Heat management system for vehicle

Abstract

An embodiment provides a heat management system for a vehicle, the system comprising: a compressor for compressing a refrigerant and discharging the refrigerant to a refrigerant line; a condenser for condensing the refrigerant discharged from the compressor; an evaporator disposed inside an air conditioning case together with the condenser and heat-exchanging the refrigerant having passed through the condenser with a heat medium; a plurality of heat exchangers disposed outside the air conditioning case and heat-exchanging the refrigerant having passed through the evaporator or refrigerant having passed through the condenser with the heat medium; and a first expansion valve disposed between the condenser and the evaporator in the refrigerant line, wherein the degree of expansion of the refrigerant is controlled differently in the first expansion valve according to a heating load.

Description

Thermal management system for vehicles

[0001] The present invention relates to a thermal management system for a vehicle.

[0002] Automotive air conditioning systems utilize heat pump systems that utilize a refrigerant cycle to selectively cool and heat the vehicle's interior. For example, an indoor heat exchanger is installed inside the air conditioning case, while an outdoor heat exchanger is installed outside. The outdoor heat exchanger acts as an evaporator, absorbing heat from the outside air, while the indoor heat exchanger acts as a condenser, dissipating heat to heat the vehicle's interior.

[0003] In these heat pump systems, sufficient heating capacity is difficult to achieve when the outside temperature is low during heating operation. In such cases, the proportion of gaseous refrigerant in the refrigerant condensing in the indoor heat exchanger and flowing to the outdoor heat exchanger increases. Even if this gaseous refrigerant is supplied to the outdoor heat exchanger, it largely fails to contribute to the heat absorption process from the outside air. Therefore, methods to improve the performance and efficiency of heat pump systems are being sought, and research into these areas is ongoing.

[0004] The problem to be solved by the present invention is to provide a vehicle thermal management system capable of improving cooling and heating performance.

[0005] The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

[0006] A vehicle thermal management system according to an embodiment of the present invention includes a compressor that compresses a refrigerant and discharges it into a refrigerant line, a condenser that condenses the refrigerant discharged from the compressor, an evaporator that is disposed inside an air conditioning case together with the condenser and exchanges heat with a heat medium of the refrigerant that has passed through the condenser, a heat exchanger that is disposed outside the air conditioning case and exchanges heat with the refrigerant that has passed through the evaporator or the refrigerant that has passed through the condenser, and a first expansion valve that is disposed between the condenser and the evaporator in the refrigerant line, and is characterized in that the degree of expansion of the refrigerant is controlled differently in the first expansion valve according to a heating load.

[0007] The above heat exchanger may include at least one of an outdoor heat exchanger that uses outside air as the heat medium, a water-cooled heat exchanger that uses cooling water as the heat medium, and a chiller.

[0008] The above refrigerant line may include a first line in which the compressor, the condenser, the evaporator, and the outdoor heat exchanger are arranged, a second line connected in parallel to the first line and in which the water-cooled heat exchanger is arranged, a third line connecting the first line and the second line, a fourth line connected in parallel to the first line and in which the chiller is arranged, and a fifth line connecting the first line and the fourth line.

[0009] It may further include a second expansion valve arranged in the first line.

[0010] The second line may be connected at one end to the inlet side of the outdoor heat exchanger from the first line, and at the other end to the rear end of the outlet side of the outdoor heat exchanger.

[0011] The third line may have one end connected to the rear end of the outlet side of the condenser in the first line, and the other end connected to the front end of the inlet side of the water-cooled heat exchanger in the second line.

[0012] It may further include a third expansion valve arranged in the third line.

[0013] The fourth line may have one end connected between the evaporator and the outdoor heat exchanger in the first line, and the other end connected to the inlet end of the compressor.

[0014] It further includes a fourth expansion valve arranged in the fourth line, and the fourth expansion valve can be arranged at the inlet side end of the chiller in the fourth line.

[0015] The fifth line may have one end connected between the condenser and the evaporator in the first line, and the other end connected to the rear end of the outlet side of the chiller in the fourth line.

[0016] The first line may further include an accumulator arranged at the inlet side of the compressor.

[0017] A two-way valve may be arranged between the compressor and the condenser in the first line, between the evaporator and the outdoor heat exchanger, between the outdoor heat exchanger and the compressor, and in the second line and the fifth line, respectively.

