毕业设计（论文）-300MW发电机组再热汽温控制系统设计精选.doc

摘 要 本次毕业设计(论文)的题目是铁岭电厂300MW机组再热气温控制系统设计。通过对机组的再热汽温控制系统进行现场实地观察、原理分析、可靠性论证，从而提出保证该系统长期稳定处于协调控制的方案。 在大型机组中，新蒸汽在汽轮机高压缸内膨胀做功后，需再送回到锅炉再热器中加热升温，然后再送入汽轮机中、低压缸继续做功。采取蒸汽中间再热可以提高电厂循环热效率，降低汽轮机末端叶片的蒸汽湿度，减少汽耗等。为了提高电厂的热经济性，大型火力发电机组广泛采用了蒸汽中间再热技术。 再热蒸汽温度控制的意义与过热蒸汽温度控制一样，是为了保证再热器、汽轮机等热力设备的安全，发挥机组的运行效率，提高电厂的经济性。再热蒸汽温度控制的任务，是保持再热器出口蒸汽温度在动态过程中处于允许的范围内，稳态时等于给定值。 在再热蒸汽温度控制中，由于蒸汽负荷是由用户决定的，所以几乎都采用改变烟气流量作为主要控制手段，例如改变再循环烟气流量，改变尾部烟道通过再热器的烟气分流量或改变燃烧器（火嘴）的倾斜角度。 关键字 再热汽温，过热蒸汽，串级 Abstract This graduation project (paper) is through the hot steam warm control system carries on the principle analysis, the reliable proof, the scene again to the TieLing three electricity 300MW units on the spot observes, guarantee this system which proposed long-term stability is in the coordination control the plan. In the large-scale unit, the new steam inflates the acting after the steam turbine high pressure cylinder, must again return to the boiler reheater in heats up elevates temperature, then sees somebody off again in the steam turbine, the low pressure cylinder continues the acting. Adopts among the steam hot to be possible to enhance the power plant circulation thermal efficiency again, reduces the steam turbine terminal leaf blade the steam humidity, reduces the steam consumption and so on. In order to enhance the power plant the hot efficiency, the large-scale thermoelectricity generation unit has widely used among the steam again the hot technology. Again the hot vapor temperature control significance and the superheat vapor temperature control is same, is in order to guarantee thermal energy equipment and so on reheater, steam turbine securities, the display units operating efficiency, enhances the power plant the efficiency. Again the hot vapor temperature control duty, is maintains the reheater to export the vapor temperature to be in the permission in the dynamic process in the scope, when stable state is equal to the given value. In again hot vapor temperature control, because the steam load is b