Mild ambient vehicular heat pump system

Abstract

A vehicular heat pump system for controlling the temperature of a passenger compartment and vehicle battery is provided. The heat pump system may include a cooling mode and a heating mode. The components of each of the respective heating and cooling circuits may include: a compressor, an AC condenser, a heat pump condenser, a cabin evaporator, a heat pump evaporator, a receiver/dryer, a plurality of expansion devices, and a plurality of flow control valves. The use of multiple evaporators and condensers eliminates the need to reverse the direction of refrigerant flow upon a change in operating mode; therefore, the position of the low-pressure side of the system remains constant in all operating modes. The low-pressure side of the system is not cooled with ambient air, minimizing the complexity of the system and eliminating the need to interrupt heating mode in order to de-ice the outside heat exchanger.

1 . A heat pump system for use in a vehicle having a battery and a passenger compartment comprising:
 a heating circuit, having a low-pressure side and a high-pressure side, the heating circuit configured to circulate refrigerant in a first operating mode, to heat the passenger compartment and cool the battery;   a cooling circuit, having a low pressure side and a high pressure side, the cooling circuit configured to circulate refrigerant in a second operating mode, to cool and dehumidify the passenger compartment and cool the battery;   wherein in the low pressure side of each of the respective heating circuit and cooling circuit remains constant during operation of the heat pump system in each of the respective first operating mode and second operating mode.   
     
     
         2 . The heat pump system of  claim 1  wherein the heating circuit further includes:
 a compressor configured to compress the refrigerant; 
 at least one low-side pressure sensor configured to monitor the pressure of the refrigerant entering the compressor; 
 at least one high-side pressure sensor configured to monitor the pressure of the refrigerant exiting the compressor; 
 a first flow control valve configured to receive refrigerant from the compressor; 
 a refrigerant-to-air heat pump condenser configured to receive refrigerant from the first flow control valve and further configured to cool and condense the refrigerant; and 
 wherein the refrigerant-to-air heat pump condenser is configured to exchange heat between the refrigerant flowing through the refrigerant-to-air heat pump condenser and air flowing across the refrigerant-to-air heat pump condenser to heat the passenger compartment. 
 
     
     
         3 . The heat pump system of  claim 2  further comprising:
 a receiver dryer configured to receive refrigerant from the refrigerant-to-air heat pump condenser and further configured to remove moisture from the refrigerant; 
 a first expansion device configured to receive refrigerant from the receiver dryer and further configured to allow the refrigerant to cool and expand; 
 a second flow control valve configured to receive refrigerant from the receiver dryer; and 
 wherein the receiver dryer is configured to expel refrigerant to one of the first expansion device and second flow control valve. 
 
     
     
         4 . The heat pump system of  claim 3  wherein the receiver dryer is configured to expel refrigerant to the first expansion device. 
     
     
         5 . The heat pump system of  claim 4  further comprising an RESS chiller configured to act as a heat pump evaporator capable of exchanging heat from air surrounding the vehicle battery to the refrigerant, the RESS chiller further configured to receive refrigerant from the first expansion device and expel refrigerant to the compressor. 
     
     
         6 . The heat pump system of  claim 3  wherein the receiver dryer is configured to expel refrigerant to the second flow control valve. 
     
     
         7 . The heat pump system of  claim 6  further comprising:
 a second expansion device configured to receive refrigerant from the second flow control valve and further configured to allow the refrigerant to cool and expand; and 
 a cabin evaporator configured to receive refrigerant from the second expansion device and expel refrigerant to the compressor, the cabin evaporator further configured to exchange heat between the refrigerant and air in the passenger compartment to cool and dehumidify the passenger compartment. 
 
     
     
         8 . The heat pump system of  claim 1  wherein the cooling circuit further comprises:
 a compressor configured to compress the refrigerant; 
 at least one low-side pressure sensor configured to monitor the pressure of the refrigerant entering the compressor; 
 at least one high-side pressure sensor configured to monitor the pressure of the refrigerant exiting the compressor; and 
 an AC condenser configured to receive refrigerant from one of the third flow control valve and the compressor, the AC condenser further configured to cool and condense the refrigerant. 
 
     
     
         9 . The heat pump system of  claim 8  wherein the AC condenser is configured to receive refrigerant from the compressor and expel refrigerant to the third flow control valve. 
     
     
         10 . The heat pump system of  claim 8  further comprising:
 a receiver dryer configured to remove moisture from the refrigerant; and 
 wherein the AC condenser is configured to receive refrigerant from the third flow control valve and expel refrigerant to the receiver dryer. 
 
