KR101663406B1 - Heat pump and hvac system architecture for electric vehicles - Google Patents

Abstract

The HVAC system of an electric vehicle includes a housing having an inlet for receiving the flow of air passing therethrough and an air outlet in fluid communication with the passenger compartment of the electric vehicle. The HVAC system further includes a first heat exchanger disposed in the housing downstream from the first heat exchanger in relation to the direction of flow of air through the housing and a second heat exchanger disposed within the housing. The primary flow path receives the flow of coolant therethrough and is in fluid communication with the first heat exchanger. The secondary flow path is in fluid communication with the primary flow path and in heat exchange communication and in fluid communication with the secondary heat exchanger.

Description

[0001] HEAT PUMP AND HVAC SYSTEM ARCHITECTURE FOR ELECTRIC VEHICLES [0002]

The present invention relates to a heating, ventilating and air conditioning (HVAC) system for a vehicle, and more particularly to a combined refrigeration plant of an HVAC system for heating, cooling and dehumidifying air for a passenger compartment and a heat exchanger And an auxiliary heater for use in dehumidifying air for the passenger compartment.

As is well known, a vehicle typically includes a climate control system that maintains the temperature in the passenger compartment of the vehicle at a comfortable level by providing heating, cooling and ventilation. The comfort in the passenger compartment is maintained by an integrated mechanism known in the art as a heating, ventilation and air conditioning (HVAC) system. The HVAC system performs conditioning of the air flowing through the HVAC system and distributes the conditioned air throughout the passenger compartment.

Typically, during operation, the compressors of the HVAC system provide the flow of fluid having the desired temperature to the evaporator disposed within the HVAC system to condition the air. The compressor is typically driven by a fuel powered engine of the vehicle, such as an internal combustion engine. A typical HVAC system is known to heat the passenger compartment during the heating mode, cool during the cooling mode, and dehumidify the passenger compartment during the demist mode. During the demister mode, if the ambient temperature is higher than 20 ° C, the air flowing through the HVAC to the passenger compartment is first cooled and dehumidified sufficiently. The cooled air is then reheated to provide the desired comfort to the passenger compartment. A typical HVAC system uses waste heat from an internal combustion engine to provide heating during the heating mode and reheat the cooled air by providing heat during the demister mode.

However, as the cost of conventional fuels rises, vehicles with improved fuel economy than fuel-powered engines and other vehicles are rapidly gaining popularity. An example of a vehicle with improved fuel economy is an electric vehicle. An electric vehicle includes an electric motor that is powered by an energy source, such as a battery. However, the electric vehicle does not provide the amount of waste heat required to heat the air flowing into the passenger compartment through the HVAC system to the desired temperature during the heating mode or the demister mode.

Accordingly, the HVAC system for an electric vehicle is known to include a combined refrigeration facility and heat pump operation for heating, cooling and dehumidifying the passenger compartment of the vehicle. However, these systems can not provide reheating during the demister mode due to the absence of waste heat from the fuel-powered engine. To overcome these deficiencies, additional electrical elements such as PTC heaters (positive temperature coefficient heaters) are used for reheating. However, the electrical component uses the energy drawn from the electrical system, thereby degrading the overall efficiency of the electric vehicle.

Thus, other systems for reheating air during the demister mode may be employed. For example, U.S. Patent No. 2007/0283703 discloses an air conditioning unit for combined refrigeration and heat pump operation. The air-conditioning unit includes a primary flow passage and a secondary flow passage. The primary flow path includes a gas cooler and an evaporator, and the secondary flow path includes a gas cooler. The secondary flow path is used to heat the dehumidified air during operation of the heat pump. Although the above-described air-conditioning unit is suitable for providing a combined refrigeration facility and heat pump operation for heating, cooling and dehumidification, there is an inefficient problem.

Additionally, the HVAC system typically employs a housing having an air flow conduit to carry air from the air supply to the passenger compartment. The air flow conduit of the HVAC system may be divided into two or more passages. At least one of these passages is provided with a heater core for heating the air. The housing may include a blend door to allow air to flow through one or more passageways to heat the air, cool the air, or dehumidify the air. An HVAC system including a housing with a bladed door, although suitable for heating, cooling and dehumidification, can occupy a significant volume of vehicle space, increase noise and vibration, and result in additional complexity. An example of a HVAC system including a housing with a blended door is described in U.S. Patent Application Publication No. 2013/0105126.

Furthermore, the electric vehicle is further restricted in that the battery of the electric vehicle must be cooled to maintain the optimum efficiency of the electric vehicle. In an electric vehicle, propulsion is provided by a battery. Energy is stored in the battery to drive the electric battery. When energy is stored in the battery assembly or discharged from the battery assembly, heat is generated in the battery. The heat minimizes the performance efficiency of the battery, which in turn minimizes the performance efficiency of the electric vehicle.

While known HVAC systems perform adequately, it is desirable to provide a method of operating an HVAC system for an electric vehicle and an HVAC system for an electric vehicle that maximizes the effectiveness and efficiency of an HVAC system and an electric vehicle while maintaining cost, weight, and package space requirements desirable.

It is an object of the present invention to provide a combined refrigeration plant for HVAC systems for heating, ventilating and air conditioning (HVAC) systems of vehicles, in particular for passenger compartments for heating, cooling and dehumidifying air, And an auxiliary heater for use in dehumidifying the air against the air.

According to one embodiment of the invention, the HVAC system includes a housing having an inlet for receiving the flow of air and an air outlet in fluid communication with the passenger compartment of the vehicle. The first heat exchanger is disposed within the housing and is configured to receive a flow of air through the housing. The second heat exchanger is disposed in the housing downstream from the first heat exchanger with respect to the direction of flow of air through the housing. The second heat exchanger is configured to receive the flow of air. The primary flow path receives the flow of coolant and is in fluid communication with the first heat exchanger. The primary flow path includes a compressor, a third heat exchanger, at least one expansion valve, and a plurality of valves. Each valve cooperates with one another to selectively carry the flow of coolant through the first heat exchanger in a first direction and a second direction. The secondary flow path performs either fluid communication and heat exchange communication with a portion of the primary flow path between the third heat exchanger and the at least one expansion valve. The secondary flow path is in fluid communication with the second heat exchanger.

