Influence of Gamma Radiation on Gas-Filled Surge Arresters

Current knowledge on the impact of γ radiation on gas-filled surge arresters (GFSA) is presented. Miniaturization of electronic components has led to their increased vulnerability to overvoltage. The combination of ionizing radiation and voltage surges is present in both space exploration and military applications. Some of the commonly used overvoltage protection components (transient suppressor diodes and metal-oxide varistors) perform poorly under ionizing radiation. GFSA demon-strate improved performance under γ irradiation. Performance of GFSA was tested under neutron + γ radiation, considering the effects of induced radiation. The effects of γ radiation were tested on commercially available GFSA components and on the purpose-built GFSA model. The model was used to measure the prebreakdown current and breakdown voltage of different electrode materials (aluminum, steel, brass) under varying gas pressures, under DC and pulse currents. The improvement of the performance of GFSA due to external γ radiation, combined with other improve-ments in the design (hollow cathode), can enable the use of GFSA without internal radiation sources in environments where γ radiation is present.