Heat pump system for vehicle

Abstract

A heat pump system for a vehicle includes: an air conditioning unit including a compressor, a second heat exchanger, a third heat exchanger, and a fourth heat exchanger connected by a refrigerant line to circulate refrigerant through the refrigerant line; and a cooler connected to the refrigerant line through a second connection line and configured to perform heat exchange between the refrigerant supplied from the air conditioning unit and the coolant to adjust a temperature of the coolant, in which the air conditioning unit further includes: a first control device provided in the refrigerant line downstream of the compressor; the first heat exchanger is connected to the first control device through a first connecting pipeline; a second control device provided upstream of the cooler and the fourth heat exchanger at a position where the refrigerant line is connected to the second connection line; a third control device provided in the refrigerant line between the fourth heat exchanger and the compressor; the third connecting pipeline comprises a first end and a second end; and a fourth control device.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0113273, filed on August 29, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a heat pump system for a vehicle, and more particularly to a heat pump system for a vehicle capable of performing cooling or heating of the interior of the vehicle. Background Art

[0004] Generally, an air conditioning system for a vehicle includes an air conditioning unit that circulates a refrigerant to heat or cool the interior of the vehicle.

[0005] The air conditioning unit is used to keep the interior of the vehicle at an appropriate temperature regardless of changes in the outside temperature. The air conditioning unit is configured to heat or cool the interior of the vehicle. This is achieved by using the condenser and evaporator to perform heat exchange in the process of the refrigerant discharged by the driving compressor circulating through the condenser, receiving dryer, expansion valve and evaporator and returning to the compressor again.

[0006] In other words, the air conditioning unit lowers the temperature and humidity inside the vehicle in cooling mode by condensing the high-temperature and high-pressure gas-phase refrigerant compressed by the compressor by the condenser, passing the refrigerant through the receiving dryer and the expansion valve, and then evaporating the refrigerant in the evaporator.

[0007] The development of environmentally friendly technologies for vehicles is likely to be the core technology for the future of the automotive industry. Advanced automobile manufacturers focus their energy on the development of environmentally friendly vehicles to comply with regulations related to the environment and fuel efficiency.

[0008] Recently, based on the increasing interest in energy efficiency and environmental pollution issues, there is a need to develop environmentally friendly vehicles that can substantially replace internal combustion engine vehicles. Environmentally friendly vehicles are divided into electric vehicles driven by using fuel cells or electricity as a power source, and hybrid vehicles driven by using an engine and a battery.

[0009] Currently, electric vehicles are attracting attention as a future means of transportation for solving environmental problems and energy resource problems.

[0010] A heat pump system, as an air conditioning device for adjusting the temperature inside the vehicle, is applied to such an electric vehicle.

[0011] However, refrigerants commonly used in heat pump systems contain a large amount of environmentally regulated materials, such as PFAS (per- and polyfluoroalkyl substances).

[0012] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention. Therefore, this Background section may contain information that does not form the prior art that is already known to a person skilled in the art. Summary of the invention

[0013] The present invention provides a heat pump system for a vehicle that can perform cooling or heating of the interior of a vehicle by using a natural refrigerant. In addition, the present invention provides a heat pump system for a vehicle that can effectively adjust the temperature of a battery module by using a single cooler that can perform heat exchange between a refrigerant and a coolant to comply with environmental regulations.

[0014] In addition, the heat pump system can maximize cooling and heating performance by operating in a supercritical cycle (a state in which the pressure and temperature of the refrigerant are above a threshold pressure and temperature) by applying R744 refrigerant, which is a natural refrigerant using carbon dioxide.

[0015] In one embodiment of the present invention, a heat pump system for a vehicle includes: an air conditioning unit including a compressor, a second heat exchanger, a third heat exchanger, and a fourth heat exchanger connected by a refrigerant line so that the refrigerant circulates through the refrigerant line. The heat pump system also includes a cooler connected to the refrigerant line through a second connecting line and configured to perform heat exchange between the refrigerant supplied from the air conditioning unit and the coolant to adjust the temperature of the coolant. The air conditioning unit also includes: a first control device arranged in the refrigerant line downstream of the compressor; a first heat exchanger connected to the first control device through a first connecting line. The air conditioning unit also includes: a second control device arranged upstream of the cooler and the fourth heat exchanger at a position where the refrigerant line is connected to the second connecting line; a third control device arranged in the refrigerant line between the fourth heat exchanger and the compressor; the third connecting line includes: a first end connected to the refrigerant line between the fourth heat exchanger and the third control device; and a second end connected to the refrigerant line between the third heat exchanger and the second control device. The air conditioning unit also includes: a fourth control device arranged in the third connecting line.

[0016] The first control device includes: a first valve provided in a refrigerant line between the compressor and the second heat exchanger; and a second valve provided in a first connecting line between the compressor and the first heat exchanger.

[0017] The first valve and the second valve are two-way valves.

[0018] The first control device includes: a single control valve provided at a portion where the refrigerant line and the first connecting line are connected.

[0019] The second control device includes a first expansion valve disposed in the refrigerant line upstream of the fourth heat exchanger. The second control device also includes a second expansion valve disposed in the second connecting line upstream of the cooler.

[0020] The air conditioning unit further includes: a branch line including: a first end connected to the refrigerant line between the first control device and the second heat exchanger; and a second end connected to the third connecting line. The air conditioning unit further includes: a fifth control device disposed in the branch line; and a fourth connecting line including: a first end connected to the refrigerant line between the second heat exchanger and the third heat exchanger; and a second end connected to the refrigerant line between the third control device and the compressor. The air conditioning unit further includes: a sixth control device disposed in the fourth connecting line; and a seventh control device disposed in the first connecting line.

[0021] The third control device and the sixth control device are two-way valves.

[0022] The fourth control device, the fifth control device and the seventh control device are expansion valves.

[0023] In the cooling mode of the vehicle interior, the refrigerant line connecting the fourth heat exchanger and the compressor is opened by the operation of the third control device. The refrigerant line connecting the compressor and the second heat exchanger is opened by the operation of the first control device. The first connecting line is closed by the operation of the first control device and the seventh control device. The third connecting line is closed by the operation of the fourth control device. The branch line is closed by the operation of the fifth control device. And the fourth connecting line is closed by the operation of the sixth control device.

