Uncontrollable high thrust (UHT) protection for hybrid-electric aircraft propulsion systems

1 . A propulsion system for an aircraft, the propulsion system comprising:

a propulsor;

an engine including an engine output shaft, a combustor, and a fuel system, the engine output shaft coupled with the propulsor, the fuel system connected in fluid communication with the combustor, the fuel system including a fuel control unit operable to control fuel flow from the fuel system to the combustor;

an electrical assembly including an electric motor and a motor control unit, the electric motor coupled with the propulsor, the motor control unit electrically connected with the electric motor;

an engine controller including a first controller channel, the first controller channel includes a first processing system, the first processing system operable to control the fuel control unit to direct fuel to the combustor and to control the motor control unit to direct electrical power to the electric motor;

a sensor assembly including at least one propulsor sensor; and

an uncontrollable high thrust (UHT) protection assembly including a first protection circuit of the first controller channel, the first protection circuit connected in signal communication with the at least one propulsor sensor, the first protection circuit operable to identify a presence or an absence of a UHT condition of the propulsor in response to one or both of a propulsor rotation speed or a propulsor torque from the at least one propulsor sensor and, in response to identifying the presence of the UHT condition, generate a shutdown signal for the fuel control unit and the motor control unit, the presence of the UHT condition identified by the first protection circuit where the one or both of the propulsor rotation speed or the propulsor torque is greater than a respective UHT threshold value.

2 . The propulsion system of claim 1 , wherein the respective UHT threshold value is between 110 percent and 150 percent of the one or both of the propulsor rotation speed or the propulsor torque.

3 . The propulsion system of claim 2 , wherein the respective UHT threshold value is between 120 percent and 130 percent of the one or both of the propulsor rotation speed or the propulsor torque.

4 . The propulsion system of claim 1 , wherein the engine controller further includes a first output circuit connected in signal communication with and between the first processing system, the first watchdog circuit, and the fuel control unit, the first output circuit operable to receive the shutdown signal from the first protection circuit and, in response to receiving the shutdown signal, control the fuel control unit to stop fuel flow to the combustor.

5 . The propulsion system of claim 1 , wherein the motor control unit includes a motor control unit channel, the motor control unit channel is connected in signal communication with the first processing system, the motor control unit channel is operable to receive a control signal output from the first processing system and, in response to the received control signal output, control the motor control unit to supply electrical power to the electric motor.

6 . The propulsion system of claim 5 , wherein the uncontrollable high thrust (UHT) protection assembly includes a deenergization circuit at the motor control unit, the deenergization circuit is connected in signal communication with the first protection circuit, the deenergization circuit is operable to receive the shutdown signal from the first protection circuit and, in response to receiving the shutdown signal, control the motor control unit to deenergize the electric motor.

7 . The propulsion system of claim 1 , wherein the engine controller further includes a second controller channel including a second processing system, the second processing system operable to control, in combination with the first processing system, the fuel control unit to direct fuel to the combustor.

8 . The propulsion system of claim 1 , wherein the first protection circuit is operable to generate and transmit a reset signal to the first processing system in response to identifying the presence of the UHT condition.

9 . The propulsion system of claim 1 , wherein the at least one propulsor sensor is disposed mechanically downstream of a coupling interface between the engine output shaft and the electric motor.

10 . The propulsion system of claim 1 , wherein the propulsion system further includes a gear box coupling the engine output shaft and the electric motor with the propulsor.

11 . A propulsion system for an aircraft, the propulsion system comprising:

a propulsor;

an engine including an engine output shaft, a combustor, and a fuel system, the engine output shaft coupled with the propulsor, the fuel system connected in fluid communication with the combustor, the fuel system including a fuel control unit operable to control fuel flow from the fuel system to the combustor;

an electrical assembly including an electric motor and a motor control unit, the electric motor coupled with the propulsor, the motor control unit electrically connected with the electric motor;

an engine controller including a first controller channel, the first controller channel including a first processing system, the first processing system including a processor connected in signal communication with a non-transitory memory storing instructions which, when executed by the processor, cause the processor to:

generate a first control signal output for the fuel control unit to direct fuel to the combustor, and

