Optimizing drum-boiler water level control performance: A practical approach

This paper presents the development of a LQR to optimize pressure and water level control performance of a drum-boiler unit that belongs to a 450MW CCHP plant in Germany. A nonlinear model is initially built within MATLAB/Simulink environment, later enlarged to include the process PID-controllers and control valves regulating mass flow rates. The complete model is validated against data measurements from the plant with very rich excitation. The concluded simulation results adopting the newly proposed control strategy show, that the suggested multivariable control technique outperforms the existing PID-controller in many aspects improving the control performance significantly and yielding much tighter reference value tracking during load changes.