Parallel resonant converter for battery charging application

Battery energy storage system has become an important part of modern energy system with the growth of renewable energy and electric vehicle (EV). With the development of recent battery technologies, the improvement in overall battery charging efficiency and its cost, have become critical issues because, as the charger efficiency increases, the charging time and electricity cost decreases. Furthermore, power electronics based chargers can cause line current distortions and harmonic issues in the ac power system; and hence efficient and low-distortion smart chargers are needed to minimize power system disturbances. The aim of this paper is to study and analyze the conventional charging algorithms and the power converter topologies available in practice to design a fast, effective and efficient battery charger for EV/Microgrid/Energy storage applications. An LC Parallel Resonant Converter (PRC) can offer an effective solution for designing a fast and reliable battery charger with simple control circuits and techniques. The distinct feature of the proposed topology is that, the converter can operate in open loop while maintaining a constant charging current and hence any of the fast charging algorithms can be easily implemented without any complex controller and sensors