A Fet-Switched Induction Accelerator Cell

Abstract

An array of 24 field-effect transistors (FETs) is being used to switch a nominal 4-kV, I-its pulse onto a Metglas induction core at pulse rates exceeding 100 kHz. Each transistor receives isolated gate power from a de/de converter and analog pulse control via an optical fiber. The array is part of a specialized circuit architecture that generates bursts of pulses while providing for core reset between pulses. The circuit will accommodate variations in pulse width, repetition frequency (prf), pulse amplitude, burst length and reset interval. The various circuit elements are assembled directly onto the core structure to yield a compact, low-impedance package.Two prototype machines are presently under development. A 24-FET machine is :.n operation and capable of 4.2-kV, 1-its pulses (max.) at a 120-ktlz prf for short bursts. Pulse rise and fall times are 25 ns and 65 ns respectively. A 128-FET machine is under construction which should be capable of 6-kV, 1-its pulses (max.) at a 150-kHz prf for long bursts.

Progress toward a prototype recirculating induction accelerator for heavy-ion fusion

“…The small recirculator will have a .circumference of 14. 4 meters, a 3.5 cm aperture radius (pipe radius) for the beam focusing and bending elements, and a half-lattice period.of 36 cm. The beam wilI be transverseIy focused .…”

“…Later experiments will study Present technology has achieved 200 kHz bursts at 5 kV and 800 A with pulse widths of 0.5-2 ms, but with a nonvariable format. [4] Because of its long (~200 km) beam path length and the,fact that the beam repeatedly visits each section of the beam line, a recirculator driver will require a vacuum of-10-10 to 10-11 torr.…”