Operation of the TFTR neutral beam injection system which achieved greater than 30 megawatt injection

The Tokamak Fusion Test Reactor (TFTR) neutral beam injection system (NBIS) has performed injection experiments on the TFTR since 1984. During the 1988 run period, the NBIS exceeded the design capability of 27 MW of neutral injection. How the NBIS was operated to yield 30.5 MW of injected neutrals, the equipment upgrades and operational improvements from the 1987 operating experience which contributed to achieving this result, and the techniques used to achieve substantially increased system reliability over the 1987 run period are discussed