Control And Optimization Of Mian Steam Pressure-Coal Feeding In Boiler Combustion System

Boiler combustion system plays an important role in thermal power plants.The main steam pressure-coal feeding system is the bridge between the boiler and the steam turbine,which affects the combustion efficiency of the boiler.The main steam pressure-coal feeding system is a nonlinear system with large inertia,large hysteresis.In production,the cascade PID control is the most common method for control,but the parameters tuning requires a lot of trial and error,and its robustness is not strong.Aiming at overcoming these disadvantages of cascade PID control,the control method for the main steam pressure-coal feeding system is optimized in this paper.The optimization involves the intelligent controller which is the combination of the PID control and intelligent algorithm.The effect of intelligent controller is verified by simulation in the MATLAB and the experimental verification is earried out with PLC.The main research contents of this paper are as follows:(1)The main steam pressure-coal feeding system of boiler combustion system is controlled and optimized by using intelligent controller after analyzing the current optimization strategy.The control structure of the main steam pressurc-coal feeding system is designed with the coal feeding as the main influencing factor.(2)The main steam pressure-coal feeding optimization system based on fuzzy adaptive PID control is designed.After studying the structure of the fuzzy control system,the fuzzy adaptive PID controller in the main steam pressure-coal feeding control system is designed,which can modify the parameters of the PID controller online by using the output of the two-dimensional fuzzy controller.The fuzzy inference system and the main steam pressure-coal feeding optimization system simulation model are established in the MA-TLAB.The influence of the fuzzy adaptive PID controller with different position and number is discussed and the simulation validation is carried out.(3)The main steam pressure-coal feeding optimization system based on ANFIS-PID control is designed.In order to overcome the shortcoming of the fuzzy adaptive PID control that the fuzzy control rules are too dependent on expert experience,the ANFIS-PID controller is designed after studying the structure and principle of ANFIS.The ANFIS-PID)controller can adjust the parameters of the PID controller online by juxtaposing the three AIFIS with two inputs and single output.The ANFIS inference system and the main steam pressure-coal feeding optimization system simulation model based on ANFIS-PID are established in MATLAB and the simulation validation is carried out.The effect of cascade PID,fuzzy adaptive PID and ANFIS-PID are compared and analyzed.(4)The fuzzy adaptive PID control,ANFIS-PID control and the undisturbed manual/automatic switch control are achieved based on RSLogix 5000 on experimental simulation test platform.The verification takes AB s Compact Logix PLC as the controller,three-layer field bus as the network architecture,and three-tank liquid-flow system as the control object,then the result shows that the designed intelligent controller is better than PID controller.