Parameter estimation and pole-placement control of time-varying plants.

The pole placement and adaptive pole placement control problem of linear time-varying plants with smooth parameters is considered. A controller structure is proposed which guarantees the closed-loop stability and meets the control objective exactly independent of the speed of variation of the plant parameters. An adaptive estimator is designed that can use any available a priori knowledge about the structure of the plant parameter estimates. Using the certainty equivalence principle, an indirect adaptive pole placement scheme is developed for time-varying plants that guarantees the closed-loop stability, provided that only the variation of the unstructured (unknown) part of the parameters is slow, while the overall plant may be fast time-varying.