TECHNOLOGY DEVELOPMENT FOR RECIRCULATING HEAVY-ION ACCELERATORS

The << recirculator >>, a recirculating heavy-ion accelerator, has bee n identified as a promising approach for an inertial-fusion driver. Sy stem studies have been conducted to evaluate the recirculator on the b asis of feasibility and cost. The recirculator has been shown to have significant cost advantages over other potential driver schemes, but s ome of the performance requirements exceed the capabilities of present technology. The system studies identified the high-leverage areas whe re advances in technology will significantly impact the cost and perfo rmance of a recirculator. One of the high-leverage areas is the modula tor system which generates the acceleration potentials in the inductio n cells. The modulator system must be capable of generating the accele ration potentials at peak repetition rates in excess of 100 kHz with v ariable pulse widths. LLNL is developing a modulator technology capabl e of driving induction cells using the latest in solid-state MOSFET te chnology. A small-scale modulator has been built and tested to prove t he concept and the next version is presently being designed. Our objec tive is to demonstrate a modulator operating at 5 kV, 1 kA, with 0.2-1 pulse widths while driving an induction cell at > 100 kHz within the next year. This paper describes the recirculator, the technology requi rements necessary to implement it and the modulator system development that is being pursued to meet these requirements.