Development Of Yellow Tea Yellowing Equipment And Study On Temperature And Humidity Control Method

Yellow tea is one of the six kinds of tea in China,and its yield and output value have increased greatly in recent years.Yellowing is one of the important processes in the production and processing of yellow tea,which has a direct impact on the quality of yellow tea.Therefore,the research and development of special equipment for yellowing of yellow tea has become the key to improve the yield and quality of yellow tea.This paper designs and verifies the overall development plan of the chlorination equipment,and researches some key technologies.The specific work is as follows:(1)The structure of chlorination equipment was designed.The yellowing process of yellow tea was analyzed,and the functional requirements of yellowing equipment were determined to control the temperature and humidity as well as the time of yellowing.According to the functional requirements,the specific implementation scheme of heating and humidification of equipment was designed.Choose flip plate dryer as yellowing box,and integrate electric furnace as heating device,steam generator as humidification device and centrifugal fan as ventilation device to form the main structure of yellowing equipment,complete the integrated construction of mechanical structure of yellowing equipment.(2)The control system of chlorination equipment is designed.PLC as the control core,combined with temperature and humidity sensor,inverter and other control components and peripheral circuit design of the control circuit,to achieve the electrical control of the yellowing equipment.(3)The control software and temperature and humidity algorithm based on fuzzy control are designed.Based on the control circuit to complete the PLC control program;Lab VIEW software was used to make human-computer interaction interface,complete the equipment parameter setting and temperature and humidity data records and other functions,to achieve the automatic control of the equipment;The temperature and humidity algorithm based on fuzzy control is designed,the system variables,variable domain,fuzzy rules and membership function in the temperature and humidity fuzzy control system are designed in detail,and the temperature and humidity fuzzy control query table is obtained.After operation test verification,the yellowing equipment designed in this paper can achieve effective control of temperature and humidity,temperature error is controlled within ±1℃,humidity error is controlled within ±3%RH,the equipment can run steadily for a long time,meet the design indicators and yellowing process requirements.The research of special equipment for yellow tea yellowing and temperature and humidity control system provides a new technical path and thought for the development of tea processing machinery,and provides a solid foundation for the standardization of yellow tea processing and further optimization of equipment.