基于Simulink的数字闭环光纤陀螺频率响应特性研究

Research on frequency response characteristics of digital closed⁃loop fiber optic gyroscope based on Simulink

为了深入研究闭环光纤陀螺的频率响应特性,基于Simulink搭建了数字闭环光纤陀螺仿真模型,分析了四态方波调制下影响闭环光纤陀螺的频率特性的主要因素。结果表明,数字闭环光纤陀螺的稳定性条件为数字开环增益小于0.618。当数字开环增益小于0.16时,控制系统不存在超调。数字闭环光纤陀螺的频率带宽与数字开环增益和陀螺本征频率成正比,通过减小光纤长度及适当提高控制增益可以提高数字闭环光纤陀螺的频率带宽。

In order to study the frequency response characteristics of the closed⁃loop fiber optic gyroscope in depth,a digital closed⁃loop fiber optic gyroscope simulation model was built based on Simulink,and the main factors affecting the frequency characteristics of the closed⁃loop fiber optic gyroscope under four⁃state square wave modulation were analyzed.The results show that the stability condition of the digital closed⁃loop fiber optic gyroscope is that the digital open⁃loop gain is less than 0.618.When the digital open loop gain is less than 0.16,there is no overshoot in the control system.The frequency bandwidth of the digital closed⁃loop fiber optic gyroscope is proportional to the digital open⁃loop gain and the intrinsic frequency of the gyroscope.The frequency bandwidth of digital closed loop FOG can be improved by decreasing fiber length and increasing control gain appropriately.