一种高幅值稳定性的微机械陀螺闭环驱动电路

A Closed-Loop Drive Circuit for Microgyroscopes with High Amplitude Stability

优化设计了一种闭环自激驱动电路,有效提高了微机械陀螺的驱动闭环控制精度。根据自激振荡振幅稳定性理论,对相角和增益解耦的闭环驱动系统幅值控制环路进行了分析,计算得到系统环路增益,推导出系统幅值达到最佳状态的环路参数,优化后陀螺的驱动力仅受控于一个可调变量。实验结果显示,改进后的自激振荡波形的均方差为0.0033V,频率均方差为0.793Hz,输出的幅值和频率的稳定性都得到了较大改善。对幅值控制环路的改进简化了电路调试,有效提高了陀螺系统的测量精度。

A common closed-loop driving scheme was improved to enhance the control precision of microgyroscope.Based on the theory of self-oscillation,the loop gain was calculated in a closed-loop driving system in which the phase angle and gain are decoupled.Furthermore the circuit parameters were optimized through the comparisons of the amplitude-frequency characteristics in different situations.After the optimization,the driving forces were able to be controlled by only one variable,which made the circuit debugging much more easier.Experimental results showed that the standard deviation of the amplitude and frequency were improved from 1.029 V and 0.014 6 Hz to 0.793 V and 0.003 3 Hz,respectively.It proved that the presented circuit scheme could improve the stability of drive frequency and the amplitude effectively.