[0018] The heating mode is configured so that the refrigerant passing through the condenser passes through the evaporator or bypasses the evaporator depending on the heating load, and the heating mode in which the refrigerant passes through the evaporator can operate under conditions in which the heating load is relatively greater than the heating mode in which the refrigerant bypasses the evaporator.

[0019] In the heating mode in which the refrigerant passes through the evaporator, the degree of expansion of the refrigerant by the first expansion valve is controlled differently depending on the heating load. When the heating load is relatively large, the refrigerant can be controlled to expand to an intermediate pressure, and when the heating load is relatively small, the refrigerant can be controlled to pass in a non-expanded state.

[0020] In a heating mode in which the refrigerant bypasses the evaporator, the refrigerant may be configured to expand while passing through the third expansion valve and then exchange heat with the heat medium in the water-cooled heat exchanger, or to expand while passing through the fourth expansion valve and then exchange heat with the heat medium in the chiller.

[0021] The dehumidification mode is configured so that the refrigerant passing through the condenser passes through the evaporator or bypasses the evaporator depending on the dehumidification load, and the dehumidification mode in which the refrigerant bypasses the evaporator can operate under conditions in which the dehumidification load is relatively greater than the dehumidification mode in which the refrigerant passes through the evaporator.

[0022] In the dehumidification mode in which the refrigerant bypasses the evaporator, the refrigerant may be configured to pass through the third expansion valve in a non-expanded state, then exchange heat with the heat medium while passing through at least one of the water-cooled heat exchanger and the outdoor heat exchanger, and then expand while passing through the second expansion valve and then pass through the evaporator.

[0023] In the dehumidification mode in which the refrigerant passes through the evaporator, the refrigerant may be configured to expand while passing through the first expansion valve and then exchange heat with the heat medium while passing through at least one of the evaporator, the outdoor heat exchanger, and the water-cooled heat exchanger.

[0024] In the dehumidification mode in which the refrigerant passes through the evaporator, the refrigerant may be configured to expand while passing through the first expansion valve, then exchange heat with the heat medium while passing through the evaporator, and then exchange heat with the heat medium while passing through the second expansion valve and the fourth expansion valve in a non-expanded state and then passing through the chiller.

[0025] According to an embodiment of the present invention, a vehicle thermal management system capable of improving cooling and heating performance can be provided.

[0026] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0027] FIG. 1 is a schematic diagram illustrating a vehicle thermal management system according to an embodiment of the present invention.

[0028] Figure 2 is a drawing showing the operation in the first heating mode of the vehicle thermal management system.

[0029] Figure 3 is a drawing showing the operation in the second heating mode of the vehicle thermal management system.

[0030] Figure 4 is a drawing showing the operation in the third heating mode of the vehicle thermal management system.

[0031] Figure 5 is a drawing showing the operation in the fourth heating mode of the vehicle thermal management system.

[0032] Figure 6 is a drawing showing the operation in the first dehumidification mode of the vehicle thermal management system.

[0033] Figure 7 is a drawing showing the operation in the second dehumidification mode of the vehicle thermal management system.

[0034] Figure 8 is a drawing showing the operation in the third dehumidification mode of the vehicle thermal management system.

[0035] The present invention is susceptible to various modifications and embodiments, and specific embodiments are illustrated and described in the drawings. However, this is not intended to limit the present invention to specific embodiments, but should be understood to include all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention. Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a second component may be referred to as a first component, and similarly, a first component may also be referred to as a second component. The term and / or includes a combination of a plurality of related described items or any of a plurality of related described items.

[0036] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0037] In the description of embodiments, when one component is described as being formed "on or under" another component, "on or under" includes both cases where the two components are in direct contact with each other or where one or more other components are formed indirectly between the two components. In addition, when expressed as "on or under," it can include the meaning of not only the upward direction but also the downward direction based on one component.

[0038] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprise" or "have" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0039] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0040] Hereinafter, embodiments will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or corresponding components are given the same reference numbers, and redundant descriptions thereof will be omitted.

[0041] Vehicles are equipped with air conditioning systems to control air temperature, humidity, cleanliness, and ventilation, creating a comfortable environment inside the vehicle. Here, the air conditioning system can be referred to as HVAC (Heating / Ventilation / Air Conditioning).

[0042] When a vehicle uses a fuel cell or other power source, the vehicle may be equipped with a separate battery coolant circulation system capable of cooling the battery. The vehicle may be an electric vehicle or a fuel cell vehicle.

