| At present, the domestic fixing equipment is mainly semi-manual-semi-automatic, which cannot fully meet the technological requirements of the tea fixation. In the fixing process, appropriate technological parameters are difficult to control, and the fixing operation doesn’t work stably. In hence, the quality of tea is limited. The Fuzzy PID control has the advantages of flexibility, wide versatility and high accuration. It could realize the accurate control for controlled objects, and it has been widely using in the control processing of the agricultural products. Online moisture detecting technology could enable the real-time monitoring of the product moisture during the process and feedback the information of the product. It plays an important role in adjusting the process parameters online.This research focused on the automatic control system for green tea fixation, which consists of fuzzy PID control technology and online moisture detecting technology as the core issues. It concentrated on the stability of the automatic control system for green tea fixation, providing significant references for the automated production of high-quality green tea.This paper not only describes the overall structure of the automatic control system for green tea fixation, but also discusses the overall automation solution of this system. The analysis of the control theory and method theoretically proved the reasonability of the stability in control processing. With Simulink simulation toolkit, the simulation and the analysis of the fuzzy PID control effect for water content of the fixed leaves verified the feasibility of the control.The IR3000 Configuration software is used to calibrate the parameters of near-infrared moisture meter, for detecting the fresh leaves under different conditions. The result of the experiments shows that the sensitivity and stability of near-infrared moisture meter is qualified for the moisture content detection. In this study, the working mechanism of the automatic control system for tea fixation was introduced. Based on the analyzing of the requirements for the hardware of the automatic control system, the control loop and driver were implemented. And the spring-, summer-and autumn-collected teas are tested on the green tea fixation automatic control system. The moisture content control analysis, sensory evaluation and the quality components were detected. The results show that the system design is reasonable and the machine works properly. Under different modes, the system could work automatically, stably, and well. |
PDF Full Text Request