Bleedless environmental control system

Abstract

An environmental control system of a vehicle includes an air conditioning system having a first inlet for a first medium, a second inlet for a second medium, and a first thermodynamic device including a first compressor, a first electric motor and a first turbine operably coupled by a first shaft. An air supply system includes a second thermodynamic device fluidly coupled to the air conditioning system. The second thermodynamic device includes a second compressor operably coupled to a second electric motor by a second shaft. The second thermodynamic device is fluidly coupled to and is arranged upstream from the first inlet relative to a flow of the first medium and is fluidly coupled to and is arranged downstream from the second inlet relative to a flow of the second medium. The second electric motor is fluidly coupled to and is cooled by the second medium provided at the second inlet.

What is claimed is: 
     
         1 . An environmental control system of a vehicle, the environmental control system comprising:
 an air conditioning system having:
 a first inlet configured to receive a first medium and a second inlet configured to receive a second medium; 
 a first thermodynamic device including a first shaft, a first compressor, a first electric motor and a first turbine, the first compressor, first electric motor and first turbine being operably coupled by the first shaft; 
 an air supply system including a second thermodynamic device fluidly coupled to the air conditioning system, the second thermodynamic device including a second shaft, a second compressor, and a second electric motor, the second compressor being operably coupled to the second electric motor by the second shaft; 
 wherein the second thermodynamic device is fluidly coupled to and is arranged upstream from the first inlet relative to a flow of the first medium; 
 wherein the second thermodynamic device is fluidly coupled to and is arranged downstream from the second inlet relative to a flow of the second medium; and 
 wherein the second electric motor is fluidly coupled to and is cooled by the second medium provided at the second inlet. 
   
     
     
         2 . The environmental control system of  claim 1 , wherein the flow of the second medium is configured to make a plurality of passes over the second electric motor. 
     
     
         3 . The environmental control system of  claim 1 , wherein the second thermodynamic device further comprises a second turbine operably coupled to the second compressor and the second electric motor by the second shaft. 
     
     
         4 . The environmental control system of  claim 3 , wherein the second turbine is arranged directly downstream from the second electric motor relative to the flow of the second medium. 
     
     
         5 . The environmental control system of  claim 3 , wherein the air conditioning system includes a ram air circuit having at least one ram heat exchanger and an outlet of the second turbine is fluidly connected to the ram air circuit at a location downstream from the at least one ram heat exchanger. 
     
     
         6 . The environmental control system of  claim 5 , wherein the second compressor has a second compressor outlet, the second compressor outlet being fluidly connected to and arranged in series with the at least one ram heat exchanger. 
     
     
         7 . The environmental control system of  claim 5 , further comprising a high-pressure water separator positioned directly downstream from the at least one ram heat exchanger. 
     
     
         8 . The environmental control system of  claim 3 , wherein in a first mode, the second compressor is driven solely by the second electric motor. 
     
     
         9 . The environmental control system of  claim 8 , wherein in a second mode, the second compressor is driven by the second electric motor and by energy extracted from the second medium at the second turbine. 
     
     
         10 . The environmental control system of  claim 1 , wherein the first electric motor is fluidly connected to the second inlet such that at least a portion of the second medium is provided to the first electric motor to cool the first electric motor. 
     
     
         11 . The environmental control system of  claim 1 , wherein the first electric motor is fluidly connected to the second electric motor in series relative to the flow of the second medium. 
     
     
         12 . The environmental control system of  claim 1 , wherein the environmental control system is part of an aircraft and the first medium is fresh air. 
     
     
         13 . The environmental control system of  claim 1 , wherein the second medium is cabin air. 
     
     
         14 . A method of operating an environmental control system of a vehicle, the method comprising:
 compressing a first medium at an air supply system to form a compressed first medium, the air supply system including a thermodynamic device fluidly coupled to an air conditioning system, the thermodynamic device including a shaft, a compressor, and an electric motor, the compressor being operably coupled to the electric motor by the shaft;   cooling the electric motor via a flow of second medium provided from the air conditioning system; and   delivering both the compressed first medium and the flow of second medium to a ram air circuit of the air conditioning system from the air supply system, wherein the ram air circuit includes at least one ram heat exchanger and the flow of second medium is delivered to the ram air circuit downstream from the at least one ram heat exchanger.   
     
     
         15 . The method of  claim 14 , wherein the at least one ram heat exchanger includes a plurality of ram heat exchangers, and the flow of second medium is delivered to the ram air circuit downstream from each of the plurality of ram heat exchangers. 
     
     
         16 . The method of  claim 14 , further comprising cooling the compressed first medium within the at least one ram heat exchanger. 
     
     
         17 . The method of  claim 16 , wherein cooling the compressed first medium within the at least one ram heat exchanger includes drawing a flow of ram air through the ram air circuit via a fan. 
     
     
         18 . The method of  claim 14 , further comprising extracting energy from the flow of second medium at the thermodynamic device to form an expanded second medium, wherein the extracting energy occurs directly downstream from cooling the electric motor. 
     
     
         19 . The method of  claim 14 , wherein the air conditioning system includes another thermodynamic device including another compressor, another electric motor, and a turbine operably coupled by another shaft, the method further comprising cooling the another electric motor via the flow of second medium. 
     
     
         20 . The method of  claim 19 , wherein cooling the another electric motor via the flow of second medium occurs after cooling the electric motor with the flow of second medium.