【作者】 杨凤艳；

【导师】 唐宗军；

【作者基本信息】 沈阳工业大学 ， 机械电子工程， 2006， 硕士

【摘要】 温度是工业生产、科学研究中常见和最基本的工艺参数之一,温度控制广泛应用于社会生活的各个领域。传统的控制方法多采用PID控制,但PID的参数不易实现在线调整,特别是用在高精度温度控制时,由于存在外界因素的干扰,严重地影响了控制的品质。 随着科学技术的进步,控制理论也在不断地发展,模糊控制是一种正在兴起的控制技术。模糊控制不需要装置的精确模型,仅依赖于操作人员的经验和直观判断,非常容易应用,并且模糊控制对被控对象参数变化有强鲁棒性,对控制系统干扰有较强抑制能力。本文在分析国内外温度控制系统的基础上,针对拉伸机保温腔的特点,提出了以PLC为中心,在温度控制中应用模糊控制技术,从而有效提高温度控制精度,满足温度控制的需求。 本文以双向拉伸机的保温腔为研究对象,完成了对整个温度控制系统的开发设计。通过分析可知,温度是一种不确定、大惯性、非线性严重的控制对象,本文采用模糊控制策略实现温度控制,其具有控制对象参数不敏感,与PID控制相比超调小等显著特点,从而使系统取得较好的控制品质。双向拉伸机保温腔温度控制系统为强耦合多变量温度控制系统,系统是以中央温度和均匀温度作为输入,以加热炉功率和风机速度作为输出,形成了双输入-双输出温度控制系统。根据这些特点本文采用具有解耦功能的模糊控制器,提出了分段控制算法,成功地进行了温度控制。文中主要介绍了控制理论的产生、发展以及控制算法的步骤,并从技术上分析、研究设备的控制系统、温度控制器、加热元件、温度传感器、以及变频调速控制系统等的选择和确定,并进行了软件编程。实践表明该系统切实可行,达到了所要求的控制精度。更多还原

【Abstract】 Temperature is a common and one of the most basic process variables in industrial production, scientific research and daily life. Temperature control exists widely in every aspect of social life, and PID is the mainly adopted control algorithm in practice. Due to the environment variation PID parameters in-process tuning is not attainable, which negatively effects control quality.Control theory is ceaselessly updated with the development of science and technology. Fuzzy Control is newly emerging control technology. Fuzzy control needs not the exact mode of equipment but experiences and intuitional judge of the operator. It is easy to be used, fuzzy control is big robust to the parameter of the controlled object and has the strong restrain ability to disturb the system. Based on the analyses of temperature control system both inside and outside, aiming at the characters of the heat preservation of the bidirectional pull machine, this paper presents the whole system’s design. PLC is the core, uses fuzzy control in the temperature system, so it can effectively improve the control precision and adapt to the different temperature’s requirements.The research object is the heat preservation of the bidirectional pull machine, finish the exploitation and design of the whole temperature control system. By analyzing, the control temperature in the machine is an uncertainty, big inertia, and serious non-linearity object. So the fuzzy control was adapted to realize the control, because it had a thick skin to controlled object’s parameters and a less exceed amplitude modulation than PID.This paper shows a strong coupling and multiple variable temperature control system, it’s input variables are center temperature and average one, and the output variables are heating components and hot wind’s velocity, these form a double input-double output temperature control system. Based on these, fuzzy control method that can decoupling is used, divided control arithmetic is given. The control arithmetic steps are introduced. It is a practical plan and reaches the temperature control quality.更多还原