Solid-state pulsed power systems for the Next Linear Collider

The Next Generation Linear Collider (NLC) represents a significant challenge for high voltage modulator technology. It will require pulse modulators capable of driving over 1600 NLC klystrons at 500 kV, approximately 265 A apiece, with 3.2 microsecond pulses at 180 Hz. These pulses also have strict tolerances for flattop and voltage regulation. Average klystron input power for the complete NLC system is approximately 120 MW-representing $6-12M or more per operating hour. All losses in the power systems between the utility and the klystron must be added to this power cost, making efficiency of these systems paramount. Given the large number of modulators required and the total cost of power for the NLC, overall life cycle costs, not just the initial equipment cost, will be a significant factor in the affordability of the NLC. DTI's efforts are focused on three modulator configurations: a "hybrid modulator", using a solid-state switch and a pulse transformer, and two transformerless designs, one based on a 500 kV hard switch, and a second based on solid-state Marx bank. Each of these is discussed in this paper.