Periodic Control of Linear Time-invariant Systems - A Critical Point of View

Abstract

The use of periodic control in various forms has a long history in the control literature. It has been argued that a periodic feedback gain or controller when applied to an LTI system can accomplish more than their time invariant counterparts. Some authors, however, did express concerns that practical problems may arise but the source of these difficulties has not been made explicit. In this paper, by thoroughly analyzing an example used in the literature, we show two critical problems periodic controllers suffer from: They generate high frequency components and they are sensitive to the controlled system high frequency behavior.