Fractional Order Filter Enhanced LQR for Seismic Protection of Civil Structures

This study presents fractional order filters to enhance the performance of the conventional linear quadratic regulator (LQR) method,for optimal robust control of a simple civil structure. The introduced filters modify the state variables fed back to the constant gain controller. Four combinations of fractional order filter and LQR are considered and optimized based on a new performance criterion defined in the paper. Introducing fractional order filters is shown to considerably improve the results, for both the artificially generated ground motions and previously recorded earthquake data.