LFC by coordinated virtual inertia mimicking and PEVs in power utility with MW-class distributed PV generation

This paper presents a load frequency control (LFC) by using distributed energy storage systems (ESSs) and plug-in electric vehicles (PEVs) in a large power system with MW-level distributed PV generation. The ESSs are controlled to mimic virtual inertia. Controls are done in two levels: central and local. An optimal virtual inertia is calculated considering the total PV power variation in a control area. Based on this, central ESS power command is decided and by coordination, this central ESS power command is distributed to the local ESSs to emulate the optimal virtual inertia. PEVs are used for the LFC considering user convenience, availability and state of charge (SOC) of the batteries. Effectiveness of the proposed method to provide LFC is verified by numerical simulation results.