基于ARM处理器的双加热湿度传感器设计

摘要

为消除地面气象探测领域中湿度传感器的温漂误差与沾湿误差,设计了一种双加热湿度传感器.利用24位低噪声模数转换器和电容-数字转换器实现温度和湿度的低噪声、高线性度测量,以Optidew Vision冷镜式露点仪作为标定仪器并结合遗传算法拟合修正温漂,使用交替加热的方法抑制沾湿误差.实验结果表明,该传感器的相对湿度测量精度可达±1%,并在6 min内将10%量级的沾湿误差降低至±1%.%In order to compromise the temperature drift error and the water wetting error of the humidity sensors in surface meteorological observation,a heated twin humidity sensor was proposed.Low noise and high linearity measurement of the tempera-ture and humidity was achieved by using a 24-bit analog-digital converter and a capacitance-to-digital converter.An Optidew Vi-sion chilled mirror dew point hygrometer worked as a reference,while a genetic algorithm was constructed to correct the tempera-ture drift.A twin-heating mechanism was employed to refrain the water deposition.Experimental results show that the relative hu-midity can reach ±1%,and that the water wetting error on the order of 10%can be reduced to ±1%in 6 minutes.