超薄型壓電式平面喇叭最佳化設計與實現

Abstract

在本文當中，一超薄型壓電式平面喇叭已經發展出來應用在手機上了。此一系統是基於能量法與有限元素法所推導出來，在此模擬的系統當中包含了：電效應系統、機械效應系統、聲場反作用力效應系統、與阻尼效應系統。利用基因演算法與田口實驗計畫法作為基礎理論，其最佳化設計的目標為求得較低之第一共振頻率點與較高之聲壓值，並且利用模擬與實驗來做最佳化之設計，最後利用其結果來做實現與實驗調查。在實驗的結果當中，我們可以發現其壓電式平面喇叭效應可代替動圈式喇叭，並且較為省電。

A miniature piezoelectric panel speaker has been developed for mobile communication in this paper. The system is modeled using the energy method in conjunction with the finite element method. The electrical system, the mechanical system, acoustic loading and the proportional damping are considered in combined fashion. The genetic algorithm (GA) and the Taguchi method are used to optimize this device in order to achieve a low fundamental frequency and a high sound pressure level through numerical simulations and experiments. Designs resulting from the optimization are then implementation and evaluated experimentally. It is found in the experimental results that the piezoelectric panel speakers are able to produce comparable acoustical output with significantly less electrical input than the voice-coil panel speakers.