Research And Simulation Of Boiler Superheated Steam Temperature Control

Industrial boilers use superheated steam more frequently as a heat source for energy conversion.To ensure a good control of the superheated steam temperature is an important prerequisite for the proper operation of the boiler.Considering the importance of boiler superheated steam temperature,it is necessary to design a boiler control system,which not only ensures stable and efficient operation of the boiler,but also saves energy and reduces waste,that is also the most important work of the boiler.At present,the industrial site using PID or manual control,but taking its time-varying,large lag and other characteristics into account.In this thesis,the generalized predictive controller and linear active disturbance rejection controller are designed respectively,and the active disturbance rejection control is applied to the hardware-in-the-loop simulation platform to verify its practicality.The main contents of this article are summarized below:First of all,the background and significance of boiler superheated steam temperature control are explained.The current research situation and main problems of the superheated steam temperature control are introduced,and the main methods of superheated steam temperature control are analyzed.Secondly,the superheater is summarized,then the system model is analyzed and processed.The superheated steam temperature of the superheater is analyzed,and the overall scheme is described.The cascade control is adopted,the inner loop adopts PID control,and the outer loop is controlled by the advanced control algorithm.After the inner loop is set,the inertia region of the inner loop and the main steam temperature is regarded as the generalized controlled object,and the transfer function expression is established for the system model.Thirdly,a predictive controller is designed for the superheater system.The generalized predictive control algorithm is used to establish the prediction model corresponding to the system.And then select the performance indicators,online rolling optimization,online identification and feedback correction,the next moment value of the control added to the control valve.The simulation results show that the predictive controller can track the predictive input,but there are some delay limitations,and consider using the active disturbance rejection control algorithm to compensate for the shortcomings of the algorithm.Fourthly,the active disturbance rejection controller is designed for the superheater system.The system model is transformed into a state space expression.Based on this expression,the transition process is designed,the extended state observer is designed,the feedback control law is set up for the error system,and the control law is added to the control valve to realize the control of the superheater.The stability of the superheated steam temperature is analyzed and compared with the predictive control simulation.The results show that the active disturbance rejection control tracking is effective,and the stable control of the superheated steam temperature is achieved.Finally,the ADRC is applied to the SMPT1000 platform,an advanced multifunctional process training system.The experimental platform device and platform software are briefly described.The active disturbance rejection controller is added to the PCS7's SCL source to generate the CFC module,and the platform is built and realized.And then build the configuration interface according to the operation steps of the platform,and put in and run.The results show that the tuning effect is good,temperature output is stable,and the error is small.