A Framework for Peak Power Exceedances of High Power Microwave Radiators Applied to a Vircator Surrogate Model

Abstract

Uncertainty quantification and variability analysis are two domains of interest when looking at the efficiency of HPEM sources. Vircator is known to be a low efficiency high power microwave source subject to several generally volatile phenomena such as plasma expansion and shot-to-shot variability. In this study, a computationally low cost framework combining the Extreme Value Theory (EVT) and the Generalised Design of Experiments is proposed in order to study the peak power distribution of a Vircator obtained with a surrogate model. Following the pre-screening of random variables, the optimised parameters are introduced in 2.5D and 3D simulation tools, namely XOOPIC and CST-PS. It has been confirmed that the peak power output can reach a 40% increase. This shows that the EVT proves to be successful in classifying and quantifying random variables to influence the distribution tails.

Exploring the Impact of Scaling Variations of Virtual Cathode Oscillators on Frequency and Efficiency

“…Moza Mohamed (1) *, Mae AlMansoori (1) (2) , Ernesto Neira (1) , Felix Vega (1) , and Chaouki Kasmi (1) (2) (1) Directed Energy Research Center, Technology Innovation Institute, Abu Dhabi, UAE; e-mail: moza.mohamed@tii.ae (2) Faculty of Electrical Engineering, Helmut Schmidt University, 22043 Hamburg, Germany; e-mail: mae.almansoori@tii.ae…”

“…Recently, the authors published a surrogate model allowing the estimation of the peak power output (𝑝 𝑝 ) and the radiating frequency (𝑓) of an axially extracted Vircator [2].…”

“…In particular, we are interested in the cases where the scale factor s<1. As starting point (baseline) we'll use the model published in [2], which has a central frequency 𝑓(1) = 7.2 GHz, and an efficiency of 𝑒 𝑓 (1) = 0.98%. The results allow us to conclude that the efficiency is not immune to isotropic scale variations.…”