According to another embodiment of the present invention, a method of operating an HVAC system of an electric vehicle is disclosed. The method includes providing a housing having an inlet for receiving the flow of air and an outlet in fluid communication with the passenger compartment of the vehicle. The method includes placing a first heat exchanger in the housing downstream from the first heat exchanger and a second heat exchanger in the housing in relation to the direction of air flow. Additionally, the method includes providing a primary flow path that is configured to receive the flow of penetrating coolant and to operate in at least a cooling mode, a demister mode, and a heating mode. The primary flow path includes a compressor, a third heat exchanger, and at least one expansion valve in fluid communication with the first heat exchanger, respectively.

The method includes directing a flow of coolant through a first heat exchanger in a first direction during a cooling mode and a demister mode and in a second direction during a heating mode and communicating the flow of coolant in fluid communication with the third heat exchanger And providing a secondary flow path for performing one of fluid communication and heat exchange communication with a part of the primary flow path between the at least one expansion valve.

According to a further embodiment of the present invention, a method of operating an HVAC system of an electric vehicle is disclosed. The method includes providing a housing having an inlet for receiving the flow of air and an outlet in fluid communication with the passenger compartment of the vehicle. The method includes placing a first heat exchanger in the housing downstream from the first heat exchanger and a second heat exchanger in the housing in relation to the direction of air flow. Additionally, the method includes providing a primary flow path that is configured to receive the flow of coolant and to operate in at least a cooling mode, a demister mode, and a heating mode. The primary flow path includes a compressor, a third heat exchanger, and at least one expansion valve in fluid communication with the first heat exchanger, respectively. The method includes directing a flow of coolant through a first heat exchanger in a first direction during a cooling mode and a demister mode and in a second direction during a heating mode and communicating the flow of coolant in fluid communication with the third heat exchanger And providing a secondary flow path for performing one of fluid communication and heat exchange communication with a part of the primary flow path between the at least one expansion valve. The method further comprises the step of guiding one of the refrigerant flow and the refrigerant flow through the second heat exchanger during the demister mode.

In accordance with the present invention, there is provided a combined heating and ventilation (HVAC) system for a vehicle, in particular a combined refrigeration plant of an HVAC system for heating, cooling and dehumidifying air for a passenger compartment, There is provided an HVAC system of an electric vehicle having an auxiliary heater for use in dehumidifying air.

Other objects and advantages of the present invention will become apparent to those skilled in the art by reading the following detailed description of a preferred embodiment of the present invention when taken in light of the accompanying drawings.
1 is a schematic flow diagram of an HVAC system in accordance with an embodiment of the present invention, wherein the HVAC system is configured to operate in a cooling mode, a dehumidification mode, and a heating mode.
Figure 2 is a schematic flow diagram of the HVAC system of Figure 1, illustrating an HVAC system operating in a cooling mode.
Figure 3 is a schematic flow diagram of the HVAC system of Figure 1, illustrating an HVAC system operating in a demister mode.
Figure 4 is a schematic flow diagram of the HVAC system of Figure 1, illustrating an HVAC system operating in a heating mode.
5 is a schematic flow diagram of an HVAC system in accordance with another embodiment of the present invention, wherein the HVAC system is configured to operate in a cooling mode, a dehumidification mode, and a heating mode.
6 is a schematic flow diagram of the HVAC system of FIG. 5, illustrating an HVAC system operating in a cooling mode.
Figure 7 is a schematic flow diagram of the HVAC system of Figure 5, illustrating an HVAC system operating in a demister mode.
Figure 8 is a schematic flow diagram of the HVAC system of Figure 5, illustrating an HVAC system operating in a heating mode.

The following detailed description and accompanying drawings illustrate and present various embodiments of the invention. The following detailed description and drawings serve to enable those skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any way. With regard to the disclosed method, the steps presented are illustrative in nature and accordingly the order of these steps is not essential or important. Except as otherwise expressly stated, all amounts expressed in numerical values in this specification should be understood to be modified by the word "about" in describing the broadest scope of the description.

1 illustrates a heating, ventilation, and air conditioning (HVAC) system 10 in accordance with an embodiment of the present invention. The HVAC system 10 provides heating, ventilation, and air conditioning for the passenger compartment of an ordinary electric vehicle (not shown). The electric vehicle includes a battery 11 for supplying power to an electric motor (not shown) of the electric vehicle.

The HVAC system 10 includes a hollow casing or housing 12 for carrying air. The housing (12) includes an air inlet (18) and an air outlet (19). The air inlet 18 is in fluid communication with a supply of air (not shown). For example, the supply of air can be made from outside the vehicle, recirculated from the passenger compartment of the vehicle, or a mixture of the two. The air outlet 19 is in fluid communication with the passenger compartment. The housing 12 is adapted to receive a blower (not shown) disposed adjacent to the air inlet 18 and to carry air through the housing 12. It will be appreciated that other components for conditioning the air may also be disposed upstream or downstream of the air inlet 18 with respect to the direction of the flow of air through the housing 12 as needed. For example, the filter may be disposed upstream or downstream of the air inlet 18 with respect to the direction of flow of air through the housing 12.