[0043] Accordingly, the vehicle thermal management system according to the embodiment can improve thermal management efficiency by implementing a heat pump structure in the air conditioning unit that utilizes heat (hereinafter referred to as "waste heat") wasted in the coolant circulation structure of the battery and electrical components. Here, the electrical components may include a motor, inverter, Lidar, radar, sensors, etc. installed in the vehicle.

[0044] That is, the vehicle thermal management system according to the embodiment can improve the cooling and heating performance and quality inside the vehicle by utilizing waste heat according to the air conditioning mode.

[0045] Meanwhile, a vehicle thermal management system according to an embodiment can provide a vehicle thermal management system having a compact size while improving cooling and heating performance by controlling a vapor injection module including a plurality of expansion means and a single gas-liquid separator and a heat exchange medium passing through the vapor injection module. Here, the expansion means may include an expansion valve.

[0046] Furthermore, the vehicle thermal management system according to the embodiment can optimize the flow of heat exchange medium by presenting an optimized arrangement relationship between the components of the vapor injection module. Accordingly, the vehicle thermal management system can further improve cooling and heating performance.

[0047] FIG. 1 is a schematic diagram illustrating a vehicle thermal management system according to an embodiment of the present invention.

[0048] Referring to the drawings, a vehicle thermal management system (1) according to an embodiment of the present invention may include a compressor (10), a condenser (20), an evaporator (30), a heat exchanger (40, 50, 60), and a plurality of valves (100). In addition, an accumulator (70) may be further included.

[0049] The compressor (10), condenser (20), evaporator (30), and heat exchanger (40, 50, 60) can be placed and connected to a refrigerant line (L) through which refrigerant circulates.

[0050] The heat exchanger (40, 50, 60) is configured to exchange heat between the refrigerant that has passed through the evaporator (30) or the refrigerant that has passed through the condenser (20) and the heat medium. In an embodiment, the heat exchanger (40, 50, 60) may include an outdoor heat exchanger (40), a water-cooled heat exchanger (50), and a chiller (60) that are arranged outside the air conditioning case (AC). In the present embodiment, the outdoor heat exchanger (40), the water-cooled heat exchanger (50), and the chiller (60) are all included, but this is not limited thereto. That is, it is also possible to include at least one of the outdoor heat exchanger (40), the water-cooled heat exchanger (50), and the chiller (60).

[0051] The plurality of valves (100) may include a first expansion valve (110), a second expansion valve (120), a third expansion valve (130), and a fourth expansion valve (140).

[0052] The refrigerant line (L) can be configured so that the refrigerant discharged from the compressor (10) passes through the condenser (20), the evaporator (30), and a number of heat exchangers (40, 50, 60), then passes through the accumulator (70) and circulates back to the compressor (10).

[0053] The refrigerant line (L) may include a first line (L1) in which a compressor (10), a condenser (20), an evaporator (30), and an outdoor heat exchanger (40) are arranged, a second line (L2) connected in parallel to the first line (L1) and in which a water-cooled heat exchanger (50) is arranged, a third line (L3) connecting the first line (L1) and the second line (L2), a fourth line (L4) connected in parallel to the first line (L1) and in which a chiller (60) is arranged, and a fifth line (L5) connecting the first line (L1) and the fourth line (L4).

[0054] The first expansion valve (110) and the second expansion valve (120) may be arranged in the first line (L1). The third expansion valve (130) may be arranged in the third line (L3), and the fourth expansion valve (140) may be arranged in the fourth line (L4).

[0055] The compressor (10) can compress the refrigerant and discharge it through the first line (L1). The compressor (10) is driven by power transmitted from an engine (internal combustion engine) or a motor, etc., and compresses the introduced refrigerant and discharges it in a high-temperature, high-pressure gaseous state.

[0056] The condenser (20) can condense the refrigerant discharged from the compressor (10). The condenser (20) is placed inside the air conditioning case (AC) and can exchange heat between the air flowing inside the air conditioning case (AC) and the refrigerant. The air is heated in the condenser (20) and flows into the vehicle to heat the interior of the vehicle.

[0057] The evaporator (30) is placed inside the air conditioning case (AC) together with the condenser (20), and can exchange heat with the refrigerant that has passed through the condenser (20) and the heat medium. That is, the heat medium that exchanges heat with the refrigerant may be air flowing inside the air conditioning case (AC), and the air that has exchanged heat with the refrigerant is introduced into the vehicle to heat the interior of the vehicle.

