Marx Modulator Optimization for Advanced Accelerators

The next generation of particle accelerators will require large numbers of RF cavities, producing field gradients undreamt of a dozen years ago. The next frontier is high energy, short pulse modulators, continuing the technical thrust begun under recent colliders and numerous X-Band accelerator designs. Modulators to drive the klystrons for these new accelerators must meet aggressive requirements for pulse risetime, flatness, and repeatability requirements, at hundreds of kV. For short-pulse modulators, the Marx topology provides a means to achieve astounding risetimes and flattop control that are simply not available with hybrid (switch / pulse transformer) topologies. The basic proof of principle of solid-state Marx architectures has been demonstrated by several organizations, but deployable solutions for high voltage, short-pulse accelerators have not been available as of yet. In our Phase I effort, we have demonstrated a prototype Marx modulator design with the performance, affordability, and reliability necessary for this new class of accelerators. This proposed effort is focused on advancing the Marx modulator design developed in Phase I from a prototype to a fully functional, installed system for the 500 kV operation of a magnicon tube. Commercial Applications and Other Benefits: A key benefit of this SBIR effort, therefore, is to reduce the cost of solid-state modulator designs significantly, allowing them to finally undercut the cost of conventional designs, while providing higher levels of pulse control, reliability, and efficiency. RF systems, primarily the klystrons and modulators, typically account for over one-third of the construction cost of a new accelerator. A significant reduction in modulator costs, therefore, has an appreciable impact on the price tag for any accelerator.