Control and Hardware-in-the-Loop Simulation of Community Energy Storage Systems Based on Repurposed Electric Vehicle Batteries

The increasing availability of used Electric Vehicle Batteries (EVBs), as well as the environmental concerns associated with their disposal, have led to increased interest in reusing them in grid-scale stationary energy storage systems. This paper proposes the utilization and control of repurposed EVBs in Community Energy Storage Systems (CESSs) in Low-Voltage (LV) distribution networks. A real-time Community Energy Management System (CEMS) is proposed for the control of the CESS, which uses repurposed EVBs and a power electronic interface comprised of a four-quadrant ac/dc converter and a bidirectional dc/dc converter together with the corresponding controllers. To assess the capability of the controller in providing CESS services in the form of active and reactive power control in an LV residential distribution network, four case studies are carried out using Hardware-in-the-Loop (HIL) simulations. The HIL simulations use an actual battery pack and a four-quadrants converter system. The impact of the proposed controller on the repurposed EVBs’ cycling performance is evaluated using a Rainflow Counting Algorithm (RCA). The distribution transformer Loss of Life (LoL) is also estimated. The HIL simulation results demonstrate the effectiveness of the proposed real-time CEMS in slowing down the degradation of the battery and LoL of the distribution transformer, while improving the LV distribution system’s voltage profile.