[0058] The outdoor heat exchanger (40) is arranged in a structure in series with the evaporator (30) in the first line (L1) and can exchange heat with the refrigerant and heat medium introduced along the first line (L1). In an embodiment, the outdoor heat exchanger (L1) may include an air-cooled condenser, and outside air may be used as the heat medium that exchanges heat with the refrigerant.

[0059] In an embodiment, an internal heat exchanger (80) may be further arranged between the outdoor heat exchanger (40) and the evaporator (30) in the first line (L1).

[0060] An accumulator (70) can be placed at the inlet end of the compressor (10) in the first line (L1). When refrigerant flows in along the first line (L1), the accumulator (70) can separate the refrigerant into gas and liquid and supply the gaseous refrigerant to the compressor (10).

[0061] The water-cooled heat exchanger (50) and chiller (60) can each be connected in parallel to the first line (L1).

[0062] A water-cooled heat exchanger (50) may be arranged in a second line (L2) and connected in parallel to the first line (L1). The second line (L2) may be provided with a structure in which one end is connected to the inlet-side front end of the outdoor heat exchanger (40) in the first line (L1) and the other end is connected to the outlet-side rear end of the outdoor heat exchanger (40). Accordingly, the refrigerant may pass through the outdoor heat exchanger (40) along the first line (L1), and some of the refrigerant may branch off and pass through the water-cooled heat exchanger (50) along the second line (L2).

[0063] The water-cooled heat exchanger (50) can heat-exchange the refrigerant introduced along the second line (L2) with the heat medium. In an embodiment, the water-cooled heat exchanger (50) can heat-exchange the refrigerant with the cooling water passing through the vehicle's electrical components (not shown). That is, the cooling water can be used as the heat medium that exchanges heat with the refrigerant in the water-cooled heat exchanger (50). Accordingly, the vehicle's thermal management system (1) can perform heating by utilizing the waste heat of the electrical components as a heat source.

[0064] The chiller (60) may be arranged on the fourth line (L4) and connected in parallel to the first line (L1). One end of the fourth line (L4) may be connected between the evaporator (30) and the outdoor heat exchanger (50) in the first line (L1), and the other end may be connected to the inlet end of the compressor (10). Accordingly, the refrigerant that has passed through the evaporator (30) along the first line (L1) may move along the fourth line (L4) and pass through the chiller (60).

[0065] The chiller (60) can heat-exchange the refrigerant and heat medium introduced along the fourth line (L4). In an embodiment, the chiller (60) can heat-exchange the refrigerant and the coolant passing through the vehicle's battery (not shown). That is, the coolant can be used as the heat medium that exchanges heat with the refrigerant in the chiller (60). Accordingly, the vehicle's thermal management system (1) can perform heating using the waste heat of the battery as a heat source.

[0066] Meanwhile, the third line (L3) may be connected at one end to the rear end of the outlet side of the condenser (20) from the first line (L1), and at the other end to the front end of the inlet side of the water-cooled heat exchanger (50) from the second line (L2). Accordingly, the refrigerant passing through the condenser (20) may flow into the evaporator (30) along the first line (L1), or may branch off from the first line (L1) and move along the third line (L3) and then move to the second line (L2).

[0067] The fifth line (L5) may be connected at one end between the condenser (20) and the evaporator (30) in the first line (L1), and at the other end connected to the rear end of the outlet side of the chiller (60) in the fourth line (L4). Accordingly, the refrigerant that has passed through the evaporator (30) may branch off from the first line (L1) and flow to the fourth line (L4) via the fifth line (L5).

[0068] The first expansion valve (110) may be arranged between the condenser (20) and the evaporator (30) in the first line (L1). The first expansion valve (110) may perform expansion, flow control, and opening / closing functions of the refrigerant discharged from the condenser (20) and moving along the first line (L1). In particular, by controlling the degree of refrigerant expansion in the first expansion valve (110) differently according to the heating load, the temperature of the air supplied to the room can be increased.

[0069] In an embodiment, the first expansion valve (110) may be an electronic two-way expansion valve or an electronic three-way expansion valve. If the first expansion valve (110) is provided as an electronic three-way expansion valve, the fifth line (L5) may be connected to the first line (L1) via the first expansion valve (110).

