热泵干燥系统温湿度控制实验研究

Experimental Research on the Temperature and Relative Humidity Control in Heat Pump Drying System

针对闭式热泵干燥系统非线性,强耦合等特点,将干燥循环分成升温过程和降温过程,并针对不同过程设计了相应的温度模糊控制策略。干燥过程温度、湿度是影响干燥物料品质的关键因素,为了提高干燥物料品质在温度控制的基础上设计了湿度模糊控制方案并给出了温湿度解耦策略。对温湿度的模糊控制效果进行了实验检测。系统运行结果表明:温湿度控制效果显著,温度的偏差控制在±0.8℃,湿度的偏差控制在±3%RH。

The drying process was divided into two processes： heating process and cooling process because of the non-linear and strong coupling characteristics of heat pump drying system. Therefore, the temperature control strategy should be divided into the heating and cooling fuzzy controls. Both of the temperature and relative humidity of the drying air are key factors affecting the quality of dryed materials. In order to improve the quality of dryed materials, a humidity fuzzy control strategy was promoted based on the control of temperature. From the results of experiment, the control strategy gives high temperature and relative humidity precision： the deviation of of temperature control is ±0.8℃ and the relative humidity is ±3%.