Vehicle thermal management system

Abstract

Disclosed is a vehicle thermal management system capable of performing all functions of an integrated thermal management system of an electric vehicle, reducing a package of an air conditioning device, and reducing manufacturing costs by using only three refrigerant valves. The vehicle thermal management system comprises: a compressor for compressing and discharging a refrigerant; an indoor heat exchanger provided inside an air conditioning case so as to heat air by exchanging heat with air discharged to the interior of a vehicle; an outdoor heat exchanger provided outside the air conditioning case so as to exchange heat with external air; an evaporator provided upstream of the indoor heat exchanger in an air flow direction inside the air conditioning case so as to cool air by exchanging heat with the air discharged to the interior of the vehicle; a chiller for heat exchange between the refrigerant and a coolant; a direction switching valve for controlling flow such that the refrigerant passing through the indoor heat exchanger flows to the outdoor heat exchanger or the evaporator; a first expansion valve capable of controlling the flow direction of the refrigerant and selectively expanding the refrigerant; and a second expansion valve disposed at a different position from the first expansion valve and capable of controlling the flow direction of the refrigerant and selectively expanding the refrigerant, wherein the first expansion valve and the second expansion valve are configured to enable a fully closed state that blocks the flow of the refrigerant.

Description

Thermal management system for vehicles

[0001] The present invention relates to a thermal management system for a vehicle, and more particularly, to a thermal management system for a vehicle installed in an electric vehicle or the like to perform air conditioning of the vehicle interior and integrated thermal management of a battery and electrical components.

[0002] Typically, a vehicle air conditioning system comprises a cooling system for cooling the vehicle's interior and a heating system for heating the interior. The cooling system is configured to cool the vehicle's interior by exchanging heat between refrigerant flowing through an evaporator and air passing through the evaporator. Furthermore, the heating system is configured to heat the vehicle's interior by exchanging heat between coolant flowing through a heater core and air passing through the heater core.

[0003] Recently, battery-powered vehicles, such as electric vehicles, have adopted vehicle heat pump systems that utilize a chiller that exchanges heat between coolant and refrigerant to cool the battery and the waste heat from the electrical components. Ultimately, heat pump performance is enhanced by recovering the air heat source through the outdoor unit and the waste heat from the electrical components and battery through the water-refrigerant heat exchanger (chiller).

[0004] Referring to Fig. 1, a conventional vehicle thermal management system (10) has a refrigerant circulation line (12). The refrigerant circulation line (12) has a compressor (12a), a high-pressure side indoor heat exchanger (12b), an expansion valve (12c) for a heat pump, a water-cooled heat exchanger (12d), a three-way valve (12e), an outdoor heat exchanger (12f), an expansion valve (12g) for an air conditioner, and a low-pressure side indoor heat exchanger (12h). The refrigerant circulation line (12) further has an expansion valve (14) for battery cooling and a chiller (16).

[0005] In cooling mode, the expansion valve (12c) for the heat pump is fully opened and the three-way valve (12e) is controlled toward the outdoor heat exchanger (12f). In heating mode, the expansion valve (12c) for the heat pump is turned ON to perform depressurization and expansion of the refrigerant and the three-way valve (12e) is controlled toward the compressor (12a). In addition, the refrigerant circulation line (12) is provided with a bypass line (18) and an on-off valve (19) that connect the outlet side of the expansion valve (12c) for the heat pump and the inlet side of the low-pressure indoor heat exchanger (12h).

[0006] Conventional vehicle thermal management systems require multiple refrigerant valves to manage the cooling, heating, dehumidification, battery, and electrical components of the vehicle interior. Implementing the aforementioned conventional thermal management system requires at least five refrigerant valves. This increases the overall system cost and increases the difficulty of system control.

[0007] In order to solve such conventional problems, the present invention provides a vehicle thermal management system that can perform all functions of an integrated thermal management system of an electric vehicle while reducing the package of an air conditioning unit and reducing manufacturing costs by using only three refrigerant valves.

[0008] A vehicle thermal management system according to the present invention comprises: a compressor that compresses and discharges a refrigerant; an indoor heat exchanger that is provided inside an air conditioning case and heats the air by exchanging heat with air discharged into the interior of a vehicle; an outdoor heat exchanger that is provided outside the air conditioning case and exchanges heat with outside air; an evaporator that is provided upstream of the indoor heat exchanger in the direction of air flow inside the air conditioning case and cools the air by exchanging heat with air discharged into the interior of the vehicle; a chiller that heat-exchanges the refrigerant with cooling water; a direction-changing valve that controls the flow of the refrigerant passing through the indoor heat exchanger so that it flows to the outdoor heat exchanger or the evaporator; a first expansion valve that controls the flow direction of the refrigerant and can selectively expand the refrigerant; and a second expansion valve that is located at a different position from the first expansion valve and controls the flow direction of the refrigerant and can selectively expand the refrigerant.

[0009] An expansion valve connection line connecting the first expansion valve and the second expansion valve is further provided.

[0010] The refrigerant passing through the second expansion valve can move to the first expansion valve via the expansion valve connection line, and the refrigerant expands in at least one of the first expansion valve and the second expansion valve depending on the air conditioning mode.

