Parameter Estimation of Linear Systems Based on Walsh Series

This paper presents a frequency domain based methodology using Walsh series, the method can be used to make a parameter identification of time-varying linear systems and time invariant linear systems. The methodology takes advantages of the operational properties available to most orthogonal series expression, i.e. integration, differentiation, product and coefficient matrices. Properties of Walsh series are first briefly presented and the operational matrices are utilized to reduce the dynamical equations of a linear varying/invariant system to a set of simultaneous linear algebraic equation, these equations can be solved using a pseudoinverse to obtain the unknown parameters. The method presented in this paper was proved satisfactory to estimate parameters in two applications: DC motor and DC-DC converter.