Studied on the electrons collected by bare conductive tether applied to electrodynamic tether

The electrodynamic tether technology is a new method for space propulsion. When an electrodynamic tether runs on a low-Earth-orbit, a bare conductive tether with current flow will interact with the geomagnetic field to generate Lorentz force exerted on the tether. To generate current in the long conductive tether, the electrodynamic tether should exchange electrons with the surrounding space plasma. In the process of electrons exchange, electrons are collected from space plasma by the bare conductive tether. Almost all the existing studies took the orbital motion limited theory to describe the process of electrons collection and calculate the value of current in the tether, but the orbital-motion-limited theory is insufficient when some non-ideal situations are considered, such as the flow rate of the surrounding plasma, the cyclotron motion of electron effected by geomagnetic field, and the irregular shape of tether, etc. In this work, a complicated analytical model of electrons collection is firstly established based on the Spacecraft Plasma Interaction Software (SPIS). The values of current in the conductive tether effected by non-ideal factors are calculated. The analytical model is used to correct the value of orbital-motion-limited current. A de-orbiting dynamics model of electrodynamic tether including the analytical model of electrons collection is then established. The variation of de-orbiting dynamics of electrodynamic tether under the effects of non-ideal factors is studied.