An Algebraic Approach for Identification of Linear Systems with Fractional Derivatives

Identification of fractional order systems is considered from an algebraic point of view. It allows for a simultaneous estimation of model parameters and fractional (or integer) orders from input and output data. It is exact in that no approximations are required. Using Mikusinski’s operational calculus, algebraic manipulations are performed on the operational representation of the system. The unknown parameters and (fractional) orders are calculated solely from convolutions of known signals. A generalized Voigt model describing a viscoelastic material is used to illustrate the approach.