METHOD FOR CONTROLLING A ROTATIONAL SPEED OF AN OUTPUT SHAFT OF A PROPULSION UNIT

A method for controlling a rotational speed of an output shaft of a propulsion unit. The method includes determining a speed setpoint value, indicative of a rotational speed setpoint for the output shaft, and an actual speed value, indicative of an actual rotational speed of the output shaft, determining an acceleration value using an acceleration value determination procedure comprising employing an acceleration conversion function that uses the speed setpoint value, the actual speed value and an acceleration setting member as inputs and which produces a resulting value to be used for determining the acceleration value, the acceleration conversion function being such that different resulting values can be obtained for the same set of the speed setpoint value and the actual speed value but for different choices of the acceleration setting member, determining a torque request value using a torque conversion operation that uses the acceleration value, and controlling the propulsion unit using the torque request value.