According to the systems like Buck converters which has the characteristics of strong nonlinear and stochastic load disturbance，and considering engineering demand of digital control implementation, a discrete-time terminal sliding mode control strategy was proposed based on conventional terminal sliding mode control. The stability of the system, the output tracking errors under the discrete-time terminal sliding mode controller and discrete-time linear sliding mode controller were analyzed. Finally, the proposed method was applied to the output voltage control of Buck converter and simulation was done. The steady-state error of the output, the settling time and the controller output chattering under the above two discrete-time controllers were compared. The simulation results showed that discrete-time terminal sliding mode control improved dynamic and static characteristics and robustness performance of the system effectively.
