Author_Institution :
Dept. of Electr. Eng., Yuan Ze Univ., Chung Li, Taiwan
Abstract :
Presents a design for nonlinear decoupled control of a linear induction motor (LIM) servo-drive. An ideal feedback linearisation control (IFLC) system is first adopted in order to decouple the thrust force and the flux amplitude of the LIM. However, the control performance of the LIM is influenced seriously by the uncertainties of the plant, such as electrical and mechanical parameter variation, external force disturbance and unmodelled dynamics in practical applications. Hence, to increase the robustness of the LIM drive for high-performance applications, a sliding-mode feedback linearisation control (SMFLC) system, that comprises a sliding-mode flux controller and a sliding-mode position controller, is proposed to decouple the thrust force and the flux amplitude of the LIM. The control laws of the SMFLC system are derived in the sense of the Lyapunov stability theorem, such that the asymptotic stability of the control system can be guaranteed under the occurrence of system uncertainties. Moreover, to relax the requirement of the secondary flux in the SMFLC system, an adaptive flux observer is proposed to estimate the secondary flux, considering all possible uncertainty in practical applications. In addition, the effectiveness of the proposed control scheme is verified by some simulated results
Keywords :
Lyapunov methods; asymptotic stability; feedback; induction motor drives; linear induction motors; linearisation techniques; machine control; nonlinear control systems; observers; position control; robust control; servomotors; uncertain systems; variable structure systems; Lyapunov stability theorem; adaptive flux observer; control performance; flux amplitude; ideal feedback linearisation control system; linear induction motor servo-drive; nonlinear decoupled control; robustness; secondary flux; sliding-mode flux controller; sliding-mode position controller; sliding-mode technique; thrust force;
