双交叉限幅控制在加热炉燃烧控制系统中的应用.doc

双交叉限幅控制在加热炉燃烧控制系统中的应用 摘要 本文鞍钢大型厂加热炉燃烧鞍钢加热炉为加热炉，预热段、加热段、均热段温度的优化设定和自动控制 设计中采用双交叉限幅控制燃烧的自动控制以炉膛各段的温度作为调节信号，控制煤气调节阀的开度，保证相应的燃烧所需煤气的量；同时煤气流量作为调节信号，按最佳空燃比控制空气调节阀开度，保证相应的燃烧所需的空气量。采用了双交叉限幅控制方式提高系统空燃比的稳定性，增强炉温的控制效果节能和 设计中采用美国AB公司的Logix5000系列组成分散控制系统检测和控制实现了计算机监控和数据采集，解决加热炉燃烧过程普遍存在的能耗高，钢坯温度波动严重，温度控制精等问题。关键词：加热炉，双交叉限幅，控制器温度控制The Application of Double Cross-Limit in the Control System of Reheating Furnace Abstract The main research of this paper is about the An Shan Iron and Steel Company large-scale factory reheating furnace combustion control system. The An Shan Iron and Steel Company Large-scale Factory reheating furnace is the walking beam reheating furnace, divides into the preheating station, the heating zone, the even heating station along the length direction. According to the technological requirements, the reheating furnace examination and the control system are divided into the reheating furnace temperature control, the examination system, the combustion air, the combination gas pipeline pressure control, the examination system, the vaporization cooling control system and so on. Each section of temperature optimized hypothesis and the automatic control in the reheating furnace are the primary controlling goals. The system has used the double-cross limit control principle realization reheating furnace burning automatic control. The system put each section temperature as the adjustment signal，controlled gas regulating valve opening, and guaranteed corresponding gas the quantity which burning needed. At the same time, put gas flow as regulating signal, control opening degree of air regulating valve according to the best burning ratio. After applying double-cross limit control mode, it can reduce the emission of noxious gas. It can also achieve the energy conservation and the environmental protection goal. Besides, it can improve the stability of air-fuel ratio and the effect of the furnace temperature controlling in the system. The system applies the Control Logix500