Princeton's Symmetrical Tokamak from Proposal to Plasma in 8 Months

Although the original design of the Model C Stellarator facility allowed for a great amount of flexibility with a "race-track" geometry, conversion to the circular geometry required for the Symmetrical Tokamak presented a number of special engineering problems. This paper summarizes and details the various changes required to meet the Tokamak concept including: major machine operations on the structural members of the stellarator, addition of confining field coils and special vertical field loops, a copper liner used for plasma stabilization, the new and larger diameter vacuum system and finally the changes in the ohmic heating coupling transformers.