Design of torsional oscillation observer with quantization effects

A torsional oscillation observer based on the general observer was discussed to estimate the speed of the turbine generator. The dynamic characteristics of standard Luenberger observer with quantization effects were studied by Lyapunov stability criterion. It is concluded that the state estimate error can not asymptotically converge to zero in-the-large in presence of quantization effects. By modeling the quantizers as deterministic memoryless nonlinearities, a sufficient condition for the asymptotical convergence of observer was derived. A new torsional oscillation observer was introduced which can guarantee the asymptotic convergence of tracking error if the system matrix is Hurwiz.