微机械热对流加速度传感器的频响特性及补偿

Frequency Response Characteristics and Compensation Technique for the Micromachined Thermal Convective Accelerometer

在分析微机械热对流加速度传感器的工作原理及其有限元仿真的基础上,对传感器的瞬态响应进行了分析,建立了描述热对流加速度传感器频率响应特性的半定量的理论模型。结合有限元仿真结果,模型预测的热对流加速度传感器的频响与实际的传感器的频响较好地吻合。设计了传感器频率补偿电路,讨论了电路参数优化的途径,通过电路仿真方法得到优化的电路参数,仿真得到的补偿之后-3 dB带宽为112.5 Hz,构筑了传感器频率补偿电路并对补偿效果进行测试。结果表明:补偿之前-3 dB带宽为22.6 Hz,补偿之后实测-3 dB带宽拓展为106.0 Hz,与仿真结果基本吻合,成功将传感器频响扩展到100 Hz以上,满足应用的需要。

Based on the working principle analysis and finite element simulation of the micromachined convective accelerometer, the transient response process of the accelerometer was analyzed, and the semi-qualitative phenomenological model for the frequency response of the micromachined convective accelerometer was established. Combined with the result of the finite element simula- tion, the frequency response of the micromachined convective accelerometer calculated with the model is good agreement with the actual result. The frequency compensation circuit was de- signed, and the optimization method of the circuit parameters was discussed. The optimized pa- rameters were achieved through the circuit simulation. The simulated - 3 dB bandwidth is 112.5 Hz after the frequency compensation. The frequency compensation circuit of the accele- rometer was set up and the compensation result was measured. The result shows that the - 3 dB bandwidth of the accelerometer is 22.6 Hz before compensation and, the - 3 dB bandwidth is ex- tended to 106.0 Hz after compensation, which is good agreement with the simulation result, and successfully extend the frequency response of the accelerometer to exceed 100 Hz. This is satis- fied with the application requirement.