Design a novel digital sliding mode predictive control for buck converter

ABSTRACT

In this article, a new discrete-time sliding mode predictive control (DSMPC) with a PID sliding function is proposed for synchronous DC–DC buck converter, and its stability analysis is reported. The model predictive control, along with digital sliding mode control (DSMC), is able to further reducing the chattering phenomenon, steady-state error, overshoot and undershoot. The proposed control implementation only requires output error voltage evaluation. The effectiveness of the proposed DSMPC is proved through simulation results executed by the MATLAB/SIMULINK software. These results demonstrate its superior performance to DSMC. In other words, it represents a significant reduction of the chattering, overshoot and undershoots of output voltage response by an optimised control law during load and line variations. The proposed DSMPC almost overcomes the steady-state error (0.02%) and decreases the ripple value to about 0.2%. The overshoot and undershoot are 1.5% and 1%, respectively. Moreover, when the input voltage is changed by 26%, there is approximately no overshoot and undershoot. Also, some experimental results are presented to further illustrate the effectiveness of the proposed system. Experimental studies have been performed using a Spartan-6 field programmable gate array platform by Xilinx for the implementation of the digital control and relevant logic.

KEYWORDS:

• Digital sliding mode control
• predictive control
• synchronous DC–DC buck converter
• variable structure system
• dynamic performance

Disclosure statement

No potential conflict of interest was reported by the author(s).