[0011] The refrigerant discharged from the compressor flows through the indoor heat exchanger and then to the directional change valve.

[0012] The first expansion valve and the second expansion valve include a plurality of communication ports, and at least two of the plurality of communication ports are configured to be changed to an inlet or an outlet of the refrigerant depending on the mode.

[0013] The first expansion valve is configured as a three-way valve connected to a refrigerant line between the outdoor heat exchanger and the second expansion valve, a chiller, and the second expansion valve, respectively, and the second expansion valve is configured as a three-way valve connected to the first expansion valve, the evaporator, and the outdoor heat exchanger, respectively.

[0014] The above directional valve is composed of a four-way valve connected to the refrigerant line between the evaporator, indoor heat exchanger, outdoor heat exchanger, chiller and compressor.

[0015] The first expansion valve expands the refrigerant that has passed through the outdoor heat exchanger and causes it to flow to the chiller, or expands the refrigerant that has passed through the second expansion valve and causes it to flow to the chiller, and the second expansion valve expands the refrigerant that has passed through the outdoor heat exchanger and causes it to flow to the evaporator, or expands the refrigerant that has passed through the evaporator and causes it to flow to the outdoor heat exchanger, or expands the refrigerant that has passed through the evaporator and causes it to flow to the first expansion valve.

[0016] A chiller refrigerant line is provided that branches from the refrigerant line between the outdoor heat exchanger and the second expansion valve and is connected to the chiller, and the first expansion valve is provided in the chiller refrigerant line.

[0017] In heating mode, the refrigerant first passes through the indoor heat exchanger and then passes through the evaporator, so that the air blown into the vehicle interior is heated through primary heat exchange with the evaporator and then through secondary heat exchange with the indoor heat exchanger.

[0018] A first connecting pipe that allows the refrigerant that has passed through the outdoor heat exchanger to flow to the first expansion valve or the second expansion valve; and a second connecting pipe that is formed on the downstream side of the directional switching valve in the refrigerant flow direction so that the refrigerant that has passed through the directional switching valve can flow to the compressor are further provided.

[0019] In cooling mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the directional valve to the outdoor heat exchanger, expands in the second expansion valve, passes through the evaporator, and circulates through the compressor.

[0020] In cooling and battery cooling mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the directional valve, passes through the outdoor heat exchanger, and some of it is expanded in the second expansion valve and then passes through the evaporator to circulate through the compressor, while the other part is expanded in the first expansion valve through the chiller refrigerant line and then passes through the chiller to circulate through the compressor.

[0021] In battery cooling mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger, the outdoor heat exchanger through the directional valve, and then through the chiller refrigerant line, where it is expanded in the first expansion valve and then circulates through the compressor through the chiller.

[0022] In the first heating mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the evaporator through the directional change valve, and is expanded in the second expansion valve. Some of the refrigerant passes through the chiller refrigerant line and the first expansion valve as is, passes through the chiller, and circulates through the compressor, while the other part passes through the outdoor heat exchanger and circulates through the compressor.

[0023] In the second heating mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the evaporator via the directional valve, is expanded in the second expansion valve, and then passes through the outdoor heat exchanger and circulates through the compressor.

[0024] In the third heating mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the evaporator through the directional valve, is expanded in the second expansion valve, and flows to the first expansion valve through the expansion valve connection line. After the refrigerant passes through the first expansion valve as is, it passes through the chiller and circulates through the compressor.

[0025] In the fourth heating mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the evaporator through the directional change valve, passes through the second expansion valve as is, flows to the first expansion valve through the expansion valve connection line, and after the refrigerant is expanded in the first expansion valve, passes through the chiller and circulates through the compressor.

[0026] In the first dehumidifying heating mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the directional change valve to the outdoor heat exchanger, expands in the second expansion valve, passes through the evaporator, and circulates through the compressor.

[0027] In the second dehumidifying heating mode, the refrigerant discharged from the compressor passes through the indoor heat exchanger and then the outdoor heat exchanger through the directional change valve, and then some of it is expanded in the second expansion valve and then passes through the evaporator and circulates through the compressor, and some of it is expanded in the first expansion valve through the chiller refrigerant line and then passes through the chiller and circulates through the compressor.

[0028] The vehicle thermal management system according to the present invention can implement various air conditioning modes with a simple configuration by optimizing the positions of one directional valve (a four-way valve) and two expansion valves (a three-way valve) and configuring the expansion means to selectively enable two-way expansion. This allows for a smaller overall air conditioning unit package.

[0029] In addition, by configuring the refrigerant valves with only three (one directional valve and two expansion valves), it is possible to drastically reduce manufacturing costs and increase price competitiveness by implementing various air conditioning modes such as cooling, heating, dehumidification, and battery cooling, as well as the functions of an integrated thermal management system for electric vehicles.

[0030] In addition, heating performance can be improved because the air is first heated through the evaporator and then heated a second time through the indoor heat exchanger. Since the refrigerant passing through the indoor heat exchanger is at a higher temperature than the refrigerant passing through the evaporator, the air can ultimately exchange heat with the indoor heat exchanger to maximize the heating effect. In addition, the condensed refrigerant is stored in the evaporator during heating mode, which can reduce the size of the system's accumulator. Meanwhile, the expansion valve connection line can maximize heating efficiency by selectively expanding the refrigerant through one of the two expansion valves during heating mode.

