Multiport Resonant DC-DC Converter using Actively-Controlled Inductors for Hybrid Energy Storage System Integration

In the field of heavy-duty electric vehicles and charging infrastructure, the energy sources are susceptible to transients with different amplitudes and dynamics. Energy storage systems (ESSs) must be designed by a trade-off between specific response time and energy density, because one single energy source is insufficient to supply such a high power system. Integrating ESSs with different capabilities, such as fuel-cell, battery, and supercapacitors, as a single energy source is required. In this context, a resonant multiwinding transformer-based (MTB) converter can be used to efficiently interconnect these different ESSs to the load, since the resonant converters are able to operate at a high switching frequency and hence enable high bandwidth control. However, due to the multiple resonant circuits and possible parameter deviations, the control capability might be compromised. Thus, a multiport resonant dc-dc converter embedded with variable inductors is proposed to enhance the power flow management among these different ESSs with reduced conversion stages. Further, the proposed concept can also improve the immunity to parameter deviations on the resonant by compensating the resonant frequency. Finally, simulations and experimental results of a 4-port resonant dc-dc converter embedded with variable inductors are presented to demonstrate the effectiveness of the proposed system.