CONTINUOUS FINITE-TIME SLIDING MODE CONTROL FOR UNCERTAIN NONLINEAR SYSTEMS WITH APPLICATIONS TO DC-DC BUCK CONVERTERS

This paper investigates the continuous finite-time control problem of high-order uncertain nonlinear systems with mismatched disturbances through the terminal sliding mode control method. By constructing a novel dynamic terminal sliding manifold based on the disturbance estimations of high-order sliding mode observers, a continuous finite-time terminal sliding mode control method is developed to counteract mismatched disturbances. To avoid discontinuous control action, the switching terms of a dynamic terminal sliding manifold are designed to appear only in the derivative term of the control variable. To validate its effectiveness, the proposed control method is applied to a DC-DC buck converter system. The experimental results show the proposed method exhibits better control performance than a chattering free controller, such as mismatched disturbances rejection and smaller steady-state fluctuations.