The housing 12 is configured to receive the first heat exchanger 14 and the second heat exchanger 16. Each of the first heat exchanger (14) and the second heat exchanger (16) regulates the air flowing through the housing (12). The second heat exchanger 16 is disposed in the housing 12 downstream from the first heat exchanger 14 in relation to the direction of flow of air through the housing 12. [ The first heat exchanger 14 may be any conventional type of heat exchanger configured to provide heat exchange between fluid and air flowing through the housing 12. The first heat exchanger 14 is also configured to operate both as an evaporator for cooling the air flowing through the housing 12 and as a heater core or secondary condenser for heating the air flowing through the housing 12 . The second heat exchanger 16 is a heat exchanger configured to provide heat exchange between the fluid and the air flowing through the housing 12.

In the embodiment shown in FIG. 1, for example, the second heat exchanger 16 is separate from the first heat exchanger 14. However, the second heat exchanger 16 may be integrally formed with the first heat exchanger 14, may be coupled to the first heat exchanger 14, or may be adjacent to the first heat exchanger 14 have. Moreover, in certain embodiments, the second heat exchanger 16 has a smaller dimension than the first heat exchanger 14. [ For example, the second heat exchanger 16 may have a thickness that is equal to 40 percent of the thickness of the first heat exchanger 14. However, it will be appreciated that the second heat exchanger 16 may have any thickness or other dimensions as desired based on vehicle performance and package requirements, as desired.

The HVAC system 10 further includes a primary flow path 20 in fluid communication with the first heat exchanger 14 and a secondary flow path 30 in fluid communication with the second heat exchanger 16. [ The primary flow path 20 is shown in solid lines in FIG. 1 and the secondary flow path 30 is shown in dotted lines. The primary flow path 20 is configured as a reversible heat pump. The primary flow path 20 is connected to the first heat exchanger 14 via a first heat exchanger 14 to cool the air flowing through the first heat exchanger 14 or to heat air flowing through the first heat exchanger 14. [ Lt; / RTI > The coolant may be any of the cooling, such as for example R134a, and HFO-1234yf, AC-5, AC-6, or CO _2. The primary flow path 20 further includes a compressor 22, a third heat exchanger 24, a fourth heat exchanger 26, a first expansion valve 32 and a second expansion valve 33. The primary flow path 20 is connected to the primary heat exchanger 20 via its various components (the first heat exchanger 14, the compressor 22, the third heat exchanger 24, the fourth heat exchanger 26, the first expansion valve 32, 2 expansion valve (s) 34), as will be appreciated by those skilled in the art.

The compressor 22 is in fluid communication with the first heat exchanger 14 and the third heat exchanger 24 and is disposed between the first heat exchanger and the second heat exchanger. The third heat exchanger 24 is in fluid communication with the compressor 22 and the fourth heat exchanger 26 and is disposed between the compressor and the fourth heat exchanger. The third heat exchanger 24 receives the flow of air from the air supply. For example, the air supply may be provided from outside the vehicle. In a particular embodiment, a fan 28 is disposed adjacent to the third heat exchanger 24 to carry air through the third heat exchanger 24. The third heat exchanger 24 may be any conventional type of heat exchanger configured to provide heat exchange between the passing air and the coolant flowing through the primary flow path 20.

The fourth heat exchanger 26 is disposed adjacent to the third heat exchanger 24 between the third heat exchanger 24 and the first heat exchanger 14. The fourth heat exchanger 26 is configured to provide heat exchange between the fluid and the coolant flowing through the primary flow path 20. Each of the first expansion valve 32 and the second expansion valve 33 is disposed between the fourth heat exchanger 26 and the first heat exchanger 14.

The primary flow path 20 is configured to carry the coolant through the first heat exchanger 14 in both the first direction and the second direction. The primary flow path 20 includes a main path 34 for conveying the coolant in the first direction through the primary flow path 20 and consequently through the first heat exchanger 14. The primary flow path 20 includes a first heat exchanger 14, a compressor 22, a third heat exchanger 24, a fourth heat exchanger 26 and a first expansion valve 32.

The first valve 42 is disposed in the main path 34 between the first heat exchanger 14 and the compressor 22. The flow of coolant between the first heat exchanger 14 and the compressor 22 is controlled by the first valve 42. A second valve (44) is disposed in the main path (34) between the compressor (22) and the third heat exchanger (24). The flow of coolant between the compressor 22 and the third heat exchanger 24 is controlled by the second valve 44. The third valve 46 is disposed in the main path 34 between the fourth heat exchanger 26 and the first expansion valve 32. The flow of coolant between the fourth heat exchanger (26) and the first expansion valve (32) is controlled by the third valve (46). It will be appreciated that more or fewer valves may be used as needed to control the flow of coolant through the main path 34 of the primary flow path 20.

The primary flow path 20 further includes a first bypass circuit 36, a second bypass circuit 38 and a third bypass circuit 40. These bypass lines 36,38 and 40 are configured to carry the flow of coolant through the primary flow path 20 and consequently in the second direction through the first heat exchanger 14. [ The first bypass 36 is connected to the node A of the main path 34 of the primary flow path 20 between the compressor 22 and the second valve 44, 1 valve 42 between the nodes B of the main path 34 of the primary flow path 20 to carry the coolant. The second bypass circuit 38 is connected to the node C of the main path 34 of the primary flow path 20 between the second valve 44 and the third heat exchanger 24, And between the node D of the main path 34 of the primary flow path 20 between the compressor 22 and the compressor 22 to carry the coolant. The third bypass circuit 40 is connected to the node E of the main path 34 of the primary flow path 20 between the third valve 46 and the fourth heat exchanger 26 and the first expansion valve 32 And the node F of the main path 34 of the primary flow path 20 between the first heat exchanger 14 and the first heat exchanger 14 to deliver the coolant. It will be appreciated that more bypass or less bypass may be used as needed for transport of the coolant through the primary flow path 20.

