[0127] A vehicle thermal management system according to an exemplary embodiment of the present invention may include: an internal temperature sensor 81 configured to measure the internal temperature of the passenger compartment; an external temperature sensor or ambient temperature sensor 82 configured to measure the ambient temperature of the vehicle; a solar radiation sensor 83 configured to measure the amount of solar radiation transmitted to the vehicle; a first coolant temperature sensor 84 configured to measure the temperature of the powertrain coolant; and a second coolant temperature sensor 85 configured to measure the temperature of the battery coolant.

[0128] An interior temperature sensor 81 can be positioned within the passenger compartment to measure the interior temperature in real time. The interior temperature measured by the interior temperature sensor 81 can be used for optimal control of the HVAC subsystem 11. An ambient temperature sensor 81 can be positioned near the front grille of the vehicle to measure the ambient temperature of the vehicle, and the ambient temperature measured by the ambient temperature sensor 82 can be used for optimal control of the HVAC subsystem 11.

[0129] A solar radiation sensor 83 can be mounted on the windshield or roof of the vehicle to measure the amount of solar radiation delivered to the vehicle. The amount of solar radiation measured by the solar radiation sensor 83 can be used for optimal control of the HVAC subsystem 11. A first coolant temperature sensor 84 can be positioned downstream of powertrain components 51 and 52 along the flow direction of the powertrain coolant in the powertrain coolant circuit 23. Specifically, the first coolant temperature sensor 84 can be positioned between powertrain components 51 and 52 in the powertrain coolant circuit 23 and the first passage 71 of the water-cooled heat exchanger 70. The first coolant temperature sensor 84 can be configured to measure the temperature of the powertrain coolant that has exchanged heat with the powertrain components 51 and 52. In other words, the first coolant temperature sensor 84 can be configured to measure the temperature of the powertrain coolant that has absorbed heat from the powertrain components 51 and 52.

[0130] The second coolant temperature sensor 85 can be disposed downstream of the battery radiator 43 along the flow direction of the battery coolant in the battery coolant circuit 22. Specifically, the second coolant temperature sensor 85 can be disposed between the battery radiator 43 and the second passage 72 of the water-cooled heat exchanger 70 in the battery coolant circuit 22. The second coolant temperature sensor 85 can be configured to measure the temperature of the battery coolant that has exchanged heat with the battery radiator 43. In other words, the second coolant temperature sensor 85 can be configured to measure the temperature of the battery coolant that has absorbed heat from the ambient air.

[0131] The controller 100 can be configured to use an internal temperature sensor 81, an ambient temperature sensor 82, a solar radiation sensor 83, a first coolant temperature sensor 84, a second coolant temperature sensor 85, a humidity sensor, a high-pressure side pressure sensor, a low-pressure side pressure sensor, an evaporator temperature sensor, etc., to perform the operation of the HVAC subsystem 11, the battery cooling subsystem 12, and the powertrain cooling subsystem 13.

[0132] Figures 2 to 4 A method for controlling the heating of a vehicle thermal management system according to an exemplary embodiment of the present invention is shown.

[0133] according to Figure 2 and Figure 3 In the exemplary embodiment shown, the heating operation of the HVAC subsystem 11 can be performed by allowing the refrigerant circulating in the HVAC subsystem 11 to absorb heat from the ambient air and / or by absorbing waste heat from the power system components 51 and 52 based on the heat output Q of the power system components 51 and 52.

[0134] according to Figure 4In the exemplary embodiment shown, the heating operation of the HVAC subsystem 11 can be performed based on the heat load of the HVAC subsystem 11 by absorbing heat from the power system components 51 and 52 and / or ambient air through the refrigerant circulating in the HVAC subsystem 11.

[0135] Figure 2 A flowchart illustrating a method for controlling heating in a vehicle thermal management system according to an exemplary embodiment of the present invention is shown. Controller 100 may be configured to determine whether heating of the passenger compartment is required (S1). Controller 100 may be configured to determine the need for heating of the passenger compartment based on ambient air temperature measured by ambient temperature sensor 82, interior temperature measured by interior temperature sensor 81, desired heating temperature set by the user (occupant), and the temperature of air (already passed through the evaporator) measured by evaporator temperature sensor, etc. For example, controller 100 may be configured to determine the need for heating of the passenger compartment in response to determining that the ambient air temperature is lower than a predetermined reference ambient air temperature.

