Propulsion system for an aircraft

Abstract

A hybrid-electric propulsion system includes a propulsor, a turbomachine, and an electrical system having an electric machine coupled to the turbomachine. A method for operating the propulsion system includes operating, by one or more computing devices, the turbomachine to rotate the propulsor and generate thrust for the aircraft; receiving, by the one or more computing devices, data indicative of an un-commanded loss of the thrust generated from the turbomachine rotating the propulsor; and providing, by the one or more computing devices, electrical power to the electric machine to add power to the turbomachine, the propulsor, or both in response to receiving the data indicative of the un-commanded loss of thrust.

What is claimed is: 
     
         1 . A method for operating a turbomachine of a hybrid-electric propulsion system of an aircraft, the hybrid-electric propulsion system comprising a propulsor, a turbomachine, and an electrical system having an electric machine coupled to the turbomachine, the method comprising:
 operating, by one or more computing devices, the turbomachine to rotate the propulsor and generate thrust for the aircraft;   receiving, by the one or more computing devices, data indicative of an un-commanded loss of the thrust generated from the turbomachine rotating the propulsor; and   providing, by the one or more computing devices, electrical power to the electric machine to add power to the turbomachine, the propulsor, or both in response to receiving the data indicative of the un-commanded loss of thrust.   
     
     
         2 . The method of  claim 1 , wherein the electrical system further comprises an electric energy storage unit, and wherein providing, by the one or more computing devices, electrical power to the electric machine comprises providing, by the one or more computing devices, electrical power to the electric machine from the electric energy storage unit. 
     
     
         3 . The method of  claim 1 , wherein the turbomachine is a first turbomachine, wherein the electric machine is a first electric machine, wherein the hybrid electric propulsion system further comprises a second turbomachine, wherein the electrical system further comprises a second electric machine coupled to the second turbomachine, and wherein providing, by the one or more computing devices, electrical power to the electric machine comprises providing, by the one or more computing devices, electrical power to the first electric machine from the second electric machine. 
     
     
         4 . The method of  claim 1 , wherein receiving, by the one or more computing devices, data indicative of the un-commanded loss of the thrust comprises receiving, by the one or more computing devices, data indicative of a reduction in a rotational speed of the turbomachine. 
     
     
         5 . The method of  claim 1 , wherein receiving, by the one or more computing devices, data indicative of the un-commanded loss of the thrust comprises receiving, by the one or more computing devices, data indicative of an increased vibration of one or more components of the turbomachine, of the propulsor, or both. 
     
     
         6 . The method of  claim 1 , wherein receiving, by the one or more computing devices, data indicative of the un-commanded loss of the thrust comprises receiving, by one or more computing devices, data indicative of a reduced pressure within the turbomachine. 
     
     
         7 . The method of  claim 6 , wherein the data indicative of the reduced pressure within the turbomachine is indicative of a combustor blowout. 
     
     
         8 . The method of  claim 1 , further comprising:
 terminating, by the one or more computing devices, the provision of electrical power to the electric machine to add power to the turbomachine, the propulsor, or both.   
     
     
         9 . The method of  claim 8 , further comprising:
 receiving, by the one or more computing devices, data indicative of a restoration of engine operability, and wherein terminating, by the one or more computing devices, the provision of electrical power to the electric machine comprises terminating, by the one or more computing devices, the provision of electrical power to the electric machine in response to receiving, by the one or more computing devices, data indicative of the restoration of engine operability.   
     
     
         10 . The method of  claim 9 , wherein receiving, by the one or more computing devices, data indicative of the restoration of engine operability comprises receiving, by the one or more computing devices, data indicative of a restoration of the thrust generated from the turbomachine rotating the propulsor, and wherein the data indicative of the restoration of the thrust comprises data indicative of an operability parameter of the turbomachine being within a certain operability range. 
     
     
         11 . The method of  claim 9 , wherein receiving, by the one or more computing devices, data indicative of the restoration of engine operability comprises receiving, by the one or more computing devices, data indicative of a restoration of the thrust generated from the turbomachine rotating the propulsor, and wherein the data indicative of the restoration of the thrust comprises data indicative of at least one of a rotational speed of the turbomachine being above a determined threshold or a pressure within the turbomachine being above a determined threshold. 
     
     
         12 . The method of  claim 8 , further comprising:
 receiving, by the one or more computing devices, data indicative of a charge level of the electric energy storage unit, and wherein terminating, by the one or more computing devices, the provision of electrical power to the electric machine comprises terminating, by the one or more computing devices, the provision of electrical power to the electric machine in response to receiving, by the one or more computing devices, data indicative of the charge level of the electric energy storage unit.   
     
     
         13 . The method of  claim 8 , further comprising:
 receiving, by the one or more computing devices, data indicative of a health of the electric energy storage unit, and wherein terminating, by the one or more computing devices, the provision of electrical power to the electric machine comprises terminating, by the one or more computing devices, the provision of electrical power to the electric machine in response to receiving, by the one or more computing devices, data indicative of the health of the electric energy storage unit.   
     
     
         14 . The method of  claim 8 , further comprising:
 receiving, by the one or more computing devices, data indicative of a temperature of the electric machine, and wherein terminating, by the one or more computing devices, the provision of electrical power to the electric machine comprises terminating, by the one or more computing devices, the provision of electrical power to the electric machine in response to receiving, by the one or more computing devices, data indicative of the temperature of the electric machine.   
     
     
         15 . The method of  claim 1 , wherein providing, by the one or more computing devices, electrical power to the electric machine comprises transferring, by one or more computing devices, at least about ten amps of electrical power to the electric machine. 
     
     
         16 . The method of  claim 1 , wherein providing, by the one or more computing devices, electrical power to the electric machine comprises providing, by the one or more computing devices, electrical power to the electric machine such that the electric machine provides at least about fifteen horsepower of mechanical power to the turbomachine. 
     
     
         17 . The method of  claim 1 , wherein operating, by the one or more computing devices, the turbomachine to rotate the propulsor and generate thrust for the aircraft comprises extracting, by the one or more computing devices electrical power from the electric machine. 
     
     
         18 . A hybrid-electric propulsion system for an aircraft comprising:
 a propulsor;   a turbomachine coupled to the propulsor for driving the propulsor and generating thrust;   an electrical system comprising an electric machine, the electric machine coupled to the turbomachine; and   a controller configured to receive data indicative of an un-commanded loss of thrust generated from the turbomachine driving the propulsor, and further to provide electrical power to the electric machine to add power to the turbomachine, the propulsor, or both in response to receiving the data indicative of the un-commanded loss of the thrust.   
     
     
         19 . The hybrid-electric propulsion system of  claim 18 , wherein the electrical system further comprises an electric energy storage unit, and wherein in providing electrical power to the electric machine, the controller is configured to provide electrical power to the electric machine from the electric energy storage unit. 
     
     
         20 . The hybrid-electric propulsion system of  claim 18 , wherein the electric machine is configured to provide at least about sixty-five horsepower of mechanical power to the turbomachine, the propulsor, or both when electrical power is provided thereto.