Ripple attenuation in digital repetitive control systems

Abstract

Ripple phenomena in digital repetitive control systems are investigated based on a steady-state analysis. It is shown that the larger ripple is mainly caused by the larger steady-state control input. The authors introduce an index for the level of the ripple related to the level of the steady-state control input. Design methods using generalized hold function and asynchronized sampling are proposed for the attenuation of the ripple. Numerical examples show the usefulness of the proposed methods.<>