[0136] As another example, controller 100 can be configured to determine that passenger compartment heating is needed when the internal temperature is lower than the ambient air temperature. As another example, controller 100 can be configured to determine that passenger compartment heating is needed in response to determining that the internal set temperature is higher than the internal temperature. As another example, controller 100 can be configured to determine that passenger compartment heating is needed in response to determining that the temperature of the air that has passed through the evaporator is lower than a reference air temperature. In response to determining that passenger compartment heating is needed, controller 100 can be configured to start compressor 32 (S2). The RPM of compressor 32 can be determined based on the internal temperature setting, etc., and can vary over time.

[0137] Controller 100 can be configured to determine whether the heat generation Q from power system components 51 and 52 is greater than or equal to a reference heat generation Q. R (S3). Reference calorific value Q R This can be defined as the heat generated by absorbing heat Q from powertrain components 51 and 52 to evaporate the refrigerant circulating in the HVAC subsystem 11. For example, when the vehicle travels a predetermined distance within a predetermined time period or is fast-charging, the heat generated Q can increase to a level higher than a reference heat generated Q. R Furthermore, when the vehicle is initially started, the heat generation Q can be less than the reference heat generation Q. R .

[0138] In response to determining that the heat generation Q from the powertrain components is greater than or equal to the reference heat generation Q RThe controller 100 can be configured to start the powertrain-side pump 54 and stop the first battery-side pump 44 (S4), thereby preventing battery coolant from passing through the battery radiator 43 and thus preventing the battery coolant from exchanging heat with the ambient air through the battery radiator 43. Therefore, the refrigerant through the third passage 73 of the water-cooled heat exchanger 70 can exchange heat only with the powertrain coolant through the first passage 71 of the water-cooled heat exchanger 70, without exchanging heat with the battery coolant. The powertrain coolant through the first passage 71 of the water-cooled heat exchanger 70 can be heated by heat generated by the powertrain components. In the water-cooled heat exchanger 70, the refrigerant can exchange heat with the heated powertrain coolant and absorb heat from the powertrain components (waste heat recovery), allowing it to be sufficiently heated and evaporated to meet the heat load of the HVAC subsystem 11.

[0139] In other words, when the calorific value Q is greater than or equal to the reference calorific value Q R At this time, the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70 can absorb heat from the powertrain components 51 and 52, thereby being fully heated and evaporated. When the ambient air temperature is less than or equal to the temperature of the refrigerant heated by the water-cooled heat exchanger 70, the refrigerant can be cooled by the battery coolant that has already exchanged heat with the ambient air through the battery radiator 43. To prevent the battery coolant from exchanging heat with the ambient air through the battery radiator 43, the operation of the first battery-side pump 44 can be stopped. When the powertrain-side pump 54 is started, the powertrain coolant can circulate normally through the powertrain coolant circuit 23.

[0140] In response to determining that the heat generated Q from power system components 51 and 52 is less than the reference heat generated Q R The controller 100 can be configured to activate the powertrain-side pump 54 and the first battery-side pump 44 (S5), thereby allowing powertrain coolant to pass through the powertrain radiator 53 and battery coolant to pass through the battery radiator 43. Through heat exchange with the powertrain coolant passing through the first passage 71 of the water-cooled heat exchanger 70 and the battery coolant passing through the second passage 72 of the water-cooled heat exchanger 70, the cryogenic refrigerant passing through the third passage 73 of the water-cooled heat exchanger 70 can evaporate.

[0141] Specifically, the powertrain coolant can absorb heat from the ambient air and from powertrain components 51 and 52 through the powertrain radiator 53, and the battery coolant can absorb heat from the ambient air through the battery radiator 43. In other words, when the heat generation Q is less than the reference heat generation Q... R At that time, the refrigerant circulating in the HVAC subsystem 11 can evaporate in the water-cooled heat exchanger 70 by recovering waste heat from power system components 51 and 52 and absorbing heat from the ambient air.

