Implementation of a strategy to improve the efficiency of battery chargers with double conversion topology, high power factor, and low THDi

Abstract

This paper presents a comparison between different Power Factor Correction topologies (PFC), highlighting the main advantages and disadvantages of the implementation requirements for a battery charger. Subsequently, the cascade connection of boost and buck converters is selected, for which a detailed loss analysis is performed, whose results are used to develop an operating strategy that allows the controller to act on a range of combinations of duty cycles to maximize the efficiency of the converters, maintaining adequate levels of voltage and current regulation, efficient regulation of battery recharge, high power factor, and low THDi. Finally, this converter is implemented with the mentioned operating strategy to perform constant power battery recharging, and the experimental results are presented with special emphasis on efficiency, power factor, and THDi, the latter being compared with the IEC 61000-3-2 standard.

Keywords

• Battery charger
• PFC topologies
• Buck converter
• Boost converter
• Loss analysis