【作者】 秦晓会；

【导师】 吕新民；

【作者基本信息】 西北农林科技大学 ， 农业机械化工程， 2009， 硕士

【摘要】 目前,我国的小型磨粉机喂料系统多数为气动伺服控制喂料系统,轧距的调节采用的是手动机械式调节机构,控制方式较为落后。现在面粉加工已经步入了“精细时代”,这对磨粉机的性能也提出了更高的要求,先进的控制方式对磨粉机整体性能的影响日渐显现。本文依据自动控制理论,采用单片机技术和传感器技术,研究、设计了小型磨粉机的自动化控制系统,该系统主要包括变频调速喂料的闭环控制装置和轧距自动调节闭环控制装置。按照系统的技术要求,基于PID控制原理构建了变频调速喂料和轧距自动调节的闭环控制模型。选择一般磨粉机的参数,进行了控制模型仿真分析,仿真结果证明了两个控制模型的正确性,同时得到了重要的控制参数。该控制系统采用了模块化设计方法,分别完成了磨粉机自动化控制系统的硬件及软件设计。硬件部分围绕MSP430F149单片机,对系统的输入输出、显示等外围电路进行了设计;选择低速永磁同步电机驱动喂料辊,采用变频调速技术,实现了磨粉机喂料系统的自动调速喂料;通过无刷直流电机驱动滚珠丝杠,带动磨粉机动辊与定辊离合,实现了磨辊的快速离合闸以及轧距的自动调节。软件部分通过对系统控制过程的分析,制定了软件控制策略;对系统任务进行了划分编排,并进行了优先级设置;根据模块化、结构化设计思想,进行了软件设计。另外,对控制系统进行了硬件和软件的可靠性分析,制定了相应的防范措施。小型磨粉机的自动化控制系统,提高了小型磨粉机的机电一体化水平,实现了自动化控制,这为小型磨粉机单机向组合机组发展打下了良好的基础。更多还原

【Abstract】 At present, a great number of feeding systems for the small roller mill are pneumatic servo-control system in China. And the control method of the distance regulation of the roller mill is manual adjustment. These control methods are lagging behind. Flour milling now has entered“Fine time”, which puts forward higher requirements for the roller mill’s performance. Advanced control methods on enhancing performance of roller mill increases obviously.The paper based on automatic control theory, studies and designs the automatic control system for the small roller mill by using of MUC technology and sensor technology. This control system mainly includes both frequency control feeding closed-loop control device and rolling distance automatic regulation closed-loop control device.According to the technical requirements of the control system, the closed-loop control models of frequency control feeding and rolling distance automatic regulation are built based on PID control principle. By the parameters of common roller mill, the control models are simulated and analyzed. The results show that the two control models are proper, and the important control parameters are got from simulating analysis.By using of the method of modular design, the paper separately completes the hardware and software design of the automatic control system for small roller mill. In the hardware part, the input/output, display and other periphery interface circuits are designed surrounding MSP430F149 MUC. The low-speed permanent magnet synchronous motor (PMSM) has chosen, and used of frequency control technology, realizes automatic speed regulation feeding.The ball screw has driven by the brushless DC motor (BLDCM), and then drives the moving roller and the stable roller of the roller mill closing up and loosening, and realizes the two rollers rapidly closing up and loosening and the roller distance automatic regulation. In the software part, according to the analysis of the control process of the control system, develops a software control strategy. The paper compartmentalizes and arranges the system tasks, and sets the priority for them. At last, completes the software design based on the modular and structured design methods.In addition, the paper has analyzed the reliability of the hardware and software of the control system, and made corresponding preventive measures.The automatic control system for small roller mill has increased the level of mechanical-electrical integration of small roller mill, and realized automatic control, which has laid a good foundation for small roller mill developing from single machine to combined unit.更多还原