啤酒发酵过程的微机控制.doc

啤酒发酵过程的微机控制 摘 要 在啤酒发酵中，温度糖度和时间三者的变化是相辅相成的。而实际上糖度的控制是由调节发酵温度来完成的。时间的控制，在一定麦汁浓度酵母数量和活性的条件下，亦取决于发酵温度。所以说目前的发酵操作中，最主要的是温度的控制。要使整个发酵过程按预定曲线进行，达到良好的产品质量，对麦汁发酵过程的温度进行控制，是十分重要的。单片机控制啤酒发酵的过程控制系统采用了集成电路温度传感器和优化采样控制，具有了较好的控制精度，稳定性和可靠性。而且由于其控制功能要通过内部的控制系统来实现，人们只要改变这些程序就可以更改系统的控制功能，以适应新的研制要求而不需要改变硬件系统。 本文介绍了一种把单片机应用在啤酒发酵过程中的控制系统。具体介绍了该系统涉及的对象特性，发酵温度的测量与控制，以及该系统的软件框图设计。 我们选择MCS—51系列的80C31作为CPU，构成一个最小系统机。系统机的特点是开发量大，应用灵活。整个系统的硬件主要包括：微处理器（80C31）和外扩存储器（27512、62256）及外扩I/O接口、译码电路、A/D转换器（AD1674JN）、D/A转换器（DAC0832）、LCD液晶显示器（ZJM12864B）、提供±12V和+5V的电源、4*4键盘、由PT100铂电阻构成的温度传感器、后向通道V/I变换电路、可调流量阀、开关阀。控制算法选用PID控制算法。 关键词 温度控制 PID 液晶显示器 集成电路 采样控制 Beer fermentation process of microcomputer control Abstract In beer fermentation, the sugar content and timing of temperature changes in the three complement each other. In fact the control of sugar fermentation by adjusting the temperature to complete. Time control, to a certain number of wort concentration and activity of yeast conditions, also depends on the fermentation temperature. So the current operation of the fermentation, the most important one is temperature control. Fermentation process to make the whole curve as scheduled, a good product quality, on the temperature of wort fermentation process control is very important. This article introduced one kind the monolithic integrated circuit application in the beer fermentative process control system. Introduced specifically this system involves object characteristic, fermentation temperature survey and control, as well as this system software diagram design. We choose MCS-51 series 80C31 to take CPU, constitutes a smallest system machine. The system machine characteristic is develops the quantity to be big, the application is flexible. The overall system hardware mainly includes: The microprocessor (80C31) and outside expands the memory (27512, 62256) and outside expands the I/O connection, the decoding circuit, the A/D switch (AD1674JN), the D/A switch (DAC0832), the LC