[0070] The second expansion valve (120) may be arranged between the evaporator (30) and the outdoor heat exchanger (40) in the first line (L1). The second expansion valve (120) may perform expansion, flow control, and opening / closing functions of the refrigerant passing through the evaporator (30) and moving to the outdoor heat exchanger (40) along the first line (L1) or of the refrigerant passing through the outdoor heat exchanger (40) and moving to the evaporator (30) along the first line (L1).

[0071] In an embodiment, the second expansion valve (120) may be an electronic two-way expansion valve or an electronic three-way expansion valve. When the second expansion valve (120) is provided as an electronic three-way expansion valve, the fourth line (L4) may be connected to the first line (L1) via the second expansion valve (120).

[0072] The third expansion valve (130) may be positioned in the third line (L3). The third expansion valve (130) may perform expansion, flow control, and opening / closing functions of the refrigerant passing through the condenser (20) and moving along the third line (L3). In an embodiment, the third expansion valve (130) may be an electronic two-way expansion valve.

[0073] The fourth expansion valve (140) may be placed at the inlet end of the chiller (60) in the fourth line (L4). The fourth expansion valve (140) may perform expansion, flow control, and opening / closing functions of the refrigerant moving to the chiller (60) along the fourth line (L4). In an embodiment, the fourth expansion valve (140) may be an electronic 2-way expansion valve.

[0074] In addition, a 2-way valve (200) may be arranged between the compressor (10) and the condenser (20), between the evaporator (30) and the outdoor heat exchanger (40), and between the outdoor heat exchanger (40) and the compressor (10) in the first line (L1). In addition, it may be arranged at the inlet end of the water-cooled heat exchanger (50) in the second line (L2) and in the fifth line (L5). This 2-way valve (200) can perform the flow control and opening / closing functions of the refrigerant without an expansion function.

[0075] Below, the operation of each air conditioning mode of the vehicle thermal management system (1) according to the embodiment of the present invention described above will be described.

[0076] Figure 2 is a diagram showing operation in the first heating mode. The first heating mode operates when the heating load is relatively large.

[0077] Referring to Fig. 2, the compressor (10) operates and high-temperature, high-pressure refrigerant is discharged from the compressor (10). The refrigerant discharged from the compressor (10) moves along the first line (L1). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the condenser (20), and the heated air is supplied as warm air into the vehicle interior to perform heating. In other words, primary heat dissipation is performed in the condenser (20).

[0078] The refrigerant passing through the condenser (20) moves along the first line (L1), expands to an intermediate pressure while passing through the first expansion valve (110), and then flows into the evaporator (30). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the evaporator (30). That is, secondary heat radiation occurs in the evaporator (30). At this time, as the refrigerant expands to an intermediate pressure in the first expansion valve (110), Pd / Td increases, which can increase the temperature of the air discharged into the vehicle interior. In addition, as secondary heat radiation occurs in the evaporator (30), more heated air can be introduced into the vehicle interior.

[0079] The refrigerant passing through the evaporator (30) expands while passing through the second expansion valve (120) and moves along the first line (L1), and exchanges heat with the heat medium (heat absorption) while passing through the outdoor heat exchanger (40) or the water-cooled heat exchanger (50) or the outdoor heat exchanger (40) and the water-cooled heat exchanger (50). Then, it passes through the accumulator (70) and flows back into the compressor (10).

[0080] In this way, heat dissipation is performed twice through the condenser (20) and the evaporator (30), waste heat from the electrical components is recovered through the water-cooled heat exchanger (50), and heat absorption from the outside air is performed through the outdoor heat exchanger (40), thereby improving heating performance.

[0081] Figure 3 is a diagram showing operation in the second heating mode. The second heating mode operates when the heating load is relatively small compared to the first heating mode.

[0082] Referring to Fig. 3, the compressor (10) operates to discharge high-temperature, high-pressure refrigerant from the compressor (10). The refrigerant discharged from the compressor (10) moves along the first line (L1). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the condenser (20), and the heated air is supplied as warm air into the vehicle interior to perform heating. In other words, primary heat dissipation is performed in the condenser (20).

[0083] The refrigerant passing through the condenser (20) moves along the first line (L1) and flows into the evaporator (30) through the first expansion valve (110) in a fully open state. That is, the first expansion valve (110) is controlled so that the refrigerant passes in a non-expanded state. Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the evaporator (30). That is, secondary heat dissipation takes place in the evaporator (30).

