压电陶瓷扬声器系统优化与设计研究

发布时间：2018-05-11 01:06

本文选题：压电陶瓷扬声器 + 扬声器系统　；参考：《南京大学》2015年硕士论文

【摘要】：压电陶瓷扬声器的基本工作原理是,通过逆压电效应使压电陶瓷片产生弯曲振动,向外辐射声波,与传统的电动式扬声器有很大区别。压电陶瓷扬声器一般由五层以上的压电层及金属层构成,由于其结构及振动模式的复杂性,使得目前与压电陶瓷扬声器相关的研究极为有限,更没有一个成熟的模型来表征压电陶瓷扬声器单元的振动。事实上,压电陶瓷扬声器的主要问题是低频拓展不够,而使用时一般都包含前腔或后腔,作为一个扬声器系统工作,因此,研究压电陶瓷扬声器系统的中低频特性可以解决很多问题。本文通过激光测试压电陶瓷扬声器的位移曲线来分析其振动模式,发现压电陶瓷扬声器在中低频仍然是以一种整体振动的运动方式为主。以此为基础,讨论了压电陶瓷扬声器应用腔体时的系统优化设计,分析了压电陶瓷扬声器中前腔结构和后腔结构带来的影响。通过实验设计与分析,发现：压电陶瓷扬声器附加前腔时,前腔开孔数量越多,Q值越大,且系统中高频峰的位置越往后移；附加前腔容积越大,中频补偿越靠前,高频下降越快；压电陶瓷扬声器中附加后腔容积越大,则系统共振频率越低。同时,本文还引入了管道倒相式结构,通过理论分析和实验设计证明了管道倒相式结构在压电陶瓷扬声器中同样适用,并在合理的设计后可以有效地提升压电陶瓷扬声器系统的低频声压级,拓宽压电陶瓷扬声器系统的有效频率范围。
[Abstract]:The basic working principle of the piezoelectric ceramic loudspeaker is that the piezoelectric ceramic plate produces bending vibration and radiates acoustic waves through the inverse piezoelectric effect, which is very different from the traditional electric loudspeaker. Piezoelectric ceramic loudspeakers are generally composed of five or more layers of piezoelectric and metal layers. Due to the complexity of its structure and vibration mode, the current research on piezoelectric ceramic loudspeakers is very limited. There is also no mature model to characterize the vibration of piezoelectric speaker units. In fact, the main problem with piezoelectric ceramic loudspeakers is that the low frequency expansion is not enough, and when used, they usually contain front or rear cavities to work as a loudspeaker system, so, Many problems can be solved by studying the middle and low frequency characteristics of piezoelectric ceramic loudspeaker system. In this paper, the displacement curve of piezoelectric ceramic loudspeaker is measured by laser to analyze its vibration mode. It is found that the medium and low frequency of piezoelectric ceramic loudspeaker is still a movement mode of whole vibration. Based on this, the system optimization design of piezoelectric ceramic loudspeaker is discussed, and the influence of front cavity structure and rear cavity structure on piezoelectric ceramic loudspeaker is analyzed. Through experimental design and analysis, it is found that the larger the number of openings in the front cavity and the more the position of the high frequency peak in the system are, the larger the volume of the additional front cavity is, and the more the if compensation is forward, the larger the volume of the additional front cavity is, the greater the Q value of the front cavity is, and the higher the position of the high frequency peak is, The larger the volume of the additional rear cavity in the piezoelectric ceramic loudspeaker, the lower the resonance frequency of the system. At the same time, the inverted phase structure of pipeline is introduced in this paper. The theoretical analysis and experimental design prove that the inverted phase structure of pipeline is also suitable for the piezoelectric ceramic loudspeaker. After reasonable design, the low frequency sound pressure level of piezoelectric ceramic loudspeaker system can be raised effectively, and the effective frequency range of piezoelectric ceramic loudspeaker system can be widened.
【学位授予单位】：南京大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN643

【参考文献】