[0024] In the cooling mode inside the vehicle, when cooling of the battery module is required, the second connecting line is opened by the operation of the second control device.

[0025] The second control device is configured to expand the refrigerant introduced into the second connecting line and flow the expanded refrigerant to the cooler, thereby cooling the battery module by exchanging heat with the refrigerant in the cooler using the coolant.

[0026] In the heating mode of the vehicle interior, the refrigerant line connecting the third heat exchanger and the fourth heat exchanger is closed by the operation of the second control device. A portion of the refrigerant line connecting the compressor and the third control device is closed by the operation of the third control device. A portion of the refrigerant line connecting the first control device and the second heat exchanger is closed by the operation of the first control device. The first connecting line is opened by the operation of the first control device. The first connecting line is connected to the refrigerant line upstream of the fourth heat exchanger by the operation of the seventh control device. The second connecting line is closed by the operation of the second control device. The third connecting line is opened by the operation of the fourth control device. The branch line is opened by the operation of the fifth control device. And the fourth connecting line is opened by the operation of the sixth control device.

[0027] In another embodiment, the fourth control device is configured to expand the refrigerant so that the expanded refrigerant is supplied to the third heat exchanger. The fifth control device is configured to expand the refrigerant so that the expanded refrigerant is supplied to the second heat exchanger.

[0028] A portion of the refrigerant introduced from the fourth heat exchanger into the third connecting line is introduced into the second heat exchanger through the branch line, and the rest of the refrigerant is introduced into the third heat exchanger.

[0029] The refrigerant discharged from the second heat exchanger and the third heat exchanger is supplied to the compressor along a fourth connecting line.

[0030] The seventh control device is configured to supply the refrigerant introduced through the first connecting line to the fourth heat exchanger in an unexpanded state.

[0031] In a heating mode of the vehicle interior, when dehumidification is required, the seventh control device is configured to expand the refrigerant introduced through the first connecting line and supply the expanded refrigerant to the fourth heat exchanger.

[0032] The second heat exchanger, the third heat exchanger, and the fourth heat exchanger are configured to cool or evaporate the refrigerant according to respective selective operations of the second control device, the fourth control device, the fifth control device, and the seventh control device.

[0033] The refrigerant is R744 refrigerant formed from carbon dioxide.

[0034] An accumulator is provided in the refrigerant line between the fourth heat exchanger and the compressor.

[0035] The second heat exchanger is connected to the electric component through a first pipeline through which a coolant circulates; and the cooler is connected to the battery module through a second pipeline through which a coolant circulates.

[0036] The first heat exchanger, the third heat exchanger, and the fourth heat exchanger are air-cooled gas coolers configured to perform heat exchange between refrigerant and air. The second heat exchanger and the cooler are water-cooled gas coolers configured to perform heat exchange between refrigerant and coolant.

[0037] As described above, by adopting the heat pump system for a vehicle according to the embodiment, when cooling or heating of the vehicle interior is performed by using a natural refrigerant, it is possible to cope with the requirements of environmental regulations and improve the overall marketability of the vehicle.

[0038] In addition, according to the present invention, by applying R744 refrigerant as a natural refrigerant using carbon dioxide, cooling and heating performance can be maximized by operating in a supercritical region, which is a state where the pressure and temperature of the refrigerant are higher than the threshold pressure and temperature, for cooling and heating the interior of the vehicle.

[0039] Furthermore, according to the present invention, the temperature of the battery module can be effectively adjusted by using a single cooler that heat-exchanges a coolant and a refrigerant based on a mode of a vehicle, thereby achieving streamlining and simplification of the system.

[0040] Furthermore, according to the embodiments, by effectively regulating the temperature of the battery module, optimal performance of the battery module may be achieved, and the overall driving distance of the vehicle can be increased due to efficient management of the battery module.

[0041] In addition, in the heating mode of the vehicle interior, according to the present invention, since the refrigerant is branched and expanded and supplied to each heat exchanger, it is easy to control the flow of the refrigerant, smoothly recover the ambient air heat and the waste heat of the electrical components, and at the same time, the cooler for cooling the battery module can be optimally designed.

[0042] Furthermore, according to the embodiments, manufacturing cost and weight can be reduced, and space utilization can be improved by simplifying the entire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] These drawings are only used to describe the embodiments of the present invention. Therefore, the technical idea of ​​the present invention is not limited to the drawings, in which:

[0044] Figure 1 is a block diagram of a heat pump system for a vehicle according to an embodiment;

[0045] Figure 2 is a schematic diagram of a first control device for a heat pump system for a vehicle according to an embodiment;

[0046] Figure 3 is a schematic diagram of another embodiment of a first control device for a heat pump system for a vehicle according to an embodiment;

[0047] Figure 4 is a schematic diagram of a second control device for a heat pump system for a vehicle according to an embodiment;

[0048] Figure 5 is an operation diagram of cooling a battery module in a cooling mode for an interior of a vehicle in a heat pump system for a vehicle according to an embodiment; and

[0049] Figure 6 is an operation diagram based on a heating mode of the interior of a vehicle in a heat pump system for a vehicle according to an embodiment.

[0050] <Description of Reference Numerals>

[0051] 2, 4: First pipeline and second pipeline

[0052] 3: Electrical components

[0053] 5: Battery module

[0054] 11: Refrigerant pipeline

[0055] 12: HVAC module

[0056] 13, 14, 15, 17: first, second, third and fourth heat exchangers

[0057] 18: Compressor

[0058] 19: Liquid reservoir

[0059] 21: First connecting pipeline

[0060] 30: Cooler

[0061] 31: Second connecting pipeline

[0062] 42: First control device

[0063] 44: Second control device

[0064] 46: Third control device

[0065] 51: Third connecting pipeline

[0066] 52: Fourth control device

[0067] 53: Branch pipeline

[0068] 54: Fifth control device

[0069] 61: Fourth connecting pipeline

[0070] 62: Sixth control device

[0071] 72: Seventh control device. DETAILED DESCRIPTION

[0072] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0073] The embodiments disclosed in the present invention and the configurations depicted in the accompanying drawings are only some embodiments of the present invention and do not cover the entire scope of the present invention. Therefore, it should be understood that various equivalents and modifications may exist when applying the present specification.