The first bypass (36) includes a fourth valve (48) disposed therein. The flow of coolant through the first bypass 36 is controlled by the fourth valve 48. A fifth valve 50 is disposed in the second bypass 38 to control the flow of coolant through the second bypass 38. A sixth valve 52 is disposed in the third bypass 40 to control the flow of coolant through the third bypass 40. It will be appreciated that more or fewer valves may be disposed in each of the bypass lines 36, 38, 40 of the primary flow path 20, if desired.

The third bypass 40 further includes a second expansion valve 33 located between the sixth valve 52 and the first heat exchanger 14. The first expansion valve 32 is configured to receive the flow of coolant carried through the primary flow path 20 in a first direction. The second expansion valve (33) is configured to receive a flow of coolant carried through the primary flow path (20) in a second direction.

The secondary flow path 30 carries the refrigerant passing through it. The refrigerant may be any refrigerant such as, for example, glycol refrigerant. However, other refrigerants such as water or a coolant may be used as needed. The secondary flow path 30 is in fluid communication with the second heat exchanger 16 and the fourth heat exchanger 26. It will be appreciated that the secondary flow path 30 includes one or more conduits that provide fluid communication between its various components (the second heat exchanger 16 and the fourth heat exchanger 26).

The secondary passage 30 includes a main passage 54 and a first bypass passage 56. A flow control device 58, such as a pump, is disposed in the secondary flow path 30 to allow refrigerant to circulate therethrough. The flow control device 58 is disposed in the main path 54 of the secondary flow path 30 between the second heat exchanger 16 and the fourth heat exchanger 26. However, the flow control device 58 may be disposed in the secondary flow path 30 at any position as required. The first valve 60 is disposed in the main path 54 of the secondary flow path 30 to control the flow of the coolant through the main path 54 of the secondary flow path 30. It will be appreciated that more or fewer valves may be disposed in the main path 54 as needed.

The first bypass path (56) of the secondary flow path (30) communicates with the battery (11) of the electric vehicle in heat exchange communication. The first bypass 56 is connected to the node G of the main path 54 of the secondary flow path 30 between the flow control device 58 and the fourth heat exchanger 26 and to the second heat exchanger 16 Between the first heat exchanger 26 and the fourth heat exchanger 26 and the node H of the main path 54 of the secondary flow path 30 to carry the flow of coolant. The first bypass path 56 of the secondary flow path 30 includes the second valve 64 to control the flow of the refrigerant through the first bypass path 56 of the secondary flow path 30. It will be appreciated that more or fewer valves may be disposed in the first bypass 56 as desired.

In a particular embodiment, the secondary flow path 30 may include a second bypass 68, a third valve 70, a fourth valve 72, and a fifth valve 74, Respectively. The second bypass path 68 of the secondary flow path 30 is connected to the node I of the main path 54 of the secondary flow path 30 between the flow control device 58 and the fourth heat exchanger 26 And between the second heat exchanger 16 and the flow control device 58 and the node J of the main path 54 of the secondary flow path 30 to carry the refrigerant.

The third valve 70 of the secondary flow path 30 is connected to the main path 54 of the secondary flow path 30 between the first valve 60 and the second heat exchanger 16 of the secondary flow path 30, As shown in FIG. The third valve 70 controls the flow of the refrigerant passing through a part of the main path 54 of the secondary flow path 30. The fourth valve 72 of the secondary passage 30 may be disposed between the node I and the node G of the main passage 54 of the secondary passage 30. [ The fourth valve 72 controls the flow of the refrigerant passing through a part of the main path 54 of the second flow path. The fifth valve 74 of the secondary flow path 30 may be disposed in the second bypass 68 to control the flow of refrigerant therethrough. It will be appreciated that more or fewer valves may be disposed in the second bypass path 68 and the main path 54 of the secondary flow path 30 as needed. In addition, more bypass or less bypass may be included in the secondary flow path 30 as needed.

During operation, the HVAC system 10 conditions the air flowing from the air source into the passenger compartment. The direction of the flow of air passing through the housing 12 is indicated by an arrow. The HVAC system 10 can be operated to cool the passenger compartment during the cooling mode and can be operated to heat the passenger compartment during the heating mode and can be operated to remove moisture from the passenger compartment during the demister mode.

2, a cooling mode of the HVAC system 10 is shown. In the cooling mode, the coolant is conveyed through the primary flow path 20 in the first direction. The first direction of the flow of coolant through the primary flow path 20 is indicated by the arrowhead. The first valve 42 of the primary flow passage 20, the second valve 44 of the primary flow passage 20 and the third valve 46 of the primary flow passage 20 are opened at the open position, (34) of the main body (20). The fourth valve 48 of the primary flow path 20, the fifth valve 50 of the primary flow path 20 and the sixth valve 52 of the primary flow path 20 are connected to the bypass path of the primary flow path 20, (36, 38, 40). ≪ / RTI >

Continuing to refer to FIG. 2, the coolant is compressed in the compressor 22 and then conveyed to the third heat exchanger 24. The third heat exchanger 24 transfers heat from the coolant to the air carried by the fan 28. The heated air passing through the third heat exchanger 24 is then carried to the atmosphere. The coolant is then conveyed through the fourth heat exchanger 26 to the first expansion valve 32 where the coolant is expanded, while the fourth heat exchanger 26 is idle during the cooling mode. The first heat exchanger 14, which is configured as an evaporator, receives the flow of coolant from the first expansion valve 32. The heat is transferred from the air flowing in the housing 12 to the coolant that is received by the first heat exchanger 14. The air flowing in the housing 12 is cooled and conveyed to the passenger compartment.

At the same time, the refrigerant is conveyed through the secondary flow path 30 to cool the battery 11. The direction of the flow of the refrigerant passing through the secondary flow path 30 is indicated by the arrowhead. The first valve 60 of the secondary passage 30 is closed to prevent the refrigerant from flowing through a part of the main passage 54 of the secondary passage 30. The second valve 64 of the secondary flow passage 30 is opened to allow the refrigerant to flow through the bypass passage 56 of the secondary flow passage 30.

