Modified incremental conductance MPPT algorithm to mitigate inaccurate responses under fast-changing solar irradiation level

During the increment of solar irradiation, the conventional incremental conductance algorithm responds inaccurately at the first step change in the converter duty cycle. This paper presents the conventional algorithm confusion and proposes a modified incremental conductance algorithm that responds accurately when the solar irradiation level increases. Moreover, the proposed algorithm shows zero oscillation in the power of the solar module after the maximum power point (MPP) is tracked. MATLAB simulation is carried out with the modified incremental conductance algorithm under a fast-changing solar irradiation level. Results of the modified, conventional and variable step size incremental conductance algorithms are compared. Finally, the hardware implementation, consisting of a single-ended primary-inductor converter (SEPIC) and a PIC controller, is applied as the maximum power point tracking (MPPT) controller. The simulation and experimental works showed that the proposed algorithm performs accurately and faster during the increment of solar irradiation level. (C) 2014 Elsevier Ltd. All rights reserved.