Browsing by Subject "switching line design"

Now showing 1 - 1 of 1

Access status: Open Access ,
Variable structure control of second order system with acceleration constraint
(Wydawnictwa AGH, 2009) Nowacka-Leverton, Aleksandra; Bartoszewicz, Andrzej
The paper presents a new sliding mode control (SMC) method for the second order system subject to acceleration constraint. The proposed method employs a time-varying switching line which initially passes through the representative point, specified by the initial conditions of the system, in the error state space. Afterwards the line moves smoothly, with a constant velocity and a constant angle of inclination to the origin of the error state space and then, having reached the origin it stops moving and remains fixed. Thus the proposed control algorithm eliminates the reaching phase and forces the representative point of the system always to stay on the switching line. Consequently, insensitivity of the system with respect to external disturbances and model uncertainties is guaranteed from the very beginning of the proposed control action. Parameters of the switching line are selected to minimize two control quality criteria - the integral absolute error (IAE) and the integral of the time multiplied by the absolute error (ITAE) - without violating the system acceleration constraint. Furthermore, the switching line is selected in such a way that the tracking error converges to zero monotonically, without overshoots or oscillations. The proposed method is verified and illustrated by a simulation example.