[0074] In order to clarify the present invention, parts irrelevant to the description are omitted, and the same elements or equivalents are denoted by the same reference numerals throughout the specification.

[0075] In addition, the size and thickness of each element are arbitrarily shown in the drawings, but the present invention is not limited thereto. In addition, in the drawings, the thickness of layers, films, panels, regions, etc. are exaggerated for clarity.

[0076] In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of other elements.

[0077] In addition, terms such as “unit,” “means,” “portion,” “component,” and “member” described in the specification refer to a unit of a combination of elements that performs at least one function or operation.

[0078] When a component, device, element, etc. of the present invention is described as having a purpose or performing an operation, function, etc., the component, device or element should be considered herein as being "configured to" satisfy the purpose or perform the operation or function.

[0079] Figure 1 A block diagram of a heat pump system for a vehicle according to an embodiment is shown. Figure 2 is a schematic diagram of a first control device of a heat pump system for a vehicle according to an embodiment. Figure 3 is a schematic diagram of another embodiment of a first control device for a heat pump system for a vehicle according to an embodiment. Figure 4 is a schematic diagram of a second control device for a heat pump system for a vehicle according to an embodiment.

[0080] According to an embodiment of the present invention, the heat pump system for a vehicle can perform cooling or heating of the interior of the vehicle by using a natural refrigerant and effectively adjust the temperature of the battery module 5. This is achieved by using a single cooler 30 that exchanges heat between the refrigerant and the coolant to comply with environmental regulations.

[0081] The refrigerant may be R744 refrigerant formed of carbon dioxide, which has an ozone depletion potential (ODP) of 0 and a global warming potential (GWP) of 1.

[0082] In other words, by applying R744 refrigerant which is a natural refrigerant using carbon dioxide, the heat pump system for a vehicle according to the embodiment can maximize cooling and heating performance by operating in a supercritical cycle, which is a state in which the pressure and temperature of the refrigerant are higher than a threshold pressure and temperature.

[0083] To this end, the heat pump system according to the embodiment may include an air conditioning unit and a cooler 30 .

[0084] Reference Figure 1 The air conditioning unit includes a second heat exchanger 14 , a third heat exchanger 15 , a fourth heat exchanger 17 , and a compressor 18 connected by a refrigerant line 11 so that the refrigerant circulates through the refrigerant line 11 .

[0085] The first heat exchanger 13 may be connected to the refrigerant line 11 through a first connection line 21. The first heat exchanger 13 may exchange heat between the refrigerant selectively supplied from the compressor 18 and the air.

[0086] In other words, the first heat exchanger 13 may be disposed in the first connecting line 21 .

[0087] A first end of the first connecting line 21 may be connected to a first control device 42 disposed in the refrigerant line 11 between the compressor 18 and the second heat exchanger 14 .

[0088] A second end of the first connecting line 21 may be connected to the refrigerant line 11 between the second control device 44 and the fourth heat exchanger 17 .

[0089] That is, the first heat exchanger 13 is connected to the first control device 42 via the first connecting line 21 .

[0090] The first control device 42 may be disposed in the refrigerant line 11 downstream of the compressor 18 .

[0091] like Figure 2 As shown, the first control device 42 may include a first valve 42a and a second valve 42b.

[0092] First, the first valve 42 a is provided in the refrigerant line 11 between the compressor 18 and the second heat exchanger 14 .

[0093] In addition, a second valve 42 b may be provided at the first connecting line 21 between the compressor 18 and the first heat exchanger 13 .

[0094] A first end of the first connecting line 21 is connected to the refrigerant line 11 between the compressor 18 and the first valve 42 a .

[0095] The first valve 42 a and the second valve 42 b configured as such may be two-way valves that control opening and closing of the refrigerant line 11 and the first connecting line 21 .

[0096] In other words, the first control device 42 is provided in the refrigerant line 11 between the compressor 18 and the second heat exchanger 14 .

[0097] In the vehicle interior cooling mode, the first control device 42 can cause the refrigerant supplied from the compressor 18 to flow to the second heat exchanger 14 (see Figure 5 ).

[0098] On the other hand, in the vehicle interior heating mode, the first control device 42 can supply the refrigerant introduced through the refrigerant line 11 to the first heat exchanger 13 through the first connecting line 21 (see Figure 6 ).

[0099] In this embodiment, the first control device 42 is equipped with two two-way valves, but is not limited thereto. Figure 3 The first control device 42 according to another embodiment will be described.

[0100] Reference Figure 3 In another embodiment, the first control device 42 may include a control valve 142 disposed at a location where the refrigerant line 11 is connected to the first connecting line 21 .

[0101] The control valve 142 can selectively connect the refrigerant pipeline 11 and the first connecting pipeline 21 , and can control the flow direction and flow rate of the refrigerant.

[0102] That is, the first control device 42 of another embodiment applies the control valve 142 configured with a three-way valve, and can not only reduce the number of valves but also perform the same operation as the above-described embodiment.

[0103] In the present embodiment, the second heat exchanger 14 may be connected to the compressor 18 via the refrigerant line 11. Thus, the refrigerant supplied to the refrigerant line 11 can flow through the second heat exchanger 14.

[0104] The second heat exchanger 14 may be connected to the electric component 3 via a first pipeline 2 through which a coolant circulates.

[0105] The electrical components 3 may include a power conversion device such as an electric power control unit (EPCU), a motor, an inverter, an on-board charger (OBC), and an autonomous driving controller.

[0106] The electric component 3 configured in this way can be water-cooled by being connected to the first pipeline 2 .

[0107] In this embodiment, the third heat exchanger 15 may be connected to the second heat exchanger 14 through the refrigerant line 11. The third heat exchanger 15 is disposed at the front side of the vehicle and may cool or evaporate the refrigerant by exchanging heat with air introduced from the outside when the vehicle is running.

[0108] Since R744 refrigerant is a supercritical refrigerant, unlike typical refrigerants, it does not undergo phase changes and is therefore described as a gas cooling refrigerant rather than a condensing refrigerant.

[0109] In addition, the second heat exchanger 14 may cool or evaporate the refrigerant by exchanging heat with the coolant supplied through the first line 2. The second heat exchanger 14 may be a water-cooled gas cooler that exchanges heat between the refrigerant introduced inside and the coolant.

