Torsional mode damping controller

A torsional mode damping controller for an electro-mechanical system in which power electronics provide electrical power to drive an electrical motor, and in which plural rotating masses, including a rotor of the electrical motor, are mechanically coupled to transmit torque therebetween, the controller modifying the electrical power provided to the electrical motor to provide active damping control of torsional vibration in the rotating masses, wherein the controller is configured to:

• receive a measurement of a rotational speed of the rotating masses ωm and an estimate or a measurement of a torque transmitted between the rotating masses Tsh;
• based on the received transmitted torque Tsh, generate a compensating torque to suppress vibration Tcom by applying a filter to the received transmitted torque Tsh, the filter being based on plural tunable parameters including a tuning gain K, a cut-off frequency ωn and a resonant damping ratio ζ, the filter providing a phase lead which, at a natural resonant frequency for torsional vibration in the rotating masses, is at least 70 degrees;
• based on the received rotational speed ωm and the compensating torque Tcom, generate an electromagnetic torque modification signal Tmodi;
• and
• modify the electrical power provided to the electrical motor based on the electromagnetic torque modification signal Tmodi.