Sandia Labs FY22 Laboratory Directed Research & Development Annual Report

FY22 ANNUAL REPORT

DEVELOPMENT OF HYBRID SYSTEM-COMPONENT MODEL DEVELOPMENT FOR LOW-COST HIGH-ALTITUDE EMP TESTING.

This LDRD project developed a methodology for modeling cable configurations in a substation or generation plant circuit to predict high-altitude electromagnetic pulse (HEMP) propagation through a system. This approach seeks to address gaps in how HEMP vulnerability assessments are performed by enabling better prediction of threat environments at critical equipment, which

is vital for cost-effective mitigation planning. The one-year effort of this project focused on defining the methodology for a termination cabinet example case supported by experimental data and focused EM field modeling of cabinet features. It was discovered that transmission line models defining cables with respect to the nearest ground metal were well aligned to experimental data, and that many

typical features of cabinet configurations were too small to significantly impact conducted HEMP propagation. The process used in this work can be applied to build model libraries in a future vulnerability assessment tool. (PI: Tyler Bowman)

Comparison between experimental data from current viewing transformers (CVT) and circuit simulation of a termination cabinet with (top) a high output impedance or (bottom) a low output impedance.

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