Method and system for controlling at least one actuator of the cowlings of a turbojet engine thrust inverter
The invention relates to a control system for at least one actuator ( 6 ) for the cowlings of a thrust inverter in a turbojet engine, that comprises an assembly of actuation and/or control components. A control means ( 9 ) is provided for detecting the failure of an actuation and/or control component ( 7, 16, 13 ), for determining the blocking or non-blocking character of the failure for the system operation and, in case of a non-blocking failure, for switching from a nominal operation mode to a failure-adaptation operation mode in which the failure of the actuation and/or control component ( 7, 16, 13 ) is compensated at least partially by a modified instruction of the other actuation and/or control components ( 7, 16, 13 ).
1. A system for controlling at least one actuator of cowlings of a thrust reverser for a turbojet engine, said system comprising a set of actuating and/or checking components of the at least one actuator, the set of actuating and/or checking components comprising:
at least one electric motor to drive the at least one actuator;
control means for controlling the at least one actuator and the at least one electric motor;
means of communication between the control means and an aircraft control system; and
at least one position sensor sensing a position of the cowlings of the thrust reverser or a position of the at least one actuator used to provide feedback control of the at least one actuator,
wherein the control means are configured to detect a failure of a component of the set of actuating and/or control components, and the control means are configured to determine whether the failure of the component does or does not disable the operation of the system,
wherein if the failure of the component is not a disabling one, the control means are configured to switch from a normal mode of the operation of the system to failure accommodating modes of the operation of the system, and the failure-accommodating modes comprise first, second and third failure-accommodating modes in which the failure of said at least one position sensor, said at least one electric motor, and an electrical power supply to the system or of a power stage of the system is at least partially compensated by a modified command of other component of the set, so that when the at least one position sensor is in failure but does not disable the operation of the system, the control means are configured to carry out the first failure accommodating mode in which a modified command lowers a torque and/or a speed of the at least one electric motor, and detects an end of travel of the cowling through an increase in the motor torque and/or an increase in the motor current,
wherein in an event of a partial failure of the electrical power supply to the system or of the power stage of the system, the control means are configured to carry out the second failure-accommodating mode in which a modified command of the at least one electric motor reduces motor current below a limiting current liable to cause a break in the electrical power supply,
wherein in an event of a partial failure of said at least one electric motor, the control means are configure to carry out the third failure-accommodating mode in which the controller deactivates a motor brake and detects a direction of travel of said at least one actuator and/or of the cowls under an effect of an aerodynamic forces.
2. The system as claimed in claim 1 , wherein in an event of a failure of the at least one electric motor, the control means are configured to carry out a modified command in order to open the cowlings of the thrust reverser, the modified command comprising unlocking at least one latch of the cowlings.
3. The system as claimed in claim 2 , wherein the control means are configured to detect direction of travel of the at least one actuator and/or the cowlings of the thrust reverser under effect of aerodynamic forces in order to block movement in a direction of closure by a motor brake.
4. The system as claimed in claim 1 , further comprising warning means for alerting a user when the system is in failure-accommodating mode of operation.
5. A method for controlling a system for controlling at least one actuator of cowlings of a thrust reverser for a turbojet engine according to claim 1 , the method comprising:
detecting a failure of a component of the set of actuating and/or checking components of the actuator control system comprising the at least one position sensor configured to sense the position of a reverser cowling or the position of an actuator of the cowlings of a thrust reverser;
determining whether the failure of the component of the set is disabling or not disabling the operation of the system;
choosing a failure-accommodating mode when the failure is not disabling the operation of the system, so that when the at least one position sensor is in failure, the control means configured to carry out a modified command by lowering a torque and/or a speed of the at least one electric motor; and
applying the chosen failure-accommodating mode.
6. The method as claimed in claim 5 , further comprising alerting a user when the system is in the failure-accommodating mode.