应用联合时频分析研究CO_2焊接过程中的电信号

Application of joint time-frequency analysis to electrical signals of CO_2 arc welding

CO2焊接过程的电弧电压、焊接电流信号蕴含了丰富的焊接信息。利用联合时频分析对CO2焊接过程电信号进行研究,分析了短时傅里叶变换窗函数的选择对谱图的时频集聚性的影响,并选择汉宁窗获得了较好的时频集聚性。为了获得CO2焊接电信号中短路过渡的信息,尝试利用时频分析谱图对焊接试验中采集到的几组焊接电流信号进行分析,研究了其能量分布及熔滴过渡的特征,并利用联合时频分析三维谱图,对采用不同焊接参数获得的电弧电压信号进行对比。结果表明,利用联合时频分析对CO2焊接过程电信号进行分析,能够获得更多的有价值信息,该方法具有较好的研究应用前景。

The electrical signals of CO2 arc welding contain plenty of welding information.The joint time-frequency analysis was used to study the electrical signals of CO2 arc welding.The effect of analysis window selecting of short-time Fourier transform to the result of time-frequency analysis spectrum was discussed,and the conclusion that Hanning window has better time-frequency centralizing in analysis was gotten.Based on several welding currents and arc voltages in experiment,the characteristic of energy distribution and metal transfer was investigated by time-frequency analysis to get the information of short-circuiting transfer in electrical signals of CO2 arc welding.The result of analysis in experiment shows that more information in electrical signals can be gotten by time-frequency analysis in CO2 arc welding.This way has a good foreground in research and application.