Abstract:

For the feedback active control of noise and vibrations, there are still a few situations where today's adaptive control algorithms do not perform well (slow convergence and/or bad transient response). In this paper, a feedback structure suited for the control of time-varying periodic or time-varying narrow-band disturbances is inspired from a technique used in today's low bit-rate speech coders. The main concept is to separate the information and the processing pertaining to the plant from the information and the processing pertaining to the excitation signal (disturbance). Since the time constants of the variations of the plant are usually much longer than the time constants of the disturbance fluctuations, the adaptation effort can then be put on the prediction of the disturbance. Simulations will be presented, showing that either for low damping systems or multiharmonic disturbance signals, the algorithm presented in this paper can be compared favorably to a popular internal model control (IMC) structure that uses a stochastic gradient algorithm. [Work supported by I.R.S.S.T.]