ANALYSES OF EARTH OBSERVATION AND TELECOMMUNICATIONS MISSION SCENARIOS WITH SMALL HALL EFFECT THRUSTERS PROPULSION

摘要

The ESA-funded study on "Combined Telecommunication and Earth Observation Mission driven Option For Small Hall Effect Thrusters (HET) Propulsion" has been carried out with the primary aim to assess the application of a small-HET technology in the frame of Earth Observation (EO) and telecommunications missions. The study is intended to outline a complete set of performance requirements imposed on the new small-HET system by a wide spectrum of missions, focussing on the assessment of thrust level, in-orbit lifetime and total impulse needed.The analysis of LEO EO missions highlighted that a thrust demand in the 2-20 mN range is typically needed to fulfil the manoeuvre requirements for drag compensation or to enable drag-free conditions. A fine-tuning of mission altitude and lifetime, as well as thrusting time, yields a total impulse that complies with the expected small-HET performance. Small GEO telecommunication platforms, with a typical thrust demand in the 15-45 mN range and with long mission lifetimes, could also take advantage of the high fuel efficiency of a small HET to perform station acquisition and keeping, repositioning, end-of-life disposal, and potentially hybrid transfers from GTO to GEO.This paper presents a comprehensive overview of the analyses of EO and telecommunications mission scenarios based on the use of a low power/mass efficient HET system concept, which has been identified as a promising technology for future applications in these domains.