恒温差工作方式热式流量传感器的研究

分析了热式气体流量传感器的测量原理,根据热耗散理论,推导出了铂电阻传感探头加热电流与气体流量之间的函数关系,研究了基于恒温差工作方式传感器的测量电桥、信号调整和电流调节驱动电路的工作原理,设计了基于三极管基极-集电极的传感器电流调节电路和串并联式温度补偿电路,通过对电路的分析和试验,证明了该电路工作状态稳定,温度补偿效果良好,测试结果具有较好的一致性。

Research of Thermal Type Flow Sensor Based on the Constant Temperature Difference Method

This paper analyzed the measuring principle of the thermal flow sensor,deduced the function between the heating current of the platinum resistance sensing probe and the gas flow under the theory of heat dissipation,researched the working principle of measuring bridge,signal adjustment and current drive of the sensor,designed the current regulation circuit based on the transistor base-collector pole and sensor temperature compensation series-parallel circuit.The following research and experiments proved that the state of ciruit is steady,the compensation of temperature is good and the measurement is consistent.