Effective Control of Smart Hybrid Power Systems: Cooperation of Robust LFC and Virtual Inertia Control Systems

Abstract

A modern power system is expected to consist primarily of renewables, which either lack or have less rotating masses (i.e., source of inertia) compared to the traditional generation sources. However, the growth of renewables generation, based on power electronics, can substantially decrease the inertia levels of renewable power grids, which can create several frequency stability issues, resulting in power system degradation. To address this issue, this paper presents a recent virtual inertia scheme predicated on electric vehicles (EVs) to mimic the necessary inertia power in low-inertia smart hybrid power systems (SHPSs), thus regulating the system frequency and avoiding system instability. Moreover, to guarantee robust performance and more stability for SHPSs against multiple perturbations, system uncertainties, and physical constraints, this paper also proposes a robust control strategy relying on a coefficient diagram method (CDM) for the load frequency control (LFC) of SHPSs considering high renewables penetration and EVs. The efficacy of the proposed system (i.e., robust LFC with the proposed VIC strategy) is validated by comparison with a conventional LFC with/without the proposed VIC system. In addition, the simulation outcomes show that the proposed system can considerably support smart low-inertia hybrid power systems for many different contingencies.