Torque control methods for active damping of vibrations in drive systems of wind turbines

Within the scope of this paper, a number of speed and torque control methods and their ability to specifically influence vibrations and the load spectrum is introduced and compared. The design of two control concepts (speed and torque) for an active vibration damping - based on the principle of the PID state control - is presented and the challenges with respect to the choice of the layout method (pole placement and LQR method) and recording of the states (which are hardly measurable or only with great efforts) (layout of a Kalman observer), as well as the advantages and disadvantages during operation are discussed. A comparison is made with a standard PID control method and the test results are discussed with regard to the manipulated variable demand and the ability of an active minimization of oscillations in the drive train.