Study On Control Method For The Top Pressure Of Blast Furnace In An Emergency Process Of TRT System

Top Gas Pressure Recovery Turbine Unit (TRT) is internationally recognized as a valuable energy recovery unit. Although the energy of pressure wasted in the Pressure Reducing Valve Group or Bischoff Precipitator can be recovered by TRT, however, the stability of the top gas pressure of the blast furnace must be ensured. Therefore to operation TRT the stability of the top gas pressure should be ensured, especially when the TRT is in an emergency process.Based on control requirements of the top gas pressure of the TRT, a model construction of top-pressure control system was established through analyzing the configuration of TRT system firstly, and then using classical step response method to identify the system parameter, a practicable system model was deduced at last. Then a feedforeword controller is designed for the TRT emergency process.The principles and characteristics of the nonlinear PID controller are introduced, and also the principles and the characteristics of the Smith Predictor Controller are introduced, that Smith Predictor Controller is sensitive to the object model error. Based on these above, this paper presents a design of Smith Predictor-nonlinear PID controller, in order to improve the control effect, and to enhance the robustness of the control system.The design of Smith Predictor-nonlinear PID controller is simulated with MATLAB simulation tool, to demonstrate its effectiveness and robustness. When the TRT is in an emergency process, a feedforward controller is designed to overcome the interference, this process is also simulated with MATLAB, and the simulation results demonstrate the control effect.Finally, the components of the TRT control system, including logic control systems, feedback control systems and the monitoring system, are introduced. Based on the characteristics of the ABB DCS system, the hardware system, including the configuration of the process control station, the configuration of the Project I/O module and the configuration of hardware parameters, are designed; Also the software system, including monitoring software system, process control software system, are designed.