Simulation and Modeling of Prompt Electrical Tree Formation During Dielectric Breakdown in Space-Charged Dielectrics

This talk outlines the development and validation of a simulation model to depict nanosecond-scale electrical tree formation and discharge within a dielectric. Electrical treeing is a principal degradation mechanism in polymeric insulation materials that culminates in catastrophic failure in high-voltage equipment. Dielectric materials have advantageous insulating properties and are lightweight, making them useful in aerospace applications. However, the possibility of discharge failure due to electrical treeing poses a substantial risk and can lead to a shortened operational lifetime. This can lead to mission-critical malfunctions, jeopardizing not only expensive equipment but also the overall mission objectives and, in crewed missions, the safety of astronauts onboard. Due to this inherent increase in risk, more complex construction methods of antennas and electronics must be used, leading to increased mission costs. This motivates the development of a simulation environment that can characterize dielectric performance in radiation environments. The simulation results, including discharge current waveforms and electrical tree growth parameters, are compared to experimental results produced under identical conditions to the simulation. By implementing an RLC framework and pulse-forming network to model the electrical characteristics of the breakdown, the simulation produces results that qualitatively agree very well with the experiment. The model shows the promising predictive power of electrical treeing in space-charged dielectrics, essential for mitigating this detrimental effect in dielectrics in charged particle radiation environments, such as satellites and spacecraft.