基于CAN总线的污水处理鼓风曝气过程自适应控制系统的研究与设计

【作者】 谯刚；

【导师】 熊世和；

【作者基本信息】 电子科技大学 ， 机械电子工程， 2002， 硕士

【摘要】 本课题主要针对以一体化氧化沟为主体的污水处理鼓风曝气自适应控制问题，提出了基于CAN总线结构的污水处理的FDCS(现场总线式集散控制系统)模型，采用三个现场控制器与中央控制室构建了整个控制系统，并设计了基于CAN总线的分布式数据采集和控制系统，建立了氧化沟中溶解氧和pH值的数学模型，针对模型没计了两套自适应控制算法，最后对控制算法进行了数字仿真。 本课题在污水处理工艺部分结合近年来污水处理新技术和运行方式的讨论，提出一体化氧化沟技术的使用是现代污水处理技术发展的总趋势，分析了污水除氮脱磷工艺的演变及其创新所在，设计并优化了污水处理的总体工艺流程。 在总体设计部分通过对CAN总线的通信模型、技术规范以及帧结构和错误类型等内容的探讨，以及对自适应控制的原理、特征及类型的分析，针对基于CAN总线的污水处理自适应控制系统进行了总体设计，分析了硬件组成，并对该系统进行了结构设计，对中央控制室和各现场控制器分别进行了功能设计。 基于CAN总线的分布式数据采集与控制系统的设计部分主要给出了一种基于CAN总线的分布式数据采集与控制系统的设计与应用，阐明了它的工作原理，介绍了CAN总线的硬件接口电路设计，并对系统的整体结构、硬件配置、软件功能及各节点功能分别作了详细说明。 本课题还对现场控制器及相应的控制量(模拟量和开关量)、控制方式进行了设置，并主要针对氧化沟中的溶解氧和pH值模型这两个非线性系统分别设计了基于神经网络的PID自适应控制算法和基于带有约束的最小二乘控制算法，大大提高污水处理的效率并明显地降低了能耗，通过对算法的数字仿真，为控制模型及相应算法的进一步优化提供了充分的依据。 整个系统由于采用的3个现场控制器具有多主结构、很强的实时能力和高可靠性通讯，系统总体设计和局部设计都保证了系统具有高的性价比，并且针对一体化氧化沟控制器采用了高效率和高可靠性的自适应控制算法，因而整个FDCS具有很好的实时性、高效性、可靠性、开放性、经济性和可操作性。 整套系统的设计采用产业化的思路，在系统集成时充分考虑对现有污水处理厂的技改方案和科研成果的转化和产品化。以鼓风瀑气的全过程作为控制对象，建立控制对象的数学模型的研究工作在国内尚属首创，并为控制理论在污水处理过程控制的应用开创了新的领域。更多还原

【Abstract】 This thesis was focused on the problem of sewage processing in adaptive control that was based on integrated oxidation ditch, and produced the model of Field Distributed Control System based on CAN bus. It adopted three field controllers and central controller to construct the control system, developed the distributed data acquisition and control system based on CAN bus. It also constituted the mathematical models of dissolutive oxygen and pH value, and projected an adaptive control algorithm for each model, finally made signal simulation for the algorithms.In the technical part the thesis was based on the discussions in the new technology and the running mode of sewage processing. It produced that the usage of integrated oxidation ditch was the developing trend of modern sewage processing technology, analyzed the evolvement and innovation of the technique in eliminating nitrogen and phosphor, developed and optimized the whole flow of technique.In the part of whole designing the thesis discussed the communication model, technology criterion, frame structure and error types of CAN bus, and analyzed the principle, character and types of the adaptive control. It also gave the whole designing, and analyzed the hardware composition, at length gave the structure designing of the system and the function designing of the central controller and each field controller.In the part of distributed data acquisition and control system a field control system with CAN bus was developed based on integrated oxidation ditch in a sewage processing plant that was introduced. The CAN bus interface hardware was proposed here, and the overall architecture, hardware composition, software functions and the functions of each controller were discussed in detail.This thesis also set the variables and methods of controlling, developed the algorithms of PID adaptive control based on Neural Network and Least squares with restriction. They advanced the effectivity of sewage processing and lowered the waste of energy. Through the signal simulation of algorithms the thesis provided the sufficient basis for the optimizing of the controlling models and correspondent algorithms.The three field controllers of the system had multi-master structure, high real-time capability and high reliability communication. The whole and local designing of the system had the high ratio of capability and cost, and adopted high effective and highreliable algorithms, so the FDCS owned high real-time, efficiency, reliability, open, economy and expedient operability.The designing of the system adopted the idea of industrializition, viewed the technology reconstruct of the sewage processing plant and the product of the achievement in scientific research. This thesis regarded the whole process of blast and aeration as control object, and constituted its mathematical model, which was original in the civil. It also originated a new domain for the applications of control theory in the sewage processing.更多还原