【作者】 傅杰；

【导师】 赵章风；

【作者基本信息】 浙江工业大学 ， 机械工程， 2017， 硕士

【摘要】 自21世纪以来,我国国民经济快速发展,人民生活水平持续提高。此背景下,人们对茶叶饮料的需求也随之加大、对其品质要求也随之加高。作为世界上最主要的茶叶生产与消费国,其最主要的茶叶消费是绿茶。而茶叶理条作为绿茶初制过程中的一道关键工序,对绿茶的品质形成起着至关重要的作用。针对茶叶理条工艺存在温度控制精度不高、波动大,且过于依赖人工经验,无法根据不同的情况使用最佳工艺参数理条茶叶,导致茶叶出现色泽变黄、变暗或产生焦味等问题,本文基于模糊算法、模糊PID算法,结合MATLAB/SIMULINK仿真技术设计了茶叶理条工艺参数模糊决策控制器与温度模糊PID控制器,进行了计算机仿真。并设计了控制系统软件与硬件,在茶叶理条机上进行了实验。本人所做主要工作和成果如下:(1)分析了茶叶理条工艺及本文所采用的茶叶理条机机械结构特点及其工作原理;根据物料干燥理论确定了茶叶理条过程主要处于恒速干燥阶段;分析了一阶惯性滞后控制系统,温度控制系统的特点与基本控制方法,建立了理条机温度控制系统传递函数。(2)对PID控制算法、模糊算法、模糊PID控制算法进行了理论研究,再此基础上设计了茶叶理条工艺参数模糊决策控制器和基于改进型PID算法的温度控制模糊PID控制器,并利用MATLAB/SIMULINK计算机软件对其进行了控制系统仿真,设计了控制系统硬件与软件。(3)提出了基于嵌入式技术与模糊控制技术的茶叶理条机控制系统设计方案:采用茶叶湿度等级、品种、投叶量作为输入,通过模糊算法决策得到当前茶叶的最佳理条工艺参数;通过模糊PID温度控制算法进一步提高理条机锅槽温度的控制精度,同时减少温度波动;根据温度偏差适量改变锅槽振动频率。提高了理条机智能化、自动化程度,优化了理条工艺结果。(4)设计了基于ARM Cortex-M3内核微处理器与双模糊算法的茶叶理条机控制系统。结合实际工艺流程,在茶叶理条机上完成了温度与理条实验,对温度控制效果与理条效果进行评估。结果表明,基于双模糊算法与嵌入式技术的茶叶理条机控制系统有效减少了制茶过程中的人为因素干扰,提高茶叶理条品质及茶叶加工机械的智能化水平。本文结合实际制茶经验,提出并设计了一种基于模糊决策与模糊PID控制的茶叶理条机控制系统方案,进行了仿真与实验,得到了良好的锅槽温度控制与茶叶理条效果,为今后茶叶机械智能化研究提供了方法并扩充了研究思路。更多还原

【Abstract】 Since the 21 th century,with the continuous development and improvement of people’s living standard,their demand for tea quantity and quality has been growing very quickly.China is one of the most important tea producing and consuming countries in the world and has the largest green tea output.As the key process in green tea manufacture,the carding of tea plays an important role in green tea quality.The accuracy is not high enough and the fluctuation range is too large of temperature control.Also,tea carding processing depends on artificial experience too much and can not achieve the optimal parameters according to different situations.As a result,the appearance of tea will turn yellow and dark.It also will lead to burning smell.Aiming on above problems,tea carding parameter decision-making fuzzy controller and fuzzy PID temperature controller were designed based on the study on fuzzy algorithm,fuzzy PID control technology and computer simulation technology.And also design the hardware and software about tea carding machine control system.Make system simulation on computer and experiment on tea carding machine.The main work and achievements are as follows:(1)The tea carding technology and mechanical structure characteristics and working principle of carding machine applied in this paper are analyzed.Besides,it determines that the tea carding process is mainly in the stage of constant drying rate according to the material drying theory.The characteristics and basic control method of first order inertial control system with high inertia are analyzed.(2)A theoretical discussion on PID temperature control,fuzzy algorithm and fuzzy PID algorithm is used as the basis for design of a parametric fuzzy controller and fuzzy PIDtemperature control.Simulation of the Control system software and hardware was performed using Matlab/Simulink.Further experimentation made use of a Tea Carding Machine.(3)A new form of control system is proposed through utilization of a Tea Carding Machine based on embedded technology and fuzzy control technology: Tea humidity level,species and processing level are used as inputs for tea carding parameter decision.Improved accuracy of temperature control and reduction of variance.Differences between set and relative temperature is used as a correction mechanism for vibration frequency.The end result being a net improvement in tea carding machine automation and intelligence.(4)Design of a control system which can be implemented on a ARM Cortex-M3 kernel micro processor.Through combining tea carding processing technology,experiments were performed on tea carding machine.Assessed temperature control and tea carding processing results.Results show that a control system based on double fuzzy control algorithm and embed technology effectively reduces error from human interference during tea carding process.The new method improves tea quality and tea processing machine automation levels.This paper utilizes tea processing experience to propose and design a new tea carding machine control system based on fuzzy decision controller and fuzzy PID temperature controller for a better temperature control and end product.Results from this paper contribute to future automation of tea carding machine design.更多还原