[0031] Figure 1 illustrates a conventional vehicle heat pump system.

[0032] FIG. 2 illustrates a vehicle thermal management system according to one embodiment of the present invention.

[0033] FIG. 3 illustrates a direction change valve of a vehicle thermal management system according to one embodiment of the present invention.

[0034] FIG. 4 illustrates a first expansion valve of a vehicle thermal management system according to one embodiment of the present invention.

[0035] FIG. 5 illustrates a second expansion valve of a vehicle thermal management system according to one embodiment of the present invention.

[0036] FIG. 6 is a drawing for explaining the operation mode of the first expansion valve and the second expansion valve according to one embodiment of the present invention.

[0037] FIG. 7 illustrates a cooling mode of a vehicle thermal management system according to one embodiment of the present invention.

[0038] FIG. 8 illustrates the cooling and battery cooling modes of a vehicle thermal management system according to one embodiment of the present invention.

[0039] FIG. 9 illustrates a battery cooling mode of a vehicle thermal management system according to an embodiment of the present invention.

[0040] FIG. 10 illustrates a first heating mode of a vehicle thermal management system according to an embodiment of the present invention.

[0041] FIG. 11 illustrates a second heating mode of a vehicle thermal management system according to an embodiment of the present invention.

[0042] FIG. 12 illustrates a third heating mode of a vehicle thermal management system according to an embodiment of the present invention.

[0043] FIG. 13 illustrates a fourth heating mode of a vehicle thermal management system according to an embodiment of the present invention.

[0044] FIG. 14 illustrates a first dehumidifying heating mode of a vehicle thermal management system according to an embodiment of the present invention.

[0045] FIG. 15 illustrates a second dehumidifying heating mode of a vehicle thermal management system according to one embodiment of the present invention.

[0046] The technical configuration of a vehicle thermal management system is described in detail according to the attached drawings as follows.

[0047] Referring to FIGS. 2 to 6, a vehicle thermal management system according to one embodiment of the present invention comprises a compressor (101) connected to a refrigerant line (191), an outdoor heat exchanger (102), an expansion means, an indoor heat exchanger (121), an evaporator (129), and a chiller (104).

[0048] In addition, a blower is provided on one side of the air conditioning case (120) to suck in internal or external air and discharge it into the vehicle interior. An evaporator (129) and an indoor heat exchanger (121) are sequentially provided in the air flow direction in the internal air passage of the air conditioning case (120). An electric heater (123) is provided downstream of the indoor heat exchanger (121) in the air flow direction inside the air conditioning case (120).

[0049] The electric heater (123) generates heat according to the application of power, and may be formed of a PTC heater, etc. The electric heater (123) functions as an auxiliary heat source, and is formed of a dual PTC so that it can be operated individually in the air passages partitioned on the left and right of the air conditioning case (120). A temp door (122) is provided between the evaporator (129) and the indoor heat exchanger (121) to control the discharge temperature of the air by controlling the amount of cold air and hot air.

[0050] The compressor (101) sucks in refrigerant, compresses it, and then discharges it as a high-temperature, high-pressure gas. The outdoor heat exchanger (102) is provided outside the air conditioning case (120) to exchange heat with the outside air, and can be installed in the front of the vehicle, etc. The indoor heat exchanger (121) is provided inside the air conditioning case (120) to exchange heat with the air discharged into the vehicle interior.

[0051] An accumulator (105) is provided upstream of the compressor (101) in the direction of refrigerant flow to separate the vapor and liquid of the refrigerant passing therethrough. In addition, a double pipe (103) is formed in the refrigerant pipe connecting the accumulator (105) and the compressor (101). The double pipe (103) exchanges heat between the refrigerant in the refrigerant line (191) connecting the outdoor heat exchanger (102) and the second expansion valve (300) and the refrigerant in the refrigerant line (191) connecting the accumulator (105) and the compressor (101).

[0052] The indoor heat exchanger (121) functions as a heating heat exchanger that heats the air. The expansion means expands the refrigerant. The evaporator (129) is provided upstream of the indoor heat exchanger (121) in the direction of air flow inside the air conditioning case (120). The evaporator (129) cools the air by exchanging heat with the air discharged into the vehicle interior. In other words, the evaporator (129) functions as a cooling heat exchanger that cools the air. The chiller (104) is a refrigerant-coolant heat exchanger that exchanges heat between the refrigerant and the coolant circulating in the vehicle's electrical components or batteries.

[0053] A vehicle thermal management system according to one embodiment of the present invention comprises a chiller refrigerant line (192) and an expansion valve connection line (193). Furthermore, the vehicle thermal management system further comprises a direction-changing valve (110). Furthermore, the expansion means comprises a first expansion valve (200) and a second expansion valve (300).

[0054] The chiller refrigerant line (192) branches from the refrigerant line between the outdoor heat exchanger (102) and the evaporator (129) and is connected to the chiller (104). The expansion valve connection line (193) connects the first expansion valve (200) and the second expansion valve (300).

