Direct and indirect adaptive regulation strategies for rejection of time varying narrow band disturbances applied to a benchmark problem

The paper will compare the performances which can be obtained using a direct adaptive regulation scheme based on the Youla-Kučera (YK) parametrization of the controller and using an adaptive finite impulse response (FIR) filter for implementing the internal model of the disturbance with a new indirect adaptive regulation scheme. The main features of this new scheme are: (i) the use of adaptive Band-stop Filters (BSFs) tuned at the frequencies of the disturbance instead of the Internal Model Principle (IMP) and (ii) a procedure for direct identification of frequencies contained in the disturbance. The use of adaptive BSFs allows to introduce the desired attenuation of the disturbance (instead of total rejection) and allows to get a much better shaping of the output sensitivity function (to meet the specification for the tolerated amplification outside the frequencies of the disturbance). The two approaches are comparatively evaluated on the benchmark simulator and on the benchmark active vibration control system.