[0142] According to an alternative exemplary embodiment, after the compressor 32 is started (i.e., after step S2) or when the calorific value Q is greater than or equal to the reference calorific value Q in S3. R At this time, the inlet of the powertrain bypass pipe 55 can be opened by switching the third three-way valve 63, allowing the powertrain coolant to bypass the powertrain radiator 53, and thus preventing the powertrain coolant from exchanging heat with the ambient air through the powertrain radiator 53. This is because when the ambient air temperature is relatively low, the powertrain coolant exchanging heat with the ambient air may interfere with the evaporation of the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70.

[0143] Figure 3 The specific implementation is shown. Figure 2 A flowchart of a method for controlling the heating of a vehicle thermal management system, according to an embodiment. (Refer to...) Figure 3 The controller 100 can be configured to determine whether heating of the passenger compartment is required (S11). In response to determining that heating of the passenger compartment is required, the controller 100 can be configured to start the compressor 32 (S12). The controller 100 can be configured to monitor the temperature T1 of the powertrain coolant as measured by the first coolant temperature sensor 84 and the temperature T2 of the battery coolant as measured by the second coolant temperature sensor 85 (S13).

[0144] The controller 100 can be configured to calculate the temperature difference (T1-T2) between the powertrain coolant temperature T1 and the battery coolant temperature T2, and determine whether the temperature difference (T1-T2) is greater than or equal to a reference value T. R (S14). Reference value T R This can correspond to the reference calorific value Q. R In response to the determination that the temperature difference (T1-T2) between the powertrain coolant temperature T1 and the battery coolant temperature T2 is greater than or equal to the reference value T... R The controller 100 can be configured to determine that the heat generated Q from the powertrain components 51 and 52 is relatively high, and in response to determining that the temperature difference (T1-T2) between the powertrain coolant temperature T1 and the battery coolant temperature T2 is less than a reference value T R The controller 100 can be configured to determine that the heat generation Q from the power system components 51 and 52 is relatively low.

[0145] In response to the determination that the temperature difference (T1-T2) between the powertrain coolant temperature T1 and the battery coolant temperature T2 is greater than or equal to the reference value T R The controller 100 can be configured to determine that the heat generation Q from the power system components 51 and 52 is greater than or equal to a reference heat generation Q. RThe controller 100 can be configured to start the powertrain-side pump 54 and stop the first battery-side pump 44 (S15), thereby preventing battery coolant from passing through the battery radiator 43 and thus preventing heat exchange between the battery coolant and ambient air through the battery radiator 43. The low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70 can exchange heat only with the powertrain coolant through the first passage 71 of the water-cooled heat exchanger 70, and not with the battery coolant.

[0146] The power system coolant passing through the first passage 71 of the water-cooled heat exchanger 70 can be heated by the heat generated by the power system components. In the water-cooled heat exchanger 70, the low-temperature refrigerant can exchange heat with the heated power system coolant and absorb heat from the power system components (waste heat recovery), allowing it to be sufficiently heated and evaporated to meet the heat load of the HVAC subsystem 11. In other words, when the temperature difference (T1-T2) between the power system coolant temperature T1 and the battery coolant temperature T2 is greater than or equal to the reference value T... R At that time, the refrigerant circulating in the HVAC subsystem 11 can be fully evaporated in the water-cooled heat exchanger 70 by recovering waste heat from the power system components.

[0147] When the temperature difference (T1-T2) between the powertrain coolant temperature T1 and the battery coolant temperature T2 is less than the reference value T R At that time, the controller 100 can be configured to determine that the heat generated Q from the power system components 51 and 52 is less than the reference heat generated Q. R The controller 100 can be configured to activate the powertrain-side pump 54 and the first battery-side pump 44 (S16), thereby allowing powertrain coolant to pass through the powertrain radiator 53 and battery coolant to pass through the battery radiator 43. The low-temperature refrigerant passing through the third passage 73 of the water-cooled heat exchanger 70 can exchange heat with the powertrain coolant passing through the first passage 71 of the water-cooled heat exchanger 70, and with the battery coolant passing through the second passage 72 of the water-cooled heat exchanger 70.

[0148] The powertrain coolant can absorb heat from the ambient air and from powertrain components 51 and 52 through the powertrain radiator 53, and the battery coolant can absorb heat from the ambient air through the battery radiator 43. In other words, when the temperature difference (T1-T2) between the powertrain coolant temperature T1 and the battery coolant temperature T2 is less than the reference value T... R At this time, the refrigerant circulating in the HVAC subsystem 11 can be fully evaporated in the water-cooled heat exchanger 70 by recovering waste heat from power system components and absorbing heat from ambient air. The method can return to step S13 after step S16.

