低功耗低温漂数字式电容角位移传感器

A Low-Power Consumption, Lower Temperature Drift,Digital Capacitive Angular Displacement Transducer

旨在研制一种测量范围为180°的新型数字式电容角位移传感器,并着重解决传感器的功耗及温漂问题．以比例式测量原理为基础,给出优化的激励模式及实施电路;根据转动极板为金属材质且电气悬空设计时计算角的象限判断标准和计算公式进行信号处理．以超低功耗单片机作为信息处理的核心单元,既保证了运算速度,又可以实现通讯,同时有效地降低了系统功耗,实现了4～20 mA工业标准信号的远传,甚至电池供电．误差实验表明, 在-10℃～55℃范围内,传感器温漂最大值小于0．113％／10℃．

This paper aims to develop a digital capacitive angular displacement transducer with the 180° measurement range and settle the power consumption and temperature drift of the transducer. An optimal excitation pattern and its implemental circuit are given based on ratiometric measurement principle. The signal is processed according to the criterion of judging the quadrant and formula of angle when the rotor is overhung and made of metal. The core unit of the information processing is a ultralow-power consumption MCU, which can ensure the computing speed, realize communication, and lower the power consumption of system effectively. The transducer presented here can reach the 4 -20 mA industrial standard signal output and even can be supplied by battery. Error experiments indicate that the maximal temperature drift of the transducer is lower than 0. 113%/10 ℃ when the temperature is from - 10℃ to 55 ℃.