Nine switch bidirectional converter for hybrid AC/DC microgrid system

In this paper a nine switch bidirectional power converter is proposed for Hybrid AC/DC microgrid system with battery energy storage. By using distributed generation (DG) and energy storage system, it overcomes the existing power system capacity limitations and simultaneously handles local AC/DC load along with grid. The proposed bidirectional power converter reduces the switch count and controls power flow with higher reliability. To control the bidirectional power flow, carrier based sinusoidal pulse width modulation (SPWM) is used with only one PI controller. A novel buck-boost circuit for battery charging and discharging is developed. The proposed converter is integrated with impedance source network to obtain their unique advantages such as shoot through stability, buck-boost operation from DC link and reduced inrush current during starting. The viability of this proposed converter is validated through Matlab simulation and results are provided.