The combustion process in the working space of a heat installation is simulated. The static characteristic of the dependence of fuel consumption on air consumption in the conditions of stabilization of heat generated as a result of the combustion process is shown, therefore, the possibility of optimizing this process is proved. A block diagram, mathematical model and algorithm for calculating energy-saving fuzzy control of the combustion process in the working space of a thermal installation are developed. Combustion Membership functions of fuzzy sets for input linguistic variables are compiled. The rule bases are formulated taking into account the static characteristics of the control object. Examples of technological and linguistic justification of fuzzy controller rules are given. The dynamics of changing the controlled parameter is determined by solving two differential equations. The search for levels of "cut-offs" for the prerequisites of each of the rules using the "minimum" operation in accordance with the compiled database of rules is performed. The defuzzification procedure was performed (bringing it to clarity). The advantages of this system over traditional stabilizing control systems under the action of a set of random factors and a significantly nonlinear relationship between input and output values are shown. Optimal values of scaling factors for the developed automatic control system are determined. Let's consider an example of the formation of a control effect when implementing fuzzy energy-saving control of the combustion process in the working space of the boiler unit No. 3 of the GKP-1A UGPU of Gazprom dobycha Urengoy LLC. The calculations of the amount of inleakage of atmospheric air, excess air flow, the sectional area of the pipe supplying air, the total air flow in the working space of the thermal installation, the volume of natural gas participating in the combustion process, heat resulting from the combustion, the amount of air that did not participate in the combustion process, the amount of heat required to increase the temperature of excess air until the average temperature of the flue gas remaining heat of the combustion reaction, changes in the oxygen concentration in the exhaust flue gases depending on the air flow to the burner. The functional dependence of the flue gas temperature on the natural gas consumption is constructed by approximating the initial data of the regime map of the steam boiler. The dynamic properties of an inertia-delayed controlled process are taken into account when using the Euler method. The combustion control mode influence on the specific fuel consumption is estimated. The effects of using a system with fuzzy control in terms of saving natural gas and electricity over the entire range of performance of a thermal installation are estimated.
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