[0110] In this embodiment, the fourth heat exchanger 17 may be disposed in the refrigerant line 11 between the third heat exchanger 15 and the compressor 18 .

[0111] The first heat exchanger 13 and the fourth heat exchanger 17 may be disposed within an HVAC module (heating, ventilation, and air conditioning module) 12 .

[0112] That is, the first heat exchanger 13 , the third heat exchanger 15 , and the fourth heat exchanger 17 may be air-cooling type gas coolers that exchange heat between the refrigerant introduced into the inside and the air.

[0113] In the present embodiment, an accumulator 19 may be provided in the refrigerant line 11 between the fourth heat exchanger 17 and the compressor 18 .

[0114] The accumulator 19 supplies only gaseous refrigerant to the compressor 18 , thereby improving the efficiency and durability of the compressor 18 .

[0115] Furthermore, although not shown in the drawings, an internal heat exchanger may be provided within the reservoir 19 .

[0116] The internal heat exchanger may heat-exchange the refrigerant cooled in the third heat exchanger 15 with the low-temperature refrigerant discharged from the fourth heat exchanger 17 , and may supply the heat-exchanged refrigerant to the compressor 18 and the fourth heat exchanger 17 , respectively.

[0117] In the present embodiment, the cooler 30 may be connected to the battery module 5 via the second line 4 through which the coolant circulates. Thus, the coolant may selectively circulate through the cooler 30.

[0118] The cooler 30 is connected to the refrigerant line 11 through the second connecting line 31. That is, the cooler 30 may be a water-cooled gas cooler that exchanges heat between the refrigerant introduced inside and the coolant.

[0119] A first end of the second connecting line 31 may be connected to the second control device 44. A second end of the second connecting line 31 may be connected to the refrigerant line 11 between the heat exchanger 17 and the accumulator 19.

[0120] The second control device 44 may be provided at a location upstream of the fourth heat exchanger 17 and the cooler 30 where the refrigerant line 11 and the second connecting line 31 are connected.

[0121] An upstream of the fourth heat exchanger 17 , a downstream of the fourth heat exchanger 17 , an upstream of the cooler 30 , and a downstream of the cooler 30 may be set based on a flow direction of the refrigerant.

[0122] In other words, based on the direction in which the refrigerant flows along the refrigerant line 11 , the position where the refrigerant is introduced into the fourth heat exchanger 17 may be defined as upstream of the fourth heat exchanger 17 , and the position where the refrigerant is discharged from the fourth heat exchanger 17 may be defined as downstream of the fourth heat exchanger 17 .

[0123] In addition, based on the direction in which the refrigerant flows along the second connecting line 31 , a position where the refrigerant is introduced into the cooler 30 may be defined as upstream of the cooler 30 , and a position where the refrigerant is discharged from the cooler 30 may be defined as downstream of the cooler 30 .

[0124] like Figure 4 As shown, the second control device 44 may include a first expansion valve 44a and a second expansion valve 44b.

[0125] First, the first expansion valve 44a is provided in the refrigerant line 11 upstream of the fourth heat exchanger 17. In addition, the second expansion valve 44b is provided in the second connecting line 31 upstream of the cooler 30.

[0126] The second control device 44 thus configured can selectively expand the refrigerant introduced through the refrigerant line 11 .

[0127] In addition, the second control device 44 may supply refrigerant to one or both of the fourth heat exchanger 17 and the cooler 30 through the refrigerant line 11 and the second connecting line 31 .

[0128] In other words, the second control device 44 can selectively expand the refrigerant while controlling the flow of the refrigerant.

[0129] Therefore, the cooler 30 may heat-exchange the coolant selectively introduced through the second line 4 with the refrigerant selectively supplied from the air-conditioning unit. Therefore, the cooler 30 may adjust the temperature of the coolant.

[0130] The coolant having undergone heat exchange in the cooler 30 may circulate through the battery module 5 via the second line 4 .

[0131] Water pumps (not shown) may be provided in the first pipeline 2 and the second pipeline 4 .

[0132] That is, the coolant may circulate in the first line 2 and the second line 4 according to the operation of each water pump (not shown).

[0133] Thus, the coolant that has exchanged heat with the refrigerant in the second heat exchanger 14 and the cooler 30 can be selectively supplied to the electric components 3 and the battery modules 5 to adjust the temperatures of the electric components 3 and the battery modules 5 .

[0134] The second control device 44 may selectively expand the refrigerant according to a cooling mode or a heating mode of the vehicle interior, and make the expanded refrigerant flow to the cooler 30 via the second connecting line 31 .

[0135] In addition, the second control device 44 may supply the introduced refrigerant to the cooler 30 through the second connecting line 31 without expansion, or close the second connecting line 31 so that the refrigerant is not supplied to the cooler 30 .

[0136] In more detail, when the battery module 5 is cooled by the coolant heat-exchanged with the refrigerant in the cooler 30, the second control device 44 may open the second connection line 31. At the same time, the second control device 44 expands the introduced refrigerant. The expanded refrigerant may flow to the cooler 30 through the second connection line 31.

[0137] That is, the second control device 44 may expand the refrigerant discharged from the third heat exchanger 15 to lower its temperature and flow the expanded refrigerant to the cooler 30 , thereby further lowering the temperature of the coolant flowing through the inside of the cooler 30 .

[0138] Thus, by cooling the coolant while flowing through the cooler 30 , the battery module 5 can be cooled more efficiently.

[0139] In this embodiment, the air conditioning unit may further include a third control device 46 , a third connecting line 51 , a fourth control device 52 , a branch line 53 , a fifth control device 54 , a fourth connecting line 61 , a sixth control device 62 and a seventh control device 72 .

[0140] First, the third control device 46 may be disposed in the refrigerant line 11 between the fourth heat exchanger 17 and the compressor 18 .

[0141] In this embodiment, a first end of the third connecting line 51 is connected to the refrigerant line 11 between the fourth heat exchanger 17 and the third control device 46. A second end of the third connecting line 51 is connected to the refrigerant line 11 between the third heat exchanger 15 and the second control device 44.

[0142] Furthermore, a fourth control device 52 may be arranged in the third connecting line 51 .

[0143] In vehicle interior heating mode, refer to Figure 6 The fourth control device 52 may expand the refrigerant introduced through the third connecting line 51 and supply the expanded refrigerant to the third heat exchanger 15 .

