STABILITY ANALYSIS OF FUZZY CONTROL SYSTEMS:AN OVERVIEW
【摘要】：正Fuzzy control has been successfully applied to many commercial products and industrial systems, where: 1) no accurate mathematical models of the systems under control are available, and 2) human experts are available to provide linguistic fuzzy control rules or linguistic fuzzy descriptions about the systems. In the early days of fuzzy control theory and applications, fuzzy controllers were designed in a heuristic fashion and no stability analysis were given. This results in a misunderstanding that there is no stability analysis for fuzzy control systems. The situation has been changing in recent years, as more rigorous stability analysis is appearing in the literature. This presentation provides an overview of some typical results for stability analysis of fuzzy control systems. We consider three cases: 1) the plant is linear, 2) the plant is nonlinear, and 3) the plant is modeled by fuzzy models. For the first case, we show how to use the results in classical control theory to design stable fuzzy controllers. For the second case, we present two approaches - sliding control and supervisory control - to designing stable fuzzy controllers. For the third case, we show how fuzzy controllers can be designed for fuzzy models to guarantee closed-loop stability. The objective of the presentation is to show that good stability results for fuzzy control systems do exist and they can be used to design fuzzy control systems with guaranteed stability.