[0055] The refrigerant passing through the second expansion valve (300) can move to the first expansion valve (200) via the expansion valve connection line (193). In this case, the refrigerant expands in at least one of the first expansion valve (200) and the second expansion valve (300) depending on the air conditioning mode. The expansion valve connection line (193) can maximize heating efficiency by selectively expanding the refrigerant in one of the first expansion valve (200) and the second expansion valve (300) in the heating mode. This will be described in detail later.

[0056] A vehicle thermal management system according to one embodiment of the present invention controls the flow of refrigerant discharged from a compressor (101) through a direction change valve (110), a first expansion valve (200), and a second expansion valve (300), thereby performing a series of air conditioning operations, such as cooling, heating, dehumidification, and battery cooling, of the vehicle interior.

[0057] The directional switching valve (110) controls the flow of the refrigerant discharged from the compressor (101) and passed through the indoor heat exchanger (121) so that it selectively flows to the outdoor heat exchanger (102) or the evaporator (129). The directional switching valve (110) is composed of a 4-way valve. The directional switching valve (110) is connected to the refrigerant lines between the evaporator (129), the indoor heat exchanger (121), the outdoor heat exchanger (102), the chiller (104), and the compressor (101). In this case, in all air conditioning modes, the refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121) and then flows to the directional switching valve (110).

[0058] The first expansion valve (200) is configured to control the flow direction of the refrigerant and to selectively expand the refrigerant. In addition, the first expansion valve (200) includes a plurality of communication ports, and at least two of the plurality of communication ports are configured to be changed to an inlet or an outlet of the refrigerant depending on the mode. That is, the first expansion valve (200) is configured as an electric expansion valve (EXV). In addition, the first expansion valve (200) is configured as a 3-way valve. The first expansion valve (200) is connected to the refrigerant line between the outdoor heat exchanger (102) and the second expansion valve (300), the chiller (104), and the second expansion valve (300), respectively.

[0059] The first expansion valve (200) is provided in the chiller refrigerant line (192). The first expansion valve (200) not only performs the function of expanding the refrigerant but also performs the function of changing the direction of the flow of the refrigerant, and can change the inlet and outlet during the expansion of the refrigerant. In other words, the first expansion valve (200) has three communication ports that selectively function as the inlet or outlet of the refrigerant depending on the air conditioning mode.

[0060] More specifically, the first expansion valve (200) can introduce refrigerant through a communication port connected to the refrigerant line between the outdoor heat exchanger (102) and the second expansion valve (300) among the three communication ports, expand the refrigerant, and then discharge the refrigerant through a communication port connected to the chiller (104). In addition, the first expansion valve (200) can introduce refrigerant through a communication port connected to the second expansion valve (300) among the three communication ports, expand the refrigerant, and then discharge the refrigerant through a communication port connected to the chiller (104).

[0061] In addition, the first expansion valve (200) may be configured to be in a fully closed state (Full Close) that completely blocks the flow of refrigerant. When fully closed, the first expansion valve (200) closes all three communication ports, so that the refrigerant does not flow to the first expansion valve (200). Meanwhile, the first expansion valve (200) may be in a one-way fully open state (Full Open), so that the refrigerant may pass through without being expanded.

[0062] The second expansion valve (300) is arranged at a different position from the first expansion valve (200) to control the flow direction of the refrigerant and to selectively expand the refrigerant. In addition, the second expansion valve (300) includes a plurality of communication ports, and at least two of the plurality of communication ports are configured to be changed to an inlet or an outlet of the refrigerant depending on the mode. That is, the second expansion valve (300) is formed as an electric expansion valve (EXV). In addition, the second expansion valve (300) is formed as a 3-way valve. The second expansion valve (300) is connected to the first expansion valve (200), the evaporator (129), and the outdoor heat exchanger (102), respectively.

[0063] The second expansion valve (300) has the same structure as the first expansion valve (200). That is, the second expansion valve (300) performs not only the expansion function of the refrigerant but also the direction-changing function of changing the flow of the refrigerant, and can change the inlet and outlet during the expansion of the refrigerant. That is, the second expansion valve (300) has three communication ports that selectively function as the inlet or outlet of the refrigerant depending on the air conditioning mode.

[0064] More specifically, the second expansion valve (300) can introduce refrigerant through a communication port connected to the outdoor heat exchanger (102) among the three communication ports, expand the refrigerant, and then discharge the refrigerant through a communication port connected to the evaporator (129). In addition, the second expansion valve (300) can introduce refrigerant through a communication port connected to the evaporator (129) among the three communication ports, expand the refrigerant, and then discharge the refrigerant through a communication port connected to the outdoor heat exchanger (102). In addition, the second expansion valve (300) can introduce refrigerant through a communication port connected to the evaporator (129) among the three communication ports, expand the refrigerant, and then discharge the refrigerant through a communication port connected to the first expansion valve (200).

[0065] In addition, the second expansion valve (300) can be configured to be in a fully closed state (Full Close) that completely blocks the flow of refrigerant. When fully closed, the second expansion valve (300) closes all three communication ports, so that the refrigerant does not flow to the second expansion valve (300). Meanwhile, the second expansion valve (300) can be in a one-way fully open state (Full Open), so that the refrigerant can pass through without expanding it.