     
     
         11 . The heat pump system of  claim 8  further comprising:
 a receiver dryer configured to receive refrigerant from one of the AC condenser and the third flow control valve, the receiver dryer further configured to remove moisture from the refrigerant; 
 a first thermal expansion device configured to receive refrigerant from the receiver dryer and further configured to allow the refrigerant to cool and expand; and 
 an RESS chiller configured to act as a heat pump evaporator capable of exchanging heat from air surrounding the battery to the refrigerant, the RESS chiller further configured to receive refrigerant from the first expansion device and expel refrigerant to the compressor. 
 
     
     
         12 . The heat pump system of  claim 8  further comprising:
 a receiver dryer configured to receive refrigerant from one of the AC condenser and the third flow control valve, the receiver dryer further configured to remove moisture from the refrigerant; 
 a second flow control valve configured to receive refrigerant from the receiver dryer; 
 a second expansion device configured to receive refrigerant from the second flow control valve and further configured to allow the refrigerant to cool and expand; 
 a cabin evaporator configured to receive refrigerant from the second expansion device and expel refrigerant to the compressor, the cabin evaporator further configured to exchange heat between the refrigerant and air in the passenger compartment to cool and dehumidify the passenger compartment. 
 
     
     
         13 . The heat pump system of  claim 1  wherein the heating circuit includes:
 an compressor configured to compress the refrigerant; 
 at least one low-side pressure sensor configured to monitor the pressure of the refrigerant entering the compressor; 
 at least one high-side pressure sensor configured to monitor the pressure of the refrigerant exiting the compressor; 
 a first flow control valve configured to receive refrigerant from the compressor; 
 a refrigerant-to-coolant heat pump condenser having a refrigerant cavity and a coolant cavity, the refrigerant-to-coolant heat pump condenser configured to receive refrigerant from the first flow control valve and further configured to exchange heat from refrigerant flowing through the refrigerant cavity to coolant flowing through the coolant cavity; 
 a coolant heater core configured to receive coolant from the refrigerant-to-coolant heat pump condenser and further configured to exchange heat between the coolant flowing through the coolant heater core and air flowing across the coolant heater core to the passenger compartment; 
 a receiver dryer configured to receive refrigerant from the refrigerant cavity, the receiver dryer further configured to remove moisture from the refrigerant; 
 a coolant valve configured to receive coolant from the coolant heater core; 
 a heating source configured to receive coolant from the coolant valve and further configured to warm the coolant; 
 an electric coolant pump configured to receive coolant from one of the coolant valve and heating source and further configured to expel coolant to the coolant cavity; and 
 wherein the coolant valve is configured to direct coolant to one of the heating source and the electric coolant pump. 
 
     
     
         14 . The heat pump of  claim 13  wherein the heat pump system further includes:
 a first thermal expansion device configured to receive refrigerant from the receiver dryer and further configured to allow the refrigerant to cool and expand; and 
 an RESS chiller configured to act as a heat pump evaporator capable of exchanging heat from air surrounding the vehicle battery to the refrigerant, the RESS chiller further configured to receive refrigerant from the first expansion device and expel refrigerant to the compressor. 
 
     
     
         15 . The heat pump system of  claim 13  further comprising:
 a second flow control valve configured receive refrigerant from the receiver dryer; 
 a second expansion device configured to receive refrigerant from the second flow control valve and further configured to allow the refrigerant to cool and expand; and 
 a cabin evaporator configured to receive refrigerant from the second expansion device and expel refrigerant to the compressor, the cabin evaporator further configured to exchange heat between the refrigerant and air in the passenger compartment to cool and dehumidify the passenger compartment. 
 
     
     
         16 . A vehicle comprising:
 a passenger compartment;   a vehicle battery configured to provide a power source for the vehicle;   a heat pump system including:
 a heating circuit, having a low-pressure side and a high-pressure side, the heating circuit configured to circulate refrigerant in a first operating mode, to heat the passenger compartment and cool the battery; 
 a cooling circuit, having a low-pressure side and a high-pressure side, the cooling circuit configured to circulate refrigerant in a second operating mode, to cool and dehumidify the passenger compartment and cool the battery; 
   a plurality of flow control valves, including at least a first flow control valve, a second flow control valve, and a third flow control valve, each of the respective first, second, and third flow control valves configured to receive and selectively distribute refrigerant through one of the heating circuit and cooling circuit; and   wherein the low-pressure side of each of the respective heating circuit and cooling circuit remains constant during operation of the heat pump system in each of the respective first operating mode and second operating mode.   
     
