Coordinated Active Power Control of Hybrid Energy Storage System for AC Micro-Grids in Islanding Mode

摘要

The coordinated control strategy of a hybrid energy storage system(HESS)operated in an islanded AC Micro-Grid(MG)is researched,based on which an improved active power allocation strategy is proposed.The ultracapacitor(UC)in the HESS is under droop control to regulated the system frequency and voltage directly.The lead-acid battery in the HESS is controlled based on the droop characteristic of the system frequency,and is responsible for maintaining the SOC of the UC under control and compensating the non-instantaneous power fluctuations in the AC MG.Simulation results have certificated that the presented control strategy is effective.