Design, Control and Prototyping of a Bidirectional Dual Active Bridge Converter for integrating a Sodium Metal Halide Battery into a Telecom Station

The paper presents the design, control and prototyping of a Dual Active Bridge converter (DAB) devoted to interface a Sodium Metal Halide Battery (SMHB) to the DC grid of a telecom station. The design process is accomplished starting from telecom DC supply and SMHB specifications, especially power and voltage ratings and their corresponding variation ranges. Furthermore, DAB components are selected carefully based on an extensive performance analysis to maximise the energy efficiency, by enabling Zero-Voltage Switching (ZVS) over wide power and voltage operating ranges. The effectiveness of the proposed configuration is guaranteed also by a nested PI-based control system, which avoids unsuitable DC-bias current components by a proper management of phase-shift variations. Both simulations and experiments are presented and discussed, which corroborate the validity of all the design solutions.