Generalized-extended-state-observer-based Sliding-mode Control for Buck Converter Systems

This paper presents a generalized-extended-state-observer (GESO)-based sliding-mode control (SMC) method to deal with mismatched parameter uncertainty and reference-input mutation for a class of DC-DC buck converter systems (BCS). First, a GESO is designed to estimate the total disturbance together with the system state. Then, by choosing an appropriate disturbance-compensation gain, a composite SMC law is designed to attenuate the influence of the parameter uncertainty and reference input mutation on the system output. Both the stability criterion and deign procedure of the system are given. Finally, simulation results show that the designed GESO-based SMC system for the DC-DC BCS is robustly stable and achieves both satisfactory transient and steady-state performance. Comparisons demonstrate that the proposed method provides better transient and steady-state performance for both disturbance rejection and tracking control than either conventional SMC or ESO-based control approach does.