[0066] The first expansion valve (200) expands the refrigerant that has passed through the outdoor heat exchanger (102) and causes it to flow to the chiller (104), or expands the refrigerant that has passed through the second expansion valve (300) and causes it to flow to the chiller (104). In addition, the second expansion valve (300) expands the refrigerant that has passed through the outdoor heat exchanger (102) and causes it to flow to the evaporator (129), or expands the refrigerant that has passed through the evaporator (129) and causes it to flow to the outdoor heat exchanger (102), or expands the refrigerant that has passed through the evaporator (129) and causes it to flow to the first expansion valve (200).

[0067] In heating mode, the high temperature and high pressure refrigerant discharged from the compressor (101) first passes through the indoor heat exchanger (121) and then passes through the evaporator (129) via the direction changing valve (110). Since the evaporator (129) is positioned upstream of the indoor heat exchanger (121) in the direction of air flow, the air blown into the vehicle interior is heated by first heat exchange with the evaporator (129) and then heated by second heat exchange with the indoor heat exchanger (121).

[0068] In this way, in the vehicle thermal management system according to one embodiment of the present invention, high temperature and high pressure refrigerant flows to the evaporator (129) in addition to the indoor heat exchanger (121) in the heating mode. Therefore, the air is first heated through the evaporator (129) and then heated a second time through the indoor heat exchanger (121), thereby improving heating performance. Since the refrigerant passing through the indoor heat exchanger (121) is at a higher temperature than the refrigerant passing through the evaporator (129), the air can ultimately exchange heat with the indoor heat exchanger (121) to maximize the heating effect. In addition, since the condensed refrigerant is stored in the evaporator (129) in the heating mode, the size of the accumulator (105) of the system can be reduced.

[0069] As illustrated in Fig. 6, the first expansion valve (200) and the second expansion valve (300) are not 3-way valves that simply change direction, nor are they throttle means that perform one-way expansion, but are three-way valves that can expand in multiple directions. That is, the three-way valve according to the present invention may be in a state where the second communication port is closed and the refrigerant flows into the first communication port, expands, and then flows into the third communication port (mode 1), or the second communication port is closed and the refrigerant flows into the third communication port, expands, and then flows into the first communication port (mode 1), or the second communication port is closed and the first communication port and the third communication port are in communication (mode 2), or the first communication port is closed and the second communication port and the third communication port are in communication (mode 3), or the first communication port is closed and the refrigerant flows into the second communication port, expands, and then flows into the third communication port (mode 4), or the first communication port is closed and the refrigerant flows into the third communication port, expands, and then flows into the second communication port (mode 4). In this way, the expansion inlet and outlet of the expansion valve (200, 300) are configured to be changeable.

[0070] Meanwhile, the vehicle thermal management system further comprises a first connecting pipe (161) and a second connecting pipe (162). The first connecting pipe (161) allows the refrigerant passing through the outdoor heat exchanger (102) to flow to the first expansion valve (200) or the second expansion valve (300). That is, the refrigerant flowing into the first connecting pipe (161) selectively flows to the first expansion valve (200) or to the second expansion valve (300) through the double pipe (103). The second connecting pipe (162) is formed downstream of the directional change valve in the refrigerant flow direction so that the refrigerant passing through the directional change valve (110) can flow to the compressor (101). That is, the refrigerant that has passed through the direction change valve (110) passes through the second connecting pipe (162), passes through the accumulator (105), and then flows to the compressor (101).

[0071] A vehicle thermal management system according to one embodiment of the present invention performs air conditioning, such as cooling, heating, dehumidification, and battery cooling, of the vehicle interior using an evaporator (129), an indoor heat exchanger (121), one directional switching valve (110), and two expansion valves (200, 300). That is, by optimizing the positions of one directional switching valve (4-way valve) and two expansion valves (3-way valve) and configuring the expansion valves (200, 300) to selectively enable bidirectional expansion, various air conditioning modes can be implemented with a simple configuration.

[0072] This allows for a reduction in the overall package of the air conditioning unit. Furthermore, by configuring only three refrigerant valves (one directional valve and two expansion valves), the system can achieve a variety of air conditioning modes, including cooling, heating, dehumidification, and battery cooling, as well as the integrated thermal management system of an electric vehicle, thereby dramatically reducing manufacturing costs and enhancing price competitiveness. Meanwhile, the expansion valve connection line (193) can selectively expand the refrigerant through one of the two expansion valves during heating mode, thereby maximizing heating efficiency.

[0073] Referring to Fig. 7, in cooling mode (Only A / C Mode), the high temperature and high pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121), the outdoor heat exchanger (102) through the directional change valve (110), exchanges heat with the outdoor air, and then is expanded in the second expansion valve (300). The refrigerant expanded in the second expansion valve (300) passes through the evaporator (129), the directional change valve (110), the accumulator (105), and circulates through the compressor (101). The refrigerant passing through the evaporator (129) exchanges heat with the air blown into the vehicle interior, thereby performing cooling. Since the communication port of the second expansion valve (300) is closed, the refrigerant does not flow to the chiller (104). In this case, the first expansion valve (200) can also be controlled to be fully closed (Full Close). The temp door (122) closes the hot air passage passing through the indoor heat exchanger (121) and the electric heater (123).

