可變結構與模糊邏輯控制做非線性動態系統的穩健控制

Abstract

近幾年來，對於非線性動態系統的穩健控制已經有許多的努力與成 果，而在本論文中提出另一種以可變順滑平面的順滑模態控制結合模糊邏 輯法則而成的穩健控制。由於順滑模態控制在控制器的求得上，依賴著複 雜的運算，所以我們以較簡單而且不需複雜計算的模糊邏輯法則來替代。 其次，提出了一套以可變順滑平面的模糊順滑模態控制，其中以變化順滑 平面的方法做控制，以改善以傳統順滑模態控制（固定一順滑平面）在暫 態的效果。本方法的特點包括：減少順滑模態控制中的切跳現象，提供一 個簡單的控制器設計過程，有效抗距系統參數變化和外來干擾以及對於暫 態和穩態時的改善。 Robust control of nonlinear dynamic systems has been studied for years. Inthis dissertation, a new robust controller design of nonlinear dynamic systemsis proposed by combining with sliding mode control, and fuzzy logic. Essentially, the sliding mode control uses discontinuous control action to drive state trajectories toward a specific hyperplane in the state space, and to maintain the state trajectories sliding on the specific hyperplane. This principle provides a guideline to design a fuzzy controller. In order to improve traditional sliding mode control with unique sliding surface in transient response, a sliding mode control with variable sliding surface is proposed in this thesis. Attractive features of the proposed method include a systematic procedure of controller design, a reduction in chattering, transient and steady-state response are improved, robustness against model uncertainties and external disturbances. Three numerical examples are given to demonstrate the effectiveness of the proposed method.