The Partial Linearization of Power-Voltage Curve for Grid-Connected Photovoltaic System

This paper aims to present a new method to track the maximum power point for single-stage single-phase grid connected PV inverter, which is based on the partial linearization of the power-voltage PV panel curve coupled to the MPPT algorithm. The proposed approach generates the reference current in order to regulate the power fed into the grid, and it needn’tany accuracy of the PV panel model which may change over time. The current controller approach is based on the stability of the internal dynamic due to the nonlinearity of the PV system and it uses the Lyapunov function that gives globally asymptotically stable trajectories of the closed-loop system. The effectiveness of the control algorithm has been verified by simulating it in Matlab/Simulink software. The proposed control is compared with the conventional approach using PI controller.