[0149] After the powertrain side pump 54 and the first battery side pump 44 are started, the cooling fan 75 can be started or the active damper 88 can be opened to absorb more heat from the ambient air. However, when the ambient air temperature is low, the cooling fan 75 can be stopped or the active damper 88 can be closed.

[0150] According to an alternative exemplary embodiment, after compressor 32 is started (i.e., after step S12) or when the temperature difference value (T1-T2) is greater than or equal to the reference value T in step S14. R At this time, the inlet of the powertrain bypass pipe 55 can be opened by switching the third three-way valve 63, allowing the powertrain coolant to bypass the powertrain radiator 53, and thus preventing the powertrain coolant from exchanging heat with the ambient air through the powertrain radiator 53. This is because when the ambient air temperature is relatively low, the powertrain coolant exchanging heat with the ambient air may interfere with the evaporation of the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70.

[0151] Figure 4 A flowchart of a method for controlling the heating of a vehicle thermal management system according to another exemplary embodiment of the present invention is shown.

[0152] The controller 100 can be configured to determine whether heating of the passenger compartment is required (S21). In response to determining that heating of the passenger compartment is required, the controller 100 can be configured to start the compressor 32 (S22). According to an exemplary embodiment, after the compressor 32 is started, the controller 100 can be configured to operate a third three-way valve 63 to close the inlet of the powertrain bypass pipe 55, so that powertrain coolant can pass through the powertrain side pump 54 through the powertrain radiator 53 and powertrain components 51 and 52.

[0153] The controller 100 can be configured to determine whether the heat load HL required for the heating operation of the HVAC subsystem 11 is lower than or equal to a first reference load HL1 (S23). The first reference load HL1 can be a reference load used to determine whether the heat load is low, and can vary depending on the vehicle's driving conditions, internal and external conditions, the heating operation conditions of the HVAC subsystem 11, vehicle specifications, etc.

[0154] When the heat load HL is less than or equal to the first reference load HL1, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet the low load conditions. When the heating operating conditions of the HVAC subsystem 11 meet the low load conditions, the heat generation Q from the power system components 51 and 52 may be relatively low. Even when the refrigerant circulating in the HVAC subsystem 11 absorbs heat from the power system components 51 and 52, the heat capacity of the HVAC subsystem 11 may be relatively low, and therefore there is no heat increment in the HVAC subsystem 11.

[0155] When the heat load HL is less than or equal to the first reference load HL1, the controller 100 can be configured to stop the powertrain-side pump 54 and only start the first battery-side pump 44 (S24), allowing the refrigerant circulating in the HVAC subsystem 11 to exchange heat with the battery coolant absorbing heat from the ambient air. When the first battery-side pump 44 is started, the battery coolant can pass through the battery radiator 43, allowing the battery coolant to absorb heat from the ambient air, and thus, the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70 can be heated and evaporated by the battery coolant absorbing heat from the ambient air. When the powertrain-side pump 54 is stopped, the powertrain coolant may not circulate through the powertrain coolant circuit 23, and the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70 may not exchange heat with the powertrain coolant. In particular, the first battery-side pump 44 can operate at a relatively low RPM set based on the heat load (i.e., the low load of the HVAC subsystem 11).

[0156] Conversely, if the controller 100 stops the first battery-side pump 44 and only starts the powertrain-side pump 54 in step S24, the refrigerant can exchange heat with the powertrain coolant in the water-cooled heat exchanger 70. However, specifically, because the powertrain coolant circuit 23 has a relatively complex flow path, the flow rate of the powertrain coolant circulated by the powertrain-side pump 54 is lower than the flow rate of the battery coolant circulated by the first battery-side pump 44. If the first battery-side pump 44 is stopped in step S24 and only the powertrain-side pump 54 is started, the flow rate of the powertrain coolant may be relatively low, and therefore the heat exchange performance of the refrigerant in the water-cooled heat exchanger 70 will be relatively reduced. Taking this into consideration, only the first battery-side pump 44 can be started in step S24, thereby improving the heat exchange performance of the refrigerant and reducing power consumption.