[0144] That is, the third heat exchanger 15 may cool or evaporate the introduced refrigerant according to the selective operation of the fourth control device 52 .

[0145] In the present embodiment, a first end of the branch line 53 is connected to the refrigerant line 11 between the first control device 42 and the second heat exchanger 14. In addition, a second end of the branch line 53 may be connected to the third connection line 51.

[0146] The fifth control device 54 is provided in the branch line 53. The fifth control device 54 may operate so that some of the refrigerant introduced into the third connecting line 51 may be introduced into the second heat exchanger 14.

[0147] In addition, the fifth control device 54 may prevent the refrigerant flowing along the refrigerant line 11 from flowing back to the third connecting line 51 through the branch line 53 .

[0148] That is, the branch line 53 may be opened by the operation of the fifth control device 54 so that some of the refrigerant introduced into the third connecting line 51 may be supplied to the second heat exchanger 14 .

[0149] Thus, some of the refrigerant introduced into the third connecting line 51 is introduced into the second heat exchanger 14 through the branch line 53 , and the rest of the refrigerant may be introduced into the third heat exchanger 15 .

[0150] In vehicle interior heating mode, refer to Figure 6 , the fifth control device 54 may expand the refrigerant introduced through the branch line 53 and supply the expanded refrigerant to the second heat exchanger 14 .

[0151] Therefore, in the vehicle interior heating mode, referring to Figure 6 , the second heat exchanger 14 may evaporate the refrigerant by exchanging heat with the coolant supplied through the first line 2. That is, according to the selective operation of the fifth control device 54, the second heat exchanger 14 may cool or evaporate the introduced refrigerant by exchanging heat with the coolant supplied through the first line 2.

[0152] In this embodiment, a first end of the fourth connecting line 61 is connected to the refrigerant line 11 between the second heat exchanger 14 and the third heat exchanger 15. In addition, a second end of the fourth connecting line 61 may be connected to the refrigerant line 11 between the third control device 46 and the compressor 18.

[0153] The sixth control device 62 may be disposed in the fourth connecting line 61. The sixth control device 62 may selectively open and close the fourth connecting line 61.

[0154] More specifically, in the cooling mode of the vehicle interior, refer to Figure 5 , the sixth control device 62 can close the fourth connecting line 61. On the contrary, in the heating mode of the vehicle interior, refer to Figure 6 , the sixth control device 62 can open the fourth connecting pipeline 61.

[0155] That is, the fourth connecting line 61 may selectively introduce the refrigerant discharged from the second heat exchanger 14 and the third heat exchanger 15 directly into the accumulator 19 through the operation of the sixth control device 62 .

[0156] In addition, the seventh control device 72 may be provided in the first connecting line 21. In the cooling mode of the vehicle interior, referring to Figure 5 , the seventh control device 72 can operate together with the first control device 42 to close the first connecting pipeline 21.

[0157] On the other hand, in the vehicle interior heating mode, if Figure 6 As shown, the seventh control device 72 may operate together with the first control device 42 to open the first connecting line 21. At this time, the seventh control device 72 may supply the refrigerant introduced through the first connecting line 21 to the fourth heat exchanger 17 in an unexpanded state.

[0158] Reference Figure 6 When dehumidification is required in the heating mode of the vehicle interior, the seventh control device 72 may expand the refrigerant introduced through the first connecting line 21 and supply the expanded refrigerant to the fourth heat exchanger 17 .

[0159] The third control device 46 and the sixth control device 62 may be two-way valves.

[0160] In addition, the fourth control device 52, the fifth control device 54, and the seventh control device 72 may be expansion valves.

[0161] In the heat pump system thus configured, the second heat exchanger 14 can cool or evaporate the introduced refrigerant according to the selective operation of the fifth control device 54 .

[0162] The third heat exchanger 15 may cool or evaporate the introduced refrigerant according to the selective operation of the fourth control device 52 .

[0163] In addition, the fourth heat exchanger 17 may cool or evaporate the introduced refrigerant according to the selective operation of the second control device 44 or the seventh control device 72 .

[0164] In other words, the second heat exchanger 14 , the third heat exchanger 15 , and the fourth heat exchanger 17 may evaporate the refrigerant when the expanded refrigerant is introduced, and cool the refrigerant when the unexpanded refrigerant is introduced.

[0165] In the following, reference Figure 5 and Figure 6 The operation and effect of the heat pump system for a vehicle according to the embodiment configured as described above will be described in detail.

[0166] First, in the cooling mode inside the vehicle, refer to Figure 5 The operation for cooling the battery module 5 is described.

[0167] Figure 5 is an operation diagram for cooling a battery module in a cooling mode of a vehicle interior in a heat pump system of a vehicle according to one embodiment.

[0168] refer to Figure 5 , the coolant may circulate through the first pipeline 2 by operation of a water pump (not shown).

[0169] Thereby, the coolant having passed through the electric component 3 may be supplied to the second heat exchanger 14 along the first pipeline 2 .

[0170] Each component in the air conditioning unit operates for cooling the interior of the vehicle. Thus, refrigerant circulates along the refrigerant line 11 .

[0171] The refrigerant line 11 connecting the fourth heat exchanger 17 and the compressor 18 is opened by the operation of the third control device 46 .

[0172] The refrigerant line 11 connecting the compressor 18 and the second heat exchanger 14 is opened by the operation of the first control device 42 .

[0173] At the same time, the first connecting line 21 is closed by the operations of the first control device 42 and the seventh control device 72 .

[0174] In addition, the third connecting line 51 is closed by the operation of the fourth control device 52. The branch line 53 is closed by the operation of the fifth control device 54.

[0175] Furthermore, the fourth connecting line 61 is closed by the operation of the sixth control device 62 .

[0176] The second connecting line 31 is opened by the operation of the second control device 44 to cool the battery module 5 .

[0177] At this time, the coolant may be circulated through the second line 4 by the operation of a water pump (not shown). Thus, the coolant having passed through the battery module 5 may be supplied to the cooler 30 along the second line 4.

[0178] The second control device 44 may expand the refrigerant for cooling the battery module 5 by using the coolant heat-exchanged with the refrigerant in the cooler 30 and flow the expanded refrigerant to the second connection line 31. The expanded refrigerant may be introduced into the cooler 30 along the second connection line 31.

