Trade-off studies for CIT PF power supply configuration

Reducing the total number of supplies to power the poloidal field coils is of major concern in the proposed CIT device. Because of the limited number of existing power supplies now in use on TFTR, a considerable engineering study is justified to effect this saving. This paper describes and analyzes various circuit configurations which can be utilized to maximize the capabilities of the individual modules. In particular, consideration is given to a circuit connection with synchronizes the switching of the coils to insure coordinated currents in the coils used for plasma startup where, of necessity, the stray field in the plasma region must be minimized. Additionally, several switching schemes are described which accommodate differing dynamic circuit conditions and examples are presented which show the circuit flexibility available to maximize each power supply module capability using these switching configurations