Subscribe options

Select your newsletters:

Please enter your email address:

@

Your email address will only be used for the purpose of sending you the ITER Organization publication(s) that you have requested. ITER Organization will not transfer your email address or other personal data to any other party or use it for commercial purposes.

If you change your mind, you can easily unsubscribe by clicking the unsubscribe option at the bottom of an email you've received from ITER Organization.

For more information, see our Privacy policy.

News & Media

Latest ITER Newsline

  • Fusion world | Mobilizing for long-pulse operation

    One of the key operational challenges in the development of fusion energy is the achievement, simultaneously, of high fusion performance and long-pulse operatio [...]

    Read more

  • ITER science | What is burning plasma?

    The dream of fusion power depends first and foremost on a self-sustaining fusion reaction, with most of the heating power needed coming from within the reaction [...]

    Read more

  • Plasma modelling | New SOLPS-ITER code version launched

    The widely used SOLPS-ITER tool for plasma edge modelling has evolved since its launch in 2015. At recent workshop at KU Leuven in Belgium, European specialists [...]

    Read more

  • Open Doors Day | Accessing the very heart of ITER

    Small or tall, knowledgeable or neophyte, from near or far ... the 600 people who took part in ITER's latest Open Doors Day all departed with the sense that som [...]

    Read more

  • Local | A question and answer session

    Nuclear safety policy in France requires that a local information commission (Commission locale d'information, CLI) be established every time a nuclear installa [...]

    Read more

Of Interest

See archived entries

Plasma heating

Japan completes gyrotrons

To achieve extreme temperatures in the core of the plasma, ITER will rely on three external heating systems. One of them—electron cyclotron resonance heating—relies on the electromagnetic-wave-generating power of 24 slim, silver gyrotrons. Gyrotrons have been in development for decades as scientists worked to bring their performance to the levels required at ITER. Now, high-power, high-frequency gyrotrons are a reality.

Japan's QST Institute (National Institutes for Quantum and Radiological Science and Technology) has manufactured eight high-power microwave sources, called gyrotrons, for ITER's electron cyclotron resonance heating system. Factory acceptance testing has concluded successfully on the four units that are required for ITER's First Plasma. These units are ready to ship. (Click to view larger version...)
Japan's QST Institute (National Institutes for Quantum and Radiological Science and Technology) has manufactured eight high-power microwave sources, called gyrotrons, for ITER's electron cyclotron resonance heating system. Factory acceptance testing has concluded successfully on the four units that are required for ITER's First Plasma. These units are ready to ship.
Of the 24 required gyrotrons, Japan has been tasked by the ITER Organization with fabricating 8. The National Institutes for Quantum and Radioactive Science and Technology (QST) and Canon Electron Tubes & Devices Co., Ltd. (CETD) have completed the full manufacturing scope, and the four gyrotrons required for installation before First Plasma have passed all testing.

QST and CETD began the research and development of gyrotrons in 1993, and by 2008 they had developed the world's first gyrotron satisfying ITER's power requirements. After further adjustments to increase the durability of the gyrotrons, manufacturing began and the eight devices assigned to Japan were completed in May 2021.

Before the gyrotrons can be shipped to France, they must undergo rigorous performance tests. The gyrotron must withstand prolonged use under intense conditions and generate enough power to heat the plasma and maintain efficiency. Gyrotron testing at ITER requires electrical efficiency of more than 50% (50% of input electric energy converted to electromagnetic-wave power), and the success rate of repeated gyrotron operation must be at least 90%.

Now that four of Japan's gyrotrons have passed testing, plans are being made to transport them from their nests at QST to the ITER complex. The ultimate goal is to have all eight gyrotrons on site by 2024.

Once the gyrotrons arrive, they will be installed as part of the electron cyclotron resonance heating (ECRH) system, one of three methods (alongside neutral beam injection and ion cyclotron heating) ITER will use to heat plasma to its required temperature. ECRH works by heating electrons through intense beams of electromagnetic radiation, which can be directed to heat specific areas of plasma as needed.

The gyrotrons wait in their boxes now, cool and silent in their dormancy. But soon, as pieces of the ITER machine come together, they will hum with energy and ignite First Plasma.

Please see the original press release in Japanese.

Read more about the ITER gyrotrons here.



return to the latest published articles