generate a second control signal output for the motor control unit to direct electrical power to the electric motor;

a sensor assembly including at least one propulsor sensor; and

an uncontrollable high thrust (UHT) protection assembly including a first protection circuit of the first controller channel, the first protection circuit connected in signal communication with the at least one propulsor sensor, the first protection circuit operable to identify a presence or an absence of a UHT condition of the propulsor in response to one or both of a propulsor rotation speed or a propulsor torque from the at least one propulsor sensor and, in response to identifying the presence of the UHT condition, generate a shutdown signal for the fuel control unit and the motor control unit overriding the first control signal output and the second control signal output, the presence of the UHT condition identified by the first protection circuit where the one or both of the propulsor rotation speed or the propulsor torque is greater than a respective UHT threshold value.

12 . The propulsion system of claim 11 , wherein the engine controller further includes a first output circuit connected in signal communication with and between the first processing system, the first watchdog circuit, and the fuel control unit, the first output circuit operable to receive the shutdown signal from the first protection circuit and, in response to receiving the shutdown signal, control the fuel control unit to stop fuel flow to the combustor.

13 . The propulsion system of claim 11 , wherein the motor control unit includes a motor control unit channel, the motor control unit channel is connected in signal communication with the first processing system, the motor control unit channel is operable to receive a control signal output from the first processing system and, in response to the received control signal output, control the motor control unit to supply electrical power to the electric motor.

14 . The propulsion system of claim 13 , wherein the UHT protection assembly includes a deenergization circuit at the motor control unit, the deenergization circuit is connected in signal communication with the first protection circuit, the deenergization circuit is operable to receive the shutdown signal from the first protection circuit and, in response to receiving the shutdown signal, control the motor control unit to deenergize the electric motor.

15 . The propulsion system of claim 11 , wherein the first protection circuit is operable to generate and transmit a reset signal to the first processing system in response to identifying the presence of the UHT condition.

16 . A propulsion system for an aircraft, the propulsion system comprising:

a propulsor;

a gear box coupled with the propulsor;

an engine including an engine output shaft, a combustor, and a fuel system, the engine output shaft coupled with the propulsor by the gear box, the fuel system connected in fluid communication with the combustor, the fuel system including a fuel control unit operable to control fuel flow from the fuel system to the combustor;

an electrical assembly including an electric motor and a motor control unit, the electric motor coupled with the propulsor by the gear box, the motor control unit electrically connected with the electric motor;

an engine controller including a first controller channel, the first controller channel includes a first processing system, the first processing system operable to control the fuel control unit to direct fuel to the combustor and to control the motor control unit to direct electrical power to the electric motor;

a sensor assembly including at least one propulsor sensor disposed at the propulsor; and

an uncontrollable high thrust (UHT) protection assembly including a first protection circuit of the first controller channel, the first protection circuit connected in signal communication with the at least one propulsor sensor, the first protection circuit operable to identify a presence or an absence of a UHT condition of the propulsor in response to one or both of a propulsor rotation speed or a propulsor torque from the at least one propulsor sensor and, in response to identifying the presence of the UHT condition, generate a shutdown signal for the fuel control unit and the motor control unit.

17 . The propulsion system of claim 16 , wherein the motor control unit includes a motor control unit channel, the motor control unit channel is connected in signal communication with the first processing system, the motor control unit channel is operable to receive a control signal output from the first processing system and, in response to the received control signal output, control the motor control unit to supply electrical power to the electric motor.

18 . The propulsion system of claim 17 , wherein the UHT protection assembly includes a deenergization circuit at the motor control unit, the deenergization circuit is connected in signal communication with the first protection circuit, the deenergization circuit is operable to receive the shutdown signal from the first protection circuit and, in response to receiving the shutdown signal, control the motor control unit to deenergize the electric motor.

19 . The propulsion system of claim 16 , wherein the engine controller further includes a second controller channel including a second processing system, the second processing system operable to control, in combination with the first processing system, the fuel control unit to direct fuel to the combustor.

20 . The propulsion system of claim 16 , wherein the first protection circuit is operable to generate and transmit a reset signal to the first processing system in response to identifying the presence of the UHT condition.