Hvac-apu systems for battery electric vehicles

Abstract

A HVAC-APU system is provided for a battery electric vehicle. The system includes, but is not limited to a refrigerant fluid. A power cycle loop section, a cabin heating cycle loop section, and a cabin refrigeration cycle loop section are in selective fluid communication with each other to advance the refrigerant fluid through the system. A compressor-expander train includes, but is not limited to a reversing compressor-expander and a high-pressure pump that are operably connected by a shaft. The high-pressure pump pressurizes the refrigerant fluid to form a high-pressure refrigerant fluid. An auxiliary fuel cell and combustion unit heats a heat transfer fluid. A heat exchanger transfers heat from the heated transfer fluid to the high-pressure refrigerant fluid to form a heated high-pressure refrigerant fluid. The reversing compressor-expander expands the heated high-pressure refrigerant fluid to rotate the shaft in a first direction to drive the high-pressure pump.

1 . A HVAC-APU system for an electric vehicle, the system comprising:
 a refrigerant fluid;   a power cycle loop section configured to advance the refrigerant fluid;   a cabin heating cycle loop section in selective fluid communication with the power cycle loop section and configured to advance the refrigerant fluid;   a cabin refrigeration cycle loop section in selective fluid communication with the power cycle loop section and the cabin heating cycle loop section and configured to advance the refrigerant fluid with the power cycle loop section and the cabin heating cycle loop section;   a compressor-expander train comprising a reversing compressor-expander, a high-pressure pump and a shaft that operably couples the reversing compressor-expander with the high-pressure pump, the high-pressure pump disposed along the power cycle loop section and configured to pressurize the refrigerant fluid to form a high-pressure refrigerant fluid;   an auxiliary fuel cell and combustion unit containing a heat transfer fluid and configured to heat the heat transfer fluid to form a heated transfer fluid; and   a heat exchanger disposed along the power cycle loop section to receive the high-pressure refrigerant fluid and is in fluid communication with the auxiliary fuel cell and combustion unit to receive the heated transfer fluid, the heat exchanger configured to transfer heat from the heated transfer fluid to the high-pressure refrigerant fluid to form a heated high-pressure refrigerant fluid, wherein the reversing compressor-expander is in selective fluid communication with the heat exchanger to receive the heated high-pressure refrigerant fluid and is configured to expand the heated high-pressure refrigerant fluid to rotate the shaft in a first direction to drive the high-pressure pump.   
     
     
         2 . The system according the  claim 1 , wherein the compressor-expander train further comprises a motor generator operably coupled to the reversing compressor-expander by the shaft, and wherein the motor generator is configured to be driven by the shaft rotating in the first direction to generate electrical energy to define a power generation mode. 
     
     
         3 . The system according to  claim 2 , further comprising a battery configured to store the electrical energy generated during the power generation mode. 
     
     
         4 . The system according to  claim 2 , further comprising an electric motor configured to operably drive the electric vehicle during the power generation mode with the electrical energy. 
     
     
         5 . The system according to  claim 2 , further comprising a cabin evaporator disposed along the cabin heating cycle loop section that is in selective fluid communication with the heat exchanger and configured to receive the heated high-pressure refrigerant fluid, the cabin evaporator further configured to extract heat from the heated high-pressure refrigerant fluid for heating a passenger cabin of the electric vehicle. 
     
     
         6 . The system according to  claim 5 , wherein the system is operable in a cabin heating mode and the power generation mode when the power cycle loop section and the cabin heating cycle loop section are in fluid communication. 
     
     
         7 . The system according to  claim 5 , further comprising:
 a primary loop condenser in fluid communication with the reversing compressor-expander and configured to receive the refrigerant fluid;   an expansion valve disposed along the cabin refrigeration cycle loop section that is in selective fluid communication with the primary loop condenser to receive the refrigerant fluid;   a cabin condenser disposed along the cabin refrigeration cycle loop section that is in selective fluid communication with the primary loop condenser to receive the refrigerant fluid, the expansion valve and the cabin condenser cooperatively configured to expand and cool the refrigerant fluid for cooling the passenger cabin; and   a linear solenoid ejector AC pump in selective fluid communication with the heat exchanger and the cabin refrigeration cycle loop section and configured to receive the heated high-pressure refrigerant fluid and the refrigerant fluid, the linear solenoid ejector AC pump further configured to advance the heated high-pressure refrigerant fluid and the refrigerant fluid producing a pressure drop across the cabin refrigeration cycle loop section to advance the refrigerant fluid through the expansion valve and the cabin condenser.   
     
     
         8 . The system according to  claim 7 , wherein the system is operable in a cabin cooling mode and the power generation mode when the power cycle loop section and the cabin refrigeration cycle loop section are in fluid communication. 
     
     
         9 . The system according to  claim 7 , wherein the system is operable in a cabin demisting mode and the power generation mode when the power cycle loop section, the cabin heating cycle loop section and the cabin refrigeration cycle loop section are in fluid communication. 
     
