UNSW launches grid protection project for grid-forming BESS and inverters

Researchers at Australia’s University of New South Wales (UNSW) have launched a new project to address challenges associated with the secure operation of power systems with high shares of inverter-based resources.

Unlike conventional coal-fired generators, inverter-based resources can provide different fault currents, potentially making faults harder for existing protection systems to detect. The team will investigate these challenges to help future-proof Australia’s renewable energy transition.

“Essentially, we need to keep operating a safe and reliable power system,” UNSW Sydney Associate Professor in Energy Systems Georgios Konstantinou said in a statement. “This work will help to future-proof, manage risks and reduce the costs associated with renewable power systems. It will be a continuous process of informing both industry and the research community about problems and solutions with inverter-based resources (solar, wind, batteries), their fault current contributions and power system protection.”

The project, titled Protection & Relay Operation for Inverter-based Low-inertia Electricity Systems (PROFILES), will run for three and a half years until the end of 2030, at a total cost of AUD 12.9 million. About half of the funding was awarded in a grant from the Australian Renewable Energy Agency (ARENA). Other industry partners include Transgrid, the Australian Energy Market Operator (AEMO), ElectraNet, Power Electronics, SMA, Tesla and Siemens.

AEMO had previously highlighted the need to ensure that grid-forming inverters can provide fault currents that allow protection systems to operate reliably. The PROFILES project was established in response to that, aiming to establish a basis for how grid-forming battery energy storage systems can support system security and interact with protection systems when providing fault current.

“It will assess protection equipment options and identify where replacement or reconfiguration may be needed so transmission network service providers can factor these requirements into maintenance and future design strategies,” the project page states. “The work is also intended to support least-cost system strength procurement decisions and establish the technical foundations for future higher-fidelity studies, including potential network trials.”

Specifically, the project will use modeling, simulation and hardware-in-the-loop testing to better understand the relationship between inverter-based resources and the operation of grid protection systems.

Hardware-in-the-loop testing, which connects physical equipment to a real-time simulation, will be carried out at UNSW Sydney’s Real-time Digital Simulation (RTS) Laboratory. The facility is the largest of its type in Australia. It includes an 18-rack real-time digital simulator, protection relays and amplifiers for relay testing, as well as equipment for controller and power hardware-in-the-loop testing.