Extended LQG Methodology for Active Structural Controller Design

• Main Authors: Lu Li-teh, 陸立德
• Other Authors: Wei-Ling Chiang
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/04865590961324191517

博士 === 國立中央大學 === 土木工程研究所 === 90 === The LQG optimal control theory used extensively in the literatures for active structural control is extended in this dissertation. Since the LQG controller provides no guarantee for robust stability, we extend the LQG controller to the LQG/LTR controller. Simulations show that LQG/LTR controllers provide better stability margin than those presented in the published literatures. Recently, H2 and H¥ optimal control techniques were introduced for active structural control problem, which results in effectual approaches in the design of controllers for seismic and wind excited buildings. Since LQG optimal control criteria defined in time domain can be numerically equivalent to the H2 optimal control criteria defined in frequency domain with appropriate selection of design weightings. In this dissertation, we present a control strategy that is the simultaneous treatment of both H2 and H¥ criteria and this control strategy quantitatively demonstrates design tradeoffs. Thus, we extend the popular LQG controller to the mixed LQG/H¥ or H2/H¥ controller. This mixed control problem can be formulated by linear matrix inequalities in terms of a common Lyapunov function. Solving linear matrix inequalities is a convex optimization problem. Simulation and design results demonstrates that decreasing H¥ attenuation constraint can be used to reduce the structural response under wind excitations at the expense of increasing H2 performance index and control efforts of the actuator.