Heat pump system for a vehicle

1 . A heat pump system for a vehicle, comprising:

an air conditioner unit including a compressor, an internal condenser, a heat-exchanger, a first expansion valve, an evaporator, and an accumulator connected via a refrigerant line through which a refrigerant flows;

a chiller provided on a first connection line connected to the refrigerant line, and configured to adjust a temperature of a coolant by exchanging heat between the refrigerant supplied from the air conditioner unit via the refrigerant line and a coolant;

a second expansion valve provided on the first connection line at an upstream end of the chiller; and

a third expansion valve provided on the refrigerant line between the internal condenser and the heat-exchanger,

wherein the air conditioner unit further includes:

an internal heat-exchanger provided inside the accumulator and configured to exchange heat between the refrigerant selectively supplied from the internal condenser or the heat-exchanger and the refrigerant selectively supplied from the evaporator or the chiller, wherein the internal heat-exchanger is configured to supply a liquid refrigerant among the heat-exchanged refrigerant to the first expansion valve or the second expansion valve;

a second connection line including: a first end connected to the refrigerant line between the internal condenser and the heat-exchanger, and a second end connected to the refrigerant line between the evaporator and the accumulator; and

a third connection line including: a first end connected to the third expansion valve, and a second end connected to the refrigerant line between the heat-exchanger and the internal heat-exchanger, and

wherein a flow of the refrigerant is controlled based on at least one mode for a temperature adjustment of a vehicle interior or for a temperature adjustment of a battery module.

2 . The heat pump system of claim 1 , wherein a valve configured to selectively open or close the second connection line is provided on the second connection line.

3 . The heat pump system of claim 1 , wherein the at least one mode comprises:

a first mode for cooling the battery module while cooling the vehicle interior;

a second mode for heating the vehicle interior; and

a third mode for heating and dehumidifying the vehicle interior.

4 . The heat pump system of claim 3 , wherein, in the first mode:

the refrigerant line connecting the internal condenser and the heat-exchanger is opened by an operation of the third expansion valve;

the first connection line is opened by an operation of the second expansion valve;

the second connection line is closed; and

the third connection line is closed by the operation of the third expansion valve.

5 . The heat pump system of claim 4 , wherein:

the first expansion valve is configured to expand the refrigerant introduced via the refrigerant line such that the expanded refrigerant is supplied to the evaporator;

the second expansion valve is configured to expand the refrigerant introduced into the first connection line and flow the expanded refrigerant into the chiller to cool the battery module by using the coolant having exchanged heat with the refrigerant at the chiller; and

the third expansion valve is configured to flow the refrigerant introduced from the internal condenser into the heat-exchanger without expansion.

6 . The heat pump system of claim 4 , wherein:

the refrigerant discharged from the heat-exchanger is supplied to the internal heat-exchanger along the refrigerant line;

the refrigerant discharged from the chiller and the refrigerant discharged from the evaporator pass through the accumulator along the refrigerant line, and then are supplied to the compressor; and

the internal heat-exchanger exchanges heat between the refrigerant supplied from the heat-exchanger and the refrigerant supplied from the evaporator and the chiller.

7 . The heat pump system of claim 3 , wherein, in the second mode:

a partial refrigerant line connecting the internal condenser and a second end of the second connection line is closed by an operation of the third expansion valve;

a partial refrigerant line connecting the evaporator and a first end of the first connection line is closed by an operation of the first expansion valve;

the refrigerant line connecting from the evaporator to a second end of the first connection line is closed;

the first connection line is opened by an operation of the second expansion valve;

the second connection line is opened; and

the third connection line is opened by the operation of the third expansion valve.

8 . The heat pump system of claim 7 , wherein:

the first expansion valve stops operating;

the second expansion valve supplies the refrigerant introduced via the first connection line to the chiller without expansion; and

the third expansion valve expands the refrigerant such that the expanded refrigerant is supplied to the heat-exchanger and the chiller.

9 . The heat pump system of claim 7 , wherein:

a partial refrigerant among the refrigerant introduced from the internal condenser into the third connection line is introduced into the heat-exchanger;

a remaining refrigerant among the refrigerant introduced from the internal condenser into the third connection line is introduced into the internal heat-exchanger; and

the refrigerant flowing from the heat-exchanger via the second connection line and the refrigerant discharged from the chiller pass through the accumulator along the refrigerant line, and then are supplied to the compressor.

10 . The heat pump system of claim 3 , wherein, in the third mode:

a partial refrigerant line connecting the third expansion valve to a second end of the third connection line is closed by an operation of the third expansion valve;

the refrigerant line connecting the evaporator and the internal heat-exchanger and the refrigerant line connecting the evaporator and the accumulator are opened by an operation of the first expansion valve;

the first connection line is closed by an operation of the second expansion valve;

the second connection line is closed; and

the third connection line is opened by the operation of the third expansion valve.

11 . The heat pump system of claim 10 , wherein:

the first expansion valve expands the refrigerant introduced via the refrigerant line such that the expanded refrigerant is supplied to the evaporator;

the second expansion valve stops operating; and

the third expansion valve is configured to flow the introduced refrigerant to the third connection line without expansion.

12 . The heat pump system of claim 10 , wherein:

the refrigerant introduced into the third connection line from the internal condenser is introduced into the internal heat-exchanger along the refrigerant line; and

the internal heat-exchanger exchanges heat between the refrigerant supplied from the internal condenser and the refrigerant supplied from the evaporator.

13 . The heat pump system of claim 1 , wherein:

the second expansion valve and the third expansion valve are electronic expansion valves configured to selectively expand the refrigerant while controlling a flow of the refrigerant.

14 . The heat pump system of claim 1 , wherein the heat-exchanger is configured to condense or evaporate the refrigerant.

15 . The heat pump system of claim 1 , wherein the chiller is connected to an electrical component via a first line where the coolant circulates and connected to the battery module via a second line where the coolant circulates.

16 . The heat pump system of claim 1 , wherein:

a first end of the first connection line is connected to the refrigerant line between the internal heat-exchanger and the first expansion valve; and

a second end of the first connection line is connected to the refrigerant line between the evaporator and the accumulator.