A novel autoscaling variable perturbation size maximum power point tracker applied to photovoltaic (PV) system

摘要

Conventional variable perturbation-size maximum power point (MPP) tracking methods use a constant multiplying factor to enable fast convergence process. However, it potentially leads to the sluggish dynamic response. In this context, a novel autoscaling variable perturbation-size MPP tracking algorithm is proposed to precisely recognize the MPP under an abrupt change in solar irradiance. Initially, a new perturbation size scaling function of the duty cycle is defined, which typically modulates the DC-DC boost converter output. The principle objective of employing this algorithm is to enable the fast dynamic response while harvesting steady-state power with nearly zero sustained power oscillations around the MPP. In a second step, a method is proposed to improve the decision-making system during a sudden change in irradiance. The proposed MPP technique optimally achieves 99.72% tracking efficiency without much computational intensiveness, which is better compared with previous MPP tracking methods. The adaptability of the proposed technique is validated through a comprehensive set of MATLAB/Simulink software simulation studies followed by a low-cost STM32F407VGT6-based microcontroller-based experimental setup. Furthermore, the reliability of the proposed algorithm is also investigated. The result implies that the proposed MPP tracker operates satisfactorily under sudden changes in irradiance.