Using Self-Synchronization Error Dynamics Formulation Based Controller for Maximum Photovoltaic Power Tracking in Micro-Grid Systems

This paper proposes a self-synchronization error dynamics formulation based controller for maximum photovoltaic power tracking (MPPT) of a photovoltaic (PV) array. The output power conversion of a PV array depends on atmospheric conditions, such as the solar radiation and ambient temperature, and its conversion efficiency is low. Therefore, a MPPT controller is necessary for a PV conversion system, in order to improve the output power. A PV cell is a p-n semiconductor junction. Photon motion, temperature, or electricity conduction cause anomalous diffusion phenomena in inhomogeneous media. In order to describe nonlinear-characteristics, fractional-order calculus can be used to express the dynamic behaviors using fractional-order incremental conductance and to adjust the terminal voltage to the maximum power point. Inspired by the synchronization of Sprott system, a voltage detector is formulated to trace the desired voltage and to control the duty cycle of a boost converter. For a small photovoltaic system, the numerical experiments demonstrate that the proposed method can reduce the tracking time and can improve the conversion efficiency.