Development of a prototype KSTAR neutral beam system

A prototype KSTAR neutral beam (NB) system has been developed to test the long pulse operability of the KSTAR NB system for 300 seconds at the designed beam power. The prototype system consists of an ion source, beam line components, power supplies, water-cooling circuits, and a control & DAQ system. The ion source was designed to extract a 120 keV, 65 A deuterium beam with a rectangular beam size of 13 x 48 cm(2). The beam line components include a neutralizer, a bending magnet, ion dumps, a calorimeter, and cryo-sorption pumps. An acceleration power supply, an arc power supply, a filament power supply, and a deceleration power supply provide the necessary powers in proper timings to the ion source. Data acquisition modules controlled by LabVIEW software acquire more than 200 data points from the thermocouples, flow meters, and others. The water cooling system can support experiments with a 2-MW continuous beam and can be extended to support experiments with an 8-MW beam for 300 seconds. The necessary tests of the prototype system have been done with high-power, long pulse beams.