Design and analysis of state-constrained nonlinear finite-time control algorithm with application to buck converter

This paper proposes a double closed loop current-constrained finite-time controller for the buck converter circuit under current constraint. Firstly, the controller consists of an outer loop controller and an inner loop controller. The outer loop controller is dedicated to voltage tracking and enhances the speed of voltage convergence. Meanwhile, the inner loop controller employs the Barrier Lyapunov Function to ensure the current remains within a safe range. Secondly, homogeneous system method is used to demonstrate the finite-time stability of the double closed loop system. Finally, simulations and experiments validate the effectiveness and superiority of the proposed algorithm in the start-up stage and load mutation stage.