Fluidized bed boiler air input capacity control method based on model online identification

Abstract

The invention discloses a fluidized bed boiler air input capacity control method based on model online identification. The method comprises the following steps that according to the actual running condition of a fluidized bed boiler, the air input capacity is selected to serve as input of an online identification model, and material bed temperature of the circulating fluidized bed boiler serves as output of the model; a mathematical model of a single-input and single-output linear constant stochastic system is set up to enable the quadratic sum of fitting residual to be minimum, the model is identified on the basis of a weighted least square method of a rolling time window, and a material bed temperature value is output; a fuzzy control strategy is adopted for controlling the air input capacity, the obtained material bed temperature value is compared with an expected material bed temperature value to obtain input of the fuzzy controller, output of the controller is obtained after fuzzy inference is carried out, and the air input capacity is adjusted according to the air input capacity. According to the method, the model set up on the basis of the weighted least square method of the rolling time window is online, and therefore in comparison with an offline model, the material bed temperature can be identified better and can be more accurate than that of traditional modeling.

Description

technical field [0001] The invention relates to a method for controlling the induced air volume of a fluidized bed boiler based on model online identification. Background technique [0002] In recent years, my country's industry has developed rapidly, and the speed of industrial development has greatly exceeded the growth rate of energy, and the energy supply is very tight. my country is one of the countries that produce and use the most boilers in the world. Boilers are not only important thermal power equipment, but also extremely energy-consuming equipment, which consume a large amount of raw coal every year. At present, boiler efficiency is not high, and energy waste is quite serious. At the same time, boiler combustion emits nitrogen oxides, sulfur dioxide, smoke and other pollutants, seriously polluting the atmosphere, and has become one of the main sources of air pollution in my country. Introducing advanced modeling and control theory into the complex boiler combu...

AI Technical Summary

Problems solved by technology

[0009] 1. The operator is too subjective;

[0010] 2. The operator's operation has obvious hysteresis;

[0011] 3. The combustion rate cannot reach the ideal maximum value, wasting energy

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