CN-122008805-A - Vehicle heating ventilation air conditioning system

Abstract

A vehicle heating, ventilation and air conditioning system includes a compressor, an internal condenser disposed at a downstream side of the compressor, a heat exchanger disposed at a downstream side of the internal condenser, wherein the heat exchanger is configured to perform heat transfer between a refrigerant and a coolant circulating in a coolant system, an evaporator disposed at a downstream side of the heat exchanger and disposed at an upstream side of the compressor, a first bypass line connecting a downstream point of the heat exchanger and an upstream point of the compressor, and a second bypass line connecting the downstream point of the internal condenser and the upstream point of the evaporator.

Inventors

• Wen Shengxuan
• Jin Taihan
• Song Zaixian
• YUAN ZHONGWEN
• HONG HUANYI
• Li Mingui
• JIN ZHEMIN

Assignees

• 现代自动车株式会社
• 起亚株式会社
• 株式会社斗源空调

Dates

Publication Date

20260512

Application Date

20250516

Priority Date

20241112

Claims (20)

1. 1. A vehicle hvac system comprising: A compressor; an internal condenser disposed on a downstream side of the compressor; A heat exchanger disposed on a downstream side of the internal condenser, wherein the heat exchanger is configured to perform heat transfer between a refrigerant and a coolant circulating in a coolant system; An evaporator provided on a downstream side of the heat exchanger and on an upstream side of the compressor; a first bypass line connecting a downstream point of the heat exchanger and an upstream point of the compressor, and A second bypass line connecting a point downstream of the internal condenser and a point upstream of the evaporator.
2. 2. The vehicle hvac system of claim 1, further comprising an external heat exchanger disposed between the heat exchanger and the evaporator, wherein the external heat exchanger is configured to transfer heat between refrigerant and ambient air, wherein the first bypass line is configured to enable at least a portion of refrigerant discharged from the heat exchanger to be directed from an upstream point of the external heat exchanger to an upstream point of the compressor.
3. 3. The vehicle hvac system of claim 2, further comprising: A cooling-side expansion valve provided between the external heat exchanger and the evaporator, and A heating side expansion valve disposed between the heat exchanger and the internal condenser, wherein the second bypass line is configured to enable at least a portion of refrigerant discharged from the internal condenser to be directed from an upstream point of the heating side expansion valve to an upstream point of the evaporator.
4. 4. The vehicle hvac system of claim 2, further comprising a control valve configured to control a flow of refrigerant in a manner that enables refrigerant discharged from the heat exchanger to be directed to at least one of the external heat exchanger and the compressor.
5. 5. The vehicle hvac system of claim 4, wherein the control valve comprises: An inlet in communication with the heat exchanger; A first outlet in communication with the external heat exchanger, and A second outlet in communication with the first bypass line.
6. 6. The vehicle hvac system of claim 5, wherein the control valve is configured to be switched such that the inlet is fluidly connectable to at least one of the first outlet and the second outlet.
7. 7. The vehicle hvac system of claim 5, wherein the control valve is configured to be switched to enable the inlet to be fluidly connected to the second outlet based on the vehicle hvac system operating in a heating mode.
8. 8. The vehicle heating, ventilation and air conditioning system according to claim 1, further comprising an auxiliary expansion valve provided on the second bypass line, wherein the auxiliary expansion valve is provided on an upstream side of the evaporator on the second bypass line.
9. 9. The vehicle hvac system of claim 8, wherein the auxiliary expansion valve is configured to fully open based on the vehicle hvac system operating in a heating mode.
10. 10. The vehicle hvac system of claim 1, further comprising a regulator valve disposed between the evaporator and the compressor, wherein the regulator valve is configured to regulate an opening thereof to regulate a flow rate of refrigerant discharged from the evaporator.
11. 11. The vehicle hvac system of claim 1, wherein the coolant system is a power electronics coolant system, and wherein the heat exchanger comprises: a first passage through which the refrigerant passes, and A second passage through which coolant passes, wherein the second passage of the heat exchanger is fluidly connected to the power electronics coolant system.
12. 12. A vehicle hvac system comprising: a power electronics cooling system; A compressor; an internal condenser downstream of the compressor; An evaporator; A power electronics heat exchanger thermally connected to the power electronics cooling system, wherein the power electronics heat exchanger is located downstream of the internal condenser; An external heat exchanger, wherein the external heat exchanger is located downstream of the power electronics heat exchanger, and wherein the external heat exchanger is located upstream of the evaporator; a cooling-side expansion valve provided between the exterior heat exchanger and the evaporator; A refrigerant circulation line configured to flow a refrigerant through the vehicle hvac system, wherein the refrigerant circulation line includes: A first refrigerant line extending from an outlet of the compressor to the internal condenser, A second refrigerant line extending from the internal condenser to the power electronics heat exchanger, A third refrigerant line extending from the power electronics heat exchanger to the external heat exchanger, A fourth refrigerant line extending from the exterior heat exchanger to the cooling side expansion