The flow control device 58 allows the refrigerant to flow through a portion of the main path 54 of the secondary flow path 30 and through the bypass 56 and consequently flows through the second heat exchanger 16. The air cooled by the first heat exchanger (14) is carried through the second heat exchanger (16). The heat transfer from the refrigerant to the air is performed through the second heat exchanger 16 to cool the refrigerant flowing through the secondary flow path 30. The refrigerant is then transferred from the second heat exchanger 16 to the bypass path 56 of the secondary flow path 30 to cool the battery 11. [ As the refrigerant is conveyed through the bypass line 56, heat is transferred between the refrigerant flowing through the bypass line 56 of the secondary flow passage 30 and the battery 11. [ During the cooling mode, the second heat exchanger 16 conveys heat to the air from the refrigerant to at least only to substantially maintain the desired temperature of the air being carried to the passenger compartment.

3, a demister mode of the HVAC system 10 is shown. The coolant flowing through the primary flow path 20 during the demister mode is similar to the coolant flowing through the primary flow path 20 during the cooling mode shown in FIG. 2 and described above. The first direction of the flow of coolant through the primary flow path 20 is indicated by the arrowhead. The heat is transferred from the air flowing in the housing 12 to the coolant that is received by the first heat exchanger 14. The air flowing in the housing 12 is cooled and dehumidified by the first heat exchanger 14 and carried through the second heat exchanger 16.

During the demister mode, the refrigerant is transported through the secondary flow path 30 to reheat the air flowing through the housing 12. The first valve 60 of the secondary passage 30 is opened to allow the refrigerant to flow through the main passage 54 of the secondary passage 30. The second valve 64 of the secondary flow path 30 is closed to prevent the flow of the refrigerant through the first bypass path 56 of the secondary flow path 30.

The flow control device 58 allows the refrigerant to flow through the main path 54 of the secondary flow path 30. The refrigerant is conveyed through a fourth heat exchanger (26). The fourth heat exchanger 26 transfers heat from the refrigerant flowing through the primary flow path 20 to the refrigerant flowing through the secondary flow path 30 to warm the refrigerant. The warmed refrigerant is then conveyed to a second heat exchanger (46). At the same time, the second heat exchanger (16) receives the air cooled and dehumidified from the first heat exchanger (14). The second heat exchanger 16 transfers heat from the refrigerant to the air so that the air flowing through the housing 12 reheats the air before it is conveyed to the passenger compartment.

In certain embodiments, the speed of the fan 28 can be selectively adjusted to control the temperature of the air being conveyed through the second heat exchanger 16. For example, the speed of the fan 28 may be reduced so that the amount of heat transferred to the air carried through the second heat exchanger 16 is increased by the second heat exchanger 16. Conversely, the speed of the fan 28 can be raised so that the amount of heat transferred to the air carried through the second heat exchanger 16 is reduced by the second heat exchanger 16.

4, a heating mode of the HVAC system 10 is shown. In the heating mode, the coolant is conveyed through the primary flow path 20 in the second direction. The second direction of the flow of coolant through the primary flow path 20 is indicated by the arrowhead. The first valve 42 of the primary flow path 20, the second valve 44 of the primary flow path 20 and the third valve 46 of the primary flow path 20 are connected to the main Is closed to prevent the flow of coolant through the portion of path 34. The fourth valve 48 of the primary flow path 20, the fifth valve 50 of the primary flow path 20 and the sixth valve 52 of the primary flow path 20 are connected to the bypass path of the primary flow path 20, (36, 38, 40).

4, the coolant is conveyed to the first heat exchanger 14, which is compressed in the compressor 22 and then configured as a heater core. The first heat exchanger 14 transfers heat from the refrigerant to the air carried through the housing 12. This air is conveyed to the passenger compartment through the second heat exchanger 16 in an idle state. The coolant is then conveyed through a second expansion valve (33) where the coolant is expanded. The coolant is then conveyed to a third heat exchanger 24 via a fourth heat exchanger 26 in an idle state where heat is transferred from the air carried by the fan 28 to the coolant. The coolant is then delivered to the compressor 22 and compressed again by the compressor 22.

During the heating mode, the secondary flow path 30 is idle. However, in another embodiment of the invention in which the secondary flow path 30 is shown in Fig. 4 and the secondary flow path 30 includes the second bypass path 38, in order to cool the battery 11, The refrigerant can be conveyed through the second bypass passage 68 of the second bypass passage 30. The flow of refrigerant is indicated by the arrowhead.

According to this embodiment, in the heating mode, the first valve 60 of the second flow passage 30, the second valve 64 of the second flow passage 30, and the fifth valve (not shown) of the second flow passage 30 The coolant flows through the first bypass circuit 56 of the secondary flow path 30, the second bypass circuit 68 of the secondary flow path 30 and a part of the main path 54 of the secondary flow path 30 And is opened to allow flow. The third valve 70 of the secondary flow path 30 and the fourth valve 72 of the secondary flow path 30 are provided to prevent the flow of coolant through the main path 54 of the secondary flow path 30 Lt; / RTI >

The flow control device 58 allows the refrigerant to flow through the first bypass 56 of the secondary flow path 30. The refrigerant is then conveyed through a fourth heat exchanger (26). The fourth heat exchanger 26 in operation transfers heat from the refrigerant passing through the secondary flow path 30 to the refrigerant flowing through the primary flow path 20 to cool the refrigerant. The refrigerant is then conveyed back to the flow control device 58 through the second bypass 68 of the secondary flow path 30. As the refrigerant is conveyed through the first bypass 56, heat is transferred from the battery 11 to the refrigerant and the battery 11 is cooled.

