Granted Patent B2

US 12,460,587 · App. 18/718,701 · Granted Nov 4, 2025

Inventors: David Bernard Martin Lemay (Moissy-Cramayel, FR); Jean-Philippe Jacques Marin (Moissy-Cramayel, FR); Jean-Luc Charles Gilbert Frealle (Moissy-Cramayel, FR)

Assignee: SAFRAN HELICOPTER ENGINES

F02C9/46B64D27/33B64D31/14B64D31/18B64D31/06

Abstract

Claims (48)

1 . A method for controlling the rotational speed (N p ) of a propulsion device of a hybrid propulsion unit for an aircraft, in the event of failure of the main regulation system of the heat engine of the hybrid propulsion unit, the hybrid propulsion unit comprising:

the propulsion device and a main gearbox, capable of driving the propulsion device;

the heat engine and at least one electric motor, mounted in parallel on the main gearbox, the heat engine being provided with a fuel circuit capable of supplying fuel into a combustion chamber of the heat engine;

a main regulation system of the heat engine, capable of regulating the rotational speed of the heat engine;

a backup regulation system of the heat engine, capable of regulating the rotational speed of the heat engine when the main regulation system fails;

a regulation system of the electric motor, capable of regulating the rotational speed of the electric motor;

a control system of the aircraft, capable of sending a speed or power setpoint to each of the regulation systems of the heat engine and of the electric motor;

the method comprising, when the main regulation system of the heat engine fails and said system is locked to a fuel flow command QCarbP*, the control system is performing the steps of:

sending a speed setpoint N M2ref to the regulation system of the electric motor, so that the regulation system of the electric motor sends a power command P M2* to the electric motor, whereby an instantaneous power P M2m of the electric motor is obtained;

simultaneously, sending a rotational speed or power setpoint to the backup regulation system of the heat engine, so that the backup regulation system sends a fuel flow command QCarbAux* to the fuel circuit of the heat engine, the command QCarbAux* is selected so as to vary the fuel flow QCarb injected into the combustion chamber of the heat engine depending on whether it is desired to vary the power P M1 Of the heat engine; and

controlling the rotational speed (N p ) of a propulsion device by controlling an auxiliary fuel flow QCarbAux* and the fuel flow QCarb injected into a combustion chamber of the heat engine.

2 . The method according to claim 1 , wherein, a reference power setpoint of the electric motor P M2ref* being sent to the backup regulation system of the heat engine, the fuel flow command QCarbAux* is selected by comparing the instantaneous power P M2m of the electric motor with the reference power P M2ref , and

if P M2m <P M2ref , an auxiliary fuel flow QCarbAux* is controlled such that it reduces the fuel flow QCarb injected into the combustion chamber of the heat engine, thereby reducing the power P M1 of the heat engine;

if P M2m >P M2ref , an auxiliary fuel flow QCarbAux* such that it increases the fuel flow QCarb injected into the combustion chamber of the heat engine, thereby increasing the power P M1 of the heat engine;

if P M2m =P M2ref , the flow command QCarbAux* is kept constant.

3 . The method according to claim 1 , wherein a rotational speed setpoint N M1ref being sent to the backup regulation system of the heat engine, the instantaneous speed N M1m of the heat engine is measured and it is compared with the rotational speed setpoint N M1ref :

if N M1ref <N M1m , an auxiliary fuel flow QCarbAux* is controlled such that it reduces the fuel flow QCarb injected into the combustion chamber of the heat engine, thereby reducing the power P M1 of the heat engine;

if N M1ref >N M1m , an auxiliary fuel flow QCarbAux* is controlled such that it increases the fuel flow QCarb injected into the combustion chamber of the heat engine, thereby increasing the power P M1 of the heat engine; and

if N M1ref =N M1m , the flow command QCarbAux* is kept constant;

and simultaneously, the instantaneous power P M2m of the electric motor is compared with the reference power P M2ref , and

if P M2m <P M2ref , the rotational speed setpoint of the heat engine N M1ref is reduced;

if P M2m >P M2ref , the rotational speed setpoint of the heat engine N M1ref is raised.

