System-level co-ordination of fast frequency response capabilities from a portfolio of technology providers

Decreasing system inertia due to higher shares of renewable energy sources makes power systems more vulnerable to stability issues during sudden large disturbances. Traditionally, frequency response, and related services, were primarily provided by thermal generators; however, renewable generation, or alternative sources, will gradually be encouraged and incentivised to provide such capabilities. Various sources such as wind turbine generators, PV plants, battery energy storage systems, etc., providing a fast frequency response service, present diverse capabilities in terms of speed, shape, and duration of response. Hence, it is essential to determine how to efficiently co-ordinate the available resources to ensure system stability while avoiding over-procurement. To better understand the interactions between technology options, particularly when implemented at scale, and to propose generalised operational rules, a single bus model of the future Irish power system is employed to evaluate the frequency stability of the system for a wide range of high renewable scenarios. The advantages and disadvantages of different resource types are assessed individually, and within a suite of options, and the effectiveness of different co-ordination approaches is evaluated.