锅炉三冲量（Three impulse of boiler）.doc

锅炉三冲量（Three impulse of boiler） Introduction to process control requirements. (1) the boiler drum liquid level is the main process index to represent the production process, and it is also one of the main conditions to ensure the safe operation of boiler. The level is too high, so that the steam produced liquid, not only reduce the yield and quality of steam and hot air will make the scale, or the steam turbine blade damage; when the liquid level is too low, it will affect the balance of water vapor, while dry boiler, leading to serious boiler explosion, directly endanger their personal safety accidents, major equipment etc.. The boiler drum level control is a big bottleneck problem that restricts the process safety, stability, length, production and production. (2) the concept and specific meaning of impulse: the so-called impulse is actually variable, the impulse in multi impulse control refers to the measurement signal introduced into the system. In the boiler control system, the three impulse refers to the drum level LIA2104, the steam flow FAQ2102, and the feed flow FA2101 three measuring signals, in which the drum level LIA2104 is the main impulse. (3) the introduction of the three main reasons: the impulse of drum level LIA2104, FAQ2102, water flow and steam flow FA2101 three measurement signal, after the operation, a common control valve; the drum signal is controlled variable, is the main index to reflect the working state of the boiler, but also to ensure the safe operation of the boiler steam into the necessary index; a traffic signal is to influence the timely steam flow fluctuation on the drum level, and effectively false level phenomenon caused by the misoperation of the control system; introducing the water flow signal to water flow signal as side variables, to overcome the interference of rapid and timely overcome water pressure change on the drum level by the sub loop cascade control system. Two, system control block diagram, boiler drum liquid level