2006 Volume 19 Issue 11 Pages 413-417
A design procedure is proposed for digital repetitive controllers satisfying (i) asymptotic rejection of a class of periodic disturbances and (ii) a sampled-data H∞ norm specification. The synthesis problem is formulated by extending the step disturbance rejection problem. A necessary condition for the periodic disturbance so that the synthesis problem has a solution is derived. The synthesis problem is finally reduced to a sampled-data H∞ control problem with a design parameter which can be used for adjusting the performance of the periodic disturbance rejection. The effectiveness of the proposed method is confirmed by a numerical example.