Unknown input reconstruction for LPV systems

Journal article, 2010

Detection and invariant subspaces of unknown inputs' signals for linear parameter-varying systems are examined in the paper. For a class of nonlinear system like this, the effect of unmeasured signals in parameter-varying measurement equation at the plant output is investigated. The main contributions of the paper are the parameter-varying extension of the pseudo-actuation of the possible and generic unknown sensor signal and the proposition of parameter-dependent similarity transformation. The general parameter-varying measurement equation is casted into a parameter-independent form by the similarity transformation, if any. Moreover, it showed that the nonlinear state transformation does not modify the output subspace spanned by the equivalent pseudo-actuator directions.