Abstract: Basing on the discussion of the relation between the signal singularity detection and the wavelet transform modulus maxima, the wavelet analyzing method of the detection of the signal partial singularity is studied for the current signal of the dip transfer CO2 welding. The appropriate wavelet function is selected. Using it, the waveform characteristic of the welding current is extracted. Through the testing experiment of the technologic dynamic characteristic of the arc welding power source, the characteristic information is showed, which is interrelated with the technologic dynamic characteristic of arc welding power source, can be found in the probability density distributions of the extracted current waveform characteristic. Therefore, using the wavelet analyzing method to extract the characteristic information of the technologic dynamic characteristic evaluation is proved to be effective.

Key words: Technologic dynamic characteristic, Arc welding power source, Modulus maxima, Singularity detection, Wavelet analysis