Performance analysis of a battery charger with BQ24650

Abstract

This paper analyzes the smart charger performance for solar photovoltaic energy applications on isolated generating systems with a synchronous buck converter topology using a BQ24650 charger controller from Texas Instruments. The solar battery charger includes different operating modes, which may be voltage or constant current, both help to increase the battery life, also uses a maximum power tracking algorithm with the voltage tracking method, thus, optimizing the energy captured by the solar panel. This analysis shows in detail a theoretical study of the main conduction and switching losses. The battery charger works up to 50 watts at rated power, its performance is greater than 94%. The main losses are the transistor conduction losses, which represent 42% of the total losses. The experimental results are compared with the theoretical analysis, obtaining similar results which support the study.