[0084] The refrigerant passing through the evaporator (30) expands while passing through the second expansion valve (120) and moves along the first line (L1), and exchanges heat with the heat medium (heat absorption) while passing through the outdoor heat exchanger (40) or the water-cooled heat exchanger (50) or the outdoor heat exchanger (40) and the water-cooled heat exchanger (50). Then, it passes through the accumulator (70) and flows back into the compressor (10).

[0085] In this way, heat dissipation is performed twice through the condenser (20) and the evaporator (30), waste heat from the electrical components is recovered through the water-cooled heat exchanger (50), and heat absorption from the outside air is performed through the outdoor heat exchanger (40), thereby improving heating performance.

[0086] Figure 4 is a diagram showing operation in the third heating mode. The third heating mode operates when the heating load is small.

[0087] Referring to Fig. 4, the compressor (10) operates and high-temperature, high-pressure refrigerant is discharged from the compressor (10). The refrigerant discharged from the compressor (10) moves along the first line (L1). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the condenser (20), and the heated air is supplied as warm air into the vehicle interior to perform heating.

[0088] The refrigerant that has passed through the condenser (20) moves along the third line (L3) branched off from the first line (L1), expands while passing through the third expansion valve (130), and then moves along the second line (L2) and flows into the water-cooled heat exchanger (50). That is, it moves by bypassing the evaporator (30).

[0089] The refrigerant exchanges heat with the cooling water (heat absorption) while passing through the water-cooled heat exchanger (50), moves along the first line (L1), passes through the accumulator (70), and is then introduced into the compressor (10) again.

[0090] In this way, heat dissipation is performed in the condenser (20) and the waste heat of the electrical components is recovered through the water-cooled heat exchanger (50), thereby heating the interior of the vehicle.

[0091] Figure 5 is a diagram showing operation in the fourth heating mode. The fourth heating mode operates when the heating load is small, like the third heating mode.

[0092] Referring to Fig. 5, the compressor (10) operates and high-temperature, high-pressure refrigerant is discharged from the compressor (10). The refrigerant discharged from the compressor (10) moves along the first line (L1). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the condenser (20), and the heated air is supplied as warm air into the vehicle interior to perform heating.

[0093] The refrigerant that has passed through the condenser (20) moves along the third line (L3) branched off from the first line (L1), passes through the third expansion valve (130) in a non-expanded state, and then moves along the second line (L2) and the first line (L1). That is, it moves bypassing the water-cooled heat exchanger (50) and the outdoor heat exchanger (40).

[0094] The refrigerant moves along the fourth line (L4) branched from the first line (L1), expands while passing through the fourth expansion valve (140), and then flows into the chiller (60). Then, while passing through the chiller (60), it exchanges heat with the cooling water (heat absorption), moves along the first line (L1), passes through the accumulator (70), and flows back into the compressor.

[0095] In this way, heat dissipation is achieved in the condenser (20) and the waste heat of the battery is recovered through the chiller (60), thereby heating the interior of the vehicle.

[0096] Figure 6 is a diagram showing operation in the first dehumidification mode. The first dehumidification mode operates when the dehumidification load is relatively large.

[0097] Referring to Fig. 6, the compressor (10) operates and high-temperature, high-pressure refrigerant is discharged from the compressor (10). The refrigerant discharged from the compressor (10) moves along the first line (L1). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the condenser (20), and the heated air is supplied as warm air into the vehicle interior to perform heating.

[0098] The refrigerant that has passed through the condenser (20) moves along the third line (L3) branched from the first line (L1), passes through the third expansion valve (130) in a non-expanded state, and then moves along the second line (L2) and flows into the water-cooled heat exchanger (50). That is, it moves by bypassing the evaporator (30).

[0099] The refrigerant exchanges heat with the cooling water (heat dissipation) while passing through the water-cooled heat exchanger (50), moves along the first line (L1), and flows into the outdoor heat exchanger (40). Then, heat is exchanged with the outside air (heat dissipation) while passing through the outdoor heat exchanger (40).

[0100] The refrigerant, which has passed through the water-cooled heat exchanger (50) and the outdoor heat exchanger (40) and has its temperature lowered, is expanded through the second expansion valve (120) and then flows into the evaporator (30). Then, the refrigerant that has passed through the evaporator (30) moves along the fifth line (L5) branched off from the first line (L1), and flows into the compressor (10) again through the accumulator (70) in the first line (L1).

