Patent ID: 11939072
Assignee: AIRBUS HELICOPTERS
Field: Transport (Mechanical engineering)
Classification: CPC B  Y | IPC B

Claim 10:
11. A method of optimizing the noise generated by a rotorcraft on the ground, the rotorcraft including a hybrid power plant provided with an engine and with an electric machine, a rotor driven in rotation with mechanical power from the hybrid power plant, and an electrical energy source electrically powering the electric machine via an electrical network, the method comprising:
performing with a detector device a first monitoring step for monitoring whether the rotorcraft is on the ground;
detecting by the detector device from the first monitoring step that the rotorcraft is on the ground;
performing with a control unit a second monitoring step for monitoring whether the engine is in the started or on state or in the stopped or off state, and for monitoring a speed of the engine;
detecting by the control unit from the second monitoring step that the engine is in the on state;
performing with a control device a third monitoring step for monitoring whether the electric machine is in the on state or in the off state, and for monitoring a speed of the electric machine;
in response to the rotorcraft being on the ground and the engine being in the on state, performing with the control unit a first control step for controlling the engine so as to lower the speed of the engine until the speed of the engine reaches a predetermined speed referred to as a silent speed, the silent speed being either an idling speed of the engine or a reduced speed of the engine making it possible to reduce the noise generated by the engine, the reduced speed being a speed of the engine that keeps the engine in the on state; and
in response to the speed of the engine being lowered to reach the silent speed, performing with the control device a second control step for controlling the electric machine so that the electric machine delivers mechanical power supplementary to any mechanical power delivered by the engine for driving the rotor in rotation while complying with a setpoint speed of rotation of the rotor.