Abstract:

In this paper, the robust ripple-free tracking and disturbance rejection problem is solved for multirate sampled-data systems whose matrices are assumed to depend on some ``physical'' parameters. Making use of a hybrid control system structure, including a continuous-time internal model of the exogenous signals and a periodic discrete-time subcompensator, a ripple-free null steady-state error response is obtained in a neighbourhood of the nominal ``physical'' parameters of the plant, and a ripple-free dead-beat error response at the nominal ones.