Summary 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.