Commissioning of the Lower Hybrid Current Drive System on Alcator C-Mod

A lower hybrid current drive (LHCD) system has been developed for current profile control of advanced tokamak experiments on Alcator C-Mod. LHCD along with Ion Cyclotron Radio Frequency (ICRF) heating will be used to develop regimes with high confinement, high beta
_n
and high bootstrap fraction and extend them to quasi-steady-state conditions. This paper will describe the commissioning and initial operation of the LHCD system that includes a 50 kV, 208 A pulsed-power supply, twelve 250 kW Klystron transmitters, a 96 waveguide launcher and required control, protection and data acquisition systems