地磁测量卫星的矢量磁场在轨标定算法仿真

The precision of geomagnetic survey satellites represented by SWARM is better than 0.5 nT for detection of the Earth’s magnetic field after calibration. The satellites obtain the geomagnetic information of inertial space attitude in measurement direction through the vector fluxgate magnetometer, scalar magnetometer and high-precision star tracker installed on the extension boom. The high-precision scalar magnetometer is mainly used to calibrate the fluxgate vector magnetometer. Calibration methods of in-orbit measurement error of vector magnetometer are proposed for geomagnetic survey satellite. Considering the non-orthogonal angles, scale factors and deviations of vector magnetometer, the linear output model of magnetic field vector is established. The linear correction algorithm based on small approximation and nonlinear correction algorithm based on parameters identification update are designed respectively combined with the measurement values of scalar magnetometer. The calibration accuracy of algorithms is verified, and the robustness of the algorithms is improved by Tukey weight function. Simulation results show that the correction results are similar, the triaxial errors of magnetic field can be corrected to less than 0.5 nT, and the algorithms still have a good correction effect when there is an outlier in scalar measurements.