tailieunhanh - Hedge algebras gain scheduling of PID controller

In this paper, the author proposes a method modified on-line the parameters of the PID controller based on combining the hedge algebras control and model reference system. This proposal has inherited the adaption of hedge algebras control deal with the uncertain systems or nonlinear systems and the sustainability of model reference system for load disturbances and measurement noise. | Nghiên cứu khoa học công nghệ HEDGE ALGEBRAS GAIN SCHEDULING OF PID CONTROLLER Pham Van Thiem Pham Duy Khanh Nguyen Hoang Viet Abstract In this paper the author proposes a method modified on-line the parameters of the PID controller based on combining the hedge algebras control and model reference system. This proposal has inherited the adaption of hedge algebras control deal with the uncertain systems or nonlinear systems and the sustainability of model reference system for load disturbances and measurement noise. In addition the parameters of fuzziness measure are taken into account as design variables which is determined by the genetic algorithm. Experiment results of aerodynamic lift system are provided to illustrate the effectiveness of the theoretically analyzed results. Keywords PID controller Hegde algebras Aerodynamic lift system Arduino mega. 1. INTRODUCTION It is well known that despite many sophisticated control theories and techniques that have been devised in last decades proportional-integral-derivative PID controllers are still the most adopted in practical case. In fact due to their simple structure PID controllers are relatively easy to tune and their use is well understood by a great majority of industrial practitioners and automatic control designers. Several methods are available for tuning the parameters of the PID controller such as Ziegler-Nichols Cohen-Coon and some software 1 . Unfortunately real systems have in general significant characteristics such as high-order nonlinearities deal-time etc. and they can be affect by noise load disturbances and other environmental conditions that cause parameters variations and sudden modification of model structure. In this context the tuning the controller parameters is a crucial issue. For this reason many tuning formulate have been proposed in the literature 2 . Hedge algebras were developed by Nguyen and Wechler 1990 to model the orderbased semantics of the terms in term-domains of linguistic .