NLC Marx Bank Modulator

73028-The Next Generation Linear Collider (NLC) will require high voltage pulse modulators to drive thousands of NLC klystrons at 500 kV, 265 A each. The cost of building and operating these systems represents a substantial segment of the overall NLC cost. In order to reduce the capital, operating, and power costs of these systems, the DOE is investigating a range of modulator technologies and architectures to identify and validate the optimal combination of performance, cost, and efficiency. In previous work, a solid-state Marx Bank modulator, a design with the potential to provide significant cost and efficiency improvements over other modulator architectures, was investigated. The design eliminates the pulse transformer associated with other modulator designs, which avoids large power losses and translates to savings of nearly $100M in electricity costs over a 10 year operating period. This project will design and build a full scale, solid-state NLC Marx bank modulator. Phase I designed and prototyped two variants of a solid-state Marx Bank modulator ¿ one based on discrete IGBT devices, and one based on series connected IGBTs. For both designs, performance was extrapolated to full NLC capability through circuit modeling. In both cases, the solid-state Marx Bank designs proved to be significantly more efficient than alternative NLC modulator designs. The series-connected design also offered the potential to eliminate two levels of losses in the power supply itself, increasing the overall system efficiency by another 5%. Phase II will build and test a 500 kV, 530 A, solid-state Marx Bank modulator and its associated power supply. The system will have low construction cost, high efficiency, a small footprint, and a capability of driving two NLC klystrons. The system will be delivered to SLAC for assessment and operation. Commercial Applications and Other Benefits as described by awardee: The solid state Marx Bank modulator should have numerous applications in commercial and military high voltage systems, including commercial accelerators for medical treatment and inspection systems, military and commercial radar transmitters, and a range of materials modification processes. The small size, efficiency, and low cost of this approach will significantly speed the adoption of solid-state pulsed power systems in these markets.