[0157] When the heat load HL is higher than the first reference load HL1 in step S23, the controller 100 can be configured to determine whether the heat load HL is higher than the first reference load HL1 and lower than or equal to the second reference load HL2 (S25). The second reference load HL2 is a reference load used to determine whether the heat load is a medium load, and the second reference load HL2 can be higher than the first reference load HL1. The second reference load HL2 can vary according to the vehicle's driving conditions and internal and external conditions, the heating operation conditions of the HVAC subsystem 11, the vehicle's specifications, etc.

[0158] When the heat load HL is higher than the first reference load HL1 and lower than or equal to the second reference load HL2, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet the medium load conditions. When the heating operating conditions of the HVAC subsystem 11 meet the medium load conditions, the heat generation Q from the power system components 51 and 52 can be relatively increased compared to the low load conditions.

[0159] When the heat load HL is higher than the first reference load HL1 and lower than or equal to the second reference load HL2, the controller 100 can be configured to start the first battery-side pump 44 and the powertrain-side pump 54 (S26), so that the refrigerant circulating in the HVAC subsystem 11 can exchange heat with the battery coolant that absorbs heat from the ambient air, and with the powertrain coolant that absorbs heat from the powertrain components 51 and 52 and the ambient air. When the first battery-side pump 44 is started, the battery coolant can pass through the battery radiator 43, so that the battery coolant can absorb heat from the ambient air through the battery radiator 43. Therefore, the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70 can be heated and evaporated by the battery coolant that absorbs heat from the ambient air.

[0160] When the powertrain-side pump 54 starts, the powertrain coolant can pass through powertrain components 51 and 52 and the powertrain radiator 53, allowing the coolant to absorb heat from the powertrain components 51 and 52 and from the ambient air through the powertrain radiator 53. Therefore, the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70 can be heated and evaporated by the powertrain coolant absorbing heat from the powertrain components 51 and 52 and the ambient air. Specifically, the first battery-side pump 44 and the powertrain-side pump 54 can operate at a relatively moderate RPM based on the heat load (i.e., the moderate load of the HVAC subsystem 11).

[0161] In response to the determination in step S25 that the heat load HL is higher than the second reference load HL2, the controller 100 may be configured to determine whether the heat load HL exceeds the second reference load HL2 and whether the heat generated Q from the power system components 51 and 52 is less than the heat capacity W generated by the heating operation of the HVAC subsystem 11. hp (S27). The heat generation Q can be calculated using the first coolant temperature sensor 84 and flow sensor installed on the power system coolant circuit 23, and the heat capacity W can be calculated using the coefficient of performance (COP) of the HVAC subsystem 11, the power consumption of the compressor 32, etc. hp .

[0162] When the heat load HL exceeds the second reference load HL2 and the heat output Q is less than the heat capacity W hpAt that time, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet the high load conditions and that the heat output Q of the power system components 51 and 52 alone is insufficient to evaporate the refrigerant circulating in the HVAC subsystem 11.

[0163] When the heat load HL exceeds the second reference load HL2 and the heat output Q is less than the heat capacity W hp At this time, the controller 100 can be configured to activate the first battery-side pump 44 and the powertrain-side pump 54 (S28), so that the refrigerant circulating in the HVAC subsystem 11 can exchange heat with the battery coolant that absorbs heat from the ambient air, and with the powertrain coolant that absorbs heat from the powertrain components 51 and 52 and the ambient air. When the first battery-side pump 44 is activated, the battery coolant can pass through the battery radiator 43, allowing the battery coolant to absorb heat from the ambient air. Therefore, the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70 can be heated and evaporated by the battery coolant that absorbs heat from the ambient air.

[0164] When the powertrain side pump 54 starts, the powertrain coolant can absorb heat from the powertrain components 51 and 52 and the powertrain radiator 53, thus absorbing heat from the ambient air through the powertrain components 51 and 52 and from the ambient air through the powertrain radiator 53. Consequently, the low-temperature refrigerant through the third passage 73 of the water-cooled heat exchanger 70 can be heated and evaporated by the powertrain coolant absorbing heat from the powertrain components 51 and 52 and the ambient air. Specifically, the first battery side pump 44 and the powertrain side pump 54 can operate at a relatively high RPM (maximum RPM) set based on the heat load (i.e., the high load of the HVAC subsystem 11).