[0101] In this way, the dehumidification performance can be improved by sufficiently lowering the temperature of the refrigerant as it passes through the water-cooled heat exchanger (50) and the outdoor heat exchanger (40).

[0102] Figure 7 is a diagram showing operation in the second dehumidification mode. The second dehumidification mode operates when the dehumidification load is relatively small compared to the first dehumidification mode.

[0103] Referring to Fig. 7, the compressor (10) operates and high-temperature, high-pressure refrigerant is discharged from the compressor (10). The refrigerant discharged from the compressor (10) moves along the first line (L1). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the condenser (20), and the heated air is supplied as warm air into the vehicle interior to perform heating. In other words, heat dissipation is performed in the condenser (20).

[0104] The refrigerant passing through the condenser (20) moves along the first line (L1), expands while passing through the first expansion valve (110), and then flows into the evaporator (30). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the evaporator (30). At this time, heat absorption occurs in the evaporator (30).

[0105] The refrigerant passing through the evaporator (30) passes through the second expansion valve (120) in a non-expanded state and moves along the first line (L1), and exchanges heat with the heat medium while passing through the outdoor heat exchanger (40) or the water-cooled heat exchanger (50) or the outdoor heat exchanger (40) and the water-cooled heat exchanger (50). At this time, heat absorption occurs in the outdoor heat exchanger (40) and the water-cooled heat exchanger (50). Then, it passes through the accumulator (70) and flows back into the compressor (10).

[0106] Figure 8 is a drawing showing operation in the third dehumidification mode.

[0107] Referring to Fig. 8, the compressor (10) operates to discharge high-temperature and high-pressure refrigerant from the compressor (10). The refrigerant discharged from the compressor (10) moves along the first line (L1). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the condenser (20), and the heated air is supplied as warm air into the vehicle interior to perform heating. In other words, heat dissipation occurs in the condenser (20).

[0108] The refrigerant passing through the condenser (20) moves along the first line (L1), expands while passing through the first expansion valve (110), and then flows into the evaporator (30). Then, the refrigerant exchanges heat with the air flowing inside the air conditioning case (AC) while passing through the evaporator (30). At this time, heat absorption occurs in the evaporator (30).

[0109] The refrigerant that has passed through the evaporator (30) passes through the second expansion valve (120) in a non-expanded state, then moves along the fourth line (L4) branched from the first line (L1), and then passes through the fourth expansion valve (140) in a non-expanded state and then flows into the chiller (60).

[0110] The refrigerant exchanges heat with the cooling water as it passes through the chiller (60). At this time, additional heat absorption occurs in the chiller (60). Then, it passes through the accumulator (70) and flows back into the compressor (10). If additional heat absorption is unnecessary, the flow of the cooling water passing through the chiller (60) is blocked to prevent heat exchange with the refrigerant.

[0111] While the present invention has been described above with reference to specific embodiments, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention as defined in the claims below. Furthermore, any differences resulting from such modifications and variations should be construed as being within the scope of the present invention as defined in the appended claims.

Claims

1. A compressor that compresses the refrigerant and discharges it into the refrigerant line; A condenser that condenses the refrigerant discharged from the compressor; An evaporator arranged inside an air conditioning case together with the above condenser and exchanging heat between the refrigerant passing through the condenser and a heat medium; A heat exchanger, which is placed outside the air conditioning case and exchanges heat between the refrigerant that has passed through the evaporator or the refrigerant that has passed through the condenser and the heat medium; and A first expansion valve disposed between the condenser and the evaporator in the refrigerant line; Including, A vehicle thermal management system characterized in that the degree of expansion of the refrigerant in the first expansion valve is controlled differently depending on the heating load.

2. In paragraph 1, A vehicle thermal management system including at least one of an outdoor heat exchanger in which outside air is used as the heat medium, a water-cooled heat exchanger in which cooling water is used as the heat medium, and a chiller.

3. In paragraph 2, A vehicle thermal management system, wherein the refrigerant line comprises a first line in which the compressor, the condenser, the evaporator, and the outdoor heat exchanger are arranged, a second line connected in parallel to the first line and in which the water-cooled heat exchanger is arranged, a third line connecting the first line and the second line, a fourth line connected in parallel to the first line and in which the chiller is arranged, and a fifth line connecting the first line and the fourth line.

