Real Time Performance Comparison of Buck Converter Circuit Controlled By Discrete Time PID, LQR and SMC Controllers in Continuous-Current Mode

In this study, a DC-DC buck converter circuit which is used to get direct voltage by decreasing the source voltage is researched. Firstly mathematical model for a DC-DC buck converter circuit is obtained and critical inductance value is calculated to make it work in continuous current mode. Then for controlling a DC-DC buck converter, three different controllers in discrete time (sliding mode control, proportional–integral–derivative controller and linear quadratic regulator) are designed. Finally, the performance of these controllers according to changing in the form of step function for input voltage, reference voltage and load conditions are examined and compared with real time studies. According to obtained results, a DC-DC buck converter circuit controlled by sliding mode controller has shown a better performance compared to the other controllers.