A two-stage extended kalman filter method for fault estimation of satellite attitude control systems

摘要

This paper presents a two-stage extended Kalman filter (TSEKF) method for actuator and sensor fault estimation problem of satellite attitude control systems. A nonlinear system model with unknown faults is established based on the separate-bias principle. Three kinds of models, namely, ACSs System model without faults, ACSs System model with actuator faults, and ACSs System model with sensor faults are established. A TSEKF strategy for state/fault estimation of nonlinear system is investigated, which are applied to these three models to estimate the system states and faults. The simulation results indicate that the amplitude of additive faults of actuator and sensor can be estimated directly. Moreover, the control effectiveness factors representing the multiplicative faults of actuator can also be estimated. Finally, by using the telemetry data of the on-orbit satellite "TS-1" of Harbin Institute of Technology as the measurement vector, the simulation results show that the proposed TSEKF strategy can be applied directly in engineering to reconstruct the actuator and sensor faults. (C) 2016 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.