Photovoltaic (PV) systems are commonly controlled using PI or PID structures, which cannot ensure global stability and a constant settling time. Therefore, the optimization algorithms, e.g. Perturb and Observe (P&O), are designed using the highest settling time in the operating range, which produces a slow tracking of the maximum power point (MPP) for the largest part of the operation range, introducing dynamic power losses to the system. This paper proposes to combine an adaptive controller and a sliding mode current controller (SMCC) to guarantee global stability and a constant settling time for any operation condition, which enable to increase the generated power in comparison with PI and PID controllers. The SMCC enables to mitigate the system perturbations and guarantee global stability, while the adaptive controller defines the reference of the SMCC to ensure a constant settling time. The design of the new control structure is supported by mathematical analyses and simulations made in Matlab®, where the robustness of the system is validated.