摘要
针对电容式加速度传感器的闭环控制需求,设计了 一种电磁反馈系统,以满足用于惯性导航的高精度加速度传感器的需求.该系统保证了加速度传感器具有高机械灵敏度的同时,还能拓宽其量程.建立了电容式微机电系统(MEMS)加速度传感器的闭环控制模型,并对电磁结构进行了有限元分析.仿真结果表明:线圈电流为277.3 μA时,电磁力达到了 1.509 mN.当输入反馈电压为-19.1～19.1 mV时,反馈系统能实现加速度传感器在±5g(g=9.8 m/s2)范围内的闭环控制.计算表明加速度传感器敏感结构的机械噪声为1.22×10-8g/Hz1/2.利用Simulink分析可知,在±5g范围内,电容式MEMS加速度传感器闭环控制系统的反馈电压与输入加速度具有良好的线性关系,其灵敏度为3.8 mV/g.
Abstract
An electromagnetic feedback system was designed for the closed-loop control of capacitive acceleration sensors to meet the needs of high precision acceleration sensors for inertial navigation,which can keep high mechanical sensitivity and im-prove the range of acceleration sensors simultaneously.A closed-loop control model of capacitive micro-electro-mechanical-system acceleration sensors was established and finite element analysis of the electromagnetic structure was performed.The simulation re-sults show that the electromagnetic force has capable of 1.509 mN when the coil current is 277.3 μA.The closed-loop control can be realized by the feedback system within the range of±5g(g=9.8 m/s2)when the input feedback voltage is from-19.1 mV to 19.1 mV.The calculation results show that the mechanical noise of the structure equals to be 1.22×10-8 g/Hz1/2.The feedback voltage of the capacitive MEMS acceleration sensors closed-loop control system with a sensitivity of 3.8 mV/g,which has a good linear relationship with the input acceleration within the range of±5g by the Simulink analysis.
基金项目
山西省基础研究计划面上项目(202103021224206)
国家自然科学基金面上项目(52175524)
山西省"1331工程"重点学科建设项目()
NETL
NSTL
万方数据