An Optimized Steepest Gradient Based Maximum Power Point Tracking for PV Control Systems
Résumé
In order to improve the photovoltaic (PV) production, the researchers are interested
in developing new methods to reach the Maximum Power Point (MPP) produced by the
photovoltaic field to be injected into the utility grid. This article describes a new method called
the Optimized Steepest Gradient Method (OSGM), it is based on the first (gradient) and second
order (hessian) derivatives of the power function in order to find the best variation of the
voltage (Vpv) with the calculation of the optimal step allowing the convergence to the tension
value (Vref) which ensures the MPP. The mathematical model has been developed and
implemented under Matlab/Simulink environment. To analyze Maximum Power Point
Tracking (MPPT) algorithm performances, time response, oscillation, overshoot and stability
are taken into account. The OSGM is implemented and compared to three others algorithms
(one of these algorithm is the ANFIS proposed in previous work). Performances obtained by
the proposed algorithm offer faster response, less oscillations around MPP and a low energy
loss. In addition, numerical computation of the gradient and the hessian of the power function
allow bypassing modeling inaccuracies.