ON-LINE PARAMETER ESTIMATION VIA ALGEBRAIC METHOD: AN EXPERIMENTAL ILLUSTRATION

This article presents an algebraic online parameters estimation method for linear time invariant (LTI) systems, subject to polynomial perturbations. Particular attention is given to practical implementation. The estimator may be expressed as a simple finite impluse response (FIR) filter, which is advantageous for online application, since the coefficients may be computed offline. The robustification against possible singularities is shown, the approach has the advantage to eliminate singularities that may occur in the experimental identification. This algorithm is illustrated experimentally on a permanent magnet stepper motor (PMSM) and a magnetic bearing for which parametric estimation is known to be a difficult task. The parameters to be estimated are sometimes measurable with difficulty and may vary slightly over time.