Application of Power Electronics for Damping of Torsional Vibrations

Torsional vibrations occur in mechanical shafts whenever they couple rotating masses. Especially shaft assemblies with large inertias and long shafts, e.g. in turbo- generating sets of power plants or in drives, these oscillations can be a major problem due to the weak natural damping and the sharp resonance points of these systems. It is impossible to obtain a desirable damping of these torsional vibrations by means of a mechanical method. However, by using a power electronics converter and an inductive or capacitive energy storage, an electrical method can be used to implement an active damping. The following paper illustrates the needed configuration and the necessary controls of the required converters for damping torsional vibrations.