Improving performance of the P&O MPPT using derivative of photovoltaic panel voltage

This paper proposes a modified maximum power point tracking method (Perturbation and Observation) based on the use of the information from the derivative of power and the derivative of the voltage on the PV panel. The main contribution of this work resides in the employment of the derivative of voltage that is used to determine instantaneously the increment or decrement ratio of the converter duty cycle. The use of this derived signal improves the performance of the proposed MPPT method in comparison to the conventional P&O strategy, considering the dynamic system response, steady state error and robustness (against different irradiation and temperature profiles). In order to validate this MPPT proposal, a prototype of a microinverter based on the flyback converter aiming at connecting PV panels to the power grid was implemented. The microinverter control strategy was held on the Matlab/Simulink^© environment together with the dSPACE^© platform. This paper presents the simulation and experimental results along with their analysis.