Improvements to LQGi/LTR Methodology for Plants with Lightly Damped or LowFrequency Poles

摘要

LQG/LTR design has a tendency to invert the plant's dynamics, which isundesirable if there are plant poles near the imaginary axis. In this study, Static Output Feedback (SOF) is applied to reassign plant poles before LQG/LTR is applied. Alternatively, Robust Eigenstructure Assignment (REA) was used to design the target loop transfer function with an ideal eigenstructure to avoid the undesirable cancellations. Both methods were applied to several aircraft design problems. Results showed that the methods can be effectively used so that the LQG/LTR design has improved stability and performance; however, it was found that each method had strengths and weaknesses.... Linear quadratic gaussian/loop transfer recovery, Static output feedback, Robust eigenstructure assignment, Optimal control, Control robustness.