[0179] Therefore, the coolant having passed through the cooler 30 may be cooled by heat-exchanging with the expanded refrigerant supplied to the cooler 30 .

[0180] That is, the coolant flowing through the cooler 30 is cooled due to heat exchange with the expanded refrigerant supplied to the cooler 30. The coolant cooled in the cooler 30 is supplied to the battery module 5 along the second line 4. Thus, the battery module 5 can be efficiently cooled using the coolant cooled in the cooler 30.

[0181] The refrigerant supplied from the compressor 18 may sequentially flow through the second heat exchanger 14 and the third heat exchanger 15 along the refrigerant line 11 .

[0182] The second heat exchanger 14 may primary cool the refrigerant using the coolant flowing along the first line 2. Also, the third heat exchanger 15 may secondary cool the refrigerant introduced from the second heat exchanger 14 through heat exchange with air.

[0183] The refrigerant sequentially flowing through the second heat exchanger 14 and the third heat exchanger 15 may circulate along the refrigerant line 11 and the second connecting line 31 opened by the second control device 44 .

[0184] The second control device 44 may expand the refrigerant so that the expanded refrigerant is supplied to the fourth heat exchanger 17 and the cooler 30 .

[0185] That is, the second control device 44 expands the refrigerant introduced into the second connecting line 31 among the refrigerant having passed through the third heat exchanger 15 so that the expanded refrigerant can be supplied to the cooler 30 .

[0186] Therefore, the refrigerant introduced into the second connecting line 31 is expanded by the operation of the second control device 44 to be in a low-temperature and low-pressure state, and is introduced into the cooler 30 provided in the second connecting line 31 .

[0187] Then, the refrigerant introduced into the cooler 30 exchanges heat with the refrigerant supplied through the second line 4 , flows through the accumulator 19 through the refrigerant line 11 connected to the second connecting line 31 , and then is introduced into the compressor 18 .

[0188] The remaining refrigerant discharged from the third heat exchanger 15 flows through the refrigerant line 11 to cool the vehicle interior. The remaining refrigerant flows through the fourth heat exchanger 17, the accumulator 19, and the compressor 18 in sequence.

[0189] The air introduced into the HVAC module 12 is cooled by the refrigerant in a low temperature state introduced into the fourth heat exchanger 17 while passing through the fourth heat exchanger 17 .

[0190] The cooled air can cool the vehicle interior by passing through the first heat exchanger 13 , to which the refrigerant is not supplied, and being directly introduced into the vehicle interior.

[0191] The refrigerant, whose cooling level is increased while sequentially passing through the second heat exchanger 14 and the third heat exchanger 15, is expanded and supplied to the fourth heat exchanger 17. Therefore, the refrigerant may be evaporated at a low temperature.

[0192] That is, in this embodiment, the second heat exchanger 14 cools the refrigerant by heat exchange with the coolant, and the third heat exchanger 15 cools the refrigerant by heat exchange with the air. Therefore, the R744 refrigerant formed by carbon dioxide can be cooled more effectively, which is conducive to the supercooling formation of the refrigerant.

[0193] In addition, since the supercooled refrigerant evaporates at a lower temperature in the fourth heat exchanger 17, the temperature of the air passing through the fourth heat exchanger 17 can be further reduced, thereby improving the cooling performance and efficiency.

[0194] While the above-described process is repeatedly performed, the refrigerant may cool the vehicle interior in the vehicle interior cooling mode while the coolant is cooled by heat exchange while flowing through the cooler 30 .

[0195] The low-temperature coolant cooled at the cooler 30 flows to the battery module 5 via the second line 4. Thus, the battery module 5 can be effectively cooled by the supplied low-temperature coolant.

[0196] In this embodiment, refer to Figure 6 Describes the operation in the heating mode of the vehicle interior.

[0197] Figure 6 is an operation diagram of a heat pump system for a vehicle based on a heating mode of a vehicle interior according to one embodiment.

[0198] refer to Figure 6, the coolant may circulate through the first pipeline 2 by operation of a water pump (not shown).

[0199] Thereby, the coolant having passed through the electric component 3 may be supplied to the second heat exchanger 14 along the first pipeline 2 .

[0200] The various components in the air conditioning unit operate to heat the interior of the vehicle. Thus, the refrigerant circulates along the refrigerant line 11.

[0201] The refrigerant line 11 connecting the third heat exchanger 15 and the fourth heat exchanger 17 is closed by the operation of the second control device 44 .

[0202] At the same time, the second connecting line 31 can be closed by the operation of the second control device 44 .

[0203] A portion of the refrigerant line 11 connecting the compressor 18 and the third control device 46 is closed by the operation of the third control device 46 .

[0204] Furthermore, a portion of the refrigerant line 11 connecting the first control device 42 and the second heat exchanger 14 may be closed by the operation of the first control device 42 .

[0205] At the same time, the first connecting line 21 is opened by the operation of the first control device 42 .

[0206] The first connecting line 21 may be connected to the refrigerant line 11 upstream of the fourth heat exchanger 17 by operation of the seventh control device 72 .

[0207] The seventh control device 72 may supply the refrigerant introduced through the first connecting line 21 after passing through the first heat exchanger 13 to the fourth heat exchanger 17 in an unexpanded state.

[0208] Thus, the fourth heat exchanger 17 may cool the refrigerant by using the air introduced into the HVAC module 12 .

[0209] The third connecting line 51 is opened by the operation of the fourth control device 52. The branch line 53 can be opened by the operation of the fifth control device 54.

[0210] At the same time, a portion of the refrigerant line 11 connecting the branch line 53 and the second heat exchanger 14 may be opened.

[0211] Thereby, the refrigerant having passed through the fourth heat exchanger 17 is introduced into the opened third connecting line 51 .

[0212] Some of the refrigerant introduced into the third connecting line 51 flows to the second heat exchanger 14 via the opened branch line 53 .

[0213] Furthermore, the remaining refrigerant of the refrigerant introduced into the third connecting line 51 is introduced into the third heat exchanger 15 through the third connecting line 51 and the opened refrigerant line 11 , respectively.