[0165] The controller can be configured to determine whether the heat load HL exceeds the second reference load HL2 and whether the heat generated Q from the power system components 51 and 52 is greater than or equal to the heat capacity W generated by the heating operation of the HVAC subsystem 11. hp (S29). When the heat load HL exceeds the second reference load HL2 and the heat output Q is greater than or equal to the heat capacity W. hp At that time, the controller 100 can be configured to determine that the heating operation conditions of the HVAC subsystem 11 meet the high load conditions and that the heat output Q of the power system components 51 and 52 is sufficient to evaporate the refrigerant circulating in the HVAC subsystem 11.

[0166] When the heat load HL exceeds the second reference load HL2 and the heat output Q is greater than or equal to the heat capacity W hpAt this time, the controller 100 can be configured to switch the third three-way valve 63 to open the inlet of the powertrain bypass pipe 55. When the inlet of the powertrain bypass pipe 55 is opened by switching the third three-way valve 63, the powertrain coolant can pass through the powertrain bypass pipe 55 and bypass the powertrain radiator 53, so the powertrain coolant can absorb heat from the ambient air without passing through the powertrain radiator 53. In other words, when the inlet of the powertrain bypass pipe 55 is opened by switching the third three-way valve 63, the flow of powertrain coolant into the powertrain radiator 53 can be prevented (S30), and the powertrain coolant can pass through powertrain components 51 and 52.

[0167] The controller 100 can be configured to stop the first battery-side pump 44 and start the powertrain-side pump 54 (S31), such that the refrigerant circulating in the HVAC subsystem 11 can pass only through powertrain components 51 and 52, and therefore, the powertrain coolant can absorb heat only from powertrain components 51 and 52, and the refrigerant circulating in the HVAC subsystem 11 can exchange heat only with the powertrain coolant that has absorbed heat from powertrain components 51 and 52. The powertrain coolant can circulate through powertrain components 51 and 52 and the first passage 71 of the water-cooled heat exchanger 70, and the refrigerant circulating in the HVAC subsystem 11 can be heated and evaporated only by the powertrain coolant that has absorbed heat from powertrain components 51 and 52. Here, the powertrain-side pump 54 can operate at a relatively high RPM (maximum RPM) set based on the heat load (i.e., the high load of the HVAC subsystem 11).

[0168] When the heating operating conditions of the HVAC subsystem 11 meet the low load conditions, the first battery-side pump 44 can operate at a relatively low first RPM based on the low load conditions. When the heating operating conditions of the HVAC subsystem 11 meet the medium load conditions, it can operate at a medium second RPM based on the medium load conditions. When the heating operating conditions of the HVAC subsystem 11 meet the high load conditions, it can operate at a relatively high third RPM based on the high load conditions. The second RPM can be greater than the first RPM, and the third RPM can be greater than the second RPM. In other words, the RPM of the first battery-side pump 44 can increase proportionally to the heat load.

[0169] When the heating operating conditions of HVAC subsystem 11 meet low load conditions, the power system side pump 54 may not operate. When the heating operating conditions of HVAC subsystem 11 meet medium load conditions, the power system side pump 54 may be set to a medium fourth RPM operation based on medium load conditions. And when the heating operating conditions of HVAC subsystem 11 meet high load conditions, the power system side pump 54 may be set to a relatively high fifth RPM operation based on high load conditions. The fifth RPM may be greater than the fourth RPM. In other words, the RPM of the power system side pump 54 can be increased proportionally to the heat load.

[0170] According to an exemplary embodiment, the heat load HL can be defined as the pressure of the refrigerant discharged from the outlet of the compressor 32, i.e., the discharge pressure P of the compressor 32. The first reference load HL1 can be defined as the first reference pressure P1, and the second reference load HL2 can be defined as the second reference pressure P2. When the discharge pressure P of the compressor 32 is less than or equal to the first reference pressure P1, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet low-load conditions. When the discharge pressure P of the compressor 32 exceeds the first reference pressure P1 and is less than or equal to the second reference pressure P2, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet medium-load conditions. When the discharge pressure P of the compressor 32 exceeds the second reference pressure P2, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet high-load conditions.

