Thermal imaging based maximum power point tracking for solar modules in variable ambient temperature

Abstract

AbstractIn this study, a thermography based modified perturb & observe maximum power point tracking (P&O MPPT) technique is proposed and implemented to overcome challenges due to unstable environmental temperature and radiance. A temperature based empirical model of PV module is used to approximate the peak power parameters. The objective of using temperature based model is to minimize the difference voltage (∆V) signal which in turn decreases the time to reach maximum power point and hence increases the speed of the MPPT system. Less number of iterations to achieve maximum power point also improves the output signal quality by reducing the number of fluctuations in the signal. Although the temperature based MPPT methods have already been suggested in literature but the novelty of the proposed method lies in using infrared (IR) images to monitor the instant temperature of photovoltaic (PV) module, which give its advantage in the form of fast and stable steady-state output. Results of the proposed scheme are found better when compared to the conventional P&O MPPT.