600MW机组给水自动控制毕业论文.docVIP

中文摘要 目前，大型火电单元机组都采用机、炉联合启动的方式，锅炉、汽轮机按照启动曲线要求进行滑参数启动。随着机组容量的增大和参数的提高，机组在启停过程中需要监视和控制的项目也就越来越多，因此人工操作、监视的方式已远远不能满足运行的要求，而必须在启停过程中实现自动控制。这就需要有全程控制系统。 汽包锅炉水位是锅炉运行中一个重要的监控参数。它间接的表示了锅炉蒸汽负荷和给水量之间的平衡关系。维持汽包水位正常是保正汽轮机和锅炉安全运行的重要条件。锅炉汽包水位过高，会影响汽包内汽水分离装置的正常工作，造成出口蒸汽水分过多而使过热器管壁结垢，容易烧坏过热器。汽包出口蒸汽水分过多，也会使过热气温产生急剧变化，直接影响机主运行的安全性和经济性。汽包水位过低，则可能破坏锅炉水循环，造成水冷壁管烧坏而破裂。 本论文结合元宝山发电厂的实际情况对其给水系统进行了全程控制设计，论文比较详细的论述了控制系统的工作原理及特点，控制对象的动态特性，控制系统的构成以及具体的控制方案与策略。 关键词：给水全程控制系统、汽包水位控制、串级三冲量控制 Abstract Current, large fire electricity unit machine a way for all adopting machine, boiler uniting starting, boiler, vapor a machine according to start the curve request proceed the slippery parameter starts.Along with the aggrandizement of the machine a capacity with the exaltation of the parameter, machine an item for in start and stop process needing keeping watch on with control too more and more, the for this reason artificial operates, the monitoring way cant satisfy the request of the movement already and far and far, but must realizes in start and stop process the auto control.This need the whole distance control system. The vapor a boiler water level is a boiler to circulate inside to supervise and control the parameter importantly.It meant indirectly that the boiler steam carries with the equilibrium relation of the amount of water applied.Maintaining the vapor a water level normal is an important term to protect the positive vapor a machine to circulate with the boiler safety.Boiler vapor a water level over high, will affect the normal work that vapor an inside soda separate equip, making exit steam humidity excessive but made the hot machine take care of the wall knot dirty mark, burn easily bad over hot machine.A safety for exporting steam humidity excessively, and also would making hot air temperature producing nasty upheaval turning, directly affecting machine lord circulating with economic.Vapor a water level over low, then may break the boiler water circulates, resulting in