Large-Scale Battery Energy Storage System Dynamic Model for Power System Stability Analysis

The increasing penetration of renewable energy sources in the grid can raise the likelihood of instability in the power grid, e.g. small signal and voltage instability incidents. To study the effect of BESS integration on the grid and power system behavior, accurate battery modeling plays a key role. As the majority of power system studies including small signal stability analysis is carried out in the
$d-q$
axes, a precise model of the battery in the
$d-q$
axes is necessary. The lack of parametric based models of the battery in
$d-q$
axes makes stability analysis more challenging especially as the contributions of batteries in power systems are growing rapidly. In this paper, we develop an analytical model for the battery and its inverter in
$d-q$
axes. To validate the fidelity of the model, we simulate both the original and the obtained
$d-q$
models and compare the simulation results.