Enhanced Fast Frequency Control Scheme and Wide-Area Monitoring for Low Inertia Power Systems.

Rate of change of frequency (RoCoF) increases with high share of converter-interfaced generations in modern low-inertia power systems. Consequently, system operators will have system stability challenges if they rely on classic frequency control schemes. This study demonstrates an innovative fast frequency control scheme and wide-area monitoring system developed for low-inertia grids. This can acquire precise frequency data at a zonal level, estimate the required rate and volume of fast response and then enable the initiation of this response within 0.5 seconds of a system frequency disturbance. The effectiveness of the proposed interim frequency control scheme against two methods in literature is verified based on a 36-zone Great Britain power system developed in DIgSILENT PowerFactory. Further, sensitivity analysis is used to investigate the impact of different parameters like RoCoF measurement time and communication latency. The proposed scheme allows low-inertia grids to operate with increasing volumes of non-synchronous generation.