电弧故障信号的小波检测与分析

Wavelet detection and analysis for fault signal of welding arc

焊缝质量受多种因素影响,电弧的稳定性就是其中重要的因素之一。当电弧信号发生异常时,电弧能量就会发生变化,这种能量的变化将会给焊缝成形带来影响。为了分析电弧能量变化,采用小波变换技术,这种有别于传统的信号分析方法能够对信号的局部进行放大和缩小,适合于非平稳信号的分析,尤其是对信号故障点的分析,通过调节时间或频率轴的比例,可获得满意的信号分辨率。实验表明,小波分析法不仅能够判断信号质量,也为焊缝故障的诊断提供了一种新的方法。

The welding quality is affected by various factors,the arc signals stability is just one of important factors that any arc changes will bring great influence to the welding quality.The arc energy will change remarkably when welding arc signal is abnormal,and this energy change will bring a great effect on welding beads formation.In order to analyze the arc energy change,this paper adopts the technique of wavelet transform that is different from the traditional signal analysis methods.By using this method,the ratio of amplification for the local characteristics of the arc signal can be adjusted and this method is a very suitable for non-stationary signal analysis,especially for the signal fault analysis,and satisfied signal resolution can be obtained by adjusting the ratio of time or frequency axis.Experimental results show that the wavelet analysis method not only can distinguish the signal quality,but also can provide a new way for the welding beads failure diagnosis.