| Beer production is one of traditional industry in our country. With the development of civil economy and the improvement of demotic living condition, beer industry has also been rapidly improved. In the recent two decades, the yield of beer products has mounted up to more than 30 times. But still, because of the complex technology of the beer production, there are many drawbacks, such as behindhand technical equipments, rare application of automation, instable product quality, etc. How to improve the integrated automation level in beer production becomes a urgent research project. Thus, this thesis investigates the integrated automation level and its application technology based on beer production process. It has important practical meaning to apply high technology to traditional industry and improve its integrated technical level.Following is the main contribution of the thesis.A. Based on beer production technology and its control demand, this article investigates the control on a class of long time delay and time varying plants, which is delegated by beer fermentation temperature. It is the difficulty and central problem of automation in beer production process. The simple PID feedback control and the robust stability of predictive control are firstly discussed in this paper. Then, it brings forward the PID controller design method based on loop shaping idea, 2-DOF predictive control method and the criterion of robust stability limit of smith predictive control system, which have excellent practicality value.B. Found in actual applications, there are theory and technical limits to obtain the precise model of beer fermentation plant. So, It is difficult to realize precise control on beer zymotic temperature through single control pattern or control strategies based on models. In this paper, M-PID control strategy is firstly brought forward, which breaks through single control pattern and is independent of mathematic model. It exhibits high robustness and ideal quality to control long time delay and time varying objects. At present, M-PID control strategy has applied in actual beer fermentation plants and obtained an excellent success. The control precision is located in ?.3癈, which isimportant to improve the beer quality and integrated automation level of the whole beer industry.C. This article brings forward combined PID strategy to control the other kind of temperature control objects such as mash boiler. It is aimed to resolve the overshooting and servo track of temperature control in saccharifying process. The combined PID control strategy has also applied in actual plants. Its absolute error is less than ±0.3℃, there is hardly any lag between response curve and set curve.D. Another main difficulty in controlling the temperature of beer fermentation pot is the precisely measurement of fermentation temperature. Since fermentation temperature fluctuates just in a small range (-1-15℃ in general), the measurement error will be large if using ordinary Pt100 to measure fermentation temperature. Furthermore, a large amount of dew will yield in the protective tube and dew yielding may cause Pt100 instable. In order to solve the problem, we exploit the SBWJ temperature transmitter that is specially used to measure beer zymotic temperature. The SBWJ temperature transmitter has high precision, stable quality, long life-span. Especially, it can protect from dew efficiently. Up to now, more than 1000 transmitters have successfully applied in various beer fermentation pots. It was awarded the national invention patent (ZL 97105253.0) in March 2000.E. Based on the measurement and control demand in beer production process, we develop independently many kinds of software that has independent property right. All obtain an excellent application success.Based on above contribustions, we have developed many kinds of computer control management systems successfully, which integrate the automation technology, information management technology and network technology. All of them adopt the mo...
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