电容式谷物水分传感器探头设计与试验

doi:10.13733/j.jcam.issn.2095-5553.2024.09.030

摘要/Abstract

摘要：

针对谷物水分传感器安装困难的问题，基于边缘电容效应设计一种同心圆平面电容式水分传感器探头。通过建立仿真模型，分析可行性，并通过试验研究探头结构变化对探头测量灵敏度和测量范围的影响，最终确定探头尺寸结果的最优组合。当电极的极间距与宽度的比值为 5、驱动电极的数量为 1时，传感器探头的灵敏性和测量范围最优。以小麦为研究对象，试验表明小麦含水率与输出电容值之间存在二次线性回归，并研究温度对输出电容的影响，建立水分检测模型，在温度为-5 ℃~40 ℃、含水率为 10%~30%内，相关系数 R2为 0. 997，均方根误差 RMSE为 0. 359。所设计的传感器探头可以满足不同时期小麦含水率测量精度需求，为小麦水分检测提供一种新的传感器探头形式及设计方法。

关键词: 平面电容, 水分传感器, 探头, 电容传感器, 介电特性

Abstract:

Aiming at the problem of difficult installation of grain moisture sensor，a concentric circular planar capacitive moisture sensor probe was designed based on the edge capacitance effect. The feasibility was analyzed by establishing a simulation model，and the influence of probe structure changes on the measurement sensitivity and measurement range of the probe was analyzed by experiments，and the optimal combination of probe size results was finally determined. The sensitivity and measurement range of the sensor probe were optimal when the ratio of inter.electrode moment to width was 5 and the number of driving electrodes was 1. The experiments with wheat as the research object showed that there was a quadratic linear regression between wheat moisture content and output capacitance value，and the effect of temperature on output capacitance was investigated，and a wheat moisture prediction model was established with correlation coefficient R2 of 0. 997 and root mean square error RMSE of 0. 359 in the range of -5 °C-40 °C and moisture content of 10%-30%. The designed sensor probe can meet the requirements of moisture content measurement accuracy of wheat in different periods，and provide a new sensor probe form and design method for wheat moisture detection.

Key words: planar capacitance, moisture sensor, probe, capacitance sensor, dielectric property ,

中图分类号:

孙颖 , 赵丽清 , 殷元元 , 张心培 , 徐鑫 , 马坊岩 . 电容式谷物水分传感器探头设计与试验[J]. 中国农机化学报, 2024, 45(9): 196-201.

Sun Ying, Zhao Liqing, Yin Yuanyuan, Zhang Xinpei, Xu Xin, Ma Fangyan. Design and test of capacitive grain moisture sensor probe[J]. Journal of Chinese Agricultural Mechanization, 2024, 45(9): 196-201.

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