PID疗养器的疗养过程及其参数的整定方法.docVIP

摘 要 锅炉汽包水位是锅炉运行中的一个重要的监控参数，它间接反映了锅炉蒸汽负荷与给水流量之间的平衡关系。汽包锅炉给水自动控制的任务是使锅炉的给水量适应锅炉的蒸发量，以维持汽包水位在规定的范围内。由于给水系统的复杂性，现有的火电厂全程给水控制采用传统的PID控制，其精确数学模型难以建立，并且系统具有大滞后、时变性等一系列特点，往往难以满足火电机组复杂工况要求，所以许多大型火电厂对现有的全程给水控制提出了优化方案。 本文首先对控制系统进行时域分析，然后介绍PID调节器的调节过程及其参数的整定方法。重点分析了锅炉的给水控制系统，针对汽包水位控制对象的动态特性表现为有惯性、无自平衡能力的特点，采用先进的智能控制算法之一的模糊控制对其进行控制，并利用MATLAB分别对常规PID控制和模糊PID 串级控制进行仿真，结果表明采用模糊PID串级控制方法比常规PID控制方法迟延小、超调量小，使得汽包的动态特性得到优化。 关键词：模糊控制；给水控制；PID控制 Abstract The steam drum water level of boil is important monitoring parameter in a boiler movement, it had reflected indirectly the balance relations between the boiler steam load and the discharge of water. In the steam drum boiler for the water automatic control duty to adapt the boiler transpiration rate for the water volume, maintains the steam drum water level in the stipulation scope. As a result of for the water system complexity, the existing thermoelectric power station entire journey for the water control adopt the traditional PID control, its precise mathematical model establishes with difficulty, when the system has the big lag, denatured and so on a series of characteristics, often with difficulty satisfies the thermal power unit complex operating mode request, therefore many large-scale thermoelectric power stations proposed the optimization plan to the existing entire journey for the water control. First this article has analyzed the time domain of control system, then introduces the PID regulator’s adjustment process and the parameter installation method. And has analyzed great emphasis on the boil for the water control system, the steam drum water control object show the inertia, the non-self regulation ability, uses of a fuzzy control to control it, and separately carries on the simulation using MATLAB to the tradition PID control and the fuzzy PID cascade control, With comparing using the fuzzy PID cascade control method obtain result that is delay slightly, over small, enables the steam drum the dynamic characteristic to obt