Analysis and synthesis of minimum phase nonlinear SISO-systems under the action of external mismatched disturbances

For non-minimum phase systems with single-input and single-output the structure of an equivalent form of input-output with the smooth, mismatched disturbances is formalized. On the basis of this form the basic law of combined control providing the asymptotic stabilization of the tracking error is synthesized. Unlike the traditional approach, which requires generators of given signal and external disturbances, for a comprehensive estimation of external signals and their derivatives the observer on sliding modes is used. Conditions of physical realizability of invariant tracking system for the case when direct measurements are only available for output (adjustable) variable and setting signal is formalized.