Active Structural Control of BaseIsolated Building Using EquivalentInputDisturbance Approach With ReducedOrder State Observer

Abstract

Active base isolation has been studied in the last few decades to improve the control performance of base isolation. As a twodegreeoffreedom active disturbancerejection method, the equivalentinputdisturbance (EID) approach shows its validity for structural control. It uses a state observer to estimate the effect of disturbances on a control input channel. However, since the model of a baseisolated building has high degreesoffreedom, the resulting control system has a high order. Thus, the use of a fullorder state observer results in the complexity of a controlsystem implementation. To solve this problem, this paper presents an EID control system that uses a reducedorder state observer (ROSO) to reduce the expense of controlsystem implementation and ensure system reliability. First, the condition of using an ROSO in an EID control system is derived, and the configuration of an ROSObased EID control system is presented. Next, the concept of perfect regulation is used to design the gain of the state observer. A stability condition of the system with prescribed control performance is derived in the form of a linear matrix inequality (LMI) that is used to design the gain of the state feedback. Finally, the seismic control of a baseisolated building demonstrates the validity of the method.