Energy Management Strategy for DC Microgrid of Multi-Energy Storage Based on Adaptive Droop Control

As a typical method to implement the equilibrium between microgrid coordinated control and the State Of Charge (abbr. SOC) of Energy Storage Units (abbr. ESU), and the droop control is affected by its own SOC, capacity and ultimate capacity as well as bus voltage quality and mismatching line impedance. Synthesizing above-mentioned factors, an adaptive droop control based energy management strategy for DC microgrid was proposed. In this control strategy, the power was distributed among ESUs according to its own SOC and capacity to effectively avoid the over-charging and over-discharging of ESU, meanwhile the voltage compensation link and power compensation link were introduced in to respectively eliminate the voltage deviation caused by droop control and the power deviation caused by line impedance. The power correction link was set up to avoid the appearance the out-of-limit of power distribution among ESUs. Simulation results verify the effectiveness of the proposed energy management strategy.