Engineering the future – application of advanced grid-scale inverters

The Application of Advanced Grid-scale Inverters in the NEM paper also outlines how the shift from synchronous generation towards inverter-based resources (IBR) is changing the way we must – as an industry – plan for the secure operation of the National Electricity Market (NEM).

This includes AEMO working with industry to engineer a power system capable of running at 100% instantaneous penetration of renewable energy, including grid-scale solar, wind, hydro, biomass and rooftop PV.

AEMO Manager of Future Energy Systems, Chris Davies, said the paper focusses on the potential of advanced grid-scale inverter technology to support the operation of the NEM as the penetration of IBR increases, particularly through the use of grid-forming capabilities that can help stabilise the grid.

“The NEM is undergoing a once-in-a-lifetime transition from synchronous generation, such as thermal and hydro, to variable inverter-based renewable generation,” Mr Davies said.

“When offline or decommissioned, synchronous generators can no longer provide the critical system stability capabilities that the grid relies on, requiring these capabilities be provided by different technologies.

“AEMO has been working with stakeholders to understand the potential of grid-forming inverters to address many of the challenges facing the future power system,” he said.

Deep collaboration with industry stakeholders informed the paper, helping AEMO identify four key areas of application for advanced inverters, including connecting IBR in weak grids, supporting system security, island operation, and system restart.

“To realise the potential of this technology, we need to quickly come together as an industry to prioritise the time and resources needed to prove this technology at scale and support an effective transition,” said Mr Davies.

Developed as part of AEMO’s Engineering Framework, the paper sets out clear recommendations for immediate action to capture the opportunities of advanced inverters:

• Enable connection of grid-forming projects – to enable testing and demonstration of grid-forming projects at scale, a pathway is needed to enable secure and timely connection of these projects.
• Define necessary capabilities – an absence of clear specifications makes it challenging for developers to specify their requirements to design inverter offerings. Clear definitions need to be established to assist delivery of solutions that meet power system requirements.
• Enabling capabilities on new grid-scale batteries – further funding and support is needed to assist as many new grid-scale battery deployments as possible to incorporate grid-forming capabilities, to build a fleet that can support the transition to high IBR penetration by 2025.

Further collaboration with stakeholders will be needed to develop effective pathways toward the application of advanced inverters and AEMO continues to work with industry to identify additional priority actions needed to prepare the future power system.

To get in touch with AEMO regarding the contents of this white paper, to seek more information about how to engage in upcoming engagements for the Engineering Framework, or to sign up to AEMO’s Engineering Framework mailing list, please contact AEMO at FutureEnergy@aemo.com.au.