     
         10 . The system according to  claim 7 , wherein the motor generator is configured to be driven by battery stored electrical energy to rotate the shaft in a second direction in a non-power generation mode when the reversing compressor-expander is not in fluid communication with the heat exchanger of the power cycle loop section, and wherein the reversing compressor-expander is configured to compress the refrigerant fluid when rotated by the shaft in the second direction to form a compressed refrigerant fluid. 
     
     
         11 . The system according to  claim 10 , wherein the cabin evaporator is configured to extract heat from the compressed refrigerant fluid for heating the passenger cabin when the cabin evaporator of the cabin heating cycle loop section is not in fluid communication with the heat exchanger of the power cycle loop section but is in fluid communication with the reversing compressor-expander to receive the compressed refrigerant fluid. 
     
     
         12 . The system according to  claim 10 , wherein the expansion valve and the cabin condenser are cooperatively configured to expand and cool the compressed refrigerant fluid for cooling the passenger cabin when the linear solenoid ejector AC pump is not in fluid communication with the heat exchanger of the power cycle loop section but the primary loop condenser is in fluid communication with the reversing compressor-expander to receive the compressed refrigerant fluid. 
     
     
         13 . The system according to  claim 1 , further comprising a circulation pump in fluid communication with the heat transfer fluid and operably coupled to the shaft to advance the heated transfer fluid from the auxiliary fuel cell and combustion unit to the heat exchanger in response to the shaft rotating in the first direction. 
     
     
         14 . The system according to  claim 1 , wherein the auxiliary fuel cell and combustion unit is removably connected to the system. 
     
     
         15 . A HVAC-APU system for a battery electric vehicle that has a passenger cabin, the HVAC-APU system configured to receive an auxiliary fuel cell and combustion unit that contains a heat transfer fluid and which is operable to heat the heat transfer fluid to form a heated transfer fluid, the system comprising:
 a refrigerant fluid;   a power cycle loop section, a cabin heating cycle loop section, and a cabin refrigeration cycle loop section that are in selective fluid communication with each other to advance the refrigerant fluid through the system to provide various operating modes;   a compressor-expander train comprising a reversing compressor-expander, a high-pressure pump and a shaft that operably couples the reversing compressor-expander with the high-pressure pump, the high-pressure pump disposed along the power cycle loop section and configured to pressurize the refrigerant fluid to form a high-pressure refrigerant fluid; and   a heat exchanger disposed along the power cycle loop section to receive the high-pressure refrigerant fluid, the heat exchanger configured for fluid communication with the auxiliary fuel cell and combustion unit to receive the heated transfer fluid and to transfer heat from the heated transfer fluid to the high-pressure refrigerant fluid to form a heated high-pressure refrigerant fluid, wherein the reversing compressor-expander is in selective fluid communication with the heat exchanger to receive the heated high-pressure refrigerant fluid and is configured to expand the heated high-pressure refrigerant fluid to rotate the shaft in a first direction to drive the high-pressure pump.   
     
     
         16 . The system according to  claim 15 , wherein the compressor-expander train further comprises a motor generator operably coupled to the reversing compressor-expander by the shaft, and wherein the motor generator is configured to be driven by the shaft rotating in the first direction to generate electrical energy to define a power generation mode. 
     
     
         17 . The system according to  claim 15 , further comprising a cabin evaporator disposed along the cabin heating cycle loop section that is in selective fluid communication with the heat exchanger to receive the heated high-pressure refrigerant fluid, the cabin evaporator configured to extract heat from the heated high-pressure refrigerant fluid for heating the passenger cabin. 
     
     
         18 . The system according to  claim 15 , further comprising:
 a primary loop condenser in fluid communication with the reversing compressor-expander to receive the refrigerant fluid;   an expansion valve and a cabin condenser that are disposed along the cabin refrigeration cycle loop section that is in selective fluid communication with the primary loop condenser to receive the refrigerant fluid, the expansion valve and the cabin condenser cooperatively configured to expand and cool the refrigerant fluid for cooling the passenger cabin; and   a linear solenoid ejector AC pump in selective fluid communication with the heat exchanger and the cabin refrigeration cycle loop section to receive the heated high-pressure refrigerant fluid and the refrigerant fluid, respectively, the linear solenoid ejector AC pump configured to advance the heated high-pressure refrigerant fluid and the refrigerant fluid therethrough so as to cause a pressure drop across the cabin refrigeration cycle loop section to advance the refrigerant fluid through the expansion valve and the cabin condenser.   
     
     
         19 . The system according to  claim 15 , further comprising a circulation pump operably coupled to the shaft and configured for fluid communication with the heat transfer fluid to advance the heated transfer fluid from the auxiliary fuel cell and combustion unit to the heat exchanger in response to the shaft rotating in the first direction. 
     
     
         20 . The system according to  claim 15 , further comprising a plurality of quick connects for removably connecting the auxiliary fuel cell and combustion unit to the system.