Abstract
The article discusses a three-circuit cascade system for automatic control of the water level in a steam boiler using adaptive adjustment of the coefficients of the PID controller. A feature of the proposed system is the use of fuzzy logic for adaptive correction of regulator parameters, which ensures stable and reliable operation of thermal power equipment under various external and internal disturbances. The developed control structure includes three interconnected circuits: water level control through feed water flow, steam flow control, and steam flow control through fuel supply. The use of second-order models, taking into account thermophysical characteristics, makes it possible to increase control accuracy and reduce energy losses. The adaptive adjustment system provides automatic adjustment of the coefficients of the PID controller depending on the current state of the control object. It is shown that the adaptive system effectively compensates for unsteady fluctuations in the water level caused by the characteristics of a two-phase medium and transient conditions, increasing the reliability and stability of the thermal engineering process. The results of numerical modeling and analysis confirm the effectiveness of the proposed approach in conditions of changing object characteristics, noise, delays, and limited information about environmental parameters, which is especially important for complex multiconnected systems.