A multi-surface sliding-mode extremum seeking controller for alternator maximum power point tracking

Power maximization is of great interest in energy conversion systems including renewable sources and alternators used in automotive systems. This paper presents a multi-surface sliding-mode extremum seeking controller for achieving Maximum Power Point Tracking (MPPT) for energy conversion involving a Lundell alternator. The proposed multi-surface sliding scheme results in smooth and fast convergence to the extremum point while achieving robust performance in face of parametric uncertainties in the alternator model. In particular, it is shown that using multiple sliding surfaces would help to reduce chattering and increase the performance speed and precision of the system. The behavior of the system in terms of convergence characteristics is analyzed using a Lyapunov-like stability analysis. Simulation results demonstrate the efficiency of the proposed controller in terms of power maximization, robustness, and convergence speed.