Simulation of a High Power Self-Equalized Battery Charger Using Voltage Multiplier and Phase-Shifted Full Bridge Converter for Lithium-Ion Batteries

Lithium-Ion batteries and super capacitors traditional energy storage systems(ESSs) need a voltages balancing circuit to remove voltage imbalance and one bidirectional dc-dc converter to control the charge process. Since these two separated circuits need several sensors, switches, inductors and multi windings transformer, the complexity and volume of ESS is boosted. In this paper, a self-equalized charger for lithium-ion batteries is proposed which consists of a phase-shifted full bridge dc-dc converter for charging operation and a voltage multiplier for eliminating voltages imbalance. Owing to integrated structure of the proposed circuit, complexity and volume of the system are reduced. By using phase-shifted method, the converter experiences ZVS operation which gives rise to high efficiency and control simplicity.