IBR-FaultScreen is a free, open-source IBR fault screening tool for power engineers, students, and educators. It shows which grid faults become risky as solar, wind, and battery plants replace synchronous generators.
Why fault screening changes with IBRs
Synchronous generators have a spinning mass. During a fault, they help hold voltage and keep the grid in step. Inverter-based resources (IBRs) behave differently. They have no rotor, and their current is limited by their controls.
As a result, a fault the grid once rode through can now cause new problems. For example, an inverter can see voltages outside its NERC PRC-029-1 ride-through limits and trip. In other cases, voltage recovers too slowly after the fault clears.
However, studying every possible fault takes time. That is why screening matters: it shows which cases deserve a detailed study first.
How the IBR fault screening tool works
IBR-FaultScreen simulates three-phase faults with the ANDES power-system simulator. It then labels each case RISKY or OK and gives the reason. The tool checks four failure modes:
- rotor-angle instability
- slow voltage recovery
- IBR ride-through exposure under NERC PRC-029-1
- frequency outside its limits
In addition, an equal-area view shows why the synchronous machines stay in step, or lose it.
Try it in your browser
Below, you can build a grid of your own. First, choose which generators become IBRs. Next, pick the fault location and how fast it clears. We simulated all 37,120 combinations on the IEEE 39-bus test system in advance, so the results appear at once.
After that, test your judgment with the quiz. You can also run real simulations in Google Colab, with nothing to install. The full source code is on GitHub.
This IBR fault screening tool is a learning and screening aid. It uses a public test system and generic models, so it does not replace an interconnection study.
IBR-FaultScreen
Which faults become risky as solar, wind and batteries replace synchronous generators? Explore 37,120 simulated fault cases on the IEEE 39-bus system in your browser. No install needed.
Explore
Pick which generators become IBRs, the fault location and the clearing time. See RISKY or OK with the reason: rotor angle, voltage recovery, NERC PRC-029-1 ride-through or frequency.
Open the explorer →Run real simulations
Open the Google Colab notebook and run ANDES simulations yourself, including the equal-area view and the critical clearing time. Free, in the browser.
Open in Colab →Install it
Screen your own scenarios, build datasets and train the screening model on your computer.
pip install ibr-faultscreen
Try it here
Loads the full interactive demo on this page (about 4 MB).
Screening aid for education and early-stage studies; it does not replace interconnection studies. IEEE 39-bus test system, generic WECC IBR models, illustrative limits. Cite: software 10.5281/zenodo.23290219 · dataset 10.5281/zenodo.23290449 · GPL-3.0-or-later · by Shaibu Ibrahim, P.E.
Also, if you want to determine the strength of the grid when interconnecting other power plants, especially renewables like solar or wind, try the short-circuit ratio (SCR) tool here.
