Computed current control method for maximum power point tracking of a grid-connected photovoltaic system

This paper proposes a new Maximum Power Point Tracker (MPPT) topology for a single phase, grid-connected PV system considering the sudden changes in environmental conditions. The MPPT takes into account the nonlinearity of photovoltaic (PV) array, the oscillation of PV voltage around the MPP, and the inverter filter design. The MPPT is designed so that current reference is computed directly from the PV voltage and PV current to assure the system's stability with simple control algorithm. Convergence to the MPP is obtained very fast without need of perturbation or predefined constant. Its performance in term of tracking speed is compared with the conventional Ripple Correlation Control (RCC) method under step changes in irradiation.