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In this dissertation, a control configuration for multivariable
systems with periodic exogenous signals is proposed. The plant
is assumed to be linear time-invarient,minimum phase,
nonsingular , strictly proper and may be unstable. The
exogenous siganls considered for different channels may have
different periods and at least be piecewise-continuous.
Combining Zames'' theorem with the repetitive control, a design
algorithm to make the control system achieve closed-loop
stabili- ty, input-output decoupling and a prespecified
sensitivity bound is proposed. In this study the tracking
accuracy is required to satisfy specification defined in the
sense of relative steady state error. The sensitivity
specification includes a lower bound within a bandwidth and an
upper bound for higher frequency range. A control system
configuration is established using pure repetitive control
structure associated with a low pass filter. The stability is
guaranteed using regeneration spectrum analysis. The effect of
such a repetitive controller on sensitivity is derived. The
design algorithm is verified by an illustrative example.
Comparing with other design methodology, the proposed algorithm
produces a less conservative and much simpler controller.
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