Fuel cell secondary power and thermal management systems

A fuel cell secondary power and thermal management system, comprising:

• motor-generator configured to be selectively operated in a motor mode, in which it converts electrical power into rotational torque, and in a generator mode, in which it converts rotational torque into electrical power;
• a compressor coupled to the motor-generator and configured to draw in air and supply compressed air;
• a turbine coupled to the motor-generator and further coupled to receive and discharge air, the turbine configured, upon receipt of the air, to supply a drive torque to the motor-generator;
• a hydrogen gas source;
• a first heat exchanger having a first air flow circuit and a second air flow circuit and configured to transfer heat between the first and second air flow circuits, the first air flow circuit having a first air flow circuit inlet and a first air flow circuit outlet, the first air flow circuit inlet coupled to receive the compressed air from the compressor, the second air flow circuit having a second air flow circuit inlet and a second air flow circuit outlet, the second air flow circuit inlet coupled to receive the air discharged from the turbine;
• a proton exchange membrane fuel cell including a cathode air flow circuit and an anode hydrogen flow circuit, the anode hydrogen flow circuit having an anode hydrogen flow circuit inlet and an anode hydrogen flow circuit outlet, the anode hydrogen flow circuit is coupled to receive hydrogen from the hydrogen gas source via the anode hydrogen flow circuit inlet, the cathode air flow circuit having a cathode air flow circuit inlet and a cathode air flow circuit outlet, the cathode air flow circuit coupled to receive air from the first air flow circuit outlet via the cathode air flow circuit inlet, and discharge air out the cathode air flow circuit outlet;
• and
• a second heat exchanger having a third air flow circuit and a fourth air flow circuit and configured to transfer heat between the third and fourth air flow circuits, the third air flow circuit having a third air flow circuit inlet and a third air flow circuit outlet, the third air flow circuit inlet coupled to receive air from the second air flow circuit outlet, the fourth air flow circuit having a fourth air flow circuit inlet and a fourth air flow circuit outlet, the fourth air flow circuit inlet coupled to receive the air discharged from the cathode air flow circuit outlet, the fourth air flow circuit outlet coupled to supply the air to the turbine.

An aircraft, comprising:

• an aircraft fuselage;
• a fuel cell secondary power and thermal management system disposed within the fuselage, the fuel cell secondary power and thermal management system comprising:
• a compressor configured to draw in air and supply compressed air;
• a turbine coupled to receive and discharge air, the turbine configured, upon receipt of the air, to supply a drive torque;
• a first heat exchanger having a first air flow circuit and a second air flow circuit and configured to transfer heat between the first and second air flow circuits, the first air flow circuit having a first air flow circuit inlet and a first air flow circuit outlet, the first air flow circuit inlet coupled to receive the compressed air from the compressor, the second air flow circuit having a second air flow circuit inlet and a second air flow circuit outlet, the second air flow circuit inlet coupled to receive the air discharged from the turbine;
• a proton exchange membrane fuel cell including a cathode air flow circuit and an anode hydrogen flow circuit, the cathode air flow circuit having a cathode air flow circuit inlet and a cathode air flow circuit outlet, the cathode air flow circuit coupled to receive air from the first air flow circuit outlet via the cathode air flow circuit inlet, and discharge air out the cathode air flow circuit outlet;
• and
• a second heat exchanger having a third air flow circuit and a fourth air flow circuit and configured to transfer heat between the third and fourth air flow circuits, the third air flow circuit having a third air flow circuit inlet and a third air flow circuit outlet, the third air flow circuit inlet coupled to receive air from the second air flow circuit outlet, the fourth air flow circuit having a fourth air flow circuit inlet and a fourth air flow circuit outlet, the fourth air flow circuit inlet coupled to receive the air discharged from the cathode air flow circuit outlet, the fourth air flow circuit outlet coupled to supply the air to the turbine.