3-D Simulation Study on Deep Dielectric Charging Characteristics of Satellite Slip Ring Assembly

Deep dielectric charging and discharging effects significantly contribute to the failure or abnormal operation of geosynchronous orbit (GEO) satellites. In this article, aiming at the deep dielectric charging problem of satellite complex structures, based on the charge conservation law and the conductivity–temperature model, a 3-D simulation time-domain model is developed to investigate the deep charging of the solar array drive assembly (SADA) slip ring. The model utilizes a combination of Monte Carlo particle transport simulation and finite-element calculation. It takes into account the influence of medium conductivity, temperature, and shielding thickness. The simulation results demonstrate that under the worst energy spectrum radiation environment of GEO, the most serious part of deep dielectric charging in the SADA slip ring is the junction of the upper edge of the metal conductor and the insulating medium. With the increase in shielding thickness, the deep dielectric charging effect is weakened, but with the decrease in temperature, the shielding effect is significantly reduced. When the temperature is 253 K, the radiation-induced conductivity plays a dominant role; even with a shielding thickness of 3.5 mm, the maximum electric field intensity remains close to the breakdown threshold of
$2\times 10^{7}$
V/m, making it susceptible to internal discharge. The conclusions can provide valuable theoretical guidance for deep charging research and shielding design of satellite complex structures.