Heat pump system for vehicle

Abstract

A heat pump system may include a cooling assembly disposed on a vehicle to circulate electric devices with coolant through a cooling line, wherein the cooling assembly includes a radiator disposed at a front side of the vehicle, uses a water pump to circulate coolant through the cooling line, and cools the supplied coolant through heat exchange with outside air, and a cooling fan that blows wind through the radiator, an air conditioning assembly connected to a refrigerant line connected to the cooling assembly to control heating and cooling, and a heat exchanger connected to the cooling line such that the coolant is circulated therein, selectively uses the waste heat generated from the electric devices according to modes to vary the temperature of the coolant, and is connected to the refrigerant line of the air conditioning assembly such that an inflow refrigerant exchanges heat with the coolant.

1 . A heat pump system, comprising:
 a cooling assembly that is disposed on a vehicle to circulate electric devices with coolant through a cooling line, wherein the cooling assembly includes a radiator that is disposed at a front side of the vehicle, uses a water pump to circulate coolant through the cooling line, and cools the supplied coolant through heat exchange with outside air, and a cooling fan that blows wind through the radiator;   an air conditioning assembly that is connected to a refrigerant line connected to the cooling assembly to control heating and cooling; and   a heat exchanger that is connected to the cooling line such that the coolant is circulated therein, selectively uses the waste heat that is generated from the electric devices according to modes to vary the temperature of the coolant, and is connected to the refrigerant line of the air conditioning assembly such that an inflow refrigerant exchanges heat with the coolant.   
     
     
         2 . The heat pump system of  claim 1 , wherein the air conditioning assembly includes:
 an HVAC (Heating, Ventilation, and Air Conditioning) module that is provided with an evaporator and an opening/closing door therein, wherein the opening/closing door is selectively closed such that outside air passing the evaporator is supplied to an inner condenser and a PTC heater according to heating, cooling, and dehumidifying modes;   a compressor that is connected to the evaporator through a refrigerant line and compresses gaseous refrigerant;   an accumulator that is disposed on the refrigerant line between the compressor and the evaporator and that supplies the compressor with gaseous refrigerant;   an outside condenser that is disposed in an engine compartment of the vehicle, is connected to the refrigerant line, and condenses refrigerant;   a first valve that selectively supplies the inner condenser or the outside condenser with the refrigerant that is exhausted from the compressor according to a mode of the vehicle;   a first expansion valve that receives the refrigerant passing the inner condenser to expands the refrigerant;   a second valve that selectively supplies the outside condenser or the heat exchanger with the expanded refrigerant received from the first expansion valve;   a third valve that selectively supplies the evaporator or the accumulator with the refrigerant passing the outside condenser or the heat exchanger; and   a second expansion valve that connects the evaporator and the third valve and expands the refrigerant that is supplied through the third valve.   
     
     
         3 . The heat pump system of  claim 2 , wherein a pressure sensor is disposed on the refrigerant line connecting the compressor with the first valve. 
     
     
         4 . The heat pump system of  claim 2 , wherein the first, second, and third valves are a type of 3-way valve. 
     
     
         5 . The heat pump system of  claim 1 , wherein the cooling assembly and the air conditioning assembly are respectively connected to a controller to be operated by a control signal of the controller. 
     
     
         6 . A heat pump system control method for a vehicle that is applied to a heat pump system that includes:
 a cooling assembly that is connected to a controller and includes a radiator, a water pump, and electric devices, each of which is connected through a cooling line;   an air conditioning assembly connected by a refrigerant line and including an HVAC (Heating, Ventilation, and Air Conditioning) module that has a plurality of valves, an expansion valve, a compressor, an accumulator, an evaporator, an outside condenser, an inner condenser, a PTC heater, and an opening/closing door; and   a heat exchanger that is connected to the cooling line and the refrigerant line, and is used to operate a heating mode, a cooling mode, and a humidifying mode according to a selection of a user,   wherein during the heating mode,   raising by the cooling assembly, the temperature of coolant that is supplied to the heat exchanger through waste heat that is generated from the electric devices and raising the temperature of refrigerant through heat exchange with the refrigerant that is supplied to the heat exchanger through the refrigerant line;   passing by the air conditioning assembly the refrigerant that is heated by the heat exchanger through the accumulator and the compressor via the refrigerant line by opening a third valve to be supplied to an inner condenser of the HAVC module by an operation of a first valve;   supplying the refrigerant passing the inner condenser to the heat exchanger by an operation of a second valve in an expanded condition through a first expansion valve; and   opening the opening/closing door such that outside air passing the evaporator of the HAVC module passes the inner condenser, and inflow outside air passes the inner condenser to heat an interior room of the vehicle in conjunction with the operation of the operation of a PTC heater.   
     
     
         7 . The heat pump system control method of  claim 6 , wherein in the cooling mode,
 operating the water pump by the cooling assembly to supply coolant to the heat exchanger and to cool the electric devices in a condition that the radiator cools inflow coolant by an operation of a cooling fan, and cools refrigerant through heat exchange with low temperature coolant according to a predetermined condition;   operating the third valve by the air conditioning assembly to supply the evaporator with expanded refrigerant such that the low temperature refrigerant that is cooled passing the outside condenser is supplied to the second expansion valve that is connected to the evaporator of the HAVC module, wherein the refrigerant that is evaporated through heat exchange with outside air in the evaporator passes the accumulator and the compressor to be compressed;   operating the first valve to open the refrigerant line that is connected to the outside condenser such that a compressed refrigerant is supplied to the outside condenser; and   closing the opening/closing door such that the outside air passes the evaporator to be cooled by the refrigerant supplied to the evaporator and is directly supplied to an interior room of a vehicle and that the cooled outside air is not supplied to the inner condenser.   
     
     
         8 . The heat pump system control method of  claim 6 , wherein in the dehumidification mode,
 cooling the coolant that is supplied to the radiator by the operation of the cooling fan of the cooling assembly, cooling the electric devices through the operation of the water pump, supplying the coolant to the heat exchanger, and cooling the refrigerant by exchanging heat with the coolant supplied to the heat exchanger;   opening the third valve by the air conditioning assembly such that the coolant that is cooled while passing the heat exchanger is supplied to the second expansion valve that is connected to the evaporator of the HAVC, so as to supply the expanded refrigerant to the evaporator, wherein the refrigerant that is evaporated through heat exchange with outside air in the evaporator passes the accumulator and the compressor to be compressed;   operating the first valve to open the refrigerant line that is connected to the inside condenser such that the compressed refrigerant is supplied to the inside condenser;   operating the second valve to supply the refrigerant passing the inner condenser to the heat exchanger in an expanded condition through the first expansion valve,   opening the opening/closing door such that outside air passing the evaporator of the HAVC module passes the inner condenser, and inflow outside air passes the inner condenser and the PTC heater to dehumidify an interior room of the vehicle.   
     
     
         9 . The heat pump system control method of  claim 8 , wherein in the dehumidification mode, the controller controls an opening rate of the first and second expansion valves to control an expansion rate of the refrigerant. 
     
     
         10 . The heat pump system control method of  claim 6 , wherein in the heating mode, cooling mode, and dehumidification mode, the controller controls operating power of the cooling fan and flowing rate of the water pump according to the temperature of the waste heat that is generated from the electric devices and the temperature of the coolant and the refrigerant. 
     
     
         11 . The heat pump system of  claim 1 , further comprising a four valve that is configured to make coolant to bypass the radiator according to a heating mode and a dehumification mode.