Residual Capacity Estimation for Battery Energy Storage of Micro Grid with an Adaptive Coulomb-Counting Method

This study is to estimate residual capacity in battery energy storage systems (BESSs) based on model-based design and Coulomb-counting method. To maintain the balance of momentary energy within the micro-grid, the auxiliary reserve services have to frequently absorb and approach power flow applied technique for its high peak shaving and valley filling service. Therefore, how to approach the power quality problems of distributed energy under the safe and stable operation can play the significant role to sustain the reliability of power supply. This paper presents unique approaches to deriving adaptive Coulomb counting controller in terms of state of charge tracking control laws, on which state of charge tracking and residual power estimation can be achieved. Simulation results obtained from a 336 watt-hours BESS have verified the analysis and discussion.