锁相环相位误差对半球谐振陀螺零偏影响分析与校准

Analysis and calibration of the effect of phase-locked loop phase error on the bias of hemispherical resonant gyroscope

针对两件套半球谐振陀螺力平衡模式闭环控制系统中的锁相环相位误差问题,开展了锁相环相位误差对陀螺影响分析,并提出了一种锁相误差校准方法。基于带阻尼和弹性耦合的动力学方程,推导了存在锁相误差情况下的各控制力表达式,对谐振频率、标度因数和零偏的影响进行了理论分析和仿真验证。发现锁相误差对谐振频率的影响可以忽略,仅为1.35 ppb/°;对标度因数具有一定影响,锁相误差1°处,为152 ppm/°;而对陀螺零偏影响较大,频差0.001 Hz时,为10.8704°/h/°。提出了一种基于幅度控制量极小值的锁相误差校准方法,实验结果表明,校准后零偏减小了54%,验证了所提方法的有效性。

Aiming at the phase-locked loop phase error problem in the two-piece hemispherical resonant gyro force-rebalanced mode closed-loop control system,the influence of phase locked loop(PLL)phase error on gyroscope is analyzed,and a calibration method for PLL phase locked error is proposed.Based on the dynamic equation with damping and elastic coupling,the expression of each control force in the presence of phase-locking error is deduced.The effects on resonant frequency,scale factor and bias are theoretically analyzed and verified by simulation and experiment.It is found that the influence of phase-locking error on the resonant frequency can be ignored,which is only 1.35 ppb/°.It has a certain influence on the scale factor,which is 152 ppm/°when phase-locking error is 1°.However,it has a great impact on the bias of the gyro,which is 10.8704°/h/°when the frequency split is 0.001 Hz.A calibration method of phase-locking error based on minimum of amplitude control amount is proposed.The experimental results show that the bias is reduced by 54%after calibration,which verifies the effectiveness of the proposed method.