valve, A fifth refrigerant line extending from the cooling side expansion valve to the evaporator, A sixth refrigerant line extending from the evaporator to an inlet of the compressor, A seventh refrigerant line extending through the power electronics heat exchanger, an A first bypass refrigerant line having a first end connected to a first connection point on the sixth refrigerant line; A control valve located between the power electronic heat exchanger, the external heat exchanger, and the first bypass refrigerant line, wherein the control valve is connected to a second end of the first bypass refrigerant line, wherein the third refrigerant line extends from the control valve to the external heat exchanger, and wherein the control valve is configured to control a flow of refrigerant discharged from the seventh refrigerant line of the power electronic heat exchanger to achieve at least one of routing to the external heat exchanger via the third refrigerant line and routing to the compressor via the sixth refrigerant line.
13. 13. The vehicle hvac system of claim 12, wherein the refrigerant cycle line further comprises a second bypass refrigerant line having a first end connected to a second connection point on the second refrigerant line between the interior condenser and the power electronics heat exchanger, and wherein a second end of the second bypass refrigerant line is connected to a third connection point on the fifth refrigerant line between the cooling side expansion valve and the evaporator.
14. 14. The vehicle hvac system of claim 13, further comprising an auxiliary expansion valve located on the second bypass refrigerant line, wherein the auxiliary expansion valve is configured to regulate flow of refrigerant into the evaporator via the third connection point on the fifth refrigerant line and from the interior condenser via the second connection point on the second refrigerant line.
15. 15. The vehicle hvac system of claim 12, further comprising a heating side expansion valve located on the second refrigerant line between the internal condenser and the power electronics heat exchanger.
16. 16. The vehicle hvac system of claim 12, further comprising an hvac housing, wherein the internal condenser is at least partially located in the hvac housing, and wherein the evaporator is at least partially located in the hvac housing.
17. 17. The vehicle hvac system of claim 12, further comprising a battery cooler, wherein the refrigerant circulation line further comprises a distribution refrigerant line connected to the fourth refrigerant line between the exterior heat exchanger and the cooling side expansion valve, connected to the sixth refrigerant line, and extending through the battery cooler.
18. 18. A vehicle hvac system comprising: a power electronics cooling system; A compressor; an internal condenser downstream of the compressor; An evaporator; A power electronics heat exchanger thermally connected to the power electronics cooling system, wherein the power electronics heat exchanger is located downstream of the internal condenser; An external heat exchanger, wherein the external heat exchanger is located downstream of the power electronics heat exchanger, and wherein the external heat exchanger is located upstream of the evaporator; a cooling-side expansion valve provided between the exterior heat exchanger and the evaporator; A refrigerant circulation line configured to flow a refrigerant through the vehicle hvac system, wherein the refrigerant circulation line includes: A first refrigerant line extending from an outlet of the compressor to the internal condenser, A second refrigerant line extending from the internal condenser to the power electronics heat exchanger, A third refrigerant line extending from the power electronics heat exchanger to the external heat exchanger, A fourth refrigerant line extending from the exterior heat exchanger to the cooling side expansion valve, A fifth refrigerant line extending from the cooling side expansion valve to the evaporator, A sixth refrigerant line extending from the evaporator to an inlet of the compressor, A seventh refrigerant line extending through the power electronics heat exchanger, A first bypass refrigerant line having a first end connected to a first connection point on the sixth refrigerant line, and A second bypass refrigerant line having a first end connected to a second connection point on the second refrigerant line between the internal condenser and the power electronics heat exchanger and a second end connected to a third connection point on the fifth refrigerant line between the cooling side expansion valve and the evaporator, and A control valve located between the power electronic heat exchanger, the external heat exchanger, and the first bypass refrigerant line, wherein the control valve is connected to a second end of the first bypass refrigerant line, wherein the third refrigerant line extends from the control valve to the external heat exchanger, and wherein the control valve is configured to control a flow of refrigerant discharged from the seventh refrigerant line of the power electronic heat exchanger to achieve at least one of routing to the external heat exchanger via the third refrigerant line and routing to the compressor via the sixth refrigerant line.
19. 19. The vehicle hvac system of claim 18, further comprising an auxiliary expansion valve located on the second bypass refrigerant line, wherein the auxiliary expansion valve is configured to regulate flow of refrigerant into the evaporator via the third connection point on the fifth refrigerant line and from the interior condenser via the second connection point on the second refrigerant line.
20. 20. The vehicle hvac system of claim 19, further comprising a heating side expansion valve located on the second refrigerant line between the second connection point on the second refrigerant line and the power electronics heat exchanger.

