Adaptive integral type-terminal sliding mode control for PEMFC air supply system using time delay estimation algorithm

This paper proposes a new cascaded adaptive integral type-terminal sliding mode control based on time delay estimation algorithm (cascaded-AITSMC-TDE) for the proton exchange membrane fuel cell (PEMFC) system with unknown uncertainties. The proposed cascaded-AITSMC-TDE scheme is composed of two components: time delay estimation (TDE) technique and cascaded-adaptive integral type-terminal sliding mode control (AITSMC). The TDE is employed to approximate unknown uncertain dynamic. The cascaded-AITSMC is integrated with TDE to control oxygen excess ratio (stoichiometry) and air flow rate keeping a proper system performance under load disturbance, avoiding the oxygen starvation. The stability of the proposed cascaded-AITSMC-TDE via closed-loop system is verified by Lyapunov approach. In order to validate the effectiveness and robustness of the proposed cascaded-AITSMC-TDE, a comparative study with a single loop AITSMC, cascaded integral type-terminal sliding mode control (cascaded-ITSMC) and cascaded integral sliding mode based-time delay estimation (cascaded-ISMC-TDE) is carried out, and the corresponding simulation results exhibit that the proposed controller provides fast convergence of tracking trajectories with less fluctuations.