China Completes Testing of World’s Largest Fusion Magnet

China completed expert acceptance and full-parameter testing of two domestically developed superconducting magnets on 27 June 2026 at the Institute of Plasma Physics, Chinese Academy of Sciences, in Hefei, Anhui Province. The tested systems were a toroidal field superconducting magnet and a high-temperature superconducting central solenoid coil for fusion research.

Fusion Magnet Systems

The toroidal field superconducting magnet is a D-shaped structure that measures 21 metres in length, 12 metres in width, and 582 tonnes in weight. It is described as the largest fusion reactor superconducting magnet built so far. The toroidal field magnet is used to confine plasma inside a vacuum chamber with a strong magnetic field. In fusion devices, plasma is heated to about 100 million degrees Celsius and must remain stable for controlled operation.

Central Solenoid Coil and Fusion Control

The high-temperature superconducting central solenoid coil was also tested during the same exercise. In a fusion reactor, the central solenoid coil induces and drives plasma current, which is a core function in ignition and stable operation. Both magnet systems reached internationally leading performance levels during testing. The central solenoid coil is part of the magnetic system used in tokamak-type fusion devices.

Domestic Manufacturing and CRAFT Project

Both magnet systems achieved 100% domestic production across the supply chain, including core raw materials and fabrication processes. The project is linked to the Comprehensive Research Facility for Fusion Technology, or CRAFT, which is part of China’s “artificial sun” programme. The toroidal field magnet has 1.3 times the volume and three times the stored energy of comparable magnets used in the International Thermonuclear Experimental Reactor, or ITER. China has set a target of fusion power generation around 2030.

Important Facts for Exams

• Fusion is the process of combining light atomic nuclei to release energy, and it powers the Sun and other stars.
• Tokamak is a magnetic confinement device used in fusion research, and it uses toroidal geometry.
• Superconducting magnets can carry electric current with very low resistance when cooled to extremely low temperatures.
• ITER is an international fusion energy project based in France.