[0214] The fourth control device 52 may expand the refrigerant so that the expanded refrigerant may be supplied to the third heat exchanger 15. In addition, the fifth control device 54 may expand the refrigerant so that the expanded refrigerant may be supplied to the second heat exchanger 14.

[0215] Thus, the second heat exchanger 14 can evaporate the expanded refrigerant by exchanging heat with the coolant supplied through the first pipeline 2. At this time, the second heat exchanger 14 can recover the waste heat of the electric component 2. This is achieved by collecting the waste heat generated by the electric component 3 from the heated coolant.

[0216] In addition, the third heat exchanger 15 may recover ambient air heat while evaporating the expanded refrigerant through heat exchange with the air.

[0217] In the present embodiment, the fourth connecting line 61 is opened by the operation of the sixth control device 62 .

[0218] Thus, the refrigerant discharged from the second heat exchanger 14 and the third heat exchanger 15 may be supplied to the compressor 18 along the opened fourth connecting line 61 .

[0219] In this state, the refrigerant supplied from the compressor 18 is introduced into the first heat exchanger 13 along the first connecting line 21 connected to the refrigerant line 11. The refrigerant having passed through the first heat exchanger 13 is introduced into the fourth heat exchanger 17 along the refrigerant line 11 connected to the first connecting line 21.

[0220] The first heat exchanger 13 and the fourth heat exchanger 17 may cool the refrigerant by exchanging heat between the air introduced into the HVAC module 12 and the refrigerant. The refrigerant once cooled in the first heat exchanger 13 may be further cooled in the fourth heat exchanger 17.

[0221] That is, when the refrigerant having passed through the first heat exchanger 13 is supplied to the fourth heat exchanger 17 in an unexpanded state by operation of the seventh control device 72, the fourth heat exchanger 17 can cool the refrigerant by exchanging heat between the air introduced into the HVAC module 12 and the refrigerant.

[0222] The refrigerant having passed through the fourth heat exchanger 17 flows along the opened third connecting line 51. Some of the refrigerant introduced into the third connecting line 51 flows to the fifth control device 54 via the opened branch line 53.

[0223] Furthermore, the remaining refrigerant of the refrigerant introduced into the third connecting line 51 may be introduced into the fourth control device 52 along the third connecting line 51 .

[0224] The fourth control device 52 may expand the refrigerant and supply the expanded refrigerant to the third heat exchanger 15. In addition, the fifth control device 54 may expand the refrigerant and supply the expanded refrigerant to the second heat exchanger 14.

[0225] That is, the refrigerant introduced into the third connecting line 51 is branched via the branch line 53 and is supplied to the second heat exchanger 14 and the third heat exchanger 15 , respectively.

[0226] Thus, the second heat exchanger 14 can cool the supplied refrigerant by exchanging heat with the coolant, while the third heat exchanger 15 can cool the supplied refrigerant by exchanging heat with the air. When such operations are repeatedly performed, the second heat exchanger 14 and the third heat exchanger 15 can recover waste heat of the electrical component 3 and heat from the ambient air.

[0227] That is, since the recovered waste heat of the electric components 3 and the ambient air heat can be used to increase the temperature of the refrigerant, the heat pump system can reduce the power consumption of the compressor 18 and improve the heating efficiency.

[0228] The refrigerant discharged from the second heat exchanger 14 and the third heat exchanger 15 is supplied to the accumulator 19 along the opened fourth connecting line 61 .

[0229] The refrigerant having passed through the accumulator 19 may be supplied to the compressor 18 .

[0230] In addition, the refrigerant compressed to a high-temperature and high-pressure state by the compressor 18 is introduced into the first heat exchanger 13 along the first connecting line 21 .

[0231] As described above, the refrigerant supplied to the first heat exchanger 13 and the fourth heat exchanger 17 may increase the temperature of the air introduced into the HVAC module 12 .

[0232] Thus, the air introduced from the outside can be converted into a high-temperature state while passing through the fourth heat exchanger 17 and the first heat exchanger 13 in sequence and flow into the interior of the vehicle, thereby achieving heating of the interior of the vehicle.

[0233] When dehumidification is required during the heating mode operation of the vehicle interior, the seventh control device 72 may expand the refrigerant having passed through the first heat exchanger 13 and supply the expanded refrigerant to the fourth heat exchanger 17 .

[0234] Then, the air introduced into the HVAC module 12 is dehumidified by the refrigerant in a low temperature state introduced into the fourth heat exchanger 17 while passing through the fourth heat exchanger 17. Thereafter, since the air is converted into a high temperature state while passing through the first heat exchanger 13 and then introduced into the vehicle interior, the vehicle interior can be smoothly heated and dehumidified.

[0235] Therefore, as described above, when the heat pump system for a vehicle according to the embodiment is applied, since cooling or heating of the vehicle interior is performed by using a natural refrigerant, it is possible to cope with the requirements of environmental regulations and improve the overall marketability of the vehicle.

[0236] In addition, according to the present invention, by applying R744 refrigerant as a natural refrigerant using carbon dioxide, it is possible to maximize cooling and heating performance by operating in a supercritical region, which is a state where the pressure and temperature of the refrigerant are higher than a threshold pressure and temperature, and can be used for cooling and heating the interior of the vehicle.

[0237] Furthermore, according to the present invention, by using a single cooler 30 , heat exchange of the coolant and the refrigerant based on the vehicle mode can effectively adjust the temperature of the battery module 5 , thereby enabling streamlining and simplification of the system.

[0238] Furthermore, according to the embodiment, by effectively regulating the temperature of the battery module 5 , optimal performance of the battery module 5 may be achieved, and the overall driving distance of the vehicle may be increased due to the effective management of the battery module 5 .

[0239] In addition, in the heating mode of the vehicle interior, according to the present invention, since the refrigerant is branched through the branch line 53 and provided to the second heat exchanger 14 and the third heat exchanger 15 after expansion, the flow of the refrigerant can be easily controlled, the ambient air heat and the waste heat of the electrical components 3 can be smoothly recovered, and the cooler 30 can be optimally designed to cool the battery module 5.

[0240] Furthermore, according to the embodiment, it is possible to reduce manufacturing cost and weight, and improve space utilization by simplifying the entire system.

[0241] While the present invention has been described in conjunction with what are presently considered to be practical embodiments, it is to be understood that the invention is not limited to the disclosed embodiments but rather encompasses various modifications and equivalents within the spirit and scope thereof.