[0171] According to another exemplary embodiment, the heat load HL can be defined by the RPM of the compressor 32. A first reference load HL1 can be defined as a first RPM RPM1, and a second reference load HL2 can be defined as a second RPM RPM2. When the RPM of the compressor 32 is less than or equal to the first RPM RPM1, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet low load conditions. When the RPM of the compressor 32 exceeds the first RPM RPM1 and is less than or equal to the second RPM RPM2, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet medium load conditions. When the RPM of the compressor 32 exceeds the second RPM RPM2, the controller 100 can be configured to determine that the heating operating conditions of the HVAC subsystem 11 meet high load conditions.

[0172] As described above, during the heating operation of the HVAC subsystem according to an exemplary embodiment of the present invention, the vehicle thermal management system allows the refrigerant circulating in the HVAC subsystem to selectively recover heat from the ambient air and / or waste heat from electrical / electronic components based on driving conditions, vehicle charging conditions, and the heating operation conditions of the HVAC subsystem, thereby achieving refrigerant evaporation performance and thus meeting the required heating performance of the HVAC subsystem.

[0173] According to an exemplary embodiment of the present invention, when the heat generation of the power system components (motor, electrical / electronic components, etc.) is relatively high, the refrigerant circulating in the HVAC subsystem can absorb heat from the power system components, thereby satisfying the required heating performance of the HVAC subsystem. When the heat generation of the power system components is relatively low, the refrigerant circulating in the HVAC subsystem can absorb heat from the power system components and the ambient air, thereby satisfying the required heating performance of the HVAC subsystem.

[0174] According to an exemplary embodiment of the present invention, when the heat load required for the heating operation of the HVAC subsystem is medium or high, the refrigerant circulating in the HVAC subsystem can absorb heat from the power system components and / or ambient air, thereby satisfying the required heating performance of the HVAC subsystem. When the heat load required for the heating operation of the HVAC subsystem is low, the refrigerant circulating in the HVAC subsystem can absorb heat from the ambient air, thereby satisfying the required heating performance of the HVAC subsystem.

[0175] While the present invention has been described above with reference to exemplary embodiments and accompanying drawings, the present invention is not limited thereto. Various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the invention as claimed in the appended claims.

Claims

1. A method for controlling the heating of a vehicle thermal management system, the vehicle thermal management system including a heating, ventilation, and air conditioning (HVAC) subsystem, the method comprising the following steps: In response to determining that the passenger compartment needs to be heated, the controller starts the compressor of the HVAC subsystem; The controller determines whether the heat generated from the power system components is greater than or equal to the reference heat generated. In response to determining that the heat generation is greater than or equal to the reference heat generation, the controller starts the powertrain-side pump and stops the battery-side pump, wherein the refrigerant circulating in the HVAC subsystem exchanges heat with the powertrain coolant that has absorbed heat from the powertrain components; and In response to determining that the heat generation is less than the reference heat generation, the controller starts the powertrain-side pump and the battery-side pump, wherein the refrigerant circulating in the HVAC subsystem exchanges heat with the powertrain coolant that has absorbed heat from the powertrain components, and simultaneously exchanges heat with the battery coolant that has absorbed heat from the ambient air. The method further includes the following steps: The controller monitors the temperature of the powertrain coolant that has absorbed heat from the powertrain components and the temperature of the battery coolant that has absorbed heat from the ambient air. The controller calculates the temperature difference between the powertrain coolant and the battery coolant; and The controller determines whether the temperature difference value is greater than or equal to the reference value. The controller is configured to determine that the calorific value is greater than or equal to the reference calorific value in response to determining that the temperature difference value is greater than or equal to the reference calorific value, and The controller is configured to determine that the calorific value is less than the reference calorific value in response to determining that the temperature difference value is less than the reference calorific value.

2. The method according to claim 1, wherein, The battery-side pump is configured to pass the battery coolant through a battery radiator, the battery radiator being configured to contact ambient air, and the powertrain-side pump is configured to pass the powertrain coolant through the powertrain components.

3. The method according to claim 1, wherein, The temperature of the powertrain coolant is measured by a first coolant temperature sensor located downstream of the powertrain component along the flow direction of the powertrain coolant, and the temperature of the battery coolant is measured by a second coolant temperature sensor located downstream of the battery radiator along the flow direction of the battery coolant.

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