Figure 5 illustrates an HVAC system 10 'in accordance with another embodiment of the present invention. The same reference numerals are used to denote substantially the same features as those described in FIGS. 1 through 4, except that the reference number is followed by a prime (') symbol. The HVAC system 10 'is similar to the HVAC system 10 except that the secondary flow path 30' is in fluid communication with the primary flow path 20 'and the secondary flow path carries the coolant through the second heat exchanger 16' And is substantially similar to the HVAC system 10 of Figs. 1 to 4 described above. The second heat exchanger 16 'is configured to transfer heat between the air flowing through the housing 12' and the coolant flowing therethrough. The secondary flow path 30'which is in fluid communication with the primary flow path 20'may be replaced by a secondary flow path 30'modified in place of the fourth heat exchanger 26 of the HVAC system 10 of Figures 1 to 4 during the demistering mode of the HVAC system 10 ' To reheat air flowing through the housing 12 '.

According to this embodiment, the primary flow path 20 'includes a seventh valve 82 disposed between the third heat exchanger 24' and the node E '. The seventh valve 82 controls the coolant flowing through a portion of the main path 34 of the primary flow path 20 '. The second circuit 30 'is connected to the seventh valve 82 and the node E from the node K of the primary flow path 20' between the third heat exchanger 24 'and the seventh valve 82, From the node K of the primary flow path 20 'extending between the third heat exchanger 24' and the seventh valve 82 to the node L of the primary flow path 20 ' 7 through the second heat exchanger 16 'to the node L of the primary flow path 20' between the valve 82 and the node E. [ The secondary flow path 30 'includes a valve 80 to control the coolant flowing therethrough. It will be appreciated that more than one valve may be employed to control the coolant flowing through the secondary flow path 30 'as needed.

FIG. 6 illustrates a cooling mode of the HVAC system 10 'according to an embodiment of the present invention. The cooling mode of the HVAC system 10 'is the same as the cooling mode of the HVAC system 10 of FIG. 2 described above except that the secondary flow path 30' and the second heat exchanger 16 ' similar. The seventh valve 82 of the primary flow path 20 'is configured to allow the coolant to flow through the portion of the main path 34' of the primary flow path 20 'between the node K and the node L . The valve 80 of the secondary flow path 30 'is closed to prevent the flow of coolant through the secondary flow path 30'.

The flow of coolant through the primary flow path 20 'is indicated by the arrow. The coolant is compressed in the compressor 22 'and then conveyed to the third heat exchanger 24'. The third heat exchanger 24 'transfers heat from the refrigerant to the air carried by the fan 28'. The heated air passing through the third heat exchanger 24 'is then carried to the atmosphere. The coolant is then conveyed to a first expansion valve 32 'where the coolant is expanded. The first heat exchanger 14 'configured as an evaporator receives the flow of coolant from the first expansion valve 32'. Heat is transferred from the air flowing in the housing 12 'to the coolant received by the first heat exchanger 14'. The air flowing in the housing 12 'is cooled and carried to the passenger compartment.

FIG. 7 illustrates a demister mode of the HVAC system 10 'according to an embodiment of the present invention. The dehumidified mode of the HVAC system 10 'is similar to that of the first embodiment except that the second heat exchanger 16' receives the flow of coolant and transfers heat from the coolant to the air flowing through the housing 12 ' 3 is similar to the demister mode of the HVAC system 10 of FIG. The seventh valve 82 of the primary flow path 20'is used to prevent the flow of coolant through the portion of the main path 34'of the primary flow path 20'between the node K and the node L Lt; / RTI > The valve 80 of the secondary flow path 30 'is opened to allow the coolant to flow through the secondary flow path 30'. The first heat exchanger 14 'cools the air flowing through the housing 12' to dehumidify the air and the second heat exchanger 16 'reheats the air before the air is conveyed to the passenger compartment.

The flow of coolant through the primary flow path 20 'and through the secondary flow path 30' is indicated by the arrow. The flow of coolant through the primary flow path 20 'is indicated by the arrow. The coolant is compressed in the compressor 22 'and then conveyed to the third heat exchanger 24'. The third heat exchanger 24 'transfers heat from the refrigerant to the air carried by the fan 28'. The heated air passing through the third heat exchanger 24 'is then carried to the atmosphere. The coolant is then delivered to the second heat exchanger 16 'in a second heat exchanger from the refrigerant flowing through the second heat exchanger 16' through the housing 12 'and thereafter the first expansion Heat is transferred to the cooled and dehumidified air flowing into the valve 32 '. The first heat exchanger 14 'configured as an evaporator receives the flow of coolant from the first expansion valve 32'. Heat is transferred from the air flowing in the housing 12 'to the coolant received by the first heat exchanger 14'. The air flowing in the housing 12 'is cooled and carried to the passenger compartment.

In certain embodiments, the speed of the fan 28 'can be selectively adjusted to control the temperature of the air carried through the second heat exchanger 16'. For example, the speed of the fan 28 'may be reduced to reduce the flow rate of air flowing through the third heat exchanger 24'. As the flow rate of the air flowing through the third heat exchanger 24 'decreases, the amount of heat transferred from the refrigerant to the air flowing through the third heat exchanger 24' is reduced. Accordingly, the amount of heat contained in the refrigerant flowing from the third heat exchanger 24 'to the second heat exchanger 16' through the second flow path 30 'in the state where the fan speed is reduced is the difference between the fan speed Is greater than the amount of heat contained in the refrigerant flowing from the third heat exchanger (24 ') to the second heat exchanger (16') through the secondary flow path (30 '). Thus, the second heat exchanger 16 'receives a refrigerant having a greater amount of heat. Accordingly, the amount of heat transferred to the air conveyed through the second heat exchanger 16 'is increased. Conversely, the speed of the fan 28 'may be raised so that the amount of heat transferred to the air carried through the second heat exchanger 16' is reduced by the second heat exchanger 16 '.

