Rearch On Tea Sorting Product Line Modeling And Human Simulated Intelligent Control System

To turn fresh tea leaves to commodity, preliminary processing and sorting processing are needed. The main purpose of sorting is dividing tea leaves in to several classes that can be packed as uniform commodity tea acorrding to size and thickness of leaves. The different proportions of diverse leaf sizes make the tea flow amounts in different product line branches vary and may fluctuate over time, resulting in the reduce of screening effect and sometimes even block of product line. Therefore, the study of flow model in the production line and construction of flow control system of production line have great significance. The following work has finished in this paper:(1) Screen processes in plane-round shifting machine is analysed. By considering the motion path of the single-particle tea on the screen and probability of tea-leaves going through the screen mesh, tea flow model of plane-round shifting machine that can evaluate the screen effect in case of different tea flow amount and speed of machine is established in Simulink. The simulation result shows screen efficiency varies with running rate and feeding amount of the machine. If screen rate is kept about 230 r/min and feed amount is restricted between 300 and 600 kg/h, screen efficiency can be kept above 85%.(2) Tea flow model of vibrating-shifting machine has been developed in similar way as plane-round shifting machine. Using this model to simulate the screen process, result shows the speed of Vibrating-shifting machine should be adjusted to fit for the fluctuant flow and flow kept in range from 200 to 320 r/min so that screen efficiency can reach above 88%.(3) Construct a flow model of electromagnetic vibration feeder. By connect all models of main product units, a tea sorting product line model is developed. Simulation of the product line flow model verifies the phenomenon of uneven flow among branches of line. To solve this problem, a human simulated intelligent control system combined with Smith predictive compensator is presented. Compared with other traditional control methods, it can effectively eliminate the influence of large delay and improve flow stability of tea flow amount in the product line.