[0074] Referring to Fig. 8, in the cooling and battery cooling mode (A / C and Battery Cooling Mode), the high temperature and high pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121), passes through the directional change valve (110) and the outdoor heat exchanger (102), exchanges heat with the outdoor air, and then flows into the first connecting pipe (161), and some of it is expanded in the second expansion valve (300), passes through the evaporator (129), passes through the directional change valve (110), passes through the accumulator (105), and circulates through the compressor (101). The refrigerant passing through the evaporator (129) exchanges heat with the air blown into the vehicle interior to perform cooling.

[0075] Another portion of the refrigerant that has passed through the outdoor heat exchanger (102), exchanged heat with the outdoor air, and then flowed into the first connecting pipe (161) is expanded in the first expansion valve (200) through the chiller refrigerant line (192), and then passes through the chiller (104) to cool the cooling water circulating in the battery, and then passes through the accumulator (105) to circulate through the compressor (101). That is, the refrigerant that has passed through the directional change valve (110) flows into the second connecting pipe (162) and into the accumulator (105). In this case, both the first expansion valve (200) and the second expansion valve (300) perform one-way expansion, so that the expanded refrigerant is supplied to the chiller (104) and the evaporator (129), respectively. The temp door (122) closes the hot air passage passing through the indoor heat exchanger (121) and the electric heater (123).

[0076] As shown in FIGS. 7 and 8, when the refrigerant passing through the evaporator (129) flows to the accumulator (105) through the direction changing valve (110), the upper side and the left side of the direction changing valve (110) in the drawing are indicated in black shading.

[0077] Referring to Fig. 9, in the battery cooling mode (Only Battery Cooling Mode), the high temperature and high pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121), passes through the directional valve (110), passes through the outdoor heat exchanger (102), exchanges heat with the outdoor air, then expands in the first expansion valve (200) through the chiller refrigerant line (192), passes through the chiller (104), cools the cooling water circulating in the battery, and then passes through the accumulator (105) and circulates through the compressor (101). Since the communication port of the first expansion valve (200) is closed, the refrigerant does not flow into the expansion valve connection line (193). In this case, the second expansion valve (300) can also be controlled to be fully closed (Full Close). The temp door (122) closes the hot air passage passing through the indoor heat exchanger (121) and the electric heater (123).

[0078] Referring to Fig. 10, in the first heating mode (outside air and electric field waste heat absorption), the high temperature and high pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121) and the evaporator (129) through the direction change valve (110). The refrigerant passing through the indoor heat exchanger (121) and the refrigerant passing through the evaporator (129) exchange heat with the air blown into the vehicle interior, thereby performing heating.

[0079] The refrigerant that has passed through the evaporator (129) is expanded in the second expansion valve (300), and then some of it passes through the first expansion valve (200) via the chiller refrigerant line (192) and circulates through the chiller (104) and the accumulator (105) to the compressor (101). Another part of the refrigerant that has expanded in the second expansion valve (300) passes through the outdoor heat exchanger (102), the directional change valve (110), the accumulator (105), and circulates through the compressor (101). The refrigerant absorbs the waste heat of the entire system in the chiller (104) and the outside air in the outdoor heat exchanger (102).

[0080] Referring to Fig. 11, in the second heating mode (outside air heat absorption), the high temperature and high pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121) and the evaporator (129) through the direction change valve (110). The refrigerant passing through the indoor heat exchanger (121) and the refrigerant passing through the evaporator (129) exchange heat with the air blown into the vehicle interior, thereby performing heating.

[0081] The refrigerant passing through the evaporator (129) expands in the second expansion valve (300), then passes through the outdoor heat exchanger (102), the directional change valve (110), the accumulator (105), and circulates through the compressor (101). The refrigerant absorbs heat from the outside air in the outdoor heat exchanger (102). Since the communication port of the second expansion valve (300) is closed, the refrigerant does not flow to the chiller (104). In this case, the first expansion valve (200) can also be controlled to be fully closed (Full Close). The temp door (122) opens the warm air passage passing through the indoor heat exchanger (121) and the electric heater (123). This mode can be used in environments such as when the waste heat of the entire vehicle is not sufficient at the beginning of the vehicle startup.

[0082] Referring to Fig. 12, in the third heating mode (full-range waste heat absorption, second expansion valve expansion), the high-temperature and high-pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121) and the evaporator (129) through the direction change valve (110). The refrigerant passing through the indoor heat exchanger (121) and the refrigerant passing through the evaporator (129) exchange heat with the air blown into the vehicle interior, thereby performing heating.

[0083] The refrigerant passing through the evaporator (129) expands in the second expansion valve (300) and then flows to the first expansion valve (200) through the expansion valve connection line (193). The refrigerant passes through the first expansion valve (200) as is, then passes through the chiller (104) and the accumulator (105) and circulates through the compressor (101). In this case, the first expansion valve (200) passes the refrigerant through without expanding it, and the second expansion valve (300) performs one-way expansion so that the expanded refrigerant is supplied to the first expansion valve (200). The temp door (122) opens the hot air passage passing through the indoor heat exchanger (121) and the electric heater (123).

[0084] In this way, the inlet and outlet of the refrigerant are changed in both directions, and bidirectional expansion is possible. Through the configuration of the expansion valve connection line (193) connecting the first expansion valve (200) and the second expansion valve (300), the refrigerant that has passed through the indoor heat exchanger (121) can be expanded in the second expansion valve (300) rather than the first expansion valve (200).

