Summary: | 碩士 === 國立中興大學 === 電機工程學系 === 88 === This thesis presents a post-filtering approach to variable structure output feedback control for a single-input system. Given a sliding surface S(x)=0, designed through standard procedures with full state accessibility, a dynamic filter for the output variable y is employed to synthesize S to be used for the variable structure control law. This method avoids using observers for state reconstruction and, hence, requires only partial information of system parameters.
Realization of the post-filter is divided into two cases. With system relative degree equal to one, realization can be accomplished by using the discretization technique. If the relative degree exceeds one, discretization for inverse transfer function of the post-filter is recommended. Another way is to construct a sliding surface S with the same relative degree as y. In this case, an auxiliary output function w is created as the new sliding surface that has relative degree one. A forth order mechanical suspension system is taken as example to demonstrate the design procedure.
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