【作者】 左爱武；

【导师】 方康玲；

【作者基本信息】 武汉科技大学 ， 控制理论与控制工程， 2004， 硕士

【摘要】 蒸氨生产主要是将来自鼓风冷凝岗位的剩余氨水在蒸氨塔内进行蒸馏处理，使剩余氨水中的挥发氨蒸出后送回到煤气中以增加煤气含氨量进而提高硫酸氨的产量，并将蒸氨废水送至生化污水处理工序进行处理。因此，蒸氨工序生产不正常，不仅硫氨工序的产品有可能不合格，而且会直接导致生化工序的不正常，致使焦化厂总排超标。而保持整个氨塔生产稳定的指标就是塔顶的温度，为了保持生产稳定，一般塔顶温度应控制在103～105℃。但由于氨塔温度控制属于典型的大时滞系统，对这种系统的自动控制一直是焦化生产控制中的一个难题。 本文根据武钢焦化厂蒸氨系统的改造情况，采用西门子公司的S7-300系列PLC设计开发了蒸氨控制系统，将整个系统的温度、流量、液位、压力等18个工艺参数纳入监控，并根据工艺要求对其中的9个工艺参数进行闭环控制。 针对蒸氨系统中中间槽液位和氨塔进料量相互影响的特点，在总结生产职工操作经验的基础上，设计了蒸氨系统专家协调控制方案。 本文在对PID控制进行深入分析后，结合工程实际，针对大滞后、时变系统的特点将模糊控制与PID控制结合起来设计了一种PID参数模糊自整定的控制算法，并将之应用于蒸氨塔塔顶的温度控制中去。 PID参数模糊自整定系统主要由参数可调整PID控制器和模糊控制器两部分组成。它是在常规PID控制器的基础上，以误差e和误差变化率c作为输入，采用模糊推理方法对PID参数K_p、K_i、K_d进行在线自整定，以满足不同e和c对控制器参数要求，而使被控对象具有良好的动、静态性能。 对本文所设计的PID参数模糊自整定控制器进行了仿真实验，并将专家协调控制方案和PID参数模糊自整定控制器结合起来，在EFPT过程实验装置上完成了锅炉温度控制实验，以模拟蒸氨塔顶的温度控制过程，仿真和实验结果表明了本文所述方法的有效性。更多还原

【Abstract】 Ammonia distilling is to distill the residual ammonia from the blast section in an ammonia still, which evaporate the wolatile ammonia into the saturator to increase the production of vitiol ammonia and send waste water to biochemistry section to decontaminate. Therefore, if it is abnormal in ammonia distilling section, the production of vitiol ammonia will be unqualified and the biochemistry section will be abnormal too.which will leads the transnormal of sewage let. And the key to keep the distilling stable is the tempratue at top of the tilling tower, the temperature must be controlled between 103℃ and 105℃ in order to keep the distilling stable. But distilling tower temperature control is a typic big time-lag system, and the control of it is always a difficult problem in coak producing industry.This paper desighs an ammonia distilling control system with S7-300 PLC of SIEMENS Corporation based on the rebuilding condition of the ammonial distilling system of Wugang Jiaohua Corporation, which monitors eighteen technics parameters including temperatures pressures liquid levers and fluxs and controls nine parameters of them.According to the characteristic that the liquid surface of the trough and the ammonia water folw-in ammout affect each other, after summarizing the experience of the operating wokers, a intelligent expert control algorithm is propsed.Taking the engineering facts into account, according to the characteristic of big timelag system, this paper conbiles PID control and fuzzy control and designs a kind of fuzzy sef-tunning PID control algorithm, and then applys it in the control of temperature at top of distilling tower.The fuzzy self-tunning PID control system consists of two parts which are parameter adjustable PID system and fuzzy control system. Its inputs are error e and error change ec and adust its PED parameters kp , kt, kd online with fuzzy induce method based on the normal PIDcontroller. It can fulfill the command of different e and ec for PID parameters, which gives the controlled object a better static and dynamic performance.A simmulating experiment is made with the fuzzy self-tunning PID controller designed in this paper in MATLAB, the intelligent expert control algorithm and the fuzzy sef-tunning PID control algorithm are combined in the paper to make a experiment to sumulate the real ammonia distilling process with the EFPT pocess apparatus, the result shows the validity of the approch proposed in this paper.更多还原