With the development of high-precision inertial navigation systems, the deflection of vertical (DOV), gravity disturbance, is still one of the main error sources that restrict navigation accuracy. For the DOV compensation of the Strapdown Inertial Navigation System (SINS) problem, the influences of the calculation degree of the spherical harmonic coefficient and the calculation error of the DOV on the compensation effect were studied. Based on the SINS error model, the error propagation characteristics of the DOV in SINS were analyzed. In addition, the high-precision global gravity field spherical harmonic model EIGEN-6C4 was established and the influence comparative analysis of the calculation degree of the spherical harmonic coefficient on the DOV compensation of SINS in different regions was carried out. Besides, the influence of the calculation error of the DOV on the compensation was emphatically analyzed. Finally, the vehicle experiment verified the feasibility of compensation in SINS based on the gravity field spherical harmonic model. The simulation and experiment results show that it is necessary to consider the influence of the calculation degree and the calculation error of the DOV on the compensation for long-time high-precision SINS with the position accuracy of 0.3 nm/h, while the SINS with general requirements for position accuracy can ignore the impact.

中文翻译：

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惯性导航系统垂直补偿偏差分析

随着高精度惯性导航系统的发展，垂直偏转（DOV），重力干扰仍然是限制导航精度的主要误差源之一。针对捷联惯导系统（SINS）问题的DOV补偿，研究了球谐系数的计算程度和DOV的计算误差对补偿效果的影响。基于SINS误差模型，分析了DOV在SINS中的误差传播特性。另外，建立了高精度全球重力场球谐模型EIGEN-6C4，并对球谐系数的计算程度对不同区域SINS的DOV补偿进行了影响比较分析。除了，着重分析了DOV计算误差对补偿的影响。最后，车辆实验基于重力场球谐模型验证了捷联惯导系统补偿的可行性。仿真和实验结果表明，对于定位精度为0.3 nm / h的长期高精度SINS，DOV的计算程度和计算误差对补偿的影响是必要的，而SINS的定位精度为0.3 nm / h。一般对位置精度的要求可以忽略不计。