[0085] Referring to Fig. 13, in the fourth heating mode (full-range waste heat absorption, first expansion valve expansion), the high-temperature and high-pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121) and the evaporator (129) through the direction change valve (110). The refrigerant passing through the indoor heat exchanger (121) and the refrigerant passing through the evaporator (129) exchange heat with the air blown into the vehicle interior, thereby performing heating.

[0086] The refrigerant that has passed through the evaporator (129) passes through the second expansion valve (300) as is and flows to the first expansion valve (200) through the expansion valve connection line (193). After the refrigerant is expanded in the first expansion valve (200), it passes through the chiller (104) and the accumulator (105) and circulates through the compressor (101). In this case, the first expansion valve (200) performs one-way expansion so that the expanded refrigerant is supplied to the chiller (104), and the second expansion valve (300) passes the refrigerant as is without expanding it. The temp door (122) opens the hot air passage that passes through the indoor heat exchanger (121) and the electric heater (123).

[0087] The fourth heating mode, which expands in the first expansion valve (200), can further maximize heating efficiency compared to the third heating mode structure, which expands in the second expansion valve (300). This is because, in addition to the indoor heat exchanger (121), more high-temperature refrigerant exists in the expansion valve connection line (193) between the first expansion valve (200) and the second expansion valve (300), so that when the performance is the same, the pressure of the overall heat management system is lowered and the power consumption of the compressor (101) is lowered, so the structure, which expands in the first expansion valve (200), has better heating efficiency.

[0088] As shown in FIGS. 10 to 13, when the refrigerant passing through the indoor heat exchanger (121) flows to the evaporator (129) through the direction changing valve (110), the upper side and the right side of the direction changing valve (110) in the drawing are indicated with black shading.

[0089] Referring to Fig. 14, in the first dehumidification and heating mode, the high temperature and high pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121), passes through the directional change valve (110), passes through the outdoor heat exchanger (102), exchanges heat with the outdoor air, and then expands in the second expansion valve (300), passes through the evaporator (129), passes through the directional change valve (110), passes through the accumulator (105), and circulates through the compressor (101).

[0090] The refrigerant passing through the evaporator (129) exchanges heat with the air blown into the vehicle interior to perform dehumidification. In addition, the refrigerant passing through the indoor heat exchanger (121) exchanges heat with the air blown into the vehicle interior to perform heating. Since the communication port of the second expansion valve (300) is closed, the refrigerant does not flow to the chiller (104). In this case, the first expansion valve (200) can also be controlled to be fully closed (Full Close). The temp door (122) opens the hot air passage passing through the indoor heat exchanger (121) and the electric heater (123).

[0091] Referring to FIG. 15, in the second dehumidification and heating mode, the high temperature and high pressure refrigerant discharged from the compressor (101) passes through the indoor heat exchanger (121), passes through the directional change valve (110), passes through the outdoor heat exchanger (102), exchanges heat with the outdoor air, and then some of it is expanded in the second expansion valve (300), passes through the evaporator (129), passes through the directional change valve (110), passes through the accumulator (105), and circulates through the compressor (101).

[0092] Another portion of the refrigerant that has passed through the outdoor heat exchanger (102) is expanded in the first expansion valve (200) through the chiller refrigerant line (192), then passes through the chiller (104) to cool the coolant circulating in the battery, and then passes through the accumulator (105) to circulate through the compressor (101). The refrigerant that has passed through the evaporator (129) exchanges heat with the air blown into the vehicle interior to perform dehumidification. In addition, the refrigerant that has passed through the indoor heat exchanger (121) exchanges heat with the air blown into the vehicle interior to perform heating. The temp door (122) opens the hot air passage that passes through the indoor heat exchanger (121) and the electric heater (123).

[0093] As shown in FIGS. 14 and 15, when the refrigerant passing through the evaporator (129) flows to the accumulator (105) through the direction changing valve (110), the upper side and the left side of the direction changing valve (110) in the drawing are indicated in black shading.

[0094]

[0095] While the vehicle thermal management system according to the present invention has been described with reference to the embodiments illustrated in the drawings, these are merely exemplary, and anyone skilled in the art will understand that various modifications and equivalent alternative embodiments are possible. Therefore, the true scope of technical protection should be determined by the technical spirit of the appended claims.

Claims

1. A compressor that compresses and discharges refrigerant; An indoor heat exchanger installed inside the air conditioning case that heats the air by exchanging heat with the air discharged into the vehicle interior; An outdoor heat exchanger installed outside the air conditioning case to exchange heat with the outside air; An evaporator installed upstream of the indoor heat exchanger in the direction of air flow inside the air conditioning case to cool the air by exchanging heat with the air discharged into the vehicle interior; A chiller that exchanges heat between refrigerant and cooling water; A directional valve that controls the flow of refrigerant passing through the indoor heat exchanger to flow to the outdoor heat exchanger or evaporator; A first expansion valve capable of controlling the flow direction of the refrigerant and selectively expanding the refrigerant; and A vehicle thermal management system comprising a second expansion valve positioned at a different location from the first expansion valve to control the flow direction of the refrigerant and selectively expand the refrigerant.

