一种改进的扬声器Volterra模型研究

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振动与冲击 ›› 2012, Vol. 31 ›› Issue (11) : 158-163.

论文

一种改进的扬声器Volterra模型研究

韦峻峰 1,2 冯海泓 1,2

作者信息 +

An Improved Loudspeaker Volterra Model

Wei Jun-feng1，2 Feng Hai-hong1，2

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文章历史 +

摘要

在研究扬声器振膜的非线性振动时，通常使用Volterra模型进行建模分析。然而受到误差的影响，该模型仅适用于微弱的非线性现象。增大激励电压，频响预测结果的误差逐渐增大。针对这一问题，一种改进的扬声器Volterra模型被提出。该模型引入了振膜平衡位置偏移量对非线性参数的影响，并且在计算位移响应时引入高阶核函数的互调项，使位移响应预测结果更为精确。为了验证模型，搭建了一套可以测量振膜瞬时位移的激光测量系统。实验中测量并计算了振膜平衡位置偏移量和位移的基频响应。结果表明，改进的扬声器Volterra模型与实验结果的一致性较传统模型更好。

Abstract

Volterra model is often applied in analyzing nonlinear vibration of loudspeaker diaphragm. However, with higher input voltage, the error of frequency response has the trend of becoming larger. Therefore, the model is limited to the analysis of systems with weak nonlinearity. Due to the problem, an improved model is proposed. In order to provide a more accurate result, the displacement of rest position of diaphragm was adopted to modify the nonlinear parameters, and the high-order intermodulation terms were evolved in calculating displacement response. A laser measurement system which can be used for measuring instant displacement of diaphragm was built. In the experiment, the displacement of rest position and linear response of displacement were recorded and calculated. The result of improved Volterra model showed a better agreement comparing with the conventional model.