Maximum Power Point Tracking – A Study of Photovoltaic Systems in Supplying Stand-Alone and Grid-Connected Electrical Loads

This paper proposes two appropriate control methods for Maximum Power Point Tracking (MPPT) of a photovoltaic system in stand-alone and grid-connected conditions. Two algorithms were applied in this article: Incremental Conductance and Innovative Fuzzy Control. These algorithms were simulated and compared; therefore, on the basis of the best algorithm, the influence of environmental factors such as temperature and radiation intensity on the photovoltaic array and the controllers' response were studied. The control strategy in grid-connected condition was based on Instantaneous Reactive Power theory and inverter switching was implemented using the Adaptive Hysteresis method. The MATLAB simulation results illustrated the acceptable performance of the proposed system in achieving MPPT for two conditions of stand-alone and grid-connected loads due to the variable temperature and radiation. Furthermore, results indicated the compensation of current harmonics and reactive power of nonlinear loads.