Investigation into the Appropriate Sizing of Battery Energy Storage System for Frequency Control in a Renewable Integrated Power Grid

The growing incorporation of wind energy into power grids introduces concerns about frequency stability which leads to low-inertia grids susceptible to disturbances. Relying on fossil fuel-based units is a challenge for ensuring frequency stability during major power disturbance in grid. An alternative solution is found in Battery Energy Storage Systems (BESS), offering active power support at a very rapid response rate to maintain frequency response in the grid. However, sizing of BESS is a crucial concern to ensure performance adequacy and also to minimize economic concerns. All the simulations on a modified IEEE 39 bus test system are conducted for various wind penetration levels. Lastly, this paper introduces a novel method, utilizing polynomial regression analysis, to accurately estimate the BESS size including parameters, namely frequency nadir and Rate of Change of Frequency (ROCOF) after power disturbance. Additionally, a comprehensive performance comparison between BESS and synchronous condenser in a wind-integrated grid is presented which gives a high level of accuracy of the proposed model. Therefore, this research will assist stakeholders in future BESS installations within largescale wind-integrated grids to achieve enhanced frequency stability.