H-1NF: The National Plasma Fusion Research FacilityHelical plasma(Argon)Helical conductor control winding5 tonne support structureRotating 55 view Doppler tomography systemRotating 64 wire electron beam tomography systemDiamagnetic energy monitorPentagonal central support column14000Amp bus conductor and coolingby Ding-fa ZhouPhotos: Tim Wetherell12MW Pulsed Magnet Power SupplyDC-DC Convertor/Regulator: ABB Aust. /Technocon AG 24 Pulse Rectifier: Cegelec Australia Transformers/Reactors: TMC Australia Switchgear: Holec Australia and A-Force Switchboards, Sydney Consultant Engineers: Walshe & Associates, Sydneyfish-eye view of corrugated ECH waveguide to H-1 on left.(H.Punzmann)ECH plasmaThe figure shows an ECH produced plasma (200kW 28GHz gyrotron, 2CE at 0.5T). With a 10ms pulse, and rf preionization of ~11017m-3, a diamagnetic temperature of 100-200eV was observed provided gas feed was carefully controlled (p < 210-6 Torr). A highly localised ionization rate was observed in the emission from argon doping, and at higher gas fills, a peak density in excess of 31018 was obtained, with a lower temperature. Impurity levels, estimated by comparison of spectral line intensities, were lower than in the rf discharges.Microwave Source:(Kyoto-NIFS-ANU collab.) 28 GHz gyrotron 230 kW ~ 40msThe H-1 heliac is a current-free stellarator with a helical magnetic axis which twists around the machine axis (a 1m circular ring conductor,) three times in one toroidal rotation. It is a flexible heliac composed almost entirely of circular coils with the exception of the helical control winding, which also wraps around the ring conductor, in phase with the magnetic axis of the plasma. Control of this current produces a range of rotational transform from 1 to 1.5: (B0 =1T, r > 0.15-0.2 m), and 0.7 to 2.2 for B0 ~ 0.5 T, r > 0.1 m, allowing almost independent control of two of the three parameters: , magnetic well (2% to +6%) and shear in rotational transform., which can be positive (stellarator-type) negative (tokamak-like), or near zero (