基于介电特性的三七粉含水率检测与建模

Predicating and Modeling of Moisture Content of Panax Notoginseng Powder Based on Dielectric Properties

为了探索三七粉介电特性与含水率之间的关系,利用LCR测试仪研究频率信号（0.1-1 000 k Hz）,温度（15-55℃）和含水率（9.8%-17.8%）对三七粉介电特性的影响.结果表明,在0.1-10 k Hz频段内,相对介电常数ε＇和介质损耗因数ε″变化趋势明显;ε＇和ε″随着频率的增大而减小,随着温度和含水率的增大而增大.随后在1 k Hz和10 k Hz下建立了基于介电特性（ε＇和ε″）和温度T预测三七粉含水率（W%）的模型,在1 k Hz下,预测模型的R2=0.977 3.最后,制作了50个样本,对模型进行验证,将试验值与模型计算值进行比较,发现其误差范围在±3.9%,说明所建立的模型是可行的.该研究结果对开发三七粉含水率检测仪具有一定的指导意义.

Panax notoginseng powder was used to study the influence of frequency（ 0. 1 - 1000 k Hz）,temperature（ 15 - 55 ℃） and moisture content（ 9. 8% - 17. 8%） on the dielectric properties in the LCR measuring meter and after that we will analyze the reason for dielectric constant and loss factor changed with these factors. The results showed that when the frequency is between 0. 1 and 10 k Hz,the influence of dielectric constant and loss factor is more distinct and the two parameters increased as moisture content and temperature increasing,decreased with frequency increasing. The prediction equation of the moisture content was established based on relative dielectric constant,loss factor and temperature for the sample under the 1 k Hz and 10 k Hz. And the most suitable coefficients of determination is 0. 9773 at 1 k Hz. 50 samples were used to compare the measured values and calculated values of moisture content,it showed that the errors of predicated moisture contents of Panax notoginseng powder based on dielectric properties at 1 k Hz is within ± 3. 9%. The prediction equation can be used to describe the moisture content of the Panax notoginseng powder based on dielectric constant and temperature. The study is helpful to develop the Panax notoginseng powder＇s moisture detector based on dielectric properties.