New flexible bidirectional converter for electric vehicle substations connecting microgrids

Abstract This paper proposes a flexible and energy-efficient power conversion system capable of bidirectional energy flow betweenAC and DC microgrids, as well as electric vehicles (EVs). The converter is designed by integrating fundamental DC/DCtopologies—namely Push-Pull and Half-Bridge converters—with a multi-level DC/AC inverter. It supports multiple operatingmodes, enabling seamless integration of both fixed and mobile EV charging stations through dedicated DC/DC charginginterfaces tailored to various system configurations. A hierarchical multi-agent control strategy is employed, with clearly definedroles for each converter control component, enabling coordinated operation across diverse use cases. Simulation resultsconducted in MATLAB demonstrate a high power factor of up to 96.5% during both EV charging and discharging processes tothe interconnected microgrids. The system accommodates EV input voltages ranging from 350 to 1500 VDC and currents from15 to 45 A, covering a wide range of medium to fast charging levels. The optimal switching frequency is determined through adetailed power loss analysis across input and output stages. The proposed converter offers a compact design, supports a widerange of voltage levels with low battery-side ripple, and ensures efficient bidirectional energy conversion between various grids.