2. In paragraph 1, A vehicle thermal management system further comprising an expansion valve connection line connecting the first expansion valve and the second expansion valve.

3. In paragraph 2, A vehicle thermal management system characterized in that the refrigerant passing through the second expansion valve can move to the first expansion valve through the expansion valve connection line, and the refrigerant expands in at least one of the first expansion valve and the second expansion valve depending on the air conditioning mode.

4. In paragraph 2, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor flows through the indoor heat exchanger and then to the directional change valve.

5. In paragraph 2, A vehicle thermal management system, characterized in that the first expansion valve and the second expansion valve include a plurality of communication ports, and at least two of the plurality of communication ports are configured to be changed into an inlet or an outlet of a refrigerant depending on the mode.

6. In paragraph 2, The above first expansion valve is composed of a three-way valve connected to the refrigerant line between the outdoor heat exchanger and the second expansion valve, the chiller, and the second expansion valve, respectively. A vehicle thermal management system characterized in that the second expansion valve is composed of a three-way valve each connected to the first expansion valve, the evaporator, and the outdoor heat exchanger.

7. In paragraph 6, The above directional valve is a vehicle thermal management system consisting of a four-way valve each connected to a refrigerant line between an evaporator, an indoor heat exchanger, an outdoor heat exchanger, a chiller, and a compressor.

8. In paragraph 6, The above first expansion valve is configured to expand the refrigerant that has passed through the outdoor heat exchanger and flow to the chiller, or to expand the refrigerant that has passed through the second expansion valve and flow to the chiller. A vehicle thermal management system in which the second expansion valve expands the refrigerant that has passed through the outdoor heat exchanger and causes it to flow to the evaporator, or expands the refrigerant that has passed through the evaporator and causes it to flow to the outdoor heat exchanger, or expands the refrigerant that has passed through the evaporator and causes it to flow to the first expansion valve.

9. In paragraph 7, A chiller refrigerant line is provided that branches from the refrigerant line between the above outdoor heat exchanger and the second expansion valve and is connected to the chiller. A vehicle thermal management system, characterized in that the first expansion valve is provided in the chiller refrigerant line.

10. In paragraph 7, A vehicle heat management system in which, in heating mode, the refrigerant first passes through the indoor heat exchanger and then passes through the evaporator, so that the air blown into the vehicle interior is heated by first heat exchange with the evaporator and then second heat exchange with the indoor heat exchanger.

11. In paragraph 9, A first connecting pipe that allows the refrigerant passing through the outdoor heat exchanger to flow to the first expansion valve or the second expansion valve; and A vehicle thermal management system further comprising a second connecting pipe formed on the downstream side of the directional valve in the direction of refrigerant flow so that refrigerant passing through the directional valve can flow to the compressor.

12. In paragraph 9, In cooling mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through an indoor heat exchanger, passes through a directional valve to an outdoor heat exchanger, is expanded in a second expansion valve, passes through an evaporator, and circulates through the compressor.

13. In paragraph 9, In cooling and battery cooling mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the outdoor heat exchanger through the directional valve, and then some of it is expanded in the second expansion valve and then passes through the evaporator and circulates through the compressor, and the other part is expanded in the first expansion valve through the chiller refrigerant line and then passes through the chiller and circulates through the compressor.

14. In paragraph 9, In battery cooling mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the directional valve, passes through the outdoor heat exchanger, is expanded in the first expansion valve through the chiller refrigerant line, and then passes through the chiller and circulates through the compressor.

15. In paragraph 9, In the first heating mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through an indoor heat exchanger, passes through an evaporator through a directional valve, and is expanded in a second expansion valve, and then some of the refrigerant passes through a chiller refrigerant line through the first expansion valve as is and circulates through the chiller and the compressor, and the other part passes through an outdoor heat exchanger and circulates through the compressor.

16. In paragraph 9, In the second heating mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through an indoor heat exchanger, passes through an evaporator via a directional valve, is expanded in a second expansion valve, passes through an outdoor heat exchanger, and circulates through the compressor.

17. In paragraph 9, In the third heating mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through an indoor heat exchanger, passes through an evaporator through a directional valve, is expanded in a second expansion valve, flows through an expansion valve connection line to a first expansion valve, and then passes through a chiller and circulates through a compressor as is from the first expansion valve.

18. In paragraph 9, In the 4th heating mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through an indoor heat exchanger, passes through an evaporator through a directional valve, passes through a second expansion valve as is, flows to a first expansion valve through an expansion valve connection line, and after the refrigerant is expanded in the first expansion valve, passes through a chiller and circulates through the compressor.

19. In paragraph 9, In the first dehumidifying heating mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through an indoor heat exchanger, passes through a directional valve to an outdoor heat exchanger, is expanded in a second expansion valve, passes through an evaporator, and circulates through the compressor.

20. In paragraph 9, In the second dehumidifying heating mode, A vehicle thermal management system characterized in that the refrigerant discharged from the compressor passes through the indoor heat exchanger, passes through the outdoor heat exchanger through the directional valve, and then some of it is expanded in the second expansion valve and then passes through the evaporator and circulates through the compressor, and some of it is expanded in the first expansion valve through the chiller refrigerant line and then passes through the chiller and circulates through the compressor.

Images