FIG. 8 illustrates a heating mode of the HVAC system 10 'according to an embodiment of the present invention. The heating mode of the HVAC system 10 'is similar to the heating mode of the HVAC system 10 of FIG. 4 described above except that the secondary flow path 30' and the second heat exchanger 16 ' similar. The seventh valve 82 of the primary flow path 20 'is configured to allow the coolant to flow through the portion of the main path 34' of the primary flow path 20 'between the node K and the node L . The valve 80 of the secondary flow path 30 'is closed to prevent the flow of coolant through the secondary flow path 30'.

The flow of coolant through the primary flow path 20 'is indicated by the arrow. The first heat exchanger 14 'heats the air flowing through the housing 12' to heat the passenger compartment. The coolant is compressed in a compressor 22 and then conveyed to a first heat exchanger 14 'configured as a heater core. The first heat exchanger 14 'transfers heat from the refrigerant to the air carried through the housing 12'. This air is conveyed to the passenger compartment through the second heat exchanger 16 'in the idle state. The coolant is then conveyed through a second expansion valve 33 ', through which the coolant is expanded. The coolant is then conveyed to the third heat exchanger 24 'where heat is transferred from the air carried by the fan 28' to the coolant. The coolant is then delivered to the compressor 22 'and compressed again by the compressor 22'. The first heat exchanger 14 'transfers heat from the refrigerant flowing therethrough to the air flowing through the housing 12' to heat the air flowing through the housing 12 'to heat the passenger compartment.

Advantageously, the HVAC system 10, 10 'efficiently utilizes the waste heat from the refrigeration system to efficiently heat, cool and dehumidify the air flowing into the passenger compartment. The primary flow paths 20 and 20 'are configured for both refrigeration facility operation and heat pump operation and incorporate secondary flow paths 30 and 30' in fluid communication with the second heat exchangers 16 and 16 ' Maintain cost, weight and package size requirements. The second heat exchanger (16, 16 ') makes the need for an HVAC system with blended doors unnecessary, which minimizes complexity, vibration, noise and occupied vehicle space. Additionally, in certain embodiments, the HVAC system 10 may cool the battery 11 of the electric vehicle to maintain the performance efficiency of the battery 11. [

From the foregoing description, one skilled in the art can readily ascertain the essential characteristics of the present invention, and various changes and modifications can be made to the present invention without departing from the spirit and scope thereof, .

10: HVAC system
11: Battery
12: hollow casing or housing
14: first heat exchanger
16: second heat exchanger
18: air inlet
20: Primary flow
22: Compressor
24: Third heat exchanger
26: fourth heat exchanger
28: Fans
30: Secondary flow
32: first expansion valve
36: first bypass
38: second bypass
40: Third bypass
42: first valve
44: second valve
46: third valve
48: fourth valve
50: fifth valve
52: Sixth valve
54: Main path
58: Flow control device

Claims (20)

