[Table of Contents]

Plasma and Fusion Research

Volume 7, 2405051 (2012)

Regular Articles

Conceptual Design of DC Power Supplies for FFHR Superconducting Magnet
Hirotaka CHIKARAISHI and FFHR Design Group
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan
(Received 7 December 2011 / Accepted 21 March 2012 / Published 07 June 2012)


The force-free helical reactor (FFHR) is a helical-type fusion reactor whose design is being studied at the National Institute for Fusion Science. The FFHR will use three sets of superconducting coils to confine the plasma. It is not a fusion plasma experimental device, and the magnetic field configuration will be optimized for burning plasma. This paper introduces a conceptual design for a dc power system to excite the superconducting coils of the FFHR. In this design, the poloidal coils are divided into a main part, which generates a magnetic field for steady-state burning, and a control part, which is used in the ignition process to control the magnetic axis. The feasibility of this configuration was studied using the Large Helical Device coil parameters, and the coil voltages required to sweep the magnetic axis were calculated. It was confirmed that the axis sweep could be performed without a high output voltage from the main power supply. Finally, the power supply ratings for the FFHR were estimated from the stored magnetic energy.


dc power supply, fusion reactor, FFHR, superconducting magnet

DOI: 10.1585/pfr.7.2405051


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This paper may be cited as follows:

Hirotaka CHIKARAISHI and FFHR Design Group, Plasma Fusion Res. 7, 2405051 (2012).