Rejection of unknown periodic disturbances for continuous‐time MIMO systems with dynamic uncertainties

Abstract

Rejection of unknown periodic disturbances in multi-channel systems has several industrial applications that include aerospace, consumer electronics, and many other industries. This paper presents a design and analysis of an output-feedback robust adaptive controller for multi-input multi-output continuous-time systems in the presence of modeling errors and broadband output noise. The trade-off between robust stability and performance improvement as well as practical design considerations for performance improvements are presented. It is demonstrated that proper shaping of the open-loop plant singular values as well as over-parameterizing the controller parametric model can significantly improve performance. Numerical simulations are performed to demonstrate the effectiveness of the proposed scheme.

Reference tracking control and attenuation of unknown periodic disturbances in the presence of noise for unknown minimum‐phase LTI plants

“…[1][2][3][4][5][6] Most of the successful efforts proposed up to now assume that the modeled part of the plant is stable and perfectly known; however, for plants with large parametric uncertainties, online identification of the plant parameters is necessary to achieve the control objective. [1][2][3][4][5][6] Most of the successful efforts proposed up to now assume that the modeled part of the plant is stable and perfectly known; however, for plants with large parametric uncertainties, online identification of the plant parameters is necessary to achieve the control objective.…”

“…Due to its broad applications in high-performance systems, suppression of unknown periodic disturbances acting on dynamical systems has been the subject of considerable research over the past years. [1][2][3][4][5][6] Most of the successful efforts proposed up to now assume that the modeled part of the plant is stable and perfectly known; however, for plants with large parametric uncertainties, online identification of the plant parameters is necessary to achieve the control objective. That is, the controller must be able to identify the parameters of both plant model and disturbance model.…”

Adaptive harmonic steady‐state control for rejection of sinusoidal disturbances acting on a completely unknown system

“…[9][10][11][12][13] If, on the other hand, an accurate model of the system is not available, but the open-loop dynamics are asymptotically stable, then adaptive feedforward cancellation can be used to accomplish disturbance rejection. [14][15][16][17][18][19][20] These approaches use a harmonic regressor consisting of sinusoids at the known disturbance frequencies. The control is generated by updating the amplitudes and phases of these sinusoids in a manner that achieves asymptotic disturbance rejection.…”

Editorial for the special issue on recent advances in adaptive methods for frequency estimation with applications

“…Practical applications can be found in many fields such as control engineering, signal processing, biomedical engineering, navigation, instrumentation and measurement, and power engineering, to mention a few. The purpose of this Special Issue is to present new and effective methods for periodic signal parameter estimation ( [1,2]), together with their use in practical applications with an emphasis on active noise and vibration control ( [3,4]). …”

“…In [4], the authors propose to design and analyze an output-feedback robust adaptive controller for suppression of noise-corrupted unknown periodic disturbances for MIMO continuous-time systems and to discuss the trade-off between robust stability and performance improvement in the presence of plant unmodeled dynamics.…”