As an HVAC system for an electric vehicle,
A housing (12; 12 ') having an inlet (18; 18') for receiving the flow of air and an outlet (19; 19 ') in fluid communication with the passenger compartment of the vehicle;
A first heat exchanger (14; 14 ') disposed in the housing (12; 12') and configured to receive a flow of air through the housing (12; 12 ');
Is disposed within the housing (12; 12 ') downstream from the first heat exchanger (14; 14') with respect to the direction of flow of air through the housing (12; 12 ' A second heat exchanger (16;
(22; 22 '), a third heat exchanger (24; 24') and a second heat exchanger (24; 24 ') which receive a coolant therein and are in fluid communication with the first heat exchanger , At least one expansion valve (32, 33; 32 ', 33'), and a plurality of valves (42, 44, 46, 48, 50, 52; 42 ', 44', 46 ', 48' 52 ') cooperatively cooperate with each other to define a first row of valves (42, 44, 46, 48, 50, 52; 42', 44 ', 46', 48 ' A first flow path (20; 20 ') for selectively transporting the coolant passing through the exchanger (14; 14') in the first direction and the second direction; And
Is in fluid communication with a portion of the primary flow path (20; 20 ') between the third heat exchanger (24; 24') and the at least one expansion valve (32, 33; 32 '(30; 30 ') in fluid communication with the second heat exchanger (16; 16'), the second flow path (30; 30 '
Wherein fluid communication or heat exchange communication between a part of the primary flow path (20; 20 ') and the secondary flow path (30, 30') is carried out or stopped depending on the operating mode. The method according to claim 1,
Wherein the second heat exchanger (16; 16 ') is separate from the first heat exchanger (14; 14'). The method according to claim 1,
Wherein the second heat exchanger is integrally formed with the first heat exchanger and the first heat exchanger is coupled to the first heat exchanger; Is adjacent to the heat exchanger (14; 14 '). The method according to claim 1,
Wherein the second heat exchanger (16; 16 ') has a width less than the width of the first heat exchanger (14; 14'). The method according to claim 1,
Wherein the first heat exchanger (14; 14 ') is an evaporator that receives refrigerant carried through the first heat exchanger (14; 14') in the first direction and as an evaporator Is configured as a heater core that receives the coolant carried through the heat exchanger (14; 14 '). The method according to claim 1,
The primary flow path 20 (20 ') is connected to the at least one valve 42, 44, 46, 48, 50, 52, 42', 44 ', 46', 48 ', 50', 52 '(14; 14 ') including one bypass (36, 38, 40; 36', 38 ', 40') in said second direction. The method according to claim 1,
Wherein the primary flow path (20) includes a fourth heat exchanger (26) disposed adjacent the third heat exchanger (24) and in fluid communication with the third heat exchanger (24). 8. The method of claim 7,
Wherein the secondary flow path (30) is in heat exchange communication with the primary flow path (20) and in fluid communication with the fourth heat exchanger (26). The method according to claim 1,
Wherein the secondary flow path (30; 30 ') accommodates one of a coolant and a refrigerant. 10. The method of claim 9,
The secondary flow path 30, 30 'includes at least one valve 60, 64, 70, 72, 74, 80 and a bypass line 56, 68 for selectively directing the flow direction of one of the coolant and the coolant. The HVAC system to be controlled. The method according to claim 1,
The secondary flow path (30)
Communicating with the primary flow path (20) in heat exchange,
Refrigerant; And
And a fluid control device (58) for conveying the refrigerant passing through the secondary flow path (30). The method according to claim 1,
Wherein the secondary flow path (30) is in heat exchange communication with the battery (11) of the electric vehicle. A method of operating an HVAC system of an electric vehicle,
Providing a housing (12; 12 ') having an inlet (18; 18') for receiving the flow of air and an outlet (19; 19 ') in fluid communication with the passenger compartment of the electric vehicle;
Wherein a first heat exchanger (14; 14 ') is disposed in the housing (12; 12') and a second heat exchanger is located downstream from the first heat exchanger (14; 14 ') in the direction of the flow of air in the housing Disposing a second heat exchanger (16; 16 ') in the first heat exchanger;
Providing a primary flow path (20; 20 ') configured to receive a coolant therein and to operate in at least a cooling mode, a demist mode and a heating mode, the primary flow path (20; 20' At least one expansion valve (32, 33; 32 ', 33') in fluid communication with the compressor (22; 22 '), the third heat exchanger (24; 24');
(14; 14 ') in a first direction during the cooling mode and the demister mode, and a coolant flows through the first heat exchanger (14; 14') in a second direction during the heating mode, To guide the coolant through the coolant passage; And
33 ', 32', 33 ') in fluid communication with the second heat exchanger (16; 16') and between the third heat exchanger (24; 24 ') and the at least one expansion valve (20; 20 ') in fluid communication or heat exchange communication with a portion of the primary flow path (20; 20') and in fluid communication or heat exchange communication with a portion of the primary flow path Providing a secondary flow path (30; 30 ') that is to be implemented or stopped. 14. The method of claim 13,
The secondary flow path (30; 30 ') accommodates one of a coolant and a coolant,
Wherein one of the coolant and the coolant of the secondary flow path (30; 30 ') is in fluid communication or heat exchange communication with a portion of the primary flow path (20; 20') during the demist mode and the second heat exchanger (16; 16 ') of the HVAC system. 14. The method of claim 13,
The primary flow path 20 or 20 'includes a plurality of valves 42, 44, 46, 48, 50, 52, 42', 44 ', 46', 48 ', 50', 52 ' (14, 14 ') in the first and second directions, including at least one bypass line (36, 38, 40; 36', 38 ', 40' How the HVAC system works. 14. The method of claim 13,
The secondary passage 30 communicates with the primary passage 20 in a heat exchange manner and the primary passage 20 communicates heat exchange between the primary passage 20 and the secondary passage 30 Wherein the fourth heat exchanger (26) is in fluid communication with the third heat exchanger (24) and is adjacent to the third heat exchanger (24), wherein the fourth heat exchanger Way. 14. The method of claim 13,
The secondary flow path 30 communicates with the primary flow path 20 in a heat exchange manner and receives refrigerant therein. The secondary flow path 30 includes at least one valve 60, 64, 70, 72, And at least one bypass line (56, 68) cooperating with each other to guide the refrigerant to flow through the secondary flow path (30). 18. The method of claim 17,
Disposing at least one bypass line (56, 68) in heat exchange communication with the battery (11) of the electric vehicle; And
And guiding the refrigerant to flow through the bypass passage (56, 68) of the secondary flow passage (30) to transfer heat from the battery (11) to the refrigerant during at least one of the cooling mode and the heating mode How the HVAC system works. 15. The method of claim 14,
Providing a fan (28; 28 ') adjacent to said third heat exchanger (24; 24') to carry air passing through said third heat exchanger (24; 24 '); And
Adjusting the speed of the fan (28; 28 ') to control the amount of heat transferred to the air conveyed through the housing (12; 12') by the second heat exchanger (16; 16 '≪ / RTI > A method of operating an HVAC system of an electric vehicle,
Providing a housing (12; 12 ') having an inlet (18; 18') for receiving the flow of air and an outlet (19; 19 ') in fluid communication with the passenger compartment of the electric vehicle;
Said first heat exchanger (14; 14 ') and said housing (12; 12') in said housing (12; 12 ') downstream from said first heat exchanger (14; 14' Placing a second heat exchanger (16; 16 ') within the second heat exchanger;
Providing a primary flow path (20; 20 ') configured to receive a coolant therein and to operate in at least a cooling mode, a demister mode and a heating mode, the primary flow path (20; 20' And at least one expansion valve (32, 33; 32 ', 33') in fluid communication with the first heat exchanger (22; 22 '), the third heat exchanger (24; 24';
(14; 14 ') in a first direction during the cooling mode and the demister mode, and a coolant flows through the first heat exchanger (14; 14') in a second direction during the heating mode, To guide the coolant through the coolant passage;
(24, 24 ') and at least one expansion valve (32, 33; 32') in fluid communication with said first heat exchanger 20 'during a demister mode, and the first flow path (20; 20') between the first flow path (20; 20 ') is interrupted, and fluid communication or heat exchange communication with a part of the primary flow path (20; 20') is interrupted during the cooling mode, and during the heating mode, Providing a secondary flow path (30; 30 ') in which fluid communication or heat exchange communication with a portion of the primary flow path (20; 20') is interrupted or implemented; And
And guiding one of the refrigerant and the refrigerant of the secondary flow path (30; 30 ') to flow through the second heat exchanger (16; 16') during the demister mode.

Images