SoC-based Decentralized Power Management in Multi BESS-PV for EVs Charging Applications

The grid-interactive charging station powered by PV and multiple energy storage systems is proposed to have a decentralized power management scheme (DPMS) in this article. The key feature of the proposed DPMS is to reduce the system complexity while enabling easy extension of load as well as new renewable sources. The DPMS considers all possible variations of PV, grid intentional/unintentional non-availability, and changes in local loads. It has the feasibility to detect the mode of operating of the system without measuring load currents and powers or any kind of communication. Grid end bidirectional converter transfers real power between DC bus and utility grid in effect with line compensated droop with the storage system. Additionally, it provides ancillary services including harmonic reduction, reactive power assistance for utilities, and maintenance of unity power factor (UPF) at the point of common connection (PCC). In the proposed system, power-sharing is utilized based on the SoC of the battery to enhance the lifecycle and also reduce the current stress on the battery. It provides smooth dc-bus voltage regulation. During the autonomous mode of the grid, the various condition is addressed such as PV output variation, load changes, etc. MATLAB simulation is performance d to verify the proposed DPMS.