The design of highly reliable RF system for high power linacs

Abstract

Possibility of substantial reliability growth of high intensity linear ion accelerators, for solving of a number of nuclear power engineering problems is considered. A way of uninterrupted maintenance accelerating RF field in a Main Part of such Accelerators -MPA, where particles receive the main part of energy is suggested. If each section of MPA contains 1-3 accelerating gaps and is excited from separate RF channel, the failure of one or even several channels will not destroy the resonant acceleration. Besides of that it is easy to compensate the acceleration shortage (on time of channel repair) by small automatic increase of accelerating field strength in the rest operating sections. The great quantity of sections from a disadvantage is transformed into advantage because failure-free MPA operation can be maintained. In the report quantitative estimations for the method suggested and its comparison with variants of RF channel reserve are presented. RF feeders efficiency 0.9 Channel RF power reserve for control RF power for one cell Total RF power of all output stages 15 % 70 kW 160 MW 2. RF SYSTEM WITHOUT RESERVE CHANNELS At a steady state of long operation in absence of a reserve (Fig.l.1) relative idle time of the whole system-T, and the average time of its operation to a refusal -T, is: where: & -average restoring time of a single RF channel serviceability; tp -average operating time of single channel to a refusal; N -the number of working RF channels (each channel contains the whole equipment, ensuring exciting of RF power, including the rectifier as well as control, interlock and signalling systems) [ 6 ] . TD = tR/(TC + tR) ; T, = tF/N ;

IFMIF accelerator facility RAMI analyses in the engineering design phase

“…To overcome these dependability challenges, studies [56] and design proposals [57] have been done to improve the reliability for future designs. Studies about fault-tolerant designs with fast tuning and recovery procedures have been done, together with gathering best practices from other facilities, to decrease the number of beam trips as much as possible [58][59][60][61].…”