航天器太阳电池阵驱动机构导电滑环真空充放电实验研究

太阳电池阵驱动机构部分暴露在航天器舱体外，其内部导电滑环容易成为充放电效应的侵害对象，利用90Sr-90Y β放射源模拟中高地球轨道的高能电子环境，实验研究不同辐照强度下导电滑环的充放电过程。结果显示：辐照初始阶段发生幅值较小的放电，多数为表面放电；随着电位升高，深层充电导致材料内部积累大量电子，超过一定阈值之后，发生击穿放电。导电滑环在2.4 pA/cm2通量的电子辐照下，其充电平衡电位达到-3600 V；而在0.1 pA/cm2通量下，平衡电位仅为-300 V。建议增加3 mm厚防护铝板以降低高能电子通量，预防导电滑环因充放电造成故障。在辐照实验过程中，同时监测导电滑环工作状态，未发现异常，说明在短时间辐照中发生的放电对导电滑环工作性能没有影响。

Experimental study of vacuum charge and discharge of the slip ring in spacecraft solar array drive mechanism

The solar array drive mechanism is partially exposed to the outside of the spacecraft, and the slip ring is easy to become the victim of the charge and discharge effect. The charging and discharging process of the slip ring under various radiation intensities is studied by using the 90Sr-90Y β source to simulate the high-energy electron environment in the middle and high Earth orbits. In the initial stage of the irradiation, the discharge of small amplitude is mostly the surface discharge. With the increase of the potential, the deep charging leads to the accumulation of a large number of electrons in the material. Beyond a certain threshold, the breakdown discharge occurs. Under the electron irradiation of 2.4 pA/cm2 flux, the charging equilibrium potential of the slip ring reaches -3600 V, while under the 0.1 pA/cm2 flux, the equilibrium potential is only -300 V. It is recommended to add a 3 mm protective aluminum plate to reduce the high-energy electron flux, to prevent the fault caused by charging and discharging of the slip ring in orbit. During the irradiation test, the working state of the slip ring is determined, with no abnormality being found. This indicates that the discharge during a short time irradiation has no effect on the performance of the slip ring.