A Power Allocation Strategy for Hybrid Energy Storage System Based on Dynamic Virtual Impedance Network

This is the authors' abstract. We don't add key points for this paper.

In order to achieve better power allocation results and more control objectives for the hybrid energy storage system (HESS), this paper proposes a power allocation strategy for battery-supercapacitor (SC) HESS based on dynamic virtual impedance network. After investigating the relationship between the virtual impedance network and the filter, the proposed method optimizes the virtual impedance network with multiple controlled targets, which obtain the functions of energy source power division, DC bus voltage regulation and SC State of Charge (SOC) self-recovery. In addition, the corresponding virtual impedance parameters can be dynamically adjusted according to different energy source states, realizing the reasonable power allocation of HESS while optimizing the system operation. Finally, an experimental platform is built to validate the proposed control method for the HESS composed of multiple sets of batteries and multiple groups of SCs. The experimental results have proven that power frequency division can be performed between energy sources with different characteristics, and dynamic power distribution can be implemented between branches of energy sources.