A Novel Multi-Port High-Gain Bidirectional DC-DC Converter for Hybrid Energy Storage Applications

This work presents a novel multi-port high-gain bidirectional DC-DC converter (MPHG-BDC) designed for energy storage systems with consumer benefits. The proposed MPHG-BDC enables the integration of multiple low voltage sources, utilizing modular converters to achieve high step-up gain in boost mode and high step-down gain in buck mode through the voltage multiplier. Thus, facilitating the grid to vehicle (G2V) and vehicle to grid (V2G) power flow, which the consumers can utilize the electric vehicular batteries as a backup power supply. Thus, facilitates power availability even in remote areas for household electrification. The highlights include reduced averaged normalized switch voltage stress, continuous LV currents, multiple low-voltage source integration, and ease of control. The proposed MPHG-BDC is thoroughly analyzed under steady-state conditions, with and without accounting for the non-idealities. A detailed examination of the boost and the buck modes, loss analysis, and comparison with existing bidirectional converter topologies are provided to showcase the performance of the proposed converter. The overall efficiency of converter is analyzed and discussed. At rated conditions, the efficiency in the boost mode is 93.2% and in buck mode is 92.7%. The operation with independent source operation (failure mode case) is verified and results are presented. The theoretical aspects are validated using a 100W laboratory module.