硅微陀螺仪正交误差校正系统的分析与设计

Analysis and design of quadrature error correction system for silicon micro-gyroscopes

由于加工误差的存在,硅微陀螺仪驱动和检测模态之间不可避免会产生正交耦合误差,对性能造成了一定影响。为了提高硅微陀螺仪性能,提出了正交误差校正的控制方案。首先,分析了硅微陀螺仪正交误差的产生原因,指出了对正交误差校正的重要性;其次,阐述了在结构上增加电极抑制正交误差的原理;然后,设计了正交误差信号提取电路和正交误差反馈控制校正系统,分析了闭环控制系统性能;最后,设计了实验验证方案。结果表明,零偏电压从校正前的5.14 mV减小到校正后的1.43mV,零偏稳定性从校正前的18.22(o)/h减小到校正后的15.45(o)/h。因此,该正交误差校正方案能够有效地消除零偏信号中解调残余正交分量,从而提高硅微陀螺仪性能。

The existence of processing errors will inevitably produce quadrature coupling errors between drive and sense modes of silicon micro-gyroscope. This paper put forward a quadrature error correction control program. First, the cause of quadrature error of silicon micro-gyroscope is analyzed, and the importance of quadrature error correction is pointed out. Second, the principle of adding electrodes in the structure for suppressing the quadrature error is described. Then, the quadrature error signal extraction circuit and the quadrature error correction system with feedback control are designed, and the performance of closed loop control system is analyzed. Finally, an experimental verification scheme is designed. The experiment results demonstrate that, after correction, the zero bias voltage decreases from 5.14 mV to 1.43 mV, and the zero bias stability reduces from 18.22 (°)/h to 15.45 (°)/h, showing that the quadrature error correction scheme can effectively eliminate the demodulation residual quadrature error in zero bias signals and improve the performance of silicon micro-gyroscope.