Extended state observer-based nonsingular terminal sliding mode controller for a DC-DC buck converter with disturbances: theoretical analysis and experimental verification

This paper develops a nonsingular terminal sliding mode controller (NTSMC) based on extended state observer (ESO) for buck converter subject to load disturbances and input voltage variations. First, novel modeling method is developed transform the matched mismatched caused by resistance variations into uniform total disturbance. Second, an ESO established estimate differential of output Third, NTSMC designed achieve faster tracking speed better accuracy around expected voltage. In addition, theoretical stability proposed analyzed Lyapunov criterion. Finally, both simulation experimental results show that NTSMC-ESO with can attenuate variation effectively has disturbance rejection ability than reduced-order controller.Abbreviations: ADRC: active control; ESO: observer; NTSMC: RESO: SMC: control