大型火电厂制粉系统模糊控制策略研究

发布时间：2018-03-28 18:17

本文选题：制粉系统　切入点：球磨机　出处：《华北电力大学(北京)》2017年硕士论文

【摘要】：球磨机,在我国的火力发电行业,承担着重要的磨煤任务。因为在我国,火力发电仍然占据着发电行业的主流,所以作为为火力发电厂提供优质煤粉,以使其能最大化最高效最经济的利用资源的球磨机系统,其作用不容小觑。同时,球磨机的应用行业十分的广泛,不仅仅是在火力发电行业,在采矿行业、建筑行业、水泥行业等都发挥着重要的作用。球磨机投入工业生产已经几十年了,但是在对球磨机的控制问题上,一直没有很大的突破。因为球磨机系统自身的大迟滞性、非线性、强耦合性,使得在对其控制问题上变得十分困难。随着科技的进步,球磨机的设备也越来的越大型化、复杂化,但是在近几十年的工业生产中,尤其是火力发电行业,在我们国家很大一部分的火力发电厂中,球磨机的控制状态仍在人工运行操作阶段。人工操作球磨机,使得球磨机的磨粉质量不佳,造成资源的浪费,不符合当今时代提倡的能源节约。其次,人工直接操作如此庞大的机器设备,不可避免的会有安全事故出现。因此,在球磨机设备大型化的同时,将人们从直接的操作中脱离出来,同时能实现经济安全稳定的控制球磨机系统,是我们一直追求的目标。针对球磨机系统建立数学模型困难,许多现有的先进方法开始用于球磨机的控制问题。但是因为许多方法都需要了解对象的精确模型,导致球磨机的控制问题一直难以取得大的进展。模糊控制技术的诞生,解决了不能获得被控对象精确的特性、建模难的问题。本文结合球磨机自身的特点,对其各个系统进行了分析。利用模糊控制和PID控制联合控制的方法,即克服了球磨机建模难得问题,同时最大程度的利用专家和操作人员多年积累的经验,将这些宝贵的经验设计进入模糊控制器。联合PID一起控制的主要目的就是,对于小的误差处理使用PID,当误差大于预先设定的界限值时,自动转换使用模糊控制器。这种联合控制克服了模糊控制器单一控制的疲劳工作,通过仿真分析也证明了,比单一模糊控制器和单一的PID控制效果更佳明显,球磨机的运行更加稳定。
[Abstract]:Ball mills, in China's thermal power generation industry, undertake an important task of coal grinding. Because in our country, thermal power generation still occupies the mainstream of the power generation industry, so as to provide high quality pulverized coal for thermal power plants, The role of the ball mill system, which can maximize the most efficient and economical use of resources, is not to be underestimated. At the same time, the ball mill is used in a wide range of industries, not only in the thermal power industry, but also in the mining industry and the construction industry. The cement industry is playing an important role. The ball mill has been put into industrial production for decades, but there has been no great breakthrough in the control of the ball mill, because of the large hysteresis and nonlinearity of the ball mill system itself. With the progress of science and technology, the equipment of ball mill is becoming larger and more complicated, but in recent decades of industrial production, especially in the thermal power industry, In a large part of the coal-fired power plants in our country, the control state of the ball mill is still in the stage of manual operation. Manual operation of the ball mill makes the grinding quality of the ball mill poor, resulting in a waste of resources. It is not in line with the energy conservation advocated in the present age. Secondly, it is inevitable that there will be safety accidents when direct manual operation of such huge machinery and equipment occurs. Therefore, while the ball mill equipment is becoming larger, It is a goal we have been pursuing to separate people from direct operation and to realize economic, safe and stable control ball mill system. It is difficult to establish mathematical model for ball mill system. Many existing advanced methods have been applied to the control problems of ball mills. However, because many methods need to know the exact model of the object, it is difficult to make great progress in the control problems of ball mills. In this paper, the system of ball mill is analyzed, and the method of fuzzy control and PID control is used to control the system. That is to say, it overcomes the rare problem of ball mill modeling, and at the same time, makes the most of the experience accumulated by experts and operators over the years, and designs these valuable experiences into fuzzy controller. The main purpose of joint PID control is, For small error processing, PID is used. When the error is greater than the pre-set limit value, the fuzzy controller is used automatically. This joint control overcomes the fatigue work of the single control of the fuzzy controller, and it is also proved by simulation analysis. Compared with the single fuzzy controller and the single PID control, the operation of ball mill is more stable.
【学位授予单位】：华北电力大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP273.4;TM621

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