热声发电系统最大声电效率阻抗匹配分析

摘要

为提高热声发电系统的声电转换效率,根据相似理论,结合声学阻抗流源机理进行分析,提出一种永磁直线发电机弹簧机械阻抗和负载电阻抗的声学阻抗匹配设计方法.该方法以提高捕获声功为约束条件,实现声电转换效率最大.进一步地,在弹簧机械阻抗和负载容抗声学阻抗匹配时,给出发电机成为热声发动机声学阻性负载、声学感性负载和声学容性负载的阈值规律.最后搭建实验平台,通过建模、求解及分析设计,验证了发电机声学阻抗匹配方法的有效性,为热声发电系统(TAEGS)的设计提供理论依据.%In order to improve the acoustic-to-electric efficiency for thermoacoustic electric generation system (TAEGS),an acoustic impedance matching design on permanent magnet linear generator (PMLG) is proposed.Based on the similarity theory,analysis and calculations are carried out to study the spring mechanical and load impedance,combining with acoustic impedance current source mechanism.The method obtains the maximum acoustic-to-electric efficiency with the constraints to improve capturing acoustic power for PMLG.Furthermore,the threshold law of external capacitance is achieved for PMLG acting as acoustic impedance,acoustic capacitive and acoustic inductive load on thermoacoustic engine,under the acoustic impedance matching of the spring mechanical impedance and capacitance reactance.Finally,the experimental platform is built.The results show that the effectiveness of the proposed acoustic impedance matching design,providing the theoretical and technical basis for TAEGS design.