Realization of Efficient AC-DC Bidirectional Converter for a DG Application by Using SVPWM

In recent years, a system that makes use of various types of energy has been sought after and the distributed generation system that uses alternative energy such as vehicle power sources like the uninterrupted power system and hybrid electrical vehicles, fuel cells, solar cells and etc. are being studied actively. In these systems, for the greatest efficiency, the control of the charging and discharging systems to give and take energy between the DC bus and storage equipment’s and the dual voltage system require voltage step-up since the load increase in independent power source systems are essential. Therefore, bidirectional DC/DC converters are required to enable the give and take of energy between the different dc sources and to allow for control using efficient modulation scheme. Due to the limitations of energy sources of these systems, the conversion efficiency is very important. Generally, as a bi-directional coupled Buck-Boost DC/DC converter, in the isolated mode does not reverse the polarity and the current although the switch and diode is smaller than that of other converters. As such the conduction loss is small and the efficiency is high and utilization of SVPWM achieves low switching loss and more flexible to control. But the converter has the problems of current and voltage pulsation at input and output, which is like the shortage of the Buck and boost converter. A high-efficiency isolated bidirectional AC-DCconverter for a 380-V dc power distribution system to control bidirectional power flows and to improve its power conversion efficiency is proposed in this work. The dynamic analysis is evaluated by using Matlab/Simulink tool and simulation results are conferred.