Simulation of Perturbed Motion of a Very Low Earth Orbit Spacecraft with a Corrective Variable-Magnitude Thrust Electric Propulsion System

This paper presents an approach to modeling the perturbed motion of a low-orbit spacecraft equipped with a corrective electric propulsion system operating in adaptive thrust control modes. The approach is based on a specified criterion for maintaining an ultra-low orbit while taking into account the existing operational time constraints. The proposed mathematical models are intended for numerical calculations and can be applied in design analysis tasks, particularly when the mass–dimensional and energy characteristics of an ultra-low-orbit spacecraft and its electric propulsion system are to be selected jointly. The model enables the evaluation of key design parameters, such as the propellant mass flow rate and the energy consumption profile of the electric propulsion system for a given vector of discrete scalar thrust values, as well as the profiles of operational time constraints (per orbit, per day, or over a long-term interval). Furthermore, the model facilitates the development of solutions for selecting the design and ballistic parameters of very-low-orbit small spacecraft, together with the adaptive parameters of the electric propulsion system—consistent with the operational mode restrictions—based on discretely adjustable thrust levels corresponding to the actual characteristics of existing hardware prototypes.