On the Design of Power and Propulsion Subsystems of All-Electric Telecommunication Satellites

Abstract

High power budget of telecommunication spacecraft can potentially allow the operation of multiple electric thrusters simultaneously during an orbital transfer to the Geostationary Earth orbit. In this paper, we consider the problem of electric orbit-raising during which the spacecraft uses more than one thruster type during the transfer. We develop a methodology to determine trajectories from arbitrary starting orbits to the GEO for the case when two different thruster types are used during the maneuver. We also develop a framework to analyze the solar array degradation caused by protons in the Van Allen radiation belts during orbit-raising. We demonstrate our methodology with the help of numerical examples that evaluate the trade-offs associated with using arcjets during the initial part of the transfer. We consider different cases of switching from arcjets to Hall thrusters during the maneuver and evaluate the requirements on shielding thickness in order to limit the radiation exposure for representative orbit-raising trajectories. Nomenclature x, y, z components of the position vector of a spacecraft r P periapsis of the instantaneous orbit of a spacecraft u radial velocity of the satellite v transverse velocity of the satellite w out-of-plane velocity component of the satellite m mass of the satellite T thrust magnitude α, β direction of the thrust vector of the satellite D d displacement damage dose t ffinal time for the orbit-raising maneuver µ gravitational parameter for the Earth R E radius of the Earth ∆P deg solar array degradation Ψ P flux of protons at a location in space Φ P fluence of protons of energy-level E along a trajectory E energy levels of incident protons E energy levels of transmitted protons T max maximum thrust provides by the electric thruster n i number of thrusters of type i T i thrust provided by a specific thruster of type i Subscripts:i Index number of thruster type

Dynamic Co-Kriging Method Using Probability of Multi-Objective Constrained Improvement for Aerospace System Optimization

“…And the time step for simulation is set to be 120 seconds to guarantee the propagation accuracy. The NASA AP8 model [48] is used to compute the displacement damage dose as the radiation damage; as for the LF transfer model, the orbital averaging technique [49] is used to solve the motion equations. And the perturbations and eclipses are ignored.…”

A Concept Study of the All-Electric Satellite’s Attitude and Orbit Control System in Orbit Raising

“…To resolve this problem, it is necessary to optimize satellite orbit and attitude control, into which substantial research has already been conducted [4][5][6], [9][10][11][12][13][14].…”