Tokamak à configuration variable

Tokamak à Configuration Variable (TCV): inner view, with the graphite-clad torus. Courtesy of CRPP-EPFL, Association Suisse-Euratom

Tokamak à Configuration Variable (TCV): general view of the setup. Courtesy of CRPP-EPFL, Association Suisse-Euratom

The Tokamak à configuration variable (TCV, literally "variable configuration tokamak") is a research fusion reactor of the École polytechnique fédérale de Lausanne. Its distinguishing feature over other tokamaks is that its torus section is three times higher than wide. This allows studying several shapes of plasmas, which is particularly relevant since the shape of the plasma has links to the performance of the reactor. The TCV was set up in November 1992.

Characteristics

• Plasma height: 1.40 metres
• Minor radius: 0.25 metre
• Major radius: 0.88 metre
• Plasma current: 1.2 megaamperes
• Plasma life span: 2 seconds maximum
• Toroidal magnetic field: 1.43 teslas
• Additional heating power: 4.5 megawatts

Main studies

• Confinement studies
  • confinement as a function of the shape of the plasma (triangular, square or elongated)
  • Improvement of the confinement of the core
• Studies on vertically elongated plasmas
• Studies with ECRH and ECCD (electron cyclotron resonance heating and electron cyclotron current drive)

By 2012 it had 16 poloidal plasma shaping coils and could achieve a variety of field configurations and plasma shapes.

History

• 1976: First proposal for an elongated tokamak by the "New Swiss Association"
• 1985: Second proposal, with a more elongated tokamak
• 1986: Acceptance of the TCV proposal (Tokamak à Configuration Variable)
• 1992: First plasma discharge
• 1997: World record of plasma elongation (see plasma shaping)
• by August 2015 it has had a 19-month shutdown/upgrade to install its first neutral beam injector.
• by 2016 it was upgraded/enhanced to run with a 'snowflake' divertor

External links

• TCV official site
  • TCV Technical data as of Oct 2012