Bidirectional Interleaved Two-Stage Converter for DC Microgrids

This paper proposes a two-stage bidirectional interleaved buck converter designed for efficient energy exchange between DC-microgrid and batteries. The first stage utilizes an isolated full-bridge CLLC converter with open-loop fixed-frequency control, ensuring zero-voltage switching. The second stage employs an interleaved buck converter with PWM control for precise voltage regulation, reducing switch voltage stress and output current ripple. A PSIM software is used to simulate the circuit operation. A simulation prototype of two-stage bidirectional interleaved buck converter demonstrates output power of 1 kW, input voltage of 400 V, and output voltage ranging of 40∼58 V. The proposed design holds great promise for enhancing efficiency and reliability for a DC-microgrid and energy storage systems.