Thermal power generating unit air volume and air pressure decoupled control method

Abstract

The invention discloses a thermal power generating unit air volume and air pressure decoupled control method. The method comprises the steps that: a primary fan outlet air volume serves as a total primary air volume, and an air feeder outlet air volume serves as a total secondary air volume; and the total secondary air volume serves as a total air volume in boiler combustion control, and the totalair volume of a boiler is controlled by controlling the total secondary air volume. According to the method of the invention, the total primary air volume is separated from the total air volume control; hot primary main pipe air pressure serves as a target value of the primary air control; the primary air pressure control logic is optimized, so that the primary air volume is indirectly controlledthrough controlling the primary air pressure, and meanwhile, the total secondary air volume serves as the total air volume in the boiler combustion control so as to be controlled; and therefore, thedecoupled control over the total primary air volume and the total secondary air volume in the total air volume is achieved. When the total primary air volume and the total secondary air volume are coupled, combustion is insufficient or pollutants exceed the standard, and a combustion effect is poor due to the unreasonable ratio of the total primary air volume and the total secondary air volume, with the the method adopted, the problems can be solved; and the combustion control effect of the boiler is improved.

Description

technical field [0001] The invention relates to the technical field of thermal power unit control, in particular to a decoupling control method for air volume and air pressure of a thermal power unit. Background technique [0002] Boiler combustion process adjustment is an important means to make the heat provided by fuel combustion adapt to the load requirements of the steam turbine and ensure the economical combustion and safe operation of the boiler. It is also one of the most important control links of thermal power units. In order to make the boiler achieve a better combustion effect and avoid the risk of boiler flameout caused by too low oxygen content, when the unit load changes, the control system will generally increase the total air volume entering the boiler first, and then increase the coal volume entering the boiler; When reducing the load, reduce the coal volume first, and then reduce the air volume, so that the air powder can be reasonably matched and the air ...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the above-mentioned technical problems existing in the air volume control of the existing thermal power units, the present invention provides an air volume and wind pressure decoupling control method, which can avoid the problem that the overall adjustment performance of the unit is affected by inaccurate local measurement or abnormalities, and significantly improve Control Effect of Boiler Combustion

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