Description

Vehicle heating ventilation air conditioning system Cross Reference to Related Applications The present application is based on and claims the benefit of priority of korean patent application No. 10-2024-0160361 filed to korean intellectual property office on 11/12 of 2024, the disclosure of which is incorporated herein by reference in its entirety. Technical Field The present invention relates to a vehicle heating, ventilation and air conditioning (HVAC) system. Background In recent years, with increasing attention to energy efficiency and environmental problems, development of an environmentally friendly vehicle capable of replacing an internal combustion engine vehicle has been demanded. Such environmentally friendly vehicles are classified into electric vehicles driven using a fuel cell or electric power as a power source and hybrid vehicles driven using an engine and a battery. An electric or hybrid vehicle may include a heating, ventilation, and air conditioning (HVAC) system for air conditioning of a cabin (or passenger compartment). The HVAC system may be configured to heat and cool air in the cabin for passenger comfort. To ensure travel safety, an electric or hybrid vehicle may include a Power Electronics (PE) cooling system that maintains PE components of the PE system at an appropriate temperature, and a battery cooling system that maintains the battery at an appropriate temperature. The PE cooling system may cool PE components, such as a motor, an inverter, an on-board charger (OBC), and a low-voltage direct-current converter (LDC), thereby maintaining the PE components at respective appropriate temperatures. The battery cooling system may cool the battery to maintain the battery at its proper temperature. The refrigerant circulating in the HVAC system of the electric vehicle may be configured to absorb heat from the PE coolant circulating in the PE cooling system through the water-cooled heat exchanger and be evaporated. However, at relatively low ambient temperatures (e.g., -20 ℃ to-5 ℃) the temperature of the PE coolant may be relatively reduced, and thus the refrigerant may not sufficiently absorb heat from the PE coolant. Therefore, evaporation of the refrigerant is reduced, and the suction pressure of the compressor may be reduced below the threshold pressure. When the suction pressure of the compressor is lower than a threshold pressure (e.g., 0.2kgf/cm 2), the efficiency of the compressor is lowered, and thus the RPM of the compressor may be lowered below the threshold RPM, or the compressor may be stopped due to a low-pressure protection function. Accordingly, the flow rate of the refrigerant may be relatively reduced, and the temperature of the refrigerant discharged from the compressor may be relatively reduced, so that a coefficient of performance (COP) of the HVAC system may be deteriorated. Since the heating of the cabin using the refrigerant is not smoothly performed, but the cabin is heated by the electric heater, the electric efficiency of the electric vehicle may be lowered. In the HVAC system according to the related art, since the amount of heat absorption of the refrigerant is reduced in the case where the ambient temperature is relatively low, the suction pressure of the compressor may be relatively reduced. Therefore, since the RPM of the compressor is reduced or stopped, the heating of the cabin using the refrigerant may not be smoothly performed, and the cabin may need an electric heater to heat, so that the electric efficiency of the electric vehicle is reduced. The above information described in this background section is provided to assist in understanding the background of the invention and may include technical concepts that are not believed to be prior art that have been disclosed as being known, available or in use. Disclosure of Invention The present invention relates to a vehicle heating, ventilation and air conditioning (HVAC) system, and more particularly to a vehicle HVAC system designed to use a refrigerant to improve heating performance, thereby improving electrical efficiency of an electric vehicle. The embodiments of the present invention can solve the above-mentioned problems occurring in the prior art while keeping the advantages achieved by the prior art intact. Embodiments of the present invention may provide a vehicle heating, ventilation and air conditioning (HVAC) system designed to improve heating performance using a refrigerant, thereby improving electrical efficiency of an electric vehicle. According to an embodiment of the present invention, a vehicle HVAC system may include a compressor, an internal condenser disposed at a downstream side of the compressor, a heat exchanger disposed at a downstream side of the internal condenser and configured to transfer heat between a refrigerant and a coolant circulating in the coolant system, an evaporator disposed at a downstream side of the heat exchanger and disposed at an upstream side of the compress