阐述了新研制的烘干机温度PID控制系统结构原理。用该系统进行大红袍精制烘焙应用试验,研究表明,设定温度为180℃,PID控制系统平均热风温度为181.9℃,人工控制平均热风温度为188.9℃,PID控制烘焙温度比人工控制更加稳定,节煤率为22.97%~26.83%;PID控制与人工控制烘焙的两种等级大红袍茶多酚含量均达到显著水平,一级大红袍的氨基酸含量达到极显著水平,二级大红袍的氨基酸和可溶性糖含量达到显著水平;PID控制烘干的茶叶感官品质优于人工控制。

This paper described the structure and principle of the temperature PID control system of dryer, and Dahongpao refined baked application experiment was carried out. The results showed that: When the set temperature is 180℃, the average air temperature is controlled at 181.9℃ by the PID system, and the average air temperature controlled by manual is 188.9℃, the baking temperature controlled by PID control system is more stable than manual control, and coal saving rate is about 22.97%-26.83%. In the two different quality levels of Dahongpao, tea polyphenols in the tea drying controlled by the PID and the manual are reached significant level, the amino acid of first-class Dahongpao reached very significant level, the amino acid and soluble sugar of secondary class Dahongpao reached significant level. The average tea quality scores under temperature PID control is higher than that of manual control.