A new approach to maximum power point tracking for sudden changes in irradiance in photovoltaic systems

Abstract

Background/Objective: This paper presents a new digital control approach to track the Maximum Power Point (MPPT) for Potovoltaic (PV) systems. A photovoltaic power generation system requires an effective controller to overcome sudden changes to irradiance and to maximize its efficiency. Methods/Statistical Analysis: A new approach to MPPT based on voltage control was proposed, while a PI (Proportional Integral) controller was combined with the boost converter to adapt the duty cycle. Findings: The input voltage reference was adaptively perturbed with variable steps until the maximum power was reached. A state-space model was derived through the averaging method, with the control input being the duty ratio to regulate the pulse width modulator on the DC-DC boost converter. The proposed control scheme eliminated steady state oscillations around the working point area of the PV panel when there were rapid changes to the irradiance. Applications/Improvements: Furthermore, the PV system became more efficient, as proven by the sudden change in the radiation conditions for 0.3 seconds, where approximately 30% of energy could be saved.