4. In paragraph 3, A vehicle thermal management system further comprising a second expansion valve disposed in the first line.

5. In paragraph 3, A vehicle heat management system, characterized in that one end of the second line is connected to the inlet-side front end of the outdoor heat exchanger from the first line, and the other end is connected to the outlet-side rear end of the outdoor heat exchanger.

6. In paragraph 3, A vehicle thermal management system, characterized in that one end of the third line is connected to the rear end of the outlet side of the condenser in the first line, and the other end is connected to the front end of the inlet side of the water-cooled heat exchanger in the second line.

7. In paragraph 4, A vehicle thermal management system further comprising a third expansion valve disposed in the third line.

8. In paragraph 3, A vehicle thermal management system, characterized in that the fourth line has one end connected between the evaporator and the outdoor heat exchanger in the first line, and the other end connected to the inlet-side terminal of the compressor.

9. In paragraph 7, A vehicle thermal management system further comprising a fourth expansion valve arranged in the fourth line, wherein the fourth expansion valve is arranged at an inlet-side front end of the chiller in the fourth line.

10. In paragraph 3, A vehicle thermal management system, characterized in that the fifth line has one end connected between the condenser and the evaporator in the first line, and the other end connected to the rear end of the outlet side of the chiller in the fourth line.

11. In paragraph 3, A vehicle thermal management system, characterized in that it further includes an accumulator arranged at the inlet side tip of the compressor in the first line.

12. In paragraph 3, A vehicle thermal management system, characterized in that a two-way valve is arranged between the compressor and the condenser in the first line, between the evaporator and the outdoor heat exchanger, between the outdoor heat exchanger and the compressor, in the second line, and in the fifth line, respectively.

13. In paragraph 9, The heating mode is configured so that the refrigerant passing through the condenser passes through the evaporator or bypasses the evaporator depending on the heating load. A vehicle thermal management system characterized in that the heating mode in which the refrigerant passes through the evaporator operates under conditions in which the heating load is relatively greater than that in the heating mode in which the refrigerant bypasses the evaporator.

14. In paragraph 13, A vehicle thermal management system characterized in that the degree of expansion of the refrigerant of the first expansion valve is controlled differently according to the heating load in the heating mode in which the refrigerant passes through the evaporator, and when the heating load is relatively large, the refrigerant is controlled to expand to an intermediate pressure, and when the heating load is relatively small, the refrigerant is controlled to pass in a non-expanded state.

15. In paragraph 13, A vehicle thermal management system characterized in that, in a heating mode in which the refrigerant bypasses the evaporator, the refrigerant is configured to expand while passing through the third expansion valve and then exchange heat with the heat medium in the water-cooled heat exchanger, or to expand while passing through the fourth expansion valve and then exchange heat with the heat medium in the chiller.

16. In paragraph 9, The dehumidification mode is configured so that the refrigerant passing through the condenser passes through the evaporator or bypasses the evaporator depending on the dehumidification load. A vehicle thermal management system characterized in that the dehumidification mode in which the refrigerant bypasses the evaporator operates under conditions in which the dehumidification load is relatively greater than the dehumidification mode in which the refrigerant passes through the evaporator.

17. In paragraph 16, A vehicle thermal management system characterized in that, in a dehumidifying mode in which the refrigerant bypasses the evaporator, the refrigerant passes through the third expansion valve in a non-expanded state, then exchanges heat with the heat medium while passing through at least one of the water-cooled heat exchanger and the outdoor heat exchanger, and then expands while passing through the second expansion valve and then passes through the evaporator.

18. In paragraph 16, A vehicle thermal management system characterized in that, in a dehumidifying mode in which the refrigerant passes through the evaporator, the refrigerant is expanded while passing through the first expansion valve and then exchanges heat with the heat medium while passing through at least one of the evaporator, the outdoor heat exchanger, and the water-cooled heat exchanger.

19. In Article 16, A vehicle thermal management system characterized in that, in a dehumidifying mode in which the refrigerant passes through the evaporator, the refrigerant is expanded while passing through the first expansion valve, then passes through the evaporator and exchanges heat with the heat medium, then passes through the second expansion valve and the fourth expansion valve in a non-expanded state, and then passes through the chiller and exchanges heat with the heat medium.

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