Improving Frequency Regulation for Future Low Inertia Power Grids with Increased Penetration of Variable Generation: A Review

Abstract

The modern Power system is witnessing an unprecedented increase in the penetration of renewable Variable Generation sources. Increased penetration of Converter interfaced Variable Generation like solar PV and Wind power while replacing conventional Synchronous Generators introduces new challenges to grid operators in terms of dynamically handling frequency stability and regulation. Reducing the number of Synchronous generators while increasing non-synchronous, inertia-less Converter Interfaced Variable Generation reduces grid natural inertia, which is critical for maintaining frequency stability. Frequency regulation for low inertia power grids has become pertinent topic for research. This paper reviews recent solutions proposed in literature to address the low inertia problem to improve frequency stability. Additionally, it highlights the formulation of an optimization problem for Virtual Inertia sizing and placement as well as techniques applied in solving the optimization problem. Finally, gaps in literature that require further research were identified.