光纤陀螺在直流及交变磁场中的磁敏感性研究

介绍了光纤陀螺的磁敏感性机理并进行了实验研究。利用亥姆霍兹线圈装置和光纤陀螺测试平台,研究了光纤陀螺在直流磁场中的磁敏感性,得到光纤陀螺数据输出与磁感应强度基本呈线性关系,以及轴向磁场和径向磁场影响系数的大小和光纤陀螺磁敏感轴的方向。主要针对50Hz的交流磁场研究交流磁场对光纤陀螺零偏和零漂的影响及其交流磁敏感性,得到交流磁场对零偏的影响可以忽略,但磁感应强度与陀螺零漂值的大小基本呈线性关系。研究了不同频率交流磁场对光纤陀螺输出的影响,说明了光纤陀螺数据输出主要与瞬态的磁感应强度成正比,不同频率交流磁场对光纤陀螺零漂值的影响不同,存在一个频率(或频率范围)对光纤陀螺零漂的影响较大,其频率范围与光纤陀螺输出带宽有关。

Magnetic Sensitivity Studies of Fiber Optic Gyroscope in Direct Current and Alternating Current Magnetic Fields

The mechanism of the magnetic sensitivity of fiber optic gyroscope (FOG) is introduced and experimental study is done. The Helmholtz coils equipment and FOG test platform is utilized, the magnetic sensitivity of FOG in direct current (DC) magnetic field is studied, and the linear relation of FOG data output and the magnetic flux density is found. Axial magnetic field and radial magnetic field influence coefficients and the orientation of the magnetic sensitivity axis of FOG are also found. Then the influence on FOG bias and bias stability and the alternating current (AC) magnetic field sensitivity in 50 Hz AC magnetic field are mainly analyzed, finding that the influence of AC magnetic field on the bias can be neglected, but the magnetic flux density and the size of FOG bias stability are almost linear relation. Finally the influence of different frequency AC magnetic fields on the FOG data output is studied, indicating that the data output of FOG is mainly proportional to the transient magnetic flux density, different frequency AC magnetic fields have different influences on the bias of FOG. There is a frequency (or frequency range) with much stronger influence on the bias of FOG, which is related to FOG output bandwidth.