Design, sizing and set up of a specific low cost electronic load for PV modules characterization

In this paper, the design, sizing and set-up of a specific low cost electronic load, based on a DC-DC step-down converter, suitable for the PV module I - V characteristic curves determination, is described. In particular, for its set up, a low cost and user friendly micro-controller has been employed in order to generate the PWM signal. The measures carried out connecting the electronic load prototype to a commercial PV module are here presented and discussed. The conceived electronic load has allowed the determination of 80% of the PV module characteristic curves in 2 s. This low measurement time, lower than the time intervals in which weather conditions may change, allows to assume as constant the PV module temperature and the environment conditions. The obtained characteristics, affected by a limited ripple, have been compared with simulation data from the Matlab/Simulink implementation of the most common PV module four and five lumped parameters with good results.