4 . A control device for regulating the rotational speed (N p ) of a propulsion device of a hybrid propulsion unit for an aircraft in the event of failure of the main regulation system of the heat engine of the hybrid propulsion unit, the hybrid propulsion unit comprising:

the propulsion device and a main gearbox, configured to drive the propulsion device;

the heat engine and at least one electric motor, mounted in parallel on the main gearbox, the heat engine being provided with a fuel circuit configured to transfer fuel into a combustion chamber of the heat engine;

a main regulation system of the heat engine, configured to regulate the rotational speed of the heat engine;

a backup regulation system of the heat engine, configured to regulate the rotational speed of the heat engine when the main regulation system fails;

a regulation system of the electric motor, configured to regulate the rotational speed of the electric motor;

a control system of the aircraft, configured to send a speed or power setpoint to each of the regulation systems of the heat engine and of the electric motor;

wherein, when the main regulation system of the heat engine fails and said system is locked to a fuel flow command QCarbP*, the control device is configured to:

send a speed setpoint N M2ref to the regulation system of the electric motor, so that the regulation system of the electric motor sends a power command P M2* to the electric motor, whereby an instantaneous power P M2m of the electric motor is obtained;

simultaneously, send a rotational speed or power setpoint to the backup regulation system of the heat engine, so that the backup regulation system sends a fuel flow command QCarbAux* to the fuel circuit of the heat engine, the command QCarbAux* is selected so as to vary the fuel flow QCarb injected into the combustion chamber of the engine depending on whether it is desired to increase or decrease the power P M1 of the heat engine; and

control the rotational speed (N p ) of a propulsion device by controlling an auxiliary fuel flow QCarbAux* and the fuel flow QCarb injected into a combustion chamber of the heat engine.

5 . The control device according to claim 4 , wherein, a reference power setpoint of the electric motor P M2ref* being sent to the backup regulation system of the heat engine, the fuel flow command QCarbAux* is selected by comparing the instantaneous power P M2m of the electric motor with the reference power P M2ref , and wherein the control device is configured to:

if P M2m <P M2ref , control an auxiliary fuel flow QCarbAux* such that it reduces the fuel flow QCarb injected into the combustion chamber of the heat engine, thereby reducing the power P M1 of the heat engine;

if P M2m >P M2ref , control an auxiliary fuel flow QCarbAux* such that it increases the fuel flow QCarb injected into the combustion chamber of the heat engine, thereby increasing the power P M1 of the heat engine;

if P M2m =P M2ref , keep the flow command QCarbAux* constant.

6 . The control device according to claim 4 , wherein a rotational speed setpoint N M1ref being sent to the backup regulation system of the heat engine, the instantaneous speed N M1m of the heat engine is measured and it is compared with the rotational speed setpoint N M1ref and wherein the control device is configured to:

if N M1ref <N M1m , control an auxiliary fuel flow QCarbAux* such that it reduces the fuel flow QCarb injected into the combustion chamber of the heat engine, thereby reducing the power P M1 of the heat engine;

if N M1ref >N M1m , control an auxiliary fuel flow QCarbAux* such that it increases the fuel flow QCarb injected into the combustion chamber of the heat engine, thereby increasing the power P M1 of the heat engine; and

if N M1ref =N M1m , keep the flow command QCarbAux* constant;

and simultaneously, compare the instantaneous power P M2m of the electric motor with the reference power P M2ref , and

if P M2m <P M2ref , reduce the rotational speed setpoint of the heat engine N M1ref ;

if P M2m >P M2ref , raise the rotational speed setpoint of the heat engine N M1ref .

7 . A non-transitory computer readable medium for storing a computer program comprising instructions which, when the program is executed by a computer, cause the computer to perform the steps of:

sending a speed setpoint N M2ref to an regulation system of an electric motor, so that the regulation system of the electric motor sends a power command P M2* to the electric motor, whereby an instantaneous power P M2m of the electric motor is obtained;

simultaneously, sending a rotational speed or power setpoint to a backup regulation system of the heat engine, so that the backup regulation system sends a fuel flow command QCarbAux* to a fuel circuit of the heat engine, the command QCarbAux* is selected so as to vary the fuel flow QCarb injected into a combustion chamber of the heat engine depending on whether it is desired to vary the power P M1 of the heat engine; and

controlling the rotational speed (N p ) of a propulsion device by controlling an auxiliary fuel flow QCarbAux* and the fuel flow QCarb injected into a combustion chamber of the heat engine.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (11)