The ZR Final Design Pulsed Power Performance Expectations

The largest X-ray generating facility in the world (~1.8 MJ), the Z machine at Sandia National Laboratories (SNL), is presently undergoing a major upgrade. Upon completion of its refurbishment, ZR is expected to deliver an output current of 26 MA to a standard 20 mm by 40 mm diameter Z-pinch load with a 100-ns implosion time. In addition to nearly doubling the output energy and providing a useful increase in current capability to the research community, the Project criteria include providing an enhanced precision, improved timing jitter, and advanced pulse shaping flexibility needed for full parameter space assessment for the material science community. Another criteria is to increase the shot capacity by enabling the facility and diagnostics infrastructure to routinely support 400 shots per year while minimizing the impact of implementing improvements on existing experimental programs. The Project´s objective of extending the life of Z in a balanced way also served to exercise SNL´s pulsed power research and engineering capabilities and resources and retain the expertise that will be required for future endeavors. This paper summarizes the predicted pulsed power performance of the 36-module ZR from the 577-kJ (at 85-kV charge) Marx generators in the oil energy storage section through the water pulse forming section components and the vacuum section to the Z-pinch load. Comparisons show good agreement between the most recent models and experimental results from full-scale, single module systems which are very similar to the final design. Discussions will emphasize the laser triggered gas switches and the self-break water switches which are continuing to be optimized