一种新型硅微陀螺仪闭环驱动方案的研究

研究了一种新的硅微陀螺仪闭环驱动方案,对推挽驱动方式的性能进行了分析,结果表明驱动力矩的频段与噪声信号频段是分离的,因此噪声信号不会影响到驱动效果。在此基础上,利用锁相技术满足正弦自激振荡的相角和增益条件,建立环路的自激振荡,实现了闭环控制。同时在闭环回路中利用正弦自激振荡的相角条件和锁相环的鉴相特性,消除了驱动信号对敏感信号的同频干扰,并抑制了环路中的噪声干扰,明显提高闭环性能。试验结果显示在1小时内交流信号频率和幅度的标准方差分别为0.132 H z和0.258 mV,实现了驱动稳幅稳频的目的,从而使陀螺仪精度和可靠性得到了显著提高。

A New Closed-loop Driving Circuit of Silicon Micromachined Vibratory Gyroscope

This paper describes a new closedloop drive scheme for Silicon Micromachined Vibratory Gyroscope(SMVG).The scheme adopts the push-pull drive.The paper analyses the performance of the drive.The results show that the frequencies between driving moment and noise signal are separated.On the basis of that,the model of closed-loop control is set up with the Phase Lock Loop(PLL).The circuit makes use of the phase conditions of the sinusoidal self-drive-oscillation and the peculiarity of phase discrimination of Phase Lock Loop.The analytic results of the performance of closed-loop control show coupling of the drive signal to sense signal that is used to closed-loop control is eliminated,and the noise signal in the loop is eliminated.Finally,the experiments show that the standard deviation of drive frequency and the amplitude are 0.132 Hz and 0.258 mV respectively,which makes the precision and reliability of gyroscope greatly improved.