Optimal Control Strategy of Battery Energy Storage Systems to Support Grid Forming Capability

Jeju island power system in Korea will be operated with high penetration of inverter-based resources (IBRs). Grid forming inverters (GFMs) are considered to provide several advantages that enable the utilization of renewable energy (RE) generators to be maximized. A virtual synchronous generator (VSG) type GFM increases the benefits because it can imitate the inertial response of conventional generators so that the frequency stability of power systems with low inertia can be maintained. To improve the performance of VSG type GFM to support power balance in the system, a battery energy storage system (BESS) can be provisioned which is capable of compensating RES output as a power source for the GFM. A model predictive control (MPC) is used as a BESS controller so that optimal BESS power can be used to support the RE connected to the system via GFM by considering BESS and system constraints.