Design of novel two-layered fuzzy logic controller for plants with time-varying dead-zone and saturation characteristics

Article type: Research Article

Authors: Oh, Seok-Yong | Park, Dong-Jo^;

Affiliations: Electronics and Telecommunications Research Institute (ETRI), Taejon, South Korea Korea Advanced Institute of Science and Technology (KAIST), 373‐1 Kusong‐dong, Yusong‐gu, Taejon 305‐701, South Korea

Note: [] Corresponding author. Tel. +82 42 869 3438; Fax: +82 42 869 3410; E‐mail: djpark@eekaist.kaist.ac.kr.

Abstract: A novel two‐layered fuzzy logic controller (FLC) is designed for plants with unknown and/or time‐varying dead‐zone and saturation characteristics in their actuators. A dead‐zone inverse to compensate for the dead‐zone in the actuator is implemented by an inner‐layered fuzzy logic controller. Automatically adjusted control resolution plays a key role as a fuzzy dead‐zone inverse. An outer‐layered controller compensates for the saturation using the integral anti‐windup circuit, once the dead‐zone is compensated by the inner‐layered fuzzy logic controller. The developed fuzzy logic controller is applied to the plants with unknown dead‐zone and saturation characteristics for ensuring their effectiveness even though the dead‐zone characteristics are time‐varying.

Journal: Journal of Intelligent and Fuzzy Systems, vol. 8, no. 3, pp. 173-190, 2000