基于偶极子补偿法的硅微机械陀螺仪带宽拓展  

Silicon MEMS gyroscope bandwidth expanding based on bipole compensation technology

作　　者：曹慧亮[1,2] 李宏生[2] 申冲[1] 刘俊[1] 杨波[2] 

机构地区：[1]中北大学电子测试技术重点实验室,太原030051 [2]东南大学仪器科学与工程学院,南京210096

出　　处：《仪器仪表学报》2015年第11期2427-2434,共8页Chinese Journal of Scientific Instrument

基　　金：国家杰出青年科学基金(51225504);国家973计划(2012CB723404);国家自然科学基金委员会和中国工程物理研究院联合基金(U1230114);中北大学基金项目资助

摘　　要：硅微机械陀螺仪的机械灵敏度与驱动和检测模态的谐振频率差Δf成反比,而Δf处的谐振峰是影响陀螺带宽的直接因素,带宽约0.54Δf,因此,带宽和机械灵敏度往往成为两个互为矛盾的指标。基于自动控制原理中介绍的偶极子理论提出了偶极子补偿控制技术,该方法在不影响机械灵敏度的前提下可有效拓展陀螺带宽。首先,对涉及到的双质量硅微机械陀螺仪的结构形式和工作原理进行了介绍,指出陀螺实际工作的检测模态是由检测同相和反相模态叠加而成,设计了陀螺开环检测回路,分析了带宽是由驱动反相和检测反相模态的谐振频率差决定,并结合检测力反馈激励法验证了上述结论;其次,根据偶极子工作原理设计了偶极子补偿控制器的系统传递函数和电路,并对相关内容进行了仿真,验证了电路参数的准确性;最后,基于偶极子补偿控制器建立了硅微机械陀螺仪闭环检测系统,分析了该系统的稳定性,并对该系统的带宽特性进行了仿真和测试,结果显示带宽由原来的13 Hz拓展到了76 Hz,很好地证明了本文提出方法的可行性。此外,鉴于双质量陀螺的实际检测模态,在消除了第一个Δf谐振峰对带宽的影响后,由检测同、反相模态叠加产生的共轭零点引起的幅值谷为带宽进一步提高的限制因素。The mechanical sensitivity of the silicon MEMS gyroscope structure is inversely proportional to the resonance frequency differenceΔf of the driving and sensing modals. The resonance peak atΔf is the direct factor influencing the gyroscope bandwidth,and usually the bandwidth is about 0. 54Δf. So the mechanical sensitivity and bandwidth become two conflict parameters and trade-off should be considered during structure design. This paper proposes a bandwidth expanding method based on the bipole compensation technique in automatic control theory,which can effectively expand the gyroscope bandwidth without influencing the original mechanical sensitivity,and break the Δf resonance peak（ generated by the conjugate poles of the driving and sensing inverse modals） restrict. Firstly,this paper introduces the structure and operation principle of the dual-mass decoupled silicon MEMS gyroscope,and points out that the sensing modal of the gyroscope in real operation is the superposition of the sensing in-phase modal and sensing inverse modal. The gyroscope open-loop sensing circuit is designed; and it is pointed out that the bandwidth is determined by the resonance frequency difference of the driving inverse and sensing the inverse modals. The above conclusion was verified by the sensing feedback force stimulation method（ SFFSM）. Secondly,the transfer function and circuit of the bipole compensation controller were designed based on the bipole operation principle; and related simulations were conducted,which verifies the accuracy of the circuit parameters. Finally,the silicon MEMS gyroscope close-loop detection system was built based on the bipole compensation controller,the stability of the close-loop system was analyzed. The bandwidth characteristic of the close-loop system was simulated and tested with SFFSM. The results show that the bandwidth is expanded from original 13 Hz to 76 Hz,which proves the feasibility of the proposed method. Furthermore,considering the actual sens-ing modal of the dual-mass decoupled

关 键 词：硅微机械陀螺仪 偶极子补偿 带宽拓展 模态叠加 谐振峰 控制器设计 

分 类 号：TH89[机械工程—仪器科学与技术]