Abstract: Based on theoretical analysis of welding transformer, a general model of arc welding transformer is established. This model includes all characters such as magnetic nonelinear, hysteresis and eddy losses, leakage flux in ductance. Steady state harmonic current is calculated based on the magnetic characteristic curve of welding trans former. The results show that 3rd harmonic component is the main composition. A measure to eliminate harmonic current is also presented.

Key words: Arc welding transformer, Harmonic analysis, Scratch, Stress field, Temperature field, Brake disc in the alpine environment