Claims

1. A heat pump system for a vehicle, comprising: an air conditioning unit including a compressor, a second heat exchanger, a third heat exchanger, and a fourth heat exchanger connected by a refrigerant line so that a refrigerant circulates through the refrigerant line; and a cooler connected to the refrigerant line through a second connecting line and configured to perform heat exchange between the refrigerant supplied from the air conditioning unit and the coolant to adjust the temperature of the coolant, Wherein, the air conditioning unit further comprises: a first control device disposed in the refrigerant line downstream of the compressor; a first heat exchanger connected to the first control device via a first connecting pipeline; a second control device, arranged upstream of the cooler and the fourth heat exchanger, at a location where the refrigerant pipeline is connected to the second connecting pipeline; a third control device, disposed in the refrigerant pipeline between the fourth heat exchanger and the compressor; A third connecting pipeline includes: a first end connected to the refrigerant pipeline between the fourth heat exchanger and the third control device; and a second end connected to the refrigerant pipeline between the third heat exchanger and the second control device; and The fourth control device is arranged in the third connecting pipeline.

2. The heat pump system according to claim 1, wherein: The first control device comprises: a first valve disposed in the refrigerant line between the compressor and the second heat exchanger; and A second valve is provided in the first connecting line between the compressor and the first heat exchanger.

3. The heat pump system according to claim 2, wherein: The first valve and the second valve are two-way valves.

4. The heat pump system according to claim 1, wherein: The first control device comprises: A single control valve is provided at a portion where the refrigerant line and the first connecting line are connected.

5. The heat pump system according to claim 1, wherein: The second control device comprises: a first expansion valve disposed in the refrigerant line upstream of the fourth heat exchanger; and A second expansion valve is disposed in the second connecting line upstream of the cooler.

6. The heat pump system according to claim 1, wherein: The air conditioning unit further comprises: A branch pipeline, comprising: a first end connected to the refrigerant pipeline between the first control device and the second heat exchanger; and a second end connected to the third connecting pipeline; a fifth control device, arranged in the branch pipeline; a fourth connecting pipeline, comprising: a first end connected to the refrigerant pipeline between the second heat exchanger and the third heat exchanger; and a second end connected to the refrigerant pipeline between the third control device and the compressor; a sixth control device, disposed in the fourth connecting pipeline; and A seventh control device is arranged in the first connecting pipeline.

7. The heat pump system according to claim 6, wherein: The third control device and the sixth control device are two-way valves.

8. The heat pump system according to claim 6, wherein: The fourth control device, the fifth control device, and the seventh control device are expansion valves.

9. The heat pump system according to claim 6, wherein: In the cooling mode of the vehicle interior, The refrigerant line connecting the fourth heat exchanger and the compressor is opened by operation of the third control device; The refrigerant line connecting the compressor and the second heat exchanger is opened by operation of the first control device; The first connecting pipeline is closed by the operation of the first control device and the seventh control device; The third connecting pipeline is closed by operation of the fourth control device; The branch line is closed by operation of the fifth control device; and The fourth connecting line is closed by operation of the sixth control device.

10. The heat pump system according to claim 9, wherein: In a cooling mode for the interior of the vehicle, when cooling of the battery module is required, the second connecting line is opened by operation of the second control device.

11. The heat pump system according to claim 10, wherein: The second control device is configured to expand the refrigerant introduced into the second connecting line and flow the expanded refrigerant to the cooler, thereby cooling the battery module by exchanging heat with the refrigerant using the coolant in the cooler.

12. The heat pump system according to claim 6, wherein: In vehicle interior heating mode: the refrigerant line connecting the third heat exchanger and the fourth heat exchanger is closed by operation of the second control device; a portion of the refrigerant line connecting the compressor and the third control device is closed by operation of the third control device; a portion of the refrigerant line connecting the first control device and the second heat exchanger is closed by operation of the first control device; The first connecting line is opened by operation of the first control device; The first connecting line is connected to the refrigerant line upstream of the fourth heat exchanger by operation of the seventh control device; The second connecting pipeline is closed by operation of the second control device; The third connecting line is opened by operation of the fourth control device; The branch line is opened by operation of the fifth control device; and The fourth connecting line is opened by operation of the sixth control device.

13. The heat pump system according to claim 12, wherein: The fourth control device is configured to expand the refrigerant so that the expanded refrigerant is supplied to the third heat exchanger; and The fifth control device is configured to expand the refrigerant so that the expanded refrigerant is supplied to the second heat exchanger.

14. The heat pump system according to claim 12, wherein: A portion of the refrigerant introduced from the fourth heat exchanger into the third connecting line is introduced into the second heat exchanger through the branch line; and The remaining refrigerant is introduced into the third heat exchanger.

15. The heat pump system according to claim 12, wherein: The refrigerant discharged from the second heat exchanger and the third heat exchanger is supplied to the compressor along the fourth connecting line.

16. The heat pump system according to claim 12, wherein: The seventh control device is configured to supply the refrigerant introduced through the first connecting line to the fourth heat exchanger in an unexpanded state.

17. The heat pump system according to claim 12, wherein: In heating mode of the vehicle interior, when dehumidification is required: The seventh control device is configured to expand the refrigerant introduced through the first connecting line and supply the expanded refrigerant to the fourth heat exchanger.

18. The heat pump system according to claim 6, wherein: The second, third, and fourth heat exchangers are configured to cool or evaporate refrigerant according to respective selective operations of the second, fourth, fifth, and seventh control devices.

19. The heat pump system according to claim 1, wherein: The refrigerant is R744 refrigerant formed of carbon dioxide.

20. The heat pump system according to claim 1, wherein: An accumulator is provided in the refrigerant line between the fourth heat exchanger and the compressor.

21. The heat pump system according to claim 1, wherein: The second heat exchanger is connected to the electrical component via a first pipeline through which a coolant circulates; and The cooler is connected to the battery module through a second line through which a coolant circulates.

22. The heat pump system according to claim 1, wherein: The first heat exchanger, the third heat exchanger, and the fourth heat exchanger are air-cooled gas coolers configured to perform heat exchange between a refrigerant and air; and The second heat exchanger and the cooler are water-cooled gas coolers configured to perform heat exchange between a refrigerant and a coolant.

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