SoC-Based Dynamic Droop Control for Battery Energy Storage Systems in DC Microgrids Feeding CPLs

Abstract

Abstract In this paper, a dynamic state-of-charge (SoC)-based droop control and bus voltage stabilization strategy has been proposed for battery energy storage systems (BESSs) feeding constant power loads (CPLs). Firstly, a SoC-based dynamic droop control is proposed to realize proportional distribution of power. Secondly, a dynamic average consensus (DAC) algorithm is adopted to ensure that all SoC converge to the same value simultaneously. Thirdly, a nonlinear disturbance observer (NDO) and a backstepping controller are integrated to stabilize the DC bus voltage. In this way, the rapid voltage recovery and power distribution are obtained when droop coefficient is time-varying. Simulation results verify the feasibility and effectiveness of the proposed control strategy.