Abstract: With extensive application of high performance thin sheet alloy and development of arc welding technology based on real-time energy waveform control, higher requirements for dynamic characteristics of arc welding inverter is put forward.Through phase-shifted full-bridge inverter circuit analysis, the main circuit can be equivalent to Buck model.The current transfer function of small signal equivalent circuit model is derived by using circuit theory.The influence factors of dynamic characteristics of arc welding inverter are analyzed by using automatic control theory.The specific design is proposed for the slope compensation based on peak current feedback.It is concluded that dynamic characteristics of arc welding inverter based on peak current feedback do not depend on reactance value of output circuit.The analysis process is confirmed by simulation and experimental results of actual circuit.