---
id: "2024-02-21-ai-avoids-tokamak-tearing-instabilities"
url: "https://postcutoff.com/e/2024-02-21-ai-avoids-tokamak-tearing-instabilities/"
as_of: "2026-11-13T13:49:00+01:00"
date: "2024-02-21"
date_precision: day
category: science
importance: 3
confidence: high
status: [Result confirmed]
verification: Peer-reviewed
sources: 2
editor: human editor
human_review: null
version: "2026-10-04"
---

As of: 2026-11-13 13:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/e/2024-02-21-ai-avoids-tokamak-tearing-instabilities/

# AI controller predicts and avoids tearing instabilities in the DIII-D fusion reactor

Princeton and PPPL researchers (Nature, Feb 2024) trained an RL controller on past DIII-D data. It forecast tearing-mode instabilities up to 300 ms ahead and adjusted operating parameters in real time to avoid them during experiments while keeping high performance.

## Key facts
- Nature 626 (22 Feb 2024)
- Forecasts tearing instabilities up to 300 ms in advance
- Demonstrated in live DIII-D shots

## What happened

The controller learned the precursors of tearing modes from archived experiments and steered the plasma away from them.

## Why it matters

Instabilities that can damage reactors are a key obstacle to fusion power. Predictive AI control is a candidate solution for ITER-class devices.

## Your AI and this story

- GPT-6 Astra (training cutoff April 2026): in its training data
- Claude Opus 5.5 (training cutoff June 2026): in its training data
- Gemini 4 Hydrogen (training cutoff March 2026): in its training data
- Grok 4.7 (training cutoff May 2026): in its training data

## Sources

1. [Avoiding fusion plasma tearing instability with deep reinforcement learning (Nature)](https://www.nature.com/articles/s41586-024-07024-9) (nature.com, paper)
2. [Princeton Engineering: Engineers use AI to wrangle fusion power](https://engineering.princeton.edu/news/2024/02/21/engineers-use-ai-wrangle-fusion-power-grid) (engineering.princeton.edu, press)

## Changes

- 2026-09-29 (filed): Created

## Related

- 2022-02-16: [Deep reinforcement learning controls fusion plasma in the TCV tokamak](https://postcutoff.com/e/2022-02-16-deepmind-tokamak-plasma-control/index.md)