     
         17 . The vehicle of  claim 16  wherein the heating circuit includes:
 a compressor configured to compress the refrigerant; 
 at least one low-side pressure sensor configured to monitor the pressure of the refrigerant entering the compressor; 
 at least one high-side pressure sensor configured to monitor the pressure of the refrigerant exiting the compressor; 
 the first flow control valve configured to receive refrigerant from the compressor; 
 a refrigerant-to-air heat pump condenser configured to receive refrigerant from the first flow control valve and further configured to condense and cool the refrigerant, wherein the refrigerant-to-air heat pump condenser is configured to exchange heat between the refrigerant flowing through the refrigerant-to-air heat pump condenser and air flowing across the refrigerant-to-air heat pump condenser to heat the passenger compartment; 
 a receiver dryer configured to receive refrigerant from the heat pump condenser and further configured to remove moisture from the refrigerant; 
 a first expansion device configured to receive refrigerant from the receiver dryer and further configured to allow the refrigerant to cool and expand; and 
 an RESS chiller configured to act as a heat pump evaporator capable of exchanging heat from air surrounding the vehicle battery to the refrigerant, the RESS chiller further configured to receive refrigerant from the first expansion device and expel refrigerant to the compressor. 
 
     
     
         18 . The vehicle of  claim 17  wherein the heating circuit further includes:
 a compressor configured to compress the refrigerant; 
 at least one low-side pressure sensor configured to monitor the pressure of the refrigerant entering the compressor; 
 at least one high-side pressure sensor configured to monitor the pressure of the refrigerant exiting the compressor; 
 the first flow control valve configured to receive refrigerant from the compressor; 
 a refrigerant-to-air heat pump condenser configured to receive refrigerant from the first flow control valve and further configured to condense and cool the refrigerant, wherein the refrigerant-to-air heat pump condenser is configured to exchange heat between the refrigerant flowing through the refrigerant-to-air heat pump condenser and air flowing across the refrigerant-to-air heat pump condenser to heat the passenger compartment; 
 a receiver dryer configured to receive refrigerant from the heat pump condenser and further configured to remove moisture from the refrigerant; 
 the second flow control valve configured to receive refrigerant from the receiver dryer; 
 a second expansion device configured to receive refrigerant from the second flow control valve and further configured to allow the refrigerant to cool and expand; and 
 a cabin evaporator configured to receive refrigerant from the second expansion device and expel refrigerant to the compressor, the cabin evaporator further configured to exchange heat between the refrigerant and air in the passenger compartment to cool and dehumidify the passenger compartment. 
 
     
     
         19 . The vehicle of  claim 16  wherein the cooling circuit includes:
 an compressor configured to compress the refrigerant; 
 at least one low-side pressure sensor configured to monitor the pressure of the refrigerant entering the compressor; 
 at least one high-side pressure sensor configured to monitor the pressure of the refrigerant exiting the compressor; 
 an AC condenser configured to receive refrigerant from one of the second flow control valve and the compressor, the AC condenser further configured to cool and condense the refrigerant; 
 the third flow control valve configured to receive refrigerant from one of the compressor and the AC condenser; 
 a receiver dryer configured to receive refrigerant from one of the AC condenser and the third flow control valve, the receiver dryer further configured to remove moisture from the refrigerant; 
 a first expansion device configured to receive refrigerant from the receiver dryer and further configured to allow the refrigerant to cool and expand; and 
 an RESS chiller configured to act as a heat pump evaporator capable of exchanging heat from air surrounding the vehicle battery to the refrigerant, the RESS chiller further configured to receive refrigerant from the first expansion device and expel refrigerant to the compressor. 
 
     
     
         20 . The vehicle of  claim 16  wherein the cooling circuit further includes:
 a compressor configured to compress the refrigerant; 
 at least one low-side pressure sensor configured to monitor the pressure of the refrigerant entering the compressor; 
 at least one high-side pressure sensor configured to monitor the pressure of the refrigerant exiting the compressor; 
 an AC condenser configured to receive refrigerant from one of the second flow control valve and the compressor, the AC condenser further configured to cool and condense the refrigerant; 
 the third flow control valve configured to receive refrigerant from one of the compressor and the AC condenser; 
 a receiver dryer configured to receive refrigerant from one of the AC condenser and the third flow control valve, the receiver dryer further configured to remove moisture from the refrigerant; 
 the second flow control valve configured to receive refrigerant from the receiver dryer; 
 a second expansion device configured to receive refrigerant from the second flow control valve and further configured to allow the refrigerant to cool and expand; and 
 a cabin evaporator configured to receive refrigerant from the second expansion device and expel refrigerant to the compressor, the cabin evaporator further configured to exchange heat between the refrigerant and air in the passenger compartment to cool and dehumidify the passenger compartment.