基于温湿度补偿的扬尘监测装置设计与试验

Design and experiment of a dust monitoring device based on temperature and humidity compensation

针对农田扬尘研究过程中现有扬尘监测装置易受环境温湿度影响,发生零点漂移,导致测量误差大的问题,该研究设计了一种基于温湿度补偿的扬尘监测装置,该装置包括温湿度传感器、质量传感器、数据采集系统等,可实现农田扬尘在线实时监测。通过温湿度与零点漂移相关性试验对采集的4个扬尘监测装置零点漂移与温湿度数据分析,温湿度与扬尘监测装置零点漂移具有显著相关性(皮尔逊系数的绝对值|p|>0.5),且绝对湿度与零点漂移的相关性表现较相对湿度更加稳定,提出了绝对湿度与扬尘监测装置零点漂移的线性函数,函数的湿度系数与温度呈正相关。温度从40℃升至60℃,通过温度与扬尘监测装置输出信号单因素试验表明,零点漂移量是灵敏度变化量的65.7倍,零点漂移是影响扬尘监测装置测量精度的关键因素。建立了基于温湿度的BP网络扬尘监测装置零点漂移补偿模型,试验表明,此模型较基于温湿度的二阶多项式补偿模型数据波动幅度降低了8.8%,较基于温度的BP网络补偿模型降低了60.3%。对本文基于温湿度补偿的扬尘监测装置进行田间测量试验,结果表明,本文监测装置较无补偿扬尘监测装置的最终测量误差降低了57.5%,测量结果波动幅度降低了34.2%,有效降低了扬尘监测装置的测量误差。研究结果可为农田扬尘在线实时监测研究提供技术支撑。

Aiming at the problem that the dust mass measurement of the existing dust monitoring devices in the process of farmland dust monitoring was susceptible to the influence of ambient temperature and humidity,resulting in zero drift and a large measurement error,this study designed a dust monitoring device based on temperature and humidity compensation.The device included temperature and humidity sensors,mass sensor,data acquisition system,etc.,which could realize crossregional,remote,real-time online measurement of dust mass.The zero drift and temperature and humidity data of the four dust monitoring devices collected by the temperature and humidity correlation test showed that the temperature and humidity had a significant correlation with the zero drift of the dust monitoring device(the mean values of|p|were 0.59 and 0.62,respectively),and the correlation between zero drift of the dust monitoring device and absolute humidity was more stable than relative humidity performance,a linear expression of absolute humidity and zero drift of the dust monitoring device was provided,the humidity coefficient of the expression was positively correlated with temperature.When the temperature changed from 40℃to 60℃,the single-factor test of the temperature and the output signal of dust monitoring device showed that the zero drift was 65.7 times that of the sensitivity change,zero drift was a key factor affecting the measurement accuracy of dust monitoring device.A compensation model of the zero-point drift dust monitoring device of BP network based on temperature and humidity was established,the experimental results showed that the data fluctuation range of the proposed model was 8.8%lower than that of the basing on temperature-humidity second-order polynomial compensation model,and 60.3%lower than that of the basing on temperature compensation model of BP network.A field measurement experiment was conducted for the dust monitoring device based on temperature and humidity compensation of this paper.The results showed the device in this paper reduces the final measurement error by 57.5%and the fluctuation of measurement results by 34.2%compared to the uncompensated device,effectively reduced the measurement error of dust mass.The research results could provide technical support for the research on online real-time monitoring of farmland dust.