The Research And Implementation Of Control Process Of Control System Of Wood Drying

Forest is one of the important nature resources of Earth, and is the guarantee ofhuman life. In the past, predatory exploitation of forest resources of human beingcaused a variety of ecological problems, which have been a threat to the environmentof human life. So, in order to ensure the environment, how to use the forest resourcesrationally and efficiently attracts more and more concern. The purpose of this paper isto research the control process of control system of wood drying, and in order toimprove the efficiency and reliability, uses the computer to collect the key parameterssuch as temperature, humidity and moisture instead of artificial operations. And,according to different drying stage, we adopt different control strategy to improve thelevel of wood drying, so that we can achieve automatic control of wood drying.Overall, main tasks are as follows.Introduce the background knowledgeThis part introduces the present research situation and the development trend ofdomestic and foreign in wood drying technology area. Then the target of the controlprocess of wood drying system is proposed. This part also demonstrates thebackground knowledge of wood drying, such as the definition and significance ofwood drying, the factor that effect the wood drying, the related terms of wood drying,the process of wood drying and so on. This knowledge laid the foundation of thedesign and implementation of entire system.Overall designThis part determines the design of the whole control system. The whole controlsystem can be divided into the PC monitor module, main control board module, themeasurement board and switch board module. Then this part determines the design ofthe data process software. The software can be divided into12interfaces. Then, thispart analyzes the theory of measuring humidity based on dry-bulb and wet-bulbtemperatures. And a theoretical formula is deduced for the calculation of relativehumidity from dry-bulb and wet-bulb temperatures. Through analysis of thetheoretical formula, a two-dimensional conversion table is produced to transform dry-bulb and wet-bulb temperatures into relative humidity. At last, this part introducestwo control schemes, one is based on dry-bulb and wet-bulb temperatures, the other isbased on paper.The implementation of systemThe data process software is development in C++builder. The software can bedivided into12interfaces, including: the conversion table of AD values to the woodmoisture, the conversion table of paper AD values to the equilibrium moisture, theauthor information and so on. In the part of implementation of control process, wefinally choose the STM32board be the hardware platform and choose the uCOS bethe software platform. This part introduces FATFS module, the set of drying standard,the implementation of method to measure humidity and the process of controlprocess.Debugging and summaryFinally, we debug the data process software and the wood drying system, and dothe error analysis of method to measure humidity. After several testing, data processsoftware completed the desired goals. The error of method to measure humidity iswithin the engineering calculation requirement. Wood drying control system can alsooperate reliably and stably to control the drying process, and reach the designedtarget.This paper implemented the wood drying system successfully, and the controlsystem is also studied. This paper has important theoretical significance and referencevalue to reduce the drying costs, achieve automatic control of wood drying, andensure the quality of wood drying.