MEMS气体流量传感器的简易流量测试装置

为了完成所研制的MEMS气体流量传感器样品的流量测试与标定,设计制作了一种由标准流量发生器和传感器信号读出与数据采集电路组成的简易流量测试装置。标准流量发生器由注射器和可更换的砝码组成,利用不同的砝码配重,在注射器出气口产生合适的恒定气体流速。通过理论分析和Ansys有限元数值仿真,验证了简易标准流量发生器的可行性。传感器信号读出与数据采集电路基于内建多路A/D转换器的单片机实现,具有传感器加热电阻器的恒温控制、流量信号的数字检测和显示的功能。采用该简易流量测试装置对自行研制的MEMS气体流量传感器进行了流量测试与标定,获得了待测器件的标定参数、传感器流量测量的绝对误差和相对误差。

Simplified flow test device for MEMS gas flow sensors

To fulfill flow test and calibration of the developed MEMS gas flow sensor prototypes, a simplified flow test device composed of standard flow generator and a signal read-out and data acquisition circuit is designed and fabricated. The standard flow generator is composed of an injector and a variable weight, with a variable weight, a series of suitable constant gas flow rates can be generated at the injector outlet. Feasibility of the simplified standard flow generator is verified by theoretical analysis and numerical simulation with the Ansys software. The sensor read-out circuit and data acquisition circuit are realized based on microcontroller with multi-channel built-in A/D convertors, which has functions as constant temperature control of sensor heater, digital detection and display of flow signals. Using the simplified flow test device, flow test and calibration on the developed MEMS gas flow sensor prototypes is accomplished. Calibration parameters, absolute error and relative error of flow tests of sensor is obtained.