Adaptive compensation strategy for the tracking/rejection of signals with time-varying frequency in digital repetitive control systems
✍ Scribed by Josep M. Olm; Germán A. Ramos; Ramon Costa-Castelló
- Publisher
- Elsevier Science
- Year
- 2010
- Tongue
- English
- Weight
- 775 KB
- Volume
- 20
- Category
- Article
- ISSN
- 0959-1524
No coin nor oath required. For personal study only.
✦ Synopsis
Digital repetitive control is a technique which allows to track periodic references and/or reject periodic disturbances. Repetitive controllers are usually designed assuming a fixed frequency for the signals to be tracked/rejected, its main drawback being a dramatic performance decay when this frequency varies. A common approach to overcome this problem consists of an adaptive change of the sampling time according to reference/disturbance period variations. However, the sampling period adaptation implies structural changes that may degrade the closed-loop time response. This article presents a design strategy which allows to compensate for the effect of non-uniform sampling and forces the closed-loop behavior to coincide with that of the system operating under an a priori selected nominal sampling period. The stability of the overall closed-loop system is also analyzed. Experimental results obtained from a mechatronic plant model validate the proposal.