PHOTOVOLTAIC SYSTEM MAXIMUM POWER POINT TRACKING

Photovoltaic system maximum power point tracking methods and apparatus are disclosed. Output power samples from one or more photovoltaic (PV) cells are obtained. The output power samples include perturbed samples for which a perturbation is applied to an operating voltage or current of the PV cell(s) and non-perturbed samples for which no perturbation is applied to the operating voltage or current. A control output, to change the operating voltage or current of the PV cell(s) for a next perturbed sample by a next perturbation, is generated. The next perturbation could be based on an estimated change in output power due to a previous perturbation. The next perturbation could also or instead be in a direction based on a change in output power samples, and of a magnitude based on the direction and a direction of perturbations applied for one or more perturbed samples preceding the next perturbed sample.