基于磁-热耦合的扬声器温度场仿真研究  

Simulation of loudspeaker temperature field based on magnetic-thermal coupling

作　　者：李天宇 周静雷[1] 李佳斌 Li Tianyu;Zhou Jinglei;Li Jiabin(School of Electronic Information,Xi'an Polytechnic University,Xi'an 710600,China)

机构地区：[1]西安工程大学电子信息学院,陕西西安710600

出　　处：《电子技术应用》2023年第8期103-107,共5页Application of Electronic Technique

摘　　要：动圈扬声器在大信号驱动时因音圈发热严重,会出现音圈断路、短路和脱胶等热损坏问题,进而导致扬声器单元损坏。通过建立一款动圈扬声器单元的三维有限元模型,进行了基于多物理场耦合的大信号驱动下的扬声器单元稳态温度场与应力场仿真,并通过试验对仿真结果进行了验证。结果表明:在恒压功放的作用下,扬声器单元整体温度随音圈电流频率增大出现先增大后减小的现象,扬声器单元的温度在额定阻抗点处达到峰值,等效应力集中在音圈骨架与定心支片、振膜连接处,会因为高温引发热故障;同时分析了音圈出现热损坏时对扬声器单元暂态温度场的影响。该结果可为动圈扬声器的温度监测和失效分析提供参考。Moving coil loudspeaker may experience thermal damage such as open circuit,short circuit,and debonding when driven by large signals due to severe heating of the voice coil,resulting in damage to the speaker unit.By establishing a threedimensional finite element model of a moving coil loudspeaker unit,the steady-state temperature and stress fields of the speaker unit were simulated under large signal driving based on multi physical field coupling,and the simulation results were verified through experiments.The results show that under the action of a constant voltage power amplifier,the overall temperature of the speaker unit first increases and then decreases with the increase of the frequency of the voice coil current.The temperature of the speaker unit reaches its peak at the rated impedance point,and the equivalent stress is concentrated at the connection between the voice coil skeleton,centering support,and diaphragm,which may cause heating faults due to high temperature.At the same time,the impact of thermal damage to the voice coil on the transient temperature field of the speaker unit was analyzed.This result can provide reference for temperature monitoring and failure analysis of moving coil loudspeaker.

关 键 词：磁热耦合 动圈式扬声器 有限元 数值模拟 

分 类 号：TN912[电子电信—通信与信息系统]