比例積分微分控制器在管道聲場之主動控制研究

Abstract

本文為一針對一維管道聲場主動噪音控制的實用探討，實驗分成兩個步驟。首先，利用系統識別找出聲學路徑與控制系統路徑的數學模型，其次再依系統模型設計補償器。 第一種直接以訊號產生器之內建訊號做為控制器參考輸入，以主極點配置的方法，針對期望響應來規劃控制系統的輸出，設計一個前饋補償器。實驗結果對於單頻音，管道下游聲音壓力位準及聲音強度位準有20到25dB以及20dB左右的衰減。 第二種針對主動噪音控制系統的控制路徑（第二路徑），補償一個控制器使閉迴路系統提高增益邊界與相位邊界，進而提高閉迴路系統的強健性。實驗結果對於單頻音，管道下游聲音壓力位準及聲音強度位準有10到15dB以及10dB左右的衰減。

This thesis is to study the active control of acoustic fields in duct. There are two parts for the experiment. Firstly, we find the mathematical models of the acoustic path and the control system path by using the modeling method. Secondly, we design controllers by system models. There are two frameworks for the controllers. The first one uses the signals received directly from the function generator as the reference input. A feedforward control by Dominant Pole Assignment algorithm is used to produce the optimum interferential output. The result reveals the attenuation of the acoustic pressure and associated power just downstream the controllable source for pure-tone by 20 to 25 dB and 20 dB can be achieved. In the second one, we study ANC based on a robustly feedback-controlled secondary path.. A robust feedback controller for the secondary path is obtained by increasing Gain and Phase Margin. The result reveals the attenuation of the acoustic pressure and associated power just downstream the controllable source for pure-tone by 10 to 15 dB and 10 dB can be achieved.