The Use of Synchronverters for Fast Frequency Response and Automatic Voltage Regulation in Low Inertia Islanded Power Networks

This paper concerns power system stability challenges for large scale integration of renewable energy sources. Specifically, the focus of this study is based on the Suðuroy power grid on the Faroe Islands, where a 7MW wind farm – equal to the maximum load for the entire grid – is scheduled for grid integration in 2021. The paper examines whether a synchronverter can help provide grid stability when the grid is solely powered by the wind farm by adding virtual inertia to the network. The operation of the synchronverter has been tested in a simulation scenario with a load step using DIgSILENT PowerFactory. The results were compared to a solution with a synchronous condenser (SC) and a battery energy storage system (BESS) with grid following operation, as opposed to the synchronverter that operates as a grid-forming converter. The simulations proved that the synchronverter has the ability to contribute to the grid stability without the typical limitations traditional solutions have. However, the results still require further investigation – both from a practical and an economical consideration – before ultimately determining if it is currently a viable alternative to already existing and typically applied solutions.