关键词: 冷气推进系统；姿态控制；泄漏；估计；预测；遥测

Abstract: With respect to long-term management of satellites on orbit in TTC (Tracking， Telemetry and Command)， cold gas propellant leakage is a key performance parameter for LEO (Low Earth Orbit) satellite propulsion system. Based on the orbital dynamics data， details on solar incidence shift and semi major axis degradation are discussed. After analyzing pressure and temperature parameters from satellite history telemetry data， an estimation has presented to model propellant leakage with gaseous equation. This estimation has calculation error analysis based on formula derivation， and satellite attitude change caused by propellant leakage has been considered， too. In the following stage， a prediction has made to calculate the remaining propellant to work for attitude control. Validated by cold gas pressure and temperature data from satellite telemetry， the result has illustrated that cold gas propellant of nitrogen has a leakage between 150Pa·cm3·s-1 and 450Pa·cm3·s-1 from the original pressure about 13MPa in the early 5 years， and has a gradual convergence of 275Pa·cm3·s-1 that is approximately about 3.4μg/s for nitrogen gas in subsequent years. At the same time， the result has implied that the remaining propellant mass is more than 85% of the original mass in the early 10 years and will be more than 60% of that after the following 20 years. By calculating precision of satellite attitude control system data such as attitude angle， magnetic torque current and momentum wheel revolution， cold gas leakage has nearly zero effect to satellite attitude. Finally， estimation and prediction result is applicable to telemetry diagnosis assistant for long-term management of satellite on orbit， and to evaluation of device SOH (State of Health) for longevity satellite.

Key words: Cold gas propulsion system；Attitude control；Leakage；Estimation；Prediction；Telemetry