An Observer-Based Fault-Tolerant Controller for Flexible Buildings-Based on Linear Matrix Inequality Approach

Since failures in sensors degrade the performance of active mass damper (AMD) control systems, a dynamic filter design method, a state observer design method and a robust control strategy are developed and presented in this paper to overcome this deficiency. The filter design method is transformed into a H₂/H∞ control problem that is solved by linear matrix inequality approach. Thus, it is used to perform fault detection and isolation (FDI) for the control systems. The state observer design method uses the acceleration responses as the feedback signal. The detected and isolated fault signals in accelerometers are used to estimate the whole states, that are used to calculate the control force though a robust control strategy based on regional pole-assignment algorithm. Then, the active fault-tolerant control (FTC) is accomplished. To verify its effectiveness, the proposed methodology is applied to a numerical example of a tenstorey frame and an experiment of a single span fourstorey steel frame. Both numerical and experimental results demonstrate that the performances of FTC controller and the control system are improved by the designed dynamic FDI filter to effectively detect and isolate fault signal.