摘要
空耦超声波检测是锂电池无损检测的一种新型方法,在空耦超声波检测锂电池时,由于较低的声波透射率、硬件系统的噪声以及声波在电池中的散射噪声导致采集的超声波信号含有大量噪声,将有效信息淹没,信噪比较低.本文用400 k聚焦探头采集锂电池空耦透射信号,利用小波阈值去噪技术,通过对比信号的信噪比得出选择sym11,db10,coif5小波基,在分解层数为7~10层时,能将有效透射信号与缺陷分离.其中sym11小波基在分解层数为9层时处理的信号达到了最高的信噪比.
The air-coupled ultrasonic detection is a new method for non-destructive testing of lithium batteries.When the ultrasonic coupling was used to detect lithium batteries,the ultrasonic signals collected due to the lower acoustic transmittance,the noise of the hardware system and the scattering noise of the acoustic waves in the battery contain a lot of noise,drowning effective information,and getting signal-to-noise ratio.In this paper,the 400 k focus probe was used to collect the air-coupled transmission signal of lithium battery.The wavelet threshold denoising technique was used to compare the signal-to-noise ratio of the signal to obtain the sym11,db10,and coif5 wavelet bases.When the number of decomposition layers was 7~10,the effective transmission signal can be separated from the defects.The sym11 wavelet base achieved the highest signal-to-noise ratio in the signal with 9 decomposition layers.
作者
张曼
王明泉
杨顺民
郭瑞琦
ZHANG Man;WANG Mingquan;YANG Shunmin;GUO Ruiqi(School of Information and Communication Engineering, North University of China, Taiyuan 030051, China)
出处
《测试技术学报》
2020年第4期304-310,共7页
Journal of Test and Measurement Technology
基金
山西省国际科技合作资助项目(201803D421032)。
关键词
锂电池
空耦超声波
小波降噪
信噪比
lithium battery
air-coupled ultrasonic
wavelet noise reduction
signal-to-noise ratio
