Experimental Research on Solar Array Drive Assembly Internal Charging Effects

Solar Array Drive Assembly (SADA) is a crucial component of the electrical transfer sub-assembly of the modern long life and large power satellite. The internal discharging and secondary arc in SADA, which happened under the high-energy electron environment, can lead to spacecraft abnormity and malfunction. Experimental platform has been built by using the two-beam accelerator. In the experiment, the electron energy is 2MeV, the beam density is 5pA·cm^-2, the working voltage of SADA is from 50 to 150V, and the working current is from 0.5 to 1.5A. The charging potential of test sample can reach equilibrium after 5 hours of irradiation. The electric field can reach about 5×10⁶V·m^-1. The time of discharge increases apparently with the increase of the working voltage at the same operating current. It shows that the electric field formed by the working voltage and the electric field formed by the high energy electron deposition will be superposed, which leads to the increase of the risk of SADA discharge. According the experiment results, the design of SADA anti-internal electricity can be improved by adopting the following methods. By reducing the bulk resistivity of SADA dielectric disk and improving the design of conducting ring structure, the electric field on the dielectric disk formed by the voltage between the conductive rings can be reduced.