Active Control of Shaft Torsional Vibration with a Dynamic Torque Actuator

Multi-harmonic fluctuations from the output torque of an engine, propeller, or other power source constitute the main source of torsional vibration of a shafting system, and stimulate other coupled vibrations. This paper introduces a new method to address torsional vibrations of shafting systems based on line spectrum active control. A multi-body dynamic analysis model is used to reveal the coupling characteristics of torsional vibration and vibration in other directions. In addition, a new cross-coupled multi-channel line spectrum active control algorithm is proposed alongside a new type of torque actuator where the internal electromagnetic structure contains a rotating stator and rotor. These components are connected with springs, and the whole assembly can rotate with the shafting. The dynamic torque is issued according to the command of the active control system in order to suppress the torque fluctuation due to the power sources, which in turn greatly reduces the torsional vibration of the shafting.