Provision of Virtual Inertia Support Using Battery Energy Storage System
Keywords:frequency control, power system inertia, renewable energy sources, battery energy storage systems
The paper presents the importance of the grid inertia constant for the frequency stability of the future high-res low-inertia power systems. Since more and more renewable energy sources (RES) are being connected to the power system via frequency converters, the grid inertia constant is reduced. This issue can be mitigated by applying appropriate control mechanisms through which RES can provide virtual inertia and provide rotating reserves for primary frequency control. The concept of a virtual synchronous generator for providing virtual inertia is elaborated, as a solution to the presented problems. By applying virtual synchronous generators, RES can provide support for frequency control during disturbances almost like conventional synchronous generators. The influence of virtual inertia on the stability of the Croatian power system was analyzed using a battery energy storage systems (BESS) with a control mechanism that enables its participation in frequency control.