光纤陀螺仪双层加热片设计与磁场分析

Design and magnetic field analysis of double-layer heatingplate for fiber optic gyroscope

在复杂电磁环境中,磁场干扰是光纤陀螺仪产生误差的主要原因之一。为了减小光纤陀螺仪台体中加热片产生的磁场对陀螺仪精度的影响,设计了双层加热片结构,并采用有限元方法对单、双层加热片上方光纤环位置处的磁场进行对比分析,根据分析结果计算磁场对光纤陀螺仪精度的影响,结果表明:两种加热片在光纤环位置处磁场均为非均匀磁场,光纤环距离加热片较近处的磁通密度呈现环状分布,距离加热片较远处的磁通密度呈中心强周围弱分布;随着光纤环平面与加热片间的距离增加,光纤环平面上单层加热片的磁通密度最大值约为双层加热片的30至122倍;双层加热片磁场对光纤陀螺仪磁敏感相位误差随磁场方向与光纤环之间的角度呈现倾斜正弦变化;单层和双层加热片在光纤环下表面处产生的磁场磁敏感相位误差分别为1.299×10^(-10)rad和5.572×10^(-12)rad。以上结果证明了双层加热片磁场对光纤陀螺仪的干扰远小于单层加热片,双层加热片产生的电磁干扰更小,更有利于提升光纤陀螺仪的精度。

In a complex electromagnetic environment,magnetic field interference is one of the main reasons forthe error of fiber optic gyroscopes.To reduce the influence of the magnetic field generated by the heating plate in thebody of the fiber optic gyroscope on the accuracy of the gyroscope,a double-layer heating plate structure is designed,and a comparative analysis of the magnetic field at the fiber optic ring position above the single-layer and double-layerheating plates is carried out by using the finite element method,and the influence of the magnetic field on the accuracyof the fiber optic gyroscope is calculated based on the analysis results.The results show that the magnetic field of bothheating plates is non-uniform at the location of the fiber optic ring.The magnetic flux density near the fiber optic ringto the heating plate has a ring-like distribution,while the magnetic flux density away from the heating plate has astrong center and weak center distribution.With the increase in the distance between the fiber ring plane and theheating plate,the maximum magnetic flux density of the single-layer heating plate on the fiber ring plane is about 30to 122 times that of the double-layer heating plate.The magnetic sensitivity phase error of the fiber optic gyroscopevaries sinusoidally with the direction of the magnetic field and the angle between the fiber ring.The phase errors of themagnetic field on the lower surface of the fiber ring are 1.299×10^(−10) rad and 5.572×10^(−12) rad,respectively.The aboveresults prove that the magnetic field of the double-layer heating plate interferes with the fiber-optic gyroscope muchless than that of the single-layer heating plate and that the electromagnetic interference generated by the double-layerheating plate is much smaller,which is more conducive to improving the accuracy of the fiber-optic gyroscope.