A novel theta MPPT approach based on adjustable step size for photovoltaic system applications under various atmospheric conditions

This study suggests and discusses a new maximum power point tracking (MPPT) approach based on an adjustable step size for photovoltaic system applications to extract the real MPP under various atmospheric conditions. The suggested adjustable step size Theta approach (ASSTA) is essentially based on the Theta angle (theta), which is the arctangent of the change in photovoltaic power derived by the variation in the photovoltaic voltage (arctan(dP(pv)/dV(pv))) and its derivation in relation to the change in the photovoltaic voltage (d theta/dV(pv)) with the use of a new adaptable step size (dP(pv) + dV(pv) x dI(pv)). MATLAB/Simulink (R) software is selected for the implementation of the overall photovoltaic system, and the simulation results in different scenarios indicate that the novel ASSTA guarantees a fast convergence speed to the real MPP under a rapid change in operating conditions (insolation and temperature) with a time fewer than 0.017 s. Furthermore, the ASSTA shows better accuracy in tracking the MPP in the case of sudden insolation and temperature change and tracks the real MPP with neglected fluctuation in steady-state operation. Its average tracking efficiency in all simulation scenarios can be between 99.10 and 99.81%. Additionally, in light of the comparative simulation results of the new ASSTA with other methods such as INC, P&O, variable step size INC (VSSINC), and PSO MPPT techniques under various climatic scenarios, it can be concluded that the novel ASSTA outperforms the other MPPT approaches and significantly boosts the tracking performance and reduces power loss.