This report summarises the operations of the Hornsdale battery during the first half of 2023, marking one year since the implementation of grid-forming capabilities.
Report extract
In discussions with AEMO, an important consideration has arisen when quantifying the inertia contribution from inverter-based technology, and the amount of headroom that is available.
In the case of traditional synchronous generators, the amount of inertia available is inherently linked to the mass and velocity of the rotating elements, whereas in an inverter the amount of inertia available is limited to the maximum output limit and the active power setpoint at that point in time.
As the active power setpoint increases, the inertia contribution from an inverter starts to reduce due to lower available headroom before the plant hits its maximum operating limit.
The magnitude of the response, and the headroom needed, is dependent on the inertia settings and the extent of the frequency deviation.