Adaptive phase compensator for vibration suppression of structures with parameter perturbation

The constant all-pass filter has been widely used for phase compensation of control systems. However, it is not applicable to compensating phase deviation caused by additional filters to enhance the signal quality in vibration control systems with parameter perturbation. To overcome this challenge, an adaptive phase compensator (APC) is developed by transforming the constant parameters of an all-pass filter into frequency-dependent parameters. In addition, the sources of phase deviations in the control system are analyzed to design the APC, including the additional filters, non-collocated actuator/sensor configuration, and hardware hysteresis. The phase deviations are determined through simulation and experiment. Polynomial fitting is implemented to obtain the APC parameters. To verify the feasibility of the proposed APC, numerical and experimental efforts are undertaken for buffeting suppression of the vertical tail, which is a typical structure with parameter perturbation. Both results demonstrate that the stability and robustness of control system adopting APC are strengthened compared to that of the control system using a constant phase compensator. Moreover, a control system that adopts APC can also effectively reduce the vibration response for structures with parameter perturbation under harmonic and random excitations. This performance improvement indicates that the proposed APC provides more effective compensation performance for the phase deviation of control systems with time-varying perturbations.