Application of boiler superheated steam pressure control which based on IMC-PID

The industrial boiler has the characteristics of nonlinear, inertia and lagging. In order to overcome the defects of traditional PID methods and improve the dynamic response and robustness of the system, we design a PID controller which based on internal model control through the adjustment of a single parameter and apply it to the first order plus time-delay (FOPTD) process. Using the first order Pade approximation to approximate the time delay link, the expressions of IMC-PID controller parameters are derived, and they just have only one adjustable parameter λ which is directly related to the dynamic response and robustness of the system. Semi physical simulation equipment SMPT-1000 is used to simulate the industrial boiler combustion control. Its goal is to control the overheated steam pressure. The simulation results show that IMC-PID controller has better dynamic performance on the set-point tracking, disturbance rejection and robustness against parameters change of the system and the outlet pressure can be well controlled.