Robust optimal controller design for a non-minimum phase boiler system with a saturable actuator

Abstract

Dealing with a multivariable non-minimum phase model of a boiler system, a LQG/LTR controller is designed which is well-known for its optimality and robustness. Firstly, the loop transfer function is shaped using LQG method; then, an observer is proposed with the aim of loop transfer recovery. Consequently, the designed controller is reduced to the lowest possible order for the sake of implementation easiness. Moreover, LQG design features are used to analyze stability margins when the system has a saturable actuator. Finally, numerical results demonstrate robustness of the system against the output disturbance, sensor response delay, and actuator saturability.978-1-4244-4602-5/09/$25.00 ©2009 IEEE

Transient analysis of systems exhibiting inverse response and their control with CSTR as a case study

“…An interesting phenomenon which is found in [2] is that right hand sides zeros are not necessary for system to show inverse response. Adaptive control of aircraft with nonminimum phase zeros was performed in [3], robust control for non-minimum phase boiler [4] with LQG control, design of controller for XY non-minimum phase table was performed [5], U-model design for boieng 747 altitude control [6]. As it can be seen in literature previous works are done on specific non-minimum phase plants, inverse systems are only associated with non-minimum systems which is not true as shown in [2].…”