Thruster Performance Analysis of Hall-effect Thruster by Orbit Evolution

Abstract

The satellite's separated orbit is different to objective orbit. And the altitude of the earth observation satellite decreases from the desired orbit because of the atmospheric drag. To compensate for this, the separation orbit error and the altitude decrease, earth observation satellites have been equipped with a propulsion system. Hall-effect thruster is a type of Ion thruster in which the propellant is efficiently accelerated by an electric field to produce the thrust force. Due to the nature of high specific impulse with extremely small fuel amount, Hall-effect thrusters are very useful for small satellite's orbit maintenance. The thrust force of Hall-effect thruster developed in Satrec Initiative is very low as 11mN and the Hall-effect thruster is implemented for the orbit altitude maintenance of Dubaisat-2 which is a 1-m resolution remote sensing satellite operating in 600-km low earth orbit. Thrust efficiency of Hall-effect thruster operated in orbit can be found in the relevant parameters such as the fuel tank pressure and thruster voltage. However, the actual thrust performance should be confirmed by analyzing the orbit evolution. The analysis of the thruster performance is comparatively difficult because its thrust force is very small. In this paper, analytical studies for the Hall-effect thruster performance estimation based on orbit evolution are presented to verify its effectiveness. And thrust firing epoch and thrust efficiency are analyzed by calculating orbit evolution. To verify the suggested scheme, simulation is performed and the effectiveness is confirmed. In particular, the analysis is performed using GPS receiver's navigation solution of Dubaist-2 and the authors verify its effectiveness comparing it to HEPS parameters for firing epoch and thrust force. As a result, the presented method can successfully detect the thrust firing epoch and the thrust. NomenclatureGPS = Global Positioning System LPE = Lagrange Planetary Equations SMA = Semi-Major Axis HPOP = High Precise Orbit Propagator HEPS = Hall Effect Propulsion System