Fast Frequency Response Constrained Unit Commitment for Low Inertia Grids

Integrating renewable energy sources (RES) into power systems is crucial for the transition towards a more sustainable and decarbonized energy system. However, the increasing penetration of RES can pose challenges to the stability of power systems, particularly frequency stability, due to the reduced total inertia. The development of advanced inverter technologies has enabled the provision of fast frequency response (FFR) services such as synthetic inertia to overcome this challenge. Recent research has investigated the provision of FFR services for low inertia power systems using a frequency-constrained unit commitment framework. The study employed an IEEE 39-bus system with varying levels of wind and solar generation penetration to examine various frequency parameters. The research focused on investigating the impact of renewable energy penetration on frequency security metrics such as the rate of change of frequency (RoCoF), the nadir frequency, and the quasi-steady state frequency. The study's findings indicate that increasing renewable power penetration, with or without synthetic inertia capability, can increase RoCoF, lower frequency nadir and less stable quasi-steady state. Therefore, it is crucial for system operators to investigate the impact of high renewable penetration and design strategies to maintain frequency stability.