A Novel Topology for a High-Frequency Pulsed Arc-Welding Power Supply

Pulsed current can constrict the welding arc and enhance arc force, thereby promoting improved stirring within the molten pool. This effect has been widely studied and applied in the welding of metallic materials. In this paper, a high-frequency pulsed DC power supply is proposed for pulsed arc welding applications. The system comprises a constant-current source, a high-frequency pulse modulation circuit, and an energy recovery circuit. The output current amplitude (0 ~ 140 A) is regulated by the constant-current source, while the pulse frequency (20 ~ 40 kHz) and duty cycle (0 ~ 100%) are independently controlled via the pulse switching circuit. To suppress voltage spikes and recover energy from the output cable, an active clamping technique is applied to the switching devices in the modulation stage. This configuration enables rapid rise and fall times of the pulsed current, with controllable current slew rates. Furthermore, by optimizing the pulse control strategy, zero-voltage switching (ZVS) is achieved for the main switches, improving overall efficiency and reducing switching losses. The operating principles of the proposed topology are analyzed in detail, and key design parameters are calculated and presented. To verify the proposed topology, a laboratory prototype was built and tested, featuring a peak pulse current of 140 A and a maximum pulse repetition frequency of 40 kHz.