The increasing penetration of renewable generators can be a significant challenge due to\nthe fluctuation of their power generation. Energy storage (ES) units are one solution to improve\npower supply quality and guarantee system stability. In this paper, a hybrid microgrid is built\nbased on photovoltaic (PV) generator and ES; and coordinated control is proposed and developed to\nachieve power management in a decentralized manner. This control scheme contains three different\ndroop strategies according to characteristics of PV and ES. First, the modified droop control is\nproposed for PV, which can take full utilization of renewable energy and avoid regulating output\nactive power frequently. Second, to maintain the direct current (DC) bus voltage stability, a novel\ndroop control incorporating a constant power band is presented for DC-side ES. Third, a cascade\ndroop control is designed for alternating current (AC)-side ES. Thus, the ES lifetime is prolonged.\nMoreover, interlinking converters (ICs) provide a bridge between AC/DC buses in a hybrid microgrid.\nThe power control of IC is enabled when the AC- or DC-side suffer from active power demand\nshortage. In particular, if the AC microgrid does not satisfy the reactive power demand, IC then acts\nas a static synchronous compensator (STATCOM). The effectiveness of the proposed strategies is\nverified by simulations.
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