双H型石英音叉陀螺驱动信号频率跟踪算法的研究

为提高双H型石英音叉陀螺驱动信号的稳定性,基于DSP设计了一种数字化闭环控制电路,依据双H型石英音叉陀螺在串联谐振频率点处工作时驱动叉指振动的幅度随频率变化的影响最小,通过相位控制实现了驱动信号频率的跟踪,并利用希尔伯特变换产生了一对正交的参考信号用作相位检测.实验结果表明,双H型石英音叉陀螺工作稳定后,驱动信号频率跟踪算法的相位标准差为4mrad,精度达到0.003 4Hz.

Study on Frequency Tracking Algorithm of Drive Signal of Double H Quartz Tuning Fork Gyroscope

A digital closed-loop drive control circuit was designed based on digital signal processing(DSP) to improve the stability of the drive signal of double H quartz tuning fork gyroscope, and the frequency tracking algorithm of drive signal was proposed. Considering that the vibration amplitude of the drive tuning fork had a minimal impact with the frequency change, a phase control loop was used to track drive mode resonant frequency, and a pair of quadrature reference signal generated from Hilbert transformer were used to detect phase. Experiments have shown that the phase standard deviation of proposed frequency tracking algorithm is 4 mrad and the frequency tracking accuracy is up to 0.003 4 Hz when the double H quartz tuning fork gyroscope is in stable operation.