Maximum Power Point Tracking Algorithm For Non-Linear DC Sources

A boost converter based maximum power point tracking for the non-linear photovoltaic sources is proposed in this paper. As the v-i characteristic of the photovoltaic (PV) source exhibiting non-linear variation with solar insolation continuous tracking of maximum power is mandatory in order to have high overall conversion efficiency. As the tracking time depends on the type of methodology employed, optimized perturbation quantity must be used, otherwise power tracking takes long time resulting in sub-optimal operation of the PV system. In this paper a variable incremental duty ratio algorithm is proposed to reduce the tracking time and to improve the tracking performance. In this algorithm the duty ratio is high at beginning of the disturbance and it follows a geometric progression in the subsequent iterations. Proposed concept is verified experimentally and also compared with the conventional perturb and observation method.