Redrying Machine Intelligent Control System Study

To redry the tobacco leaf is a process in which the tobacco leaves become into the material of cigarette from farm produce .It plays a very important role in the process of making cigarette. When the baked tobacco leaves is baked again, then the redried tobacco leaves can be obtained .It has many advantages: the ratio of the broken leaves will be reduced greatly; The cigarette factories can get the high quality and standard material ;It also helps to store the leaves for a long time and does good to alcoholizing, so a lot of money will be saved. At present time, the main products are the leaves and stems in the international trade. Therefore, the profit of the cigarette is in the hand of the quality of the redried tobacco. Especially, after we have joined the WTO, more and more merchandises will be traded. If there is one percent above or below the standard about the containing water for one dan tobacco leaves, one hundred RMB will be lost .For Baofeng tobacco redrying factory, which has a product capacity of 30 dan, several million RMB is lost every year .So it is necessary to improve the automatic control system.We set up the physical model for the redrying segment and statically model for the ordering model according to their characters, after we learned the technical skill of the redrying machine. Then we get the factors, which affect the temperature and humid of the tobacco.The tobacco redryer is a plant, which has a large lag and multiple parameters, non-linear feature. So it is very difficult to control .the traditional control cannot qualify because it requires the exact model to control. Intelligence control, such as the fuzzy control, expert system and learned control, become a powerful tool to solute the plant that has an unclear model. However, if we give up the method of the traditional control, it means that much important information has been wasted.According to our experience, we should combine the traditional control and 1C. In this paper, we introduce the MFC based on ANN.MFC is a control method based on the model, which was put forward in 1770s. It has three parts: model predicting, continual optical and backward. Model predicting is to setup the model according the input and output data. For the linear system, it is very easy and difficult for the nonlinear system. In the paper, we use the FNN to predict themodel, which combine the advantages of fuzzy and ANN. We present a four layers FNN. which has a clear meanings and simple calculation.According to its simulink programmed by C++, we analyze its result and it proofs that this arithmetic can satisfy our requirement. Then we give the supervision interface using the configure software. In the whole design of physics structure to realize the control idea, we introduce the advanced field bus of SIEMENS PLC in order to update the control system in the future. According to the spectrum experiment, we select 1. 94um as the measure wavelength. Other hardwires are also selected.Briefly, what we have done is to design a control system which can guarantees the redryer work calmly, combining the traditional control method and intelligence control, making the advantage of the field bus as the physical form, controlling each subsystem separately by dividing the whole system into 12 subsystems.