考虑地磁场空间梯度的飞行器磁干扰建模与求解方法

Modeling of aircraft magnetic interference due to geomagnetic gradient and its solution

首先,在研究飞行器背景磁干扰模型与小信号模型的基础上,分析了地磁梯度沿纬度与高度的变化规律,分析可知由于飞行器的机动,地磁梯度会对测量结果造成影响;然后,考虑地磁梯度因素,对原有小信号模型求解方法进行了改进:飞行器在四个航向上做小角度的机动飞行,将地磁场沿纬度与高度的梯度作为未知量,与飞行器磁干扰模型中的剩磁参数、感磁参数和涡磁参数一起求解;最后,利用实测试验数据进行了验证,结果表明:考虑地磁梯度的影响与不考虑地磁梯度的影响相比,求解的模型参数可以在细节上进一步提高飞行器背景磁干扰的补偿效果。

Firstly, based on the aircraft magnetic field model and the small signal model, this paper makes an analysis of the changing law of the geomagnetic gradient along the latitude and altitude. Thus, it is known that the gradient has influence on the measuring result. Then, the small signal model is improved with the geomagnetic gradient taken into consideration. The unknown latitude gra- dient and altitude gradient can be solved with permanent, induced and eddy-current parameters at the same time by making the aircraft do small angle maneuver in four courses. Finally, the new model is verified by experimental data. The result shows that the solved parameters, in view of the influence of geomagnetic gradient, can further improve the compensation effect in detail.