Takayoshi Yasuda

A New Adaptive Algorithm for Periodic Noise Control and its Stability Analysis

Abstract The paper considers an active noise feedforward control where a noise consists of a sinusoidal signal and its harmonic components. To overcome drawbacks of ltered-x least mean square algorithm and delayed-x harmonics synthesiser algorithm, a new adaptive algorithm is proposed. Then stability property of the new algorithm is clari ed by using averaging technique and it is shown that there always exists a stable equilibrium point. It is also remarkable that the new algorithm does not require any information on the second path dynamics, i.e., the intervening transfer function. Therefore, the new method could guarantee robust stability without on-line second path modelling. Finally, numerical simulation results show the e ectiveness of the new algorithm.

New DXHS algorithm for periodic vibration control — Numerical simulation and experimental result

The new type of active noise feedforward control (new DXHS algorithm) was proposed and its local stability was analysed to show that the new algorithm can overcome drawbacks of filtered-x least mean square (FxLMS) algorithm as well as delayed-x harmonics synthesiser (DXHS) algorithm. This paper verifies with simulations and experiments how well the new DXHS algorithm works. For the simulations and the experiments, the new DXHS algorithm is transfered from the continuous-time version to the discrete-time version. By observing global behaviors, it is made clear some issues on transient responses until the adjustable parameters converge to the stable equilibrium points.