The principle of the resonant accelerometer based on electrostatic stiffness was introduced,and its dynamic model was built. According to the requirement of closed-loop control,control equations based on self-oscillation technology was also built for the system. With the help of the averaging method, the system stability was analyzed and the equilibrium for the vibration amplitude was achieved. The influence for vibration amplitude and excited frequency by system phase error was analyzed. Finally a resonant micro accelerometer is fabricated with bulk-silicon dissolved processes and vacuum packaged. Closed-loop experiment show the sensitivity of 18 Hz/g when sensing voltage is 1 V; sensitivity is 58 Hz/g when sensing voltage is 5 V. The maximal error for closed-loop resonance frequency during 10 minutes is 0.2 Hz and the resolution is about 3. 5 mg.%为了研制谐振微机械加速度计,文中介绍了静电刚度的谐振式微加速度计的工作原理,并根据闭环控制要求,建立了基于自激原理的系统分析方程,利用平均周期法分析了系统稳定性和振动幅度稳态平衡点.理论分析确定了系统起振条件和相位偏差对闭环振幅和频率的影响.对基于体硅溶片制造和真空封装的谐振微加速度计,自激闭环测试结果表明检测电压1V时,灵敏度为18 Hz/g；检测电压5V时,灵敏度为58 Hz/g,10 min内闭环谐振频率最大漂移0.2 Hz,可分辨加速度约3.5mg.
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