The intermittency and unexpectedness of renewable energy and more interconnections within grids pose substantial threats such as power imbalance,voltage sag,frequency oscillations.Since Superconducting Magnetic Energy Storage (SMES) systems have a fast response speed (milliseconds),high cyclic efficiency (>95%) and unlimited times of charging cycles,they offer a key solution to stabilising power systems - damping out low frequency power oscillations and supporting voltage sags,especially for renewable power grids where generation is unexpectedly varying.