【作者】 郑美容；

【导师】 左为恒；

【作者基本信息】 重庆大学 ， 控制理论与控制工程， 2009， 硕士

【摘要】 随着社会经济的迅速发展和世界能源的紧张,工业和城市居民对供水质量和供水可靠性的要求不断提高,利用先进的自动化技术、控制技术,设计高性能、高节能、能适应不同领域的供水系统成必然趋势。本论文首先通过阅读国内外相关文献,总结了国内外变频恒压供水系统的发展现状以及控制理论在变频恒压供水控制系统中的应用,通过分析变频供水系统的基本特性和变频调速原理,阐述了水泵变频运行的节能原理,分析不同压力控制点的影响,确定采用用户端恒压控制方式,提高供水可靠性,总结了供水系统的主要特点。其次,研究了现阶段恒压供水闭环控制的几种方案,其中模糊自适应PID控制器结合了模糊控制和PID控制各自的优势,对控制效果改善较为明显。但是目前绝大部分的模糊自适应PID控制器都是基于Z-N或其它工程整定方法整定出的PID初值,结合专家经验知识建立的模糊控制规则进行PID参数的在线自调整。而Z-N方法整定出的PID超调量大,调节时间长,专家知识建立的模糊控制规则,其主观性强,性能不一定最优,且对模糊控制规则的调节复杂、烦琐。因此,本文就这两个方面对模糊自适应PID控制器进行改进。文中详细论述了遗传算法的基本原理,并利用遗传算法进行控制器初值的整定。仿真结果表明,利用遗传算法对控制器初值进行整定后,超调量大大减小,调节时间缩短,系统较快进入稳定。然后,利用整定出的这组性能较为优良的控制器初值,结合专家知识建立的规则,进行了模糊自适应PID控制器的初步设计,并进行了仿真。但是初步仿真结果发现利用专家技术工程知识建立的模糊控制规则对本系统不是很合理,需要进行调整。鉴于147条模糊规则的调整是复杂而烦琐的,而目前对这方面的研究还较少,且大多采用遗传算法进行优化,但遗传算法在交叉运算中易产生大量不可行解,易破坏好的个体,使算法效率低下,因此本文提出采用禁忌搜索算法对模糊规则进行优化。最后,详细论述了禁忌搜索算法的基本原理及设计过程,对禁忌搜索算法优化模糊规则的编程实现进行了详细的说明。利用优化前后的模糊自适应PID和PID控制器对供水系统进行仿真对比分析。仿真结果表明,优化规则后的模糊自适应PID控制器性能最佳,超调量小,抗干扰能力强,鲁棒性较好,提高了系统的动、静态特性。更多还原

【Abstract】 With the rapid development of social economy and seriously lack of energy resource, it demands the better quality and reliability of water supply system. With the help of advance techniques of automation, control and communication, it is inevitable tendency to design water supply system which has high function and saves energy well. At the same time this system can adapt different water supply fields.First, this thesis summarys current development situation and application of control theory in water supply system in China and abroad, then analyzes characteristics of water supply system with variable-frequency and principle of frequency control. It expatiates on energy conservation theory of frequency control, and then it takes user side as pressure control point because the system is more reliable by it.Second, after doing some research, fuzzy-PID is determined to be taken because of its superiority. Nowadays, most of fuzzy-PID controllers are designed with initial parameters by Z-N, using fuzzy control rules by expertise. But the system’s overshoot is big, and adjusting time is long using PID with initial parameters by Z-N. And it’s subjective to build control rules based on expertise. Therefore, the paper improves fuzzy-PID in these two aspects. Then it introduces principle of GA, and sets initial parameters of PID by GA. The result indicates that overshoot is reduced and adjusting time is curtailed. Then, with this group of parameters as initial parameters, and fuzzy control rules using expertise, a fuzzy-PID controller is designed preliminary. The simulation result is not ideal. Fuzzy rules directly determine performance of control. It’s too intricate to adjust 147 fuzzy rules, and research about it is less. Most of them optimize fuzzy control rules by GA. But GA generates too many infeasible solutions, and destroys good genes easily. Algorithm efficiency is low. So another method to optimize fuzzy rules is put forward by Tabu Search Algorithm.Finally, it discourses fundamental principle and design progress of Tabu Search Algorithm. Also it explicates how to optimize fuzzy rules using Tabu Search Algorithm by Matlab. It makes use of PID and fuzzy-PID with and without optimized fuzzy rules to contrastive analysis. The result indicates that fuzzy-PID with optimized fuzzy rules is better than others, with less overshoot, better ant-jamming capability, better robustness.更多还原