Active vibration control for harmonic disturbances with time-varying frequencies through LPV gain scheduling

A design method for a discrete-time H
_∞
-optimal gain-scheduling controller that rejects harmonic disturbances with time-varying, known frequencies is presented. This is motivated by active vibration control and the controller is experimentally validated on an active vibration control test bench. The harmonic disturbances are modeled as outputs of a linear parameter varying system (LPV) where the frequencies are the varying parameters. The design method and the controller synthesis are discussed and experimental results for constant and time-varying frequencies are shown. The design method leads to a controller that stabilizes the closed-loop system even for arbitrarily fast changes in the disturbance frequencies. In the real-time experiment, the controller suppresses a disturbance consisting of six independent harmonics with frequencies that vary over ranges of 20 Hz.